Resveratrol inhibits the proliferation, invasion, and migration, and induces the apoptosis of human gastric cancer cells through the MALAT1/miR-383-5p/DDIT4 signaling pathway.

Background: We aimed to study the effects and potential mechanism of resveratrol (RS) in gastric cancer (GC). Methods: The human GC cell line SGC7901 was treated with different concentrations of RS (0, 1, 5 µM) for 24 hours. The messenger ribonucleic acid or protein expressions levels of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), micro ribonucleic acid-383-5p (miR-383-5p), and DNA damage-inducible transcript 4 (DDIT4) in GC cells were determined by Western blot and quantitative real-time polymerase chain assays. Cells were then transfected with miR-383-5p inhibitor (inhibitor), inhibitor negative control (NC), MALAT1-interfering RNA (si-MALAT1), si-DDIT4 and negative interference control (si-NC). The Cell Counting Kit-8 method, scratch assay, and transwell assay were performed to evaluate cell proliferation, migration, and invasion. Additionally, flow cytometry was used to examine apoptosis, and the target relationship was examined by a luciferase-reporter gene analysis. Results: RS treatment downregulated the expression of MALAT1, repressed cell proliferation, inhibited cell migration and invasion (all P<0.05), and induced apoptosis (P<0.05) in GC cells. When the cells were treated with RS and inhibited the expression of MALAT1 meanwhile, the above anti-cancer effects were more significant (all P<0.05). Target prediction and the luciferase-reporter gene analysis showed that MALAT1 targeted miR-383-5p (P<0.05). When suppressing the expression of MALAT1 and miR-383-5p, the anti-cancer effects caused by the silencing of MALAT1 were absent (all P<0.05). We also found that miR-383-5p targeted DDIT4 protein. When the expression of miR-383-5p and DDIT4 in the GC cells was inhibited, the promoting cancer effects caused by the inhibition of miR-383-5p were reversed (all P<0.05). Conclusions: This study found that RS inhibited the proliferation, migration, and invasion of human GC cells through the metastasis-associated lung adenocarcinoma transcript 1 (MALAT1)/miR-383-5p/DDIT4 pathway and induced apoptosis.

Berbamine Suppresses the Growth of Gastric Cancer Cells by Inactivating the BRD4/c-MYC Signaling Pathway.

PURPOSE: Berbamine (Ber), a bioactive constituent extracted from a traditional Chinese medicinal herb, has been shown to exhibit broad inhibitory activity on a panel of cancer cell types. However, its effects and the underlying molecular mechanisms on gastric cancer (GC) remain poorly understood. METHODS: The anti-growth activity of Ber on two GC cell lines and normal gastric epithelial cell line were evaluated using MTS and clone formation assay. Flow cytometry analysis was employed to evaluate the cell cycle distribution and apoptosis of GC cells. Western blot and quantitative PCR (qPCR) analysis were employed to investigate the anti-GC mechanism of Ber. The inhibitory activity and binding affinity of Ber against BRD4 were evaluated by homogeneous time-resolved fluorescence (HTRF) and surface plasmon resonance (SPR) assay, respectively. Molecular docking and molecular simulations were conducted to predict the interaction mode between BRD4 and Ber. RESULTS: The results demonstrated that Ber reduced the proliferation of GC cell lines SGC-7901 and BGC-823 and induced cell cycle arrest and apoptosis. Mechanistically, Ber was identified as a novel natural-derived BRD4 inhibitor through multiple experimental assay, and its anti-GC activity was probably mediated by BRD4 inhibition. Molecular modeling studies suggested that Ber might bind to BRD4 primarily through hydrophobic interactions. CONCLUSION: Our study uncovered the underlying anti-GC activity of Ber in vitro and suggested that Ber holds promise as a potential lead compound in the discovery of novel BRD4 inhibitors.

CircHECTD1 up-regulates mucin 1 expression to accelerate hepatocellular carcinoma development by targeting microRNA-485-5p via a competing endogenous RNA mechanism.

BACKGROUND: Non-coding RNAs have attracted considerable attention for their vital role in cancer. The purpose of this study was to determine the effects of non-coding RNAs on hepatocellular carcinoma (HCC) and reveal their regulatory mechanism in the pathophysiological process. METHODS: We measured the expression of mucin 1 (MUC1) and miR-485-5p in tissues from 15 HCC patients and in liver cancer cell lines by quantitative real-time polymerase chain reaction and Western blot, screened for aberrantly expressed microRNAs (miRNAs) by miRNA microarrays. Bioinformatics tools were used to find the miRNA and circular RNA that regulated MUC1, which were validated by RNA immunoprecipitation assay and luciferase reporter assay. Cell counting kit-8, Transwell assays, and flow cytometry were used to conduct functional experiments. Proteins were examined by western blot and immunohistochemical staining assays. Significant differences between groups were estimated using the one-way analysis of variance. A P < 0.05 was considered statistically significant. RESULTS: MUC1 was overexpressed in HCC tissues compared with that in paratumor tissues (normal vs. tumor, 1.007 ±â€Š0.215 vs. 75.213 ±â€Š18.403, t = 18.401, P < 0.001) while miR-485-5p was down-regulated (normal vs. tumor, 4.894 ±â€Š0.684 vs. 1.586 ±â€Š0.398, t = 16.191, P < 0.001). Inhibition of miR-485-5p promoted cell proliferation (73.33% ±â€Š5.13% vs. 41.33% ±â€Š3.51%, t = 8.913, P < 0.001), migration (102 ±â€Š8 cells vs. 46 ±â€Š8 cells, t = 8.681, P < 0.001), invasion (59 ±â€Š7 cells vs. 28 ±â€Š2 cells, t = 8.034, P < 0.01), and suppressed apoptosis (22.64% ±â€Š6.97% vs. 36.33% ±â€Š3.96%, t = 2.958, P < 0.05) of HepG2 cells with which MUC1 is knocked down. Mechanically, miR-485-5p binds to MUC1, while circHECTD1 binds to miR-485-5p, resulting in the indirect up-regulation of the MUC1 level. CONCLUSIONS: Our findings reveal that circHECTD1 facilitates HCC progression by sponging miR-485-5p to up-regulate MUC1.

