These results suggest that β2M overexpression downregulates p-CREB/CREB levels and significantly upregulates p-SGK1/SGK1 and Bcl-2 levels, but does not affect HER2, HIF-1α, VEGF, and ERK signaling in ER+ breast cancer cells with HER2−. The gene discussed is BCL2; the disease is breast carcinoma.