Genetic and Immunohistochemical Expression of Integrins ITGAV, ITGA6, and ITGA3 As Prognostic Factor for Colorectal Cancer: Models for Global and Disease-Free Survival

Dual role of mesenchymal stem/stromal cells and their cell-free extracellular vesicles in colorectal cancer

Colorectal cancer (CRC) is one of the main causes of cancer-related deaths. However, the surgical control of the CRC progression is difficult, and in most cases, the metastasis leads to cancer-related mortality. Mesenchymal stem/stromal cells (MSCs) with potential translational applications in regenerative medicine have been widely researched for several years. MSCs could affect tumor development through secreting exosomes. The beneficial properties of stem cells are attributed to their cell-cell interactions as well as the secretion of paracrine factors in the tissue microenvironment. For several years, exosomes have been used as a cell-free therapy to regulate the fate of tumor cells in a tumor microenvironment. This review discusses the recent advances and current understanding of assessing MSC-derived exosomes for possible cell-free therapy in CRC.

A novel class of inhibitors that disrupts the stability of integrin heterodimers identified by CRISPR-tiling-instructed genetic screens

The plasma membrane is enriched for receptors and signaling proteins that are accessible from the extracellular space for pharmacological intervention. Here we conducted a series of CRISPR screens using human cell surface proteome and integrin family libraries in multiple cancer models. Our results identified ITGAV (integrin αV) and its heterodimer partner ITGB5 (integrin β5) as the essential integrin α/β pair for cancer cell expansion. High-density CRISPR gene tiling further pinpointed the integral pocket within the β-propeller domain of ITGAV for integrin αVβ5 dimerization. Combined with in silico compound docking, we developed a CRISPR-Tiling-Instructed Computer-Aided (CRISPR-TICA) pipeline for drug discovery and identified Cpd_AV2 as a lead inhibitor targeting the β-propeller central pocket of ITGAV. Cpd_AV2 treatment led to rapid uncoupling of integrin αVβ5 and cellular apoptosis, providing a unique class of therapeutic action that eliminates the integrin signaling via heterodimer dissociation. We also foresee the CRISPR-TICA approach to be an accessible method for future drug discovery studies.

Silencing of integrin subunit α3 inhibits the proliferation, invasion, migration and autophagy of esophageal squamous cell carcinoma cells

Esophageal squamous cell carcinoma (ESCC) is a deadly disease that seriously affects global public health. The aim of the present study was to explore the role of integrin subunit α3 (ITGA3) in ESCC and investigate its detailed molecular mechanisms. Using reverse transcription–quantitative PCR (RT-qPCR) and western blotting, the mRNA and protein expression of ITGA3 in cell lines was detected. In addition, a series of cellular biological experiments, including Cell Counting Kit-8, wound-healing, Transwell and TUNEL assays, were used to evaluate proliferation, migration, invasion and apoptosis, respectively. Furthermore, western blotting was used to measure the expression of corresponding proteins. ITGA3 was found to be upregulated in ESCC cell lines (ECA109 and TE1). It was also found that ITGA3 silencing inhibited the proliferation, migration, invasion and autophagy of ECA109 and TE1 cells but promoted their apoptosis. In addition, ITGA3 silencing was found to inhibit the FAK/PI3K/AKT signaling pathway. In conclusion, ITGA3 knockdown suppressed cell proliferation, invasion, migration and autophagy in ECA109 and TE1 cells, suggesting that ITGA3 may be a potential therapeutic target for the treatment of ESCC.

Transcriptomic analysis reveals high ITGB1 expression as a predictor for poor prognosis of pancreatic cancer

Transcriptomic analysis of cancer samples helps identify the mechanism and molecular markers of cancer. However, transcriptomic analyses of pancreatic cancer from the Japanese population are lacking. Hence, in this study, we performed RNA sequencing of fresh and frozen pancreatic cancer tissues from 12 Japanese patients to identify genes critical for the clinical pathology of pancreatic cancer among the Japanese population. Additionally, we performed immunostaining of 107 pancreatic cancer samples to verify the results of RNA sequencing. Bioinformatics analysis of RNA sequencing data identified ITGB1 (Integrin beta 1) as an important gene for pancreatic cancer metastasis, progression, and prognosis. ITGB1 expression was verified using immunostaining. The results of RNA sequencing and immunostaining showed a significant correlation (r = 0.552, p = 0.118) in ITGB1 expression. Moreover, the ITGB1 high-expression group was associated with a significantly worse prognosis (p = 0.035) and recurrence rate (p = 0.028). We believe that ITGB1 may be used as a drug target for pancreatic cancer in the future.

