Introduction. Chemotherapy-associated executive dysfunction is an adverse effect of conventional antineoplastic treatment that affects many patients. It has been reported that the presence of specific polymorphisms in key genes can cause a greater susceptibility to develop this condition. Objective. To determine the relationship between the Val66Met polymorphism (196 G>A) of the BDNF gene and the development of executive dysfunction in female patients with breast cancer treated with chemotherapy. Methods. 73 female breast cancer patients were evaluated for executive dysfunction before and after chemotherapy. The evaluation was carried out with the INECO Frontal Screening test (IFS). The genotype (GG=Val/Val, GA=Val/Met and AA=Met/Met) was determined by PCR and sequencing of BDNF gene. Association analysis was performed by calculating the Odds Ratio (OR) and by quantitative comparison. Re...

Background: Cell-free DNA (cfDNA) is used in clinical research to identify biomarkers for diagnosis of and follow-up on cancer. Here, we propose a fast and innovative approach using traditional housekeeping genes as cfDNA targets in a copy number analysis. We focus on the application of highly sensitive technology such as digital PCR (dPCR) to differentiate breast cancer (BC) patients and controls by quantifying regions of PUM1 and RPPH1 (RNase P) in plasma samples. Methods: We conducted a case-control study with 82 BC patients and 82 healthy women. cfDNA was isolated from plasma using magnetic beads and quantified by spectrophotometry to estimate total cfDNA. Then, both PUM1 and RPPH1 genes were specifically quantified by dPCR. Data analysis was calibrated using a reference genomic DNA in different concentrations.Results: We found RNase P and PUM1 values were correlated in the patient g...

Background: Promoter hypermethylation is one of the enabling mechanisms of hallmarks of cancer. Tumor suppressor genes like RARB and GSTP1 have been reported as hypermethylated in breast cancer tumors compared with normal tissues in several populations. This case–control study aimed to determine the association between the promoter methylation ratio (PMR) of RARB and GSTP1 genes (separately and as a group) with breast cancer and its clinical-pathological variables in Peruvian patients, using a liquid biopsy approach. Methods: A total of 58 breast cancer patients and 58 healthy controls, matched by age, participated in the study. We exacted cell-free DNA (cfDNA) from blood plasma and converted it by bisulfite salts. Methylight PCR was performed to obtain the PMR value of the studied genes. We determined the association between PMR and breast cancer, in addition to other clinicopathologi...