Integrin Subunit beta 8 (ITGB8) Upregulation Is an Independent Predictor of Unfavorable Survival of High-Grade Serous Ovarian Carcinoma Patients

A novel ITGB8 transcript variant sustains ovarian cancer cell survival through genomic instability and altered ploidy on a mutant p53 background

BACKGROUND

Transcript variants and protein isoforms are central to unique tissue functions and maintenance of homeostasis, in addition to being associated with aberrant states such as cancer, where their crosstalk with the mutated tumor suppressor p53 may contribute to genomic instability and chromosomal rearrangements. We previously identified several novel splice variants in ovarian cancer RNA-sequencing datasets; herein, we aimed to elucidate the biological effects of the Integrin Subunit Beta 8 variant (termed pITGB8-205).

METHODS

Resolution of the full-length sequence of pITGB8-205 through rapid amplification of cDNA ends (RACE-PCR). Cell cycle analysis and karyotype studies were performed to further explore genomic instability. RNA-seq and proteomics analyses were used to identify the differential expression of the genes.

RESULTS

This full-length study revealed a unique 5' sequence in pITGB8-205 that differed from the reported ITGB8-205 sequence, suggesting differential regulation of this novel transcript. Under a p53 mutant background, overexpression of pITGB8-205 triggered genetic instability reminiscent of oncogene-induced replicative stress with extensive abnormal mitoses and chromosomal and nuclear aberrations indicative of chromosomal instability, leading to near whole-genome duplication that imposes energy stress on cellular resources. Micronuclei and aneuploidy are striking features of pITGB8-205-overexpressing p53-mutant cells but are not enhanced in p53 wild-type (WT) cells. RNA-seq and proteomics analyses further suggested that p53 inactivation in ovarian cancer provides a permissive intracellular molecular niche for pITGB8-205 to mediate its effects on genomic instability. This observation is pivotal considering that most high-grade serous ovarian carcinoma (HGSC) tumors express mutant p53. The resulting aneuploid clones with enhanced self-renewal and survival capabilities disrupt clonal dominance under stress yet maintain a balance between replicative stress and prosurvival advantages.

CONCLUSION

pITGB8-205-overexpressing clones sustain ovarian tumor cell survival, achieve homeostasis and are formidable opponents of therapy.

Spatial Heterogeneity of Immune Regulators Drives Dynamic Changes in Local Immune Responses, Affecting Disease Outcomes in Pancreatic Cancer

PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) is considered a low-immunogenic (LI) tumor with a "cold" tumor microenvironment and is mostly unresponsive to immune checkpoint blockade therapies. In this study, we decipher the impact of intratumoral heterogeneity of immune determinants on antitumor responses.

EXPERIMENTAL DESIGN

We performed spatial proteomic and transcriptomic analyses and multiplex immunofluorescence on multiple tumor regions, including tumor center (TC) and invasive front (IF), from 220 patients with PDAC, classified according to their transcriptomic immune signaling into high-immunogenic PDAC (HI-PDAC, n = 54) and LI PDAC (LI-PDAC, n = 166). Spatial compartments (tumor: pancytokeratin+/CD45- and leukocytes: pancytokeratin-/CD45+) were defined by fluorescence imaging.

RESULTS

HI-PDAC exhibited higher densities of cytotoxic T lymphocytes with upregulation of T-cell priming-associated immune determinants, including CD40, ITGAM, glucocorticoid-induced TNF-related receptor, CXCL10, granzyme B, IFNG, and HLA-DR, which were significantly more prominent at the IF than at the TC. In contrast, LI-PDAC exhibited immune-evasive tumor microenvironments with downregulation of immune determinants and a negative gradient from TC to IF. Patients with HI-PDAC had significantly better outcomes but showed more frequently exhausted immune phenotypes.

CONCLUSIONS

Our results indicate strategic differences in the regulation of immune determinants, leading to different levels of effectiveness of antitumor responses between HI and LI tumors and dynamic spatial changes, which affect the evolution of immune evasion and patient outcomes. This finding supports the coevolution of tumor and immune cells and may help define therapeutic vulnerabilities to improve antitumor immunity and harness the responsiveness to immune checkpoint inhibitors in patients with PDAC.

B4GALT5 a sialylation-related genes associated with patient prognosis and immune microenvironment in ovarian cancer and pan-cancer

BACKGROUND

Ovarian cancer (OC) is the predominant primary tumor in the human reproductive system. Abnormal sialylation has a significant impact on tumor development, metastasis, immune evasion, angiogenesis, and treatment resistance. B4GALT5, a gene associated with sialylation, plays a crucial role in ovarian cancer, and may potentially affect clinicopathological characteristics and prognosis.

