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Objectives: This study evaluates the prognostic impact of the new grading system for lung adenocarcinoma, stratified by lymphadenectomy extent., Materials and Methods: We analyzed 1258 lung adenocarcinoma patients who underwent curative resections between 2006 and 2017. We analyzed overall survival (OS), cancer-specific survival (CSS), and recurrence-free survival (RFS) across tumor grades and lymphadenectomy extent, categorized as IASLC-R0 (complete resection) or R(un) (uncertain resection)., Results: The median age of cohort was 63 and 41.9 % were male. The majority had undergone lobectomy. The distribution of tumors was 274 grade 1, 558 grade 2, and 426 grade 3 cases. After a median follow-up time of 102 months, the 10-year OS/CSS/RFS rates worsened significantly across grade 1-3: 92.4/99.3/92.3 %, 77.8/87.5/71.7 %, and 63.6/70.2/52.0 %, respectively (p < 0.001). Multivariate Cox regression analysis identified grade 3, R(un) lymphadenectomy, higher Charlson Comorbidity Index, smoking history, thoracotomy, higher pathology stage, and angiolymphatic invasion as independent prognostic factors for lower OS, CSS, and RFS. Furthermore, grade 3 patients benefited significantly from IASLC-R0 lymphadenectomy, showing significantly better OS and RFS than those who underwent R(un) lymphadenectomy (p = 0.007 for OS, p = 0.001 for RFS, post-propensity score matching). Among grade 3 tumors underwent R0 or R(un) resections found the incidence rates of local, distant, and simultaneous local and distant recurrence were 8.5 % vs 13.7 %, 11.0 % vs 12.2 %, and 11.0 % vs 20.6 %, respectively., Conclusion: Surgical outcomes for lung adenocarcinoma have declined across grades 1-3. IASLC-R(un) treatment worsens OS and RFS in grade 3. Intensive monitoring and adjuvant therapy should be considered when patients with grade 3 lung adenocarcinoma undergo R(un) lymphadenectomy., Competing Interests: Declaration of competing interest There is no conflict of interest., (Copyright © 2024 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.)

Background: The standard treatment for pathological N2 (pN2) non-small-cell lung cancer (NSCLC) patients is definitive chemoradiation. Surgery might be beneficial for resectable pN2 disease, so we investigated the recurrence-free interval of upfront surgery for selected patients with resectable pN2 disease., Methods: The clinicopathologic characteristics of patients with pN2 NSCLC who underwent upfront anatomical resection at Taipei Veterans General Hospital from 2011 January to 2019 December were retrospectively reviewed. A Cox regression model was used to identify prognostic factors of recurrence-free survival (RFS)., Results: In total, 84 patients after curative lung anatomic resection were analyzed, with a 44-month median survival. The 1-, 3-, and 5-year RFS rates were 63.1%, 31.3%, and 19.9%, respectively, with a median RFS of 18.9 months. Multivariable cox regression analysis identified that the significant predictor for RFS was a tumor size of more than 3 cm (hazard ratio [HR] = 1.74, 95% CI, 1.07-2.83, p = 0.027). Visceral pleural invasion, LN harvest number, tumor stage, and N2 status including single zone (N2a) or multiple zones (N2b) were not prognostic factors in this study., Conclusion: Upfront surgery for resectable N2 disease achieved favorable outcomes in selected patients, especially better recurrence control with limited tumor size. Therapeutic advances might encourage surgeons to aggressive intervention., Competing Interests: Conflicts of interest: Dr. Han-Shui Hsu, an editorial board member at Journal of the Chinese Medical Association , had no role in the peer review process of or decision to publish this article. The other authors declare that they have no conflicts of interest related to the subject matter or materials discussed in this article., (Copyright © 2023, the Chinese Medical Association.)

Background: Lung adenocarcinoma-an aggressive and life-threatening malignancy-is a type of non-small-cell lung cancer. Despite medical advancements, the prognosis of lung adenocarcinoma remains unfavorable, likely because of its heterogeneous nature. Furthermore, few subtype-specific treatments are available for lung adenocarcinoma. This study was conducted to explore the molecular subtypes of lung adenocarcinoma., Methods: We performed a joint analysis of transcriptome and proteome data from East Asian patients with lung adenocarcinoma (nonsmokers, 86.5%)., Results: Four novel subtypes were identified based on distinct molecular characteristics: subtypes I, II, III, and IV. In patients with subtype I lung adenocarcinoma, eukaryotic translation initiation factor 4 gamma 1 activates cell proliferation; inhibiting this factor suppresses tumor growth, and reducing its level induces autophagy. Subtype II is characterized by Kristen rat sarcoma viral oncogene homolog-activating oncogenesis; the onset age of this subtype is the lowest among all subtypes. Subtype III manifests as an advanced disease at diagnosis; it is characterized by a core serum response-related oncogenic signature, which indicates poor overall survival in Western patients with lung cancer. Subtype IV is more common in men than in women; it has astroglial characteristics. A Connectivity Map analysis revealed that the oncogenic expression patterns corresponding to subtypes I, II, III, and IV can be reversed by the inhibitors of Inhibitor of κB (IκB) kinase (eg, withaferin A), mammalian target of rapamycin (eg, everolimus), Src proto-oncogene (Src) (eg, saracatinib), and Transforming Growth Factor (TGF)-β/Smad (eg, LY-364947), respectively., Conclusion: This study introduced an innovative multiomics data analysis pipeline. Using this approach, we successfully identified four molecular subtypes of lung adenocarcinoma and their candidate therapeutic agents. The newly identified subtypes can be combined with the current biomarkers to generate a comprehensive roadmap for treatment decision-making., Competing Interests: Conflicts of interest: Dr. Shih-Hwa Chiou and Dr. Han-Shui Hsu, editorial board members at the Journal of the Chinese Medical Association , have no roles in the peer review process or decision to publish this article. The other authors declare that they have no conflicts of interest related to the subject matter or materials discussed in this article., (Copyright © 2023, the Chinese Medical Association.)

Background: Stereotactic ablative radiotherapy (SABR) is now the standard of care for patients with inoperable early-stage lung cancer. Many of these patients are elderly. EGFR (epidermal growth factor receptor) mutation is also common in the Asian population., Methods: To evaluate the effects of old age and EGFR mutation on treatment outcomes and toxicity, we reviewed the medical records of 71 consecutive patients with inoperable early-stage non-small cell lung cancer (NSCLC) who received SABR at Taipei Veterans General Hospital between 2015 and 2021., Results: The study revealed that median age, follow-up, Charlson comorbidity index, and ECOG score were 80 years, 2.48 years, 3, and 1, respectively. Of these patients, 37 (52.1%) were 80 years or older, and 50 (70.4%) and 21 (29.6%) had T1 and T2 diseases, respectively. EGFR mutation status was available for 33 (46.5%) patients, of whom 16 (51.5%) had a mutation. The overall survival rates at 1, 3, and 5 years were 97.2, 74.9, and 58.3%, respectively. The local control rate at 1, 3, and 5 years was 97.1, 92.5, and 92.5%, respectively. Using Cox proportional hazards regression we found that male sex was a risk factor for overall survival (p = 0.036, 95% CI: 1.118-26.188). Two patients had grade 2 pneumonitis, but no other grade 2 or higher toxicity was observed. We did not find any significant differences in treatment outcomes or toxicity between patients aged 80 or older and those with EGFR mutations in this cohort., Conclusion: These findings indicate that age and EGFR mutation status do not significantly affect the effectiveness or toxicity of SABR for patients with inoperable early-stage NSCLC., (© 2023 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.)

Purpose: Develop a method for extracting smoking status and quantitative smoking history from clinician notes to facilitate cohort identification for low-dose computed tomography (LDCT) scanning for early detection of lung cancer., Materials and Methods: A sample of 4,615 adult patients were randomly selected from the Multiparameter Intelligent Monitoring in Critical Care (MIMIC-III) database. The structured data were obtained by queries of the diagnosis tables using the International Classification of Diseases codes in use at that time. Unstructured data were drawn from clinician notes via natural language processing (NLP) using named entity recognition and our clinical data processing and extraction algorithms to identify two main clinical criteria for each smoking patient: (1) pack years smoked and (2) time from quit date (if applicable). A subset of 10% of the patient charts were manually reviewed for accuracy and precision., Results: The structured data revealed 575 (12.5%) ever smokers (current plus past use). None of these patients had quantification of their smoking history, and 4,040 (87.5%) had no smoking information in the diagnosis tables; consequently, a cohort of patients eligible for LDCT could not be determined. Review of the physician notes by NLP disclosed 1,930 (41.8%) ever smokers of whom 537 were active smokers and 1,299 former smokers, and in 94 cases, it could not be determined if they were active or former smokers. A total of 1365 patients (29.6%) had no smoking data recorded. When the smoking and the age criteria for LDCT were applied to this group, 276 were found to be eligible for LDCT using the USPSTF criteria. As determined by clinician review, our F-score for identifying patients eligible for LDCT was 0.88., Conclusion: Unstructured data, obtained by NLP, can accurately identify a precise cohort that meets the USPSTF guidelines for LDCT.