Integrin α3/α6 and αV are implicated in ADAM15-activated FAK and EGFR signalling pathway individually and promote non-small-cell lung cancer progression

Disintegrin-metalloproteinase 15(ADAM15), a member of disintegrin metalloproteinases (ADAMs), plays important roles in various cancer types. However, the underlying ADAM15 functioning in lung cancer is still unclear. In the present study, we find that ADAM15 regulates the epidermal growth factor receptor/focal adhesion kinase (EGFR/FAK) signalling pathway by interactions with integrins. Integrin αV is involved in ADAM15-mediated FAK signalling. Further, we find that ADAM15 and CD151 were co-expressed, and the presence of ADAM15 affected the integrin α3/α6-related EGFR signalling pathway by cooperating with CD151. In addition, we also prove the effect of ADAM15 on proliferation in nude mice. Finally, we show that ADAM15 is a direct target of miR-204-5p by luciferase reporter assays, qRT-PCR and western blot analyses. Our findings provide molecular and cellular evidence that ADAM15 promotes cell proliferation and metastasis in NSCLC, which might provide a potential target for NSCLC treatment.

Machine learning with imaging features to predict the expression of ITGAV, which is a poor prognostic factor derived from transcriptome analysis in pancreatic cancer

Radiogenomics has attracted attention for predicting the molecular biological characteristics of tumors from clinical images, which are originally a collection of numerical values, such as computed tomography (CT) scans. A prediction model using genetic information is constructed using thousands of image features extracted and calculated from these numerical values. In the present study, RNA sequencing of pancreatic ductal adenocarcinoma (PDAC) tissues from 12 patients was performed to identify genes useful in evaluating clinical pathology, and 107 PDAC samples were immunostained to verify the obtained findings. In addition, radiogenomics analysis of gene expression was performed by machine learning using CT images and constructed prediction models. Bioinformatics analysis of RNA sequencing data identified integrin αV (ITGAV) as being important for clinicopathological factors, such as metastasis and prognosis, and the results of sequencing and immunostaining demonstrated a significant correlation (r=0.625, P=0.039). Notably, the ITGAV high‑expression group was associated with a significantly worse prognosis (P=0.005) and recurrence rate (P=0.003) compared with the low‑expression group. The ITGAV prediction model showed some detectability (AUC=0.697), and the predicted ITGAV high‑expression group was also associated with a worse prognosis (P=0.048). In conclusion, radiogenomics predicted the expression of ITGAV in pancreatic cancer, as well as the prognosis.

The therapeutic potential of stem cell-derived exosomes in the ulcerative colitis and colorectal cancer

BACKGROUND

Mesenchymal stem cells (MSCs) therapy is a novel treatment strategy for cancer and a wide range of diseases with an excessive immune response such as ulcerative colitis (UC), due to its powerful immunomodulatory properties and its capacity for tissue regeneration and repair. One of the promising therapeutic options can focus on MSC-secreted exosomes (MSC-Exo), which have been identified as a type of paracrine interaction. In light of a wide variety of recent experimental studies, the present review aims to seek the recent research advances of therapies based on the MSC-Exo for treating UC and colorectal cancer (CRC).

METHODS

A systematic literature search in MEDLINE, Scopus, and Google Scholar was performed from inception to December 2021 using the terms [("colorectal cancer" OR "bowel cancer" OR "colon cancer" OR "rectal cancer") AND (exosome) AND (stem cell) AND ("inflammatory bowel disease" OR "Crohn's disease" OR "colitis")] in titles and abstracts.

FINDINGS

Exosomes derived from various sources of MSCs, including human umbilical cord-derived MSCs (hUC-MSCs), human adipose-derived MSCs (hAD-MSCs), human bone marrow-derived MSCs (hBM-MSCs), and olfactory ecto-MSCs (OE-MSCs), have shown the protective role against UC and CRC. Exosomes from hUC-MSCs, hBM-MSCs, AD-MSCs, and OE-MSCs have been found to ameliorate the experimental UC through suppressing inflammatory cells including macrophages, Th1/Th17 cells, reducing the expression of proinflammatory cytokines, as well as inducing the anti-inflammatory function of Treg and Th2 cells and enhancing the expression of anti-inflammatory cytokines. In addition, hBM-MSC-Exo and hUC-MSC-Exo containing tumor-suppressive miRs (miR-3940-5p/miR-22-3p/miR-16-5p) have been shown to suppress proliferation, migration, and invasion of CRC cells via regulation of RAP2B/PI3K/AKT signaling pathway and ITGA2/ITGA6.

KEY MESSAGES

The MSC-Exo can exert beneficial effects on UC and CRC through two different mechanisms including modulating immune responses and inducing anti-tumor responses, respectively.

Mesenchymal Stem Cell-Derived Exosomal microRNA-3940-5p Inhibits Colorectal Cancer Metastasis by Targeting Integrin α6

BACKGROUND

Exosomes are potential tools for disease control by regulating intercellular communication through carrying proteins and RNAs between cells or remote organs. Exosome activities have aroused wide concerns in cancer biology and malignancy control.

AIMS

This study was performed to explore the roles of mesenchymal stem cell (MSC)-derived exosomes in colorectal cancer (CRC) progression.

METHODS

MSC-exosomal microRNAs (miRNAs) in CRC tissues were analyzed, and aberrantly expressed miRNAs in CRC tissues were obtained from the data available on the GEO database. Altered expression of miR-3940-5p was introduced to identify its role in CRC invasion and metastasis in both cell and animal models. The binding relationship between miR-3940-5p and Integrin alpha6 (ITGA6) was predicted on TargetScan and validated through a luciferase assay. The effects of ITGA6 on CRC were figured out.

