SEC61G promotes breast cancer development and metastasis via modulating glycolysis and is transcriptionally regulated by E2F1

Single-cell and spatial transcriptomics reveals the key role of MCAM+ tip-like endothelial cells in osteosarcoma metastasis

Osteosarcoma, the most common primary malignant bone tumor in children and adolescents, is highly aggressive and prone to metastasis. Endothelial cells (ECs) are involved in angiogenesis and play a key role in promoting the metastasis of tumor. However, research on tip-like ECs within osteosarcoma was extremely rare. In this study, a single-cell atlas of ECs was constructed using single-cell transcriptomic data. It was found that tip-like ECs were abundant in the primary tumors and metastatic foci. Gene sets score analysis indicated their enrichment in pathways associated with angiogenesis and metastasis. What's more, MCAM was highly expressed in tip-like ECs and was likely to promote the metastasis of osteosarcoma. MCAM was also found to be highly expressed in the ECs of metastatic lymph nodes when compared to normal lymph node samples. Meanwhile, spatial transcriptomics data confirmed the presence of MCAM-positive ECs in metastatic lymph node, closely localized to osteoblasts. In vitro assays, including qRT-PCR, tube formation, and immunofluorescence, validated the role of the MCAM gene in promoting angiogenesis. In conclusion, tip-like ECs may promote tumor metastasis by enhancing angiogenesis. MCAM was a functional gene for tip-like ECs and could serve as a target for the treatment of osteosarcoma.

Exposure to an environmentally relevant concentration of chlorpyrifos induces transcriptional changes and neurotoxicity in Poecilia gillii without clear behavioral effects

Overusing chlorpyrifos (CPF) in tropical countries such as Costa Rica poses a potential risk to freshwater ecosystems. This study investigated the effects of transient exposure to an environmentally relevant CPF concentration on the native fish species Poecilia gillii, employing a comprehensive approach that evaluated multiple levels of biological organization. Using RT-qPCR, we quantified transcript changes in genes involved in various biological processes, including inflammation and apoptosis; annexin A1 (anxa1b), cytokine regulation; cytokine-inducible SH2-containing protein (cish), redox reactions; NADH oxidoreductase subunit A2 (ndufa2), protein translocation; Sec61 gamma subunit (sec61g), and biotransformation; glutathione S-transferase rho (gstr). Additionally, we measured biochemical biomarkers such as phase I; 7-ethoxyresorufin-O-deethylase (EROD) and phase II; glutathione S-transferase (GST) biotransformation enzymes, oxidative stress markers; catalase (CAT) and lipid peroxidation (LPO), and conducted behavioral tests to assess swimming fitness and antipredator reactions. Neurotoxicity was assessed by measuring brain and muscle tissue cholinesterase (ChE) activity. Following 48 h of exposure to 5.5 µg/L CPF, we observed significant downregulation of the sec61g and gstr genes, decreased CAT activity, and neurotoxic effects, as indicated by reduced ChE activity in muscle. Although no significant behavioral changes were detected, our results suggest that short-term exposure to environmentally relevant CPF concentrations can disrupt gene expression, compromising biotransformation and protein synthesis in P. gillii juveniles. Moreover, the observed neurotoxicity, which is consistent with the mechanism of action of CPF, may lead to subtle behavioral changes. This study provides evidence of the sublethal effects of CPF on nontarget organisms, highlighting the importance of considering gene expression changes when assessing CPF toxicity.

MCM8 promotes NR4A1-mediated E2F1 transcription and facilitates renal cell carcinoma through enhancing aerobic glycolysis

Renal cell carcinoma (RCC) is a type of renal malignancy originated from the urinary tubular epithelial system. Despite its high incidence, the molecular mechanisms driving its pathogenesis remain poorly understood, limiting therapeutic advancements. This study explored the link between MCM8 and RCC progression. MCM8 displays significantly high expression in RCC tissues and was closely associated with RCC pathological staging. Knocking down endogenous MCM8 in RCC cells significantly suppressed malignant phenotypes, while simultaneously inducing apoptosis. Similarly, in vivo experiments confirmed these findings, showing a pronounced reduction in tumor growth upon MCM8 silencing. Mechanistic investigations revealed that MCM8 regulates E2F1 expression by interacting with the transcription factor NR4A1, thereby affecting E2F1 transcriptional activity. Additionally, MCM8 and E2F1 collaboratively influence aerobic glycolysis and the cellular behavior of RCC cells. In conclusion, this study identifies MCM8 as a tumor-promoting factor in RCC, with its oncogenic role potentially mediated by its regulation of E2F1 expression.

SEC61G Facilitates Brain Metastases via Antagonizing PGAM1 Ubiquitination and Immune Microenvironment Remodeling in Non-Small Cell Lung Cancer