This study aimed to evaluate the protein expression of glutathione peroxidase 4 (GPX4) in resected non-small cell lung cancer (NSCLC). The clinical relevance and prognostic significance of GPX4 expression were analyzed. We reviewed patients with resected NSCLCs at Taipei Veterans General Hospital between September 2002 and January 2018. Available paraffin-embedded specimens were retrieved for immunohistochemistry (IHC) staining to detect GPX4 expression. The cutoff value for defining GPX4 positivity was determined according to the percentage of tumor stained in the microscopic field. The correlation between immune expression, clinicopathologic data, overall survival (OS), and disease-free survival (DFS) were analyzed. A total of 265 NSCLC specimens were retrieved for IHC staining. GPX4 expression positive was in 192 (72.5%) according to a cutoff value of 5%. GPX4 was a significant prognostic factor for OS and DFS on multivariate analysis at both 5% and 25% cutoff values. GPX4 expression was associated with poor OS and DFS, especially in lung adenocarcinoma (p = 0.008, and 0.027, respectively). In conclusions, IHC analysis revealed that GPX4 expression was associated with poor survival outcomes in patients with resected lung adenocarcinoma. Further research is needed to understand the role of GPX4 in tumorigenesis and the underlying mechanism responsible for survival outcomes in patients with resected lung adenocarcinoma., (© 2022. The Author(s).)

Background: To evaluate the long-term outcomes after surgical resection for stage I lung adenocarcinoma based on the percentage of lepidic component (LC) and invasive tumor size (IS)., Methods: The clinicopathological characteristics of 1049 patients with stage I lung adenocarcinoma who underwent surgery between 2006 and 2016 were retrospectively reviewed. Tumors were categorized into groups: A (LC ≥ 50%) and B (LC < 50%). Groups A0 and A1 consisted of minimally invasive adenocarcinomas (MIA) and other lepidic-predominant invasive adenocarcinomas, respectively. Group B was categorized into B1 (IS ≤ 1 cm), B2 (1 < IS≤2 cm), and B3 (2 < IS≤3 cm) by invasive tumor size and divided into subgroups (B1[lep+]/[lep-], B2[lep+]/[lep-], and B3[lep+]/[lep-]) according to the presence[lep+] or absence[lep-] of LCs. Cumulative incidence of recurrence (CIR) and cancer-specific survival (CSS) were examined., Results: LC decreased with increasing IS. Only 24 (8.5%) tumors in group A had an IS >1 cm. 10-year CIR and CSS were 15.2% and 86.0%. LC and IS were found to be independent predictors of CSS. Patients in group A had 1.4% 10-year CIR and 100% 10-year CSS. In group B, a significantly higher CIR and worse CSS were observed as IS increased (p < 0.001), but LC was not a predictor for CSS (p = 0.593). No significant differences in CIR or CSS were found in presence of LC or not when LC < 50% (B1[lep+]/[lep-], B2[lep+]/[lep-], and B3[lep+]/[lep-]: p = 0.36/0.48, p = 0.82/0.94, and p = 0.90/0.37, respectively)., Conclusions: LC≥50% tumors demonstrated excellent prognosis regardless of IS. The outcomes of LC < 50% tumors were well predicted by IS, corresponding to the T-staging system. The predictive value of LC for prognosis became insignificant., (© 2022 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.)

Background: Differing surgical series for the treatment of primary lung tumor with synchronous oligometastatic stage IV non-small cell lung cancer (NSCLC) have been published; however, outcomes remain ambiguous., Methods: Patients with synchronous oligometastatic stage IV NSCLC treated from 2005 to 2017 were enrolled to identify the impact of treatment sequence (primary lung resection vs systemic treatment) on progression-free survival (PFS) and overall survival (OS)., Results: Tumor resection occurred in 51 patients (84% adenocarcinoma, 55% nonsmokers, and 65% driver gene mutation) before or after systemic treatment in 33 (64.7%) and 18 (35.3%) patients, respectively. Patients who received resection first were older (62.1 vs 54 years) and at a less advanced intrathoracic stage (18% vs 44%). No significant differences were noted regarding perioperative complications (30% vs 28%), hospital length of stay (9.0 vs 10.5 days), percentage of disease progression (91% vs 94%), overall death (70% vs 78%), median PFS (14.0 vs 22.8 months), and OS (44.6 vs 53.2 months). Patients with single-organ metastasis had significantly longer PFS and OS than those with oligometastases (17.5 vs 12.8 months, P = .040; and 55.6 vs 39.8 months, P = .035), respectively. Multivariable Cox analysis identified nonsolitary metastasis as the only independent predictor of PFS (hazard ratio, 2.27; 95% confidence interval, 1.07-4.81; P = .033)., Conclusions: Primary lung resection before or after induction systemic therapy may benefit patients with oligometastatic NSCLC. Future randomized clinical trials examining the effect of treatment sequence is recommended., (Copyright © 2022 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

The prognostic role of histological patterns of dominant tumor (DT) and second dominant tumor (sDT) in synchronous multiple adenocarcinoma (SMADC) of lung remains unclear. SMADC patients diagnosed between 2003 and 2015 were retrospectively reviewed. DT and sDT were defined as two maximum diameters of consolidation among multiple tumors. Histological pattern was determined using IASLC/ATS/ERS classification system. DTs were divided into low- (lepidic), intermediate- (acinar, papillary) and high-grade (micropapillary, solid) subtypes, and sDTs into non-invasive predominant (lepidic) and invasive predominant (acinar, papillary, micropapillary, solid) subtypes. During mean 74-month follow-up among 149 nodal-negative patients having SMADC resected, recurrence was noted in 44 (29.5%), with significantly higher percentage in high-grade DT (p < 0.001). Five-year overall (OS) and disease-free (DFS) survivals in low-, intermediate- and high-grade DT were 96.9%, 94.3%, 63.3% (p < 0.001) and 100%, 87.2%, 30.0%, respectively (p < 0.001). Cox-regression multivariate analysis demonstrated high-grade DT as a significant predictor for DFS (Hazard ratio [HR] 5.324; 95% CI 2.570-11.462, p < 0.001) and OS (HR 3.287; 95% CI 1.323-8.168, p = 0.010). Analyzing DT and sDT together, we found no significant differences in DFS, either in intermediate- or high-grade DT plus invasive or non-invasive sDT. DT was histologically an independent risk factor of DFS and OS in completely resected nodal-negative SMADCs.

Objectives: The present study aimed to clarify the association between preoperative biopsy and surgical outcomes in clinical stage I non-small-cell lung cancer (NSCLC) with different proportions of ground-glass opacity (GGO)., Methods: Data on patients who underwent pulmonary resection for NSCLC from 2006 to 2016 were drawn from a prospective registered database and analysed retrospectively. Patient characteristics collected included tumour size, location and staging, surgical approach, consolidation-tumour ratio, histopathology and the presence or absence of preoperative biopsy to identify the independent prognostic factors of disease-free survival (DFS) and cancer-specific survival. A 1:1 propensity score matching was conducted between the preoperative biopsy and reference groups based on their baseline characteristics measured before the decision for preoperative biopsy., Results: A total of 1427 patients were collected to achieve an overall 5-year DFS as 84.5% (median follow-up: 67.3 months), stratified to be 99.5% in the GGO-dominant group (n = 430) and 78.2% in the solid-dominant group (n = 997). Only 2 patients (0.5%) in the GGO-dominant group experienced tumour recurrence. For solid-dominant tumours matched with propensity scores (279 in preoperative biopsy vs 279 in reference group), the independent predictors of DFS included preoperative biopsy, sublobar resection, pathological staging and angiolymphatic invasion. Preoperative biopsy was a predictor of cancer-specific survival in univariable analysis but was not in multivariable analysis. Significant differences were also found between matched groups in those with late-delay surgery, but not in patients receiving preoperative biopsy with early-delay surgery (≤21 days)., Conclusion: Preoperative biopsy may worsen surgical outcomes in patients with clinical stage I, solid-dominant NSCLC., (© The Author(s) 2020. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Background: Preoperative positron emission tomography/computed tomography (PET/CT) is recommended as a guideline for staging of lung cancer. However, for patients with pulmonary ground-glass opacity (GGO) nodules who are supposed to have a relatively low risk of incidence of lymphatic metastasis, it remains uncertain whether PET/CT is more effective than consolidation-to-tumor ratio (CTR) in the prediction of regional lymphatic metastasis., Methods: The data on patients who underwent surgery for lung cancer from 2011 to 2016 were collected retrospectively, which included CTR, results of PET/CT, and pathological characteristics. The patients who had undergone preoperative PET/CT were identified to find the risk factors for lymphatic metastasis. A receiver operating characteristic (ROC) curve and multiple logistic regression was utilized to clarify the predictive value of CTR and main tumor maximal standardized uptake value (SUVmax)., Results: Among 217 patients who had PET/CT before lobectomy, chest computed tomography revealed that 75 patients had CTR greater than 62%. The patients with lymphatic metastasis were shown to have higher CTR and higher main tumor SUVmax. Multiple logistic regression showed that younger age (<60 years), higher main tumor SUVmax on PET/CT, and greater CTR were independent predictive factors for lymphatic metastasis. The area under the ROC curve was comparable, 0.817 for CTR, and 0.816 for main tumor SUVmax., Conclusions: The present study revealed that CTR was not inferior to main tumor SUVmax considering the predictive power for lymphatic metastasis preoperatively in lung cancer patients with a GGO component. PET/CT might not be necessary preoperatively in selected patients., (© 2021 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.)

