Anoikis resistant gastric cancer cells promote angiogenesis and peritoneal metastasis through C/EBPβ-mediated PDGFB autocrine and paracrine signaling

Extracellular Vesicles Containing circMYBL1 Induce CD44 in Adenoid Cystic Carcinoma Cells and Pulmonary Endothelial Cells to Promote Lung Metastasis

Adenoid cystic carcinoma (ACC) is a rare malignant epithelial neoplasm that arises in secretory glands and commonly metastasizes to the lungs. MYBL1 is frequently overexpressed in ACC and has been suggested to be a driver of the disease. In this study, we identified a circular RNA (circRNA) derived from MYBL1 pre-mRNA that was accompanied by the overexpression of MYBL1 in ACC. Overexpression of circMYBL1 was correlated with increased lung metastasis and poor overall survival in patients with ACC. Ectopic circMYBL1 overexpression promoted malignant phenotypes and lung metastasis of ACC cells. Mechanistically, circMYBL1 formed a circRNA-protein complex with CCAAT enhancer-binding protein β (CEBPB), which inhibited ubiquitin-mediated degradation and promoted nuclear translocation of CEBPB. In the nucleus, circMYBL1 increased the binding of CEBPB to the CD44 promoter region and enhanced its transcription. In addition, circMYBL1 was enriched in small extracellular vesicles (sEV) isolated from the plasma of patients with ACC. Treatment with sEVs containing circMYBL1 in sEVs enhanced prometastatic phenotypes of ACC cells, elevated the expression of CD44 in human pulmonary microvascular endothelial cells (HPMEC), and enhanced the adhesion between HPMECs and ACC cells. Moreover, circMYBL1 encapsulated in sEVs increased the arrest of circulating ACC cells in the lung and enhanced lung metastatic burden. These data suggest that circMYBL1 is a tumor-promoting circRNA that could serve as a potential biomarker and therapeutic target for ACC. Significance: circMYBL1 stabilizes CEBPB and upregulates CD44 to promote adhesion between cancer cells and endothelial cells and enables lung metastasis of adenoid cystic carcinoma, suggesting that inhibition of this axis could improve patient outcomes.

DDR1 Drives Malignant Progression of Gastric Cancer by Suppressing HIF-1α Ubiquitination and Degradation

The extracellular matrix (ECM) has been demonstrated to be dysregulated and crucial for malignant progression in gastric cancer (GC), but the mechanism is not well understood. Here, that discoidin domain receptor 1 (DDR1), a principal ECM receptor, is recognized as a key driver of GC progression is reported. Mechanistically, DDR1 directly interacts with the PAS domain of hypoxia-inducible factor-1α (HIF-1α), suppresses its ubiquitination and subsequently strengthens its transcriptional regulation of angiogenesis. Additionally, DDR1 upregulation in GC cells promotes actin cytoskeleton reorganization by activating HIF-1α/ Ras Homolog Family Member A (RhoA)/Rho-associated protein kinase 1 (ROCK1) signaling, which in turn enhances the metastatic capacity. Pharmacological inhibition of DDR1 suppresses GC progression and angiogenesis in patient-derived xenograft (PDX) and organoid models. Taken together, this work first indicates the effects of the DDR1-HIF-1α axis on GC progression and reveals the related mechanisms, providing experimental evidence for DDR1 as a therapeutic target for GC.

Lopinavir enhances anoikis by remodeling autophagy in a circRNA-dependent manner

Macroautophagy/autophagy-mediated anoikis resistance is crucial for tumor metastasis. As a key autophagy-related protein, ATG4B has been demonstrated to be a prospective anti-tumor target. However, the existing ATG4B inhibitors are still far from clinical application, especially for tumor metastasis. In this study, we identified a novel circRNA, circSPECC1, that interacted with ATG4B. CircSPECC1 facilitated liquid-liquid phase separation of ATG4B, which boosted the ubiquitination and degradation of ATG4B in gastric cancer (GC) cells. Thus, pharmacological addition of circSPECC1 may serve as an innovative approach to suppress autophagy by targeting ATG4B. Specifically, the circSPECC1 underwent significant m6A modification in GC cells and was subsequently recognized and suppressed by the m6A reader protein ELAVL1/HuR. The activation of the ELAVL1-circSPECC1-ATG4B pathway was demonstrated to mediate anoikis resistance in GC cells. Moreover, we also verified that the above pathway was closely related to metastasis in tissues from GC patients. Furthermore, we determined that the FDA-approved compound lopinavir efficiently enhanced anoikis and prevented metastasis by eliminating repression of ELAVL1 on circSPECC1. In summary, this study provides novel insights into ATG4B-mediated autophagy and introduces a viable clinical inhibitor of autophagy, which may be beneficial for the treatment of GC with metastasis.

Targeting anoikis resistance as a strategy for cancer therapy

Anoikis, known as matrix detachment-induced apoptosis or detachment-induced cell death, is crucial for tissue development and homeostasis. Cancer cells develop means to evade anoikis, e.g. anoikis resistance, thereby allowing for cells to survive under anchorage-independent conditions. Uncovering the mechanisms of anoikis resistance will provide details about cancer metastasis, and potential strategies against cancer cell dissemination and metastasis. Here, we summarize the principal elements and core molecular mechanisms of anoikis and anoikis resistance. We discuss the latest progress of how anoikis and anoikis resistance are regulated in cancers. Furthermore, we summarize emerging data on selective compounds and nanomedicines, explaining how inhibiting anoikis resistance can serve as a meaningful treatment modality against cancers. Finally, we discuss the key limitations of this therapeutic paradigm and possible strategies to overcome them. In this review, we suggest that pharmacological modulation of anoikis and anoikis resistance by bioactive compounds could surmount anoikis resistance, highlighting a promising therapeutic regimen that could be used to overcome anoikis resistance in cancers.

C/EBPβ-Lin28a positive feedback loop triggered by C/EBPβ hypomethylation enhances the proliferation and migration of vascular smooth muscle cells in restenosis

BACKGROUND

The main cause of restenosis after percutaneous transluminal angioplasty (PTA) is the excessive proliferation and migration of vascular smooth muscle cells (VSMCs). Lin28a has been reported to play critical regulatory roles in this process. However, whether CCAAT/enhancer-binding proteins β (C/EBPβ) binds to the Lin28a promoter and drives the progression of restenosis has not been clarified. Therefore, in the present study, we aim to clarify the role of C/EBPβ-Lin28a axis in restenosis.

METHODS

Restenosis and atherosclerosis rat models of type 2 diabetes (n  =  20, for each group) were established by subjecting to PTA. Subsequently, the difference in DNA methylation status and expression of C/EBPβ between the two groups were assessed. EdU, Transwell, and rescue assays were performed to assess the effect of C/EBPβ on the proliferation and migration of VSMCs. DNA methylation status was further assessed using Methyltarget sequencing. The interaction between Lin28a and ten-eleven translocation 1 (TET1) was analysed using co-immunoprecipitation (Co-IP) assay. Student's t-test and one-way analysis of variance were used for statistical analysis.

RESULTS

C/EBPβ expression was upregulated and accompanied by hypomethylation of its promoter in restenosis when compared with atherosclerosis. In vitroC/EBPβ overexpression facilitated the proliferation and migration of VSMCs and was associated with increased Lin28a expression. Conversely, C/EBPβ knockdown resulted in the opposite effects. Chromatin immunoprecipitation assays further demonstrated that C/EBPβ could directly bind to Lin28a promoter. Increased C/EBPβ expression and enhanced proliferation and migration of VSMCs were observed after decitabine treatment. Further, mechanical stretch promoted C/EBPβ and Lin28a expression accompanied by C/EBPβ hypomethylation. Additionally, Lin28a overexpression reduced C/EBPβ methylation via recruiting TET1 and enhanced C/EBPβ-mediated proliferation and migration of VSMCs. The opposite was noted in Lin28a knockdown cells.

CONCLUSION

Our findings suggest that the C/EBPβ-Lin28a axis is a driver of restenosis progression, and presents a promising therapeutic target for restenosis.

Choline metabolism reprogramming mediates an immunosuppressive microenvironment in non-small cell lung cancer (NSCLC) by promoting tumor-associated macrophage functional polarization and endothelial cell proliferation

INTRODUCTION

Lung cancer is a prevalent malignancy globally, and immunotherapy has revolutionized its treatment. However, resistance to immunotherapy remains a challenge. Abnormal cholinesterase (ChE) activity and choline metabolism are associated with tumor oncogenesis, progression, and poor prognosis in multiple cancers. Yet, the precise mechanism underlying the relationship between ChE, choline metabolism and tumor immune microenvironment in lung cancer, and the response and resistance of immunotherapy still unclear.

