CPSF6-mediated XBP1 3'UTR shortening attenuates cisplatin-induced ER stress and elevates chemo-resistance in lung adenocarcinoma

E2F7 upregulates MCM4 and fatty acid metabolism to advance lung adenocarcinoma metastasis

BACKGROUND

MCM4, a key protein in MCM, is frequently overexpressed in cancers, but its specific role in lung adenocarcinoma (LUAD) metastasis is unclear.

METHODS

Bioinformatics revealed the mRNA expression pattern of MCM4 in LUAD, which we confirmed in both normal lung epithelial and adenocarcinoma cell lines using qRT-PCR and western blot (WB). Cellular proliferation was gauged by cell counting kit-8 and colony formation assays, and the expression of epithelial-mesenchymal transition markers along with fatty acid synthase (FASN) was probed via WB. We employed Transwell to assess cellular migration and invasion, and utilized kits for quantifying intracellular triglycerides and phospholipids. Bioinformatics identified E2F7 as a potential transcriptional regulator of MCM4, prompting us to explore its relationship with MCM4, including predicted binding sites and E2F7 mRNA expression in LUAD. Chromatin immunoprecipitation and dual-luciferase reporter assays were conducted to validate the regulatory effects of E2F7 on MCM4.

RESULTS

MCM4 was found to be overexpressed in LUAD, and its knockdown inhibited cancer cell proliferation, migration, invasion, and metastasis, along with decreased FASN expression and declined levels of triglycerides and phospholipids within cells. Mechanistically, E2F7 transcriptionally activated MCM4, regulating fatty acid metabolism and promoting LUAD progression and metastasis.

CONCLUSION

Our study elucidates the mechanism by which E2F7 transcriptionally controls MCM4 to activate fatty acid metabolism, fueling LUAD metastasis. These discoveries emphasize the pivotal function of lipid metabolism in LUAD development and suggests new therapeutic targets for LUAD treatment.

m6A-mediated regulation of CPSF6 by METTL3 promotes oxaliplatin resistance in colorectal cancer through enhanced glycolysis

Oxaliplatin resistance poses a significant challenge in colorectal cancer (CRC) treatment. Recent studies have implicated CPSF6 in cancer progression and drug resistance, although its role in chemotherapy resistance and regulatory mechanisms is unclear. This study investigates CPSF6's involvement in oxaliplatin resistance in CRC and its regulation via m6A methylation by METTL3. We assessed CPSF6 expression in oxaliplatin-resistant (OxR) CRC cell lines (HT29-OxR and HCT116-OxR) compared to sensitive counterparts using qRT-PCR and Western blotting. CPSF6 was significantly upregulated in OxR cells, and its knockdown reduced cell viability, colony formation, and glycolytic activity while increasing apoptosis. m6A modification of CPSF6 mRNA was elevated in OxR cells, correlating with increased METTL3 expression. METTL3 knockdown decreased CPSF6 levels and m6A enrichment, enhancing mRNA degradation, while its overexpression stabilized CPSF6 mRNA, promoting resistance. Xenograft experiments showed that CPSF6 knockdown suppressed tumor growth and glycolysis. Thus, CPSF6 is identified as a mediator of oxaliplatin resistance in CRC, regulated by the METTL3/m6A axis, suggesting potential therapeutic targets to overcome resistance.

NUDT21 lactylation reprograms alternative polyadenylation to promote cuproptosis resistance

Alternative polyadenylation (APA) is critical for shaping transcriptome diversity and modulating cancer therapeutic resistance. While lactate is a well-established metabolic signal in cancer progression, its role in APA regulation remains unclear. Here, we demonstrate that L-lactate-induced lactylation of NUDT21 drives transcriptomic reprogramming through APA modulation. NUDT21 lactylation enhances its interaction with CPSF6, facilitating CFIm complex formation and inducing 3' untranslated region (UTR) lengthening of FDX1. Extension of the FDX1 3' UTR attenuates its protein output, thereby conferring resistance to cuproptosis in esophageal squamous cell carcinoma (ESCC). Furthermore, we identify AARS1 as the lactylation "writer" catalyzing NUDT21 K23 lactylation, and HDAC2 as its enzymatic "eraser". Clinically, elevated levels of both LDHA and NUDT21, as well as increased K23-lactylated NUDT21, are associated with reduced FDX1 expression and worse prognosis in ESCC patients. Notably, combined targeting of the lactate-NUDT21-FDX1-cuproptosis axis with the clinical LDHA inhibitor stiripentol and the copper ionophore elesclomol synergistically suppressed tumor growth. Collectively, our work identifies lactylated NUDT21 as a critical factor linking cellular metabolism to APA and proposes a promising therapeutic strategy for ESCC treatment.

KDELR3 is transcriptionally activated by FOXM1 and accelerates lung adenocarcinoma growth and metastasis via inhibiting endoplasmic reticulum stress-induced cell apoptosis

Lung cancer is still considered to be the leading cause of cancer-related death worldwide, and lung adenocarcinoma (LUAD) is the most common kind. KDEL Endoplasmic Reticulum Protein Retention Receptor 3 (KDELR3) is a critical regulator of the endoplasmic reticulum (ER) stress and the followed unfolded protein response (UPR) process, which are critical in tumor development. However, the role of KDELR3 in LUAD tumor progression remains poorly understood. In this work, we demonstrated that KDELR3 is significantly upregulated in LUAD tumor tissues and cell lines. Suppression of KDELR3 promoted the phosphorylation level of UPR-related pathways, PERK, and EIF2α in LUAD cell lines. The downregulation of KDELR3 promoted ER stress-induced cell apoptosis, decreased the protein expression of Bcl-2, and increased the protein expression of Bax in LUAD cells. Moreover, the knockdown of KDELR3 inhibits LUAD cell invasion. In vivo animal experiments confirmed that the inhibition of KDELR3 suppresses LUAD tumor growth and metastasis. Mechanistic studies showed that transcription factor FOXM1 may serve as an upstream factor of KDELR3. The upregulation of FOXM1 increased the transcriptional activity of KDELR3. Further results illustrated that FOXM1 directly binds to the promoter of KDELR3, thus upregulating its expression. Finally, rescue experiments demonstrated that FOXM1 inhibition-induced cell apoptosis and invasion could be reversed by KDELR3 overexpression. Overall, our findings indicated that KDELR3 is transcriptionally upregulated by FOXM1 and accelerates tumor growth and lung metastasis in LUAD by inhibiting ER stress-induced cell apoptosis.

