Therapeutic hyperthermia regulates complement C3 activation and suppresses tumor development through HSPA5/NFκB/CD55 pathway in nasopharyngeal carcinoma.

Nasopharyngeal carcinoma (NPC) is endemic in Southern China and Southeast Asia. Hyperthermia is widely used in combination with chemotherapy and radiotherapy to enhance therapeutic efficacy in NPC treatment, but the underlying anti-tumor mechanisms of hyperthermia remain unclear. Complement C3 has been reported to participate in the activation of immune system in the tumor microenvironment, leading to tumor growth inhibition. In this study, we aimed to explore the effect and mechanisms of hyperthermia and investigate the functional role of complement C3 in NPC hyperthermia therapy (HT). The serum levels of complement C3 before and after hyperthermia therapy in patients with NPC were analyzed. NPC cell lines SUNE1 and HONE1 were used for in vitro experiment to evaluate the function of complement C3 and HT on cell proliferation and apoptosis. SUNE1 xenograft mouse model was established and tumor-bearing mice were treated in water bath at a constant temperature of 43°C. Tumor samples were collected at different time points to verify the expression of complement C3 by immunohistochemical staining and western blot. The differential expressed genes after hyperthermia were analyzed by using RNA sequencing. We found that complement could enhance hyperthermia effect on suppressing proliferation and promoting apoptosis of tumor cells in NPC. Hyperthermia decreased the mRNA expression of complement C3 in tumor cells, but promoted the aggregation and activation circulating C3 in NPC tumor tissue. By using in vitro hyperthermia-treated NPC cell lines and SUNE1 xenograft tumor-bearing mice, we found that the expression of heat shock protein 5 (HSPA5) was significantly upregulated. Knockdown of HSPA5 abrogated the anti-tumor effect of hyperthermia. Moreover, we demonstrated that hyperthermia downregulated CD55 expression via HSPA5/NFκB (P65) signaling and activated complement cascade. Our findings suggest that therapeutic hyperthermia regulates complement C3 activation and suppresses tumor development via HSPA5/NFκB/CD55 pathway in NPC.

PD-L1 expression as biomarker of efficacy of PD-1/PD-L1 checkpoint inhibitors in metastatic triple negative breast cancer: A systematic review and meta-analysis.

Background: Inhibitors of programmed cell death 1 (PD-1)/programmed cell death ligand 1(PD-L1) checkpoint have been approved for metastatic triple negative breast cancer (mTNBC) in patients positive for PD-L1 expression. Negative results from the recent phase III trials (IMPassion131 and IMPassion132) have raises questions on the efficacy of PD-1/PD-L1 checkpoint inhibitors and the predictive value of PD-L1 expression. Here we attempt to systematically analyze the biomarker value of PD-L1 expression for predicting the response of PD-1/PD-L1 checkpoint inhibitors in mTNBC. Materials and methods: PubMed database was searched until Dec 2021 for studies evaluating PD-1/PD-L1 checkpoint inhibitors plus/minus chemotherapy in mTNBC. Outcome of interest included objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). Review Manager (RevMan) version 5.4. was used for data-analysis. Results: In total, 20 clinical trials comprising 3962 mTNBC patients (ICT: 2665 (67%); CT: 1297 (33%) were included in this study. Overall ORR was 22% (95%CI, 14-30%) and significant improvement was observed for PD-L1+ patients (ORR 1.78 [95%CI, 1.45-2.19], p<0.00001) as compared to PD-L1- cohort. Pooled outcome also indicated a significant 1-year PFS and 2-year OS advantage for patients with PD-L1 expression (1-year PFS: ORR 1.39 [95%CI, 1.04-1.85], p=0.02; I2 = 0%; 2-year OS: (ORR 2.47 [95%CI, 1.30-4.69], p=0.006; I2 = 63%). Subgroup analysis indicated that PD-L1 expression can successfully predict tumor response and 2-year OS benefit in mTNBC patients regardless of the type of investigating agent, line of treatment administration, and to some extent the type of treatment. Biomarker ability of PD-L1 expression to predict 1-year PFS was slightly better with pembrolizumab (p=0.09) than atezolizumab (p=0.18), and significantly better when treatment was administered in the first-line setting (OR 1.38 [95%CI, 1.02-1.87], p=0.04) and chemotherapy was added (OR 1.38 [95%CI, 1.02-1.86], p=0.03). Immune-related toxicity of any grade and grade≥3 was 39% (95%CI, 26%-52%) and 10% (95%CI, 8%-13%), respectively. Conclusions: PD-L1 expression can predict objective response rate and 2-year OS in mTNBC patients receiving PD-1/PD-L1 checkpoint inhibitors. One-year PFS is also predicted in selected patients. PD-L1 expression can be a useful biomarker of efficacy of PD-1/PD-L1 checkpoint inhibitors in mTNBC.

CMTM6 as a candidate risk gene for cervical cancer: Comprehensive bioinformatics study.