METHODS

Firstly, 277 advanced non-small cell lung cancer (NSCLC) patients receiving first-line immunotherapy in Sun Yat-sen University Cancer Center were enrolled in the study. Pretreatment and the alteration of ChE after 2 courses of immunotherapy and survival outcomes were collected. Kaplan-Meier survival and cox regression analysis were performed, and nomogram was conducted to identify the prognostic and predicted values. Secondly, choline metabolism-related genes were screened using Cox regression, and a prognostic model was constructed. Functional enrichment analysis and immune microenvironment analysis were also conducted. Lastly, to gain further insights into potential mechanisms, single-cell analysis was performed.

RESULTS

Firstly, baseline high level ChE and the elevation of ChE after immunotherapy were significantly associated with better survival outcomes for advanced NSCLC. Constructed nomogram based on the significant variables from the multivariate Cox analysis performed well in discrimination and calibration. Secondly, 4 choline metabolism-related genes (MTHFD1, PDGFB, PIK3R3, CHKB) were screened and developed a risk signature that was found to be related to a poorer prognosis. Further analysis revealed that the choline metabolism-related genes signature was associated with immunosuppressive tumor microenvironment, immune escape and metabolic reprogramming. scRNA-seq showed that MTHFD1 was specifically distributed in tumor-associated macrophages (TAMs), mediating the differentiation and immunosuppressive functions of macrophages, which may potentially impact endothelial cell proliferation and tumor angiogenesis.

CONCLUSION

Our study highlights the discovery of ChE as a prognostic marker in advanced NSCLC, suggesting its potential for identifying patients who may benefit from immunotherapy. Additionally, we developed a prognostic signature based on choline metabolism-related genes, revealing the correlation with the immunosuppressive microenvironment and uncovering the role of MTHFD1 in macrophage differentiation and endothelial cell proliferation, providing insights into the intricate workings of choline metabolism in NSCLC pathogenesis.

Anoikis patterns via machine learning strategy and experimental verification exhibit distinct prognostic and immune landscapes in melanoma

BACKGROUND

Anoikis is a cell death programmed to eliminate dysfunctional or damaged cells induced by detachment from the extracellular matrix. Utilizing an anoikis-based risk stratification is anticipated to understand melanoma's prognostic and immune landscapes comprehensively.

METHODS

Differential expression genes (DEGs) were analyzed between melanoma and normal skin tissues in The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression data sets. Next, least absolute shrinkage and selection operator, support vector machine-recursive feature elimination algorithm, and univariate and multivariate Cox analyses on the 308 DEGs were performed to build the prognostic signature in the TCGA-melanoma data set. Finally, the signature was validated in GSE65904 and GSE22155 data sets. NOTCH3, PIK3R2, and SOD2 were validated in our clinical samples by immunohistochemistry.

RESULTS

The prognostic model for melanoma patients was developed utilizing ten hub anoikis-related genes. The overall survival (OS) of patients in the high-risk subgroup, which was classified by the optimal cutoff value, was remarkably shorter in the TCGA-melanoma, GSE65904, and GSE22155 data sets. Low-risk patients exhibited low immune cell infiltration and high expression of immunophenoscores and immune checkpoints. They also demonstrated increased sensitivity to various drugs, including dasatinib and dabrafenib. NOTCH3, PIK3R2, and SOD2 were notably associated with OS by univariate Cox analysis in the GSE65904 data set. The clinical melanoma samples showed remarkably higher protein expressions of NOTCH3 (P = 0.003) and PIK3R2 (P = 0.009) than the para-melanoma samples, while the SOD2 protein expression remained unchanged.

CONCLUSIONS

In this study, we successfully established a prognostic anoikis-connected signature using machine learning. This model may aid in evaluating patient prognosis, clinical characteristics, and immune treatment modalities for melanoma.

Clinical value of molecular subtypes identification based on anoikis-related lncRNAs in castration-resistant prostate cancer

BACKGROUND

Anoikis is a distinctive type of apoptosis. It is involved in tumor progression and metastasis. But its function in castration-resistant prostate cancer (CRPC) remains veiled. We aimed to develop a prognostic indicator based on anoikis-related long non-coding RNAs (arlncRNAs) and to investigate their biological function in CRPC.

MATERIAL AND METHOD

Differentially expressed anoikis-related genes were extracted from two CRPC datasets, GSE51873, and GSE78201. Four lncRNAs associated with the anoikis-related genes were selected. A risk model based on these lncRNAs was developed and validated in The Cancer Genome Atlas (TCGA) and the Memorial Sloan-Kettering Cancer Center (MSKCC) prostate cancer cohorts. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, immune infiltration, immune checkpoints expression, and drug susceptibility were performed based on the model. To identify the biofunction of anoikis-related lncRNA, CCK-8 assays, colony formation assays, and flow cytometry were used.

RESULT

Twenty-nine anoikis-related genes were differentially expressed in the CRPC datasets. And 36 prognostic arlncRNAs were selected for the LASSO Cox analysis. Patients were subsequently classified into two subtypes by constructing an anoikis-related lncRNA based prognostic index (ARPI). The accuracy of this index was validated. KEGG enrichment analysis revealed that the high-ARPI group was enriched in cancer-related and immune-related pathways. Immune infiltration analysis has indicated a positive association between high-ARPI groups and increased immune infiltration. Fulvestrant, OSI-027, Lapatinib, Dabrafenib, and Palbociclib were identified as potential sensitive drugs for high-ARPI patients. In vitro experiments exhibited that silencing LINC01138 dampened the proliferation, migration and enzalutamide resistance in CRPC. Furthermore, it stimulated apoptosis and inhibited the eithelial-mesenchymal transition process.

CONCLUSION

Four arlncRNAs were identified and a risk model was established to predict the prognosis of patients with prostate cancer. Immune infiltration and drug susceptibility analysis revealed a potential therapeutic strategy for patients with castration-resistant prostate cancer.

Adipose-derived stem cells promote glycolysis and peritoneal metastasis via TGF-β1/SMAD3/ANGPTL4 axis in colorectal cancer

Peritoneal metastasis, the third most common metastasis in colorectal cancer (CRC), has a poor prognosis for the rapid progression and limited therapeutic strategy. However, the molecular characteristics and pathogenesis of CRC peritoneal metastasis are poorly understood. Here, we aimed to elucidate the action and mechanism of adipose-derived stem cells (ADSCs), a prominent component of the peritoneal microenvironment, in CRC peritoneal metastasis formation. Database analysis indicated that ADSCs infiltration was increased in CRC peritoneal metastases, and high expression levels of ADSCs marker genes predicted a poor prognosis. Then we investigated the effect of ADSCs on CRC cells in vitro and in vivo. The results revealed that CRC cells co-cultured with ADSCs exhibited stronger metastatic property and anoikis resistance, and ADSCs boosted the intraperitoneal seeding of CRC cells. Furthermore, RNA sequencing was carried out to identify the key target gene, angiopoietin like 4 (ANGPTL4), which was upregulated in CRC specimens, especially in peritoneal metastases. Mechanistically, TGF-β1 secreted by ADSCs activated SMAD3 in CRC cells, and chromatin immunoprecipitation assay showed that SMAD3 facilitated ANGPTL4 transcription by directly binding to ANGPTL4 promoter. The ANGPTL4 upregulation was essential for ADSCs to promote glycolysis and anoikis resistance in CRC. Importantly, simultaneously targeting TGF-β signaling and ANGPTL4 efficiently reduced intraperitoneal seeding in vivo. In conclusion, this study indicates that tumor-infiltrating ADSCs promote glycolysis and anoikis resistance in CRC cells and ultimately facilitate peritoneal metastasis via the TGF-β1/SMAD3/ANGPTL4 axis. The dual-targeting of TGF-β signaling and ANGPTL4 may be a feasible therapeutic strategy for CRC peritoneal metastasis.

