Efficacy and Toxicity of Vincristine and CYP3A5 Genetic Polymorphism in Rhabdomyosarcoma Pediatric Egyptian Patients.

BACKGROUND: Rhabdomyosarcoma (RMS) is a rare cancer that develops in soft tissue, particularly skeletal muscle tissue and occasionally hollow organs like the bladder or uterus. Vincristine (VCR) is the main therapy used in treatment of RMS, it is an alkaloid produced from vinca and it is one of the most commonly prescribed drugs in pediatric oncology for the treatment of a number of tumors. The CYP3A5 enzyme is responsible for vincristine metabolism. The effect of CYP3A5 genetic polymorphism on the efficacy and toxicity of VCR on RMS patients still needs further research. METHODS: Genotyping for CYP3A5 SNPs rs776746, rs10264272 and rs41303343 was performed using Taqman Real-Time PCR assays in a retrospective cohort study of 150 RMS pediatric patients treated with vincristine. The relationship between these genotypes and RMS survival was then examined. RESULTS: We found that patients with CYP3A5*3/*3 had the highest incidence of vincristine-induced neuropathy reaching 61.3%. Patients with CYP3A5*1/*3, CYP3A5*3/*6 and the normal metabolizers with CYP3A5*1/*1 had frequencies of 22%, 10.7%, and 4.7%. patients with the lowest frequency of 1.3% were those with the CYP3A5*1/*6 genotype. There was no correlation between the genotypes of CYP3A5*3, CYP3A5*6, CYP3A5*7, and RMS survival. Initial risk, metastasis, response, convulsions, unsteady gait and hepatotoxicity grade had a significant effect on overall survival with p<0.05. CONCLUSION: CYP3A5*1/*1 have less severe vincristine-induced neuropathy than CYP3A5 *1/*3, CYP3A5 *1/*6 and CYP3A5 *3/*3, CYP3A5 *3/*6. There is a significant influence of CYP3A5 mutation on neuropathy grade and assist of ADL as a part of neurotoxicity.

MicroRNAs 182 and 375 Sera Expression as Prognostic Biochemical Markers in Breast Cancer.

INTRODUCTION: Breast cancer (BC) is the most common malignancy among women; supporting the need for identification of novel prognostic biomarkers, circulating microRNAs (miRNAs) could serve as such in various cancers. The aim of this study was to explore the association between miRNAs 182 and 375 with BC stages and its receptors, based on their expression using real time PCR. MATERIALS AND METHODS: Detailed medical history was taken and blood samples were withdrawn from 80 female subjects divided over the studied groups. Patients ranged in age from 24 to 80 years and were classified as follows: group I included 10 noncancerous postmenopausal control subjects; group II included 32 postmenopausal patients with BC; group III included 10 noncancerous premenopausal control subjects; group IV included 24 premenopausal patients with BC; and group V included 6 patients with benign breast tumors. RESULTS: miRNA 182 expression was significantly higher in group II, group IV, and group V (3.36 ± 0.14, 2.52 ± 0.34, and 4.93 ± 0.3,9 respectively); miRNA 375 expression was significantly higher in group II, group IV, and group V (4.41 ± 0.40, 3.12 ± 0.35, and 11.28 ± 2.37, respectively) (P < .05). Both miRNAs were significantly associated with each other and with receptors used for the prognosis of BC even after multiple regression analysis. CONCLUSION: Accordingly, miRNAs 182 and 375 could be potential noninvasive markers used for the follow up of BC patients.