Cisplatin resistance in bladder cancer (BCa) is driven by metabolic reprogramming that enhances glycolysis and lactate production. Here, we report that lactate-induced histone H3K18 lactylation (H3K18la) drives chemoresistance by activating a novel signaling axis that couples epigenetic regulation with mitochondrial quality control. Through integrative multi-omics analysis, ChIP-qPCR, and promoter reporter assays, we identified HNRNPF as a key functional effector downstream of H3K18la. Unexpectedly, HNRNPF, primarily known as an RNA-binding protein, promotes chemoresistance through a non-canonical mechanism: it directly interacts with the core mitophagy protein Parkin. Mechanistically, the RRM2 domain of HNRNPF binds the R0 domain of Parkin, facilitating Parkin's recruitment to damaged mitochondria. This interaction potentiates Parkin's E3 ubiquitin ligase activity, leading to enhanced ubiquitination of VDAC1 and robust activation of mitophagy. Collectively, our findings establish the H3K18la-HNRNPF-Parkin axis as a previously unrecognized signaling cascade that bridges epigenetic reprogramming and mitochondrial quality control in chemoresistance. Targeting this axis, particularly the HNRNPF-Parkin interaction or mitophagy activation, presents a novel therapeutic strategy to overcome cisplatin resistance in BCa.
BACKGROUND:Bladder cancer (BCa) is a prevalent urinary malignancy with unmet clinical therapeutic needs. Shikonin, a natural anti-tumor compound, exerts anti-BCa activity, yet its direct molecular target and underlying mechanism remain undefined. PURPOSE:This study aimed to identify the direct target of shikonin in BCa and to elucidate the mechanism by which shikonin suppresses tumor progression. METHODS:The anti-BCa effects of shikonin were assessed in vitro and in vivo. Drug affinity responsive target stability (DARTS) combined with 4D quantitative proteomics identified shikonin's direct target, which was validated by molecular docking and cellular thermal shift assay (CETSA). Gain- and loss-of-function experiments and ER-phagy-related assays elucidated the underlying molecular mechanism. RESULTS:Shikonin inhibited BCa cell proliferation, migration, invasion and induced senescence in vitro, and suppressed tumor growth in vivo with no obvious toxicity. Deoxyribonuclease 2 (DNASE2) was identified as shikonin's direct target; shikonin promoted DNASE2 ubiquitination and degradation without altering its mRNA level. DNASE2 was highly expressed in BCa and correlated with poor prognosis, and its knockdown mimicked and enhanced shikonin's anti-BCa effects. Mechanistically, shikonin targeted DNASE2 to downregulate Reticulon 3 (RTN3), thereby inhibiting RTN3-dependent endoplasmic reticulum autophagy (ER-phagy) in BCa. CONCLUSION:This study first identifies DNASE2 as the direct target of shikonin in BCa, and reveals that shikonin exerts anti-BCa activity by promoting DNASE2 ubiquitination/degradation to inhibit the DNASE2/RTN3 axis-mediated ER-phagy. The DNASE2/RTN3 axis is a novel ER-phagy regulatory node in BCa, providing a potential therapeutic target for BCa treatment.
INTRODUCTION:Sepsis is a life-threatening dysregulated host response to infection, lacks effective therapies. ChaC glutathione-specific γ-glutamylcyclotransferase 1 (CHAC1) is elevated in sepsis and correlates with severity, but its functional role in the pathogenesis of sepsis-induced organ damage is unclear. OBJECTIVES:We aimed to define the contribution of CHAC1 to sepsis-induced organ injury and elucidate the underlying mechanisms involving gut microbiota-derived metabolites and host immunity. METHODS:Chac1-/- mice were subjected to LPS-induced endotoxemia to evaluate organ injury. The gut microbiota's role was defined by 16S rRNA gene sequencing, microbiota depletion and fecal microbiota transplantation (FMT). The effect of microbiota-derived metabolite indole-3-carboxylic acid (ICA) was assessed in vivo. Underlying mechanisms were investigated via macrophage depletion, AHR pharmacological/genetic inhibition, and in vitro studies with RAW264.7 cells and bone marrow-derived macrophages. RESULTS:Serum CHAC1 was elevated in septic patients and mice, correlating with disease severity. Chac1 deficiency protected against sepsis-induced multi-organ injury, an effect that was gut microbiota-dependent. Chac1-/- mice exhibited a remodeled gut microbiota, with enrichment of Akkermansia muciniphila and increased levels of the tryptophan metabolite ICA. Exogenous ICA or A. muciniphila supplementation recapitulated the protective phenotype. ICA treatment improved survival, attenuated inflammation, and reduced organ injury by activating the aryl hydrocarbon receptor (AHR) in macrophages. This was evidenced by AHR nuclear translocation, and siRNA-mediated AHR knockdown abolished ICA's effects. ICA reprogrammed macrophage metabolism, inhibiting glycolysis (reduced lactate) and enhancing oxidative phosphorylation (increased ATP, oxygen consumption rate), leading to suppressed pro-inflammatory responses. CONCLUSION:Chac1 deficiency confers sepsis resistance by enriching protective gut microbiota and elevating ICA, which acts as a major downstream effector. ICA activates the AHR in macrophages, driving a metabolic shift from glycolysis to oxidative phosphorylation that dampens inflammation and organ injury. This CHAC1-microbiota-ICA-AHR-macrophage axis identifies ICA as a promising therapeutic candidate and CHAC1 as a potential prognostic biomarker for sepsis.
