Objective: Metformin as a common antidiabetic drug, has recently found to exert its anti-cancer and immunomodulatory effect in numerous preclinical studies. This study aims to clarify the prognostic impact of metformin use in solid cancer patients receiving immune checkpoint inhibitors (ICIs).Methods: A retrospective cohort enrolling 516 solid cancer patients who received ICI-based therapy between 2018 and 2023 at three hospitals was analyzed. The primary endpoints included overall survival (OS) and progression-free survival (PFS). In addition, a bioinformatics analysis based on TCGA and GSE cohort was performed to investigate the prognostic significance of metformin target genes (MTGs) and their correlation with immune infiltration in non-small cell lung cancer (NSCLC) patients.Results: In the entire cohort, a total of 76 patients received metformin before and/or during ICI therapy. The global analysis demonstrated that metformin use was unrelated with the OS (p = 0.064) and PFS (p = 0.059) of ICI-treated cancer patients, which was confirmed in the subgroups of esophagus, hepatobiliary or pancreatic cancer (all p > 0.05). However, metformin use was significantly correlated with better OS (p = 0.012) and PFS (p = 0.005) in ICI-treated lung cancer patients. Metformin use was also identified as an independent favorable prognostic factor for these patients. The bioinformatics analysis identified five favorable prognostic MTGs (RPS6KA5, RORA, SH3BP5, NUPR1, and CD40LG) for NSCLC patients, all of which was downregulated in lung cancer tissues as compared with normal tissues. The expressions of five MTGs not only could effectively stratify the OS of NSCLC patients, but also was correlated with infiltration of immune cells such as CD4⁺ and CD8⁺ T cells.Conclusion: Metformin use was significantly correlated with better OS and PFS in ICI-treated lung cancer patients. MTGs has the potential to serve as novel clinical biomarkers or druggable targets for cancer immunotherapy. Considering study limitations, the actual impact of metformin use on ICI therapy needs to be clarified by more clinical trials.

Objective: Statins are commonly used for cardiovascular diseases and recent studies have supported their anti-cancer role in numerous human malignancies. This study aims to investigate their prognostic impact in lung cancer patients receiving immune checkpoint inhibitors (ICIs).Methods: A retrospective analysis was performed based on the clinical data from 235 lung cancer patients who received ICI therapy between 2019 and 2024 in three hospitals. The correlation of statin use with overall survival (OS) or progression-free survival (PFS) was analyzed. Then, a comprehensive bioinformatics analysis was used to identify prognostic target genes of statins and investigate their correlation with immune infiltration, followed by validation in an independent cohort and cellular experiments.Results: In the whole cohort, 80 patients (34.0%) received statins. The statin users had a significantly better OS and PFS than the non-statin users. Statin use was an independent favorable prognostic factor for ICI-treated lung cancer patients. Transcription factor RAR-related orphan receptor alpha (RORA) was identified as a favorable prognostic target gene of statins. RORA was found to be downregulated in lung cancer tissues and correlated with infiltration of some immune cells. In the validation cohort, RORA expression was positively correlated with CD8⁺ T cell infiltration in lung cancer tissues, and improved prognosis in lung cancer patients receiving ICIs. Atorvastatin treatment increased RORA expression and RORA knockdown partly antagonized the inhibitory role of Atorvastatin on the malignant characteristics of lung cancer cells in vitro.Conclusion: Statin use was significantly correlated with improved prognosis in lung cancer patients receiving ICIs. Statins may enhance ICI efficacy partly through RORA. Due to study limitations, the actual role of statins and their target genes in anti-cancer immunity needs further investigations.

Radiation enteritis (RE) is a severe adverse reaction after abdominal and pelvic radiotherapy, with a complicated pathogenesis and no effective treatment. Although gut microbiota dysbiosis was reported to play a critical role in RE, related molecular characteristics and intervention strategies have not been extensively summarized. In this review, the mechanisms of RE, including injury to intestinal stem cells, damage to the vascular endothelium, reshaped immune microenvironment, and mucosal barrier dysfunction, are discussed. In addition, radiation-induced gut microbiota dysbiosis is characterized by decreased abundance of beneficial bacteria such as Faecalibacterium prausnitzii and Bifidobacterium bifidum, and increased abundance of detrimental bacteria such as Escherichia-Shigella and Enterococcus. Beneficial and detrimental bacteria affect the development of RE by regulating inflammatory signaling pathways such as NF-κB and JAK/STAT3, and through their metabolites such as bile acids and short-chain fatty acids. Accordingly, several microbiome-targeted therapeutic strategies, including antibiotic administration, dietary interventions, fecal microbiota transplantation, probiotic administration and engineered bacteria, have been developed to mitigate RE. However, some challenges still remain for these therapeutic strategies. The goal of this review is to highlight the crucial role of gut microbiota dysbiosis in the pathogenesis of RE, thereby accelerating the development of individualized microbial therapies against this disease.

Emerging evidence suggests dietary interventions regulate inflammatory signaling through gut microbiome modulation, yet their therapeutic potential in radiation-induced intestinal injury (RIII) remains underexplored. This study demonstrates that ketogenic diet (KD), a high-fat and low-carbohydrate dietary regimen, exerts protective effects against RIII through dual mechanisms involving microbial regulation and inflammatory pathway inhibition. Using high-salt diet (HSD) as a dietary control, KD significantly attenuated intestinal inflammation by downregulating pro-inflammatory cytokines while enhancing barrier integrity through tight junction protein upregulation in radiation-exposed murine model. 16S rDNA sequencing showed KD enriched Akkermansia and reduced Enterobacteriaceae, whereas HSD exhibited inverse patterns. Mechanistically, RNA sequencing revealed that KD uniquely suppressed the JAK2/STAT3 pathway in RIII mice. In vitro studies demonstrated that β-hydroxybutyrate, a key ketone metabolite, effectively suppressed RORγt expression and subsequent downregulation of IL-17A gene transcription via the inhibition of JAK2/STAT3 pathway, thus mitigate inflammatory damage. Fecal microbiota transplantation validated that KD-modified microbiome directly inhibited JAK2/STAT3 signaling activation, as well as the downregulation of RORγt and IL-17A. These findings establish KD as a promising dietary strategy mitigate acute RIII through synergistic modulation of gut microbiota and inflammatory signaling, providing novel insights into nutritional approaches targeting microbial-host crosstalk in radiation injury.

Previous studies have demonstrated a close association between gut microbiota and the onset and progression of colorectal cancer (CRC). However, the progno