Cross-talk between gastric cancer and hepatic stellate cells promotes invadopodia formation during liver metastasis

In gastric cancer (GC), the liver is a common organ for distant metastasis, and patients with gastric cancer with liver metastasis (GCLM) generally have poor prognosis. The mechanism of GCLM is unclear. Invadopodia are special membrane protrusions formed by tumor cells that can degrade the basement membrane and ECM. Herein, we investigated the role of invadopodia in GCLM. We found that the levels of invadopodia-associated proteins were significantly higher in liver metastasis than in the primary tumors of patients with GCLM. Furthermore, GC cells could activate hepatic stellate cells (HSCs) within the tumor microenvironment of liver metastases through the secretion of platelet-derived growth factor subunit B (PDGFB). Activated HSCs secreted hepatocyte growth factor (HGF), which activated the MET proto-oncogene, MET receptor of GC cells, thereby promoting invadopodia formation through the PI3K/AKT pathway and subsequently enhancing the invasion and metastasis of GC cells. Therefore, cross-talk between GC cells and HSCs by PDGFB/platelet derived growth factor receptor beta (PDGFRβ) and the HGF/MET axis might represent potential therapeutic targets to treat GCLM.

ITGBL1 promotes anoikis resistance and metastasis in human gastric cancer via the AKT/FBLN2 axis

The resistance to anoikis plays a critical role in the metastatic progression of various types of malignancies, including gastric cancer (GC). Nevertheless, the precise mechanism behind anoikis resistance is not fully understood. Here, our primary focus was to examine the function and underlying molecular mechanism of Integrin beta-like 1 (ITGBL1) in the modulation of anoikis resistance and metastasis in GC. The findings of our investigation have demonstrated that the overexpression of ITGBL1 significantly augmented the resistance of GC cells to anoikis and promoted their metastatic potential, while knockdown of ITGBL1 had a suppressive effect on both cellular processes in vitro and in vivo. Mechanistically, we proved that ITGBL1 has a role in enhancing the resistance of GC cells to anoikis and promoting metastasis through the AKT/Fibulin-2 (FBLN2) axis. The inhibition of AKT/FBLN2 signalling was able to reverse the impact of ITGBL1 on the resistance of GC cells to anoikis and their metastatic capability. Moreover, the expression levels of ITGBL1 were found to be significantly elevated in the cancerous tissues of patients diagnosed with GC, and there was a strong correlation observed between high expression levels of ITGBL1 and worse prognosis among individuals diagnosed with GC. Significantly, it was revealed that within our cohort of GC patients, individuals exhibiting elevated ITGBL1 expression and diminished FBLN2 expression experienced the worst prognosis. In conclusion, the findings of our study indicate that ITGBL1 may serve as a possible modulator of resistance to anoikis and the metastatic process in GC.

NAT10/CEBPB/vimentin signalling axis promotes adenoid cystic carcinoma malignant phenotypes in vitro

OBJECTIVE

To explore the biological function and mechanisms of CEBPB and NAT10-mediated N4-acetylcytidine (ac4c) modification in salivary adenoid cystic carcinoma (SACC).

MATERIALS AND METHODS

CEBPB and NAT10 were knocked down in SACC-LM cells by siRNA transfection and overexpressed in SACC-83 cells by plasmid transfection. Malignant phenotypes were evaluated using CCK-8, Transwell migration and colony formation assays. Real-time PCR, western blotting, ChIP and acRIP were used to investigate the molecular mechanisms involved.

RESULTS

We found that CEBPB was highly expressed in SACC tissues and correlated with lung metastasis and unfavourable prognosis. Gain- and loss-of-function experiments revealed that CEBPB promoted SACC malignant phenotypes. Mechanistically, CEBPB exerted its oncogenic effect by binding to the vimentin gene promoter region to enhance its expression. Moreover, NAT10-mediated ac4c modification led to stabilization and overexpression of CEBPB in SACC cells. We also found that NAT10, the only known human enzyme responsible for ac4C modification, promoted SACC cell migration, proliferation and colony formation. Moreover, CEBPB overexpression restored the inhibitory effect of NAT10 knockdown on malignant phenotypes.

CONCLUSIONS

Our study reveals the critical role of the newly identified NAT10/CEBPB/vimentin axis in SACC malignant progression, and the findings may be applied to improve treatment for SACC.

Prognostic significance and relationship of SMAD3 phospho-isoforms and VEGFR-1 in gastric cancer: A clinicopathological study

BACKGROUND

The TGF-β/SMAD3 and VEGFR-1 signaling pathways play important roles in gastric cancer metastasis. SMAD3 phosphorylation is a crucial prognostic marker in gastric cancer.

AIM

To determine the prognostic value and relationship of SMAD3 phospho-isoforms and VEGFR-1 in gastric cancer.

METHODS

This was a single-center observational study which enrolled 98 gastric cancer patients and 82 adjacent normal gastric tissues from patients aged 32-84 years (median age 65) between July 2006 and April 2007. Patients were followed up until death or the study ended (median follow-up duration of 28.5 mo). The samples were used to generate tissue microarrays (TMAs) for immunohistochemical (IHC) staining. The expressions of TGF-β1, pSMAD3C(S423/425), pSMAD3L(S204), and VEGFR-1 in gastric cancer (GC) tumor tissue and normal tissue were measured by IHC staining using TMAs obtained from 98 GC patients. Prognosis and survival information of the patients was recorded by Outdo Biotech from May 2007 to July 2015. The relationship between TGF-β1, pSMAD3C(S423/425), pSMAD3L(S204), and VEGFR-1 protein expression levels was analyzed using Pearson's correlation coefficient. The relationship between protein expression levels and clinicopathological parameters was analyzed using the Chi-squared test. A survival curve was generated using the Kaplan-Meier survival analysis.

RESULTS

TGFβ-1 and VEGFR-1 expression was significantly upregulated in gastric cancer tissue compared to adjacent non-cancerous tissue. The positive expression of phosphorylated isoforms of Smad3 varied depending on the phosphorylation site [pSMAD3C(S423/425): 51.0% and pSMAD3L(S204): 31.6%]. High expression of pSMAD3L(S204) was significantly correlated with larger tumors (P = 0.038) and later N stages (P = 0.035). Additionally, high expression of VEGFR-1 was closely correlated with tumor size (P = 0.015) and pathological grading (P = 0.013). High expression of both pSMAD3L(S204) and VEGFR-1 was associated with unfavorable outcomes in terms of overall survival (OS). Multivariate analysis indicated that high expression of pSMAD3L(S204) and VEGFR-1 were independent risk factors for prognosis in GC patients. VEGFR-1 protein expression was correlated with TGF-β1 (r = 0.220, P = 0.029), pSMAD3C(S423/425) (r = 0.302, P = 0.002), and pSMAD3L(S204) (r = 0.201, P = 0.047), respectively. Simultaneous overexpression of pSMAD3L(S204) and VEGFR-1 was associated with poor OS in gastric cancer patients.

CONCLUSION

Co-upregulation of pSMAD3L(S204) and VEGFR-1 can serve as a predictive marker for poor gastric cancer prognosis, and pSMAD3L(204) may be involved in enhanced gastric cancer metastasis in a VEGFR-1-dependent manner.

Hypoxia Modulates Radiosensitivity and Response to Different Radiation Qualities in A549 Non-Small Cell Lung Cancer (NSCLC) Cells

Hypoxia-induced radioresistance reduces the efficacy of radiotherapy for solid malignancies, including non-small cell lung cancer (NSCLC). Cellular hypoxia can confer radioresistance through cellular and tumor micro-environment adaptations. Until recently, studies evaluating radioresistance secondary to hypoxia were designed to maintain cellular hypoxia only before and during irradiation, while any handling of post-irradiated cells was carried out in standard oxic conditions due to the unavailability of hypoxia workstations. This limited the possibility of simulating in vivo or clinical conditions in vitro. The presence of molecular oxygen is more important for the radiotoxicity of low-linear energy transfer (LET) radiation (e.g., X-rays) than that of high-LET carbon (12C) ions. The mechanisms responsible for 12C ions' potential to overcome hypoxia-induced radioresistance are currently not fully understood. Therefore, the radioresistance of hypoxic A549 NSCLC cells following exposure to X-rays or 12C ions was investigated along with cell cycle progression and gene expression by maintaining hypoxia before, during and after irradiation. A549 cells were incubated under normoxia (20% O2) or hypoxia (1% O2) for 48 h and then irradiated with X-rays (200 kV) or 12C ions (35 MeV/n, LET ~75 keV/µm). Cell survival was evaluated using colony-forming ability (CFA) assays immediately or 24 h after irradiation (late plating). DNA double-strand breaks (DSBs) were analyzed using γH2AX immunofluorescence microscopy. Cell cycle progression was determined by flow cytometry of 4',6-diamidino-2-phenylindole-stained cells. The global transcription profile post-irradiation was evaluated by RNA sequencing. When hypoxia was maintained before, during and after irradiation, hypoxia-induced radioresistance was observed only in late plating CFA experiments. The killing efficiency of 12C ions was much higher than that of X-rays. Cell survival under hypoxia was affected more strongly by the timepoint of plating in the case of X-rays compared to 12C ions. Cell cycle arrest following irradiation under hypoxia was less pronounced but more prolonged. DSB induction and resolution following irradiation were not significantly different under normoxia and hypoxia. Gene expression response to irradiation primarily comprised cell cycle regulation for both radiation qualities and oxygen conditions. Several PI3K target genes involved in cell migration and cell motility were differentially upregulated in hypoxic cells. Hypoxia-induced radioresistance may be linked to altered cell cycle response to irradiation and PI3K-mediated changes in cell motility and migration in A549 cells rather than less DNA damage or faster repair.

