Evidence of a Genomic Biomarker in Normal Human Epithelial Mammary Cell Line, MCF‐10A, That Is Absent in the Human Breast Cancer Cell Line, MCF‐7

This study investigated the use of DNA amplificationfingerprinting (DAF) to identify biomarkers useful in theelucidating genetic factors that lead to carcinogenesis. The DNAamplification fingerprinting (DAF) technique was used to generatefingerprint profiles of a normal human mammary epithelial cellline (MCF-10A) and a human breast cancer cell line (MCF-7).When compared with one another, a polymorphic biomarker gene(262 base pairs (bps)) was identified in MCF-10A but was not present in MCF-7. This gene was cloned from the genomic DNA ofthe MCF-10A cell line, and subjected to Genbank databaseanalysis. The analysis of the nucleotide sequence polymorphicmarker (Genbank account: AC079630) shows that this biomarker has 100% homology with the nucleotide sequence of humanchromosome 12 BAC RP11-476D10 (bps 19612-19353). The nucleotide sequence was used for possible protein translationproduct and the result obtained indicated that the gene codes forhypothetical protein XF2620. In order to evaluate the effects that the 262 bps biomarker would have on the morphology ofMCF-7 cells, it was transfected into MCF-7 cells. There were observable changes in the morphology of the transfected cells. These changes included an increase in cell elongation and a decrease in cell aggregation