Intestinal ischemia/reperfusion (I/R) injury is a critical clinical syndrome precipitated by the restoration of blood flow following intestinal ischemia, a common occurrence in perioperative settings such as abdominal aortic surgery, hemorrhagic shock, and cardiopulmonary bypass. This injury extends beyond the local gut, as the disruption of the intestinal mucosal barrier facilitates bacterial and endotoxin translocation into the systemic circulation, triggering a systemic inflammatory response that can progress to sepsis and multiple organ dysfunction syndrome (MODS). Despite advances in critical care, the mortality rate associated with severe intestinal I/R injury remains formidable. The microcirculatory disturbances and organ damage following intestinal I/R involve complex pathological processes, including metabolic injury and oxidative stress. In recent years, rapid developments in the understanding of cell death mechanisms, gut microbiota, microRNAs, and fundamental medical technologies have significantly advanced research on the prevention and treatment of I/R injury. This review aims to comprehensively summarize the occurrence and progression of intestinal I/R, its impact on extraintestinal organ injury, diagnostic strategies and biomarkers, as well as current treatment methods, thereby providing guidance for the future prediction, diagnosis, and treatment of intestinal I/R injury.
Although multiple therapeutic modalities, including surgery, chemotherapy, radiotherapy, immunotherapy, and targeted therapy, have improved the management of bladder cancer, the clinical outcome of muscle-invasive bladder cancer (MIBC) remains unsatisfactory. To address this challenge, we identified MIBC-related genes (MIBC.RGs) through transcriptomic and proteomic analyses and developed a prognostic model to predict patient outcomes. Among the candidate genes, PSMG1 was prioritized through an integrated framework combining machine learning-based screening and single-cell transcriptomic analysis. Experimental analyses revealed that PSMG1 was markedly upregulated in bladder cancer (BCa), progressively upregulated from normal tissue to MIBC, and PSMG1 silencing reduced cell proliferation, invasion, and clonogenic capacity in vitro, while attenuating tumor growth in vivo. Mechanistically, our data suggest that PSMG1 may promote BCa aggressiveness, at least in part, by affecting E-cadherin stability and EMT-related signaling. Epigenetic profiling revealed significant H3K18la enrichment at the PSMG1 promoter, supporting a potential H3K18la-PSMG1 regulatory axis. Finally, molecular docking, proteomic profiling, and Drug Affinity Responsive Target Stability (DARTS) assays prioritized Curcumin as a candidate compound potentially associated with PSMG1 targeting. Overall, our findings indicate that the H3K18la-PSMG1 axis may participate in BCa progression and support further evaluation of Curcumin in PSMG1-associated therapeutic strategies.
