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Background: Lung adenocarcinoma (LUAD) is the major form of lung cancer that presents a major peril to public health. Owing to the high rates of morbidity, mortality and chemoresistance, it is necessary to develop more effective therapeutic targets of LUAD. Mitochondrial fission regulator 1 (MTFR1) affects the occurrence and development of some diseases by regulating mitochondrial dynamics and is dysregulated in LUAD. However, the functions and molecular mechanisms of MTFR1 in LUAD have not been investigated.Methods: Immunohistochemical (IHC) analysis, real-time quantitative polymerase chain reaction (RT-qPCR), bioinformatic analysis and western blot (WB) were performed to assess the expression of MTFR1 at both protein and mRNA levels. The biological functions of MTFR1 in LUAD cells were assessed based on various in vivo and in vitro experiments. The dual-luciferase reporter assay and some rescue experiments were performed to evaluate the underlying mechanism of MTFR1 in LUAD.Results: MTFR1 was upregulated in LUAD cells and tissues and correlated with dismal clinicopathologic features and a worse prognosis of patients with LUAD. Functionally, MTFR1 overexpression stimulated the proliferation, invasion, migration and glycolytic capacity and impeded the apoptosis of LUAD cells; however, opposite results were obtained when MTFR1 expression was knocked down. MTFR1, which was directly targeted by miR-29c-3p, may exert its biological functions through the AMPK/mTOR signalling pathway.Conclusion: MTFR1 promotes the progression of LUAD. Therefore, targeting MTFR1 can offer an effective therapeutic strategy for LUAD treatment.

Background: Many evidences proved important roles of microRNAs in the occurrence and development of non-small cell lung cancer (NSCLC). This work aimed to explore the effects and regulating mechanism of microRNA-665 (miR-665) in NSCLC. Methods: Here, quantitative real time PCR was used to evaluate the expression level of miR-665 in NSCLC tissues and several cell lines (H520, H1299, PC9, H358, and A549). Then, MTT, apoptosis assays and wound-healing assays were performed to study miR-665 functions on cell proliferation, apoptosis and migration. Based on bioinformatics analysis, nemo-like kinase (NLK) was predicted as a potential target of miR-665 and then a series of experiments were performed to explore miR-665 mechanism.Results: In NSCLC tissues and several cell lines, miR-665 was up-regulated and cell experiments displayed that it had abilities to promote cell proliferation and migration, and inhibit cell apoptosis. MiR-665 over-expression could reduce NLK mRNA and protein level by binding to 3′-untranslated region of NLK, which suggested that miR-665 could regulate NLK expression. Further analysis found that there was an inverse correlation f between miR-665 and NLK in NSCLC. Moreover, low-level NLK possessed same effects on cells as miR-665 over-expression, and its knockdown could partly recovery the miR-665-mediated cell proliferation, migration and anti-apoptosis, indicating that miR-665 might regulate biological behaviors of NSCLC cells via targeting NLK. Conclusion: MiR-665 probably promoted NSCLC occurrence and progression via targeting NLK, which might be a hopeful biomarker for NSCLC diagnosis or a target for treatment.

MicroRNAs (miRNAs/miRs) are a class of small, highly conserved non-coding RNAs that can serve either oncogenic or tumor-suppressive roles in a wide variety of tumors. miR-200c is a member of the miR-200 family whose specific role in non-small cell lung cancer (NSCLC) has not yet been elucidated. The purpose of the present study was to detect the expression level of miR-200c in NSCLC, and to analyze its association with clinicopathological factors and patient prognosis. The present study determined the expression levels of miR-200c in 110 tumor samples collected from patients diagnosed with NSCLC who underwent complete tumor resection with regional lymph node dissection, as assessed by reverse transcription-quantitative polymerase chain reaction. The association between the expression level of miR-200c and clinicopathological features and patient prognosis was also analyzed. The results showed that miR-200c overexpression was detected in 66 of the 110 cases and was significantly associated with positive lymph node metastasis (P