RESULTS

MSC-derived exosomes carried miR-3940-5p into CRC cells. Up-regulation of miR-3940-5p inhibited epithelial-mesenchymal transition (EMT) and invasion of CRC cells, and suppressed the tumor metastasis and growth in vivo. miR-3940-5p was found to directly bind to ITGA6. Overexpression of ITGA6 promoted CRC cell invasion and EMT and tumor progression through upregulating the transforming growth factor-beta1 (TGF-β1) signaling. A TGF-β1-specific antagonist, Disitertide, blocked the functions of ITGA6 both in vivo and in vitro.

CONCLUSION

MSC-exosomal miR-3940-5p inhibits invasion and EMT of CRC cells as well as growth and metastasis of tumors through targeting ITGA6 and the following TGF-β1 inactivation. This study may provide novel insights into exosome-based treatment for CRC.

The clinical relevance of gene expression based prognostic signatures in colorectal cancer

Colorectal cancer (CRC) is one of the most prevalent cancers, with more than one million new cases every year. In the last few decades, several advancements in therapeutic and preventative levels have reduced the mortality rate, but new biomarkers are required for improved prognosis. The alterations at the genetic and epigenetic level have been recognized as major players in tumorigenesis. The products of gene expression in the form of mRNA, microRNA, and long-noncoding RNA, have started to emerge as important regulatory molecules, playing an important role in cancer. Gene-expression based prognostic risk scores, which quantify and compare their expression, have emerged as promising biomarkers with enormous clinical value. These composite multi-gene models in which more than one gene is used to predict prognosis have been shown to be significantly effective in identifying patients with multiple clinico-pathological risks like overall mortality, response to chemotherapy, risk of metastasis, etc. The advent of microarray and advanced sequencing technologies have led to the generation of large datasets like TCGA (The Cancer Genome Atlas) and GEO (Gene Expression Omnibus), which have fueled the search for new biomarkers. Continuous evaluation of these candidate biomarkers in clinical settings is promising to improve the management of CRC. These composite gene signatures provide potential in identifying high-risk patients, which might help clinicians to better manage these patients and design appropriate personalized therapeutic interventions. In this review, we emphasize on composite prognostic scores from diverse resources with clinical utility in CRC.

Hematopoietic Gene Expression Regulation Through m6A Methylation Predicts Prognosis in Stage III Colorectal Cancer

Background

Methylation of N6 adenosine (m⁶A) plays important regulatory roles in diverse biological processes. The purpose of this research was to explore the potential mechanism of m⁶A modification level on the clinical outcome of stage III colorectal cancer (CRC).

Methods

Gene set variation analysis (GSVA) and gene set enrichment analysis (GSEA) were adopted to reveal the signal pathway which was most likely affected by m⁶A methylation. The linear models for microarray data (LIMMA) method and the least absolute shrink-age and selection operator (LASSO) Cox regression model were used to identify the signature. The signature can sensitively separate the patients into high and low risk indicating the relapse-free survival (RFS) time based on time-dependent receiver operating characteristic (ROC) analysis. Then, the multi-gene signature was validated in GSE14333 and the Cancer Genome Atlas (TCGA) cohort. The number of the samples in GSE14333 and TCGA cohort are 63 and 150. Finally, two nomograms were set up and validated to predict prognosis of patients with stage III CRC.

Results

The hematopoietic cell lineage (HCL) signaling pathway was disclosed through GSEA and GSVA. Seven HCL-related genes were determined in the LASSO model to construct signature, with AUC 0.663, 0.708, and 0.703 at 1-, 3-, and 5-year RFS, respectively. Independent datasets analysis and stratification analysis indicated that the HCL-related signature was reliable in distinguishing high- and low-risk stage III CRC patients. Two nomograms incorporating the signature and pathological N stage were set up, which yielded good discrimination and calibration in the predictions of prognosis for stage III CRC patients.

Conclusions

A novel HCL-related signature was developed as a predictive model for survival rate of stage III CRC patients. Nomograms based on the signature were advantageous to facilitate personalized counseling and treatment in stage III CRC.

Expression and Prognostic Analyses of ITGA3, ITGA5, and ITGA6 in Head and Neck Squamous Cell Carcinoma

BACKGROUND The landscape of head and neck cancers has changed with improvements in standard therapy; however, it is necessary to exploit advanced genomic approaches to identify novel diagnostic and prognostic biomarkers for head and neck squamous cell carcinoma (HNSC). ITGA3, ITGA5, and ITGA6, members of the integrin family of proteins, play active roles in cytoskeletal organization and cell migration, proliferation, and survival. However, the expression patterns and prognostic values of ITGA3, ITGA5, and ITGA6 in head and neck squamous cell carcinoma remain unclear. MATERIAL AND METHODS Different expression patterns and prognostic values of ITGA3, ITGA5, and ITGA6 were analyzed in patients with HNSC using various databases, including ONCOMINE, GEPIA, TIMER, HPA, Kaplan-Meier Plotter, GEO, and TCGA. RESULTS Expression levels of ITGA3, ITGA5, and ITGA6 were substantially increased in patients with HNSC. Additionally, higher expression levels of ITGA3, ITGA5, and ITGA6 were associated with worse overall survival in patients with HNSC, and higher levels of ITGA3 correlated with a worse relapse-free survival. CONCLUSIONS ITGA3, ITGA5, and ITGA6 are potential diagnostic and prognostic biomarkers for HNSC. In particular, IGTA5 might be used as a significant independent prognostic factor in this cancer.

