Cytochrome P450 (CYP1A2) Genetic Polymorphism as a Genetic Marker for Treatment Outcome in Early Breast Cancer Patients

Background: Cytochrome P450(CYP1A2) has a crucial role in drug metabolism, and some neurotoxins. Polymorphisms of Cytochrome P450(CYP1A2) have a role in cancer activity through affecting aromatic hydrocarbon metabolism. This work was aimed at studying CYP1A2 polymorphism as a genetic predictive marker of treatment out come in breast cancer (BC) female cases.

Methods: This case control research included 70 cases. Patients’ group (50 cases) were categorized into two groups: Group I A (n=20): failed BC cases for hormonal therapy during treatment period, group I B (n=30): after 5 years of hormonal treatment which subdivided into two groups: [treatment failure (recurrence or metastasis) and patients with successful outcome] and group II (n=20): normal female subjects.

Results: The occurrence of treatment events was significant in patients carrying Polymorphism of Cytochrome P450(CYP1A2) (CYP1A2 rs762551) C/A. Also, relapse was earlier in patients with CYP1A2 carrying C allele and earlier among CC compared to C/A and wild allele. There was significantly higher in positive family history than in negative ones, with about 85.0% of positive family patients carrying C/A polymorphism and 77.8% in CC polymorphism. The incidence of BC events was studied using Kaplan-Meier scale to study event free survival in relation to CYP1A2 rs 762551 in postmenopausal BC patients treated with AI along five years treatment.

Conclusions: CYP1A2 genetic polymorphism is associated with early treatment events among female cases developing BC treated by aromatase inhibitors.