Individuals with homozygous variant genotypes for GSTP1 or COMT exhibited a higher risk of developing breast cancer than those with wild-type genotypes; however, for CYP1B1, the homozygous variant genotype was associated with a lower risk, and the heterozygous genotype for these 3 genes was not associated with breast cancer development.An individual's risk of breast cancer is only influenced by the specific combination of risk-associated alleles of COMT and GSTP1, despite the protective effects of the homozygous CYP1B1 genotype revealed by univariate analysis.
Four hypermethylated alleles (RARβ2, BRCA1, GSTP1 and RASSF1A) related to breast cancer in twenty-three clinical samples were tested using the microwell chip dPCR-based MethyLight assay.
Our study is the first of its kind in Kashmiri population, which indicates that GSTP1 shows aberrant methylation pattern in the breast cancer with the consequent loss in the protein expression.
Previous studies have identified GSTP1 as a predictor of prognosis and chemo-resistance in breast cancer patients, but the mechanisms governing GSTP1-dependent drug resistance are still unclear.
We investigated whether GSTT1 ("null" allele), GSTM1 ("null"allele), GSTP1 (A313G), RFC1 (G80A), MTHFR (C677T), TS (2R/3R) polymorphisms were associated with toxicity and survival in patients with early breast cancer (EBC) treated with adjuvant chemotherapy (CT).
However, quantitation of methylation confirmed a hypermethylated phenotype at CDH1 and GSTP1 promoters as well as a differential methylation pattern at DNMT3B promoter in breast cancer.
Increasing adherence to the MD reduced BC risk in women with at least one GSTP1 Ile allele (OR for Ile/Ile = 0.84, 95 % CI 0.74-0.95, for Ile/Val = 0.73, 95 % CI 0.62-0.85) or one NAT2 590G allele (OR for 590 GG = 0.73, 95 % CI 0.63-0.83, for 590 GA = 0.81, 95 % CI 0.70-0.94). p interaction values were not, however, statistically significant.
And the heterogeneity present in different studies, evaluating the association of GSTP1 polymorphism with response to anthracycline-based chemotherapy, disappeared in breast cancer patients after subgroup analysis by chemotherapy regimen was performed.
The meta-analysis indicated that the GSTP1rs1695 A>G polymorphism did not contribute to the susceptibility of BC when the overall population was considered.
Our data demonstrate that these ESR1, GSTP1, and CYP19 polymorphisms are associated with risk of BC, and the risk haplotype TGGGGTC could help to identify populations with high susceptibility to BC in Chinese women.
This study retrospectively explored pharmacogenetic associations of single nucleotide polymorphisms (SNPs) of the uridine glucuronosyltransferase 2B7 (UGT2B7, rs7668258), glutathione-S-transferase pi 1 (GSTP1, rs1695), and microcephalin 1 (MCPH1, rs2916733) genes with chemotherapy-related adverse events in 102 Japanese women who received epirubicin and cyclophosphamide as perioperative chemotherapy for early breast cancer.
Methylation-sensitive high-resolution melting was used to screen promoter methylation in a panel of 13 genes reported as methylated in breast cancer (RASSF1A, TWIST1, APC, WIF1, MGMT, MAL, CDH13, RARβ, BRCA1, CDH1, CDKN2A, TP73, and GSTP1) in 29 tumour pairs (16 ipsilateral and 13 contralateral).
However, we observed no significant association between the GSTT1 and GSTP1 polymorphisms and response to chemotherapy and OS in patients with breast cancer.
Data from this study suggest that increased hypermethylation of GSTP1, ID4, TWIST, DAPK, PAX5 and HIN-1 genes in TNBC than in non-TNBC can act as useful biomarker for BCs in the Saudi population.
The purpose of this study was to determine the frequencies of polymorphisms in the genes GSTM1, GSTT1, GSTP1, and GSTM3 and to investigate whether an association exists between these genes and breast cancer risk in subjects from northeastern Mexico.