Introduction: Few studies have investigated the impact of active surveillance on pathological outcome ground-glass nodules (GGNs). We focused on GGNs that needed preoperative localization before resection and compared the pathological results between GGNs that underwent early resection or active surveillance., Methods: We retrospectively reviewed data of resected GGNs between January 2017 and December 2018. GGNs were classified by early resection (Group A) and active surveillance (Group B). Group B was subclassified as no (Group B1) and with (Group B2) growth, and intergroup comparison of pathological results was undertaken., Results: In total, 509 GGNs (124, 275, and 110 in Groups A, B1, and B2, respectively) were included. Malignancy (primary lung cancer) ratios were 68% and 72% in Groups A and B (p = .312) and 65% and 92% in Groups B1 and B2, respectively (p < .001). The ratios of invasive carcinoma were 21.4%, 9.6%, and 35.6% in Groups A, B1, and B2, respectively. Predictors for invasive carcinoma included history of lung cancer, GGN size ≥ 10 mm, solid size ≥ 6 mm, and GGN growth., Conclusions: The pathological findings were similar for GGNs in the early resection and active surveillance groups. However, rates of malignancy and invasive carcinoma increased in the group that manifested growth during active surveillance., (© 2020 Wiley Periodicals LLC.)

Background: The treatment for stage III non-small cell lung cancer (NSCLC) often involves multi-modality treatment. This retrospective study aimed to evaluate whether multidisciplinary team (MDT) discussion results in better patient survival., Materials and Methods: MDT discussion was optional before February 2016 and was actively encouraged by the MDT committee beginning February 2016. We reviewed the medical charts and computer records of patients with stage III NSCLC between January 2013 and December 2018., Results: A total of 515 patients were included. The median survival of all the patients was 33.9 months (M). The median survival of patients who were treated after MDT discussion was 41.2 M and that of patients treated without MDT discussion was 25.7 M (p = 0.018). The median survival of patients treated before February 2016 was 25.7 M and that of patients treated after February 2016 was 33.9 M (p = 0.003). The median survival of patients with stage IIIA tumors and those with stage IIIB tumors was 39.4 M and 25.7 M, respectively (p = 0.141). Multivariate analysis showed that MDT or not (p<0.001), T staging (p = 0.009), performance status (p<0.001), and surgery (p = 0.016) to be significant prognostic factors., Conclusion: The results of the study show that MDT discussion results in survival benefit in patients with stage III NSCLC. The MDT discussion, performance status, and if surgery was performed were independent prognostic factors for patients with stage III NSCLC., Competing Interests: The authors have declared that no competing interests exist.

Lung cancer is the most common cause of cancer death in the world. However, recent studies have found that patients with pulmonary ground-glass opacity (GGO) have a better prognosis. Considering its low invasiveness, sublobar resection may be an appropriate treatment of choice. Low-dose computed tomography (CT) is recommended for the high-risk groups of lung cancer. Patients with nonsolid nodule are suggested to take annual low dose CT following-up. For part-solid or solid nodules, the solid component size less or more than 8 mm is the watershed of surgical treatment. Increasing tumor size is a hint of malignancy. Biopsy can be performed for clinically highly suspected malignant nodules. The endobronchial ultrasound biopsy, CT-guide biopsy, or surgical excision are the mainstream for the diagnosis of lung nodules. But for treatment, the sublobar resection is the mainstream of pulmonary GGO. A precise localization technique makes surgeons get enough resection margin and preserve more pulmonary function of the patients. The different localization technique is suitable for different kind nodular position. For patients with pure pulmonary GGO, annual low dose CT checkup is suitable. If the tumor size or solid part of the tumors increased gradually, adequate sublobar resection after tumor localization technique may provide good prognosis and preserve more pulmonary function of the patients.

Objectives: An optimal method for preoperative localization of small lung nodules is yet to be established, and there are few comparative studies in the literature. In the present study, we aimed to compare electromagnetic navigation-guided and computed tomography (CT)-guided methods of percutaneous transthoracic localization., Methods: The clinical, radiographic, surgical and pathological data of patients who underwent electromagnetic navigation-guided localization (EMNGL) and CT-guided localization (CTGL) before uniportal video-assisted thoracic surgery (VATS) were reviewed. Propensity score matching analysis was performed to compare the localization and surgical results., Results: After matching, 25 EMNGL and 50 CTGL patients were included in the analysis. In the CTGL group, pulmonary haemorrhage and pneumothorax were noted in 56% and 34% of patients, respectively, on postprocedural CT scans. Successful localization was achieved in 96% and 100% of patients in the EMNGL and CTGL groups, respectively (P = 0.333). The median time in the operation room was significantly shorter in the CTGL group {142.5 [interquartile range (IQR) 123.8-175.0] vs 205.0 [IQR 177.5-290.0] min, P < 0.001}. In contrast, EMNGL significantly decreased the total time [205.0 (IQR 177.5-290.0) vs 324.0 (IQR 228.3-374.0) min, P = 0.002]. The median duration of chest drainage was 1 day shorter in the EMNGL group [2.0 (IQR 1.5-2.5) vs 3.0 (IQR 2.0-3.0), P = 0.002]; the surgical complication rates were comparable between the 2 groups., Conclusions: The localization and surgical results were similar between the EMNGL and CTGL groups. EMNGL is comparable to conventional CTGL with respect to preoperative localization of small lung nodules before uniportal VATS., (© The Author(s) 2020. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Background: This study aimed to compare survival between standard lobectomy and surgeons' preference sublobar resection among patients with stage I non-small cell lung cancer (NSCLC)., Methods: Medical records of patients undergoing pulmonary resection between 2006 and 2016 were reviewed retrospectively. Differences in disease-free survival (DFS) and DFS-associated factors between patients receiving lobectomy and surgeons' preference sublobar resection were analyzed after 1-1 propensity score-matching (n = 119 per group)., Results: In total, 1064 pathological stage I NSCLC patients were identified, including 816 (76.7%) who underwent lobectomy, 111 (10.4%) who underwent sublobar resection as a compromised procedure (medically unfit), and 137 (12.9%) who underwent surgeons' preference sublobar resection. Rates of five-year DFS for patients undergoing lobectomy, medically unfit, and surgeons' preference sublobar resection were 88.7%, 71.0%, and 93.4%, respectively (P < 0.001). Multivariable Cox regression analysis demonstrated that radiological solid-appearance (adjusted hazard [aHR] = 2.908, P = 0.003), PL2 invasion (aHR = 1.970, P = 0.024), and angiolymphatic invasion (aHR = 2.202, P = 0.005) were significantly associated with lower DFS after adjusting for surgeons' preference sublobar resection (aH = 1.031, P = 0.939). Subgroup analysis of all 403 solid-dominant patients demonstrated equivalent five-year DFS between surgeons' preference sublobar resection and lobectomy (87.7% and 84.1%, respectively, P = 0.721). Propensity-matched analysis showed no differences in five-year DFS in stage I NSCLC patients undergoing lobectomy or surgeons' preference sublobar resection (90.5% vs. 93.4% P = 0.510), and DFS for surgeons' preference sublobar resection remained an insignificant factor (aHR = 0.894, P = 0.834)., Conclusions: Carefully selected patients who have undergone surgeons' preference sublobar resection have comparable outcomes to those receiving lobectomy for stage I NSCLC <3 cm., Key Points: Significant findings of the study Intended sublobar resection has a good outcome. What this study adds Sublobar resection is applicable for stage I NSCLC <3 cm., (© 2020 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.)

Background: Recent advancements in cancer biology field suggest that glucose metabolism is a potential target for cancer treatment. However, little if anything is known about the metabolic profile of cancer stem cells (CSCs) and the related underlying mechanisms., Methods: The metabolic phenotype in lung CSC was first investigated. The role of collagen XVII, a putative stem cell or CSC candidate marker, in regulating metabolic reprogramming in lung CSC was subsequently studied. Through screening the genes involved in glycolysis, we identified the downstream targets of collagen XVII that were involved in metabolic reprogramming of lung CSCs. Collagen XVII and its downstream targets were then used to predict the prognosis of lung cancer patients., Results: We showed that an aberrant upregulation of glycolysis and oxidative phosphorylation in lung CSCs is associated with the maintenance of CSC-like features, since blocking glycolysis and oxidative phosphorylation reduces sphere formation, chemoresistance, and tumorigenicity. We also showed that the Oct4-hexokinase 2 (HK2) pathway activated by collagen XVII-laminin-332 through FAK-PI3K/AKT-GSB3β/β-catenin activation induced the upregulation of glycolysis and maintenance of CSC-like features. Finally, we showed that collagen XVII, Oct4, and HK2 could be valuable markers to predict the prognosis of lung cancer patients., Conculsions: These data suggest the Oct4-HK2 pathway regulated by collagen XVII plays an important role in metabolic reprogramming and maintenance of CSC-like features in lung CSCs, which may aid in the development of new strategies in cancer treatment.