Objective. This Work is aimed at exploring the effect of microRNA (MiR)-608 on the function of nonsmall cell lung cancer (NSCLC) A549 cells and related mechanisms. Methods. Blood samples of 106 NSCLC patients (experimental group) as well as 124 normal people (control group) were selected for relevant investigation. Polymerase chain reaction (PCR) as well as DNA sequencing was used to determine the genotyping of the MiR-608 rs4919510 polymorphism. MiR-608 expression in cells was detected by real-time PCR technology. Western blotting was used to detect changes in protein levels. NSCLC tissues as well as adjacent tissues were explored in 33 patients undergoing surgery. Results. MiR-608 rs4919510 does not influence the incidence of NSCLC patients. In addition, MiR-608 expression was downregulated in the tumor tissue of NSCLC patients, while the transcription factor activating enhancer-binding protein 4 (TFAP4) expression was upregulated. MiR-608 promotes DOX- (Doxorubicin-) induced apoptosis by negatively regulating TFAP4 expression in NSCLC tissue. TFAP4 can significantly inhibit the migration of A549 cells. Conclusion. The findings in this investigation can contribute to the effective treatment of NSCLC patients. Also, the investigation can provide some theoretical support for the application of new targets for NSCLC treatment.

Background: The resection of nodules by thoracoscopic surgery is difficult because the nodules may be hard to identify. Currently, preoperative localization of pulmonary nodules is widely used in the clinic, including Computed Tomographic Imaging (CT)-guided transthoracic approach, hook-wire and coil embolization, but these methods increase radiation exposure and cause complications. Methods: In this study, we retrospectively compared electromagnetic navigation bronchoscopy (ENB) guided and CT guided localization of small pulmonary nodules before resection. Results: Total 157 patients underwent the localization procedure successfully, and the nodules were localized by CT guidance in 105 patients and by ENB in 52 patients. The nodule size of magnetic navigation localization was smaller than that of CT-guided localization (P

Background Circular RNA (circRNA) has become a new focus in the field of tumor biology research in recent years. Many circRNAs have been showed to play an important role in the progression of lung adenocarcinoma (LUAD). In this work, we studied the oncological role of hsa-circ-000881 in LUAD and attempted to explore the related mechanism. Methods The relative expressions of hsa-circ-000881, miR-665, and PRICKLE2 were detected by RT-qPCR or western blot. Functional assays were conducted to analyze the role of hsa-circ-000881 in the proliferation, migration, and invasion of LUAD cells. A luciferase reporter assay was performed to verify whether hsa-circ-000881, miR-665, and PRICKLE2 interact with each other. Results Circ-000881 was remarkably downregulated in LUAD. Overexpression of circ-000881 attenuated cell growth, migration, and invasion, whereas its knockdown enhanced the malignancy of LUAD cells. The results of luciferase reporter assay and bioinformatics analysis confirmed that circ-000881 served as a sponge for miR-665, and PRICKLE2 was a direct target of miR-665.Overexpression of miR-665 or silencing of PRICKLE2 abolished circ-000881-mediated inhibition of malignant tumor behavior in LUAD cells. Conclusions Circ-000881 has inhibitory effects on LUAD via a miR-665/PRICKLE2 axis, suggesting that circ-000881 may be an underlying therapeutic target for LUAD.

The conventional video-assisted thoracoscopic surgery (VATS) is performed through the intercostals incisions. In this study, we reported our current experience of thoracoscopic surgery using a subxiphoid single-incision and compared it with the intercostal uniport VATS in the operation time and postoperative pain for spontaneous pneumothorax.From July 2014 to September 2015, 43 consecutive patients with spontaneous pneumothorax underwent the unilateral or bilateral bullectomy vie VATS. Among these, 22 patients were treated by the subxiphoid single-incision VATS, and 21 patients were treated using the conventional intercostals uniport VATS. The duration of operation, hospital stay days and inpatient pain scores were compared between each group.The postoperative pain scores on postoperative days (POD) 0, 1, 2 and 3 were significantly lower for patients who underwent the subxiphoid single-incision VATS than those who underwent the intercostal uniport VATS (p 0.05). However, the subxiphoid single-incision VATS needed longer surgical time than the intercostal uniport VATS (p 0.001).The subxiphoid uniport VATS could decrease the postoperative pain and was safe and effective for performing the unilateral or bilateral bullectomy, but, demanded longer surgical time comparing with the intercostal uniport VATS.Subxiphoid single-incision VATS, as a new method for bullectomy, could provide a good choice of the incision position for these young patients with spontaneous pneumothorax.

