Additionally, the role of QC-dependent apoptosis, cell death, and major potential molecular mechanisms (for example, MAPK/ERK1/2 pathways, p53 pathway, and AMPKα1/ASK1/p38 pathway) for quercetin-induced cancer and cancer stem cell death is evaluated, and lastly, the future directions and precise investigations that are required to make quercetin a safe and effective anticancer pharmaceutical product are highlighted. This evidence concerns the gene MAP3K5 and cancer.