Background: CKLF like MARVEL transmembrane domain containing 6 (CMTM6) is an important programmed cell death 1 ligand 1 regulator (PD-L1). CMTM6 was reported as an important regulator of PD-L1 by promoting PD-L1 expression in tumor cells against T cells. However, the function of CMTM6 in cervical cancer is not well characterized. In addition, the role of CMTM6 in the induction of epithelial-mesenchymal transition (EMT) in the context of cervical cancer is unknown. Methods: In this study, we evaluated the role of CMTM6, including gene expression analysis, miRNA target regulation, and methylation characteristic, using multiple bioinformatics tools based on The Cancer Genome Atlas (TCGA) database. The expression of CMTM6 in cervical cancer tissues and non-cancerous adjacent tissues was assessed using immunohistochemistry. In vitro and in vivo function experiments were performed to explore the effects of CMTM6 on growth and metastasis of cervical cancer. Results: Human cervical cancer tissues showed higher expression of CMTM6 than the adjacent non-cancerous tissues. In vitro assays showed that CMTM6 promoted cervical cancer cell invasion, migration, proliferation, and epithelial-mesenchymal transition via activation of mitogen-activated protein kinase (MAPK) c-jun N-terminal kinase (JNK)/p38 signaling pathway. We identified transcription factors (TFs), miRNAs, and immune cells that may interact with CMTM6. Conclusion: These results indicate that CMTM6 is a potential therapeutic target in the context of cervical cancer.

Pyroptosis relates to tumor microenvironment remodeling and prognosis: A pan-cancer perspective.

Background and aim: Pyroptosis is an inflammatory form of programmed cell death implicated in inflammation and disease. Moreover, inducing pyroptosis has been appreciated as anti-cancer therapy for its ability to unleash anti-cancer immune responses. Methods: Utilizing the data available in The Cancer Genome Atlas (TCGA), pyroptosis-related genes' (PRGs) expression, genomic aberrations, and clinical significance were systematically analyzed in pan-cancer. A GSVA score was obtained to rate pyroptosis level and divide the cancers into pyroptosis-low and pyroptosis-high groups. Immunohistochemistry (IHC) was used to evaluate the differential expression of major PRGs (GSDMC, GSDMD, GSDME, NLRP3, NLRC4, IL1B) in selected tumor types (COAD, HNSC, KIRC, LIHC, LUAD, LUSC). Selection of tumors for immunohistochemistry (IHC) was based on their expression pattern in TCGA cancers, clinical relevance, tumor epidemiology, and sample availability. Results: Differential expression of PRGs was evident in various cancers and associated with prognosis which was driven by genomic variations and epigenetic abnormalities, such as single nucleotide variations (SNVs), copy number variation (CNV) and DNA methylation level. For example, methylation of PRGs in lower grade glioma (LGG), uveal melanoma (UVM) and kidney renal clear cell carcinoma (KIRC) were predictive of improved survival as upregulation of PRGs was risky in these cancers. Pyroptosis level significantly differentiated tumor from normal samples in 15 types of cancers, exhibited a progressive trend with cancer stage, observed variation among cancer subtypes, and showed a significant association with cancer prognosis. Higher pyroptosis level was associated with worst prognosis in majority of the cancers in terms of OS (KIRC, LGG, and UVM), PFS (GBM, KIRC, LGG, PRAD, THCA, and THYM) and DSS (KIRC and LGG) as estimated by Kaplan-Meier survival curves. Moreover, Pyroptosis level was strongly indicative of a hot tumor immune microenvironment with high presence of CD8+ T cell and other T cell subtypes. Several oncogenic pathways, such as P53 pathway, DNA repair, KRAS signaling, epithelial-mesenchymal transition (EMT), IL6 JAK STAT3 signaling, IL2 STAT5 signaling, PI3K AKT MTOR signaling and angiogenesis, were enriched in pyroptosis-hi subgroups across cancers. Conclusions: Genetic alterations in PRGs greatly influence the pyroptosis level and cancer prognosis. A relatively hot tumor immune microenvironment was associated with pyroptosis irrespective of the cancer prognosis. Overall, our study reveals the critical role of pyroptosis in cancer and highlights pyroptosis-based therapeutic vulnerabilities.

CMTM6 promotes migration, invasion, and EMT by interacting with and stabilizing vimentin in hepatocellular carcinoma cells.

