ITGA5 Expression Research Articles

ITGA5 Promotes Tumor Progression through the Activation of the FAK/AKT Signaling Pathway in Human Gastric Cancer

Background ITGA5 is an adhesion molecule that integrates the intracellular structures with the extracellular matrix to perform biological functions. However, ITGA5 is highly expressed in a variety of tumors and is involved in tumor progression by promoting cell proliferation and metastasis. Nevertheless, little research has been performed on its function in gastric cancer. Therefore, the aim of this study was to investigate the role of ITGA5 in gastric cancer, focusing on the mechanism regulating the proliferation, invasion and migration. Methods The expression of ITGA5 in gastric cancer tissues was assessed by the use of molecular bioinformatics databases and high-throughput sequencing of gastric cancer tissues from patients. Western blot, qPCR, and immunohistochemistry were performed to detect the expression of ITGA5 in samples from gastric cancer patients and gastric cancer cell lines. Furthermore, the ITGA5 gene was silenced and overexpressed in gastric cancer cells, and the effect on proliferation, invasion, migration, and tumorigenic ability was assessed. Results ITGA5 mRNA and protein expression were upregulated in gastric cancer cell lines and tissues from patients, and its expression was closely associated with tumor size, lymph node metastasis, and TNM stage. In vitro and in vivo experiments showed that ITGA5 silencing resulted in the inhibition of proliferation, invasion, migration, and graft growth of gastric cancer cells; conversely, the overexpression resulted in the promotion of these cell functions. Our results finally showed that the effect of ITGA5 on proliferation, invasion, and migration of gastric cancer cells was performed through the activation of the FAK/AKT pathway. Conclusions ITGA5 promotes proliferation, invasion, and migration of gastric cancer cells through the activation of FAK/AKT signaling pathway, suggesting that ITGA5 may be potentially considered as a new target in gastric cancer therapy.

Candesartan Reduces Neuronal Apoptosis Caused by Ischemic Stroke via Regulating the FFAR1/ITGA4 Pathway.

Ischemic stroke (IS) is a general term for necrosis of brain tissue caused by stenosis, occlusion of arteries supplying blood to the brain (carotid artery and vertebral artery), and insufficient blood supply to the brain. Cerebral ischemia is the main kind of IS causing cell damage. However, the underlying mechanism still needs to be clarified further. In this study, it was demonstrated that FFAR1 was a hub gene in IS. The expression of FFAR1 was increased in PC12 cells with OGD/R treatment. FFAR1 deficiency inhibited cell viability and induced cell apoptosis, which was reversed by FFAR1 overexpression. Moreover, candesartan, as a compound targeting FFAR1, facilitated cell viability and reduced cell apoptosis. The expression of ITGA4 was also high in OGD/R-PC12 cells as FFAR1. Furthermore, FFAR1 deficiency retarded the increasing of cell viability and inhibition of cell apoptosis by downregulation of Bax and Cleaved Caspase-3 in OGD/R-PC12 cells with candesartan treatment. In conclusion, candesartan may regulate neuronal apoptosis through FFAR1/ITGA4 axis.

Gene Expression Patterns of Osteopontin Isoforms and Integrins in Malignant Melanoma.

Osteopontin (OPN) is a multifunctional glycoprotein that physiologically interacts with different types of integrins. It is considered to be a possible prognostic biomarker in certain tumor types; however, various splicing isoforms exist, which have not been investigated in melanoma. We aimed to define the relative expression pattern of five OPN isoforms and clarify the prognostic significance of the splice variants in melanoma. We also aimed to investigate the expression pattern of eight integrins in the same tumors. Gene expression analyses revealed that the relative expression of OPNa, OPNb, and OPNc is significantly higher in metastatic tumors compared to primary lesions (p < 0.01), whereas the expression of OPN4 and OPN5 was low in both. The more aggressive nodular melanomas had higher expression levels compared to the superficial spreading subtype (p ≤ 0.05). The relative expression of the eight tested integrins was low, with only the expression of ITGB3 being detectable in nodular melanoma (Medianlog2 = 1.274). A positive correlation was found between Breslow thickness and the expression of OPNc variant, whereby thicker tumors (>4 mm) had significantly higher expression (p ≤ 0.05). The Breslow thickness was negatively correlated with the expression of OPN4, and similarly with ITGA2. OPNc also exhibited significant positive correlation with the presence of metastasis. Our data show that high expression of OPNa, OPNb, and especially OPNc and low expression of OPN4 and ITGA2 are associated with an advanced stage of tumor progression and poor prognosis in melanoma.