Background: Brain metastases are a leading cause of mortality in non-small cell lung cancer (NSCLC), yet their molecular mechanisms remain unclear. SEC61G, a subunit of the SEC61 translocon, has been implicated in tumor progression but its role in brain metastases is unknown. This study explores how SEC61G contributes to brain metastases by driving metabolic reprogramming and immune microenvironment remodeling. Methods: Brain-metastatic NSCLC cell lines were established through in vivo selection in a mouse model. SEC61G expression was analyzed via transcriptomics, immunohistochemistry, multiplex immunofluorescence, and patient datasets. Functional assays were used to assess SEC61G's role in glycolysis, TLS formation, and immune interactions, with a focus on the SEC61G-PGAM1 axis. Pharmacological inhibitors and co-culture systems were employed to validate findings. Results: SEC61G was identified as a key upregulated gene in brain metastases based on transcriptomic data from patient-derived samples and mouse models. Higher SEC61G expression in brain metastases correlated with advanced tumor stages and poor survival in NSCLC patients. Mechanistically, SEC61G promoted brain metastasis by stabilizing the key glycolytic enzyme PGAM1. This occurred through a novel mechanism of competitive inhibition of PGAM1 ubiquitination: SEC61G directly antagonized the E3 ubiquitin ligase UBE3C, preventing PGAM1 degradation via the proteasome pathway. Stabilized PGAM1 enhanced glycolysis and regulated oxidative phosphorylation, driving metabolic reprogramming that supported brain metastatic colonization. Moreover, SEC61G reshaped the tumor immune microenvironment by promoting microglial M2 polarization and suppressing M1 polarization, accompanied by increased secretion of IL-6 and IL-10. These immune effects were dependent on PGAM1, as its pharmacological inhibition reversed SEC61G-induced M2 polarization and restored CD8+ T cell infiltration. In vivo and clinical studies confirmed that high SEC61G expression in brain metastases correlated with excessive M2 microglia, reduced immune surveillance, and poor patient outcomes. Immunoprofiling revealed a striking gradient of SEC61G expression across tertiary lymphoid structures (TLS) maturation stages: SEC61G levels were highest in TLS-absent samples and CD206+ microglia infiltration, intermediate in samples with immature TLS, and lowest in those with mature TLS. Conclusion: In conclusion, this study identifies a novel mechanism in which SEC61G drives NSCLC brain metastases by competitively inhibiting UBE3C-mediated ubiquitination of PGAM1, stabilizing PGAM1 and enhancing glycolysis. In addition to metabolic reprogramming, SEC61G impairs TLS maturation, suppresses adaptive immune responses, and facilitates immune evasion, contributing to brain metastatic colonization. These findings highlight SEC61G as a key regulator of brain metastasis and a promising therapeutic target for NSCLC patients with brain metastases.

Activation of ferritin light chain (FTL) by transcription factor salmonella pathogenicity island 1 modulates glycolysis to drive metastasis of ovarian cancer cells

BACKGROUND

Ovarian cancer (OC) is the most lethal gynecological cancer often diagnosed at an advanced stage due to a lack of effective biomarkers. Ferritin light chain (FTL) is implicated in the development of various cancers, but its impact on OC remains unknown.

RESEARCH DESIGN AND METHODS

Bioinformatics methods were utilized to analyze FTL. Quantitative real-time polymerase chain reaction, western blot, and immunohistochemistry were employed for expression detection, and cell counting kit- 8, and transwell assays were for cell biological functions assessment. Extracellular acidification rate, oxygen consumption rate, and glycolytic metabolite contents were measured. Dual-luciferase and chromatin immunoprecipitation assay validated binding relationship. Xenografted tumor models in nude mice verified the role of FTL in vivo.

RESULTS

Cell function experiments revealed that FTL facilitated proliferation, migration, and invasion of OC cells. Rescue experiments unveiled that 2-Deoxy-D-glucose attenuated stimulation on OC cell metastasis and glycolysis by FTL overexpression. Salmonella pathogenicity island 1 (SPI1) up-regulated FTL expression to promote glycolysis and metastasis. FTL knockdown inhibited tumor growth and suppressed glycolysis and cell metastasis in vivo, while SPI1 overexpression attenuated these effects.

CONCLUSIONS

This study demonstrated pro-metastatic mechanisms of transcription factor SPI1/FTL axis in OC and suggested it as a potential target for treating OC metastasis.

TIFA enhances glycolysis through E2F1 and promotes the progression of glioma

OBJECTIVE

TRAF interacting protein with forkhead associated domain (TIFA) influence progression of many cancers. However, its role in glioma remains to be explored. This study investigated the function of TIFA in glioma.

METHODS

The TIFA expression in glioma and patient outcomes were analyzed using online database. Gene set enrichment analysis (GSEA) revealed related mechanisms of TIFA in glioma. TIFA's effects on glioma glycolysis and growth were assessed using in vitro and in vivo experiments. Moreover, luciferase reporter and ChIP were employed to explore the interactions among E2F1, GLUT1, HK2, and LDHA. The subcutaneous xenograft assay further elaborated the effects of TIFA in glioma.

RESULTS

We found overexpressed TIFA in glioma. Moreover, the high TIFA expression was associated with poor prognosis of glioma. Furthermore, GSEA indicated that overexpressed TIFA promoted E2F1 and glycolysis. Knockdown of TIFA decreased glioma development in cell and mice. TIFA knockdown down-regulated the expression of E2F1, GLUT1, HK2, and LDHA.

CONCLUSIONS

The study provides evidence that TIFA regulates E2F1 expression in glioma cells and promotes the proliferation, migration, and glycolysis. TIFA might be an advantageous therapeutic strategy against glioma.