Tumor microenvironment (TME) plays an active role in promoting tumor progression. To further understand the communication between TME and tumor cells, this study aimed at investigating the involvement of CD44, a type I cell surface receptor, in the crosstalk between tumor cells and TME. We have previously shown that chondroitin sulfate proteoglycan serglycin (SRGN), a CD44-interacting factor, was preferentially secreted by cancer-associated fibroblasts (CAFs) for promoting tumor growth in breast cancer patients. In this study, we show that SRGN is overexpressed in primary non-small cell lung cancers (NSCLCs), by both carcinoma and stromal cells. Using gain-of-function and loss-of-function approaches, we show that SRGN promotes NSCLC cell migration and invasion as well as colonization in the lung and liver in a CD44-dependent manner. SRGN induces lung cancer cell stemness, as demonstrated by its ability to enhance NSCLC cell sphere formation via Nanog induction, accompanied with increased chemoresistance and anoikis-resistance. SRGN promotes epithelial-mesenchymal transition by enhancing vimentin expression via CD44/NF-κB/claudin-1 (CLDN1) axis. In support, CLDN1 and SRGN expression are tightly linked together in primary NSCLC. Most importantly, increased expression of SRGN and/or CLDN1 predicts poor prognosis in primary lung adenocarcinomas. In summary, we demonstrate that SRGN secreted by tumor cells and stromal components in the TME promotes malignant phenotypes through interacting with tumor cell receptor CD44, suggesting that a combined therapy targeting both CD44 and its ligands in the TME may be an attractive approach for cancer therapy.

Background: The incidence of lung adenocarcinoma (LUAD) is increasing worldwide with different prognosis even in early-stage patients. We aimed to identify a prognostic panel with multiple DNA methylation biomarkers to predict survival in early-stage LUAD patients of different racial groups., Methods: The methylation array, pyrosequencing methylation assay, Cox regression and Kaplan-Meier analyses were conducted to build the risk score equations of selected probes in a training cohort of 69 Asian LUAD patients. The risk score model was verified in another cohort of 299 Caucasian LUAD patients in The Cancer Genome Atlas (TCGA) database., Results: We performed a Cox regression analysis, in which the regression coefficients were obtained for eight probes corresponding to eight genes (AGTRL1, ALDH1A3, BDKRB1, CTSE, EFNA2, NFAM1, SEMA4A and TMEM129). The risk score was derived from sum of each methylated probes multiplied by its corresponding coefficient. Patients with the risk score greater than the median value showed poorer overall survival compared with other patients (p = 0.007). Such a risk score significantly predicted patients showing poor survival in TCGA cohort (p = 0.036). A multivariate analysis was further performed to demonstrate that the eight-probe panel association with poor outcome in early-stage LUAD patients remained significant even after adjusting for different clinical variables including staging parameters (hazard ratio, 2.03; p = 0.039)., Conclusions: We established a proof-of-concept prognostic panel consisting of eight-probe signature to predict survival of early-stage LUAD patients of Asian and Caucasian populations.

Targeting tumour-initiating cells (TICs) would lead to new therapies to cure cancer. We previously demonstrated that TICs have the capacity to survive under suspension conditions, while other cells undergo anoikis. Here we show that TICs exhibit increased phosphorylation levels of S727STAT3 because of PP2A inactivation. Collagen 17 gene expression is upregulated in a STAT3-dependent manner, which also stabilizes laminin 5 and engages cells to form hemidesmosome-like junctions in response. Blocking the PP2A-S727STAT3-collagen 17 pathway inhibits the suspension survival of TICs and their ability to form tumours in mice, while activation of the same pathway increases the suspension survival and tumour-initiation capacities of bulk cancer cells. The S727STAT3 phosphorylation levels correlate with collagen 17 expression in colon tumour samples, and correlate inversely with survival. Finally, this signalling axis enhances the ability of TIC to form tumours in mouse models of malignant lung cancer pleural effusion and spontaneous colon cancer metastasis., Competing Interests: The authors declare no competing financial interests.

Growth-arrest-specific 7 (GAS7) belongs to a group of adaptor proteins that coordinate the actin cytoskeleton. Among human GAS7 isoforms, only GAS7C possesses a Src homology 3 domain. We report here that GAS7C acts as a migration suppressor and can serve as a prognostic biomarker in lung cancer. GAS7C overexpression reduces lung cancer migration, whereas GAS7C knockdown enhances cancer cell migration. Importantly, ectopically overexpressed GAS7C binds tightly with N-WASP thus inactivates the fibronectin/integrin/FAK pathway, which in turn leads to the suppression of F-actin dynamics. In addition, overexpression of GAS7C sequesters hnRNP U and thus decreases the level of β-catenin protein via the β-TrCP ubiquitin-degradation pathway. The anti-metastatic effect of GAS7C overexpression was also confirmed using lung cancer xenografts. Our clinical data indicated that 23.6% (25/106) of lung cancer patients showed low expression of GAS7C mRNA which correlated with a poorer overall survival. In addition, low GAS7C mRNA expression was detected in 60.0% of metastatic lung cancer patients, indicating an association between low GAS7C expression and cancer progression. A significant inverse correlation between mRNA expression and promoter hypermethylation was also found, which suggests that the low level of GAS7C expression was partly due to promoter hypermethylation. Our results provide novel evidence that low GAS7C correlates with poor prognosis and promotes metastasis in lung cancer. Low GAS7C increases cancer cell motility by promoting N-WASP/FAK/F-actin cytoskeleton dynamics. It also enhances β-catenin stability via hnRNP U/β-TrCP complex formation. Therefore, GAS7C acts as a metastasis suppressor in lung cancer.

Overexpression of Oct4, a stemness gene encoding a transcription factor, has been reported in several cancers. However, the mechanism by which Oct4 directs transcriptional program that leads to somatic cancer progression remains unclear. In this study, we provide mechanistic insight into Oct4-driven transcriptional network promoting drug-resistance and metastasis in lung cancer cell, animal and clinical studies. Through an integrative approach combining our Oct4 chromatin-immunoprecipitation sequencing and ENCODE datasets, we identified the genome-wide binding regions of Oct4 in lung cancer at promoter and enhancer of numerous genes involved in critical pathways which promote tumorigenesis. Notably, PTEN and TNC were previously undefined targets of Oct4. In addition, novel Oct4-binding motifs were found to overlap with DNA elements for Sp1 transcription factor. We provided evidence that Oct4 suppressed PTEN in an Sp1-dependent manner by recruitment of HDAC1/2, leading to activation of AKT signaling and drug-resistance. In contrast, Oct4 transactivated TNC independent of Sp1 and resulted in cancer metastasis. Clinically, lung cancer patients with Oct4 high, PTEN low and TNC high expression profile significantly correlated with poor disease-free survival. Our study reveals a critical Oct4-driven transcriptional program that promotes lung cancer progression, illustrating the therapeutic potential of targeting Oc4 transcriptionally regulated genes., (© The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Tumors are influenced by a microenvironment rich in inflammatory cytokines, growth factors and chemokines, which may promote tumor growth. Interleukin-6 (IL-6) is a multifunctional cytokine and known as a regulator of immune and inflammation responses. IL-6 has also been reported to be associated with tumor progression and chemoresistance in different types of cancers. In our study, we demonstrated that IL-6 enriches the properties of lung cancer stem-like cells in A549 lung cancer cells cultured in spheroid medium. IL-6 also promotes sphere formation and stem-like properties of A549 cells by enhancing cell proliferation. Methylation-specific polymerase chain reaction (PCR) was performed and revealed that IL-6 increased methylation of p53 and p21 in A549 cancer cells. Western blot analysis and quantitative real-time PCR demonstrated that IL-6 increased the expression of DNA methyltransferase 1 (DNMT1) in A549 cells cultured in spheroid medium, but not the expression of DNMT3a or DNMT3b. Knockdown of DNMT1 eliminated IL-6-mediated hypermethylation of cell cycle regulators and enrichment of lung cancer stem-like properties. In conclusion, our study, for the first time, shows that the IL-6/JAK2/STAT3 pathway upregulates DNMT1 and enhances cancer initiation and lung cancer stem cell (CSC) proliferation by downregulation of p53 and p21 resulting from DNA hypermethylation. Upon blockage of the IL-6/JAK2/STAT3 pathway and inhibition of DNMT1, the proliferation of lung CSCs was reduced and their formation of spheres and ability to initiate tumor growth were decreased. These data suggest that targeting of the IL-6/JAK2/STAT3 signaling pathway and DNMT1 may become important strategies for treating lung cancer., (© 2014 UICC.)

Rab small GTPases are master regulators of membrane trafficking and guide vesicle targeting. Recent publications show that Rab-controlled trafficking pathways are altered during tumorigenesis. However, whether any of the Rabs plays a metastasis suppressor role is least explored. Here we address the metastasis suppressive function of human Rab37 (hRAB37) using secretomics, cell, animal and clinical analyses. We show that tissue inhibitor of metalloproteinase 1 (TIMP1), a secreted glycoprotein that inhibits extracellular matrix turnover, is a novel cargo of hRAB37. hRAB37 regulates the exocytosis of TIMP1 in a nucleotide-dependent manner to inactivate matrix metalloproteinase 9 (MMP9) migration axis in vitro and in vivo. Dysfunction of hRAB37 or TIMP1 abrogates metastasis suppression. Lung cancer patients with metastasis and poor survival show low hRAB37 protein expression coinciding with low TIMP1 in tumours. Our findings identify hRAB37 as a novel metastasis suppressor Rab that functions through the TIMP1-MMP9 pathway and has significant prognostic power.