METHODS

We conducted a comprehensive search across TIMER, GEPIA2, GeneMANIA, and Metascape to obtain transcription profiling data of ovarian cancer from The Cancer Genome Atlas (TCGA). The expression of B4GALT5 was test by immunohistochemistry. To investigate the impact of B4GALT5 on growth and programmed cell death in OC cells, we performed transwell assays and western blots.

RESULTS

The presence of B4GALT5 was strongly associated with an unfavorable outcome in OC. B4GALT5 significantly promoted the proliferation of OC cells. Upon analyzing gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG), it was discovered that B4GALT5 played a crucial role in the extracellular matrix, particularly in collagen-containing structures, and exhibited correlations with ECM-receptor interactions, transcriptional dysregulation in cancer, as well as the interleukin-1 receptor signaling pathway. Furthermore, there is a clear link between B4GALT5 and the tumor immune microenvironment in OC. Moreover, B4GALT5 exhibits favorable expression levels across various types of cancers, including CHOL, KIRC, STAD and UCES.

CONCLUSION

In conclusion, it is widely believed that B4GALT5 plays a pivotal role in the growth and progression of OC, with its heightened expression serving as an indicator of unfavorable outcomes. Moreover, B4GALT5 actively participates in shaping the cancer immune microenvironment within OC. This investigation has the potential to contribute significantly to a deeper understanding of the substantial involvement of B4GALT5 in human malignancies, particularly OCs.

Proteomic analysis of ascitic extracellular vesicles describes tumour microenvironment and predicts patient survival in ovarian cancer

High-grade serous carcinoma of the ovary, fallopian tube and peritoneum (HGSC), the most common type of ovarian cancer, ranks among the deadliest malignancies. Many HGSC patients have excess fluid in the peritoneum called ascites. Ascites is a tumour microenvironment (TME) containing various cells, proteins and extracellular vesicles (EVs). We isolated EVs from patients' ascites by orthogonal methods and analyzed them by mass spectrometry. We identified not only a set of 'core ascitic EV-associated proteins' but also defined their subset unique to HGSC ascites. Using single-cell RNA sequencing data, we mapped the origin of HGSC-specific EVs to different types of cells present in ascites. Surprisingly, EVs did not come predominantly from tumour cells but from non-malignant cell types such as macrophages and fibroblasts. Flow cytometry of ascitic cells in combination with analysis of EV protein composition in matched samples showed that analysis of cell type-specific EV markers in HGSC has more substantial prognostic potential than analysis of ascitic cells. To conclude, we provide evidence that proteomic analysis of EVs can define the cellular composition of HGSC TME. This finding opens numerous avenues both for a better understanding of EV's role in tumour promotion/prevention and for improved HGSC diagnostics.

PVT1 lncRNA in lung cancer: A key player in tumorigenesis and therapeutic opportunities

The lncRNA PVT1 has emerged as a pivotal component in the intricate landscape of cancer pathogenesis, particularly in lung cancer. PVT1, situated in the 8q24 chromosomal region, has garnered attention for its aberrant expression patterns in lung cancer, correlating with tumor progression, metastasis, and poor prognosis. Numerous studies have unveiled the diverse mechanisms PVT1 contributes to lung cancer pathogenesis. It modulates critical pathways, such as cell proliferation, apoptosis evasion, angiogenesis, and epithelial-mesenchymal transition. PVT1's interactions with other molecules, including microRNAs and proteins, amplify its oncogenic influence. Recent advancements in genomic and epigenetic analyses have also illuminated the intricate regulatory networks that govern PVT1 expression. Understanding PVT1's complex involvement in lung cancer holds substantial clinical implications. Targeting PVT1 presents a promising avenue for developing novel diagnostic biomarkers and therapeutic interventions. This abstract encapsulates the expanding knowledge regarding the oncogenic role of PVT1 in lung cancer, underscoring the significance of further research to unravel its complete mechanistic landscape and exploit its potential for improved patient outcomes.