Curcumin suppresses the malignant phenotype of laryngeal squamous cell carcinoma through downregulating E2F1 to inhibit FLNA

Curcumin is a kind of polyphenol substance extracted from the rhizome of Curcuma longa. Because of its good biological activity and pharmacological effects, it has been used in anti-tumor research. The aim of this study was to investigate the anti-cancer mechanism of curcumin on laryngeal squamous cell carcinoma (LSCC). Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to check the expression level of transcription factor E2F1 (E2F1) and filamin A (FLNA) mRNA. E2F1 and FLNA protein and proliferation-associated protein were detected through western blot. Cell viability was showed by MTT assay, and flow cytometry was used to exhibit cell cycle distribution and cell apoptosis. Tube formation assay was used to detect the angiogenesis ability of cells. Transwell was used as a method to observe cell migration and invasion. The online website JASPAR predicted the binding site of E2F1 and FLNA promoter, and chromatin immunoprecipitation (ChIP) and dual-luciferase report experiment verified the combination. Curcumin treatment made LSCC cells viability reduce, cell cycle retardant, angiogenesis decrease, metastasis inhibition and apoptosis increase. And curcumin treatment could downregulate the expression of E2F1, and E2F1 overexpression would reverse the influence of curcumin treatment in LSCC cells. Moreover, E2F1 could bind to FLAN promoter and promote FLNA expression. The expression level of FLNA was higher in LSCC tissue and cells compared with normal tissue and cells. E2F1 knockdown inhibited malignant phenotype of LSCC cells, which would be reversed by FLNA addition. In addition, FLNA had high level in LSCC tissue and cells. Curcumin regulated FLNA expression via inhibiting E2F1. Finally, in vivo assay showed that curcumin inhibition restrained LSCC tumor formation. Curcumin downregulated FLNA expression through inhibiting E2F1, thereby suppressing the malignant phenotype and angiogenesis of LSCC cells, which was a new regulatory pathway in LSCC.

SEC61 translocon gamma subunit is correlated with glycolytic activity, epithelial mesenchymal transition and the immune suppressive phenotype of lung adenocarcinoma

Lung adenocarcinoma (LUAD) remains a predominant cause of cancer-related mortality globally, underscoring the urgency for targeted therapeutic strategies. The specific role and impact of the SEC61 translocon gamma subunit (SEC61G) in LUAD progression and metastasis remain largely unexplored. In this study, we use a multifaceted approach, combining bioinformatics analysis with experimental validation, to elucidate the pivotal role of SEC61G and its associated molecular mechanisms in LUAD. Our integrated analyses reveal a significant positive correlation between SEC61G expression and the glycolytic activity of LUAD, as evidenced by increased fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET)/CT scans. Further investigations show the potential influence of SEC61G on metabolic reprogramming, which contributes to the immunosuppressive tumor microenvironment (TME). Remarkably, we identify a negative association between SEC61G expression levels and the infiltration of critical immune cell populations within the TME, along with correlations with immune checkpoint gene expression and tumor heterogeneity scores in LUAD. Functional studies demonstrate that SEC61G knockdown markedly inhibits the migration of A549 and H2030 LUAD cells. This inhibitory effect is accompanied by a significant downregulation of key regulators of tumor progression, including hypoxia-inducible factor-1 alpha (HIF-1α), lactate dehydrogenase A, and genes involved in the epithelial-mesenchymal transition pathway. In conclusion, our comprehensive analyses position SEC61G as a potential prognostic biomarker intricately linked to glycolytic metabolism, the EMT pathway, and the establishment of an immune-suppressive phenotype in LUAD. These findings underscore the potential of SEC61G as a therapeutic target and predictive marker for immunotherapeutic responses in LUAD patients.

Diastereomers of Coibamide A Show Altered Sec61 Client Selectivity and Ligand-Dependent Activity against Patient-Derived Glioma Stem-like Cells

Coibamide A (CbA) is a cyanobacterial lariat depsipeptide that selectively inhibits multiple secreted and integral membrane proteins from entering the endoplasmic reticulum secretory pathway through binding the alpha subunit of the Sec61 translocon. As a complex peptide-based macrocycle with 13 stereogenic centers, CbA is presumed to adopt a conformationally restricted orientation in the ligand-bound state, resulting in potent antitumor and antiangiogenic bioactivity. A stereochemical structure-activity relationship for CbA was previously defined based on cytotoxicity against established cancer cell lines. However, the ability of synthetic isomers to inhibit the biosynthesis of specific Sec61 substrates was unknown. Here, we report that two less toxic diastereomers of CbA, [L-Hiv2]-CbA and [L-Hiv2, L-MeAla11]-CbA, are pharmacologically active Sec61 inhibitors. Both compounds inhibited the expression of a secreted reporter (Gaussia luciferase), VEGF-A, and a Type 1 membrane protein (VCAM1), while [L-Hiv2]-CbA also decreased the expression of ICAM1 and BiP/GRP78. Analysis of 43 different chemokines in the secretome of SF-268 glioblastoma cells revealed different inhibitory profiles for the two diastereomers. When the cytotoxic potential of CbA compounds was compared against a panel of patient-derived glioblastoma stem-like cells (GSCs), Sec61 inhibitors were remarkably toxic to five of the six GSCs tested. Each ligand showed a distinct cytotoxic potency and selectivity pattern for CbA-sensitive GSCs, with IC50 values ranging from subnanomolar to low micromolar concentrations. Together, these findings highlight the extreme sensitivity of GSCs to Sec61 modulation and the importance of ligand stereochemistry in determining the spectrum of inhibited Sec61 client proteins.

Knockdown of circ_0044226 promotes endoplasmic reticulum stress-mediated autophagy and apoptosis in hepatic stellate cells via miR-4677-3p/SEC61G axis

Downregulation of circ_0044226 has been demonstrated to reduce pulmonary fibrosis, but the role of circ_0044226 in liver fibrosis remains to be explored. In this work, we found that circ_0044226 expression was upregulated during liver fibrosis. Knockdown of circ_0044226 inhibited proliferation, promoted autophagy and apoptosis of hepatic stellate cell LX-2. Bioinformatic analysis and dual luciferase reporter assays confirmed the interaction between circ_0044226, miR-4677-3p and SEC61G. Mechanistically, knockdown of circ_0044226 suppressed SEC61G expression by releasing miR-4677-3p, thereby enhancing endoplasmic reticulum stress. Overexpression of SEC61G or endoplasmic reticulum stress inhibitor 4-phenylbutiric acid partially reversed the effect of knockdown circ_0044226 on LX-2 cell function. In vivo experiments showed that inhibition of circ_0044226 attenuated CCL4-induced liver fibrosis in mice. These imply that circ_0044226 may be a potential target for the treatment of liver fibrosis.

