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.

Rheumatoid arthritis (RA) is a chronic inflammatory polyarthritis leading to irreversible damage to the joints. The roots of Litsea cubeba (Lour.) Pers. (Family Lauraceae) has long been used as Dai Ethnopharmacy folk remedies for rheumatism. Our previous research found that LCA, a new type of dibenzyl butane lignin compound from L. cubeba, inhibited RANKL-induced osteoclast differentiation by suppressing Akt and MAPK pathways. This study aims to evaluate the anti-arthritic effects of LCA and its synthetic analogue (LCA1), as well as the underlying mechanism. In vitro anti-arthritic effects of LCA and LCA1 were evaluated in TNF-α-stimulated fibroblast-like synoviocytes (FLSs) by measuring cell proliferation and the expression of inflammatory factors with MTT assay, flow cytometry and ELISA. Western blotting was used to investigate the mechanism. Additionally, in vivo anti-arthritic effects of the dibenzylbutane lignans were detected in carrageenan-induced air pouch inflammation model in mice and adjuvant-induced arthritis (AIA) in rats. Results showed that both LCA and LCA1 suppressed inflammatory factors in the air pouch model. LCA markedly suppressed the inflammation, weight loss, and bone erosion in AIA rats. These data suggested that LCA and LCA1 may have therapeutic benefits in RA through regulation of apoptosis and inflammation in vitro and in vivo.

Purpose: Erythrocytes and fibroblasts in the pancreatic cancer tumor microenvironment promote tumor cell growth and invasion by providing nutrients and promoting immunosuppression. Additionally, they form a barrier against the penetration of chemotherapeutic drugs. Therefore, the search for diversified tumor-targeting materials plays an essential role in solving the above problems. Methods: Physicochemical characterization of Graphene fluorescent nanoparticles (GFNPs) and nanomedicines were analyzed by transmission electron microscopy (TEM), elemental analyzers and ultraviolet fluorescence (UV/FL) spectrophotometer. Localization of GFNPs in cell and tissue sections imaged with laser confocal microscope, fluorescence scanner and small animal in vivo imager. Qualitative detection and quantitative detection of GFNPs and GFNPs-GEM were performed using High performance liquid Results: Based on the 3 nm average dimensions, GFNPs penetrate vascular endothelial cells and smooth muscle cells, achieve up to label 30% tumor cells and 60% cancer-associated fibroblasts (CAFs) cells, and accurately label mature red blood cells in the tumor microenvironment. In orthotopic transplanted pancreatic cancer models, the fluorescence intensity of GFNPs in tumors showed a positive correlation with the cycle size of tumor development. The differential spatial distribution of GFNPs in three typical clinical pancreatic cancer samples demonstrated their diagnostic potential. To mediate the excellent targeting properties of GFNPs, we synthesized a series of nanomedicines using popular chemotherapeutic drugs, in which complex of GFNPs and gemcitabine (GFNPsGEM) possessed stability in vivo and exhibited effective reduction of tumor volume and fewer side effects. Conclusion: GFNPs with multiple targeting tumor microenvironments in pancreatic cancer possess diagnostic efficiency and therapeutic potential.

Many current microRNA (miRNA) expression datasets for renal cell carcinoma (RCC) often show inconsistent analysis results, so a shift to comprehensive analysis of multiple datasets can effectively accelerate molecular screening for precision medicine and translational medicine research. MicroRNA (miR)-188-5p is a clinically noteworthy miRNA whose aberrant expression was previously observed in a variety of cancers, but its role in RCC is unclear. In this study, we undertook a comprehensive analysis of four RCC miRNA expression datasets and validated the results using The Cancer Genome Atlas (TCGA) dataset and a cohort of collected clinical samples. Fifteen miRNAs were identified as potential diagnostic markers by the analysis of four RCC miRNAs datasets. Analysis of the TCGA kidney renal clear cell carcinoma dataset showed significantly shorter survival in RCC patients with reduced miR-188-5p expression levels, and our collection of RCC clinical samples showed low miR-188-5p expression in the tumors. Overexpression of miR-188-5p in Caki-1 and 786-O cells inhibited cell growth, colony formation, invasion, and migration. In contrast, miR-188-5p inhibitors reversed these cell phenotypes. We identified a binding site for miR-188-5p in the 3'-UTR region of myristoylated alanine-rich C-kinase substrate (MARCKS) mRNA and demonstrated an interaction between these two molecules. Quantitative RT-PCR and western blot analysis revealed that miR-188-5p could regulate the AKT/mTOR signaling pathway through MARCKS. Mouse transplantation tumor assay indicated that miR-188-5p reduced the tumorigenicity of RCC in vivo. MicroRNA-188-5p could be a valuable new molecule for RCC diagnosis and prognosis.