TRAF3IP3 Induces ER Stress-Mediated Apoptosis with Protective Autophagy to Inhibit Lung Adenocarcinoma Proliferation

TNF receptor-associated factor 3 interacting protein 3 (TRAF3IP3/T3JAM) exhibits dual roles in cancer progression. While upregulated in most malignancies and critical for immune regulation. However, the specific effects and molecular mechanisms of TRAF3IP3 on the progression of lung adenocarcinoma (LUAD) remains poorly understood. This study reveals TRAF3IP3 is upregulated in several tumor tissues but exclusively decreased in LUAD and Lung squamous cell carcinoma (LUSC) tissues, consequential in a favorable overall survival (OS) in LUAD rather than LUSC. Herein, it is reported that TRAF3IP3 can suppress cell proliferation and promote the apoptosis rate of LUAD cells by inducing excessive ER stress-related apoptosis. Importantly, TRAF3IP3 triggers ER stress via the PERK/ATF4/CHOP pathway, accompanied by stimulated ER stress-induced cytoprotective autophagy in LUAD cells. Through IP-MS analysis, STRN3 is identified as a direct downstream interactor with TRAF3IP3 and corroborated to regulate ER stress positively. Mechanistically, TRAF3IP3 facilitates the recruitment of STRN3 to the ER lumen through its transmembrane domain and fulfills its functional role in ER stress in an STRN3-dependent manner in LUAD cells. Given its dual role in orchestrating ER stress-associated apoptosis and autophagy in LUAD cell fate determination, the importance of TRAF3IP3 is highlighted as novel therapeutic target for LUAD treatment.

Exosomes derived from umbilical cord blood NK cells inhibit the progression of pancreatic cancer by targeting ROS-mediated mitochondrial dysfunction

Emerging research indicates that natural killer (NK) cell-derived exosomes (NK-exo) play a significant role in cancer development. However, their regulatory mechanisms, particularly in pancreatic cancer, remain poorly elucidated. This study employed an in vitro co-culture system and an in vivo subcutaneous tumor model to evaluate the anti-tumor effect of NK-exo on pancreatic cancer. Umbilical cord blood (UCB)-derived NK-exo displayed characteristic exosomal morphology, size, and marker expression and was internalized by PANC- 1 cells. NK-exo significantly and dose-dependently reduce cell proliferation, migration, and invasion (P < 0.01). Further analysis demonstrated that NK-exo induced mitochondrial apoptosis in PANC- 1 cells by altering reactive oxygen species (ROS, P < 0.0001) and mitochondrial membrane potential (MPP) levels (P < 0.0001), effects that were significantly diminished with N-acetylcysteine (NAC) treatment (P < 0.0001). Furthermore, NK-exo treated PANC- 1 cells showed upregulation of the apoptotic markers Caspase3 (P < 0.0001) and Caspase9 (P = 0.0086) and reduced the release of PGC- 1α (P = 0.0064), TFAM (P < 0.0001), and SOD2 (P = 0.0021) as demonstrated by qRT-PCR. Western blot analyses revealed a dose dependent significant elevation of total Caspase3, Caspase9, Bax, and cytochrome c level and depression in the anti-apoptotic Bcl- 2. Animal experiments further confirmed that NK-exo treatment significantly reduced tumor volume and weight and increased Bax protein expression relative to the tumor model group. These findings indicate that NK-exo can enter PANC- 1 cells via endocytosis, induce mitochondrial oxidative damage, and suppress PANC- 1 cell progression, thereby demonstrating a robust anti-pancreatic cancer effect.

IGF2BP3 recruits NUDT21 to regulate SPTBN1 alternative polyadenylation and drive ovarian cancer progression

Ovarian cancer (OC) is one of the deadliest gynecological malignancies. As the prevalent post-transcriptional regulation, alternative polyadenylation (APA) plays a crucial role in various tumors. Here we identify that the APA regulator NUDT21 is upregulated in OC and promotes malignant progression. We further demonstrate that IGF2BP3 interacts with NUDT21, which suggests m6A modification could regulate APA processing. Mechanistically, IGF2BP3, recognizing the m6A-modified site in intron 32 of SPTBN1, recruits NUDT21 to promote the usage of the SPTBN1 proximal polyadenylation site (PAS), thus increasing the generation of short transcripts in OC cells. Intriguingly, the SPTBN1 long variant demonstrates tumor-suppressive properties, whereas the short variant enhances oncogenic activity in OC. Subsequently, we illustrate that the long isoform inhibits tumor growth and metastasis by binding to CDK1 and blocking the G2/M phase of the cell cycle. In conclusion, this study uncovers a previously unrecognized regulatory mechanism in OC, which could provide potential therapeutic strategies for OC.

Endoplasmic reticulum stress related super-enhancers suppress cuproptosis via glycolysis reprogramming in lung adenocarcinoma

The role of copper in tumor progression is thought to be a double-edged sword. Moderate levels of copper promote tumor progression, while excess copper induces a novel form of programmed cell death known as cuproptosis. However, the relationship between lung adenocarcinoma (LUAD) and cuproptosis remains poorly understood. Copper colorimetric assay identified the progression of LUAD simultaneous associated with higher copper accumulation. Single-cell RNA sequencing further identified the activation of unfolded protein response correlates with copper accumulation, particularly the spliced form of XBP1 (XBP1s). XBP1s negatively regulates the protein level of LIPT1 to inhibit LUAD cell death induced by copper-loaded ionophore elesclomol. CUT&Tag-seq and chromosome conformation capture (3 C) experiment showed that XBP1s affect the frequency of MGRN1 promoter-enhancer interactions in various copper environments by forming super-enhancers. Additionally, MGRN1 promotes the ubiquitination and degradation of LIPT1, which in turn supports glycolysis in LUAD cells. In mouse xenograft models, overexpression of XBP1s significantly inhibits the cuproptosis induced by copper ionophores. Co-administration with SEs inhibitor and copper ionophore also markedly reduced tumor volume and growth rate. Our study sheds light on the molecular mechanism by which XBP1s affect the cuproptosis through super-enhancers formation in LUAD and suggested the potential clinical value of copper ionophore as well as a potential biomarker XBP1s for treatment response.