Deciphering the significance of anoikis in bladder cancer and systematic analysis of S100A7 as a potential therapeutic target

BACKGROUND

Bladder cancer is an epidemic and life-threating urologic carcinoma. Anoikis is a unusual type of programmed cell death which plays a vital role in tumor survival, invasion and metastasis. Nevertheless, the relationship between anoikis and bladder cancer has not been understood thoroughly.

METHODS

We downloaded the transcriptome and clinical information of BLCA patients from TCGA and GEO databases. Then, we analyzed different expression of anoikis-related genes and established a prognostic model based on TCGA database by univariate Cox regression, lasso regression, and multivariate Cox regression. Then the Kaplan-Meier survival analysis and receiver operating characteristic (ROC) curves were performed. GEO database was used for external validation. BLCA patients in TCGA database were divided into two subgroups by non-negative matrix factorization (NMF) classification. Survival analysis, different gene expression, immune cell infiltration and drug sensitivity were calculated. Finally, we verified the function of S100A7 in two BLCA cell lines.

RESULTS

We developed a prognostic risk model based on three anoikis-related genes including TPM1, RAC3 and S100A7. The overall survival of BLCA patients in low-risk groups was significantly better than high-risk groups in training sets, test sets and external validation sets. Subsequently, the checkpoint and immune cell infiltration had significant difference between two groups. Then we identified two subtypes (CA and CB) through NMF analysis and found CA had better OS and PFS than CB. Besides, the accuracy of risk model was verified by ROC analysis. Finally, we identified that knocking down S100A7 gene expression restrained the proliferation and invasion of bladder cancer cells.

CONCLUSION

We established and validated a bladder cancer prognostic model consisting of three genes, which can effectively evaluate the prognosis of bladder cancer patients. Additionally, through cellular experiments, we demonstrated the significant role of S100A7 in the metastasis and invasion of bladder cancer, suggesting its potential as a novel target for future treatments.

ESM1 Interacts with c-Met to Promote Gastric Cancer Peritoneal Metastasis by Inducing Angiogenesis

The peritoneum is the most common metastatic site of advanced gastric cancer and is associated with extremely poor prognosis. Endothelial-specific molecule 1 (ESM1) was found to be significantly associated with gastric cancer peritoneal metastasis (GCPM); however, the biological functions and molecular mechanisms of ESM1 in regulating GCPM remain unclear. Herein, we demonstrated that ESM1 expression was significantly upregulated in gastric cancer tissues and positively correlated with platelet endothelial cell adhesion molecule-1 (CD31) levels. Moreover, clinical validation, in in vitro and in vivo experiments, confirmed that ESM1 promoted gastric cancer angiogenesis, eventually promoting gastric cancer peritoneal metastasis. Mechanistically, ESM1 promoted tumor angiogenesis by binding to c-Met on the vascular endothelial cell membrane. In addition, our results confirmed that ESM1 upregulated VEGFA, HIF1α, and MMP9 expression and induced angiogenesis by activating the MAPK/ERK pathway. In conclusion, our findings identified the role of ESM1 in gastric cancer angiogenesis and GCPM, thus providing insights into the diagnosis and treatment of advanced gastric cancer.

Development of a prognostic model to predict BLCA based on anoikis-related gene signature: preliminary findings

BACKGROUND

The prevalence of bladder urothelial carcinoma (BLCA) is significant on a global scale. Anoikis is a type of procedural cell death that has an important role in tumor invasion and metastasis. The advent of single-cell RNA sequencing (scRNA-seq) approaches has revolutionized the genomics field by providing unprecedented opportunities for elucidating cellular heterogeneity. Understanding the mechanisms associated with anoikis in BLCA is essential to improve its survival rate.

METHODS

Data on BLCA and clinical information were acquired from the databases of The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). ARGs were obtained from Genecards and Harmonizome databases. According to univariate Cox regression analysis, the least absolute shrinkage and selection operator (LASSO) algorithm was utilized to select the ARGs associated with the overall rate (OS). A multivariate Cox regression analysis was carried out to identify eight prognostic ARGs, leading to the establishment of a risk model. The OS rate of BLCA patients was evaluated using Kaplan-Meier survival analysis. To explore the molecular mechanism in low- and high-risk groups, we employed Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Set Enrichment Analysis (GSVA). Immune infiltration landscape estimation was performed using ESTIMATE, CIBERSOT, and single sample gene set enrichment analysis (ssGSEA) algorithms. Patients were categorized into different subgroups through consensus clustering analysis. We employed biological functional enrichment analysis and conducted immune infiltration analysis to examine the disparities in potential biological functions, infiltration of immune cells, immune activities, and responses to immunotherapy.

RESULTS

We identified 647 ARGs and 37 survival-related genes. We further developed a risk scoring model to quantitatively assess the predictive capacity of ARGs. The high-risk score group exhibited an unfavorable prognosis, whereas the low-risk score group demonstrated a converse effect. We also found that the two groups of patients might respond differently to immune targets and anti-tumor drugs.

CONCLUSION

The nomogram with 8 ARGs may help guide treatment of BLCA. The systematic assessment of risk scores can help to design more individualized and precise treatment strategies for BLCA patients.

Prognostic analyses of genes associated with anoikis in breast cancer

Breast cancer (BRCA) is the most diagnosed cancer worldwide and is responsible for the highest cancer-associated mortality among women. It is evident that anoikis resistance contributes to tumour cell metastasis, and this is the primary cause of treatment failure for BRCA. However, anoikis-related gene (ARG) expression profiles and their prognostic value in BRCA remain unclear. In this study, a prognostic model of ARGs based on The Cancer Genome Atlas (TCGA) database was established using a least absolute shrinkage and selection operator analysis to evaluate the prognostic value of ARGs in BRCA. The risk factor graph demonstrated that the low-risk group had longer survival than the high-risk group, implying that the prognostic model had a good performance. We identified 11 ARGs that exhibited differential expression between the two risk groups in TCGA and Gene Expression Omnibus databases. Through Gene Ontology and Kyoto Encyclopaedia of Genes and Genomes enrichment analyses, we revealed that the screened ARGs were associated with tumour progression and metastasis. In addition, a protein-protein interaction network showed potential interactions among these ARGs. Furthermore, gene set enrichment analysis suggested that the Notch and Wnt signalling pathways were overexpressed in the high-risk group, and gene set variation analysis revealed that 38 hallmark genes differed between the two groups. Moreover, Kaplan-Meier survival curves and receiver operating characteristic curves were used to identify five ARGs (CD24, KRT15, MIA, NDRG1, TP63), and quantitative polymerase chain reaction was employed to assess the differential expression of these ARGs. Univariate and multivariate Cox regression analyses were then performed for the key ARGs, with the best prediction of 3 year survival. In conclusion, ARGs might play a crucial role in tumour progression and serve as indicators of prognosis in BRCA.

Activated platelets facilitate hematogenous metastasis of breast cancer by modulating the PDGFR-β/COX-2 axis

Platelets have been widely recognized as a bona fide mediator of malignant diseases, and they play significant roles in influencing various aspects of tumor progression. Paracrine interactions between platelets and tumor cells have been implicated in promoting the dissemination of malignant cells to distant sites. However, the underlying mechanisms of the platelet-tumor cell interactions for promoting hematogenous metastasis are not yet fully understood. We found that activated platelets with high expression of CD36 were prone to release a plethora of growth factors and cytokines, including high levels of PDGF-B, compared to resting platelets. PDGF-B activated the PDGFR-β/COX-2 signaling cascade, which elevated an array of pro-inflammatory factors levels, thereby aggravating tumor metastasis. The collective administration of CD36 inhibitor and COX-2 inhibitor resolved the interactions between platelets and tumor cells. Collectively, our findings demonstrated that targeting the crosstalk between platelets and tumor cells offers potential therapeutic strategies for inhibiting tumor metastasis.