Heavy-ion radiation received during radiotherapy as well as the heavy-ion radiation received during space flight are equally considered harmful. Our previous study showed that TLR4 low toxic agonist, monophosphoryl lipid A (MPLA), alleviated radiation injury resulting from exposure to low-LET radiation. However, the role and mechanism of MPLA in heavy-ion-radiation injury are unclear. This study aimed to investigate the role of MPLA on radiation damage. Our data showed that MPLA treatment alleviated the heavy-ion-induced damage to microstructure and the spleen and testis indexes. The number of karyocytes in the bone marrow from the MPLA-treated group was higher than that in the irradiated group. Meanwhile, western blotting analysis of intestine proteins showed that pro-apoptotic proteins (cleaved-caspase3 and Bax) were downregulated while anti-apoptotic proteins (Bcl-2) were upregulated in the MPLA-treated group. Our in vitro study demonstrated that MPLA significantly improved cell proliferation and inhibited cell apoptosis after irradiation. Moreover, immunofluorescence staining and quantification of nucleic γ-H2AX and 53BP1 foci also suggested that MPLA significantly attenuated cellular DNA damage repair. Collectively, the above evidence supports the potential ability of MPLA to protect against heavy-ion-radiation injury by inhibiting apoptosis and alleviating DNA damage in vivo and vitro, which could be a promising medical countermeasure for the prevention of heavy-ion-radiation injury.

Background Our previous study first showed that ATR-binding long noncoding RNA (lncRNA) is necessary for ATR function and promotes cancer resistance. However, the specific lncRNAs instrumental in ATR activation remain largely unclear, which limits our comprehensive understanding of this critical biological process. Methods RNA immunoprecipitation (RIP) followed by RNA sequencing was employed to identify ATR-binding lncRNAs, which were further validated using RIP-qPCR assays. Immunofluorescence staining and Western blotting were applied to detect the activation of DNA damage repair factors. After the effect of scaRNA2 on cellular sensitivity to DNA-damaging reagents was determined, the effects of scaRNA2 on radiotherapy were investigated in patient-derived organoids and xenograft preclinical models. The clinical relevance of scaRNA2 was also validated in tissues isolated from rectal cancer patients. Results ScaRNA2 was identified as the most enriched ATR-binding lncRNA and was found to be essential for homologous recombination (HR) mediated DNA damage repair. Furthermore, scaRNA2 knockdown abrogated the recruitment of ATR and its substrates in response to DNA damage. Mechanistically, scaRNA2 was observed to be necessary for Exo1-mediated DNA end resection and bridged the MRN complex to ATR activation. Knockdown of scaRNA2 effectively increased the sensitivity of cancer cells to multiple kinds of DNA damage-related chemoradiotherapy. Preclinically, knockdown of scaRNA2 improved the effects of radiotherapy on patient-derived organoids and xenograft models. Finally, an increase in scaRNA2 colocalized with ATR was also found in clinical patients who were resistant to radiotherapy. Conclusions ScaRNA2 was identified as the most abundant lncRNA bound to ATR and was demonstrated to bridge DNA end resection to ATR activation; thus, it could be applied as a potent target for combined cancer treatments with chemoradiotherapy.