Reactive oxygen species (ROS) are at the center of many physiological and pathological processes. ROS generated due to oxidative stress can potentiate both cancer initiation and progression. Rotenone, which is an inhibitor of the mitochondrial electron transport chain complex I, results in the activation of NOX2 and release of ROS, and has been shown to display anticancer activity through the induction of apoptosis in various cancer cells. The mechanistic link between rotenone-dependent activation of NOX2 and induction of apoptosis is still elusive. In this study, we used the human lung cancer A549 cells to study the molecular mechanism(s) involved between rotenone-dependent activation of NOX2 and impairment of autophagic machinery. We report that acute exposure to rotenone induced mild NOX2-dependnet oxidative stress, which impaired the autophagic flux, resulting in cytosolic accumulation of LC3 and p62/STSQM1. We further show that this induction occurs through the PI3K/Akt/mTORC1 signaling pathway. We furthermore show that chronic exposure to rotenone lead to excessive NOX2-dependent ROS generation, increases autophagy, and decreases p62 level via increased-autophagic flux. Taken together, this study is the first mechanistic elucidation of how rotenone can be used to potently target cancer cells without overhauling the entire cellular machinery. © 2016 IUBMB Life 68(5):388-393, 2016.

MicroRNAs (miRs) serve important roles in various human cancers, including lung adenocarcinoma. Exploring the function and regulatory mechanism of miRs underlying lung adenocarcinoma progression may contribute to identifying novel therapeutic targets and candidates. The present study aimed to examine miR-148a expression and investigate the molecular mechanisms of miR-148a in lung adenocarcinomas. The data from the current study indicated that miR-148a was significantly downregulated in lung adenocarcinoma tissues and cell lines, and low miR-148a expression was significantly associated with advanced Tumor, Node, Metastasis stages and lymph node metastasis, as well as the shorter survival time of patients. Increased miR-148a expression markedly decreased the cell proliferation, colony formation and cell cycle progression of H23 and H1975 cells. Transcription factor E2F3 (E2F3) was identified as a target of miR-148a in H23 and H1975 cells. The expression of E2F3 was negatively mediated by miR-148a in H23 and H1975 cells. In addition, E2F3 was significantly upregulated in lung adenocarcinoma tissues and cell lines, and the expression of miR-148a was inversely correlated with E2F3 expression in lung adenocarcinoma tissues. Additional experiments demonstrated that increased E2F3 expression counteracted the inhibitory effects on lung adenocarcinoma cells caused by miR-148a overexpression. In summary, the findings of the current study suggest that miR-148a may have suppressive effects on the proliferation of lung adenocarcinoma cells at least in part through directly targeting E2F3. Therefore, miR-148a may be used as a potential candidate for the treatment of lung adenocarcinoma.

Although ~80% of newly diagnosed pediatric patients with acute lymphoblastic leukemia (ALL) become disease‑free following appropriate treatment, relapses frequently occur, with dismal prognosis. Therefore, it is urgent to develop novel therapeutic modalities. Resistance to chemotherapy is a major obstacle for the treatment of relapsed ALL. It has been indicated that Wnt pathway is potentially associated with leukemia recurrence. In the current study, a vincristine (VCR)‑resistant variant of the human ALL cell line BALL‑1 (BALL‑1/VCR) that also had relatively specific resistance to both doxorubicin and etoposide was generated. Over‑activation of the Wnt/β‑catenin signaling pathway was observed in BALL‑1/VCR cells, whereas Dickkopf‑related protein 1 selectively suppressed the Wnt signaling pathway and sensitized the response of BALL‑1/VCR to anticancer agents. In addition, prednisolone exposure in combination with Wnt inhibition restored chemo‑sensitivity in relapsed ALL blasts. Since the resistance of BALL‑1/VCR cells is potentially attributed to the overexpression of MDR‑associated protein 1 (MRP1), the development of drug resistance in relapsed ALL may associated with the overexpression of MRP1 and P‑glycoprotein. The results of this study demonstrated that, as a potential candidate to mimic relapsed ALL, BALL‑1/VCR could be used in further research, while Wnt‑inhibition may become a promising therapeutic approach for treating ALL.