The action and resistance mechanisms of Lenvatinib in liver cancer

Lenvatinib is a tyrosine kinase inhibitor that prevents the formation of new blood vessels namely by inhibiting tyrosine kinase enzymes as the name suggests. Specifically, Lenvatinib acts on vascular endothelial growth factor receptors 1-3 (VEGFR1-3), fibroblast growth factor receptors 1-4 (FGFR1-4), platelet-derived growth factor receptor-alpha (PDGFRα), tyrosine-kinase receptor (KIT), and rearranged during transfection receptor (RET). Inhibition of these receptors works to inhibit tumor proliferation. It is through these inhibition mechanisms that Lenvatinib was tested to be noninferior to Sorafenib. However, resistance to Lenvatinib is common, making the positive effects of Lenvatinib on a patient's survival null after resistance is acquired. Therefore, it is crucial to understand mechanisms related to Lenvatinib resistance. This review aims to piece together various mechanisms involved in Lenvatinib resistance and summarizes the research done so far investigating it.

Prognostic value and potential molecular mechanism of ITGB superfamily members in hepatocellular carcinoma

We analyzed the prognostic value and potential molecular mechanisms of the members of integrin β (ITGB)superfamily in hepatocellular carcinoma (HCC) using data from The Cancer Genome Atlas (TCGA), cBioPortal, Gene Expression Profiling Interactive Analysis (GEPIA), Human Protein Atlas (HPA) HPA, Search Tool for the Retrieval of Interacting Genes/Proteins, GeneMANIA, Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), TIMER and Gene set enrichment analysis (GSEA) databases. ITGB4/5 mRNA was upregulated in HCC tissues in contrast to the normal liver tissues, whereas ITGB2/3/8 levels were lower in the former. ITGB4 was the most frequently mutated ITGB gene in HCC. Receiver operating characteristic curve (ROC) analysis showed that the expression levels of ITGB2/3/4/5/7/8 had significant diagnostic value in distinguishing HCC tissues from healthy liver tissues, ITGB8 had the highest diagnostic efficacy. The ITGB1/3/6/8 were also upregulated in the HCC tissues in contrast to healthy liver tissues. The expression of ITGB8 was verified by immunohistochemistry (IHC). Furthermore, ITGB6 and ITGB7 expression levels were strongly associated with the overall survival (OS) of HCC patients. The ITGB superfamily members exhibited homology and interactions in protein structure. In addition, ITGB6 together with ITGB7 were negatively related to the infiltration of multiple immune cell populations. GSEA results showed that ITGB6 was enriched in HCC migration and recurrence, whereas ITGB7 was significantly enriched in HIPPO, TOLL and JAK-STAT signaling pathways. In conclusion, ITGB6 and ITGB7 genes are possible to be prognostic biomarkers for HCC.

Circular RNAs in ferroptosis: regulation mechanism and potential clinical application in disease

Ferroptosis, an iron-dependent non-apoptotic form of cell death, is reportedly involved in the pathogenesis of various diseases, particularly tumors, organ injury, and degenerative pathologies. Several signaling molecules and pathways have been found to be involved in the regulation of ferroptosis, including polyunsaturated fatty acid peroxidation, glutathione/glutathione peroxidase 4, the cysteine/glutamate antiporter system Xc-, ferroptosis suppressor protein 1/ubiquinone, and iron metabolism. An increasing amount of evidence suggests that circular RNAs (circRNAs), which have a stable circular structure, play important regulatory roles in the ferroptosis pathways that contribute to disease progression. Hence, ferroptosis-inhibiting and ferroptosis-stimulating circRNAs have potential as novel diagnostic markers or therapeutic targets for cancers, infarctions, organ injuries, and diabetes complications linked to ferroptosis. In this review, we summarize the roles that circRNAs play in the molecular mechanisms and regulatory networks of ferroptosis and their potential clinical applications in ferroptosis-related diseases. This review furthers our understanding of the roles of ferroptosis-related circRNAs and provides new perspectives on ferroptosis regulation and new directions for the diagnosis, treatment, and prognosis of ferroptosis-related diseases.

Aberrant glycosylation of α3 integrins as diagnostic markers in epithelial ovarian cancer

BACKGROUND

Glycans are strongly involved in stability and function of integrins (ITG) and tetraspanin protein CD63 and their respective interaction partners as they are dysregulated in the tumorigenic processes. Glycosylation changes is a universal phenomenon of cancer cells. In this study, glycosylation changes in epithelial ovarian cancer (EOC) are explored using tetraspanin and integrin molecules.

METHODS

ITG and CD63 were immobilized from 10 EOC and 5 benign ovarian cyst fluid on microtiter wells and traced with 3 glycan binding proteins (STn, WGA, UEA) conjugated on europium nanoparticles. Total protein measurements (ITG & CD63 immunoassays) were also performed. The most promising glycovariant candidates identified were then clinically evaluated on the whole cohort of 77 ovarian cyst fluids. Additional testing was performed in ascites fluid samples of liver cirrhosis (n=2) and EOC (n=4).