CircGTF2H2C Regulates NLRP3 Dephosphorylation via Modulating PTPN11 Expression in Spinal Cord Injury

Pathological changes following spinal cord injury (SCI) are characterized by a gradual enlargement of the lesion area, often leading to cavity formation, accompanied by reactive astrocytic hyperplasia and chronic inflammation. Chronic inflammation tends to stimulate astrocyte activation and spinal cavity cavitation. Post-SCI inflammation primarily results from the activation of M1/M2 microglia, with M1 microglia inducing the death of reactive astrocytes in rats, thereby promoting inflammation. Additionally, the NLRP3 inflammasome is critically involved in the post-SCI inflammatory response, as its activation leads to the release of pro-inflammatory cytokines, further contributing to secondary injury and functional impairment. This study aimed to investigate the molecular mechanisms through which circular RNAs (circRNAs), influence the inflammatory response following spinal cord injury, particularly focusing on its role in modulating NLRP3 activation. Animal and cell models were established, and the success of the models and the secretion of factors were evaluated using the BBB locomotor rating scale, RT-qPCR, and WB. The circular structure of circGTF2H2C was verified through AGE, RNase R treatment, and actinomycin D treatment. Additionally, we investigated the interactions between circGTF2H2C and PTPN11, including the analysis of NLRP3 phosphorylation status through WB and Co-IP. Lastly, potential miRNA interactions with circGTF2H2C and PTPN11 were explored through RNA pull-down assays and luciferase reporter assays to confirm binding relationships. This study confirmed that circGTF2H2C was up-regulated in SCI tissues. Experimental results demonstrated that circGTF2H2C regulated the expression of pro-inflammatory factors IL-1β and IL-18. Further investigation revealed that circGTF2H2C played a pro-inflammatory role by regulating the phosphorylation level of NLRP3, while PTPN11 was also found to contribute to SCI induction. In addition, circGTF2H2C also affected SCI by competitively binding miR-1323 to up-regulate PTPN11. In summary, circGTF2H2C regulates NLRP3 dephosphorylation via PTPN11 in spinal cord injury, highlighting its potential as a target for therapeutic intervention.

PRKCSH enhances colorectal cancer radioresistance via IRE1α/XBP1s-mediated DNA repair

Neoadjuvant radiotherapy is the standard treatment for locally advanced rectal cancer, but resistance to this therapy remains a significant clinical challenge. Understanding the molecular mechanisms of radioresistance and developing strategies to enhance radiosensitivity are crucial for improving treatment outcomes. This study investigated the role of PRKCSH in colorectal cancer radioresistance and its underlying mechanisms. Our results demonstrate that PRKCSH is upregulated in colorectal cancer cells following ionizing radiation. Inhibiting PRKCSH sensitized these cells to radiation by reducing clonogenic survival, promoting apoptosis, and impairing DNA damage repair. Mechanistically, PRKCSH inhibition reduced p53 ubiquitination and degradation by activating the ER stress IRE1α/XBP1s pathway after radiation exposure, which enhanced DNA repair and contributed to radioresistance. In preclinical CRC models, PRKCSH depletion suppressed tumor growth and increased radiosensitivity. Similarly, in patient-derived organoid models, PRKCSH knockdown reduced organoid growth post-radiotherapy. In rectal cancer patients receiving neoadjuvant radiotherapy, higher PRKCSH expression in post-treatment samples correlated with reduced tumor regression. These findings suggest that targeting PRKCSH diminishes radioresistance by impairing DNA repair through the modulation of ER stress. Furthermore, PRKCSH expression may serve as a biomarker for evaluating radiotherapy efficacy and clinical outcomes in rectal cancer patients undergoing neoadjuvant therapy.

Mapping Dynamic Protein Clustering with AIEgen-Active Chemigenetic Probe

Protein clustering/disassembling is a fundamental process in biomolecular condensates, playing a crucial role in cell fate decision and cellular homeostasis. However, the inherent features of protein clustering, especially for its reversible behavior and subtle microenvironment variation, present significant hurdles in probe chemistry for tracking protein clustering dynamics. Herein, we report a bilateral-tailored chemigenetic probe, in which an "amphiphilic" aggregate-induced emission luminogen (AIEgen) QMSO3Cl is covalently conjugated to a protein tag that is genetically fused to protein-of-interest (POI). Prior to target POI, the "amphiphilic" AIE-active QMSO3Cl achieves a completely dark state in both aqueous biological environment and lipophilic organelles, thereby ensuring an ultra-low intrinsic background interference. Upon reaching POI, the combination of synthetic molecule and genetically encoded protein allows for protein clustering-dependent ultra-sensitive response, with a substantial lighting-up fluorescence (67.5-fold) as protein transitions from disassembling to clustering state. Such ultra-high signal-to-noise ratio enables to monitor the dynamic and fate of inositol requiring enzyme 1 (IRE1) clustering/disassembling under both acute and chronic endoplasmic reticulum (ER) stress in living cells. For the first time, we have demonstrated the use of chemigenetic probe to reveal therapy-induced ER stress and screen drugs in a three-dimensional scenario: microviscosity change, clustering dynamic, and cluster morphology. This chemigenetic probe design strategy would greatly facilitate the advancement of mapping protein dynamics in cell homeostasis and medicine research.

Roles of LncRNA ARSR in tumor proliferation, drug resistance, and lipid and cholesterol metabolism

Cancer is one of the most serious diseases that threaten human life and health. Among all kinds of diseases, the mortality rate of malignant tumors is the second highest, second only to cardio-cerebrovascular diseases. Cancer treatment typically involves imaging, surgery, and pathological analysis. When patients are identified as carcinoma by the above means, there are often problems of distant metastasis, delayed treatment, and drug tolerance, indicating that patients have some poor prognosis and overall survival. Hence, the development of novel molecular biomarkers is of great clinical importance. In recent years, as an important mediator of material and information exchange between cells in the tumor microenvironment, lncRNA have attracted widespread attention for their roles in tumor development. In this review, we comprehensively summarize the up-to-date knowledge of lncARSR on diverse cancer types which mainly focuses on tumor proliferation, drug tolerance, and lipid and cholesterol metabolism, highlighting the potential of lncARSR as a diagnostic and prognostic biomarker and even a therapeutic target. In our final analysis, we provide a synthesized overview of the directions for future inquiry into lncARSR, and we are eager to witness the advancement of research that will elucidate the multifaceted nature of this lncRNA.