An original aneuploidy-related gene model for predicting lung adenocarcinoma survival and guiding therapy

Aneuploidy is a hallmark of cancers, but the role of aneuploidy-related genes in lung adenocarcinoma (LUAD) and their prognostic value remain elusive. Gene expression and copy number variation (CNV) data were enrolled from TCGA and GEO database. Consistency clustering analysis was performed for molecular cluster. Tumor microenvironment was assessed by the xCell and ESTIMATE algorithm. Limma package was used for selecting differentially expressed genes (DEGs). LASSO and stepwise multivariate Cox regression analysis were used to establish an aneuploidy-related riskscore (ARS) signature. GDSC database was conducted to predict drug sensitivity. A nomogram was designed by rms R package. TCGA-LUAD patients were stratified into 3 clusters based on CNV data. The C1 cluster displayed the optimal survival advantage and highest inflammatory infiltration. Based on integrated intersecting DEGs, we constructed a 6-gene ARS model, which showed effective prediction for patient's survival. Drug sensitivity test predicted possible sensitive drugs in two risk groups. Additionally, the nomogram exhibited great predictive clinical treatment benefits. We established a 6-gene aneuploidy-related signature that could effectively predict the survival and therapy for LUAD patients. Additionally, the ARS model and nomogram could offer guidance for the preoperative estimation and postoperative therapy of LUAD.

Transcription factor TEAD4 facilitates glycolysis and proliferation of gastric cancer cells by activating PKMYT1

BACKGROUND

Gastric cancer (GC) ranks third for cancer deaths worldwide, and glycolysis is a hallmark of several cancers, including GC. TEAD4 plays a role in establishing an oncogenic cascade in cancers, including GC. Whether TEAD4 can influence the glycolysis of GC cells remains uncovered. Hence, this study attempted to investigate the impact on glycolysis of GC cells by TEAD4.

METHODS

By using bioinformatics analysis, differentially expressed mRNAs were screened, and downstream regulatory genes were predicted. Expression levels of TEAD4 and PKMYT1 were assessed by qRT-PCR. The binding sites between TEAD4 and PKMYT1 were predicted by the JASPAR database, meanwhile their modulatory relationship was confirmed through dual-luciferase assay and chromatin Immunoprecipitation (ChIP). Cell viability and proliferation were assayed via CCK-8 and colony formation assays. Glycolysis was measured by assaying extracellular acidification rate, oxygen consumption rate, and production of pyruvic acid, lactate, citrate, and malate. Expression levels of proteins (HK-2 and PKM2) related to glycolysis were assessed by Western blot.

RESULTS

TEAD4 was upregulated in GC tissues and cells. TEAD4 knockdown substantially repressed glycolysis and proliferation of GC cells. PKMYT1, the target gene downstream of TEAD4, was identified via bioinformatics prediction, and its expression was elevated in GC. Dual-luciferase and ChIP assay validated the targeted relationship between the promoter region of PKMYT1 and TEAD4. As revealed by rescue experiments, the knockdown of TEAD4 reversed the stimulative effect on GC cell glycolysis and proliferation by forced expression of PKMYT1.

CONCLUSION

TEAD4 activated PKMYT1 to facilitate the proliferation and glycolysis of GC cells. TEAD4 and PKMYT1 may be possible therapeutic targets for GC.

Single-cell analysis reveals exosome-associated biomarkers for prognostic prediction and immunotherapy in lung adenocarcinoma

BACKGROUND

Exosomes play a crucial role in tumor initiation and progression, yet the precise involvement of exosome-related genes (ERGs) in lung adenocarcinoma (LUAD) remains unclear.

METHODS

We conducted a comprehensive investigation of ERGs within the tumor microenvironment (TME) of LUAD using single-cell RNA sequencing (scRNA-seq) analysis. Multiple scoring methods were employed to assess exosome activity (EA). Differences in cell communication were examined between high and low EA groups, utilizing the "CellChat" R package. Subsequently, we leveraged multiple bulk RNA-seq datasets to develop and validate exosome-associated signatures (EAS), enabling a multifaceted exploration of prognosis and immunotherapy outcomes between high- and low-risk groups.

RESULTS

In the LUAD TME, epithelial cells demonstrated the highest EA, with even more elevated levels observed in advanced LUAD epithelial cells. The high-EA group exhibited enhanced intercellular interactions. EAS were established through the analysis of multiple bulk RNA-seq datasets. Patients in the high-risk group exhibited poorer overall survival (OS), reduced immune infiltration, and decreased expression of immune checkpoint genes. Finally, we experimentally validated the high expression of SEC61G in LUAD cell lines and demonstrated that knockdown of SEC61G reduced the proliferative capacity of LUAD cells using colony formation assays.

CONCLUSION

The integration of single-cell and bulk RNA-seq analyses culminated in the development of the profound and significant EAS, which imparts invaluable insights for the clinical diagnosis and therapeutic management of LUAD patients.

SEC61 translocon subunit gamma enhances low-dose cisplatin-induced cancer-stem cell properties of head and neck squamous cell carcinoma via enhancing Ca2+-mediated autophagy

Background/purpose

High SEC61 translocon subunit gamma (SEC61G) expression is associated with an unfavorable prognosis in patients with head and neck squamous cell carcinoma (HNSCC), but the underlying mechanisms remain poorly understood.