Glioblastoma (GBM) is a highly aggressive form of brain tumor characterized by dysregulated metabolism. Increased fatty acid oxidation (FAO) protects tumor cells from lipid peroxidation-induced cell death, although the precise mechanisms involved remain unclear. Here, we report that loss of TNF receptor-associated factor 3 (TRAF3) in GBM critically regulated lipid peroxidation and tumorigenesis by controlling the oxidation of polyunsaturated fatty acids (PUFAs). TRAF3 was frequently repressed in GBM due to promoter hypermethylation. TRAF3 interacted with enoyl-CoA hydratase 1 (ECH1), an enzyme that catalyzes the isomerization of unsaturated FAs (UFAs) and mediates K63-linked ubiquitination of ECH1 at Lys214. ECH1 ubiquitination impeded TOMM20-dependent mitochondrial translocation of ECH1, which otherwise promoted the oxidation of UFAs, preferentially the PUFAs, and limited lipid peroxidation. Overexpression of TRAF3 enhanced the sensitivity of GBM to ferroptosis and anti-programmed death-ligand 1 (anti-PD-L1) immunotherapy in mice. Thus, the TRAF3/ECH1 axis played a key role in the metabolism of PUFAs and was crucial for lipid peroxidation damage and immune elimination in GBM.
Liver injury is an independent risk factor for multiple organ dysfunction and high mortality in patients with sepsis. However, the pathological mechanisms and therapeutic strategies for sepsis-associated liver injury have not been fully elucidated. Time-restricted feeding (TRF) is a promising dietary regime, but its role in septic liver injury remains unknown. Using 16S rRNA gene sequencing, Q200 targeted metabolomics, transcriptomics, germ-free mice, Hmgcs2/Lpin1 gene knockout mice, and Aml12 cells experiments, we revealed that TRF can mitigate septic liver injury by modulating the gut microbiota, particularly by increasing Lactobacillus murinus (L. murinus) abundance, which was significantly reduced in septic mice. Further study revealed that live L. murinus could markedly elevate serum levels of metabolite 3-hydroxybutyrate (3-HB) and alleviate sepsis-related injury, while the knockout of the key enzyme for 3-HB synthesis (3-hydroxy-3-methylglutaryl-CoA synthase 2, Hmgcs2) in the liver negated this protective effect. Additionally, serum 3-HB levels were significantly positively correlated with L. murinus abundance and negatively correlated with liver injury indicators in septic patients, demonstrating a strong predictive value for septic liver injury (AUC = 0.8429). Mechanistically, 3-HB significantly inhibited hepatocyte ferroptosis by activating the PI3K/AKT/mTOR/LPIN1 pathway, reducing ACSL4, MDA, LPO, and Fe2+ levels. This study demonstrates that TRF reduces septic liver injury by modulating gut microbiota to increase L. murinus, which elevates 3-HB to activate PI3K/AKT/mTOR/LPIN1 and inhibit hepatocyte ferroptosis. Overall, this study elucidates the protective mechanism of TRF against septic liver injury and identifies 3-HB as a potential therapeutic target and predictive biomarker, thereby providing new insights into the clinical management and diagnosis of septic liver injury.
Background Chronic stress is well known to promote tumor progression, however, little is known whether chronic stress-mediated regulation of osteoblasts contributes to the migration and invasion of metastatic cancer cells. Methods The proliferation, migration and invasion of prostate cancer cells were assessed by CCK-8 and transwell assay. HIF-1α expression of osteoblasts and epithelial-mesenchymal transition (EMT) markers of prostate cancer cells were examined by Western blot. The mRNA level of cytokines associated with bone metastasis in osteoblasts and EMT markers in PC-3 and DU145 cells were performed by qRT-PCR. Functional rescue experiment of cells were performed by using siRNA, plasmid transfection and inhibitor treatment. Results Isoproterenol (ISO), a pharmacological surrogate of sympathetic nerve activation induced by chronic stress, exhibited no direct effect on migration and invasion of PC-3 and DU145 prostate cancer cells. Whereas, osteoblasts pretreated with ISO promoted EMT, migration and invasion of PC-3 and DU145 cells, which could be inhibited by β2AR inhibitor. Mechanistically, ISO increased the secretion of CXCL12 via the β2AR-HIF-1α signaling in osteoblasts. Moreover, overexpression of HIF-1α osteoblasts promoted migration and invasion of PC-3 and DU145 cells, which was inhibited by addition of recombinant knockdown of CXCR4 in PC-3 and DU145 cells, and inhibiting CXCL12-CXCR4 signaling with LY2510924 blunted the effects of osteoblasts in response to ISO on EMT and migration as well as invasion of PC-3 and DU145 cells. Conclusions These findings demonstrated that β2AR-HIF-1α-CXCL12 signaling in osteoblasts facilitates migration and invasion as well as EMT of prostate cancer cells, and may play a potential role in affecting bone metastasis of prostate cancer.