WDR62 mediates MAPK/ERK pathway to stimulate DNA damage repair and attenuate cisplatin sensitivity in lung adenocarcinoma

Chemotherapy resistance has long stood in the way of therapeutic advancement for lung cancer patients, the malignant tumor with the highest incidence and fatality rate in the world. Patients with lung adenocarcinoma (LUAD) now have a dismal prognosis due to the development of cisplatin (DDP) resistance, forcing them to use more costly second-line therapies. Therefore, overcoming resistance and enhancing patient outcomes can be achieved by comprehending the regulatory mechanisms of DDP resistance in LUAD. WD repeat domain 62 (WDR62) expression in LUAD tissues and in DDP-resistant or sensitive LUAD patients was analyzed bioinformatically, and a K-M plot was utilized to assess survival status. Real-time quantitative PCR was employed for WDR62 expression detection, cell-counting kit-8 assay for half maximal inhibitory concentration determination, flow cytometry for cell apoptosis detection, immunofluorescence for γ-H2AX expression analysis, and western blot for nonhomologous end joining repair and mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathway-related protein expression analysis. Poor prognosis was linked to WDR62, which was overexpressed in LUAD tissues and cells. Compared to sensitive cells, DDP-resistant cells had increased WDR62 expression. WDR62 knockdown may enhance DDP-induced cell apoptosis while reducing cell proliferation and DNA damage repair. Functional investigations verified that overexpressed WDR62's encouraging impact on DNA damage repair in A549/DDP cells could be reversed by MAPK inhibitors, increasing the cells' susceptibility to DDP. LUAD cells became less sensitive to DDP when WDR62 activated the MAPK/ERK pathway, which promoted DNA damage repair, indicating that DDP resistance might be reversed by treating LUAD with inhibitors of the MAPK pathway.

Tanreqing suppresses the proliferation and migration of non-small cell lung cancer cells by mediating the inactivation of the HIF1α signaling pathway via exosomal circ-WDR78

Circular RNAs (circRNAs) have emerged as regulators of cancer progression, including non-small cell lung cancer (NSCLC). Tanreqing (TRQ), a traditional Chinese medicine, is used clinically for respiratory diseases. RT-qPCR quantified circ-WDR78 expression in NSCLC cells. Cell growth, apoptosis, invasion, and migration were assessed by functional assays. RNA-binding protein immunoprecipitation (RIP), luciferase reporter, and RNA pull-down assays determined the competing endogenous RNA (ceRNA) network of circ-WDR78. The interaction between HIF1α and CD274 (PD-L1) promoter was analyzed by chromatin immunoprecipitation (ChIP). Circ-WDR78 expression was up-regulated in TRQ-treated NSCLC cells. Functionally, circ-WDR78 exhibited anti-tumor effects in these cells. Additionally, circ-WDR78 could also induce reactive oxygen species (ROS) accumulation by down-regulating HIF1α expression, promoting autophagy. Mechanistically, circ-WDR78 destabilizes HIF1α via the miR-1265/FBXW8 axis. TRQ-induced exosome secretion from NSCLC cells inhibits PD-L1 expression, preventing immune escape. We found that TRQ-treated NSCLC cells secrete exosomes to transmit circ-WDR78 to untreated NSCLC cells, inhibiting the malignancy of recipient tumor cells. In conclusion, TRQ inhibits NSCLC cell proliferation, invasion, and migration through exosomal circ-WDR78-mediated inactivation of the HIF1α signaling pathway, providing potential insight into TRQ injection for NSCLC treatment.

Jianpi Yangzheng Xiaozheng granule induced ferroptosis to suppress gastric cancer progression through reprogramming lipid metabolism via SCD1/Wnt/β-catenin axis

The incidence of Poorly cohesive carcinoma (PCC) has steadily risen in recent years, posing a significant clinical challenge. To reveal the anti-tumor effects of Jianpi Yangzheng Xiaozheng granule (JPYZXZ) in PCC, an initial investigation was performed using CCK-8, colony formation, scratch, and transwell assays. This was followed by network pharmacology studies to gain a deeper understanding of JPYZXZ's impact on gastric cancer (GC). Then reactive oxygen species (ROS), Fe2+, malondialdehyde (MDA), glutathione (GSH), Oil Red O staining, BODIPY493/503, triglyceride (TG), and cholesterol (TC) assay kits and western blot (Wb) analysis were applied to exam the regulatory effects of JPYZXZ on ferroptosis and lipid metabolism. Additionally, molecular docking studies and Wb analysis were used to further investigate the mechanisms of JPYZXZ on PCC. Finally, in vivo animal studies were conducted. The results show that JPYZXZ can inhibit the proliferation and migration of PCC cell. It increases the levels of ROS, Fe2+, MDA, while declining the content of GSH, TC, TG, and lipid droplet accumulation within cellular compartments. Wb indicates that JPYZXZ can negatively regulate the expression of proteins, including glutathione peroxidase 4 (GPX4), cystine/glutamate antipoter SLC7A11 (xCT), fatty acid synthase (FASN), and acetyl coenzyme A carboxylase 1 (ACC1). Furthermore, ferrostatin-1 (fer-1) is able to reverse the effects of JPYZXZ on the aforementioned markers of ferroptosis and lipid metabolism. Molecular docking analyses reveal that JPYZXZ exhibits a favorable binding affinity towards Stearoyl-Coenzyme A desaturase 1 (SCD1). Mechanism studies demonstrate that JPYZXZ is capable of down-regulating the expressions of proteins like SCD1, β-catenin, GPX4, and xCT, which is analogous to the effects of SCD1 knockdown and the application of SCD1 inhibitor A939572. Nevertheless, when SCD1 is knocked down, JPYZXZ is unable to further downregulate the expressions of these proteins. Animal studies have corroborated the in vitro tumor-inhibiting effects of JPYZXZ. Therefore, this study offers the first evidence that JPYZXZ inhibits PCC progression by orchestrating ferroptosis and altering lipid metabolism, mediated by the SCD1/Wnt/β-catenin pathway.