Materials and methods

HNSCC representative cell lines SCC15 and CAL27 were used to explore the regulation of SEC61G on Ca2+ leak from the endoplasmic reticulum (ER). Ca2+-activated autophagy was monitored by fluorescent labeling of autophagosomes and western blotting assays. CSC marker expression, sphere formation, colony formation, and transwell of invasion were detected to investigate the role of SEC61G in regulating cancer-stem cell (CSC) properties.

Results

Among the SEC61 complex genes, only SEC61G upregulation is consistently associated with unfavorable progression-free interval and disease-specific survival in patients with HNSCC. Low-dose cisplatin (CDDP) treatment induced SEC61G upregulation in SCC15 and CAL27 cells. SEC61G knockdown significantly impaired CDDP-induced Ca2+ from the ER and the phosphorylation of ERK1/2 and AMPK. CDDP-induced autophagy in HNSCC cells were hampered by SEC61G shRNA, in terms of impaired autophagosome formation, lowered LC3-II/GAPDH ratio and restored p62 expression. CDDP-induced CSC properties, including CSC marker expression, sphere formation, colony formation, and invasive capabilities could be suppressed by shSEC61G and chloroquine, a specific autophagy inhibitor.

Conclusion

Findings of this study revealed the contribution of SEC61G in promoting cisplatin-induced CSC properties of HNSCC cells via promoting Ca2+-mediated autophagy.

SEC61G assists EGFR-amplified glioblastoma to evade immune elimination

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.

A novel oxidative stress-related genes signature associated with clinical prognosis and immunotherapy responses in clear cell renal cell carcinoma

Background

Oxidative stress plays a significant role in the tumorigenesis and progression of tumors. We aimed to develop a prognostic signature using oxidative stress-related genes (ORGs) to predict clinical outcome and provide light on the immunotherapy responses of clear cell renal cell carcinoma (ccRCC).

Methods

The information of ccRCC patients were collected from the TCGA and the E-MTAB-1980 datasets. Univariate Cox regression analysis and least absolute shrinkage and selection operator (LASSO) were conducted to screen out overall survival (OS)-related genes. Then, an ORGs risk signature was built by multivariate Cox regression analyses. The performance of the risk signature was evaluated with Kaplan-Meier (K-M) survival. The ssGSEA and CIBERSORT algorithms were performed to evaluate immune infiltration status. Finally, immunotherapy responses was analyzed based on expression of several immune checkpoints.

Results

A prognostic 9-gene signature with ABCB1, AGER, E2F1, FOXM1, HADH, ISG15, KCNMA1, PLG, and TEK. The patients in the high risk group had apparently poor survival (TCGA: p < 0.001; E-MTAB-1980: p < 0.001). The AUC of the signature was 0.81 at 1 year, 0.76 at 3 years, and 0.78 at 5 years in the TCGA, respectively, and was 0.8 at 1 year, 0.82 at 3 years, and 0.83 at 5 years in the E-MTAB-1980, respectively. Independent prognostic analysis proved the stable clinical prognostic value of the signature (TCGA cohort: HR = 1.188, 95% CI =1.142-1.236, p < 0.001; E-MTAB-1980 cohort: HR =1.877, 95% CI= 1.377-2.588, p < 0.001). Clinical features correlation analysis proved that patients in the high risk group were more likely to have a larger range of clinical tumor progression. The ssGSEA and CIBERSORT analysis indicated that immune infiltration status were significantly different between two risk groups. Finally, we found that patients in the high risk group tended to respond more actively to immunotherapy.

Conclusion

We developed a robust prognostic signature based on ORGs, which may contribute to predict survival and guide personalize immunotherapy of individuals with ccRCC.

E2F1‑mediated RAB34 upregulation accelerates the proliferation and inhibits the cell cycle arrest and apoptosis of acute myeloid leukemia cells

Acute myeloid leukemia (AML) is a malignant disease that is mainly arisen from myeloid stem/progenitor cells. The pathogenesis of AML is complex. Ras-related protein member RAS oncogene GTPases (RAB) 34 protein has been reported to serve an important role in the development of cancer. However, to the best of our knowledge, the role of RAB34 in AML has not been previously reported. The GEPIA database was used to predict the expression levels of RAB34 in patients with AML. Reverse transcription-quantitative PCR and western blotting were used to detect the expression of RAB34 in AML cell lines. Cell transfection with short hairpin (sh)RNAs targeting RAB34 was used to interfere with RAB34 expression. Cell Counting Kit-8 and 5-ethynyl-2'-deoxyuridine staining were used to measure cell proliferation. Flow cytometry was used to investigate cell cycle distribution and apoptosis. Western blotting was used to assess the protein expression levels of RAB34 and E2F transcription factor 1 (E2F1), and cell cycle- and apoptosis-associated proteins, including Bcl-2, Bax, CDK4, CDK8 and cyclin D1. The potential binding between E2F1 and RAB34 was then verified by luciferase reporter and chromatin immunoprecipitation assays. Subsequently, cells were co-transfected with RAB34 shRNA and the E2F1 overexpression plasmid before cell proliferation, cell cycle and apoptosis were analyzed further. The expression of RAB34 was found to be significantly increased in AML cell lines. Knocking down RAB34 expression in AML cells was found to significantly inhibit cell proliferation, induce cell cycle arrest and promote apoptosis. E2F1 activated the transcription of RAB34 and E2F1 elevation reversed the impacts of RAB34 silencing on cell proliferation, cell cycle and apoptosis in AML. Therefore, these findings suggest that E2F1-mediated RAB34 upregulation may accelerate the malignant progression of AML.