Bladder cancer (BCa) is a prevalent malignancy with a poor prognosis. SLC7A7 has been linked to BCa progression and angiogenesis, but its specific role remains unclear. We established a SLC7A7-knockdown BCa cell line to investigate its effects on angiogenesis. In vivo experiments assessed tumor vascularization, while in vitro studies explored exosome involvement. MiRNA sequencing identified miR-152-3p as a key regulator. Further investigation using dual-luciferase reporter assays, qRT-PCR, and Western blot revealed that miR-152-3p inhibits the expression of FGFR3 by binding to its 3’ UTR. Meanwhile, functional assays, including angiogenesis assays, Transwell assays, and wound healing assays, were performed to evaluate the effects of miR-152-3p on angiogenesis. We confirmed the significant role of SLC7A7 in BCa progression, specifically in promoting angiogenesis, through the involvement of exosomes and the regulatory axis of miR-152-3p/ FGFR3. Targeting FGFR3 might be a promising strategy to reverse control BCa progression for an improved prognosis.
The small leucine-rich proteoglycan decorin (DCN) is recognized for its diverse roles in tissue homeostasis and malignant progression. Nevertheless, the regulatory effects of DCN on bladder cancer stem cells (BCSCs) and the underlying mechanisms in muscle-invasive bladder cancer (MIBC) remain to be elucidated. The study obtained data (including scRNA-seq, clinicopathological characteristics, and survival) were acquired from TCGA and GEO. The BCSCs were cultured by enriching the suspension culture in a serum-free medium, followed by flow cytometry sorting. Overexpression/knockdown was constructed by utilizing lentivirus. The surface biomarkers of cancer stem cells were identified via flow cytometry. Cell proliferation and self-renewal were evaluated by CCK8 and Sphere formation assays, and in vivo tumor growth was evaluated with subcutaneous xenografts. Total DCN expression was significantly elevated in muscle-invasive bladder cancer (MIBC) and was associated with poor prognosis. The ΔDCN isoform, which lacks glycosylation sites, was identified in bladder cancer stem cells (BCSCs) derived from clinical tissue samples and bladder cancer cell lines. Suppression of ΔDCN expression resulted in a reduction of BCSC stemness. Both in vitro and in vivo experiments indicated that overexpression of full-length DCN inhibited stemness within the extracellular matrix. Conversely, overexpression of ΔDCN and the introduction of exogenous recombinant decorin protein in ΔDCN-knockdown BCSC-SW780 cell lines enhanced stemness within the cytoplasm. The ΔDCN isoform exhibited resistance to gemcitabine chemotherapy in vitro. Non-glycanated ΔDCN isoforms were identified in bladder cancer stem cells (BCSCs), where they exhibited differential cytoplasmic localization and promoted oncogenic effects by inducing a stemness phenotype and conferring resistance to gemcitabine chemotherapy. These oncogenic effects are in stark contrast to the anti-tumor functions of glycosylated DCN in the extracellular matrix. The ratio of ΔDCN isoforms to glycosylated DCN is pivotal in predicting tumor progression and therapeutic resistance.
Patients with bladder cancer (Bca) frequently acquires resistance to platinum-based chemotherapy, particularly cisplatin. This study centered on the mechanism of cisplatin resistance in Bca and highlighted the pivotal role of lactylation in driving this phenomenon. Utilizing single-cell RNA sequencing, we delineated the single-cell landscape of Bca, pinpointing a distinctive subset of Bca cells that exhibit marked resistance to cisplatin with association with glycolysis metabolism. Notably, we observed that H3 lysine 18 lactylation (H3K18la) plays a crucial role in activating the transcription of target genes by enriching in their promoter regions. Targeted inhibition of H3K18la effectively restored cisplatin sensitivity in these cisplatin-resistant epithelial cells. Furthermore, H3K18la-driven key transcription factors YBX1 and YY1 promote cisplatin resistance in Bca. These findings enhance our understanding of the mechanisms underlying cisplatin resistance, offering valuable insights for identifying novel intervention targets to overcome drug resistance in BCa.