Alternative polyadenylation in cancer: Molecular mechanisms and clinical application

Alternative polyadenylation (APA) serves as a crucial mechanism for the posttranscriptional regulation of gene expression and influences gene expression by generating diverse mRNA isoforms. This process is regulated by a diverse array of RNA-binding proteins (RBPs), which selectively bind to specific sequences or structures within the pre-mRNA molecule. Dysregulation of APA and its associated RBPs has been implicated in numerous diseases, including cardiovascular diseases, nervous system disease, and cancer. For instance, aberrant APA events have been observed in several types of tumors, contributing to tumor heterogeneity and affecting key cellular pathways involved in cell proliferation, invasion, metastasis, and response to therapy. This review critically evaluates the current understanding of APA mechanisms and the multifaceted roles of RBPs in orchestrating this intricate process. We highlight recent advancements in high-throughput sequencing and bioinformatics tools that have enhanced our ability to study APA on a genome-wide scale. Moreover, we explored the pathological consequences of APA dysregulation, emphasizing its role in oncogenesis. By elucidating the intricate relationships between APA and RBPs, this review aims to underscore the potential of targeting the APA machinery and RBPs for therapeutic intervention. Understanding these molecular processes holds promise for developing novel diagnostic markers and treatment strategies for a range of human cancers.

Advancements and challenges of R-loops in cancers: Biological insights and future directions

R-loops involve in various biological processes under human normal physiological conditions. Disruption of R-loops can lead to disease onset and affect the progression of illnesses, particularly in cancers. Herein, we summarized and discussed the regulative networks, phenotypes and future directions of R-loops in cancers. In this review, we highlighted the following insights: (1) R-loops significantly influence cancer development, progression and treatment efficiency by regulating key genes, such as PARPs, BRCA1/2, sex hormone receptors, DHX9, and TOP1. (2) Currently, the ATM, ATR, cGAS/STING, and noncanonical pathways are the main pathways that involve in the regulatory network of R-loops in cancer. (3) Cancer biology can be modulated by R-loops-regulated phenotypes, including RNA methylation, DNA and histone methylation, oxidative stress, immune and inflammation regulation, and senescence. (4) Regulation of R-loops induces kinds of drug resistance in various cancers, suggesting that targeting R-loops maybe a promising way to overcome treatment resistance. (5) The role of R-loops in tumorigenesis remains controversial, and senescence may be a crucial research direction to unravel the mechanism of R-loop-induced tumorigenesis. Looking forward, further studies are needed to elucidate the specific mechanisms of R-loops in cancer, laying the groundwork for preclinical and clinical research.

Silencing HEATR1 Rescues Cisplatin Resistance of Non-small Cell Lung Cancer by Inducing Ferroptosis via the p53/SAT1/ALOX15 Axis

BACKGROUND

Cisplatin (DDP) is a commonly used chemotherapy agent. However, its resistance to the drug is a major challenge in its clinical application. Earlier research has suggested a connection between HEATR1 and chemoresistance in cancer. However, additional investigation is needed to better understand its involvement in resistance to DDP. In this study, we aimed to determine the regulatory effect of HEATR1 on the resistance of cisplatin in NSCLC.

METHODS

We collected specimens of both DDP-resistant and non-resistant NSCLC to examine the expression of HEATR1. Additionally, we established cisplatin-resistant cells of NSCLC using the A549 cell line. Cell ability was examined by CCK-8 assay. Cell apoptosis and lipid ROS were examined by flow cytometry. The expressions of HEATR1, p53, SAT1, and ALOX15 were determined by qRT-PCR and Western blot. The tumor xenograft experiment was conducted to assess the impact of silencing HEATR1 on cisplatin resistance in vivo in NSCLC.

RESULTS

The expression levels of HEATR1 were found to be significantly elevated in DDP-resistant tissues and cells of NSCLC as compared to non-resistant counterparts. Conversely, the expression levels of p53, SAT1, and ALOX15 were observed to be reduced in DDP-resistant cells. Through the inhibition of HEATR1, the proliferation of DDP-resistant cells was significantly suppressed, while the generation of lipid ROS was enhanced. This effect was achieved by activating ferroptosis and the p53/SAT1/ALOX15 pathway, as demonstrated both in vitro and in vivo. Conversely, the overexpression of HEATR1 exhibited opposite effects. Furthermore, the silencing of p53 and ALOX15 reversed the oncogenic effects of HEATR1 and inhibited ferroptosis in DDP-resistant NSCLC cells, suggesting the involvement of p53 and ALOX15 in HEATR1-mediated DDP resistance.

CONCLUSION

Finally, the findings revealed that HEATR1 silencing reduced DDP resistance in NSCLC by inducing ferroptosis via the p53/SAT1/ALOX15 axis. HEATR1 might become a potential target for overcoming DDP resistance in NSCLC treatment.

Lingguizhugan decoction alleviates gestational diabetes mellitus by modulating the PI3K-AKT pathway and oxidative stress: Network pharmacology and experimental evidence

The Lingguizhugan decoction (LGZGD) is a promising traditional Chinese medicine for the treatment of gestational diabetes mellitus (GDM). However, its bioactive compounds and therapeutic mechanisms remain unknown. The main chemical composition of LGZGD was analyzed by high-performance liquid chromatography-mass spectrometry (HPLC-MS). Furthermore, the underlying mechanisms of LGZGD against GDM were elucidated through network pharmacology and molecular docking. The therapeutic efficacy and targets of LGZGD were further confirmed via an in vitro GDM model (high glucose [HG]-treated HTR-8/SVneo cells). Four compounds of LGZGD, namely, cinnamaldehyde, glycyrrhizic acid, 2-atractylenolide, and pachymic acid, were detected. A total of 26 targets for LGZGD treating GDM were obtained, which were mainly involved in oxidative stress and the PI3K-AKT signaling pathway. The protein-protein interaction (PPI) network unveiled that AKT1, TLR4, TP53, and NOS3 were hub therapeutic targets. Molecular docking showed that these targets had strong affinity with key compounds. In vitro experiments confirmed that LGZGD treatment promoted HG-induced cell viability, migration, and invasion ability while inhibited the apoptosis rate and oxidative stress. Mechanically, western blot revealed that LGZGD may protect HG-treated cells by activating the PI3K-AKT pathway and suppressing TLR4 expression. Our study preliminarily explored the mechanism of LGZGD in GDM treatment, providing a scientific basis for the clinical application of LGZGD.