Compound Kushen Injection inhibits epithelial-mesenchymal transition of gastric carcinoma by regulating VCAM1 induced by the TNF signaling pathway

BACKGROUND

Gastric carcinoma (GC) treatment needs to be developed rapidly. Compound Kushen Injection (CKI), a formula from traditional Chinese medicine, has been used clinically in combination with chemotherapy to treat GC with satisfactory results. However, the molecular mechanism by which CKI acts to cure GC is still unclear.

METHODS

In the present study, in vivo and in vitro experiments were used to assess the efficacy of CKI. Using ceRNA microarray and TMT technologies, the molecular mechanism of CKI was further investigated at the transcriptional and protein levels, and a bioinformatics approach was employed to investigate and functionally validate key CKI targets in GC.

RESULTS

When combined with cisplatin (DDP), CKI significantly increased its efficacy in preventing the proliferation and metastasis of GC cells and malignant-looking tumors in mice. High-throughput sequencing data and bioinformatics analysis showed that CKI regulated the TNF signaling pathway, epithelial-mesenchymal transition (EMT), with VCAM1 as a key target. The transcription factors CEBPB, JUN, RELA, NFKB1, the EMT mesenchymal-like cell markers N-cadherin and vimentin, as well as the expression of VCAM1 and its upstream signaling driver TNF, were all downregulated by CKI. In contrast, the expression of the EMT epithelial-like cell marker E-cadherin was upregulated.

CONCLUSION

CKI can effectively inhibit GC growth and metastasis, improve body's immunity, and protect normal tissues from damage. The molecular mechanism by which CKI inhibits metastasis of GC is by regulating VCAM1 induced by the TNF signaling pathway to inhibit EMT of GC. Our results provide an important clue to clarify precisely the multi-scale molecular mechanism of CKI in the treatment of GC.

Identification of A novel anoikis-related genes-based signature for non-small cell lung cancer

The prognostic value of anoikis in NSCLC and its mechanism in tumorigenesis and progress have not been fully elucidated. This study aimed to reveal the correlation between anoikis-related genes (ARGs) and tumor prognosis, to reveal molecular and immune features, and to evaluate the anticancer drug sensitivity and the efficacy of immunotherapy of NSCLC. ARGs were selected from both the GeneCards and Harmonizome databases and then were intersected with the Cancer Genome Atlas (TCGA) database by differential expression analysis, followed by functional analysis of the target ARGs. An ARGs-based prognostic signature was constructed using LASSO (least absolute shrinkage and selection operator) Cox regression analysis; Kaplan-Meier analysis, univariant and multivariant Cox analysis were used to validate the value of this model in NSCLC prognosis. Differential analyses on molecular and immune landscapes were applied in the model. Anticancer drug sensitivity and efficacy in immune-checkpoint inhibitors (ICI) therapy were analyzed. A total of 509 ARGs and 168 differentially expressed ARGs in NSCLC were generated. Functional analysis revealed enrichment in extracolonic apoptotic signaling pathway, collagen-containing ECM, and integrin binding, and indicated an association with the PI3K-Akt signaling pathway. Subsequently, a 14-genes signature was generated. The high-risk group had a worse prognosis, with higherM0 and M2 macrophage infiltration, and fewer CD8 T-cells and T follicular helper (TFH) cells. The high-risk group had higher expression of immune checkpoint genes, HLA-I genes, and higher TIDE scores than the low-risk group, leading to less benefit of ICI therapy. Additionally, an Immunohistochemical staining comparison revealed that FADD was highly expressed in tumor tissue, compared to normal tissue, consistent with the previous results.

Natural products targeting signaling pathways associated with regulated cell death in gastric cancer: Recent advances and perspectives

Gastric cancer (GC) is one of the most serious gastrointestinal malignancies with high morbidity and mortality. The complexity of GC process lies in the multi-phenotypic linkage regulation, in which regulatory cell death (RCD) is the core link, which largely dominates the fate of GC cells and becomes a key determinant of GC development and prognosis. In recent years, increasing evidence has been reported that natural products can prevent and inhibit the development of GC by regulating RCDs, showing great therapeutic potential. In order to further clarify its key regulatory characteristics, this review focused on specific expressions of RCDs, combined with a variety of signaling pathways and their crosstalk characteristics, sorted out the key targets and action rules of natural products targeting RCD. It is highlighted that a variety of core biological pathways and core targets are involved in the decision of GC cell fate, including the PI3K/Akt signaling pathway, MAPK-related signaling pathways, p53 signaling pathway, ER stress, Caspase-8, gasdermin D (GSDMD), and so on. Moreover, natural products target the crosstalk of different RCDs by modulating above signaling pathways. Taken together, these findings suggest that targeting various RCDs in GC with natural products is a promising strategy, providing a reference for further clarifying the molecular mechanism of natural products treating GC, which warrants further investigations in this area.

Identification of anoikis-related subtypes and development of risk stratification system in skin cutaneous melanoma

Background

Anoikis, a form of apoptosis induced by cell detachment, plays a key role in cancer metastasis. However, the potential roles of anoikis-related genes (ARGs) in assessing the prognosis of skin cutaneous melanoma (SKCM) and the tumor microenvironment (TME) remain unclear.

Methods

The data from TCGA corresponding to transcriptomic expression patterns for patients with SKCM were downloaded and utilized to screen distinct molecular subtypes by a non-negative matrix factorization algorithm. The prognostic signature was constructed by least absolute shrinkage and selection operator (LASSO) Cox regression and was validated in SKCM patients from the GEO cohort. Moreover, the relationship of the ARG_score with prognosis, tumor-infiltrating immune cells, gene mutation, microsatellite instability (MSI), and immunotherapy efficacy.

Results

We screened 100 anoikis-related differentially expressed genes between SKCM tissues and normal skin tissues, which could divide all patients into three different subtypes with significantly distinct prognosis and immune cell infiltration. Then, an anoikis-related signature was developed based on subtype-related DEGs, which could classify all SKCM patients into low and high ARG_score groups with differing overall survival (OS) rates. ARG_score was confirmed to be a strong independent prognostic indicator for SKCM patients. By combining ARG_score with clinicopathological features, a nomogram was constructed, which could accurately predict the individual OS of patients with SKCM. Moreover, low ARG_score patients presented with higher levels of immune cell infiltration, TME score, higher tumor mutation burden, and better immunotherapy responses.

Conclusions

Our comprehensive analysis of ARGs in SKCM provides important insights into the immunological microenvironment within the tumor of SKCM patients and helps to forecast prognosis and the response to immunotherapy in SKCM patients, thereby making it easier to tailor more effective treatment strategies to individual patients.

Extracellular matrix remodeling in tumor progression and immune escape: from mechanisms to treatments

The malignant tumor is a multi-etiological, systemic and complex disease characterized by uncontrolled cell proliferation and distant metastasis. Anticancer treatments including adjuvant therapies and targeted therapies are effective in eliminating cancer cells but in a limited number of patients. Increasing evidence suggests that the extracellular matrix (ECM) plays an important role in tumor development through changes in macromolecule components, degradation enzymes and stiffness. These variations are under the control of cellular components in tumor tissue via the aberrant activation of signaling pathways, the interaction of the ECM components to multiple surface receptors, and mechanical impact. Additionally, the ECM shaped by cancer regulates immune cells which results in an immune suppressive microenvironment and hinders the efficacy of immunotherapies. Thus, the ECM acts as a barrier to protect cancer from treatments and supports tumor progression. Nevertheless, the profound regulatory network of the ECM remodeling hampers the design of individualized antitumor treatment. Here, we elaborate on the composition of the malignant ECM, and discuss the specific mechanisms of the ECM remodeling. Precisely, we highlight the impact of the ECM remodeling on tumor development, including proliferation, anoikis, metastasis, angiogenesis, lymphangiogenesis, and immune escape. Finally, we emphasize ECM "normalization" as a potential strategy for anti-malignant treatment.