RESULTS

Sialylated Tn antibody based glycovariants of ITGα3 (ITGα3^STn) and CD63 (CD63^STn) performed better than corresponding protein epitope-based immunoassays, ITGα3^IA and CD63^IA respectively. Combined ITGα3 based assays (ITGα3^IA + ITGα3^STn) detected 49 out of 55 malignant & borderline cases without detecting any of the 22 benign and healthy cysts.

CONCLUSION

Our findings indicate the potential diagnostic application of ITGα3^STn along with total ITGα3^IA, which could help reduce the unnecessary surgeries. The results encourage studying further the potential use of these novel assays to detect EOC at earlier clinical stages.

Long Noncoding RNA CTD-2589M5.4 Inhibits Ovarian Cancer Cell Proliferation, Migration, and Invasion Via Downregulation of the Extracellular Matrix-Receptor Interaction Pathway

Background: The authors' previous study showed that the long noncoding RNA CTD-2589M5.4 was significantly upregulated in multidrug-resistant ovarian cancer cells. However, the role of CTD-2589M5.4 in the progression of ovarian cancer remains unclear. The purpose of this current study was to illuminate the biological function and possible mechanism of CTD-2589M5.4 in ovarian cancer development. Materials and Methods: The expression of CTD-2589M5.4 was examined via real-time quantitative PCR in primary ovarian cancer tissues (POCTs) and ovarian cancer cell lines. The biological function of CTD-2589M5.4 was analyzed via CCK-8 proliferation, wound healing, transwell, and flow cytometry assays in CTD-2589M5.4-overexpressed/silenced and control ovarian cancer cells. The mechanism of CTD-2589M5.4 function in ovarian cancer progression was analyzed utilizing high-throughput RNA-sequencing, Kyoto Encyclopedia of Genes and Genomes analysis, qRT-PCR, Western blot, and rescue experiments. Results: CTD-2589M5.4 expression was decreased in the POCTs and ovarian cancer cells compared with the normal ovarian tissues (p < 0.05) and normal ovarian epithelial cells (p < 0.05). Overexpression of CTD-2589M5.4 inhibited the proliferation, invasion, and migration of ovarian cancer cells, while knockdown of CTD-2589M5.4 had the opposite effect. Furthermore, a total of 750 and 233 genes were notably upregulated and downregulated, respectively, in the CTD-2589M5.4-overexpressed A2780 cells, while the extracellular matrix (ECM)-receptor interaction pathway was significantly downregulated. In addition, overexpression of fibronectin 1 significantly abrogated the tumor suppressive function of CTD-2589M5.4. Conclusions: This study demonstrated that CTD-2589M5.4 could inhibit ovarian cancer cell proliferation, invasion, and migration, at least partially by way of downregulating the ECM-receptor interaction pathway, therefore providing a potential therapeutic target for the prevention and/or treatment of ovarian cancer.

Prediction of risk-associated genes and high-risk liver cancer patients from their mutation profile: Benchmarking of mutation calling techniques

Identification of somatic mutations with high precision is one of the major challenges in the prediction of high-risk liver-cancer patients. In the past, number of mutations calling techniques have been developed that include MuTect2, MuSE, Varscan2, and SomaticSniper. In this study, an attempt has been made to benchmark the potential of these techniques in predicting the prognostic biomarkers for liver cancer. Initially, we extracted somatic mutations in liver cancer patients using Variant Call Format (VCF) and Mutation Annotation Format (MAF) files from the cancer genome atlas. In terms of size, the MAF files are 42 times smaller than VCF files and containing only high-quality somatic mutations. Further, machine learning based models have been developed for predicting high-risk cancer patients using mutations obtained from different techniques. The performance of different techniques and data files have been compared based on their potential to discriminate high and low-risk liver-cancer patients. Based on correlation analysis, we selected 80 genes having significant negative-correlation with the overall survival of liver cancer patients. The univariate survival analysis revealed the prognostic role of highly mutated genes. Single-gene based analysis showed that MuTect2 technique based MAF file has achieved maximum hazard ratio (HRLAMC3) of 9.25 with p-value 1.78E-06. Further, we developed various prediction models using risk-associated top-10 genes for each technique. Our results indicate that MuTect2 technique based VCF files outperform all other methods with maximum Area Under the Receiver-Operating Characteristic (AUROC) curve of 0.765 and HR 4.50 (p-value 3.83E-15). Eventually, VCF file generated using MuTect2 technique performs better among other mutation calling techniques for the prediction of high-risk liver cancer patients. We hope that our findings will provide a useful and comprehensive comparison of various mutation calling techniques for the prognostic analysis of cancer patients. In order to serve the scientific community, we have provided a Python-based pipeline to develop the prediction models using mutation profiles (VCF/MAF) of cancer patients. It is available on GitHub at https://github.com/raghavagps/mutation_bench.

