An increasing number of RNA-based classifications, such as the Radiosensitivity Index (RSI) based on a 10-gene signature, also can predict a tumor’s radiosensitivity, although formal validation of these methods in NSCLC has not been conducted.172 Radioresistance may also be associated with highly hypoxic tumors characterized by high levels of HIFs, genomic instability involving interactions between the unfolded protein response (UPR) and mTOR, and ferroptosis-associated genes,173 as well as upregulated lactate metabolism. The gene discussed is MTOR; the disease is neoplasm.