Biodegradable nanoplatform upregulates tumor microenvironment acidity for enhanced cancer therapy via synergistic induction of apoptosis, ferroptosis, and anti-angiogenesis

Chemodynamic therapy of cancer is limited by insufficient endogenous H₂O₂ generation and acidity in the tumor microenvironment (TME). Herein, we developed a biodegradable theranostic platform (pLMOFePt-TGO) involving composite of dendritic organosilica and FePt alloy, loaded with tamoxifen (TAM) and glucose oxidase (GOx), and encapsulated by platelet-derived growth factor-B (PDGFB)-labeled liposomes, that effectively uses the synergy among chemotherapy, enhanced chemodynamic therapy (CDT), and anti-angiogenesis. The increased concentration of glutathione (GSH) present in the cancer cells induces the disintegration of pLMOFePt-TGO, releasing FePt, GOx, and TAM. The synergistic action of GOx and TAM significantly enhanced the acidity and H₂O₂ level in the TME by aerobiotic glucose consumption and hypoxic glycolysis pathways, respectively. The combined effect of GSH depletion, acidity enhancement, and H₂O₂ supplementation dramatically promotes the Fenton-catalytic behavior of FePt alloys, which, in combination with tumor starvation caused by GOx and TAM-mediated chemotherapy, significantly increases the anticancer efficacy of this treatment. In addition, T₂-shortening caused by FePt alloys released in TME significantly enhances contrast in the MRI signal of tumor, enabling a more accurate diagnosis. Results of in vitro and in vivo experiments suggest that pLMOFePt-TGO can effectively suppress tumor growth and angiogenesis, thus providing an exciting potential strategy for developing satisfactory tumor theranostics.

Single-cell sequencing of ascites fluid illustrates heterogeneity and therapy-induced evolution during gastric cancer peritoneal metastasis

Peritoneal metastasis is the leading cause of death for gastrointestinal cancers. The native and therapy-induced ascites ecosystems are not fully understood. Here, we characterize single-cell transcriptomes of 191,987 ascites cancer/immune cells from 35 patients with/without gastric cancer peritoneal metastasis (GCPM). During GCPM progression, an increase is seen of monocyte-like dendritic cells (DCs) that are pro-angiogenic with reduced antigen-presenting capacity and correlate with poor gastric cancer (GC) prognosis. We also describe the evolution of monocyte-like DCs and regulatory and proliferative T cells following therapy. Moreover, we track GC evolution, identifying high-plasticity GC clusters that exhibit a propensity to shift to a high-proliferative phenotype. Transitions occur via the recently described, autophagy-dependent plasticity program, paligenosis. Two autophagy-related genes (MARCKS and TXNIP) mark high-plasticity GC with poorer prognosis, and autophagy inhibitors induce apoptosis in patient-derived organoids. Our findings provide insights into the developmental trajectories of cancer/immune cells underlying GCPM progression and therapy resistance.

Targeting Transcription Factors ATF5, CEBPB and CEBPD with Cell-Penetrating Peptides to Treat Brain and Other Cancers

Developing novel therapeutics often follows three steps: target identification, design of strategies to suppress target activity and drug development to implement the strategies. In this review, we recount the evidence identifying the basic leucine zipper transcription factors ATF5, CEBPB, and CEBPD as targets for brain and other malignancies. We describe strategies that exploit the structures of the three factors to create inhibitory dominant-negative (DN) mutant forms that selectively suppress growth and survival of cancer cells. We then discuss and compare four peptides (CP-DN-ATF5, Dpep, Bpep and ST101) in which DN sequences are joined with cell-penetrating domains to create drugs that pass through tissue barriers and into cells. The peptide drugs show both efficacy and safety in suppressing growth and in the survival of brain and other cancers in vivo, and ST101 is currently in clinical trials for solid tumors, including GBM. We further consider known mechanisms by which the peptides act and how these have been exploited in rationally designed combination therapies. We additionally discuss lacunae in our knowledge about the peptides that merit further research. Finally, we suggest both short- and long-term directions for creating new generations of drugs targeting ATF5, CEBPB, CEBPD, and other transcription factors for treating brain and other malignancies.

PDGFB-targeted functional MRI nanoswitch for activatable T1-T2 dual-modal ultra-sensitive diagnosis of cancer

As one of the most significant imaging modalities currently available, magnetic resonance imaging (MRI) has been extensively utilized for clinically accurate cancer diagnosis. However, low signal-to-noise ratio (SNR) and low specificity for tumors continue to pose significant challenges. Inspired by the distance-dependent magnetic resonance tuning (MRET) phenomenon, the tumor microenvironment (TME)-activated off-on T₁-T₂ dual-mode MRI nanoswitch is presented in the current study to realize the sensitive early diagnosis of tumors. The tumor-specific nanoswitch is designed and manufactured on the basis of PDGFB-conjugating ferroferric oxide coated by Mn-doped silica (PDGFB-FMS), which can be degraded under the high-concentration GSH and low pH in TME to activate the T₁-T₂ dual-mode MRI signals. The tumor-specific off-on dual-mode MRI nanoswitch can significantly improve the SNR and is used successfully for the accurate diagnosis of early-stage tumors, particularly for orthotopic prostate cancer. In addition, the systemic delivery of the nanoswitch did not cause blood or tissue damage, and it can be excreted out of the body in a timely manner, demonstrating excellent biosafety. Overall, the strategy is a significant step in the direction of designing off-on dual-mode MRI nanoprobes to improve imaging accuracy, which opens up new avenues for the development of new MRI probes.

An anoikis-based signature for predicting prognosis in hepatocellular carcinoma with machine learning

Background: Hepatocellular carcinoma (HCC) is a common malignancy with high mortality worldwide. Despite advancements in diagnosis and treatment in recent years, there is still an urgent unmet need to explore the underlying mechanisms and novel prognostic markers. Anoikis has received considerable attention because of its involvement in the progression of human malignancies. However, the potential mechanism of anoikis-related genes (ANRGs) involvement in HCC progression remains unclear. Methods: We use comprehensive bioinformatics analyses to determine the expression profile of ANRGs and their prognostic implications in HCC. Next, a risk score model was established by least absolute shrinkage and selection operator (Lasso) Cox regression analysis. Then, the prognostic value of the risk score in HCC and its correlation with clinical characteristics of HCC patients were further explored. Additionally, machine learning was utilized to identify the outstanding ANRGs to the risk score. Finally, the protein expression of DAP3 was examined on a tissue microarray (TMA), and the potential mechanisms of DAP3 in HCC was explored. Results: ANRGs were dysregulated in HCC, with a low frequency of somatic mutations and associated with prognosis of HCC patients. Then, nine ANRGs were selected to construct a risk score signature based on the LASSO model. The signature presented a strong ability of risk stratification and prediction for overall survival in HCC patients.Additionally, high risk scores were closely correlated with unfavorable clinical features such as advanced pathological stage, poor histological differentiation and vascular invasion. Moreover, The XGBoost algorithm verified that DAP3 was an important risk score contributor. Further immunohistochemistry determined the elevated expression of DAP3 in HCC tissues compared with nontumor tissues. Finally, functional analyses showed that DAP3 may promote HCC progression through multiple cancer-related pathways and suppress immune infiltration. Conclusion: In conclusion, the anoikis-based signature can be utilized as a novel prognostic biomarker for HCC, and DAP3 may play an important role in the development and progression of HCC.

Construction of a novel anoikis-related prognostic model and analysis of its correlation with infiltration of immune cells in neuroblastoma

Background

Anoikis resistance (AR) plays an important role in the process of metastasis, which is an important factor affecting the risk stage of neuroblastoma (NB). This study aims to construct an anoikis-related prognostic model and analyze the characteristics of hub genes, important pathways and tumor microenvironment of anoikis-related subtypes of NB, so as to provide help for the clinical diagnosis, treatment and research of NB.

Methods

We combined transcriptome data of GSE49710 and E-MTAB-8248, screened anoikis-related genes (Args) closely related to the prognosis of NB by univariate cox regression analysis, and divided the samples into anoikis-related subtypes by consistent cluster analysis. WGCNA was used to screen hub genes, GSVA and GSEA were used to analyze the differentially enriched pathways between anoikis-related subtypes. We analyzed the infiltration levels of immune cells between different groups by SsGSEA and CIBERSORT. Lasso and multivariate regression analyses were used to construct a prognostic model. Finally, we analyzed drug sensitivity through the GDSC database.