Radiotherapy is an important treatment for lung cancer, mainly by triggering DNA double-strand breaks to induce cell death. Blocking DNA damage repair can increase the radiosensitivity of tumor cells. Recent studies have identified long noncoding RNAs as key regulators in DNA damage repair. The lncRNA ANRIL was previously shown to be involved in homologous recombination (HR) repair, but its specific mechanism has not been fully elucidated. The downstream interacting miRNAs of ANRIL were predicted according to miRanda software. Fluorescence quantitative PCR was used to detect the expression levels of ANRIL and candidate miRNAs. Clone formation experiment and cell viability assays detect cell viability after ionizing radiation. Apoptosis assay was used to detect the apoptosis of cells after 8 h of ionizing radiation. Western blot analysis and immunofluorescence assays verified the protein expression levels of the downstream target molecule PARP1 of miR-7-5p and key molecules in the HR pathway. Fluorescent reporter gene experiments were used to verify the interaction between ANRIL and miR-7-5p and between miR-7-5p and PARP1. Bioinformatics analysis and qPCR validation suggested that miR-7-5p might be a downstream molecule of ANRIL. The expression of miR-7-5p was up-regulated after knockdown of ANRIL, and the expression of miR-7-5p was down-regulated after overexpression of ANRIL. Meanwhile, there was a negative correlation between ANRIL and miR-7-5p expression changes before and after ionizing radiation. The luciferase reporter gene assay confirmed the existence of ANRIL binding site with miR-7-5p, and found that transfection of miR-7-5p inhibitor can reduce the radiation sensitivity of ANRIL-KD cells. A downstream target molecule of miR-7-5p related to HR repair, PARP1, was screened through website prediction. Subsequently, it was confirmed by Western blot and luciferase reporter assays that miR-7-5p could down-regulate the expression of PARP1, and there was a miR-7-5p binding site on the 3'UTR of PARP1 mRNA. This suggests that ANRIL may act as a competitive endogenous RNA to bind miR-7-5p and upregulate the expression of PARP1. Western blot and immunofluorescence staining were used to detect the expression changes of HR repair factors in ANRIL-KD cells after ionizing radiation, and it was found that knockdown of ANRIL can inhibit the expression of PARP1, BRCA1 and Rad51, hinder radiation-induced HR repair, and eventually result in resensitizing ANRIL-KD cells to ionizing radiation. Our findings provide evidence that ANRIL targets the miR-7-5p/PARP1 axis to exert its regulatory effect on HR repair, suggesting that altering ANRIL expression may be a promising strategy to overcome radiation resistance.

BACKGROUND:Neoadjuvant radiotherapy has been used as the standard treatment of colorectal cancer (CRC). However, radiotherapy resistance often results in treatment failure. To identify radioresistant genes will provide novel targets for combined treatments and prognostic markers.METHODS:Through high content screening and tissue array from CRC patients who are resistant or sensitive to radiotherapy, we identified a potent resistant gene SUMO specific peptidase 5 (SENP5). Then, the effect of SENP5 on radiosensitivity was investigated by CCK8, clone formation, comet assay, immunofluorescence and flow cytometric analysis of apoptosis and cell cycle to investigate the effect of SENP5 on radiosensitivity. SUMO-proteomic mass spectrometry combined with co-immunoprecipitation assay were used to identify the targets of SENP5. Patient-derived organoids (PDO) and xenograft (PDX) models were used to explore the possibility of clinical application.RESULTS:We identified SENP5 as a potent radioresistant gene through high content screening and CRC patients tissue array analysis. Patients with high SENP5 expression showed increased resistance to radiotherapy. In vitro and in vivo experiments demonstrated that SENP5 knockdown significantly increased radiosensitivity in CRC cells. SENP5 was further demonstrated essential for efficient DNA damage repair in homologous recombination (HR) dependent manner. Through SUMO mass spectrometry analysis, we characterized H2AZ as a deSUMOylation substrate of SENP5, and depicted the SUMOylation balance of H2AZ in HR repair and cancer resistance. By using PDO and PDX models, we found targeting SENP5 significantly increased the therapeutic efficacy of radiotherapy.CONCLUSION:Our findings revealed novel role of SENP5 in HR mediated DNA damage repair and cancer resistance, which could be applied as potent prognostic marker and intervention target for cancer radiotherapy.

