Update on the association of miR-149 rs2292832 C>T polymorphism with gastric cancer risk: A meta-analysis study of gastrointestinal cancers.

OBJECTIVE: Single nucleotide polymorphisms in microRNAs are believed to affect the occurrence and progression of cancer by altering the expression and biological functions of microRNAs. Several studies investigated the role of the miR-149 rs2292832 C>T polymorphism on the risk of gastric cancer (GC), but got conflicting results. METHODS: We performed a comprehensive and systematic search through the PubMed MEDLINE, Google Scholar, Science Direct, Scopus, CNKI, and Web of science, 8 studies were included in the meta-analysis to determine whether miR-149 rs2292832 C>T polymorphism contributed to the risk of GC. RESULTS: Pooled data indicated that miR-149 rs2292832 C>T polymorphism was not associated with GC risk. In the stratified analysis by ethnicity, miR-149 rs2292832 C>T polymorphism significantly increased GC risk under the allele comparison model (odds ratio [OR] = 1.27, 95% CI = 1.04-1.55, Pheterogeneity = 0.18, P = .02), recessive model (OR = 1.44, 95% CI = 1.04-2.01, Pheterogeneity = 0.19, P = .03) among Caucasians; but decreased GC risk under the allele comparison model (OR = 0.89, 95% CI = 0.81-0.98, Pheterogeneity = 0.22, P = .02) and dominant model (OR = 0.82, 95% CI = 0.72-0.93, Pheterogeneity = 0.15, P = .01) among Asian. CONCLUSION: Our meta-analysis suggests a positive correlation between miR-149 rs2292832 C>T polymorphism and GC development among Caucasians, but negative correlation among Asian population.

MTRR rs1532268 polymorphism and gastric cancer risk: evidence from a meta-analysis.

OBJECTIVE: The methionine synthase reductase (MTRR) gene encodes the MTRR enzyme involved in the metabolic pathway of homocysteine. Several studies investigated the effect of the MTRR rs1532268 gene polymorphism on the risk of gastric cancer (GC), but the results have been inconsistent. METHODS: We performed a comprehensive and systematic search of PubMed, Google Scholar, MEDLINE, Science Direct, Scopus, CNKI, and Web of Science. Five studies were included in this meta-analysis to determine whether MTRR rs1532268 polymorphism contributes to the risk of GC. RESULTS: Pooled data indicated that the MTRR rs1532268 polymorphism significantly increased GC risk under the allele comparison model (odds ratio [OR] = 1.14, 95% confidence interval [CI] = 1.01-1.29) and dominant model (OR = 1.14, 95% CI = 1.00-1.30). In the analysis stratified by ethnicity, no relationship was found in Whites or Asians. CONCLUSION: Our meta-analysis suggests a positive correlation between MTRR rs1532268 polymorphism and GC development.

The Effect of Compound Sophora on Fluorouracil and Oxaliplatin Resistance in Colorectal Cancer Cells.

Fluorouracil (5-FU) and oxaliplatin (L-OHP) are the most commonly used chemotherapy drugs for colorectal cancer, though resistance is common. Compound Sophora injection is a traditional Chinese medicine that can protect the liver against oxidation, improve immunity, and enhance sensitivity to chemotherapy; it may have an effect of reversing resistance in 5-FU- and L-OHP-resistant gastric cancer cells (5-FU/SW480 and L-OHP/SW480, respectively). A concentration gradient experiment was performed to identify a nontoxic dose of compound Sophora injection. 5-FU/SW480 and L-OHP/SW480 cells were treated with the nontoxic dose of compound radix Sophorae injection for 48 h, and changes in drug resistance to 5-FU and L-OHP were detected. Alterations in apoptosis and the cell cycle were assessed, as were the mRNA and protein levels of permeability glycoprotein (P-gp), annexin A1 (ANXA1), and ATP-binding cassette superfamily G member 2 (ABCG2). Flow cytometry showed a reduction in the number of cells in the G1 phase and an increase of cells in the S phase (P < 0.05). mRNA and protein expression of P-gp and ABCG2 was significantly higher in 5-FU/SW480 and L-OHP/SW480 cell lines, and ANXA1 expression decreased significantly (P < 0.05). Compound Sophora injection can reverse the drug resistance of 5-FU/SW480 and L-OHP/SW480 cell lines to 5-FU and L-OHP, respectively, possibly through a mechanism involving reduced expression of P-gp and ABCG2 but enhanced expression of ANXA1, which is the basis for the identification of clinical drug resistance in colorectal cancer.