Results

721 cases and 283 Args were included in this study. All samples were grouped into two subtypes with different prognoses. The analyses of WGCNA, GSVA and GSEA suggested the existence of differentially expressed hub genes and important pathways in the two subtypes. We further constructed an anoikis-related prognostic model, in which 15 Args participated. This model had more advantages in evaluating the prognoses of NB than other commonly used clinical indicators. The infiltration levels of 9 immune cells were significantly different between different risk groups, and 13 Args involved in the model construction were correlated with the infiltration levels of immune cells. There was a relationship between the infiltration levels of 6 immune cells and riskscores. Finally, we screened 15 drugs with more obvious effects on NB in high-risk group.

Conclusion

There are two anoikis-related subtypes with different prognoses in the population of NB. The anoikis-related prognostic model constructed in this study can accurately predict the prognoses of children with NB, and has a good guiding significance for clinical diagnosis, treatment and research of NB.

Review on Metal-Based Theranostic Nanoparticles for Cancer Therapy and Imaging

Theranostic agents are promising due to their ability to diagnose, treat and monitor different types of cancer using a variety of imaging modalities. The advantage specifically of nanoparticles is that they can accumulate easily at the tumor site due to the large gaps in blood vessels near tumors. Such high concentration of theranostic agents at the target site can lead to enhancement in both imaging and therapy. This article provides an overview of nanoparticles that have been used for cancer theranostics, and the different imaging, treatment options and signaling pathways that are important when using nanoparticles for cancer theranostics. In particular, nanoparticles made of metal elements are emphasized due to their wide applications in cancer theranostics. One important aspect discussed is the ability to combine different types of metals in one nanoplatform for use as multimodal imaging and therapeutic agents for cancer.

Construction of anoikis-related lncRNAs risk model: Predicts prognosis and immunotherapy response for gastric adenocarcinoma patients

Background: Anoikis acts as a programmed cell death that is activated during carcinogenesis to remove undetected cells isolated from ECM. Further anoikis based risk stratification is expected to provide a deeper understanding of stomach adenocarcinoma (STAD) carcinogenesis. Methods: The information of STAD patients were acquired from TCGA dataset. Anoikis-related genes were obtained from the Molecular Signatures Database and Pearson correlation analysis was performed to identify the anoikis-related lncRNAs (ARLs). We performed machine learning algorithms, including Univariate Cox regression and Least Absolute Shrinkage and Selection Operator (Lasso) analyses on the ARLs to build the OS-score and OS-signature. Clinical subgroup analysis, tumor mutation burden (TMB) detection, drug susceptibility analysis, immune infiltration and pathway enrichment analysis were further performed to comprehensive explore the clinical significance. Results: We established a STAD prognostic model based on five ARLs and its prognostic value was verified. Survival analysis showed that the overall survival of high-risk score patients was significantly shorter than that of low-risk score patients. The column diagrams show satisfactory discrimination and calibration. The calibration curve verifies the good agreement between the prediction of the line graph and the actual observation. TIDE analysis and drug sensitivity analysis showed significant differences between different risk groups. Conclusion: The novel prognostic model based on anoikis-related lncRNAs we identified could be used for prognosis prediction and precise therapy in gastric adenocarcinoma.

Multi-Transcriptomic Analysis Reveals the Heterogeneity and Tumor-Promoting Role of SPP1/CD44-Mediated Intratumoral Crosstalk in Gastric Cancer

GC is a fatal disease with high heterogeneity and invasiveness. Recently, SPP1 has been reported to be involved in the tumor progression of multiple human cancers; however, the role of SPP1 in GC heterogeneity and whether it is associated with the invasiveness and mortality of GC remain unclear. Here, we combined multiple RNA sequencing approaches to evaluate the impact of SPP1 on GC. Through bulk RNA sequencing (bulk RNA-seq) and immunohistochemistry (IHC), we found that SPP1 was highly expressed in GC, and high levels of SPP1 were associated with macrophage infiltration, an advanced tumor stage, and higher mortality for advanced GC patients. Furthermore, through simultaneous single-cell and spatial analysis, we demonstrated that SPP1⁺ macrophages are tumor-specific macrophages unique to cancer and enriched in the deep layer of GC tissue. Cell-cell communication analysis revealed that SPP1/CD44 interactions between SPP1⁺ macrophages and their localized tumor epithelial cells could activate downstream target genes in epithelial cells to promote dynamic changes in intratumor heterogeneity. Moreover, these activated genes were found to be closely associated with poor clinical GC outcomes and with cancer-related pathways that promote GC progression, as shown by survival analysis and enrichment analysis, respectively. Collectively, our study reveals that tumor-specific SPP1⁺ macrophages drive the architecture of intratumor heterogeneity to evolve with tumor progression and that SPP1 may serve as a prognostic marker for advanced GC patients, as well as a potential therapeutic target for GC.

Molecular biology of pancreatic neuroendocrine tumors: From mechanism to translation

Pancreatic neuroendocrine tumors (pNETs) are a group of heterogeneous tumors originated from progenitor cells. As these tumors are predominantly non-functional, most of them display asymptomatic characteristics, making it difficult to be realized from early onset. Therefore, patients with pNETs are usually diagnosed with metastatic disease or at a late disease stage. The relatively low incidence also limits our understanding of the biological background of pNETs, which largely impair the development of new effective drugs. The fact that up to 10% of pNETs develop in patients with genetic syndromes have promoted researchers to focus on the gene mutations and driver mutations in MEN1, DAXX/ATRX and mTOR signaling pathway genes have been implicated in disease development and progression. Recent advances in sequencing technologies have further enriched our knowledge of the complex molecular landscape of pNETs, pointing out crucial roles of genes in DNA damage pathways, chromosomal and telomere alterations and epigenetic dysregulation. These novel findings may not only benefit early diagnosis of pNETs, but also help to uncover tumor heterogeneity and shape the future of translational medical treatment. In this review, we focus on the current molecular biology of pNETs and decipher how these findings may translate into future development of targeted therapy.

Hypoxia-Induced CD36 Expression in Gastric Cancer Cells Promotes Peritoneal Metastasis via Fatty Acid Uptake

Background

The lipid scavenger receptor cluster of differentiation 36 (CD36) has been shown to have a pro-metastatic function in several cancers. Adipose tissue, a favorable site for peritoneal metastasis (PM) from gastric cancer (GC), promotes this process by providing free fatty acids (FFAs); however, the role of CD36 in PM progression from GC remains to be elucidated.

Materials and Methods

We evaluated CD36 expression in the GC cells under various conditions. CD36 overexpressing (CD36OE) MKN45 cells were prepared and their migration and invasive properties were assessed. A PM mouse model was used to investigate the biological effects of palmitic acid (PA) and CD36. Furthermore, we examined the clinical role of CD36 expression in 82 human PM samples by immunohistochemical staining.

Results

Hypoxia markedly increased CD36 expression in GC cells. In normoxia, only CD36OE MKN45 cells treated with PA showed an increase in migration and invasion abilities. An increased expression of active Rac1 and Cdc42 was observed, which decreased following etomoxir treatment. Conversely, hypoxia increased those capacities of both vector and CD36OE MKN45 cells. In a mouse model transplanted with CD36OE MKN45 cells, more peritoneal tumors were observed in the high-fat diet group than those in the normal diet group. In clinical samples, 80% of PM lesions expressed CD36, consistent with hypoxic regions, indicating a significant association with prognosis.

Conclusion

Our findings indicate that a hypoxia in the peritoneal cavity induces CD36 expression in GC cells, which contributes to PM through the uptake of FFAs.

Arginine methylation of MTHFD1 by PRMT5 enhances anoikis resistance and cancer metastasis

Metastasis accounts for the major cause of cancer-related mortality. How disseminated tumor cells survive under suspension conditions and avoid anoikis is largely unknown. Here, using a metabolic enzyme-centered CRISPR-Cas9 genetic screen, we identified methylenetetrahydrofolate dehydrogenase, cyclohydrolase and formyltetrahydrofolate synthetase 1 (MTHFD1) as a novel suppressor of anoikis. MTHFD1 depletion obviously restrained the capacity of cellular antioxidant defense and inhibited tumor distant metastasis. Mechanistically, MTHFD1 was found to bind the protein arginine methyltransferase 5 (PRMT5) and then undergo symmetric dimethylation on R173 by PRMT5. Under suspension conditions, the interaction between MTHFD1 and PRMT5 was strengthened, which increased the symmetric dimethylation of MTHFD1. The elevated methylation of MTHFD1 largely augmented its metabolic activity to generate NADPH, therefore leading to anoikis resistance and distant organ metastasis. Therapeutically, genetic depletion or pharmacological inhibition of PRMT5 declined tumor distant metastasis. And R173 symmetric dimethylation status was associated with metastasis and prognosis of ESCC patients. In conclusion, our study uncovered a novel regulatory role and therapeutic implications of PRMT5/MTHFD1 axis in facilitating anoikis resistance and cancer metastasis.

