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Ferroptosis is a type of programmed cell death characterized by accumulation of free iron, reactive oxygen species generation and lipid peroxidation and is distinct from other types of regulated cell deaths such as apoptosis, necrosis and autophagy. Ferroptosis is distinct from other programmed cell deaths for its iron dependence and its significant role in tumor suppression. Therefore, harnessing ferroptosis may offer promising avenues for cancer therapy. In the present review, the different pathways that lead to ferroptosis, the genes and transcription factors involved in both iron and lipid metabolism, as well as the impact of small‑molecule alterations on the regulation of ferroptotic cell death, were discussed. Furthermore, the emergence of combination therapies with ferroptosis‑inducing molecules that overcome resistance to conventional chemotherapy, particularly in solid tumors, were highlighted. Show less

SLC7A11/xCT is an antiporter that mediates the uptake of extracellular cystine in exchange for glutamate. Cystine is reduced to cysteine, which is a rate-limiting precursor in glutathione synthesis; a process that protects cells from oxidative stress and is, therefore, critical to cell growth, proliferation, and metabolism. SLC7A11 is expressed in different tissues and plays diverse functional roles in the pathophysiology of various diseases, including cancer, by regulating the processes of redox homeostasis, metabolic flexibility/nutrient dependency, immune system function, and ferroptosis. SLC7A11 expression is associated with poor prognosis and drug resistance in cancer and, therefore, represents an important therapeutic target. In this review, we discuss the molecular functions of SLC7A11 in normal versus diseased tissues, with a special focus on how it regulates gastrointestinal cancers. Further, we summarize current therapeutic strategies targeting SLC7A11 as well as novel avenues for treatment. Show less

The transcription factor NRF2 (nuclear factor-erythroid 2 p45-related factor 2 or NFE2L2) plays a critical role in response to cellular stress. Following an oxidative insult, NRF2 orchestrates an antioxidant program, leading to increased glutathione levels and decreased reactive oxygen species (ROS). Mounting evidence now implicates the ability of NRF2 to modulate metabolic processes, particularly those at the interface between antioxidant processes and cellular proliferation. Notably, NRF2 regulates the pentose phosphate pathway, NADPH production, glutaminolysis, lipid and amino acid metabolism, many of which are hijacked by cancer cells to promote proliferation and survival. Moreover, deregulation of metabolic processes in both normal and cancer-based physiology can stabilize NRF2. We will discuss how perturbation of metabolic pathways, including the tricarboxylic acid (TCA) cycle, glycolysis, and autophagy can lead to NRF2 stabilization, and how NRF2-regulated metabolism helps cells deal with these metabolic stresses. Finally, we will discuss how the negative regulator of NRF2, Kelch-like ECH-associated protein 1 (KEAP1), may play a role in metabolism through NRF2 transcription-independent mechanisms. Collectively, this review will address the interplay between the NRF2/KEAP1 complex and metabolic processes. Show less

Oxaliplatin undergoes extensive non-enzymatic chemical transformation in the body. Complexes with sulphur-containing compounds have previously been found in plasma from patients treated with oxaliplatin. We have studied the kinetics for the reactions between oxaliplatin and cysteine, methionine, and glutathione, by determination of the degradation of oxaliplatin using liquid chromatography with UV-detection. We also studied the degradation of oxaliplatin in plasma ultrafiltrate (PUF). For the degradation of oxaliplatin in the presence of glutathione, methionine, and cysteine, the second-order rate constants were 4.7M(-1)min(-1) (95% confidence interval [C.I.], 4.4-5.0M(-1)min(-1)), 5.5M(-1)min(-1) (95% C.I., 5.2-5.7M(-1)min(-1)), and 15M(-1)min(-1) (95% C.I., 14-17M(-1)min(-1)), respectively. The reaction rate was much faster than previously reported kinetics for cisplatin. The degradation rate of oxaliplatin in PUF was biphasic. The rate constant for the first phase varied from 9.5x10(-3) to 0.13min(-1) and for the second phase from (1.7 to 1.8)x10(-3)min(-1) in PUF from five healthy volunteers. The first hours of the degradation of oxaliplatin in PUF are accounted for by the degradation of oxaliplatin in a cocktail of sodium chloride and sulphur-containing compounds at physiological plasma concentrations. In conclusion, the rate of the reaction of oxaliplatin with three sulphur-containing compounds was faster for oxaliplatin than what is previously known for cisplatin. This may be important with respect to differences in the cellular effects of cisplatin and oxaliplatin treatment. Show less