Molecular and cellular mechanisms controlling integrin-mediated cell adhesion and tumor progression in ovarian cancer metastasis: a review

Epithelial ovarian cancer (EOC) is the most lethal gynecological malignancy in the developed world. EOC metastasis is unique since malignant cells detach directly from the primary tumor site into the abdominal fluid and form multicellular aggregates, called spheroids, that possess enhanced survival mechanisms while in suspension. As such, altered cell adhesion properties are paramount to EOC metastasis with cell detachment from the primary tumor, dissemination as spheroids, and reattachment to peritoneal surfaces for secondary tumor formation. The ability for EOC cells to establish and maintain cell–cell contacts in spheroids is critical for cell survival in suspension. Integrins are a family of cell adhesion receptors that play a crucial role in cell–cell and cell-extracellular matrix interactions. These glycoprotein receptors regulate diverse functions in tumor cells and are implicated in multiple steps of cancer progression. Altered integrin expression is detected in numerous carcinomas, where they play a role in cell migration, invasion, and anchorage-independent survival. Like that observed for other carcinomas, epithelial-mesenchymal transition (EMT) occurs during metastasis and integrins can function in this process as well. Herein, we provide a review of the evidence for integrin-mediated cell adhesion mechanisms impacting steps of EOC metastasis. Taken together, targeting integrin function may represent a potential therapeutic strategy to inhibit progression of advanced EOC.

Integrative RNA-Seq and H3 Trimethylation ChIP-Seq Analysis of Human Lung Cancer Cells Isolated by Laser-Microdissection

Simple Summary

Tissue heterogeneity is one of the major problems in cancer genomics. Thus, we developed and conducted an RNA-Seq and ChIP-Seq integrative analysis of clinical lung tissue samples with the isolation of specific cell populations using laser-microdissection microscopy (LMD). The transcriptomic profile was successfully captured and somatically altered regions marked by histone H3 lysine 4 trimethylation (H3K4me3) were identified in lung cancer. We also observed the differential expressions of cancer-related genes near the altered proximal H3K4me3 regions, while altered distal H3K4me3 regions were overlapped with enhancer activity annotations of cancer regulatory genes. Additionally, proximal tumor-gained promoters were associated with the core components of polycomb repressive complex 2. Our study demonstrates the practical workflow of using LMD on clinical samples for integrative analyses, which improves the overall understanding of genetic and epigenetic dysregulation of malignancy.

Abstract

Our previous integrative study in gastric cancer discovered cryptic promoter activation events that drive the expression of important developmental genes. However, it was unclear if such cancer-associated epigenetic changes occurred in cancer cells or other cell types in bulk tissue samples. An integrative analysis consisting of RNA-Seq and H3K4me3 ChIP-Seq was used. This workflow was applied to a set of matched normal lung tissues and non-small cell lung cancer (NSCLC) tissues, for which the stroma and tumor cell parts could be isolated by laser-microdissection microscopy (LMD). RNA-Seq analysis showed subtype-specific differential expressed genes and enriched pathways in NSCLC. ChIP-Seq analysis results suggested that the proximal altered H3K4me3 regions were located at differentially expressed genes involved in cancer-related pathways, while altered distal H3K4me3 regions were annotated with enhancer activity of cancer regulatory genes. Interestingly, integration with ENCODE data revealed that proximal tumor-gained promoters were associated with EZH2 and SUZ12 occupancies, which are the core components of polycomb repressive complex 2 (PRC2). This study used LMD on clinical samples for an integrative analysis to overcome the tissue heterogeneity problem in cancer research. The results also contribute to the overall understanding of genetic and epigenetic dysregulation of lung malignancy.

Expression and Prognostic Analysis of Integrins in Gastric Cancer

Background

Integrins are involved in the biological process of a variety of cancers, but their importance in the diagnosis and prognosis of gastric cancer (GC) is still unclear. Therefore, this study aimed at exploring the significance of ITG gene expression in GC to evaluate its diagnosis and prognosis.

