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BackgroundN-myc (and STAT) interactor (NMI) plays vital roles in tumor growth, progression, and metastasis. In this study, we identified NMI as a potential tumor suppressor in lung cancer and explored its molecular mechanism involved in lung cancer progression.MethodsHuman lung cancer cell lines and a mouse xenograft model was used to study the effect of NMI on tumor growth. The expression of NMI, COX-2 and relevant signaling proteins were examined by Western blot. Tissue microarray immunohistochemical analysis was performed to assess the correlation between NMI and COX-2 expression in lung cancer patients.ResultsNMI was highly expressed in normal lung cells and tissues, but lowly expressed in lung cancer cells and tissues. Overexpression of NMI induced apoptosis, suppressed lung cancer cell growth and migration, which were mediated by up-regulation of the cleaved caspase-3/9 and down-regulation of phosphorylated PI3K/AKT, MMP2/MMP9, β-cadherin, and COX-2/PGE2. In contrast, knockdown of NMI promoted lung cancer cell colony formation and migration, which were correlated with the increased expression of phosphorylated PI3K/AKT, MMP2/MMP9, β-cadherin and COX-2/PGE2. Further study showed that NMI suppressed COX-2 expression through inhibition of the p50/p65 NF-κB acetylation mediated by p300. The xenograft lung cancer mouse models also confirmed the NMI-mediated suppression of tumor growth by inhibiting COX-2 signaling. Moreover, tissue microarray immunohistochemical analysis of lung adenocarcinomas also demonstrated a negative correlation between NMI and COX-2 expression. Kaplan-Meier analysis indicated that the patients with high level of NMI had a significantly better prognosis.ConclusionsOur study showed that NMI suppressed tumor growth by inhibiting PI3K/AKT, MMP2/MMP9, COX-2/PGE2 signaling pathways and p300-mediated NF-κB acetylation, and predicted a favorable prognosis in human lung adenocarcinomas, suggesting that NMI was a potential tumor suppressor in lung cancer.

Melanoma is an aggressive cutaneous malignancy, illuminating the exact mechanisms and finding novel therapeutic targets are urgently needed. In this study, we identified KMT2A as a potential target, which promoted the growth of human melanoma cells. KMT2A knockdown significantly inhibited cell viability and cell migration and induced apoptosis, whereas KMT2A overexpression effectively promoted cell proliferation in various melanoma cell lines. Further study showed that KMT2A regulated melanoma cell growth by targeting the hTERT-dependent signal pathway. Knockdown of KMT2A markedly inhibited the promoter activity and expression of hTERT, and hTERT overexpression rescued the viability inhibition caused by KMT2A knockdown. Moreover, KMT2A knockdown suppressed tumorsphere formation and the expression of cancer stem cell markers, which was also reversed by hTERT overexpression. In addition, the results from a xenograft mouse model confirmed that KMT2A promoted melanoma growth via hTERT signaling. Finally, analyses of clinical samples demonstrated that the expression of KMT2A and hTERT were positively correlated in melanoma tumor tissues, and KMT2A high expression predicted poor prognosis in melanoma patients. Collectively, our results indicate that KMT2A promotes melanoma growth by activating the hTERT signaling, suggesting that the KMT2A/hTERT signaling pathway may be a potential therapeutic target for melanoma.

Background: Colorectal cancer (CRC) is one of the most common malignancies, and early detection plays a crucial role in enhancing curative outcomes. While colonoscopy is considered the gold standard for CRC diagnosis, noninvasive screening methods of DNA methylation biomarkers can improve the early detection of CRC and precancerous lesions. Methods: Bioinformatics and machine learning methods were used to evaluate CRC‐related genes within the TCGA database. By identifying the overlapped genes, potential biomarkers were selected for further validation. Methylation‐specific PCR (MSP) was utilized to identify the associated genes as biomarkers. Subsequently, a real‐time PCR assay for detecting the presence of neoplasia or cancer of the colon or rectum was established. This screening approach involved the recruitment of 978 participants from five cohorts. Results: The genes with the highest specificity and sensitivity were Septin9, AXL4, and SDC2. A total of 940 participants were involved in the establishment of the final PCR system and the subsequent performance evaluation test. A multiplex TaqMan real‐time PCR system has been illustrated to greatly enhance the ability to detect precancerous lesions and achieved an accuracy of 87.8% (95% CI 82.9–91.5), a sensitivity of 82.7% (95% CI 71.8–90.1), and a specificity of 90.1% (95% CI 84.3–93.9). Moreover, the detection rate of precancerous lesions of this assay reached 55.0% (95% CI 38.7–70.4). Conclusion: The combined detection of the methylation status of SEPT9, SDC2, and ALX4 in plasma holds the potential to further enhance the sensitivity of CRC detection. [ABSTRACT FROM AUTHOR]

Nav1.5, encoded by SCN5A, has been associated with metastasis in colorectal cancer (CRC). Here, we investigated the mechanism by which Nav1.5 regulates tumor progression and whether Nav1.5 influences chemosensitivity to 5-fluorouracil (5-FU) in CRCs. CRC cases were evaluated for Nav1.5 expression. Elevated Nav1.5 expression was associated with poor prognosis in CRCs, whereas stage II/III patients with upregulated SCN5A expression could have better survival after receiving 5-FU-based adjuvant chemotherapy. In CRC cells, SCN5A knockdown reduced the proliferation, migration and invasion. According to RNA sequencing, SCN5A knockdown inhibited both the cell cycle and epithelial-mesenchymal transition. In addition, Nav1.5 stabilized the KRas-calmodulin complex to modulate Ras signaling, promoting Ca2+ influx through the Na+-Ca2+ exchanger and Ca2+ release-activated calcium channel. Meanwhile, SCN5A knockdown increased the 50% inhibitory concentration to 5-FU by upregulating 5-FU-stimulated apoptosis in CRCs. In conclusion, Nav1.5 could progress to proliferation and metastasis through Ca2+/calmodulin-dependent Ras signaling in CRC, and it could also enhance 5-FU-stimulated apoptosis. Clinically, patients with stage II/III CRCs with elevated SCN5A expression demonstrated poor prognosis, yet those patients could benefit more from 5-FU-based chemotherapy than patients with lower SCN5A expression. [ABSTRACT FROM AUTHOR]

