Sodium Butyrate Induces CRC Cell Ferroptosis via the CD44/SLC7A11 Pathway and Exhibits a Synergistic Therapeutic Effect with Erastin

Abstract

Colorectal cancer (CRC) is one of the most common malignancies, and effective treatment and prevention methods are lacking. Sodium butyrate (NaB) is a short-chain fatty acid produced by intestinal microbial fermentation of dietary fiber. It has been shown to be effective in inhibiting CRC, but the mechanism is not known. Methods: Human normal intestinal epithelial cell line FHT and colorectal tumor cell line HCT-116 were treated with NaB alone or in combination with different programmed cell death inhibitors. Cell activity was then assessed with MTT assays and PI staining; ferroptosis with Fe2+, glutathione (GSH), and lipid peroxidation assays; signaling pathway screening with PCR arrays; and CD44, SCL7A11, and GPX4 expression with Western blotting. A CD44-overexpressing HCT-116 cell line was constructed to determine the effect of the overexpression of CD44 on NaB-induced ferroptosis. The synergistic effect of co-treatment with NaB and Erastin was assessed by isobolographic analysis. Results: NaB induced apoptosis and ferroptosis in HCT-116 cells but only induced low-level apoptosis in FHC cells. Moreover, NaB significantly increased intracellular Fe2+ and promoted GSH depletion and lipid peroxidation in HCT-116 cells. Ferroptosis-related qPCR array analysis identified CD44/SLC7A11 as a potential effector molecular of NaB-induced ferroptosis. NaB significantly inhibited the expression of CD44 and SLC7A11 in mouse CRC tissues. A CD44 overexpressed HCT-116 cell line was used to verify that CD44/SLC7A11 was a key signaling pathway that NaB-induced GSH depletion, lipid peroxidation accumulation, and ferroptosis in HCT-116 cells. Examination of whether NaB can increase the effect of ferroptosis agents showed that NaB, in combination with Erastin, a ferroptosis inducer, further promoted HCT-116 cell death and increased changes of ferroptosis markers. Conclusions: Our results suggest that NaB induces ferroptosis in CRC cells through the CD44/SLC7A11 signaling pathway and has synergistic effects with Erastin. These results may provide new insights into CRC prevention and the combined use of NaB and ferroptosis-inducing agents.

Genetic markers associated with ferroptosis in Alzheimer’s disease

“…Interestingly, CD44 is listed as one of the suppressors in the FerrDb database, and typically plays a negative regulatory role in biological processes. Several pieces of research have highlighted the role of ferroptosis in AD, with an increase in CD44 expression believed to be involved in the development of disease through this pathway ( Bian et al, 2023 ; Ye et al, 2023 ). However, the precise mechanism of CD44 mediated AD by ferroptosis is still a controversial topic.…”

The efficacy of ferroptosis-inducing compounds IKE and RSL3 correlates with the expression of ferroptotic pathway regulators CD71 and SLC7A11 in biliary tract cancer cells

“…The in silico analysis also revealed an upregulation of SLC7A11 in BTC patients, which was associated with higher pathological tumor grading, disease progression and worse outcome, in contrast to the in silico findings for CD71. Interestingly, protein-protein interaction analysis revealed a relationship between the non-iron and non-ferroptosis related proteins B2M, CD44 and HSPA8 with SLC7A11 and CD71, with CD44 appearing to play an important role in carcinogenesis and prognosis in BTC [ 60 ] and to be an interesting target alone [ 61 ] or in combination with a ferroptosis inhibitor as recently shown [ 62 ]. SLC7A11 is a negative regulator of ferroptosis, and its higher expression is associated with ferroptosis resistance [ 63 – 65 ].…”

Ferroptosis: A therapeutic opportunity of inflammatory bowel disease

“…The signi cance of intestinal microbial metabolites in regulating ferroptosis in IBD is therefore profound. [17] The understanding of ferroptosis in the development and pathogenesis of IBD made signi cant progress in recent years. Further exploration is needed to ascertain whether speci c regulatory agents or signaling pathways are directly associated with ferroptosis in IBD.…”

“…The significance of intestinal microbial metabolites in regulating ferroptosis in IBD is therefore profound. [17]…”