Methods

GEPIA data were used to evaluate the mRNA expression of ITG genes in GC patients. The prognostic value of these genes was assessed by analyzing their mRNA expression using the Kaplan–Meier curve. The biological function of ITG genes was evaluated by GC tissue sequencing combined with GSEA bioinformatics. Based on the sequencing data, ITGA5 with the largest expression difference was selected for verification, and RT-PCR was used to verify its mRNA expression level in 40 pairs of GC and normal tissues.

Results

ITG (A2, A3, A4, A5, A6, A11, AE, AL, AM, AV, AX, B1, B2, B4, B5, B6, and B8) was highly expressed in GC tissues, while ITGA8 was low, compared with their expression in normal tissues. RNA-seq data shows that ITG (A2, A5, A11, AV, and B1) expression was associated with poor prognosis and overall survival. In addition, combined with the results of GC tissue mRNA sequencing, it was further found that the differentially expressed genes in the ITGs genes. ITGA5 was highly expressed in GC tissues compared with its expression in normal tissues, as evaluated by qRT–PCR (P < 0.001) and ROC (P < 0.001, AUC (95% CI) = 0.747 (0.641–0.851)), and confirmed that ITGA5 expression was a potential diagnostic marker for GC. Bioinformatics analysis revealed that the signaling pathway involved in ITGA5 was mainly enriched in focal adhesion, ECM-receptor interaction, and PI3K-AKT and was mainly involved in biological processes such as cell adhesion, extracellular matrix, and cell migration.

Conclusion

This study suggested that ITGs were associated with the diagnosis and prognosis of GC and discovered the prognostic value and biological role of ITGA5 in GC. Thus, ITGA5 might be used as a potential diagnostic marker for GC.

Characteristics of CD133-Sustained Chemoresistant Cancer Stem-Like Cells in Human Ovarian Carcinoma

Cancer stem cells (CSCs) are considered to be the origin of ovarian cancer (OC) development, recurrence, and chemoresistance. We investigated changes in expression levels of the CSC biomarker, cluster of differentiation 133 (CD133), from primary OC cell lines to induction of CSC-spheres in an attempt to explore the mechanisms related to modulation of stemness, drug resistance, and tumorigenesis in CSCs, thus facilitating the search for new therapeutics for OC. The effect of CD133 overexpression on the induction of CSC properties was evaluated by sphere-forming assays, RT-qPCR, flow cytometry, cell viability assays, and in vivo xenograft experiments. Moreover, the potential signaling molecules that participate in CD133 maintenance of stemness were screened by RNA-sequencing. CD133 expression was upregulated during OCSC induction and chemotherapeutic drug treatment over time, which increased the expressions of stemness-related markers (SOX2, OCT4, and Nanog). CD133 overexpression also promoted tumorigenesis in NOD/SCID mice. Several signalings were controlled by CD133 spheres, including extracellular matrix receptor interactions, chemokine signaling, and Wnt signaling, all of which promote cell survival and cell cycle progression. Our findings suggest that CD133 possesses the ability to maintain functional stemness and tumorigenesis of OCSCs by promoting cell survival signaling and may serve as a potential target for stem cell-targeted therapy of OC.

Integrated Analysis of Prognostic and Immune Associated Integrin Family in Ovarian Cancer

Human integrin receptors are important for cell-cell and cell-matrix adhesion in normal epithelial cells. Emerging evidences have indicated integrin members are involved in cancer development and progression as well. However, the expression patterns and clinical significance of the whole integrin family in ovarian cancer (OC) have not yet been well understood. In the present study, we utilized the public datasets including GEPIA, GEO, ONCOMINE, cBioPortal, Kaplan-Meier Plotter, TIMER databases, to analyze the expression and prognostic value of integrin members in OC. We found ITGA3/B4/B6/B7/B8 were abnormally overexpressed in OC; ITGA6 was good prognosis predictor in OC; ITGA3/ B4/B8 were poor prognosis predictor specially in advanced OC patients; elevated ITGA3/B4 might promote metastasis and elevated ITGA3/B8 might promote platinum resistance of OC; ITGA3 and ITGB4 might synergistically or independently regulate cell adhesion and proliferation; ITGA4/AL/AM/AX/B2/B7 showed strong correlations with various tumor immune infiltrates (TILs), especially with pro-tumor immunes cell types like monocyte, M2 macrophage and exhaustion T cells infiltration; ITGAL/AM/B2/B7 and residing memory CD8+ T cells marker ITGAE were specially associated with early OC patients outcome. Our results implied that ITGA3/B4 were important prognostic markers of advanced OC, ITGAL/AM/ B2/B7 were immune associated prognosis markers of early OC, together they might render important therapeutic targets for OC.