Molecular Mechanisms and Potential Rationale of Immunotherapy in Peritoneal Metastasis of Advanced Gastric Cancer

Peritoneal metastasis (PM) is one of the most frequent metastasis patterns of gastric cancer (GC), and the prognosis of patients with PM is very dismal. According to Paget’s theory, disseminated free cancer cells are seeded and survive in the abdominal cavity, adhere to the peritoneum, invade the subperitoneal tissue, and proliferate through angiogenesis. In these sequential processes, several key molecules are involved. From a therapeutic point of view, immunotherapy with chemotherapy combination has become the standard of care for advanced GC. Several clinical trials of newer immunotherapy agents are ongoing. Understanding of the molecular process of PM and the potential rationale of immunotherapy for PM treatment is necessary. Beyond understanding of the molecular aspect of PM, many studies have been conducted on the modality of treatment of PM. Notably, intraperitoneal approaches, including chemotherapy or immunotherapy, have been conducted, because systemic treatment of PM has limitations. In this study, we reviewed the molecular mechanisms and immunologic aspects of PM, and intraperitoneal approaches under investigation for treating PM.

PDGFB targeting biodegradable FePt alloy assembly for MRI guided starvation-enhancing chemodynamic therapy of cancer

The application of chemodynamic therapy (CDT) for cancer is a serious challenge owing to the low efficiency of the Fenton catalyst and insufficient H₂O₂ expression in cells. Herein, we fabricated a PDGFB targeting, biodegradable FePt alloy assembly for magnetic resonance imaging (MRI)-guided chemotherapy and starving-enhanced chemodynamic therapy for cancer using PDGFB targeting, pH-sensitive liposome-coated FePt alloys, and GOx (pLFePt-GOx). We found that the Fenton-catalytic activity of FePt alloys was far stronger than that of traditional ultrasmall iron oxide nanoparticle (UION). Upon entry into cancer cells, pLFePt-GOx nanoliposomes degraded into many tiny FePt alloys and released GOx owing to the weakly acidic nature of the tumor microenvironment (TME). The released GOx-mediated glucose consumption not only caused a starvation status but also increased the level of cellular H₂O₂ and acidity, promoting Fenton reaction by FePt alloys and resulting in an increase in reactive oxygen species (ROS) accumulation in cells, which ultimately realized starving-enhanced chemodynamic process for killing tumor cells. The anticancer mechanism of pLFePt-GOx involved ROS-mediated apoptosis and ferroptosis, and glucose depletion-mediated starvation death. In the in vivo assay, the systemic delivery of pLFePt-GOx showed excellent antitumor activity with low biological toxicity and significantly enhanced T₂-weighted magnetic resonance imaging (MRI) signal of the tumor, indicating that pLFePt-GOx can serve as a highly efficient theranostic tool for cancer. This work thus describes an effective, novel multi-modal cancer theranostic system.

CircCEMIP promotes anoikis-resistance by enhancing protective autophagy in prostate cancer cells

Background

Circular RNAs (circRNAs) are essential participants in the development and progression of various malignant tumors. Previous studies have shown that cell migration-inducing protein (CEMIP) accelerates prostate cancer (PCa) anoikis resistance (AR) by activating autophagy. This study focused on the effect of circCEMIP on PCa metastasis.

Methods

This study gradually revealed the role of circ_0004585 in PCa anoikis resistance via quantitative real-time PCR (qRT-PCR) analysis, western blotting, pull-down assays, and dual fluorescence reporter assays.

Results

Functionally, circ_0004585 promoted PCa cells invasion and metastasis both in vitro and in vivo. Mechanistically, circ_0004585 directly interacted with miR-1248 to upregulate target gene expression. Furthermore, target prediction and dual-luciferase reporter assays identified transmembrane 9 superfamily member 4 (TM9SF4) as a potential miR-1248 target. Pathway analysis revealed that TM9SF4 activated autophagy to promote PCa cells anoikis resistance via mTOR phosphorylation.

Conclusions

These results demonstrated that circ_0004585 played an oncogenic role during PCa invasion and metastasis by targeting the miR-1248/TM9SF4 axis while providing new insight into therapeutic strategy development for metastatic PCa.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-022-02381-7.

LncRNA MNX1-AS1: A novel oncogenic propellant in cancers

To date, recent studies have shown that long non-coding RNAs (lncRNAs) are key players in gene regulation processes involved in cancer pathogenesis. In general, Motor neuron and pancreas homeobox 1-antisense RNA1 (MNX1-AS1) is highly expressed in all cancers as reported so far and exerts oncogenic effects through different mechanisms. In this review, we comprehensively summarize the detailed mechanisms of potential functions of MNX1-AS1 in different cancer types as well as the latest knowledge highlighting the potential of MNX1-AS1 as a therapeutic target for cancer. Aberrant expression of MNX1-AS1 closely correlates with clinicopathological parameters. such as lymphatic metastasis, tumor size, tumor stage, OS and DFS. Thus, MNX1-AS1 can be used as a diagnostic and prognostic biomarker or even a therapeutic prognostic target. This article reviews its function, molecular mechanism and clinical prognosis in various malignancies.

MicroRNA-31: a pivotal oncogenic factor in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) continuously constitutes a major challenge for treatment and prognosis due to approximately half of treated OSCC patients dying from locoregional recurrences and distant metastases. MicroRNA-31 (miR-31), an early mammalian miRNA identified, has been gaining importance in the field of OSCC research in recent years. This comprehensive review was conducted for the first time to summarize the current evidence on the association between miR-31 and OSCC. The vast majority of relevant studies (20/21, 95%) demonstrated that miR-31 was an oncogenic factor in the tumorigenesis and progression of OSCC. miR-31 expression is significantly upregulated in plasma, saliva, and tumor tissue of OSCC. miR-31 played an essential role in OSCC development by constituting a complex network with its targeted genes (e.g. RhoA, FIH, ACOX1, VEGF, SIRT3, LATS2, KANK1, and NUMB) and the signaling cascades (e.g. EGF-AKT signaling axis, ERK-MMP9 cascade, Hippo pathway, Wnt signaling, and MCT1/MCT4 regulatory cascade). This review highlights that miR-31 might function as a potential diagnostic, prognostic, and predictive biomarker for OSCC. Further studies are still warranted to better illuminate the clinicopathological features and the molecular mechanisms of miR-31-mediated OSCC development.

The Development of Peritoneal Metastasis from Gastric Cancer and Rationale of Treatment According to the Mechanism

In the present article, we describe the normal structure of the peritoneum and review the mechanisms of peritoneal metastasis (PM) from gastric cancer (GC). The structure of the peritoneum was studied by a double-enzyme staining method using alkaline-phosphatase and 5′-nucreotidase, scanning electron microscopy, and immunohistological methods. The fundamental structure consists of three layers, mesothelial cells and a basement membrane (layer 1), macula cribriformis (MC) (layer 2), and submesothelial connective tissue containing blood vessels and initial lymphatic vessels, attached to holes in the MC (layer 3). Macro molecules and macrophages migrate from mesothelial stomata to the initial lymphatic vessels through holes in the MC. These structures are characteristically found in the diaphragm, omentum, paracolic gutter, pelvic peritoneum, and falciform ligament. The first step of PM is spillage of cancer cells (peritoneal free cancer cells; PFCCs) into the peritoneal cavity from the serosal surface of the primary tumor or cancer cell contamination from lymphatic and blood vessels torn during surgical procedures. After PFCCs adhere to the peritoneal surface, PMs form by three processes, i.e., (1) trans-mesothelial metastasis, (2) trans-lymphatic metastasis, and (3) superficial growing metastasis. Because the intraperitoneal (IP) dose intensity is significantly higher when generated by IP chemotherapy than by systemic chemotherapy, IP chemotherapy has a great role in the treatment of PFCCs, superficial growing metastasis, trans-lymphatic metastasis and in the early stages of trans-mesothelial metastasis. However, an established trans-mesothelial metastasis has its own interstitial tissue and vasculature which generate high interstitial pressure. Accordingly, it is reasonable to treat established trans-mesothelial metastasis by bidirectional chemotherapy from both IP and systemic chemotherapy.