SCD and breast carcinoma: SCD1, a rate-limiting enzyme which catalyzes the conversion of saturated fatty acids (SFA) to monounsaturated fatty acids (MUFA) in the fatty acid synthesis pathway [3], is involved in the occurrence and development of various tumors such as lung cancer, breast cancer, prostate cancer, renal cell carcinoma and hepatocellular carcinoma [4,5,6,7,8,9].