β-catenin nuclear accumulation is frequently identified in human non-small cell lung cancer (NSCLC). The HMG-box transcription factor 1 (HBP1) is a known repressor of β-catenin transactivation. However, the role of HBP1 in relation to β-catenin nuclear accumulation has not been addressed in human cancer patients. In addition, the mechanism of HBP1 gene alteration in NSCLC remains unclear, although HBP1 mutation and gene deletion of HBP1 are reported in breast and colon cancers. Here, we demonstrate that HBP1 acts as a tumour suppressor and serves as a prognostic biomarker in NSCLC clinical and cell models. The immunohistochemistry data indicated that 30.5% (25/82) of tumours from NSCLC patients showed absence or low expression of HBP1 protein. A significant inverse correlation between mRNA/protein expression and promoter hypermethylation suggested that promoter hypermethylation is responsible for low expression of HBP1 in NSCLC patients. Reactivation of HBP1 expression by demethylation reagent or ectopic expression of HBP1 suppressed β-catenin transactivation. Conversely, HBP1 knockdown increased β-catenin transactivation. Importantly, preserved expression of HBP1 had a significantly protective effect on prognosis in patients with β-catenin nuclear accumulation, suggesting that low expression of HBP1 in NSCLC patients with β-catenin nuclear accumulation was one of the major determinants of prognosis. Our data from cellular and clinical models suggest that HBP1 is a suppressor of cancer progression, making it a potential prognostic predictor and therapeutic target to attenuate lung cancer progression., (© 2014 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.)

Introduction: DNA methyltransferase 3B (DNMT3B) contributes to de novo DNA methylation and its overexpression promotes tumorigenesis. However, whether DNMT3B is upregulated by transcriptional deregulation remains unclear., Methods: We studied the transcriptional repression of DNMT3B by forkhead O transcription factor 3a (FOXO3a) in lung cancer cell, animal, and clinical models., Results: The results of luciferase reporter assay showed that FOXO3a negatively regulated DNMT3B promoter activity by preferentially interacting with the binding element FOXO3a-E (+166 to +173) of DNMT3B promoter. Ectopically overexpressed FOXO3a or combined treatment with doxorubicin to induce FOXO3a nuclear accumulation further bound at the distal site, FOXO3a-P (-249 to -242) by chromatin-immunoprecipitation assay. Knockdown of FOXO3a resulted in an open chromatin structure and high DNMT3B mRNA and protein expression. Abundant FOXO3a repressed DNMT3B promoter by establishing a repressed chromatin structure. Note that FOXO3a is a degradation substrate of MDM2 E3-ligase. Cotreatment with doxorubicin and MDM2 inhibitor, Nutlin-3, further enforced abundant nuclear accumulation of FOXO3a resulting in decrease expression of DNMT3B leading to synergistic inhibition of tumor growth and decrease of methylation status on tumor suppressor genes in xenograft specimens. Clinically, lung cancer patients with DNMT3B high, FOXO3a low, and MDM2 high expression profile correlated with poor prognosis examined by immunohistochemistry and Kaplan-Meier survival analysis., Conclusions: We reveal a new mechanism that FOXO3a transcriptionally represses DNMT3B expression and this regulation can be attenuated by MDM2 overexpression in human lung cancer model. Cotreatment with doxorubicin and Nutlin-3 is a novel therapeutic strategy through epigenetic modulation.

Background: Treatment for synchronous multiple primary lung cancers (SMPLC) remains controversial. Some surgeons treat SMPLC like advanced lung cancer, whereas other surgeons treat SMPLC as separate primary lung cancers. In this study, survival of SMPLC patients and matched-stage solitary primary lung cancer (SPLC) patients after surgical treatment were compared., Methods: Prospective medical records between 2001 and 2011 were retrospectively reviewed., Results: A total of 1,995 patients underwent pulmonary resection for lung cancer in a tertiary referral center. Only 97 patients met the modified criteria of Martini and Melamed for SMPLC. The median follow-up time was 38.3 months. The 3-year and 5-year overall survival rates were 83.1% and 69.6%, respectively. In the univariate analysis, males, smokers, and tumor size greater than 3 cm demonstrated significantly worse survival. After multivariate analysis, only tumor size (p = 0.018; hazard ratio 3.199) was identified as an independent predictor of survival. In addition, there was no significant difference in overall survival between the matched-stage SMPLC and SPLC without mediastinal lymph node involvement. Subgroup analysis in the multiple synchronous adenocarcinoma (n = 78) group demonstrated no significant difference between similar and different comprehensive histologic subtyping with respect to overall survival (61.3% versus 68.8%, p = 0.474)., Conclusions: The surgical results for SMPLC were compatible and acceptable with those for SPLC even with similar histologic subtyping, instead of T4 or M1 stages in the current TNM classification system. Preoperatively, tumor size was the only independent prognostic factor for SMPLC with surgical intervention., (Copyright © 2013 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: High-resolution computed tomography (HRCT) has become increasingly popular recently and more pulmonary ground-glass opacities (GGOs) are being identified. However, the treatment for these GGOs remains controversial. The purpose of this study was to retrospectively review the clinical and pathological characteristics and to demonstrate the longterm surgical outcomes in patients undergoing resection for GGOs in our institute., Methods: From January 2004 to December 2008, we enrolled 50 patients undergoing resection for solitary pulmonary GGOs of 3 cm or less at Taipei Veterans General Hospital. Patients with a past history of lung cancer, or multiple GGOs at presentation, or GGOs accompanied by a solid component of more than 50 percent were excluded. The patients were retrospectively reviewed and the rate and circumstances of survival were analyzed., Results: Of the 50 patients, 43 (86%) patients underwent surgery immediately after the GGO lesions were detected by the initial HRCT. Forty-six (92.0%) patients were diagnosed with lung cancer. Of this group, there were 8 (17.4%) adenocarcinomas with lepidic predominant pattern, 13 (28.3%) adenocarcinomas with acinar predominant pattern, and 24 (52.2%) adenocarcinomas with papillary predominant pattern. There was one adenocarcinoma that was mixed with small cell carcinoma. There was no surgical mortality overall, and the 5-year overall and disease-specific survival rates were 97.5% and 100%, respectively., Conclusion: The percentage of malignancy is high in pulmonary GGOs. Surgery results in an excellent prognosis in these patients., (Copyright © 2013. Published by Elsevier B.V.)

Background: Previously, we identified a sequence variant (N375S) of c-Met gene, however, its association with lung cancer risk and prognosis remain undefined., Patients and Methods: We investigated the genotype distribution of the c-Met-N375S sequence variant in 206 lung cancer patients and 207 non-cancer controls in the Taiwanese population by DNA sequencing., Results: Lung cancer patients with variant A/G and G/G genotypes showed 1.08-fold increased cancer risk when compared to patients with the wild-type A/A genotype (95% CI, 0.60-1.91). There were no significant differences in postoperative survival between c-Met-N375S and wild-type patients. In the cell model, the c-Met-N375S cells showed a decrease in cell death upon treatment with MET inhibitor SU11274 compared to wild-type cells., Conclusion: Our data suggest that the c-Met-N375S sequence variant may not play a significant role in cancer susceptibility and the prognosis of lung cancer patients. The correlation with chemoresponse of c-Met-N375S is worth further investigation in patients receiving MET therapy.

Mesenchymal stem cells (MSC) are strongly associated with tumor progression and have been used as novel cell-based agents to deliver anticancer drugs to tumors. However, controversies about the direct involvement of MSCs in tumor progression suggest that MSCs mediate tumor progression in a cancer type-dependent manner. In this report, we analyzed the functional interactions between human MSCs and lung adenocarcinoma (LAC) cells to determine the therapeutic potential of MSCs in lung cancer. We showed that MSCs effectively inhibited the migration, invasion, and cell-cycle progression of several LAC cell lines. MSCs also enhanced the mesenchymal-epithelial transition (MET) pathway, as evidenced by the reduction of several epithelial-mesenchymal transition-related markers in LAC cells cocultured with MSCs or in MSC-conditioned medium (MSC-CM). By cytokine array analysis, we determined that Oncostatin M (OSM), a differentiation-promoting cytokine, was elevated in the MSC-CM derived from primary MSC cultures. Furthermore, OSM treatment had the same effects as MSC-CM on LAC, whereas neutralizing antibodies to OSM reversed them. Notably, short hairpin RNAs against STAT1, an important downstream target of OSM, hindered the OSM-dependent induction of MET. In vivo xenograft tumor studies indicated that OSM inhibited tumor formation and metastasis of LAC cells, whereas neutralizing OSM in the MSC-CM hampered its inhibitory effects. In conclusion, this study showed that OSM is a paracrine mediator of MSC-dependent inhibition of tumorigenicity and activation of MET in LAC cells. These effects of OSM may serve as a basis for the development of new drugs and therapeutic interventions targeting cancer cells., (©2012 AACR.)