Background: In the context of sepsis patients, hypertension has a significant impact on the likelihood of developing sepsis-associated acute kidney injury (S-AKI), leading to a considerable burden. Moreover, sepsis is responsible for over 50 % of cases of acute kidney injuries (AKI) and is linked to an increased likelihood of death during hospitalization. The objective of this research is to develop a dependable and strong nomogram framework, utilizing the variables accessible within the first 24 h of admission, for the anticipation of S-AKI in sepsis patients who have hypertension. Methods: In this study that looked back, a total of 462 patients with sepsis and high blood pressure were identified from Nanfang Hospital. These patients were then split into a training set (consisting of 347 patients) and a validation set (consisting of 115 patients). A multivariate logistic regression analysis and a univariate logistic regression analysis were performed to identify the factors that independently predict S-AKI. Based on these independent predictors, the model was constructed. To evaluate the efficacy of the designed nomogram, several analyses were conducted, including calibration curves, receiver operating characteristics curves, and decision curve analysis. Results: The findings of this research indicated that diabetes, prothrombin time activity (PTA), thrombin time (TT), cystatin C, creatinine (Cr), and procalcitonin (PCT) were autonomous prognosticators for S-AKI in sepsis individuals with hypertension. The nomogram model, built using these predictors, demonstrated satisfactory discrimination in both the training (AUC = 0.823) and validation (AUC = 0.929) groups. The S-AKI nomogram demonstrated superior predictive ability in assessing S-AKI within the hypertension grade I (AUC = 0.901) set, surpassing the hypertension grade II (AUC = 0.816) and III (AUC = 0.810) sets. The nomogram exhibited satisfactory calibration and clinical utility based on the calibration curve and decision curve analysis. Conclusion: In patients with sepsis and high blood pressure, the nomogram that was created offers a dependable and strong evaluation for predicting S-AKI. This evaluation provides valuable insights to enhance individualized treatment, ultimately resulting in improved clinical outcomes.
Background: A conclusive evidence regarding the optimal concentration and volume of local anesthetic for quadratus lumborum block is lacking. Methods: In this single -center, prospective, randomized, controlled study, 60 patients scheduled for laparoscopic colorectal surgery were randomly assigned to 3 different combinations of volume and concentration of ropivacaine (3 mg/kg) - Group 0.25%, Group 0.375% and Group 0.5%. All subjects received ultrasound -guided posterior quadratus lumborum block prior to the induction. The primary outcome was the complete sensory block rate of surgical site measured at 30 min after quadratus lumborum block, after extubation, at 12, 24, and 48 h after operation. Secondary outcomes were the changes in hemodynamic parameters before and after incision ( Delta SBP, Delta DBP and Delta HR), postoperative pain score, the sufentanil consumption after surgery, length of stay and adverse reactions. Results: The sensory block rate of surgical site at 5 time points differed significantly among the three groups ( P < 0.001). Both Group 0.375% ( P < 0.001) and Group 0.5% ( P < 0.001) had a higher sensory block rate than Group 0.25%, but no significant difference was observed between the former two. Group 0.375% and Group 0.5% had lower postoperative pain scores, lower sufentanil consumption after surgery and shorter length of stay. No statistical difference was observed in A SBP, A DBP, A HR and the incidence of adverse reactions. Conclusions: 0.375% and 0.5% ropivacaine in posterior quadratus lumborum block provide better sensory block of surgical site when compared to 0.25% in laparoscopic colorectal surgery.
Amplification of chromosome 7p11 (7p11) is the most common alteration in primary glioblastoma (GBM), resulting in gains of epidermal growth factor receptor (EGFR) copy number in 50 to 60% of GBM tumors. However, treatment strategies targeting EGFR have thus far failed in clinical trials, and the underlying mechanism remains largely unclear. We here demonstrate that EGFR amplification at the 7p11 locus frequently encompasses its neighboring genes and identifies SEC61G as a critical regulator facilitating GBM immune evasion and tumor growth. We found that SEC61G is always coamplified with EGFR and is highly expressed in GBM. As an essential subunit of the SEC61 translocon complex, SEC61G promotes translocation of newly translated immune checkpoint ligands (ICLs, including PD-L1, PVR, and PD-L2) into the endoplasmic reticulum and promotes their glycosylation, stabilization, and membrane presentation. Depletion of SEC61G promotes the infiltration and cytolytic activity of CD8+ T cells and thus inhibits GBM occurrence. Further, SEC61G inhibition augments the therapeutic efficiency of EGFR tyrosine kinase inhibitors in mice. Our study demonstrates a critical role of SEC61G in GBM immune evasion, which provides a compelling rationale for combination therapy of EGFR-amplified GBMs.
