Low prevalence of Caveolin-1 oncogenic polymorphism G14713A and T29107A among breast cancer patient in Sanglah General Hospital

Background: Currently, breast cancer is one of the most common cancers among women, surpassing only by cervical cancer. Despite the improvement in terms of survivability as well as prognosis, most patients are coming with advanced disease at the time of diagnosis. Unlike early disease, determining the outcome of advanced disease is still challenging. Initial investigation showed that polymorphism within caveolin-1 gene could also contribute in determining risk as well as prognosis. In our initial study, we investigated the prevalence of two oncogenic polymorphism of Caveolin-1: SNP CAV1 G14713A and T29107A. Method: The samples were obtained by consecutive sampling in Sanglah Hospital from January 2016 to December 2016. The blood samples were collected in EDTA tube and the DNA was isolated using Promega Kyt. Subsequent PCR was conducted to amplify the gene which then sequenced in Genetika Science. Result: We enrolled 43 samples with complete medical records in our analysis. The mean age in our sample was 49.11±10.33 years and mostly stadium III cancer (39.7%) and poorly differentiated. 68% of our sample were luminal types and the rests were HER2 and TNBC with comparable proportion. We only detect one heterozygous sample for G14713A polymorphism in which the patient had Luminal A type but with high Ki67 and poorly differentiated. For T29107A, we detect two heterozygous individuals and one homozygous individual, all with the same characteristics with G14713A. Conclusion: The prevalence of SNP CAV1 G14713A and T29107A were considerably low in breast cancer population in Bali. However, the characteristic of the samples with the polymorphism suggest that further investigation is needed to confirm their effect in brest cancer morphology.