Our previous array-comparative genomic hybridization study showed that PAFAH1B1 gene locus was amplified in lung cancer patients, suggesting that PAFAH1B1 is a potential oncogene in lung cancer. Here, we investigate the oncogenic mechanisms of PAFAH1B1 in lung cancer. PAFAH1B1 was characterized in cell and animal models of lung cancer by in vitro migration and invasion assays and in vivo metastasis studies. The mRNA and protein expression levels of PAFAH1B1 were further determined and the prognostic effects of PAFAH1B1 overexpression in lung cancer patients were analyzed. Overexpression of PAFAH1B1 enhanced migration and invasion in lung cancer cells, whereas knockdown of PAFAH1B1 decreased cell migration and invasion, and disrupted cell microtubule organization and pericellular poly-fibronectin assemblies. In vivo tumor metastasis assay confirmed that PAFAH1B1 knockdown in lung cancer cells markedly reduced their metastasis capabilities in animals. The frequencies of overexpressed PAFAH1B1 mRNA and protein were 62.4% (63/101) and 57.4% (58/101) in lung cancer patients, respectively. The clinical correlation results showed that overexpression of PAFAH1B1 was significantly associated with late stage (mRNA: P=0.008, protein: P=0.008) and poor survival in lung adenocarcinoma (P=0.020) and male patients (P=0.049). Our results provide the first evidence that PAFAH1B1 overexpression contributes to lung tumorigenesis and poor prognosis. These effects are partly mediated through disruption of microtubule network and pericellular poly-fibronectin assembly to promote migration and invasiveness of lung cancer cells., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Purpose: Overexpression of DNA 5'-cytosine-methyltransferase 3A (DNMT3A), which silences genes including tumor suppressor genes (TSG), is involved in many cancers. Therefore, we examined whether the transcriptional deregulation of RB/MDM2 pathway was responsible for DNMT3A overexpression and analyzed the therapeutic potential of MDM2 antagonist for reversing aberrant DNA methylation status in lung cancer., Experimental Design: The regulation of DNMT3A expression and TSG methylation status by RB/MDM2 was assessed in cancer cell lines and patients. The effects of Nutlin-3, an MDM2 antagonist, on tumor growth in relation to DNMT3A expression and TSG methylation status were examined by xenograft model., Results: We found that RB suppressed DNMT3A promoter activity and mRNA/protein expression through binding with E2F1 protein to the DNMT3A promoter, leading to the decrease of methylation level globally and TSG specifically. In addition, MDM2 dramatically induced DNMT3A expression by negative control over RB. In clinical study, MDM2 overexpression inversely correlated with RB expression, while positively associating with overexpression of DNMT3A in samples from patients with lung cancer. Patients with high MDM2 and low RB expression showed DNMT3A overexpression with promoter hypermethylation in TSGs. Treatment with Nutlin-3, an MDM2 antagonist, significantly suppressed tumor growth and reduced DNA methylation level of TSGs through downregulation of DNMT3A expression in xenograft studies., Conclusions: This study provides the first cell, animal, and clinical evidence that DNMT3A is transcriptionally repressed, in part, by RB/E2F pathway and that the repression could be attenuated by MDM2 overexpression. MDM2 is a potent target for anticancer therapy to reverse aberrant epigenetic status in cancers.

Background: Cancer-related genes show racial differences. Therefore, identification and characterization of DNA copy number alteration regions in different racial groups helps to dissect the mechanism of tumorigenesis., Methods: Array-comparative genomic hybridization (array-CGH) was analyzed for DNA copy number profile in 40 Asian and 20 Caucasian lung cancer patients. Three methods including MetaCore analysis for disease and pathway correlations, concordance analysis between array-CGH database and the expression array database, and literature search for copy number variation genes were performed to select novel lung cancer candidate genes. Four candidate oncogenes were validated for DNA copy number and mRNA and protein expression by quantitative polymerase chain reaction (qPCR), chromogenic in situ hybridization (CISH), reverse transcriptase-qPCR (RT-qPCR), and immunohistochemistry (IHC) in more patients., Results: We identified 20 chromosomal imbalance regions harboring 459 genes for Caucasian and 17 regions containing 476 genes for Asian lung cancer patients. Seven common chromosomal imbalance regions harboring 117 genes, included gain on 3p13-14, 6p22.1, 9q21.13, 13q14.1, and 17p13.3; and loss on 3p22.2-22.3 and 13q13.3 were found both in Asian and Caucasian patients. Gene validation for four genes including ARHGAP19 (10q24.1) functioning in Rho activity control, FRAT2 (10q24.1) involved in Wnt signaling, PAFAH1B1 (17p13.3) functioning in motility control, and ZNF322A (6p22.1) involved in MAPK signaling was performed using qPCR and RT-qPCR. Mean gene dosage and mRNA expression level of the four candidate genes in tumor tissues were significantly higher than the corresponding normal tissues (P<0.001~P=0.06). In addition, CISH analysis of patients indicated that copy number amplification indeed occurred for ARHGAP19 and ZNF322A genes in lung cancer patients. IHC analysis of paraffin blocks from Asian Caucasian patients demonstrated that the frequency of PAFAH1B1 protein overexpression was 68% in Asian and 70% in Caucasian., Conclusions: Our study provides an invaluable database revealing common and differential imbalance regions at specific chromosomes among Asian and Caucasian lung cancer patients. Four validation methods confirmed our database, which would help in further studies on the mechanism of lung tumorigenesis.

The high invasiveness and frequent recurrence of lung adenocarcinoma (LAC) are major reasons for treatment failures and poor prognoses. Alterations in microRNAs (miRNAs) expression have been shown in lung cancers. Recent reports have demonstrated that tumors contain a small subpopulation of cancer stem cells (CSCs) that possesses self-renewing capacity and is responsible for tumor malignancy including metastasis, relapse, and chemoradioresistance. However, a miRNAs-based therapeutic approach in LAC-associated CSCs (LAC-CSCs) is still blurred. Using miRNA/mRNA-microarray and Quantitative RT-PCR, we found that the expression of miR145 is negatively correlated with the levels of Oct4/Sox2/Fascin1 in LAC patient specimens, and an Oct4(high)Sox2(high)Fascin1(high)miR145(low) phenotype predicted poor prognosis. We enriched LAC-CSCs by side population sorting or identification of CD133 markers and found that LAC-CSCs exhibited low miR145 and high Oct4/Sox2/Fascin1 expression, CSC-like properties, and chemoradioresistance. To clarify the role of miR145, we used a polyurethane-short branch-polyethylenimine (PU-PEI) as the vehicle to deliver miR145 into LAC-CSCs. PU-PEI-mediated miR145 delivery reduced CSC-like properties, and improved chemoradioresistance in LAC-CSCs by directly targeting Oct4/Sox2/Fascin1. Importantly, the repressive effect of miR145 on tumor metastasis was mediated by inhibiting the epithelial-mesenchymal transdifferentiation (EMT) and metastastic ability, partially by regulating Oct4/Sox2/Fascin1, Tcf4, and Wnt5a. Finally, in vivo study showed that PU-PEI-mediated miR145 delivery to xenograft tumors reduced tumor growth and metastasis, sensitized tumors to chemoradiotherapies, and prolonged the survival times of tumor-bearing mice. Our results demonstrated that miR145 acts as a switch regulating lung CSC-like and EMT properties, and provide insights into the clinical prospect of miR145-based therapies for malignant lung cancers., (Crown Copyright © 2012. Published by Elsevier B.V. All rights reserved.)

Background: The role of mesenchymal stem cells (MSCs) and IL-6 in lung cancer has not been well-addressed. We aimed to determine if MSCs can enhance the ability of tumor initiation of lung cancer cells, and link MSCs with activation of the IL-6/JAK2/STAT3 signaling pathway., Materials and Methods: Lung cancer cell lines A549 and CL1-5 were directly or indirectly cocultured with MSCs. Spheres were defined as cell colonies with >50% area showing 3-dimensional structure and blurred cell margins. Cells without and with MSCs were injected into NOD/SCID mice. The percentage of tumor formation was determined. The influence of the IL-6/JAK2/STAT3 signaling pathway in cancer cell sphere formation and tumor growth were investigated., Results: A very small number of lung cancer cells, when mixed with otherwise non-tumorigenic MSCs, obtained de novo tumorigenicity when injected subcutaneously and allowed to form a tumor xenograft. Secretion of IL-6 from MSCs increased activation of the JAK2/STAT3 pathway in cancer cells, and enhanced sphere formation and tumor initiation. A reduced capacity of tumor formation of A549 and CL1-5 lung cancer cells when IL-6 was inhibited in MSCs or STAT3 was silenced in A549 and CL1-5 admixed with MSCs., Conclusions: Culture of A549 or CL1-5 lung cancer cells with MSCs increased sphere formation, drug resistance, and overexpression of pluripotency markers through activation of the IL-6/JAK2/STAT3 pathway. MSCs enhanced the capability of A549 and CL1-5 lung cancer cells to form tumors in immunodeficient mice. Blockade of the IL-6/JAK2/STAT3 pathway attenuated the capability of A549 and CL1-5 cells to form tumors., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Mounting evidence links cancers possessing stem-like properties with worse prognosis. Network biology with signal processing mechanics was explored here using expression profiles of a panel of tumor stem-like cells (TSLCs). The profiles were compared to their parental tumor cells (PTCs) and the human embryonic stem cells (hESCs), for the identification of gene chromobox homolog 5, CBX5, as a potential target for lung cancer. CBX5 was found to regulate the stem-like properties of lung TSLCs and was predictive of lung cancer prognosis. The investigation was facilitated by finding target genes based on modeling epistatic signaling mechanics via a predictive and scalable network-based survival model. Topologically-weighted measurements of CBX5 were synchronized with those of BIRC5, DNMT1, E2F1, ESR1, MLH1, MSH2, RB1, SMAD1 and TAF5. We validated our findings in another Taiwanese lung cancer cohort, as well as in knockdown experiments using sh-CBX5 RNAi both in vitro and in vivo.