Lysosome-associated protein transmembrane-4β (LAPTM4B) is a novel cancer-related gene that is upregulated in many tumors, and which plays important roles in carcinogenesis. It has two alleles, LAPTM4B 1 and LAPTM4B 2. LAPTM4B 1 contains only one copy of a 19-bp sequence in the first exon, whereas LAPTM4B 2 contains two tight tandem segments. Previous studies have shown that LAPTM4B 2 is a risk factor for susceptibility and prognosis of many tumors. The present study investigated the relationship between LAPTM4B polymorphism and non-small cell lung cancer (NSCLC) susceptibility and prognosis. We identified LAPTM4B genotypes with polymerase chain reaction (PCR) in peripheral blood samples. In the adjusted multivariate logistic regression analysis, we found that LAPTM4B 1/2, LAPTM4B 2/2 exhibited 1.48-fold [95% confidence interval (CI), 1.076-2.037] and 2.855-fold (95%CI, 1.722-4.734) increases in the risk of developing NSCLC compared with non-LAPTM4B 2 carriers. Furthermore, our results showed that overall survival time and disease-free survival time of patients with LAPTM4B 2 were significantly shorter than in patients carrying LAPTM4B 1 (P=0.001 and P=0.001, respectively). In addition, multivariate Cox regression analysis revealed that LAPTM4B 2 was also an independent prognostic factor for NSCLC. These results suggest that LAPTM4B polymorphisms may be a prospective marker for evaluating the risk and prognosis of NSCLC.

Lung cancer is the leading cause of cancer-related mortality all over the world. In recent years, pulmonary adenocarcinoma has surpassed squamous cell carcinoma in frequency and is the predominant form of lung cancer in many countries. Epidemiological investigations have shown an inverse relationship between garlic (Allium sativum) consumption and death rate from many cancers. Diallyl trisulfide (DATS) is one of the garlic-derived compounds (also known as: organosulfer compounds, OSC). DATS can induce apoptosis and inhibit the growth of many cancer cell lines. Our study demonstrated that the apoptotic incidents induced by DATS were a mitochondria-dependent caspase cascade through a significant decrease of the anti-apoptotic Bcl-2 that resulted in up-regulation of the ratio of Bax/Bcl-2 and the activity of caspase-3, -8, and -9. Eventually, DATS induced the apoptosis and inhibited the proliferation in a concentration- and time-dependent manner. Furthermore, by establishing an animal model of female BALB/c nude mice with A549 xenografts, we found that oral gavage of DATS significantly retarded growth of A549 xenografts in nude mice without causing weight loss or any other side effects compared with the control group. All the evidence both in vitro and in vivo suggested that DATS could be an ideal anti-cancer drug.

Reactive oxygen species (ROS) are at the center of many physiological and pathological processes. ROS generated due to oxidative stress can potentiate both cancer initiation and progression. Rotenone, which is an inhibitor of the mitochondrial electron transport chain complex I, results in the activation of NOX2 and release of ROS, and has been shown to display anticancer activity through the induction of apoptosis in various cancer cells. The mechanistic link between rotenone-dependent activation of NOX2 and induction of apoptosis is still elusive. In this study, we used the human lung cancer A549 cells to study the molecular mechanism(s) involved between rotenone-dependent activation of NOX2 and impairment of autophagic machinery. We report that acute exposure to rotenone induced mild NOX2-dependnet oxidative stress, which impaired the autophagic flux, resulting in cytosolic accumulation of LC3 and p62/STSQM1. We further show that this induction occurs through the PI3K/Akt/mTORC1 signaling pathway. We furthermore show that chronic exposure to rotenone lead to excessive NOX2-dependent ROS generation, increases autophagy, and decreases p62 level via increased-autophagic flux. Taken together, this study is the first mechanistic elucidation of how rotenone can be used to potently target cancer cells without overhauling the entire cellular machinery. © 2016 IUBMB Life 68(5):388-393, 2016.

Based on previous findings regarding the angiogenic activities and prognostic roles of metastasis-associated protein 1 (MTA1) in early-stage non-small cell lung cancer, the clinicopathological and prognostic significance of MTA1 protein expression, and its correlation with angiogenesis in lung invasive adenocarcinoma, were further assessed in the present study, according to the 2011 International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society classification. High protein expression levels of MTA1 were commonly observed in patients with lung invasive adenocarcinoma, and were significantly correlated with tumor size (P=0.030), lymph node metastasis (P=0.021) and microvessel density (P=0.015). Survival analysis demonstrated that patients with high protein expression levels of MTA1 exhibited significantly shorter five-year disease-free and overall survival than those patients whose protein expression levels of MTA1 were low (24.5% vs. 48.7%, P=0.001, and 34.7% vs. 59.2%, P=0.005, respectively). In addition, Cox regression multivariate analysis demonstrated that high protein expression levels of MTA1 significantly correlated with unfavorable five-year disease-free survival (P=0.024). These findings indicate that MTA1 protein expression may possess clinical potential as an indicator of progressive phenotype. Therefore, MTA1 is a promising prognostic predictor to identify subgroups of patients with high risk of relapse, and a potentially novel therapeutic target for antiangiogenesis in patients with lung invasive adenocarcinoma.