ITGA2 overexpression inhibits DNA repair and confers sensitivity to radiotherapies in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is a dismal disease with a 5-year survival rate of less than 10%, despite the recent advances in chemoradiotherapy. The sensitivity of the PDAC patients to chemoradiotherapy varies widely, especially to radiotherapy, suggesting the need for more elucidation of the underlying mechanisms. In this study, a novel function of the nuclear ITGA2, the alpha subunit of transmembrane collagen receptor integrin alpha-2/beta-1, regulating the DNA damage response (DDR), was identified. First, analyzing The Cancer Genome Atlas (TCGA) PDAC data set indicated that the expression status of ITGA2 was negatively correlated with the genome stability parameters. The study further demonstrated that ITGA2 specially inhibited the activity of the non-homologous end joining (NHEJ) pathway and conferred the sensitivity to radiotherapy in PDAC by restraining the recruitment of DNA-dependent protein kinase catalytic subunit (DNA-PKcs) to Ku70/80 heterodimer during DDR. Considering the overexpression of ITGA2 and its associated with the poor prognosis of PDAC patients, this study suggested that the ITGA2 expression status could be used as an indicator for radiotherapy and DNA damage reagents, and the radiotherapy in combination with the overexpression of ITGA2 might be a viable treatment strategy for the PDAC patients.

Association between the baseline gene expression profile in periapical granuloma and periapical wound healing after surgical endodontic treatment

In this study, we have investigated the association between the baseline gene expression profile in periapical granuloma and periapical wound healing after surgical endodontic treatment. Twenty-seven patients aged between 15 and 57 years underwent periapical surgery. The retrieved periapical tissue sample was used for mRNA expression analysis of COL1A1, VTN, ITGA5, IL-4, TNF, ANGPT, VEGFA, and CTGF. All patients were recalled after 6 and 12 months for periapical healing evaluation. Healing was then correlated with baseline gene expression. Healing was observed in 15 patients at the end of 6 months, which increased to 21 patients after 12 months. Six patients showed no healing even after 12 months. Analysis of baseline expression levels of the tested genes with healing status showed the mean relative expression of VTN, VEGFA, ANGPT, TNF, and CTGF to be significantly different (p < 0.05) between the healing group (6 and 12 months) (72.99%) and the non-healing (94.42%) group. Periapical Index scores 3–5 exhibited a positive correlation with ITGA-5 expression. Overexpression of ANGPT and a strong positive correlation between ITGA5 and PAI scores in the non-healing group of patients may suggest these genes to be a potential prognostic biomarker for periapical wound non-healing after surgical endodontic treatment.

Alpha2beta1 Integrin Polymorphism in Diffuse Astrocytoma Patients.

Integrins are heterodimeric transmembrane glycoproteins resulting from the non-covalent association of an α and β chain. The major integrin receptor for collagen/laminin, α2β1 is expressed on a wide variety of cell types and plays an essential role in the adhesion of normal and tumor cells to the extracellular matrix. Integrin-triggered signaling pathways promote the invasion and survival of glioma cells by modifying the brain microenvironment. In this study, we investigated the association of a specific genetic polymorphism of integrin α2β1 with the incidence of diffusely infiltrating astrocytoma and the progression of these tumors. Single-nucleotide polymorphism in intron 7 of the integrin ITGA2 gene was examined in 158 patients and 162 controls using polymerase chain reaction and restriction enzyme analysis. The ITGA2 genotype +/+ (with a BglII restriction site in both alleles) exhibited higher frequency in grade II astrocytoma compared to control (P = 0.02) whereas the genotype -/- (lacking the BglII site) correlated with the poorest survival rate (P = 0.04). In addition, in silico analyses of ITGA2 expression from low-grade gliomas (LGG, n = 515) and glioblastomas (GBM, n = 159) indicated that the higher expression of ITGA2 in LGG was associated with poor overall survival (P < 0.0001). However, the distribution of integrin ITGA2 BglII genotypes (+/+, +/-, -/-) was not significantly different between astrocytoma subgroups III and IV (P = 0.65, 0.24 and 0.33; 0.29, 0.48, 0.25, respectively) compared to control. These results suggest a narrow association between the presence of this SNP and indicate that further studies with larger samples are warranted to analyze the relation between tumor grade and overall survival, highlighting the importance of determining these polymorphisms for prognosis of astrocytomas.

Poor Prognosis of Oral Squamous Cell Carcinoma Correlates With ITGA6

ObjectivesOral cancer is the ninth most common cancer worldwide and a leading cause of cancer-related death. Oral squamous cell carcinoma (OSCC) accounts for 90% of all oral cancers. Autophagy is a conserved essential catabolic process related to OSCC. The aim of this study was to elucidate diagnostic and prognostic autophagy-related biomarkers in OSCC. MethodsThe OSCC gene expression data set was obtained from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) between the OSCC samples and adjacent healthy tissues were identified by R software. The Human Autophagy Database was screened, which revealed 222 autophagy-related genes. The autophagy-related DEGs were identified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were applied. Protein–protein interaction network analysis was performed in the STRING database. cytoHubba in the Cytoscape software was applied to determine the top 10 hub genes. The data set of patients with OSCC from The Cancer Genome Atlas (TCGA) was used to evaluate the prognostic value of the 10 hub genes. The association between prognosis-related hub genes and immune infiltrates was explored. ResultsTwenty-seven autophagy-related DEGs were identified. The top 10 hub genes were CCL2, CDKN2A, CTSB, CTSD, CXCR4, ITGA6, MAP1LC3A, MAPK3, PARP1, and RAB11A. ITGA6 was identified as the most efficient biomarker. Receiver operating characteristic curve analysis indicated that ITGA6 had the highest diagnostic accuracy for OSCC (area under the curve = 0.925). ITGA6 expression was significantly related to immune infiltrates. ConclusionsThe autophagy-related gene ITGA6 might be an efficient diagnostic and prognostic biomarker in OSCC.