Development and application of two novel monoclonal antibodies against overexpressed CD26 and integrin α3 in human pancreatic cancer

Monoclonal antibody (mAb) technology is an excellent tool for the discovery of overexpressed cell surface tumour antigens and the development of targeting agents. Here, we report the development of two novel mAbs against CFPAC-1 human pancreatic cancer cells. Using ELISA, flow cytometry, immunoprecipitation, mass spectrometry, Western blot and immunohistochemistry, we found that the target antigens recognised by the two novel mAbs KU44.22B and KU44.13A, are integrin α3 and CD26 respectively, with high levels of expression in human pancreatic and other cancer cell lines and human pancreatic cancer tissue microarrays. Treatment with naked anti-CD26 mAb KU44.13A did not have any effect on the growth and migration of cancer cells nor did it induce receptor downregulation. In contrast, treatment with anti-integrin α3 mAb KU44.22B inhibited growth in vitro of Capan-2 cells, increased migration of BxPC-3 and CFPAC-1 cells and induced antibody internalisation. Both novel mAbs are capable of detecting their target antigens by immunohistochemistry but not by Western blot. These antibodies are excellent tools for studying the role of integrin α3 and CD26 in the complex biology of pancreatic cancer, their prognostic and predictive values and the therapeutic potential of their humanised and/or conjugated versions in patients whose tumours overexpress integrin α3 or CD26.

Integrin subunit alpha V promotes growth, migration, and invasion of gastric cancer cells

Integrin subunit alpha V (ITGAV), a member of integrin family of extracellular matrix receptors, is involved in many types of cancer. In this study, the expression levels, clinical features and prognosis of ITGAV in gastric cancer (GC) patients were investigated, and the functional roles of ITGAV were also investigated. Cell Counting Kit-8 (CCK-8) assay was performed to examine the proliferation of GC cells. Transwell assays and wound-healing assays were conducted to explore the effect of ITGAV expression on GC cell migration and invasion. We found that ITGAV was overexpressed in both GC tissues and GC cells. ITGAV expression was positively correlated with lymph node metastasis and TNM stage of GC. High expression of ITGAV was associated with shorter overall survival (OS) and disease-free survival (DFS). Interestingly, the downregulation of ITGAV resulted in suppression of proliferation, migration, and invasion in GC cells. In conclusion, ITGAV is overexpressed in gastric cancer and is associated with poorer prognostic outcomes. ITGAV may serve as an important prognostic marker for GC staging and progression.

IL-32γ suppresses lung cancer stem cell growth via inhibition of ITGAV-mediated STAT5 pathway

The cancer stem cells (CSCs) are thought to be responsible for cancer initiation, recurrence, and metastasis via a multifactorial process. IL-32γ has been known to inhibit several tumor developments. However, the role of IL-32γ in CSCs is unknown. The role of IL-32γ on tumor development was assessed in IL-32γ transgenic (Tg) mice allograft and xenograft model. In the in vitro assay, we analyzed CSC growth and apoptosis in cells with IL-32γ overexpression by cell viability assay and tumor-sphere formation assay. In addition, expression of cell proliferation, apoptosis markers, and signaling molecules was determined by western blot analysis. IL-32γ suppressed CD133+ CSC-induced allograft model in IL-32γ Tg mice and xenograft model. Tumor-sphere formation and cell viability assay revealed a greater inhibition of CSC proliferation and antineoplastic activity of IL-32γ in CD133+ CSCs as compared with normal cancer cells. The inhibitory effects of IL-32γ on tumor development were associated with inhibition of the STAT5 pathway. In addition, inhibition of STAT5 increased cleavage of caspase-3, but suppressed CD133 expression and colony formation. Web-based gene network analysis showed that IL-32 is correlated with ITGAV, an integrin gene. Our result revealed that knockdown of ITGAV by siRNA inhibited the phosphorylation of STAT5. Moreover, we identified that ITGAV overexpression reversed the effect of IL-32γ on phosphorylation of STAT5 and the expression of CD133. Our results demonstrate that IL-32γ negatively regulates CD133+ CSC proliferation and tumor development and suggest that IL-32γ has great potential for use in the treatment of cancer progression.