The nuclear receptor coactivator 5 (NCOA5) was a unique coactivator independent of AF2 that can modulate ERα-mediated transcription. Recent researches have indicated that its downregulation may participate in cancer development and progression. The aims of the present study were to investigate NCOA5 expression in esophageal squamous cell carcinoma (ESCC) and validate its possible influence on patients' prognosis. NCOA5 expression was examined by immunohistochemical staining in 119 ESCC patients' tissues. Ten paired tumor and adjacent normal specimens were examined by Western blot analysis. Statistical analysis was performed to assess its relevance with various clinicopathologic features and its influence on patients' survival. By immunohistochemistry analysis, NCOA5 expression was found to be significantly correlated with differentiation (P = 0.039), T status (P = 0.047) and stage (P = 0.036). Furthermore, we found NCOA5 higher expression in normal tissues than in tumor tissues by Western blot analysis. Univariate analysis showed that poor differentiation (P = 0.035, P = 0.027), lymph node metastasis (P < 0.001, P < 0.001), high T status (P = 0.010, P = 0.012), advanced stage (P < 0.001, P < 0.001) and NCOA5 low expression (P < 0.001, P < 0.001) were significantly correlated with poor prognosis of both disease-free survival (DFS) and overall survival (OS). Multivariate analysis showed that NCOA5 low expression (P = 0.019, P = 0.047), high T status (P = 0.015, P = 0.012), lymph node metastasis (P = 0.040, P = 0.021) and advanced stage (P = 0.017, P = 0.046) were independent prognostic factors of poor DFS and OS. Our findings suggest that NCOA5 low expression is associated with ESCC progression and is a potential biomarker in predicting poor prognosis. Further studies of NCOA5 may help develop new therapeutic strategies against ESCC.

Background The study was designed to detect the expression level of thimet oligopeptidase (THOP1) protein in non-small cell lung cancer (NSCLC) and investigate its correlation with clinicopathologic features and prognosis. Methods Immunohistochemical staining was used to determine the expression of THOP1 protein in 120 NSCLC specimens and 53 distant normal lung tissues. Quantitative real-time PCR and western blotting were employed to measure the expression of THOP1 in 16 pairs of primary NSCLC and corresponding normal tissues. Results Analysis of immunohistochemical staining suggested low THOP1 expression was found in 71 (59.2%) of the 120 NSCLC specimens and significantly correlated with positive lymph node metastasis (P = 0.048). However, low THOP1 expression was found in 22 (41.5%) of the 53 normal lung tissues. Chi-square test suggested that the expression of THOP1 was significantly higher in the normal lung tissues than that in the NSCLC specimens (P = 0.032). Real-Time PCR and western blotting showed that NSCLC specimens had decreased THOP1 mRNA and protein expression compared to corresponding normal tissues. Univariate analysis demonstrated that low THOP1 expression significantly predicted decreased 5-year disease-free survival (P = 0.038) and overall survival (P = 0.017). In addition, positive lymph node metastasis (P = 0.025) and advanced TNM stage (P = 0.009) significantly predicted decreased 5-year overall survival. However, multivariate Cox regression analysis showed that only low THOP1 expression retained its significance as an independent prognostic factor for unfavorable 5-year disease-free survival (P = 0.046) and overall survival (P = 0.021). Conclusions THOP1 may have clinical potentials to be employed as a promising biomarker to identify individuals with better prognosis and a novel antitumor agent for therapy of patients with NSCLC.

