KRAS and neoplasm: Interestingly, gene set enrichment analysis (GSEA) of the DEGs in MCF7 cells treated with vehicle vs. leptin20 or tamoxifen-sensitive vs. tamoxifen-resistant MCF7 cells21 showed a positive enrichment of similar tumor growth-associated pathways (MYC and KRAS) in leptin-treated MCF7 cells as well as tamoxifen-resistant MCF7 cells (Fig. 1N).