Multi-Omics Data Analysis Identifies Prognostic Biomarkers across Cancers

Combining omics data from different layers using integrative methods provides a better understanding of the biology of a complex disease such as cancer. The discovery of biomarkers related to cancer development or prognosis helps to find more effective treatment options. This study integrates multi-omics data of different cancer types with a network-based approach to explore common gene modules among different tumors by running community detection methods on the integrated network. The common modules were evaluated by several biological metrics adapted to cancer. Then, a new prognostic scoring method was developed by weighting mRNA expression, methylation, and mutation status of genes. The survival analysis pointed out statistically significant results for GNG11, CBX2, CDKN3, ARHGEF10, CLN8, SEC61G and PTDSS1 genes. The literature search reveals that the identified biomarkers are associated with the same or different types of cancers. Our method does not only identify known cancer-specific biomarker genes, but also proposes new potential biomarkers. Thus, this study provides a rationale for identifying new gene targets and expanding treatment options across cancer types.

Hsa_circ_0060467 promotes breast cancer liver metastasis by complexing with eIF4A3 and sponging miR-1205

Breast cancer (BC) is the most common cancer and the top cause of female mortality worldwide. The prognosis for patients with breast cancer liver metastasis (BCLM) remains poor. Emerging studies suggest that circular RNAs (circRNAs) are associated with the progression of BC. Exploration of circRNAs presents a promising avenue for identifying metastasis-targeting agents and improving the prognosis of patients with BCLM. Microarray and bioinformatic analyses were used to analyze differentially expressed circRNAs between three pairs of BCLM and primary BC. The roles of hsa_circ_0060467 (circMYBL2) and its target gene E2F1 in BC cells were explored by multiple functional experiments. And xenograft mouse models and hepatic metastases of BC hemi-spleen models were used to illustrate the function of circMYBL2 in vivo. The intrinsic molecular mechanism involving circMYBL2 was confirmed by bioinformatics analyses, RIP assays, CHIRP assays, luciferase reporter assays, and rescue experiments. CircMYBL2 was overexpressed in BCLM tissues and BC cells. Functionally, circMYBL2 can facilitate the proliferation and liver metastasis of BC. Mechanistically, circMYBL2 upregulated the transcription factor E2F1 by sponging miR-1205 and complexing with eukaryotic translation initiation factor 4A3 (eIF4A3) and then facilitated the epithelial-mesenchymal transition (EMT) process in BC cells. Our findings showed that circMYBL2 promoted the tumorigenesis and aggressiveness of BC through the circMYBL2/miR-1205/E2F1 and circMYBL2/eIF4A3/E2F1 axes, which may provide a novel targeted therapy for patients with BCLM.

PHF6 recruits BPTF to promote HIF-dependent pathway and progression in YAP-high breast cancer

BACKGROUND

Aberrant epigenetic remodeling events contribute to progression and metastasis of breast cancer (Bca). The specific mechanims that epigenetic factors rely on to mediate tumor aggressiveness remain unclear. We aimed to elucidate the roles of epigenetic protein PHF6 in breast tumorigenesis.

METHODS

Published datasets and tissue samples with PHF6 staining were used to investigate the clinical relevance of PHF6 in Bca. CCK-8, clony formation assays were used to assess cell growth capacity. Cell migration and invasion abilities were measured by Transwell assay. The gene mRNA and protein levels were measured by quantitative real-time PCR and western blot. Chromatin immunoprecipitation (ChIP)-qPCR assays were used to investigate transcriptional relationships among genes. The Co-immunoprecipitation (Co-IP) assay was used to validate interactions between proteins. The CRISPR/Cas9 editing technology was used to construct double HIF knockout (HIF-DKO) cells. The subcutaneous xenograft model and orthotopic implantation tumor model were used to asess in vivo tumor growth.

RESULTS

In this study, we utilized MTT assay to screen that PHF6 is required for Bca growth. PHF6 promotes Bca proliferation and migration. By analyzing The Cancer Genome Atlas breast cancer (TCGA-Bca) cohort, we found that PHF6 was significantly higher in tumor versus normal tissues. Mechanistically, PHF6 physically interacts with HIF-1α and HIF-2α to potentiate HIF-driven transcriptional events to initiate breast tumorigenesis. HIF-DKO abolished PHF6-mediated breast tumor growth, and PHF6 deficiency in turn impaired HIF transcriptional effects. Besides, hypoxia could also rely on YAP activation, but not HIF, to sustain PHF6 expressions in Bca cells. In addition, PHF6 recuits BPTF to mediate epigenetic remodeling to augment HIF transcriptional activity. Targeting PHF6 or BPTF inhibitor (AU1) is effective in mice models. Lastly, PHF6 correlated with HIF target gene expression in human breast tumors, which is an independent prognostic regulator.

CONCLUSIONS

Collectively, this study identified PHF6 as a prognostic epigenetic regulator for Bca, functioning as a HIF coactivator. The fundamental mechanisms underlying YAP/PHF6/HIF axis in breast tumors endowed novel epigenegtic targets for Bca treatment.