Abstract Background Hepatic inflammation is a common initiator of liver diseases and considered as the primary driver of hepatocellular carcinoma (HCC). However, the precise mechanism of inflammation-induced HCC development and immune evasion remains elusive and requires extensive investigation. This study sought to identify the new target that is involved in inflammation-related liver tumorigenesis. Methods RNA-sequencing (RNA-seq) analysis was performed to identify the differential gene expression signature in primary human hepatocytes treated with or without inflammatory stimulus. A giant E3 ubiquitin protein ligase, HECT domain and RCC1-like domain 2 (HERC2), was identified in the analysis. Prognostic performance in the TCGA validation dataset was illustrated by Kaplan–Meier plot. The functional role of HERC2 in HCC progression was determined by knocking out and over-expressing HERC2 in various HCC cells. The precise molecular mechanism and signaling pathway networks associated with HERC2 in HCC stemness and immune evasion were determined by quantitative real-time PCR, immunofluorescence, western blot, and transcriptomic profiling analyses. To investigate the role of HERC2 in the etiology of HCC in vivo, we applied the chemical carcinogen diethylnitrosamine (DEN) to hepatocyte-specific HERC2-knockout mice. Additionally, the orthotopic transplantation mouse model of HCC was established to determine the effect of HERC2 during HCC development. Results We found that increased HERC2 expression was correlated with poor prognosis in HCC patients. HERC2 enhanced the stemness and PD-L1-mediated immune evasion of HCC cells, which is associated with the activation of signal transducer and activator of transcription 3 (STAT3) pathway during the inflammation-cancer transition. Mechanically, HERC2 coupled with the endoplasmic reticulum (ER)-resident protein tyrosine phosphatase 1B (PTP1B) and limited PTP1B translocation from ER to ER-plasma membrane junction, which ameliorated the inhibitory role of PTP1B in Janus kinase 2 (JAK2) phosphorylation. Furthermore, HERC2 knockout in hepatocytes limited hepatic PD-L1 expression and ameliorated HCC progression in DEN-induced mouse liver carcinogenesis. In contrast, HERC2 overexpression promoted tumor development and progression in the orthotopic transplantation HCC model. Conclusion Our data identified HERC2 functions as a previously unknown modulator of the JAK2/STAT3 pathway, thereby promoting inflammation-induced stemness and immune evasion in HCC.
Mesenchymal glioblastoma (GBM) is highly resistant to radio-and chemotherapy and correlates with worse survival outcomes in GBM patients; however, the underlying mechanism determining the mesenchymal phenotype remains largely unclear. Herein, it is revealed that FBXO7, a substrate-recognition component of the SCF complex implicated in the pathogenesis of Parkinson's disease, confers mesenchymal properties and chemoresistance in GBM by controlling Rbfox2-mediated alternative splicing. Specifically, FBXO7 ubiquitinates Rbfox2 Lys249 through K63-linked ubiquitin chains upon arginine dimethylation at Arg341 and Arg441 by PRMT5, leading to Rbfox2 stabilization. FBXO7 controls Rbfox2-mediated splicing of mesenchymal genes, including FoxM1, Mta1, and Postn. FBXO7-induced exon Va inclusion of FoxM1 promotes FoxM1 phosphorylation by MEK1 and nuclear translocation, thereby upregulates CD44, CD9, and ID1 levels, resulting in GBM stem cell self-renewal and mesenchymal transformation. Moreover, FBXO7 is stabilized by temozolomide, and FBXO7 depletion sensitizes tumor xenografts in mice to chemotherapy. The findings demonstrate that the FBXO7-Rbfox2 axis-mediated splicing contributes to mesenchymal transformation and tumorigenesis, and targeting FBXO7 represents a potential strategy for GBM treatment.