Hydrazone copper(II) complexes suppressed lung adenocarcinoma by activating multiple anticancer pathway

Activating multiple anti-cancer pathways has great potential for tumor treatment. Herein, we synthesized two binuclear Cu(II) hydrazone complexes ([Cu2(HL1)2Cl2] 1 and [Cu2(HL1)2Br2] 2) and two mononuclear hydrazone-Cu(II) complexes ([Cu(HL2)Cl]·CH3OH 3 and [Cu(HL2)(H2O)Br]·2H2O 4), to evaluate their anti-lung cancer activities. MTT assays revealed that the Cu(II) complexes demonstrate superior anticancer activity compared to cisplatin. Among them, complex 3 exhibited selective toxicity towards A549 cancer cells in comparison to normal cells and demonstrated hemolytic activity comparable to cisplatin. The low toxicity and effective antitumor capabilities of complex 3 have been confirmed in xenograft experiments using A549 tumor-bearing mice. Interestingly, complex 3 eradicates lung tumor cells both in vivo and in vitro by initiating multiple anticancer pathways, including cuproptosis. Our research extends the study of hydrazone copper complexes and provides strategies for the treatment of lung cancer.

Overcoming cancer drug-resistance calls for novel strategies targeting abnormal alternative splicing

Abnormal gene alternative splicing (AS) events are strongly associated with cancer progression. Here, we summarize AS events that contribute to the development of drug resistance and classify them into three categories: alternative cis-splicing (ACS), alternative trans-splicing (ATS), and alternative back-splicing (ABS). The regulatory mechanisms underlying AS processes through cis-acting regulatory elements and trans-acting factors are comprehensively described, and the distinct functions of spliced variants, including linear spliced variants derived from ACS, chimeric spliced variants arising from ATS, and circRNAs generated through ABS, are discussed. The identification of dysregulated spliced variants, which contribute to drug resistance and hinder effective cancer treatment, suggests that abnormal AS processes may together serve as a precise regulatory mechanism enabling drug-resistant cancer cell survival or, alternatively, represent an evolutionary pathway for cancer cells to adapt to changes in the external environment. Moreover, this review summarizes recent advancements in treatment approaches targeting AS-associated drug resistance, focusing on cis-acting regulatory elements, trans-acting factors, and specific spliced variants. Collectively, gaining an in-depth understanding of the mechanisms underlying aberrant alternative splicing events and developing strategies to target this process hold great promise for overcoming cancer drug resistance.

Novel SERCA2 inhibitor Diphyllin displays anti-tumor effect in non-small cell lung cancer by promoting endoplasmic reticulum stress and mitochondrial dysfunction

Abnormal calcium signaling is associated with non-small cell lung cancer (NSCLC) malignant progression, poor survival and chemotherapy resistance. Targeting endoplasmic reticulum (ER) Ca2+ channels or pumps to block calcium uptake in the ER induces ER stress and concomitantly promotes mitochondrial calcium uptake, leading to mitochondrial dysfunction and ultimately inducing cell death. Here, we identified Diphyllin was a potential specific inhibitor of endoplasmic reticulum (ER) calcium-importing protein sarco/endoplasmic-reticulum Ca2+ ATPase 2 (SERCA2). In vitro and in vivo studies showed that Diphyllin increased NSCLC cell apoptosis, along with inhibition of cell proliferation and migration. Mechanistically, Diphyllin promoted ER stress by directly inhibiting SERCA2 activity and decreasing ER Ca2+ levels. At the same time, the accumulated Ca2+ in cytoplasm flowed into mitochondria to increase reactive oxygen species (ROS) and decrease mitochondrial membrane potential (MMP), leading to cytochrome C (Cyto C) release and mitochondrial dysfunction. In addition, we found that Diphyllin combined with cisplatin could have a synergistic anti-tumor effect in vitro and in vivo. Taken together, our results suggested that Diphyllin, as a potential novel inhibitor of SERCA2, exerts anti-tumor effects by blocking ER Ca2+ uptake and thereby promoting ER stress and mitochondrial dysfunction.

Crosstalk among Alternative Polyadenylation, Genetic Variants and Ubiquitin Modification Contribute to Lung Adenocarcinoma Risk

Ubiquitin modification and alternative polyadenylation play crucial roles in the onset and progression of cancer. Hence, this study aims to comprehensively and deeply understand gene regulation and associated biological processes in lung adenocarcinoma (LUAD) by integrating both mechanisms. Alternative polyadenylation (APA)-related E3 ubiquitin ligases in LUAD were identified through multiple databases, and the association between selected genetic loci influencing gene expression (apaQTL-SNPs) and LUAD risk were evaluated through the GWAS database of the Female Lung Cancer Consortium in Asia (FLCCA). Subsequently, the interaction between RNF213 and ZBTB20, as well as their functional mechanisms in LUAD, were investigated using bioinformatics analysis, Western blot, co-immunoprecipitation, and colony formation experiments. A total of five apaQTL-SNPs (rs41301932, rs4494603, rs9890400, rs56066320, and rs41301932), located on RNF213, were significantly associated with LUAD risk (p < 0.05), and they inhibit tumor growth through ubiquitin-mediated degradation of ZBTB20.

Endoplasmic reticulum stress and quality control in relation to cisplatin resistance in tumor cells

The endoplasmic reticulum (ER) is a crucial organelle that orchestrates key cellular functions like protein folding and lipid biosynthesis. However, it is highly sensitive to disturbances that lead to ER stress. In response, the unfolded protein response (UPR) activates to restore ER homeostasis, primarily through three sensors: IRE1, ATF6, and PERK. ERAD and autophagy are crucial in mitigating ER stress, yet their dysregulation can lead to the accumulation of misfolded proteins. Cisplatin, a commonly used chemotherapy drug, induces ER stress in tumor cells, activating complex signaling pathways. Resistance to cisplatin stems from reduced drug accumulation, activation of DNA repair, and anti-apoptotic mechanisms. Notably, cisplatin-induced ER stress can dualistically affect tumor cells, promoting either survival or apoptosis, depending on the context. ERAD is crucial for degrading misfolded proteins, whereas autophagy can protect cells from apoptosis or enhance ER stress-induced apoptosis. The complex interaction between ER stress, cisplatin resistance, ERAD, and autophagy opens new avenues for cancer treatment. Understanding these processes could lead to innovative strategies that overcome chemoresistance, potentially improving outcomes of cisplatin-based cancer treatments. This comprehensive review provides a multifaceted perspective on the complex mechanisms of ER stress, cisplatin resistance, and their implications in cancer therapy.