Towards dual function of autophagy in breast cancer: A potent regulator of tumor progression and therapy response

As a devastating disease, breast cancer has been responsible for decrease in life expectancy of females and its morbidity and mortality are high. Breast cancer is the most common tumor in females and its treatment has been based on employment of surgical resection, chemotherapy and radiotherapy. The changes in biological behavior of breast tumor relies on genomic and epigenetic mutations and depletions as well as dysregulation of molecular mechanisms that autophagy is among them. Autophagy function can be oncogenic in increasing tumorigenesis, and when it has pro-death function, it causes reduction in viability of tumor cells. The carcinogenic function of autophagy in breast tumor is an impediment towards effective therapy of patients, as it can cause drug resistance and radio-resistance. The important hallmarks of breast tumor such as glucose metabolism, proliferation, apoptosis and metastasis can be regulated by autophagy. Oncogenic autophagy can inhibit apoptosis, while it promotes stemness of breast tumor. Moreover, autophagy demonstrates interaction with tumor microenvironment components such as macrophages and its level can be regulated by anti-tumor compounds in breast tumor therapy. The reasons of considering autophagy in breast cancer therapy is its pleiotropic function, dual role (pro-survival and pro-death) and crosstalk with important molecular mechanisms such as apoptosis. Moreover, current review provides a pre-clinical and clinical evaluation of autophagy in breast tumor.

Increased response to TPF chemotherapy promotes immune escape in hypopharyngeal squamous cell carcinoma

Background: There is an urgent need to identify which patients would benefit from TPF chemotherapy in hypopharyngeal squamous cell carcinoma (HPSCC) and to explore new combinations to improve the treatment effect. Materials and methods: Gene-expression profiles in 15 TPF-sensitive patients were compared to 13 resistant patients. Immunohistochemistry (IHC) was performed to detect CD8⁺ T cells in 28 samples. Patient-Derived Tumor Xenograft (PDX) model and IHC were used to verify markers that optimize treatment for HPSCC. Results: Through RNA sequencing 188 genes were up-regulated in TPF chemotherapy-resistant (CR) tissues were involved in T cell activation, while 60 down-regulated genes were involved in glycolysis. Gene set enrichment analysis (GSEA) showed that chemotherapy-sensitive (CS) group upregulation of the pathways of glycolysis, while immune response was downregulated. CIBERSORT, MCP-counter, and IHC proved that most immune cells including CD8⁺ T cells in the CR significantly higher than that in CS group. Among the 16 up-regulated genes in CS had close associations, the most significant negative correlation between the gene level and CD8⁺ T cells existed in SEC61G. SEC61G was related to glycolysis, which was transcriptionally regulated by E2F1, and participated in antigen degradation through ubiquitin-dependent protein catabolic process. Palbociclib, combined with Cetuximab decreased the tumor burden and significantly suppressed the expression of E2F1 and SEC61G while activating MHC-I in PDX model. Conclusion: Enhanced glycolysis promoted immune escape, but increased response to TPF chemotherapy. SEC61G was the center of the molecular network and targeting the E2F1/SEC61G pathway increased the expression level of MHC-I.

T cell exhaustion assessment algorism in tumor microenvironment predicted clinical outcomes and immunotherapy effects in glioma

Despite the recent increase in the use of immune checkpoint blockade (ICB), no ICB medications have been approved or are undergoing large-scale clinical trials for glioma. T cells, the main mediators of adaptive immunity, are important components of the tumor immune microenvironment. Depletion of T cells in tumors plays a key role in assessing the sensitivity of patients to immunotherapy. In this study, the bioinformatics approach was applied to construct T cell depletion-related risk assessment to investigate the impact of T cell depletion on prognosis and ICB response in glioma patients. The Cancer Genome Atlas (TCGA) and GSE108474 glioma cohorts and IMvigor210 immunotherapy datasets were collected, including complete mRNA expression profiles and clinical information. We used cell lines to verify the gene expression and the R 3.6.3 tool and GraphPad for bioinformatics analysis and mapping. T cell depletion in glioma patients displayed significant heterogeneity. The T cell depletion-related prognostic model was developed based on seven prognostic genes (HSPB1, HOXD10, HOXA5, SEC61G, H19, ANXA2P2, HOXC10) in glioma. The overall survival of patients with a high TEXScore was significantly lower than that of patients with a low TEXScore. In addition, high TEXScore scores were followed by intense immune responses and a more complex tumor immune microenvironment. The “hot tumors” were predominantly enriched in the high-risk group, which patients expressed high levels of suppressive immune checkpoints, such as PD1, PD-L1, and TIM3. However, patients with a low TEXScore had a more significant clinical response to immunotherapy. In addition, HSPB1 expression was higher in the U251 cells than in the normal HEB cells. In conclusion, the TEXScore related to T cell exhaustion combined with other pathological profiles can effectively assess the clinical status of glioma patients. The TEXScore constructed in this study enables the effective assessment of the immunotherapy response of glioma patients and provides therapeutic possibilities.

E2F1-initiated transcription of PRSS22 promotes breast cancer metastasis by cleaving ANXA1 and activating FPR2/ERK signaling pathway

Breast cancer (BC) is the most common malignant tumor in women worldwide. Metastasis is the main cause of BC-related death. The specific mechanism underlying BC metastasis remains obscure. Recently, PRSS22 was discovered to be involved in tumor development, however, its detailed biological function and regulatory mechanism in BC are unclear. Here, we characterized that PRSS22 expression is upregulated in BC tissues compared with non-tumorous breast tissues. Dual luciferase assays, bioinformatics analyses and chromatin immunoprecipitation (ChIP) assays indicated that transcription factor E2F1 directly binds to the PRSS22 promoter region and activates its transcription. Functionally, upregulation of PRSS22 promoted invasion and metastasis of BC cells in vitro and in vivo, whereas knockdown of PRSS22 inhibited its function. Mechanistically, the combination of PRSS22 and ANXA1 protein in BC cells was first screened by protein mass spectrometry analysis, and then confirmed by co-immunoprecipitation (Co-IP) and western blot assays. Co-overexpression of PRSS22 and ANXA1 could promote BC cell migration and invasion. We further demonstrated that PRSS22 promotes the cleavage of ANXA1 and in turn generates an N-terminal peptide, which initiates the FPR2/ERK signaling axis to increase BC aggressiveness.