Prostate cancer (PCa) is one of the most common cancers in men. Patients with recurrent disease initially respond to androgen-deprivation therapy, but the tumor eventually progresses into castration-resistant PCa. Thus, new therapeutic approaches for PCa resistance to current treatments are urgently needed. Here, we report that cardiac glycoside neriifolin suppresses the malignancy of cancer cells via increasing DNA damage and apoptosis through activation of endoplasmic reticulum stress (ERS) in prostate cancers. We found that cardiac glycoside neriifolin markedly inhibited the cell growth and induced apoptosis in prostate cancer cells. Transcriptome sequence analysis revealed that neriifolin significantly induced DNA damage and double strand breaks (DSBs), validated with attenuation expression of genes in DSBs repair and increasing phosphorylated histone H2AX (γ-H2AX) foci formation, a quantitative marker of DSBs. Moreover, we found that neriifolin also activated ERS, evidenced by upregulation and activation of ERS related proteins, including eukaryotic initiation factor 2α (eIF2α), protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK) and C/EBP homologous protein (CHOP) as well as downregulation of CCAATenhancerbinding protein alpha (C/EBP-α), a transcriptional factor that forms heterodimers with CHOP. In addition, neriifolin treatment dramatically inhibited the by tumor growth, which were reversed by CHOP loss or overexpression of C/EBP-α in nude mice. Mechanistically, neriifolin suppressed the tumor growth by increasing DNA damage and apoptosis through CHOP-C/EBP-α signaling axis of ERS in prostate cancers. Taken together, these results suggest that cardiac glycoside neriifolin may be a potential tumor-specific chemotherapeutic agent in prostate cancer treatment.
Bladder cancer is one of the most common malignancies in the world. Cisplatin is one of the most potent and widely used anticancer drugs and has been employed in several malignancies. Cisplatin-based combination chemotherapies have become important adjuvant therapies for bladder cancer patients. Cisplatin-based treatment often results in the development of chemoresistance, leading to therapeutic failure and limiting its application and effectiveness in bladder cancer. To develop improved and more effective cancer therapy, research has been conducted to elucidate the underlying mechanism of cisplatin resistance. Epigenetic modifications have been demonstrated involved in drug resistance to chemotherapy, and epigenetic biomarkers, such as urine tumor DNA methylation assay, have been applied in patients screening or monitoring. Here, we provide a systematic description of epigenetic mechanisms, including DNA methylation, noncoding RNA regulation, m6A modification and posttranslational modifications, related to cisplatin resistance in bladder cancer.
There are significant differences in the susceptibility of populations to intestinal ischemia/reperfusion (I/R), but the underlying mechanisms remain elusive. Here, we show that mice exhibit significant differences in susceptibility to I/R-induced enterogenic sepsis. Notably, the milnacipran (MC) content in the enterogenic-sepsis-tolerant mice is significantly higher. We also reveal that the pre-operative fecal MC content in cardiopulmonary bypass patients, including those with intestinal I/R injury, is associated with susceptibility to post-operative gastrointestinal injury. We reveal that MC attenuates mouse I/R injury in wild-type mice but not in intestinal epithelial aryl hydrocarbon receptor (AHR) gene conditional knockout mice (AHRflox/flox) or IL-22 gene deletion mice (IL-22-/-). Collectively, our results suggest that gut microbiota affects susceptibility to I/R-induced enterogenic sepsis and that gut microbiota-derived MC plays a pivotal role in tolerance to intestinal I/R in an AHR/ILC3/IL-22 signaling-dependent manner, revealing the pathological mechanism, potential prevention and treatment drugs, and treatment strategies for intestinal I/R.
More than one half melanoma patients have BRAF gene mutation. BRAF inhibitor vemurafenib is an effective medication for these patients. However, acquired resistance is generally inevitable, the mechanisms of which are not fully understood. Cell senescence and senescence-associated secretory phenotype (SASP) are involved in extensive biological functions. This study was designed to explore the possible role of senescent cells in vemurafenib resistance. The results showed that vemurafenib treatment induced BRAF-mutant but not wild-type melanoma cells into senescence, as manifested by positive β-galactosidase staining, cell cycle arrest, enlarged cellular morphology, and cyclin D1/p-Rb pathway inhibition. However, the senescent cells induced by vemurafenib (SenV) did not display DNA damage response, p53/p21 pathway activation, reactive oxygen species accumulation, decline of mitochondrial membrane potential, or secretion of canonical SASP cytokines. Instead, SenV released other cytokines, including CCL2, TIMP2, and NGFR, to protect normal melanoma cells from growth inhibition upon vemurafenib treatment. Xenograft experiments further confirmed that vemurafenib induced melanoma cells into senescence in vivo. The results suggest that vemurafenib can induce robust senescence in BRAFV600E melanoma cells, leading to the release of resistance-conferring cytokines. Both the senescent cells and the resistant cytokines could be potential targets for tackling vemurafenib resistance.