A novel microRNA miR-4433a-3p as a potential diagnostic biomarker for lung adenocarcinoma

Background

Lung adenocarcinoma is one of the leading causes of cancer-related deaths because of the lack of early specific clinical indicators. MicroRNAs (miRNAs) have become the focus in lung cancer diagnosis. Further studies are required to explore miRNA expression in the serum of lung adenocarcinoma patients and their correlation with therapy and analyse specific messenger RNA targets to improve the specificity and sensitivity of early diagnosis.

Methods

The Toray 3D-Gene miRNA array was used to compare the expression levels of various miRNAs in the sera of patients with lung adenocarcinoma and healthy volunteers. Highly expressed miRNAs were selected for further analysis. To verify the screening results, serum and pleural fluid samples were analysed using qRT-PCR. Serum levels of the miRNAs and their correlation with the clinical information of patients with lung adenocarcinoma were analysed. The functions of miRNAs were further analysed using the Kyoto Encyclopedia of Gene and Genomes and Gene Ontology databases.

Results

Microarray analysis identified 60 and 50 miRNAs with upregulated and downregulated expressions, respectively, in the serum of patients with lung adenocarcinoma compared to those in healthy individuals. Using qRT-qPCR to detection of miRNAs expression in the serum or pleural effusion of patients with early and advanced lung adenocarcinoma, we found that miR-4433a-3p could be used as a diagnostic marker and therapeutic evaluation indicator for lung adenocarcinoma. Serum of miR-4433a-3p levels significantly correlated with the clinical stage. miR-4433a-3p may be more suitable than other tumour markers for the early diagnosis and evaluation of therapeutic effects in lung adenocarcinoma. miR-4433a-3p may affect tumour growth and metastasis by acting on target genes (PIK3CD, UBE2J2, ICMT, PRDM16 and others) and regulating tumour-related signalling pathways (MAPK signal pathway, Ras signalling pathway and others).

Conclusion

miR-4433a-3p may serve as a biomarker for the early diagnosis of lung adenocarcinoma and monitoring of therapeutic effects.

Autophagy-driven regulation of cisplatin response in human cancers: Exploring molecular and cell death dynamics

Despite the challenges posed by drug resistance and side effects, chemotherapy remains a pivotal strategy in cancer treatment. A key issue in this context is macroautophagy (commonly known as autophagy), a dysregulated cell death mechanism often observed during chemotherapy. Autophagy plays a cytoprotective role by maintaining cellular homeostasis and recycling organelles, and emerging evidence points to its significant role in promoting cancer progression. Cisplatin, a DNA-intercalating agent known for inducing cell death and cell cycle arrest, often encounters resistance in chemotherapy treatments. Recent studies have shown that autophagy can contribute to cisplatin resistance or insensitivity in tumor cells through various mechanisms. This resistance can be mediated by protective autophagy, which suppresses apoptosis. Additionally, autophagy-related changes in tumor cell metastasis, particularly the induction of Epithelial-Mesenchymal Transition (EMT), can also lead to cisplatin resistance. Nevertheless, pharmacological strategies targeting the regulation of autophagy and apoptosis offer promising avenues to enhance cisplatin sensitivity in cancer therapy. Notably, numerous non-coding RNAs have been identified as regulators of autophagy in the context of cisplatin chemotherapy. Thus, therapeutic targeting of autophagy or its associated pathways holds potential for restoring cisplatin sensitivity, highlighting an important direction for future clinical research.

Activation of the PI3K/AKT signaling pathway by ARNTL2 enhances cellular glycolysis and sensitizes pancreatic adenocarcinoma to erlotinib

BACKGROUND

Pancreatic adenocarcinoma (PC) is an aggressive malignancy with limited treatment options. The poor prognosis primarily stems from late-stage diagnosis and when the disease has become therapeutically challenging. There is an urgent need to identify specific biomarkers for cancer subtyping and early detection to enhance both morbidity and mortality outcomes. The addition of the EGFR tyrosine kinase inhibitor (TKI), erlotinib, to gemcitabine chemotherapy for the first-line treatment of patients with advanced pancreatic cancer slightly improved outcomes. However, restricted clinical benefits may be linked to the absence of well-characterized criteria for stratification and dependable biomarkers for the prediction of treatment effectiveness.

METHODS AND RESULTS

We examined the levels of various cancer hallmarks and identified glycolysis as the primary risk factor for overall survival in PC. Subsequently, we developed a glycolysis-related score (GRS) model to accurately distinguish PC patients with high GRS. Through in silico screening of 4398 compounds, we discovered that erlotinib had the strongest therapeutic benefits for high-GRS PC patients. Furthermore, we identified ARNTL2 as a novel prognostic biomarker and a predictive factor for erlotinib treatment responsiveness in patients with PC. Inhibition of ARNTL2 expression reduced the therapeutic efficacy, whereas increased expression of ARNTL2 improved PC cell sensitivity to erlotinib. Validation in vivo using patient-derived xenografts (PDX-PC) with varying ARNTL2 expression levels demonstrated that erlotinib monotherapy effectively halted tumor progression in PDX-PC models with high ARNTL2 expression. In contrast, PDX-PC models lacking ARNTL2 did not respond favorably to erlotinib treatment. Mechanistically, we demonstrated that the ARNTL2/E2F1 axis-mediated cellular glycolysis sensitizes PC cells to erlotinib treatment by activating the PI3K/AKT signaling pathway.

CONCLUSIONS

Our investigations have identified ARNTL2 as a novel prognostic biomarker and predictive indicator of sensitivity. These results will help to identify erlotinib-responsive cases of PC and improve treatment outcomes. These findings contribute to the advancement of precision oncology, enabling more accurate and targeted therapeutic interventions.