CEBPB regulates the bile acid receptor FXR to accelerate colon cancer progression by modulating aerobic glycolysis

BACKGROUND

Aerobic glycolysis is a main characteristic of tumors, and inhibited glycolysis impedes the tumor development. Farnesoid X Receptor (FXR) mainly regulates bile acid metabolism. In this research, we mainly investigated whether FXR was involved in the regulation of glycolysis in colon cancer.

METHODS

The differential expression analysis was performed on FXR and Enhancer Binding Protein Beta (CEBPB) data in colon cancer downloaded from The Cancer Genome Atlas (TCGA) database. Western blot and qRT-PCR were used to detect the expression levels of CEBPB and FXR. The upstream gene of FXR was predicted through bioinformatic analysis. ChIP and dual luciferease assays were performed to confirm the targeted relationship between CEBPB and FXR. Gene Set Enrichment Analysis (GSEA) was performed on FXR. Finally, the glycolysis capabilities of cells in each treatment group were detected. CCK-8, colony formation assay and flow cytometry were performed to test proliferation and apoptosis of colon cancer cells.

RESULTS

FXR was lowly expressed at the cell level in colon cancer. In vitro assays verified the antitumor effect of FXR on colon cancer. ChIP and dual luciferase assays verified that transcription factor CEBPB bound with the promotor region of FXR, and negatively regulated the expression of FXR. Cell function assays proved that silenced expression of FXR promoted glycolysis, which promoted the development of colon cancer cells.

CONCLUSION

The study on FXR-regulated glycolysis of colon cancer cells helps us to further understand the molecular mechanism by which FXR regulated the development of colon cancer cells.

E2F1 promotes Warburg effect and cancer progression via upregulating ENO2 expression in Ewing sarcoma

Altered glucose metabolism is an important characteristic of cancer cells, which is referred to as Warburg effect or aerobic glycolysis. Ewing sarcoma (EWS) is a highly malignant tumor that occurs in children and adolescents. However, the functions of aerobic glycolysis in EWS remain to be elucidated. The present study identified a transcription factor, E2F transcription factor 1 (E2F1), as a new regulator of cancer the aerobic glycolysis and progression in EWS. The present study showed that E2F1 modulated aerobic glycolysis in EWS cells by effecting glucose uptake, lactate production and ATP generation. Altered E2F1 expression increased or decreased cell viability and invasion in EWS. Mechanistically, the results demonstrated that E2F1 may promote the Warburg effect and cancer progression in EWS via upregulating enolase 2 expression. Generally, these findings indicated that E2F1 involvement in the progression of EWS and could serve as a clinical therapeutic target in EWS.

KIAA0101 knockdown inhibits glioma progression and glycolysis by inactivating the PI3K/AKT/mTOR pathway

KIAA0101, a proliferating cell nuclear antigen (PCNA)-associated factor, is reported to be overexpressed and identified as an oncogene in several human malignancies. The purpose of this study is to determine the function and possible mechanism of KIAA0101 in glioma progression. KIAA0101 expression in glioma patients was analyzed by GSE50161 and GEPIA datasets. Kaplan-Meier survival analysis was used to evaluate the survival distributions. KIAA0101 expression in glioma cells were detected by qRT-PCR and western blot analyses. The function of KIAA0101 was investigated using MTT, flow cytometry, caspase-3 activity, and Transwell assays. Additionally, glycolytic flux was determined by measuring extracellular acidification rate (ECAR), glucose consumption, lactate production, and adenosine triphosphate (ATP) level. The changes of phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway were detected by western blot analysis. Results showed that KIAA0101 was upregulated in glioma tissues and cells. High KIAA0101 expression predicted a poor prognosis in glioma patients. KIAA0101 depletion impeded cell proliferation, migration, and invasion and triggered apoptosis in glioma cells. KIAA0101 silencing reduced the ECAR, glucose consumption, lactate production, and ATP level in glioma cells, suggesting that KIAA0101 knockdown inhibited glycolysis in glioma cells. Mechanistically, KIAA0101 knockdown inhibited the PI3K/AKT/mTOR pathway. In conclusion, KIAA0101 silencing inhibited glioma progression and glycolysis by inactivating the PI3K/AKT/mTOR pathway.

FGF14-AS2 accelerates tumorigenesis in glioma by forming a feedback loop with miR-320a/E2F1 axis

Glioma is the most common primary tumour in the central nervous system in adults, and at present, there is no effective treatment to cure this malignancy. Long noncoding RNAs (lncRNAs) are closely related to tumour progression and have attracted increasing attention in tumour research. However, the role of lncRNA FGF14-AS2 in glioma tumorigenesis has not been determined. In the present study, we found that FGF14-AS2 expression was significantly elevated in glioma tissues and was associated with poor survival in glioma patients. Silencing FGF14-AS2 inhibited the proliferation, migration and invasion ability of glioma cells. In vivo assay showed that silencing FGF14-AS2 led to inhibition of tumour growth. In addition, FGF14-AS2 was observed to promote glioma progression via the miR-320a/E2F1 axis. Moreover, E2F1 could bind to the promoter region of FGF14-AS2, thereby enhancing FGF14-AS2 expression. In conclusion, FGF14-AS2 could accelerate tumorigenesis of glioma by forming a feedback loop with the miR-320a/E2F1 axis which suggested that FGF14-AS2 could serve as a therapeutic target for glioma.