Background: Signal transducer and activator of transcription 3 (STAT3) signaling reportedly promotes tumor malignancy and recurrence in nonsmall cell lung cancer (NSCLC). It was demonstrated previously that the STAT3 pathway maintains the tumorigenicity and therapeutic resistance of malignant tumors as well as cancer stem cells (CSCs). The objective of the current study was to investigate the effect of the strong STAT3 inhibitor, cucurbitacin I, in prominin-1 (CD133)-positive lung cancer cells., Methods: CD133-positive and CD133-negative NSCLC-derived cells were isolated from 7 patients with NSCLC. CD133-positive NSCLC cells that were treated with or without cucurbitacin I were evaluated for their expression of phosphorylated STAT3 (p-STAT3), tumorigenicity, stemness properties, and resistance to chemotherapeutic drugs and ionizing radiation., Results: Compared with parental or CD133-negative NSCLC cells, CD133-positive NSCLC cells had greater tumorigenicity, greater radioresistance, and higher expression of octamer-binding transcription factor 4 (Oct-4), Nanog homeobox, and sex-determining region Y, box 2 (Sox2) at high p-STAT3 levels. Cucurbitacin I treatment at 100 nM effectively abrogated STAT3 activation, tumorigenic capacity, sphere formation ability, radioresistance, and chemoresistance in CD133-positive NSCLC cells. Microarray data suggested that cucurbitacin I inhibited the stemness gene signature of CD133-positive NSCLC cells and facilitated the differentiation of CD133-positive NSCLC cells into CD133-negative NSCLC cells. It is noteworthy that 150 nM cucurbitacin I effectively blocked STAT3 signaling and downstream survival targets, such as B-cell chronic lymphocytic leukemia/lymphoma 2 (Bcl-2) and Bcl-2-like 1 (Bcl-xL) expression and induced apoptosis in CD133-positive NSCLC cells. Finally, xenotransplantation experiments revealed that cucurbitacin I plus radiotherapy or chemotherapeutic drugs significantly suppressed tumorigenesis and improved survival in NSCLC-CD133-positive-transplanted, immunocompromised mice., Conclusions: Targeting STAT3 signaling in CD133-positive NSCLC cells with cucurbitacin I suppressed CSC-like properties and enhanced chemoradiotherapy response. The potential of cucurbitacin I should be verified further in future anti-CSC therapy., (Copyright © 2011 American Cancer Society.)

Objective: This study assessed the sensitivity of helical computed tomography in the detection of pulmonary metastases in patients with colorectal cancer and the role of video-assisted thoracoscopic surgery in patients with pulmonary metastases., Methods: A total of 120 operations for pulmonary metastases were performed in 91 patients with colorectal cancer. All patients received an open thoracotomy that allowed full operative inspection and palpation. Clinical data, including the size and number of pulmonary metastasis, were retrospectively collected. The difference in the number of pulmonary metastases as determined by computed tomography scan and surgical findings was determined and analyzed., Results: Operative findings were consistent with the preoperative computed tomography scan reports in 64 of the 120 operations (53.3%). In 32 operations (26.7%), additional metastatic tumors were identified at open thoracotomy. The sensitivity of helical computed tomography in the detection of colorectal cancer metastatic lesions ranged from 35.5% to 95.5%. Unilateral solitary lesion demonstrated on computed tomography scan was an independent factor for the prediction of additional metastatic lesions (P = .023)., Conclusions: The sensitivity of helical computed tomography scan in the detection of pulmonary metastases can reach 95.5% in patients with colorectal cancer with a solitary metastatic lesion. A unilateral solitary lesion demonstrated on preoperative computed tomography scan is an independent factor for prediction of additional metastatic lesions. If feasible, video-assisted thoracoscopic surgery may be justified in patients with colorectal cancer with solitary pulmonary metastases., (Copyright © 2011 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.)

The p53 tumor suppressor exerts its function mainly as a transcriptional activator. Here we show that the Ras-related small GTPase Rad, an inhibitor of Rho kinase, is a direct transcriptional target of p53. Expression of Rad messenger RNA (mRNA) and protein was induced by DNA damage in a p53-dependent manner. The -2934/-2905-bp Rad promoter region, to which p53 bound, was required for p53-mediated Rad gene activation. Treatment by DNA damaging agents increased p53 occupancy and histone acetylation in the region of Rad promoter containing the p53-binding site. Expression of Rad diminished the inhibitory phosphorylation at Ser3 of cofilin, a regulator of actin dynamics, and suppressed migration and invasiveness of cancer cells. Knockdown of Rad promoted cell migration and alleviated the p53-mediated migration suppression. Frequent loss of Rad mRNA and protein expression was observed in non-small cell lung carcinoma tissues. Together our results reveal a mechanism that p53 may inhibit cell migration by disrupting actin dynamics via Rad activation and implicate a tumor suppressor role of Rad in lung cancer.

Background: In the current study, the authors sought to identify the molecular mechanisms underlying the chemoresistance of lung cancer stem or initiation cells (cancer stem cells)., Methods: A549 lung cancer cells before and after selective enrichment of a subpopulation of cancer stem cells were treated with superoxide and traditional chemotherapeutics to determine their sensitivity or resistance to these cytotoxic agents. Apoptotic activity was measured using a variety of fluorescence-based and biochemical techniques. Specific pathways involved in the chemoresistance of cancer stem cell-enriched lung cancer cells were analyzed with Western blotting and pharmacologic targeting therapy in a xenograft model., Results: Lung cancer stem cells exhibited significantly decreased apoptotic response to treatment with superoxide, cisplatin, gemcitabine, or a combination of cisplatin and gemcitabine compared with control A549 cells. Apoptotic resistance was mediated through the inactivation of caspase-9 and caspase-3. Increased activation of p38MAPK, MAPKAPK2, and Hsp27 was observed in lung cancer stem cells compared with control A549 cells both before and after exposure to superoxide and chemotoxic agents. In a mouse model of lung cancer, chemotherapy-induced cells increased in the antiapoptosis pathway, and quercetin, an inhibitor of Hsp27, combined with traditional chemotherapy was effective in blocking the pathway and in the treatment of lung tumors in vivo., Conclusions: The authors' data demonstrate that lung cancer stem cells have elevated levels of activated Hsp27 upon treatment with superoxide and traditional chemotherapy. When combined with chemotoxic agents, blockage of Hsp27 decreased the survival of lung cancer stem cells, which otherwise were resistant to traditional chemotherapy., (Copyright © 2010 American Cancer Society.)

Epithelial-mesenchymal transition (EMT), a critical process of cancer invasion and metastasis, is associated with stemness property of cancer cells. Though Oct4 and Nanog are homebox transcription factors essential to the self-renewal of stem cells and are expressed in several cancers, the role of Oct4/Nanog signaling in tumorigenesis is still elusive. Here microarray and quantitative real-time PCR analysis showed a parallel, elevated expression of Oct4 and Nanog in lung adenocarcinoma (LAC). Ectopic expressions of Oct4 and Nanog in LACs increased the percentage of CD133-expressing subpopulation and sphere formation, enhanced drug resistance, and promoted EMT. Ectopic expressions of Oct4 and Nanog activated Slug and enhanced the tumor-initiating capability of LAC. Furthermore, double knockdown of Oct4 and Nanog suppressed the expression of Slug, reversed the EMT process, blocked the tumorigenic and metastatic ability, and greatly improved the mean survival time of transplanted immunocompromised mice. The immunohistochemical analysis demonstrated that expressions of Oct4, Nanog, and Slug were present in high-grade LAC, and triple positivity of Oct4/Nanog/Slug indicated a worse prognostic value of LAC patients. Our results support the notion that the Oct4/Nanog signaling controls epithelial-mesenchymal transdifferentiation, regulates tumor-initiating ability, and promotes metastasis of LAC., (©2010 AACR.)