The Open Chromatin Landscape of Non-Small Cell Lung Carcinoma

Non-small cell lung carcinoma (NSCLC) is a major cancer type whose epigenetic alteration remains unclear. We analyzed open chromatin data with matched whole-genome sequencing and RNA-seq data of 50 primary NSCLC cases. We observed high interpatient heterogeneity of open chromatin profiles and the degree of heterogeneity correlated to several clinical parameters. Lung adenocarcinoma and lung squamous cell carcinoma (LUSC) exhibited distinct open chromatin patterns. Beyond this, we uncovered that the broadest open chromatin peaks indicated key NSCLC genes and led to less stable expression. Furthermore, we found that the open chromatin peaks were gained or lost together with somatic copy number alterations and affected the expression of important NSCLC genes. In addition, we identified 21 joint-quantitative trait loci (joint-QTL) that correlated to both assay for transposase accessible chromatin sequencing peak intensity and gene expression levels. Finally, we identified 87 regulatory risk loci associated with lung cancer-related phenotypes by intersecting the QTLs with genome-wide association study significant loci. In summary, this compendium of multiomics data provides valuable insights and a resource to understand the landscape of open chromatin features and regulatory networks in NSCLC. SIGNIFICANCE: This study utilizes state of the art genomic methods to differentiate lung cancer subtypes.See related commentary by Bowcock, p. 4808.

In Silico Transcriptomic Analysis of Wound-Healing-Associated Genes in Malignant Pleural Mesothelioma

Background and objectives: Malignant pleural mesothelioma (MPM) is a devastating malignancy with poor prognosis. Reliable biomarkers for MPM diagnosis, monitoring, and prognosis are needed. The aim of this study was to identify genes associated with wound healing processes whose expression could serve as a prognostic factor in MPM patients. Materials and Methods: We used data mining techniques and transcriptomic analysis so as to assess the differential transcriptional expression of wound-healing-associated genes in MPM. Moreover, we investigated the potential prognostic value as well as the functional enrichments of gene ontologies relative to microRNAs (miRNAs) of the significantly differentially expressed wound-healing-related genes in MPM. Results: Out of the 82 wound-healing-associated genes analyzed, 30 were found significantly deregulated in MPM. Kaplan–Meier analysis revealed that low ITGAV gene expression could serve as a prognostic factor favoring survival of MPM patients. Finally, gene ontology annotation enrichment analysis pointed to the members of the hsa-miR-143, hsa-miR-223, and the hsa-miR-29 miRNA family members as important regulators of the deregulated wound healing genes. Conclusions: 30 wound-healing-related genes were significantly deregulated in MPM, which are potential targets of hsa-miR-143, hsa-miR-223, and the hsa-miR-29 miRNA family members. Out of those genes, ITGAV gene expression was a prognostic factor of overall survival in MPM. Our results highlight the role of impaired tissue repair in MPM development and should be further validated experimentally.

Ilex hainanensis Merr targets ITGAV to suppress the proliferation and metastasis of osteosarcoma cells

Background: Osteosarcoma (OS) is the most common primary malignant bone tumor. Hence, there is an urgent need to identify effective and safe therapeutic agents against OS. It has been reported that Ilex hainanensis Merr (IME) possesses antitumor properties. Integrin subunit alpha V (ITGAV) is important for the diagnosis, treatment, and prognosis of tumors.

Purpose: The objective of this study was to whether IME can play a role in the treatment of osteosarcoma by regulating ITGAV.

Methods: Western blot and real-time PCR were used to detect the expression of ITGAV in non-tumorous tissues, osteosarcoma tissues, and metastatic tumors. The expression of ITGAV in MG63, U2OS, and hFOB1. A total of 19 cells was determined through Western blotting and real-time PCR. The expression of ITGAV in OS cells treated with different concentrations of DDP was determined through Western blotting. Agter transfecting with control or si-ITGAV, and subsequently treated with control or 5 μmol/L DDP, MTT assay and transwell assay were used to detect the proliferaion and migration of cells. Western blot was used to detect the expression of ITGAV in cells treated with different concentrations of IME and MTT assay and transwell assay were used to detect the proliferaion and migration of cells. MG63 and U2OS cells were treated with control, 5 μmol/L DDP, 25 μmol/L IME, or 5 μmol/L DDP combined with 25 μmol/L IME, the expression of ITGAV was determined through Western blotting and real-time PCR. MTT assay and transwell assay were used to detect the proliferation and migration of cells. Inhibitory effect of IME on lung metastasis of osteosarcoma in vivo.

Results: ITGAV was highly expressed in tumors, with the highest expression found in metastatic tumors and higher in OS cells. A low concentration of DDP (5 μmol/L) inhibited the expression of ITGAV. However, ITGAV may be related to the development of resistance to DDP. Silencing of ITGAV downregulates the proliferation and migration of OS cells as the effect of low-concentration DDP (5 μmol/L). IME inhibited the proliferation and migration of MG63 and U2OS cells in a concentration-dependent manner and decreased the expression of ITGAV. MTT and Transwell assays showed that 25 μmol/L IME and 5 μmol/L DDP exhibited similar inhibitory effects on the proliferation and migration of OS cells. The combination of IME with DDP resulted in the amplification of these inhibitory effects. Both DDP and IME downregulated the expression of ITGAV, and the inhibition of ITGAV was amplified by the combination of IME with DDP. In-vivo studies have shown that IME and DDP, independently or in combination, may significantly inhibit the metastasis of OS to the lungs.

