RB1 and breast cancer: Thus, c-Kit, a receptor tyrosine kinase that induces the migration of triple-negative BC (TNBC) cells [9], has been identified as overexpressed in African American women (AAW) with BC compared to Caucasian American women (CAW) patients, while Rb, known to inhibit tumor progression, have a lower prevalence in the serum of AAW compared to CAW with BC.