ABSTRACT
OBJECTIVE: Treatment of the high-risk triple negative breast cancer (TNBC) is a critical clinical challenge. Here we aimed to explore a novel strategy for TNBC treatment by blocking the tumor-associated chemokine CXCL13 in the MDA-MB-231 TNBC cells. MATERIALS AND METHODS: MDA-MB-231 cells were treated with anti-CXCL13 antibodies (inhibition group), or phosphate-buffered saline (PBS) (control group), followed by determining the levels of interleukin-1 (IL-1), tumor necrosis factor-alpha (TNF-α) and transforming growth factor beta-1 (TGF-ß1) with enzyme-linked immunosorbent assay (ELISA). The effects of CXCL13 inhibition on cell proliferation and apoptosis were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay and flow cytometry, respectively. Quantitative Real Time-PCR (qRT-PCR) and Western blot were used to compare the levels of CXCL13, CXCR5, extracellular signal-regulated kinase (ERK). The levels of cyclin D1 and cleaved caspase-9 were detected by Western blot. RESULTS: The levels of IL-1, TNF-α and TGF-ß1 in MDA-MB-231 cells treated with anti-CXCL13 antibodies were significantly downregulated (p<0.05). Meanwhile, CXCL13 blockade decreased the cell proliferation and increased the apoptosis rate of MDA-MB-231 cells. The inhibition of CXCL13 led to marked reduction in CXCL13 and CXCR5 mRNA and an increase in ERK mRNA. The inhibition of CXCL13 resulted in the downregulation of CXCL13, CXCR5, p-ERK/ERK, cyclin D1 and upregulation of cleaved caspase-9 proteins. CONCLUSIONS: CXCL13 blockade effectively suppressed the proliferation of MDA-MB-231 cells by promoting cell apoptosis. This effect is presumably associated with the downregulation of CXCL13 and suppression of the CXCR5/ERK signaling pathway.
Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Chemokine CXCL13/antagonists & inhibitors , Signal Transduction/drug effects , Triple Negative Breast Neoplasms/drug therapy , Antineoplastic Agents/therapeutic use , Cell Line, Tumor , Chemokine CXCL13/metabolism , Drug Screening Assays, Antitumor , Extracellular Signal-Regulated MAP Kinases/metabolism , Female , Humans , Receptors, CXCR5/metabolism , Triple Negative Breast Neoplasms/pathologyABSTRACT
The aim of the present study was to investigate the clinical significance of microRNA-218 (miR-218) in gastric cancer. We enrolled 112 patients having undergone surgery for gastric cancer between May 2008 and June 2014. Expression of miR-218 was determined by real-time quantitative reverse transcription-polymerase chain reaction. Survival curves were plotted using the Kaplan-Meier method and compared by the log-rank test. We found that miR-218 expression was significantly downregulated in gastric cancer tissues compared to adjacent normal tissues (P < 0.001). Low miR-218 expression was significantly associated with tumor differentiation (P < 0.001), depth of tumor invasion (P = 0.006), and tumor node metastasis stage (P < 0.001). Kaplan-Meier survival analysis revealed that patients with low miR-218 levels showed significantly lower 5-year overall survival than those demonstrating high expression (P = 0.04). Multivariate Cox regression analyses indicated that low miR-218 expression constitutes an independent molecular biomarker for prediction of poor overall survival of gastric cancer patients (hazard ratio = 3.187, 95% confidence interval = 1.551-8.365, P = 0.037). In conclusion, miR-218 was remarkably downregulated in gastric cancer tissues and may serve as a prognostic biomarker for patients suffering from this disease.