The prognostic value of ITGA and ITGB superfamily members in patients with high grade serous ovarian cancer

Background

Deregulation of integrins signaling had been documented to participate in multiple fundamental biological processes, and the aberrant expression of integrin family members were linked to the prognosis of various cancers. However, the role of integrins in predicting progression and prognosis of ovarian cancer patients are still largely elusive. This study is aimed to explore the prognostic values of ITGA and ITGB superfamily members in high grade serous ovarian cancers (HGSOC).

Methods

GSE26712 dataset was used to determine the differential expression of ITGA and ITGB superfamily member between HGSOC and normal counterparts. The Cancer Genome Altas (TGGA) and GSE9891 datasets were used to determine the prognostic values of ITGA and ITGB superfamily members in HGSOC, followed by the development of nomograms predictive of recurrence free survival (RFS) and overall survival (OS).

Results

ITGA6 and ITGB5 expression were significantly downregulated in HGSOC compared with that in normal counterparts. In contrast, ITGA2, ITGA5, ITGA7, ITGA8, ITGA9, ITGA10, ITGB3, ITGB4, ITGB6, and ITGB8 were all significantly upregulated in HGSOC compared with that in normal counterparts. Both univariable and multivariable analysis indicated that ITGB1 was associated with extended RFS. The ITGB1-related nomogram indicated that ITGB1 had the largest contribution to RFS, followed by FIGO stage and debulking status. The C-index for predicting RFS was 0.55 (95% CI 0.50–0.59) in TCGA dataset (training dataset) and 0.65 (95% CI 0.59–0.72) in GSE9891 dataset (validation dataset), respectively. Regarding OS, ITGB8 was associated with reduced survival suggested by both univariable and multivariable analysis. ITGA7 appeared to be associated with improved survival though without reaching statistical significance. The ITGA7/ITGB8-based nomogram showed that age at initial diagnosis had the largest contribution to OS, followed by ITGB8 and ITGA7 expression. The C-index for predicting OS was 0.65 (95% CI 0.60–0.69) in TCGA dataset (training dataset) and 0.59 (95% CI 0.51–0.66) in GSE9891 dataset (validation dataset), respectively.

Conclusion

In conclusion, ITGB1, ITGA7 and ITGB8 added prognostic value to the traditional clinical risk factors used to assess the clinical outcomes of HGSOC.

Integrin β8 facilitates tumor growth and drug resistance through a Y-box binding protein 1-dependent signaling pathway in bladder cancer

The transmembrane receptors integrins are the bridges for cell-cell or cell-ECM interaction, which is strictly correlated to cancer development in several tumor types. Here, we revealed that integrin β8 serves as a driver to mediate sustained growth of bladder cancer and development of drug resistance. The elevated expression of integrin β8 was observed in highly malignant bladder tumor tissues from patients. The in vitro and in vivo results further indicated that integrin β8 overexpression in Biu87/T24 bladder cancer could mediate and strengthen cell proliferation and resistance to mitomycin C and hydroxycamptothecin. Mechanistically, integrin β8 on the cellular surface might recruit phosphorylated Y-box binding protein 1, leading to the activation of c-Myc and nuclear factor-κB signals. Pharmacological targeting of integrin β8 by Arg-Gly-Asp-Ser efficiently suppressed sustained growth and drug resistance in bladder cancer cells. Our findings identified integrin β8 as a marker of bladder cancer diagnosis and development, and provides an innovative approach for clinical bladder cancer therapy.

Integrin αvβ8 serves as a Novel Marker of Poor Prognosis in Colon Carcinoma and Regulates Cell Invasiveness through the Activation of TGF-β1

Integrin αvβ8 expressed on tumor cells executes crucial regulatory functions during cell adhesion in the tumor microenvironment and supports the activation of TGF-β1. This study aimed to investigate the expression of integrin αvβ8 and its clinical significance in colon cancer, in addition to its influence on the invasion and migration of cancer cells. Our results showed that integrin αvβ8 was an indicator of progression and poor prognosis in patients with colon cancer. Moreover, integrin αvβ8 significantly promoted the invasion and migration of colon cancer cells by the activation of TGF-β1 and upregulation of metalloproteinase-9. Furthermore, suppression of integrin αvβ8 was found to inhibit the growth of colon cancer in vivo. Our results indicate that integrin αvβ8 promotes tumor invasiveness and the migration of colon cancer through TGF-β1 activation and is a potential prognostic biomarker. This study may provide clues to further understand the manner in which the tumor microenvironment mediates the development of colon cancer and develop strategies for novel therapeutic targets in the prevention and treatment of colon cancer.