Conclusion: IME may reduce the resistance of OS cells to DDP to some extent.

ITGA3 serves as a diagnostic and prognostic biomarker for pancreatic cancer

Background and objective: ITGA3 is a cell surface adhesion protein that interacts with extracellular matrix proteins which function in cancer metastasis. We examined the relationship of pancreatic ITGA3 expression with the clinical and pathological characteristics of patients with pancreatic cancer. Methods: Data mining was used to analyze pancreatic cancer data from The Cancer Genome Atlas database. A Chi squared test was used to evaluate correlations of ITGA3 expression with clinical and pathological parameters. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic performance of ITGA3 expression. Survival analysis and Cox regression analysis were used to examine the prognostic value of ITGA3 expression. Gene Set Enrichment Analysis (GSEA) was used to identify signaling pathways related to ITGA3 expression. Results: Pancreatic expression of ITGA3 was greater in patients with pancreatic cancer than those without cancer, and was also associated with histological type, histological grade, stage, T classification, vital status, and relapse. ROC analysis indicated that ITGA3 had significant diagnostic value, in that high expression correlated with poor overall survival and relapse-free survival, especially in patients with early-stage cancer. Cox analysis indicated that high ITGA3 expression was an independent prognostic factor for pancreatic cancer. GSEA analysis identified 9 signaling pathways that were enriched in the presence of high ITGA3 expression. Conclusion: Expression of ITGA3 can be used as a diagnostic and prognostic biomarker in pancreatic cancer.

ITGA6 and RPSA synergistically promote pancreatic cancer invasion and metastasis via PI3K and MAPK signaling pathways

Pancreatic cancer is one of the most malignant tumors. Invasion and metastasis can occur in the early stage of pancreatic cancer, contributing to the poor prognosis. Accordingly, in this study, we evaluated the molecular mechanisms underlying invasion and metastasis. Using mass spectrometry, we found that Integrin alpha 6 (ITGA6) was more highly expressed in a highly invasive pancreatic cancer cell line (PC-1.0) than in a less invasive cell line (PC-1). Through in vitro and in vivo experiments, we observed significant decreases in invasion and metastasis in pancreatic cancer cells after inhibiting ITGA6. Based on data in TCGA, high ITGA6 expression significantly predicted poor prognosis. By using Co-IP combined mass spectrometry, we found that ribosomal protein SA (RPSA), which was also highly expressed in PC-1.0, interacted with ITGA6. Similar to ITGA6, high RPSA expression promoted invasion and metastasis and indicated poor prognosis. Interestingly, although ITGA6 and RPSA interacted, they did not mutually regulate each other. ITGA6 and RPSA affected invasion and metastasis via the PI3K and MAPK signaling pathways, respectively. Inhibiting ITGA6 significantly reduced the expression of p-AKT, while inhibiting RPSA led to the downregulation of p-ERK1/2. Compared with the inhibition of ITGA6 or RPSA alone, the downregulation of both ITGA6 and RPSA weakened invasion and metastasis to a greater extent and led to the simultaneous downregulation of p-AKT and p-ERK1/2. Our research indicates that the development of drugs targeting both ITGA6 and RPSA may be an effective strategy for the treatment of pancreatic cancer.

Expression of integrin α-6 is associated with multi drug resistance and prognosis in ovarian cancer

Ovarian cancer is a serious threat to women's health. Multidrug resistance is a major cause of post-treatment relapse, metastasis, and even mortality. This characteristic severely restricts the survival of patients with ovarian cancer. Integrin α-6 (ITGA6) is a member of the adhesion molecule family that conducts signals through interactions between the extracellular domain and the matrix, serving important roles in cell adhesion-mediated drug resistance, which is considered to have a critical function in ovarian cancer drug resistance. The association between ITGA6 and ovarian cancer multidrug resistance has been investigated only rarely, to the best of our knowledge. Using RT-qPCR and immunohistochemistry, it was identified that ITGA6 is a central drug resistance gene, and that its expression was upregulated in cisplatin-resistant SKOV3 (SKOV3/DDP2), cisplatin-resistant A2780 (A2780/DDP) cells, and in 54 cases of drug-resistant tissues, as compared with in the controls. Furthermore, bioinformatics and text mining performed by Coremine Medical (http://www.coremine.com/medical/#search) confirmed that ITGA6 was significantly associated with ovarian cancer and drug resistance. Additionally, the high expression of ITGA6 is associated with a poor outcome. The present study provides the basis for further understanding the role of ITGA6 in the regulation of drug resistance in ovarian cancer, and demonstrates that it could be a potential marker for the prognosis of ovarian cancer.