Deciphering the immune modulation through deep transcriptomic profiling and therapeutic implications of DNA damage repair pattern in hepatocellular carcinoma

AIMS

DNA damage repair (DDR) plays a pivotal role in hepatocellular carcinoma (HCC), driving oncogenesis, progression, and therapeutic response. However, the mechanisms of DDR mediated immune cells and immuno-modulatory pathways in HCC are yet ill-defined.

METHODS

Our study introduces an innovative deep machine learning framework for precise DDR assessment, utilizing single-cell RNA sequencing (scRNA-seq) and bulk RNA-seq data. Single-cell RNA sequencing data were obtained and in total 85,628 cells of primary or post-immunotherapy cases were analyzed. Large-scale HCC datasets, including 1027 patients in house together with public datasets, were used for 101 machine-learning models and a novel DDR feature was derived at single-cell resolution (DDRscore). Druggable targets were predicted using the reverse phase protein array (RPPA) proteomic profiling of 169 HCC patients and RNA-seq data from 22 liver cancer cell lines.

RESULTS

Our investigation reveals a dynamic interplay of DDR with natural killer cells and B cells in the primary HCC microenvironment, shaping a tumor-promoting immune milieu through metabolic programming. Analysis of HCC post-immunotherapy demonstrates elevated DDR levels that induces epithelial-mesenchymal transition and fibroblast-like transformation, reshaping the fibrotic tumor microenvironment. Conversely, attenuated DDR promotes antigen cross-presentation by dendritic cells and CD8+ T cells, modulating the inflammatory tumor microenvironment. Regulatory network analysis identifies the CXCL10-CXCR3 axis as a key determinant of immunotherapeutic response in low DDR HCC, potentially regulated by transcription factors GATA3, REL, and TBX21. Using machine learning techniques by combining bulk RNA-seq data in house together with public datasets, we introduce DDRscore, a robust consensus DDR scoring system to predict overall survival and resistance to PD-1 therapy in HCC patients. Finally, we identify BRAF as a potential therapeutic target for high DDRscore patients.

CONCLUSION

Our comprehensive findings advance our understanding of DDR and the tumor microenvironment in HCC, providing insights into immune regulatory mechanisms mediated via DDR pathways.

Luteolin Protects Against 6-Hydoroxydopamine-Induced Cell Death via an Upregulation of HRD1 and SEL1L

Parkinson's Disease (PD) is caused by many factors and endoplasmic reticulum (ER) stress is considered as one of the responsible factors for it. ER stress induces the activation of the ubiquitin-proteasome system to degrade unfolded proteins and suppress cell death. The ubiquitin ligase 3-hydroxy-3-methylglutaryl-coenzyme A reductase degradation 1 (HRD1) and its stabilizing molecule, the suppressor/enhancer lin-12-like (SEL1L), can suppress the ER stress via the ubiquitin-proteasome system, and that HRD1 can also suppress cell death in familial and nonfamilial PD models. These findings indicate that HRD1 and SEL1L might be key proteins for the treatment of PD. Our study aimed to identify the compounds with the effects of upregulating the HRD1 expression and suppressing neuronal cell death in a 6-hydroxydopamine (6-OHDA)-induced cellular PD model. Our screening by the Drug Gene Budger, a drug repositioning tool, identified luteolin as a candidate compound for the desired modulation of the HRD1 expression. Subsequently, we confirmed that low concentrations of luteolin did not show cytotoxicity in SH-SY5Y cells, and used these low concentrations in the subsequent experiments. Next, we demonsrated that luteolin increased HRD1 and SEL1L mRNA levels and protein expressions. Furthermore, luteolin inhibited 6-OHDA-induced cell death and suppressed ER stress response caused by exposure to 6-OHDA. Finally, luteolin did not reppress 6-OHDA-induced cell death when expression of HRD1 or SEL1L was suppressed by RNA interference. These findings suggest that luteolin might be a novel therapeutic agent for PD due to its ability to suppress ER stress through the activation of HRD1 and SEL1L.

SEC23A confers ER stress resistance in gastric cancer by forming the ER stress-SEC23A-autophagy negative feedback loop

BACKGROUND

Sec23 homolog A (SEC23A), a core component of coat protein complex II (COPII), has been reported to be involved in several cancers. However, the role of SEC23A in gastric cancer remains unclear.

METHODS

The expression of SEC23A in gastric cancer was analyzed by using qRT-PCR, western blotting and IHC staining. The role of SEC23A in ER stress resistance was explored by functional experiments in vitro and vivo. The occupation of STAT3 on the SEC23A promoter region was verified by luciferase reporter plasmids and CHIP assay. The interaction between SEC23A and ANXA2 was identified by Co-IP and mass spectrometry analysis.

RESULTS

We demonstrated that SEC23A was upregulated in gastric cancer and predicted poor prognosis in patients with gastric cancer. Mechanistically, SEC23A was transcriptional upregulated by ER stress-induced pY705-STAT3. Highly expressed SEC23A promoted autophagy by regulating the cellular localization of ANXA2. The SEC23A-ANXA2-autophay axis, in turn, protected gastric cancer cells from ER stress-induced apoptosis. Furthermore, we identified SEC23A attenuated 5-FU therapeutic effectiveness in gastric cancer cells through autophagy-mediated ER stress relief.

CONCLUSION

We reveal an ER stress-SEC23A-autophagy negative feedback loop that enhances the ability of gastric cancer cells to resist the adverse survival environments. These results identify SEC23A as a promising molecular target for potential therapeutic intervention and prognostic prediction in patients with gastric cancer.

Untapping the Potential of Astragaloside IV in the Battle Against Respiratory Diseases

Respiratory diseases are an emerging public health concern, that pose a risk to the global community. There, it is essential to establish effective treatments to reduce the global burden of respiratory diseases. Astragaloside IV (AS-IV) is a natural saponin isolated from Radix astragali (Huangqi in Chinese) used for thousands of years in Chinese medicine. This compound has become increasingly popular due to its potential anti-inflammatory, antioxidant, and anticancer properties. In the last decade, accumulated evidence has indicated the AS-IV protective effect against respiratory diseases. This article presents a current understanding of AS-IV roles and mechanisms in combatting respiratory diseases. The ability of the agent to suppress oxidative stress, cell proliferation, and epithelial-mesenchymal transition (EMT), to attenuate inflammatory responses, and modulate programmed cell death (PCD) will be discussed. This review highlights the current challenges in respiratory diseases and recommendations to improve disease management.