ERBB2 and breast cancer: We investigated the expression level of CACNG4, PKMYT1, EPYC, and CHRNA6 genes in breast cancer patients categorized by Scarff-Bloom and Richardson grade status (SBR1, SBR2, and SBR3), BRCA1/2 status (Wild type and Mutated), and PAM50 subtypes (Basal-like, HER-2, Luminal A, Luminal B, and Normal breast-like) using the Breast Cancer Gene-Expression Miner v4.8 databases (bc-GenExMiner v4.8) (see Additional files 6 & 7).