Phillygenin, a MELK Inhibitor, Inhibits Cell Survival and Epithelial-Mesenchymal Transition in Pancreatic Cancer Cells.

INTRODUCTION: Pancreatic cancer (PC) is one of the leading causes of cancer, with the lowest 5-year survival rate of all cancer types. Given the fast metastasis of PC and its resistance to surgery, radiotherapy, chemotherapy, and combinations thereof, it is imperative to develop more effective anti-PC drugs. Phillygenin (PHI) has been reported to exert anti-cancer, anti-bacterial, and anti-inflammatory properties. However, the mechanism of PHI in the development of PC is still unclear. METHODS: The cytotoxicity of PHI in pancreatic cancer cells was evaluated by MTT assay, and clonogenic assay was used to test the anti-proliferation of PHI. The pro-apoptotic effect of PHI was detected by flow cytometry analysis. The changes of epithelial-mesenchymal transition (EMT) in pancreatic cancer cells treated with PHI were determined by Western blot. Transwell assay was used to test the migration and invasion of PC cells after treatment with PHI. Molecular docking was used to predict the potential binding site of candidate target with PHI. RESULTS: PHI could inhibit the proliferation, migration, and EMT of PC cells (PANC-1 and SW1990) and induce its apoptosis. Analysis of the Cancer Genome Atlas database indicated that elevated MELK levels correlated with poor overall survival (OS) and disease-free survival (DFS) of PC patients. In addition, molecular modeling showed that PHI may potentially target the catalytic domain of maternal embryonic leucine zipper kinase (MELK). Overexpression of MELK muted the anti-PC effects of PHI. CONCLUSION: PHI holds promise as a potent candidate drug for the treatment of PC via targeted MELK.

Resveratrol suppresses the invasion and migration of human gastric cancer cells via inhibition of MALAT1-mediated epithelial-to-mesenchymal transition.

Resveratrol, a natural polyphenolic phytoalexin, was reported to exert multiple anticancer effects as a traditional Chinese medicine. However, research regarding the anticancer mechanism of resveratrol for the treatment and prevention of gastric cancer has reported conflicting results. In the present study, it was determined that resveratrol inhibited cell viability in a dose-dependent manner in the human gastric cancer cell line BGC823. Cell migration and invasion were suppressed significantly following treatment with 200 µM resveratrol. Additionally, resveratrol inhibited metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) expression, which was overexpressed in gastric cancer cells. Further experiments revealed that MALAT1 knockdown suppressed cell viability, migration, invasion and epithelial-to-mesenchymal transition in BGC823 cells. The present study indicated that resveratrol inhibited migration and invasion in human gastric cancer cells via suppressing MALAT1-mediated epithelial-to-mesenchymal transition, providing novel evidence for understanding the anticancer mechanism of resveratrol.

Correlations of PD-L1 gene polymorphisms with susceptibility and prognosis in hepatocellular carcinoma in a Chinese Han population.

AIMS: This study was performed to investigate the effect of PD-L1 polymorphisms on the susceptibility and prognosis of hepatocellular carcinoma (HCC) in a Chinese Han population. METHODS: Four single nucleotide polymorphisms (SNPs) of the PD-L1 gene, including rs2297136 (C > T), rs4143815 (C > G), rs2890658 (A > C) and rs17718883 (C > G) were examined in 225 HCC patients and 200 healthy controls using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method. RESULTS: Data revealed that the rs2297136 (C > T) SNP TT (p = 0.03) and rs4143815 (C > G) SNP GG genotypes (p < 0.001) were associated with significantly increased risks of HCC. No association was found between rs2890658 (A > C) SNP and HCC risk and this risk was significantly decreased in individuals with the rs17718883 SNP CG + GG genotype (p < 0.001). The rs2297136 (C > T) SNP CC + CT genotypes, the rs4143815 (C > G) CC genotype and the rs2890658 (A > C) AA genotype were associated with increased overall survival compared to their counterpart allelic genotypes (p < 0.001). The rs2890658 (A > C) SNP had no impact on the risk and prognosis of HCC (p > 0.05). CONCLUSIONS: Our results indicated that three functional polymorphisms (rs2297136, rs4143815 and rs17718883) of the PD-L1 gene were associated with HCC risk and prognosis, suggesting that genetic variants of PD-L1 polymorphisms might be a possible prognostic marker for the prediction of HCC risk and development. Validation by a larger prospective study from a more diverse ethnic population is needed to confirm these findings.