Neoadjuvant radiotherapy is a standard treatment for locally advanced rectal cancer, however, resistance to chemoradiotherapy is one of the main obstacles to improving treatment outcomes. The goal of this study was to explore the role of PRDM15 involved in the radioresistance of colorectal cancer and to clarify the underlying mechanism. In present study, we demonstrated that, after DNA damage, PRDM15 was upregulated and localized to DNA damage sites, co-localizing with γ-H2AX. Knockdown of PRDM15 inhibited DNA damage repair and increased radiosensitivity in colorectal cancer cells. Mechanistically, PRDM15 promoted DNA repair by interacting with DNA-PKcs and Ku70/Ku80 complex. In preclinical models of rectal cancer, knockdown of PRDM15 sensitized cell derived xenograft and patient derived xenograft to radiotherapy. In 80 rectal cancer patients treated with neoadjuvant chemoradiotherapy, higher PRDM15 expression was observed associated with weaker tumor regression and poorer prognosis. Our findings revealed that inhibiting PRDM15 was potent to overcome radioresistance through abrogating DNA repair in colorectal cancer cells. Additionally, the expression level of PRDM15 could be applied to predict radiotherapy responsiveness and the outcome of neoadjuvant radiotherapy in rectal cancer patients.

The testes and intestines are highly sensitive to ionizing radiation. Low-dose radiation can cause infertility and enteritis. However, there is a lack of safe and efficient radioprotective agents. This study aims to investigate the radioprotective effects of grape seed proanthocyanidins (GSPs) on testicular and intestinal damage induced by ionizing radiation. In vitro, GSPs reduced the apoptosis and proliferation inhibition of mouse testicular stromal cells TM3 and human small intestinal crypt epithelial cells HIEC induced by ionizing radiation, and alleviated DNA double-strand breaks. In vivo, GSPs ameliorated the pathological damage of the testes and intestines induced by ionizing radiation, and protected the endocrine function of the testes and the barrier function of the intestines. In addition, we preliminarily proved that the radioprotective effect of GSPs is related to its antioxidant effect and inhibition of MAPK signaling pathways. Our results indicate that GSPs are expected to be a safe and effective radioprotective drug.

Abstract As a potent target for cancer therapy, ATR mainly regulates homologous recombination (HR)-mediated DNA damage repair. Our previous study first identified that ATR binding long noncoding RNA (lncRNA) is necessary for ATR function and promotes cancer resistance. However, most important lncRNAs, as critical factors for ATR activation, are largely unknown. In the present study, scaRNA2, the most enriched ATR-binding lncRNA, was identified and well characterized. ScaRNA2 was found to be essential for HR-mediated DNA damage repair. Furthermore, scaRNA2 knockdown abrogated the mobilization of ATR and its substrates in response to DNA damage. Mechanistically, scaRNA2 was observed to be necessary for Exo1-mediated DNA end resection and bridged the MRN complex to ATR activation. Using cancer cells and a cell-derived xenograft model, we demonstrated that lentivirus-based knockdown of scaRNA2 effectively increases sensitivity to multiple kinds of chemoradiotherapy. Preclinically, knockdown of scaRNA2 improved the therapeutic effects of radiotherapy on patient-derived organoids and xenograft models. Finally, upregulation of scaRNA2 colocalized with ATR was also found in clinical patients who are resistant to radiotherapy based on tumor regression grades. In conclusion, we identified scaRNA2 as the most abundant lncRNA bound to ATR and uncovered its mechanism in bridging DNA end resection to ATR activation, which could be applied as a potent target for combined cancer treatments with chemoradiotherapy.