Expression and prognostic analyses of ITGA11, ITGB4 and ITGB8 in human non-small cell lung cancer

Background

Integrins play a crucial role in the regulation process of cell proliferation, migration, differentiation, tumor invasion and metastasis. ITGA11, ITGB4 and ITGB8 are three encoding genes of integrins family. Accumulative evidences have proved that abnormal expression of ITGA11, ITGB4 and ITGB8 are a common phenomenon in different malignances. However, their expression patterns and prognostic roles for patients with non-small cell lung cancer (NSCLC) have not been completely illustrated.

Methods

We investigated the expression patterns and prognostic values of ITGA11, ITGB4 and ITGB8 in patients with NSCLC through using a series of databases and various datasets, including ONCOMINE, GEPIA, HPA, TCGA and GEO datasets.

Results

We found that the expression levels of ITGA11 and ITGB4 were significantly upregulated in both LUAD and LUSC, while ITGB8 was obviously upregulated in LUSC. Additionally, higher expression level of ITGB4 revealed a worse OS in LUAD.

Conclusion

Our findings suggested that ITGA11 and ITGB4 might have the potential ability to act as diagnostic biomarkers for both LUAD and LUSC, while ITGB8 might serve as diagnostic biomarker for LUSC. Furthermore, ITGB4 could serve as a potential prognostic biomarker for LUAD.

The Impact of Integrin-Mediated Matrix Adhesion on Cisplatin Resistance of W1 Ovarian Cancer Cells

BACKGROUND

Tumor cell binding to the microenvironment is regarded as the onset of therapeutic resistance, referred to as cell adhesion mediated drug resistance (CAM-DR). Here we elucidate whether CAM-DR occurs in ovarian cancer cells and contributes to still-existing cisplatin resistance.

METHODS

Cultivation of W1 and cisplatin-resistant W1CR human ovarian cancer cells on collagen-type I (COL1) was followed by whole genome arrays, MTT assays focusing cisplatin cytotoxicity, and AAS detection of intracellular platinum levels. Expression of cisplatin transporters Ctr1 and MRP2 was analyzed. Mechanistic insight was provided by lentiviral β1-integrin (ITGB1) knockdown, or inhibition of integrin-linked kinase (ILK).

RESULTS

EC₅₀ values of cisplatin cytotoxicity increased twofold when W1 and W1CR cells were cultivated on COL1, associated with significantly diminished intracellular platinum levels. Transporter deregulation could not be detected at mRNA levels but appears partially responsible at protein levels. The ITGB1 knockdown confirms that CAM-DR follows a COL1/ITGB1 signaling axis in W1 cells; thus, a blockade of ILK re-sensitized W1 cells on COL1 for cisplatin. In contrast, CAM-DR adds to cisplatin resistance in W1CR cells independent of ITGB1.

CONCLUSIONS

CAM-DR appears relevant for ovarian cancer cells, adding to existing genetic resistance and thus emerges as a target for sensitization strategies.

A Robust Gene Expression Prognostic Signature for Overall Survival in High-Grade Serous Ovarian Cancer

The objective of this research was to develop a robust gene expression-based prognostic signature and scoring system for predicting overall survival (OS) of patients with high-grade serous ovarian cancer (HGSOC). Transcriptomic data of HGSOC patients were obtained from six independent studies in the NCBI GEO database. Genes significantly deregulated and associated with OS in HGSOCs were selected using GEO2R and Kaplan–Meier analysis with log-rank testing, respectively. Enrichment analysis for biological processes and pathways was performed using Gene Ontology analysis. A resampling/cross-validation method with Cox regression analysis was used to identify a novel gene expression-based signature associated with OS, and a prognostic scoring system was developed and further validated in nine independent HGSOC datasets. We first identified 488 significantly deregulated genes in HGSOC patients, of which 232 were found to be significantly associated with their OS. These genes were significantly enriched for cell cycle division, epithelial cell differentiation, p53 signaling pathway, vasculature development, and other processes. A novel 11-gene prognostic signature was identified and a prognostic scoring system was developed, which robustly predicted OS in HGSOC patients in 100 sampling test sets. The scoring system was further validated successfully in nine additional HGSOC public datasets. In conclusion, our integrative bioinformatics study combining transcriptomic and clinical data established an 11-gene prognostic signature for robust and reproducible prediction of OS in HGSOC patients. This signature could be of clinical value for guiding therapeutic selection and individualized treatment.