Decoding The Genetic Alterations In Cytochrome P450 Family 3 Genes And Its Association With HNSCC

Cytochrome P450 (CYPs) are enzymes belonging to the family of heme-containing proteins, most commonly found in the endoplasmic reticulum and mitochondria. These enzymes catalyze a variety of functions including metabolism of steroids, fatty acids, natural compounds, drugs and carcinogenic chemicals. The inherent association of CYPs with disease conditions have turned the focus into the genetic alterations or variations associated with phenotypes such as drug responsiveness, chemical toxicity and bioconversion of procarcinogens to active carcinogens.

A total of 8 genes of the CYP3 family were analyzed, among which 4 genes were found to harbour gross abnormalities and variations. The genes CYP3A4, CYP3A5, CYP3A7, CYP3A43 showed a common pattern of gene amplification in a group of patients. Truncating and missense variants were also identified of which rs199908125 of CYP3A4 and rs768530577 of CYP3A5 were reported in different populations.

The present observation study utilizes several computational tools to identify and predict the possible outcomes of gene alterations in CYP3 family of genes with head and neck squamous cell carcinoma (HNSCC). cBioportal hosts an exhaustive collection of datasets of various cancers which was the primary source of analysis. Oncoprint data obtained was further analysed using tools such as PROVEAN, I-Mutant and gnomAD.

The gnomAD analysis revealed a few polymorphic rare variants with minor allele frequency less than 0.01, which could have a putative association with HNSCC. Five out of eight variants identified were found to be deleterious exhibiting decreased protein stability.

Further screening of the genetic abnormalities through experimental validation in different populations are warranted to derive an association between the gene identifiers and disease phenotype.