Background To block repairs of DNA damages, especially the DNA double strand break (DSB) repair, can be used to induce cancer cell death. DSB repair depends on a sequential activation of DNA repair factors that may be potentially targeted for clinical cancer therapy. Up to now, many protein components of DSB repair complex remain unclear or poorly characterized. In this study, we discovered that Transglutaminase 2 (TG2) acted as a new component of DSB repair complex. Methods A bioinformatic analysis was performed to identify DNA damage relative genes from dataset from The Cancer Genome Atlas. Immunofluorescence and confocal microscopy were used to monitor the protein localization and recruitment kinetics. Furthermore, immunoprecipitation and mass spectrometry analysis were performed to determine protein interaction of both full-length and fragments or mutants in distinct domain. In situ lung cancer model was used to study the effects cancer therapy in vivo. Results After DSB induction, cytoplasmic TG2 was extensively mobilized and translocated into nucleus after phosphorylated at T162 site by DNA-PKcs. Nuclear TG2 quickly accumulated at DSB sites and directly interacting with Topoisomerase IIα (TOPOIIα) with its TGase domain to promote DSB repair. TG2 deficient cells lost capacity of DSB repair and become susceptible to ionizing radiation. Specific inhibition of TG2-TOPOIIα interaction by glucosamine also significantly inhibited DSB repair, which increased sensitivity in lung cancer cells and engrafted lung cancers. Conclusions These findings elucidate new mechanism of TG2 in DSB repair trough directly interacting with TOPOIIα, inhibition of which provided potential target for overcoming cancer resistance.

Circular RNA (circRNA) is closely related to tumorigenesis and cancer progression. Yet, the roles of cancer-specific circRNAs in the circRNA-related ceRNA network of breast cancer (BRCA) remain unclear. The aim of this study was to construct a ceRNA network associated with circRNA and to explore new therapeutic and prognostic targets and biomarkers for breast cancer. We downloaded the circRNA expression profile of BRCA from Gene Expression Omnibus (GEO) microarray datasets and downloaded the miRNA and mRNA expression profiles of BRCA from The Cancer Genome Atlas (TCGA) database. Differentially expressed mRNAs (DEmRNAs), differentially expressed miRNAs (DEmiRNAs), and differentially expressed circRNAs (DEcircRNAs) were identified, and a competitive endogenous RNA (ceRNA) regulatory network was constructed based on circRNA–miRNA pairs and miRNA–mRNA pairs. Gene ontology and pathway enrichment analyses were performed on mRNAs regulated by circRNAs in ceRNA networks. Survival analysis and correlation analysis of all mRNAs and miRNAs in the ceRNA network were performed. A total of 72 DEcircRNAs, 158 DEmiRNAs, and 2762 DE mRNAs were identified. The constructed ceRNA network contains 60 circRNA–miRNA pairs and 140 miRNA–mRNA pairs, including 40 circRNAs, 30 miRNAs, and 100 mRNAs. Functional enrichment indicated that DEmRNAs regulated by DEcircRNAs in ceRNA networks were significantly enriched in the PI3K-Akt signaling pathway, microRNAs in cancer, and proteoglycans in cancer. Survival analysis and correlation analysis of all mRNAs and miRNAs in the ceRNA network showed that 13 mRNAs and 6 miRNAs were significantly associated with overall survival, and 48 miRNA–mRNA interaction pairs had a significant negative correlation. A PPI network was established, and 21 hub genes were determined from the network. This study provides an effective bioinformatics basis for further understanding of the molecular mechanisms and predictions of breast cancer. A better understanding of the circRNA-related ceRNA network in BRCA will help identify potential biomarkers for diagnosis and prognosis.

溶瘤病毒是肿瘤选择性、多杀伤途径的抗肿瘤制剂,其直接杀伤肿瘤细胞达到溶瘤效果,并释放肿瘤抗原,激活机体抗肿瘤免疫应答.溶瘤病毒可搭载多种细胞因子,如GM-CSF、IL-2等,在小鼠模型和临床患者治疗中均被证实能够起到有效的抗肿瘤作用.溶瘤病毒细胞载体的应用使溶瘤病毒制剂在临床转化与治疗中得到更好的推广,其联合其他治疗手段共同治疗肿瘤已成为肿瘤临床治疗的重要研究方向.