Mutational and expressional association of the PIK3CA gene with the risk of breast cancer in the Pakistani population.

PI3K pathway is a very important pathway that is reported to be involved in breast cancer. Mutation of PI3K and p110 alpha-catalytic subunit of phosphatidylinositol 3-kinase (PIK3CA) is of high predictive and prognostic values in breast cancer. The purpose of the current study was to screen the hotspot mutations of the PIK3CA gene i.e. rs2677760, rs3806685, rs121913273 & rs121913279 along with expressional analysis of PI3K and PIK3CA genes in breast cancer female patients. For mutational analysis, TaqMan assay & Sanger sequencing were performed while for expressional analysis real-time PCR was carried out. Mutant allele C of rs2677760 was observed to be high in postmenopausal patients. The frequency of mutant allele G of rs3806685 was significantly high in breast cancer patients. All diseased and control samples were of wild type for the hotspot rs121913273 and rs121913279 with allele G for rs121913273 and A for rs121913279. Expression of the PI3K was high in breast cancer tissue samples as compared to the adjacent controls. While the expression of the thePIK3CA gene was significantly high in premenopausal breast cancer patients. It was concluded that the mutant allele C of rs2677760 might have some sort of association with the menopausal status and it could be used as a diagnostic marker in post-menopausal women if studied further. Mutant allele G of rs3806685 was also found to be associated with breast cancer. While multiallelic rs121913273 and rs121913279 showed a different trend for the studied population. For expressional analysis, PI3K showed over-expression in the cases while PIK3CA gene expression was observed to be significantly associated with pre-menopausal status.

Analysis of Rare Alleles of miRNA-146a (rs2910164) and miRNA-34b/c (rs4938723) as a Prognostic Marker in Thyroid Cancer in Pakistani Population.

Background: Rationale: The miRNAs are short non-coding functional RNAs that are involved in the regulation of transcriptomes. It was found that human miRNA-146a and miRNA34b/c are important microRNAs and are functioning either as onco-miRNAs, or acting as tumor suppressors, in different conditions. To date, no study has been performed to evaluate the alterations of miRNA-146ars2910164 and miRNA34b/crs4938723 polymorphism as a risk factor in the development of thyroid cancer in the Pakistani population. Mutational analysis of rs2910164 and rs4938723 of miRNA-146a and miRNA-34b/c was carried out to check their association with the development of thyroid carcinogenesis. Material and Methods: Papillary thyroid cancer (PTC) patients with age and gender-matched controls were recruited for the present study. DNA extraction, genotyping of rs2910164 and rs4938723 was carried out by ARMS-PCR. Statistical analyses were carried out using SPSS software (version 20). Results: The odds ratio for risk allele C of rs2910164 for patients and controls was 23.0168 (3.0321−174.7208) with a p-value of <0.0001, showing that the frequency of the major allele G was lower in patients while the frequency of minor allele C was higher in patients. Similarly, the odds ratio for risk allele C of rs4938723 was 1.8621 (1.0321−3.3596) with a p-value of <0.03788 showing significant association with the development of thyroid cancer. Conclusions: The study highlights the significant association of miRNAs SNPs as one of the genetic risk factor for PTC. It was concluded that miRNA-146a (rs2910164) showed higher frequency of minor allele C in patients. Similarly in miRNA-34b/c gene SNP rs4938723 was observed to have a strong association with the development of thyroid cancer as the frequency of rare allele C was higher in patients.

Potential risk assessment of miR-143 gene polymorphisms rs41291957 and rs353292 in colorectal cancer.

Colorectal cancer is a life-threatening and therapeutically challenging disease. Increasingly it is being deciphered that genetic and epigenetic mutations play a central role in cancer onset and progression. Excitingly, discovery of non-coding RNAs is considered to be a milestone in molecular oncology and emerging evidence is deepening our understanding about pivotal role of miRNAs in carcinogenesis. miR-143 has been experimentally verified to play an instrumental role as tumor suppressor. Recent studies suggest that single nucleotide polymorphisms rs41291957 and rs353292 in miR-143 may associate with the progression and or development of colorectal cancer. In present study 400 Pakistani subjects participated including 200 colorectal cancer patients and 200 age and gender matched healthy individuals. Blood samples and clinical information of the confirmed patients was collected from cancer diagnosis and treatment hospitals in Pakistan. The polymorphisms rs41291957 and rs353292 were genotyped in patients and controls by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) and results were validated by Sanger sequencing. The association of the SNPs within the study group was analyzed by χ² test with p value < 0.05 as significant. Odds ratio was calculated with 95% confidence interval.Genetic predisposition to cancer was observed in presence of characteristic rs45291957 polymorphism. χ² test results show strongly significant association mi-RNA rs45291957 SNP with colorectal cancer p value 0.0111 (<0.05) along with the statistically significant correlation tested by odds ratio with 95% confidence interval. However, no significant correlation (p value 0.6683) could be found for the association of rs353292 with colorectal cancer in Pakistani population. The present study for the first time gave evidence of miR-143 rs41291957 involvement in colorectal cancer patients of Pakistani population. This target can be a useful molecular tool for the prognosis and treatment targets for colorectal cancer in Pakistani population. rs353292 genetic association can be explored for different cancers in Pakistan to completely rule out its role in cancer.