Proteomic phenotyping of metastatic melanoma reveals putative signatures of MEK inhibitor response and prognosis

BACKGROUND

Genotyping of melanomas is used to identify patients for treatment with BRAF and MEK inhibitors, but clinical responses are highly variable. This study investigated the utility of protein expression phenotyping to provide an integrated assessment of gene expression programs in BRAF/NRAS melanoma which would be useful for prognosis and may predict response to MEK inhibition.

METHODS

Mass spectrometry profiling of early passage cell lines established from Stage III cutaneous melanomas was conducted. Basal protein expression was correlated with in vitro response to the MEK inhibitor, selumetinib. Protein expression in a cohort of 32 drug naïve BRAF/NRAS metastatic melanoma specimens was examined. The prognostic utility of a subset of these proteins and mRNA transcripts from a separate cohort was determined.

RESULTS

Unsupervised analysis of basal cell line protein abundances delineated response to selumetinib, but BRAF/NRAS genotype did not. Resistance was associated with functions including cell motility, cell adhesion and cytoskeletal organization. Several of these response biomarkers were observed in lymph node biospecimens and correlated with melanoma-specific survival. Loss of ICAM-1 protein and mRNA expression was a strong prognosticator of diminished survival in BRAF/NRAS mutant melanoma.

CONCLUSIONS

These results demonstrate the utility of proteomic phenotyping to identify both putative biomarkers of response to MEK inhibition and prognostication associated with metastatic melanoma.

Comprehensive analysis of metastasis-related genes reveals a gene signature predicting the survival of colon cancer patients

Objective

The mechanism underlying colon cancer metastasis remain unclear. This study aimed to elucidate the genes alteration during the metastasis of colon cancer and identify genes that crucial to the metastasis and survival of colon cancer patients.

Methods

The dataset of primary and metastasis tissue of colon cancer, and dataset of high and low metastasis capability of colon cancer cells were selected as training cohort, and the overlapped differentially expressed genes (DEGs) were screened from the training cohort. The functional enrichment analysis for the overlapped DEGs was performed. The prognostic value of overlapped DEGs were analyzed in The Cancer Genome Atlas dataset, and a gene signature was developed using genes that related to the overall survival (OS). The prognostic value of the gene signature was further confirmed in a validation cohort.

Results

A total of 184 overlapped DEGs were screened from the training cohort. Functional enrichment analysis revealed the significant gene functions and pathways of the overlapped DEGs. Four hub genes (3-oxoacid CoA-transferase 1, actinin alpha 4, interleukin 8, integrin subunit alpha 3) were identified using protein–protein network analysis. Six genes (aldehyde dehydrogenase 2, neural precursor cell expressed, developmentally down-regulated 9, filamin A, lamin B receptor, twinfilin actin binding protein 1, serine and arginine rich splicing factor 1) were closely related to the OS of colon cancer patients. A gene signature was developed using these six genes based on their risk score, and the validation cohort indicated that the prognostic value of this gene signature was high in the prediction of colon cancer patients.

Conclusions

Our study demonstrates a gene profiles related to the metastasis of colon cancer, and identify a six-gene signature that acts as an independent biomarker on the prognosis of colon cancer.

Identification of ITGA3 as an Oncogene in Human Tongue Cancer via Integrated Bioinformatics Analysis

Human tongue cancer (TC) is an aggressive malignancy with a very poor prognosis. There is an urgent need to elucidate the underlying molecular mechanisms involved in TC progression. mRNA expression profiles play a vital role in the exploration of cancer-related genes. Therefore, the purpose of our study was to identify the progression associated candidate genes of TC by bioinformatics analysis. Five microarray datasets of TC samples were downloaded from the Gene Expression Omnibus (GEO) database and the data of 133 TC patients were screened from The Cancer Genome Atlas (TCGA) head and neck squamous cell carcinoma (HNSC) database. The integrated analysis of five microarray datasets and the RNA sequencing data of TC samples in TCGA-HNSC was performed to obtain 1023 overlapping differentially expressed genes (DEGs) in TC and adjacent normal tissue (ANT) samples. Next, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was conducted to enrich the significant pathways of the 1023 DEGs and PI3KAkt signaling pathway (P=0.011) was selected to be the candidate pathway. A total of 23 DEGs with |log2 fold change (FC)| ≥1.0 in phosphatidylinositol 3-kinase-serine/threonine kinase (PI3K-Akt) signaling pathway were subjected to survival analysis of 125 eligible TC samples in TCGA database, indicating increased integrin-α3 gene (ITGA3) expression was significantly associated with poorer prognosis. Taken together, our study suggested ITGA3 may facilitate the development of TC via activating PI3K-Akt signaling pathway.

SPARC: As a prognostic biomarker in rectal cancer patients treated with chemo-radiotherapy

BACKGROUND

The aim of this study is to search the prognostic value of SPARC expression in rectum cancer cases receiving postoperative radiotherapy.

METHODS

Forty three rectal cancer patients are recruited to this retrospective study. All patients received postoperative radiotherapy which the median dose was 5040 cGy and concomitant chemotherapy. Samples taken from their paraffin blocks were examined with immunohistochemical procedures.