Introduction: Regulator of chromatin condensation 1 (RCC1) is a major guanine-nucleotide exchange factor for Ran GTPase, and it plays key roles in various biological processes. Previous studies have found that RCC1 may play a role in the development of tumors, but little is known about the relationship between RCC1 and colorectal liver oligometastases (CLOs). Methods: One hundred and twenty-nine pairs of matched human CLO samples, including both primary tumor and its liver metastasis specimens, were subjected to immunohistochemistry to determine the location and expression levels of RCC1. Associations between RCC1 and survival as well as gene expression profiling were explored. Results: In this study, we first observed that RCC1 was mildly increased in CLO tumor tissues compared with normal tissues, and the localization was primarily nuclear. In addition, our study found that high RCC1 expression in liver oligometastases was an independent prognostic marker for unfavorable recurrence-free survival and overall survival ( p = 0.036 and p = 0.016). Gene expression profiles generated from microarray analysis showed that RCC1 was involved in pathways including "Myc targets," "E2F targets" and "DNA repair" pathways. Conclusion: Our data indicated that RCC1 was expressed mainly in the nucleus, and strong and significant associations were found between RCC1 expression levels and the survival of CLO patients. These findings indicated that RCC1 may play a role in CLO development., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Deng, Yu, Zhao, Peng, Xu, Qin, Xiao, Liu, Li, Fang and Pan.)

Na v 1.5, encoded by SCN5A, has been associated with metastasis in colorectal cancer (CRC). Here, we investigated the mechanism by which Na v 1.5 regulates tumor progression and whether Na v 1.5 influences chemosensitivity to 5-fluorouracil (5-FU) in CRCs. CRC cases were evaluated for Na v 1.5 expression. Elevated Na v 1.5 expression was associated with poor prognosis in CRCs, whereas stage II/III patients with upregulated SCN5A expression could have better survival after receiving 5-FU-based adjuvant chemotherapy. In CRC cells, SCN5A knockdown reduced the proliferation, migration and invasion. According to RNA sequencing, SCN5A knockdown inhibited both the cell cycle and epithelial-mesenchymal transition. In addition, Na v 1.5 stabilized the KRas-calmodulin complex to modulate Ras signaling, promoting Ca 2+ influx through the Na + -Ca 2+ exchanger and Ca 2+ release-activated calcium channel. Meanwhile, SCN5A knockdown increased the 50% inhibitory concentration to 5-FU by upregulating 5-FU-stimulated apoptosis in CRCs. In conclusion, Na v 1.5 could progress to proliferation and metastasis through Ca 2+ /calmodulin-dependent Ras signaling in CRC, and it could also enhance 5-FU-stimulated apoptosis. Clinically, patients with stage II/III CRCs with elevated SCN5A expression demonstrated poor prognosis, yet those patients could benefit more from 5-FU-based chemotherapy than patients with lower SCN5A expression., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Objective: To explore clinicopathologic characteristics, surgical features and prognostic factors in patients with primary gastrointestinal lymphoma(PGIL) in order to provide evidence for optimizing surgical treatment., Methods: Clinicopathological data of 57 PGIL patients undergoing abdominal surgery in Sun Yat-sen University Cancer Center between October 1990 and January 2015 were retrospectively collected. The survival rates were compared among patients with different clinicopathologic characteristics by Kaplan-Meier method, while Cox regression model was employed to analyze the prognostic factors., Results: Among 57 patients, 43 were male and 14 were female, with a median age of 48 (range 16 to 80) years. Seventeen (29.8%) cases were classified as Musshoff I( stage, 19 (33.3%) cases as II( stage, 9 (15.8%) cases as III( stage, and 12(21.1%) cases as IIII( stage. Forty-four (77.2%) cases underwent selective operation, 13(22.8%) cases underwent emergent operation due to acute abdomen. Thirty-two(56.1%) cases had radical resection, 18 (31.6%) cases had partial resection and the rest 7(12.3%) cases failed to perform resection. Four (7.0%) cases received simple surgical operation, and 53 (93.0%) cases received comprehensive treatment, including 5(8.8%) cases with preoperative chemotherapy and surgery, 40 (70.2%) cases with surgery and postoperative chemotherapy, and 8 (14.0%) cases with surgery and perioperative chemotherapy. Stage III( and IIII( accounted for 76.9%(10/13) in patients undergoing emergent operation and accounted for 25.0%(11/44) in patients undergoing selective operation, whose difference was statistically significant (χ 2 =9.503, P=0.002). Univariate prognostic analysis showed that T lymphocyte source pathological cell phenotype (P=0.000), clinical Musshoff stage III( and IIII((P=0.001), emergent operation (P=0.000) and incomplete tumor resection(P=0.007) had worse 5-year overall survival. Multivariate Cox regression analysis indicated that tumor pathological cell phenotype (HR=13.75, 95%CI:3.546-53.308, P=0.000) and surgical timing (HR=7.497, 95%CI:1.163-48.313, P=0.034) were independent prognostic risk factors of patients with stage I( and II(., Conclusions: Surgical operation is an important part of comprehensive treatment for PGIL. T lymphocyte source and ulcerative lymphoma indicates poorer prognosis.