Background: The aim of this study is to evaluate the prognostic significance of preoperative and postoperative serum carcinoembryonic antigen (CEA) levels in patients with stage I non-small-cell lung cancer., Material and Methods: A retrospective review of the medical records of 257 patients with stage I lung cancer undergoing surgical resection was performed. The clinical data of each patient was collected for analysis including age, smoking habits, gender, preoperative and postoperative serum CEA levels, tumor diameter, histologic type, visceral pleural invasion, pathologic stage, and type of operation., Results: Adenocarcinoma was more often associated with elevated preoperative CEA level compared with non-adenocarcinoma. Tumor histology, however, did not influence postoperative CEA levels. In the univariate analysis, age, serum CEA level, and pathologic stage were prognostic factors. Patients with normal preoperative serum CEA levels had better 5-y survival than patients with high preoperative serum CEA levels (71.1% versus 54.6%, P = 0.016). The patients with a persistently high serum CEA level after surgery had worst prognosis. Multivariate analysis demonstrated that older age (≥65) and persistently high serum CEA levels were independent significant prognostic factors in patients with stage I lung cancer., Conclusions: Age (≥65 years) and preoperative and postoperative serum CEA levels are independent prognostic factors in patients with stage I lung cancer. Patients with a persistently high serum CEA level after surgery had worst survival, and may be good candidates for adjuvant chemotherapy., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Background and Objectives: Small-cell carcinomas (SCC) develop most commonly in the lung (small-cell lung carcinoma, SCLC) and only small percentages are present at extra-pulmonary sites. This study aimed to examine the distribution, treatment, and survival of SCCs., Methods: The records for 922 SCC cases of various origins between January 1989 and December 2008 were retrieved and analyzed., Results: The lung (89.2%) was the most common location, followed by the esophagus (1.8%), urinary bladder (1.6%), uterine cervix (1.5%), colorectum (1.4%), skin (1.0%), stomach (0.9%), head and neck (0.7%), prostate (0.3%), and small intestine (0.1%). Limited disease (LD) SCLC patients underwent surgery and chemotherapy had significantly higher survival rates than those who received chemotherapy alone, those who underwent combined radiotherapy and chemotherapy, and those who were administered supportive treatment. Actuarial 1-, 2-, and 3-year survival rate was 28.9%, 9.4%, and 4.8% for total SCLC cases, 41.3%, 17.5%, and 9.6% for LD-SCLC patients, and 21.9%, 4.2%, and 1.8% for extensive disease (ED)-SCLC patients (P < 0.001). The survival rates for lung and stomach SCC patients with LD were significantly better than for patients with ED; cervical SCC stages I and IIa patients had better survival rates than patients with stage IIb and above (P = 0.034)., Conclusion: The lung was the most common location of SCCs, with 9.3% of cases being extra-pulmonary in origin. The need for combined surgery and chemotherapy in LD-SCLC patients deserves further evaluation., (J. Surg. Oncol. 2010;102:497-502. © 2010 Wiley-Liss, Inc.)

Background: Tumor suppressor gene (TSG) RASSF1A and candidate TSG BLU are two tandem head-to-tail genes located at 3p21.3. We hypothesized that there may be a concordance on their gene expression and promoter methylation status. If not, then there may be an insulator located between RASSF1A and BLU genes that provides a barrier activity., Methodology/principal Findings: We first identified potential transcriptionally important CpG sites using the methylation-specific oligonucleotide array in relation to mRNA expression of RASSF1A and BLU genes in primary lung tumors. We demonstrated that E2F1 bound to the potential transcriptionally important CpG sites in RASSF1A gene of a normal lung cell line expressing RASSF1A transcripts, whereas loss of E2F1 binding to RASSF1A in A549 cancer cell line was the result of DNA methylation. Both RASSF1A and BLU genes had their own potential transcriptionally important CpG regions. However, there was no correlation of methylation status between RASSF1A and BLU. Using gel shift assay and chromatin immunoprecipitation-PCR (ChIP-PCR), we found that CCCTC-binding factor (CTCF) bound to insulator sequences located between these two genes. Bisulfite sequencing and ChIP-PCR revealed distinct methylation and chromatin boundaries separated by the CTCF binding domains in normal cells, whereas such distinct epigenetic domains were not observed in cancer cells. Note that demethylation reagent and histone deacetylase inhibitor treatments led to CTCF binding and recovery of barrier effect for RASSF1A and BLU genes in cancer cells., Conclusions/significance: Our study dissects the potential transcriptionally important CpG sites for RASSF1A and BLU genes at the sequence level and demonstrates that CTCF binding to the insulator of BLU gene provides a barrier activity within separate epigenetic domains of the juxtaposed BLU and RASSF1A loci in the 3p21.3 gene cluster region.

Hypermethylation-mediated tumor suppressor gene silencing plays a crucial role in tumorigenesis. Understanding its underlying mechanism is essential for cancer treatment. Previous studies on human N-alpha-acetyltransferase 10, NatA catalytic subunit (hNaa10p; also known as human arrest-defective 1 [hARD1]), have generated conflicting results with regard to its role in tumorigenesis. Here we provide multiple lines of evidence indicating that it is oncogenic. We have shown that hNaa10p overexpression correlated with poor survival of human lung cancer patients. In vitro, enforced expression of hNaa10p was sufficient to cause cellular transformation, and siRNA-mediated depletion of hNaa10p impaired cancer cell proliferation in colony assays and xenograft studies. The oncogenic potential of hNaa10p depended on its interaction with DNA methyltransferase 1 (DNMT1). Mechanistically, hNaa10p positively regulated DNMT1 enzymatic activity by facilitating its binding to DNA in vitro and its recruitment to promoters of tumor suppressor genes, such as E-cadherin, in vivo. Consistent with this, interaction between hNaa10p and DNMT1 was required for E-cadherin silencing through promoter CpG methylation, and E-cadherin repression contributed to the oncogenic effects of hNaa10p. Together, our data not only establish hNaa10p as an oncoprotein, but also reveal that it contributes to oncogenesis through modulation of DNMT1 function.

Overexpression of DNA 5'-cytosine-methyltransferases (DNMT), which are enzymes that methylate the cytosine residue of CpGs, is involved in many cancers. However, the mechanism of DNMT overexpression remains unclear. Here, we showed that wild-type p53 negatively regulated DNMT1 expression by forming a complex with specificity protein 1 (Sp1) protein and chromatin modifiers on the DNMT1 promoter. However, the stoichiometry between p53 and Sp1 determined whether Sp1 acts as a transcription activator or corepressor. Low level of exogenous Sp1 enhanced the repressive activity of endogenous p53 on the DNMT1 promoter whereas high level of Sp1 upregulated DNMT1 gene expression level in A549 (p53 wild-type) cells. In H1299 (p53 null) cells, exogenous Sp1 induced DNMT1 expression in a dose-dependent manner. We also discovered a new mechanism whereby high level of Sp1, via its COOH-terminal domain, induced interaction between p53 and MDM2, resulting in degradation of p53 by MDM2-mediated ubiquitination. Clinical data from 102 lung cancer patients indicated that overexpression of DNMT1 was associated with p53 mutation (P = 0.014) and high expression of Sp1 protein (P = 0.006). In addition, patients with overexpression of both DNMT1 and Sp1 proteins showed poor prognosis (P = 0.037). Our cell and clinical data provided compelling evidence that deregulation of DNMT1 is associated with gain of transcriptional activation of Sp1 and/or loss of repression of p53. DNMT1 overexpression results in epigenetic alteration of multiple tumor suppressor genes and ultimately leads to lung tumorigenesis and poor prognosis., ((c)2010 AACR.)

DNA methyltransferase 1 (DNMT1) catalyzes DNA methylation and is overexpressed in many human diseases, including cancer. The tobacco-specific carcinogen NNK also induces DNA methylation. However, the role of DNMT1-mediated methylation in tobacco carcinogenesis remains unclear. Here we used human and mouse lung cancer samples and cell lines to determine a mechanism whereby NNK induced DNMT1 expression and activity. We determined that in a human lung cell line, glycogen synthase kinase 3beta (GSK3beta) phosphorylated DNMT1 to recruit beta-transducin repeat-containing protein (betaTrCP), resulting in DNMT1 degradation, and that NNK activated AKT, inhibiting GSK3beta function and thereby attenuating DNMT1 degradation. NNK also induced betaTrCP translocation to the cytoplasm via the heterogeneous nuclear ribonucleoprotein U (hnRNP-U) shuttling protein, resulting in DNMT1 nuclear accumulation and hypermethylation of the promoters of tumor suppressor genes. Fluorescence immunohistochemistry (IHC) of lung adenomas from NNK-treated mice and tumors from lung cancer patients that were smokers were characterized by disruption of the DNMT1/betaTrCP interaction and DNMT1 nuclear accumulation. Importantly, DNMT1 overexpression in lung cancer patients who smoked continuously correlated with poor prognosis. We believe that the NNK-induced DNMT1 accumulation and subsequent hypermethylation of the promoter of tumor suppressor genes may lead to tumorigenesis and poor prognosis and provide an important link between tobacco smoking and lung cancer. Furthermore, this mechanism may also be involved in other smoking-related human diseases.

Background: Non-small cell lung cancer (NSCLC) is a heterogeneous group of disorders with a number of genetic and proteomic alterations. c-CBL is an E3 ubiquitin ligase and adaptor molecule important in normal homeostasis and cancer. We determined the genetic variations of c-CBL, relationship to receptor tyrosine kinases (EGFR and MET), and functionality in NSCLC., Methods and Findings: Using archival formalin-fixed paraffin embedded (FFPE) extracted genomic DNA, we show that c-CBL mutations occur in somatic fashion for lung cancers. c-CBL mutations were not mutually exclusive of MET or EGFR mutations; however they were independent of p53 and KRAS mutations. In normal/tumor pairwise analysis, there was significant loss of heterozygosity (LOH) for the c-CBL locus (22%, n = 8/37) and none of these samples revealed any mutation in the remaining copy of c-CBL. The c-CBL LOH also positively correlated with EGFR and MET mutations observed in the same samples. Using select c-CBL somatic mutations such as S80N/H94Y, Q249E and W802* (obtained from Caucasian, Taiwanese and African-American samples, respectively) transfected in NSCLC cell lines, there was increased cell viability and cell motility., Conclusions: Taking the overall mutation rate of c-CBL to be a combination as somatic missense mutation and LOH, it is clear that c-CBL is highly mutated in lung cancers and may play an essential role in lung tumorigenesis and metastasis.