BACKGROUND: CKLF like MARVEL transmembrane domain containing 6 (CMTM6) has been associated with the development in many kinds of cancers. However, the roles of CMTM6 in hepatocellular carcinoma (HCC) are largely unknown. Thus, the present study aimed to investigate the function of CMTM6 in HCC. METHODS: We analysed CMTM6 levels and functions using human HCC cell lines, paired HCC and adjacent non-tumorous tissues, and a tissue microarray. CMTM6 expression was silenced using short hairpin RNAs and its was overexpressed from a lentivirus vector. CMTM6 mRNA and protein levels were determined using quantitative real-time reverse transcription PCR and western blotting, respectively. Proliferation, colony formation, migration, and invasion were assessed using a Cell counting kit-8, colony formation, wound-healing, and Matrigel invasion assays, respectively. Immunohistochemistry was used to score the expression of CMTM6 in tissue samples. The localization and binding partners of CMTM6 were investigated using immunofluorescence and coimmunoprecipitation experiments, respectively. A mouse xenograft model was used for in vivo studies. RESULTS: Compared with that in adjacent, non-cancerous tissue, Here, CMTM6 levels were increased in HCC tissue samples. Silencing of CMTM6 suppressed the proliferation, migration, and invasion of HCC cells. Conversely, CMTM6 overexpression enhanced HCC cell invasion, migration, and proliferation. Mechanistically, CMTM6 physically interacts with and stabilizes vimentin, thus inducing epithelial-mesenchymal transition (EMT), which promotes proliferation, migration and invasion. Importantly, in HCC tissues, CMTM6 expression correlated positively with vimentin levels. Poor prognosis of HCC was associated significantly with higher CMTM6 expression. CONCLUSIONS: CMTM6 has an important function in HCC proliferation, migration, and invasion, via its interaction with and stabilization of vimentin. CMTM6 might represent a potential biomarker and therapeutic target to treat HCC.

Roles of diencephalon/mesencephalon homeobox 1 in the development and prognosis of hepatocellular carcinoma.

INTRODUCTION AND OBJECTIVES: The oncogene diencephalon/mesencephalon homeobox 1 (DMBX1) is widely overexpressed in a variety of human cancers. The present study aimed to analyze the expression and clinical importance of DMBX1 in nonneoplastic tissues and tumor tissues from patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: DMBX1 expression in HCC and adjacent nontumor tissues was analyzed using immunohistochemical staining. Chi-square tests were applied to compare DMBX1 expression between the tumors and the adjacent normal tissues. We explored the correlation of DMBX1 expression with clinicopathological factors and its effect on the prognosis of HCC. Finally, we investigated the role of DMBX1 in HCC via knockdown experiments, which analyzed changes in cell invasion, cell proliferation and epithelial-mesenchymal transition (EMT) biomarkers (E-cadherin, N-cadherin, vimentin). The mRNAs that were coexpressed with DMBX1 in HCC, based on the TCGA cohort (n = 366), were obtained from the cBioPortal database. RESULTS: The average score for DMBX1 expression was significantly different (P < 0.001) between HCC and paired adjacent nontumor tissues, and DMBX1 expression correlated with hepatitis B virus (HBV) infection, tumor size, metastasis, and tumor node metastasis (TNM) stage (P < 0.05). A multivariate Cox regression analysis identified significant correlations of DMBX1 expression with tumor metastasis, TNM stage, and tumor capsule. Moreover, Kaplan-Meier survival analysis revealed an association between DMBX1 overexpression and shorter overall survival of patients with HCC (P < 0.05). In HCC cell lines, silencing DMBX1 markedly inhibited migration, proliferation and EMT markers. The mRNAs that were negatively (R ≤ -0.25, n = 1094) or positively (R ≥ 0.25, n = 2906) coexpressed with DMBX1 mRNA were selected for further Gene Ontology enrichment analysis, and the results revealed that the predicted functions of DMBX1 in HCC support the in vitro experimental results. CONCLUSIONS: Our data provide evidence that DMBX1 overexpression is associated with HCC metastasis and poor prognosis, suggesting that DMBX1 represents a therapeutic target in HCC.

Regulatory coupling between long noncoding RNAs and senescence in irradiated microglia.

BACKGROUND: Microglia have been implicated in the pathogenesis of radiation-induced brain injury (RIBI), which severely influences the quality of life during long-term survival. Recently, irradiated microglia were speculated to present an aging-like phenotype. Long noncoding RNAs (lncRNAs) have been recognized to regulate a wide spectrum of biological processes, including senescence; however, their potential role in irradiated microglia remains largely uncharacterized. METHODS: We used bioinformatics and experimental methods to identify and analyze the senescence phenotype of irradiated microglia. Western blotting, enzyme-linked immunosorbent assays, immunofluorescence, and quantitative real-time reverse transcription-polymerase chain reaction were performed to clarify the relationship between the radiation-induced differentially expressed lncRNAs (RILs) and the distinctive molecular features of senescence in irradiated microglia. RESULTS: We found that the senescence of microglia could be induced using ionizing radiation (IR). A mutual regulation mode existed between RILs and three main features of the senescence phenotype in irradiated microglia: inflammation, the DNA damage response (DDR), and metabolism. Specifically, for inflammation, the expression of two selected RILs (ENSMUST00000190863 and ENSMUST00000130679) was dependent on the major inflammatory signaling pathways of nuclear factor kappa B (NF-κB) and mitogen-activated protein kinase (MAPK). The two RILs modulated the activation of NF-κB/MAPK signaling and subsequent inflammatory cytokine secretion. For the DDR, differential severity of DNA damage altered the expression profiles of RILs. The selected RIL, ENSMUST00000130679, promoted the DDR. For metabolism, blockade of sterol regulatory element-binding protein-mediated lipogenesis attenuated the fold-change of several RILs induced by IR. CONCLUSIONS: Our findings revealed that certain RILs interacted with senescence in irradiated microglia. RILs actively participated in the regulation of senescence features, suggesting that RILs could be promising intervention targets to treat RIBI.