MTOR and cancer: Also, the link between obesity and increased cancer risk and worse outcomes may be partly explained by Regulated in Development and DNA Damage Responses 1 (REDD1), which downregulates mTORC1 [28] and is induced by obesity [29]; its overexpression correlates with tumor survival, invasion/metastasis, treatment resistance, and poorer prognosis across multiple malignancies, including breast cancer, pointing to an mTOR-centered mechanistic pathway [30,31,32,33].