Background: Golgi phosphoprotein-3 (GOLPH3) is implicated in cancer development and progression. The aim of this study was to evaluate the prognostic significance of GOLPH3 protein and its association with tumor angiogenesis in patients with early-stage NSCLC. Materials and Methods: Immunohistochemistry was performed to determine GOLPH3 protein expression and allow assessment of intratumoral microvessel density (MVD) by counting CD-34 positive immunostained endothelial cells. Correlations of expression with MVD, clinicopathologic features and clinical prognosis were analyzed. Results: A notably higher level of GOLPH3 expression was found in early-stage NSCC tissues at the protein level. However, we do not find any correlation between GOLPH3 expression and clinicopathologic features (p>0.05), although higher MVD was positively associated with GOLPH3 overexpression (p

Lysosome-associated protein transmembrane-4 beta (LAPTM4B) is a novel oncogene, which has been indicated to be dramatically overexpressed in various malignant tumors. The aims of this study were to detect LAPTM4B protein expression in patients with non-small cell lung cancer (NSCLC) and then analyze the relationships of LAPTM4B protein with clinicopathologic factors, tumor angiogenesis and prognosis with SPSS statistical software. Immunohistochemistry was used to examine the expression of LAPTM4B and CD34 proteins in NSCLC tissues, and its results showed that LAPTM4B protein expression in NSCLC tissues was significantly higher than that in normal lung tissues (P < 0.001). Of the186 NSCLC cases, 129 (69.35 %) had strong expression of LAPTM4B protein, which was associated with histopathologic differentiation (P = 0.017), lymph node metastasis (P = 0.001) and TNM stage (P = 0.046), as well as the microvessel density (MVD) (P = 0.019). Kaplan-Meier survival analysis revealed that patients with strong LAPM4B protein expression and high MVD might have poor overall survival (OS; P = 0.001, P = 0.002, respectively) and disease-free survival (DFS; P = 0.002, P = 0.038, respectively). Multivariate analysis demonstrated that LAPTM4B protein was an independent prognostic marker for OS and DFS of NSCLC patients (P = 0.037, P = 0.046, respectively). These findings illustrated that LAPTM4B protein was closely associated with NSCLC progression, angiogenesis and poor prognosis, suggesting that LAPTM4B protein could be applied not only in predicting patient's outcome, but also in antiangiogenic therapy as a possible novel target molecule.

Background Sirtuin1 (SIRT1) is an NAD+-dependent type III histone deacetylase (HDAC). This research investigated the prevalence of SIRT1 protein expression and its prognostic influence with the aim of validating its potential role in lymphangiogenesis and lymphovascular invasion (LVI) in pN0 esophageal squamous cell carcinoma (ESCC). Methods A total of 206 patients were enrolled in this retrospective study. SIRT1 and VEGF-C protein expression was detected by immunohistochemical staining. Peritumoral lymphatic microvessel density (LVD) and LVI were evaluated by immunostaining for D2-40. Statistical analysis was then preformed to investigate the relevance of SIRT1 expression and various clinicopathologic features and to examine the effect of SIRT1 on tumor-induced lymphangiogenesis, LVI and prognosis. Results SIRT1 positive expression was identified in 95 cases in the nucleus and was significantly correlated with T status (P

In this study, we found that increased BRF2 protein expression was prevalent in NSCLC. Overexpression of BRF2 correlated with abnormal expression of E-cadherin, N-cadherin, and snail. Additionally, expression of BRF2 was found to be an independent prognostic factor in NSCLC patients. Furthermore, we showed that targeted knockdown of BRF2 expression could inhibit the migratory and invasive abilities of NSCLC cells and induced loss of the epithelial-mesenchymal transition of NSCLC cells. These results suggested that BRF2 overexpression in tumor tissues is significantly associated with the poor prognosis of NSCLC patients through promoting epithelial-mesenchymal transition (EMT) program.

BACKGROUND: The aim of this study was to examine BRF2 expression in patients with non-small cell lung cancer (NSCLC) and explore the relationship of BRF2 protein with clinicopathologic factors, tumor angiogenesis and prognosis. METHODS: Both BRF2 protein and intratumoral microvessels were examined by immunohistochemical staining in 107 non-small cell lung cancer patients. Intratumoral microvessel density (MVD) was measured by counting CD-34 positive immunostained endothelial cells. Western blot and RT-PCR analyses were utilized to investigate the BRF2 expression status in tissues. RESULTS: A notably higher level of BRF2 expression was found in NSCLC tissues at protein levels. In addition, univariate and multivariate analysis demonstrated that BRF2 protein over-expression and high MVD were significantly associated with tumor relapse. Although BRF2 overexpression and high MVD indicated poor 5-year overall survival (p = 0.004 and p = 0.019, respectively), multivariate analysis demonstrated that only BRF2 overexpression was an independent prognostic factor for unfavorable overall survival (P = 0.021). CONCLUSIONS: BRF2 is a promising biomarker to identify individuals with poor prognostic potential and a possible target for anti-angiogenic therapy for patients with early-stage NSCLC.

