RESUMEN
Lung cancer is a crucial global issue, with more than one million deaths annually. While smoking is considered the main etiology of the disease, several genetic variants are associated with it. Alterations in vitamin D pathway genes have also been studied in regards to lung cancer, but the findings have been inconclusive. We here present a systematic review and meta-analysis of seven genes in this pathway: CYP2R1, CYP27B1, CYP24A1, CYP3A4, CYP3A5, GC, and VDR. Four databases (PubMed, Scopus, Cochrane Library, and Web of Science (WOS) databases) were searched. From these, 16 eligible case-control studies comprising 6,206 lung cancer cases and 7,272 health controls were obtained. These studies were subjected to comprehensive data extraction and quality scoring, and the pooled odds ratio with a 95% confidence interval was calculated to estimate the effect of each variant along with heterogeneity analysis and a risk of bias assessment. Our meta-analysis revealed an association between CYP3A4 (rs2740574) and lung cancer in the allelic, heterozygous, and dominant models. In addition, both VDR (Fok1: rs2228570) and VDR (Cdx-2: rs11568820) displayed a protective role in lung cancer development in the heterozygous and dominant models. Furthermore, VDR (Taq1: rs731236) showed a decreased risk of lung cancer in the allelic, homozygous, and recessive models. Similarly, VDR (BsmI: rs1544410) had a positive effect on lung cancer risk when subjected to allelic and recessive models. Our meta-analysis revealed the lack of association of CYP2R1 (rs10741657), CYP27B1 (rs3782130), CYP27B1 (rs10877012), CYP24A1 (rs6068816), CYP24A1 (rs4809960), CYP3A5 (rs776746), GC (rs7041), GC (rs4588), and VDR (ApaI: rs7975232) with lung cancer. Our work revealed that CYP3A4 (rs2740574) can represent an independent risk factor for lung cancer. This conclusion can aid better personalized medicine for lung cancer management, while further assessment for genetic variants of CYP3A4, CYP27B1, CYP24A1, GC, and VDR is still required to address more robust evidence.
RESUMEN
AIMS: MicroRNAs (miRNAs) are non-coding RNAs that control post-transcriptional gene expression. Recently, miRNAs were confirmed to be promising biomarkers for different pathological conditions. This study assessed the role of serum miR-16 and miR-375 in HCC development in chronic liver disease patients such as cirrhosis. Moreover, miR-16 and miR-375 levels were estimated in HCC cell lines (HepG2 and Huh7) after treatment with doxorubicin (DOX), thymoquinone (TQ) and their combination. MAIN METHODS: Serum miR-16 and miR-375 were analyzed in 30 HCC patients, 20 cirrhosis patients and 10 healthy volunteers using RT-PCR. Moreover, HepG2 and Huh7 cells were incubated with DOX, TQ or TQ/DOX combination for 24 h and the levels of miR-16, miR-375 and gene expression of anti-apoptotic protein BCL-2 were determined in cell lysates using RT- PCR. Moreover, the ability of DOX, TQ and TQ/DOX combination to induce apoptosis were analyzed by measuring caspase-3 expression using ELISA method. KEY FINDINGS: Serum miR-16 and miR-375 levels were significantly decreased in HCC patients as compared to cirrhosis and healthy control group. Also, combined use of serum miR-16 and miR-375 showed a better predictive ability than each alone. Moreover, the expression level of miR-16 and miR-375 in HepG2 and Huh7 cells increased significantly after treatment with DOX and TQ. Also, TQ/DOX combination improved apoptosis by increasing caspase-3 expression and decreasing of BCL-2 expression. SIGNIFICANCE: This study proved that the combined use of serum miR-16 and miR-375 was better than each alone for HCC detection. Moreover, TQ induced apoptosis and upregulatedmiR-16 and miR-375 expression in HCC cells that may explain its anticancer activity.