RESULTS

When the association between SPARC expression and the clinicopathological feature was examined, there was a significant association between age and expression levels. Overall survival of patients with low expression was found to be 67 months whereas the overall survival of the patients with high expression was 32 months and the difference was statistically significant. Time to local recurrence of patients with low expression was found to be 74 months whereas time to local recurrence of the patients with high expression was 31 months. Progression free survival of the patients with low expression and high expression were 67 months and 32 months, respectively. In multivariate Cox regression analyses, high expression of SPARC was found to be associated with a statistically significant shorter overall survival and progression free survival.

CONCLUSIONS

High expression of SPARC is related to worse prognosis in rectal cancer patients.

STROBE-compliant integrin through focal adhesion involve in cancer stem cell and multidrug resistance of ovarian cancer

Cancer stem cells (CSCs) are considered to be the root of carcinoma relapse and drug resistance in ovarian cancer. Hunting for the potential CSC genes and explain their functions would be a feasible strategy to meet the challenge of the drug resistance in ovarian cancer. In this study, we performed bioinformatic approaches such as biochip data extraction and pathway enrichment analyses to elucidate the mechanism of the CSC genes in regulation of drug resistance. Potential key genes, integrins, were identified to be related to CSC in addition to their associations with drug resistance and prognosis in ovarian cancer. A total of 36 ovarian CSC genes involved in regulation of drug resistance were summarized, and potential drug resistance-related CSC genes were identified based on 3 independent microarrays retrieved from the Gene Expression Omnibus (GEO) Profiles. Pathway enrichment of CSC genes associated with drug resistance in ovarian cancer indicated that focal adhesion signaling might play important roles in CSC genes-mediated drug resistance. Integrins are members of the adhesion molecules family, and integrin subunit alpha 1, integrin subunit alpha 5, and integrin subunit alpha 6 (ITGA6) were identified as central CSC genes and their expression in side population cells, cisplatin-resistant SKOV3 (SKOV3/DDP2) cells, and cisplatin-resistant A2780 (A2780/DDP) cells were dysregulated as measured by real-time quantitative polymerase chain reaction. The high expression of ITGA6 in 287 ovarian cancer patients of TCGA cohort was significantly associated with poorer progression-free survival. This study provide the basis for further understanding of CSC genes in regulation of drug resistance in ovarian cancer, and integrins could be a potential biomarker for prognosis of ovarian cancer.

Serum and tissue markers in colorectal cancer: State of art

Colorectal cancer (CRC) represents one of the most commonly diagnosed cancers worldwide. It is the second leading cause of cancer death in Western Countries. In the last decade, the survival of patients with metastatic CRC has improved dramatically. Due to the advent of new drugs (irinotecan and oxaliplatin) and target therapies (i.e. bevacizumab, cetuximab, panitumab, aflibercept and regorafenib), the median overall survival has risen from about 12 mo in the mid nineties to 30 mo recently. Molecular studies have recently widened the opportunity for testing new possible markers, but actually, only few markers can be recommended for practical use in clinic. In the next future, the hope is to have a complete panel of clinical biomarkers to use in every setting of CRC disease, and at the same time: 1) to receive information about prognostic significance by their expression and 2) to be oriented in the choice of the adequate treatment. Moreover, molecular analyses have shown that the natural history of all CRCs is not the same. Individual patients with same stage tumors may have different long-term prognosis and response to therapy. In addition, some prognostic variables are likely to be more important than others. Here we review the role of serum and tissue markers according to the recently published English literature. This paper is an extension of the article "Biological and clinical markers in colorectal cancer: state of art" by Cappellani A published in Jan 2010.

A seven-gene signature predicts overall survival of patients with colorectal cancer

Colorectal cancer (CRC) is a major cause of global cancer mortality. Gene expression profiles can help predict prognosis of patients with CRC. In most of previous studies, disease recurrence was analyzed as the survival endpoint. Thus we aim to build a robust gene signature for prediction of overall survival (OS) in patients with CRC. Fresh frozen CRC tissues from 64 patients were analyzed using Affymetrix HG-U133plus 2.0 gene arrays. By performing univariate survival analysis, 6487 genes were found to be associated with the OS in our cohort. KEGG analysis revealed that these genes were mainly involved in pathways such as endocytosis, axon guidance, spliceosome, Wnt signalling and ubiquitin mediated proteolysis. A seven-gene signature was further selected by a robust likelihood-based survival modelling approach. The prognostic model of seven-gene signature (NHLRC3, ZDHHC21, PRR14L, CCBL1, PTPRB, PNPO, and PPIP5K2) was constructed and weighted by regression coefficient, which divided patients into high- and low-risk groups. The OS for patients in high-risk group was significantly poorer compared with patients in low-risk group. Moreover, all seven genes were found to be differentially expressed in CRC tissues as compared with adjacent normal tissues, indicating their potential role in CRC initiation and progression. This seven-gene signature was further validated as an independent prognostic marker for OS prediction in patients with CRC in other two independent cohorts. In short, we developed a robust seven-gene signature that can predict the OS for CRC patients, providing new insights into identification of CRC patients with high risk of mortality.