Background Pathological angiogenesis plays an essential role in tumor aggressiveness and leads to unfavorable prognosis. The aim of this study is to detect the potential role of Retinoblastoma binding protein 2 (RBP2) in the tumor angiogenesis of non-small cell lung cancer (NSCLC). Methods Immunohistochemical staining was used to detect the expression of RBP2, hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF) and CD34. Two pairs of siRNA sequences and pcDNA3-HA-RBP2 were used to down-regulate and up-regulate RBP2 expression in H1975 and SK-MES-1 cells. An endothelial cell tube formation assay, VEGF enzyme-linked immunosorbent assay, real-time PCR and western blotting were performed to detect the potential mechanisms mediated by RBP2 in tumor angiogenesis. Results Of the 102 stage I NSCLC specimens analyzed, high RBP2 protein expression is closely associated with tumor size (P = 0.030), high HIF-1α expression (P = 0.028), high VEGF expression (P = 0.048), increased tumor angiogenesis (P = 0.033) and poor prognosis (P = 0.037); high MVD was associated with high HIF-1α expression (P = 0.034), high VEGF expression (P = 0.001) and poor prognosis (P = 0.040). Multivariate analysis indicated that RBP2 had an independent influence on the survival of patients with stage I NSCLC (P = 0.044). By modulating the expression of RBP2, our findings suggested that RBP2 protein depletion decreased HUVECs tube formation by down-regulating VEGF in a conditioned medium. RBP2 stimulated the up-regulation of VEGF, which was dependent on HIF-1α, and activated the HIF-1α via phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. Moreover, VEGF increased the activation of Akt regulated by RBP2. Conclusions The RBP2 protein may stimulate HIF-1α expression via the activation of the PI3K/Akt signaling pathway under normoxia and then stimulate VEGF expression. These findings indicate that RBP2 may play a critical role in tumor angiogenesis and serve as an attractive therapeutic target against tumor aggressiveness for early-stage NSCLC patients.

Studies have shown that genetic activation of TFIIB-related factor 2 (BRF2) represents a unique mechanism of tumorigenesis through the increase in Pol III-mediated transcription. Several studies have shown that BRF2 is overexpressed in several types of cancer and suggest the oncogenic role of BRF2. This study aimed to examine the expression of TFIIB-related factor 2 (BRF2) in patients with esophageal squamous cell cancer (ESCC) and explore the relationship of BRF2 expression with clinicopathologic factors, tumor angiogenesis and prognosis. We found that increased BRF2 protein expression was prevalent in esophageal squamous cell cancer and was significantly associated with deeper tumor invasion (P = 0.039) and microvessel density (P = 0.007). Additionally, expression of BRF2 was found to be an independent prognostic factor in ESCC patients. Furthermore, a significant correlation between high BRF2 expression and shorter overall survival time was found in different subgroups of ESCC patients stratified by the clinical stage, T classification and lymph node metastasis. High expression of BRF2 protein is closely associated with tumor progression and angiogenesis and poor survival of ESCC. BRF2 is a promising biomarker to identify individuals with poor prognostic potential and concludes the possibility of its use as a prognostic marker in patients with ESCC.

Metastasis-associated protein 1 (MTA1) high expression has been detected in a wide variety of human aggressive tumors and plays important roles in the malignant biological behaviors such as invasion, metastasis, and angiogenesis. However, the specific roles and mechanisms of MTA1 protein in regulating the malignant behaviors of non-small-cell lung cancer (NSCLC) cells still remain unclear. To elucidate the detailed functions of MTA1 protein, we down-regulated the MTA1 protein expression in NSCLC cell line by RNA interference (RNAi) in vitro, and found that down-regulation of MTA1 protein significantly inhibited the migration and invasion potentials of 95D cells. Further research revealed that down-regulation of MTA1 protein significantly decreased the activity of matrix metalloproteinase-9, which could be the mechanism responsible for the inhibition of 95D cells migration and invasion. In addition, the tube formation assay demonstrated that the number of complete tubes induced by the conditioned medium of MTA1-siRNA 95D cells was significantly smaller than that of 95D cells. These findings demonstrate that MTA1 protein plays important roles in regulating the migration, invasion, and angiogenesis potentials of 95D cells, suggesting that MTA1 protein down-regulation by RNAi might be a novel therapeutic approach to inhibit the progression of NSCLC.