METHODS: Blood samples were collected from 75 TNBC patients and 83 controls. Genomic DNA was extracted from blood samples and the SNP genotyping was performed by using PCR-RFLP technique. The genotypes were characterized and grouped into homozygous wildtype, heterozygote and homozygous variant based on the band size. The result was subjected to statistical analysis.
RESULTS: The A allele and AA genotype of ABCG2 421 C>A had OR of 3.011 (p=0.003, 95% CI: 1.417-6.398) and 9.042 (p=0.011, 95% CI: 1.640-49.837), to develop advanced staging carcinoma respectively. The AA genotype of ABCG2 421 C>A polymorphism was also associated with metaplastic and medullary carcinoma with an OR of 6.429 (p=0.018, 95% CI: 1.373-30.109). A significant association was also found in haplotype 34G/421A of ABCG2 with advanced cancer staging as well as metaplastic and medullary carcinoma with OR of 2.347 (p=0.032, 95% CI: 1.010-5.560) and 2.546 (p=0.008, 95% CI: 1.005-6.447), respectively. Conclusion: The present study suggests that ABCG2 421 C>A polymorphism was associated with metaplastic and medullary histology and advanced cancer staging in TNBC patients.
METHODS: We analysed the expression of AR in 97 TNBC cases from Penang General Hospital for a period of 3 years (2014 to 2017). Androgen receptor immunoreactivity was considered positive if ≥ 1% of tumour cells nuclei were stained irrespective of staining intensity.
RESULTS: The prevalence of AR expression in TNBC was 31% (30/97), with the proportion of AR-positive tumour cells ranged from 1% to 90%. These include 23 invasive carcinomas, no special type (NST) and 7 other invasive carcinoma subtypes (papillary, lobular, clear cell and medullary carcinomas). Sixty-seven cases (69%) that showed AR immunonegativity were invasive carcinomas, NST (n=60), clear cell carcinoma (n=1) and metaplastic carcinoma (n=6). Androgen receptor immunoexpression was inversely correlated with tumour grade (p=0.016), but not the tumour stage, tumour size and nodal status.
CONCLUSION: AR is expressed in about one-third of TNBC and loss of AR immunoexpression does not predict adverse clinical outcomes. Larger cohorts for better characterisation of the role of AR immunoexpression in TNBC are warranted.