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.

Oncogenic GBX2 promotes the malignant behaviors of bladder cancer cells by binding to the ITGA5 promoter and activating its transcription.

In bladder cancer patients, metastasis after surgical resection and serious adverse reactions brought by cisplatin-based systemic chemotherapy make it urgent to explore novel therapeutic methods for improving the clinical outcomes of patients with unsuccessful first-line chemotherapy and disease progression. In this study, GBX2 has been recognized as a differentially expressed transcriptional factor between bladder cases with response to treatment and progressive disease based on online expression profile analysis. Higher GBX2 expression was correlated with poorer OS, DSS, and PFS in bladder cancer patients. GBX2 co-expressed genes were enriched in ECM regulation. ITGA5 was positively correlated with GBX2. GBX2 and ITGA5 were notably elevated in bladder cancer cells. GBX2 and ITGA5 similarly affected bladder cancer cell phenotypes via facilitating cell viability, migration, and invasion. By binding to the promoter region of ITGA5, GBX2 activated ITGA5 transcription, upregulating ITGA5 expression. In bladder cancer cells co-transfected with sh-GBX2 and ITGA5 oe, the inhibitory effects of GBX2 knockdown on bladder cancer cell malignant behaviors were partially eliminated by ITGA5 overexpression. In conclusion, GBX2 and ITGA5 serve as oncogenic factors, promoting the viability, migration, and invasion of bladder cancer cells. GBX2 exerts its functions by targeting the ITGA5 promoter region to activate ITGA5 transcription.

The miR-410-5p /ITGA6 axis participates in the pathogenesis of recurrent abortion by regulating the biological function of trophoblast

The purpose of this study was to determine the regulation of the miR-410-5p /ITGA6 axis on the biological functions of trophoblast cells and the mechanism involved in recurrent spontaneous abortion（RSA）. We used qRT-PCR and Western blotting to quantify the expression levels of Mir-410-5p and ITGA6 in placenta of RSA and normal, and found that compared with normal placenta, the placenta of RSA patients showed higher miR-410-5p and lower ITGA6 expression. Dual luciferase reporter gene assay confirmed the binding of miR-410-5p to ITGA6. The expression of miR-410-5p and ITGA6, and proliferation, apoptosis, invasion and migration of trophoblast cells and the effect on the polarization of M2 macrophages were detected in the trophoblast derived cell lines HTR8/Svneo transfected with miR-410-5p mimic, sh-miR-410-5p and si-ITGA6 respectively. Meanwhile, the molecular mechanism of ITGA6 regulation on trophoblast cells was explored. Transfection with miR-410-5p mimic or si-ITGA6 attenuated the proliferation, migration and invasion and induced apoptosis of HTR-8/SVneo cells. Transfection of sh-miR-410-5p promoted proliferation, migration and invasion, and weakened apoptosis of HTR-8/SVneo cells. In addition, overexpression of miR-410-5p in trophoblast cells inhibited the polarization of M2 macrophages, while knockdown of miR-410-5p was beneficial to recruitment of trophoblast cell and promoted the polarization of M2 macrophages. ITGA6 may affect the biological functions of trophoblast cells by regulating PI3K/AKT and MAPK signaling pathways. In conclusion, miR-410-5p mediates trophoblast cell proliferation, apoptosis, invasion and migration through regulating ITGA6 expression.

EP3 enhances adhesion and cytotoxicity of NK cells toward hepatic stellate cells in a murine liver fibrosis model

Natural killer (NK) cells exhibit antifibrotic properties in liver fibrosis (LF) by suppressing activated hepatic stellate cell (HSC) populations. Prostaglandin E2 (PGE2) plays a dual role in innate and adaptive immunity. Here, we found that E-prostanoid 3 receptor (EP3) was markedly downregulated in NK cells from liver fibrosis mice and patients with liver cirrhosis. NK cell-specific deletion of EP3 aggravated hepatic fibrogenesis in mouse models of LF. Loss of EP3 selectively reduced the cytotoxicity of the CD27+CD11b+ double positive (DP) NK subset against activated HSCs. Mechanistically, deletion of EP3 impaired the adhesion and cytotoxicity of DP NK cells toward HSCs through modulation of Itga4-VCAM1 binding. EP3 upregulated Itga4 expression in NK cells through promoting Spic nuclear translocation via PKC-mediated phosphorylation of Spic at T191. Activation of EP3 by sulprostone alleviated CCL4-induced liver fibrosis in mice. Thus, EP3 is required for adhesion and cytotoxicity of NK cells toward HSCs and may serve as a therapeutic target for the management of LF.

Free or fixed state of nHAP differentially regulates hBMSC morphology and osteogenesis through the valve role of ITGA7.

Nano-hydroxyapatite (nHAP) has been widely used in bone repair as an osteo-inductive and naturally-occurring material. However, the optimal applied form of nHAP and the underlying mechanisms involved remain unclear. Herein, to investigate into these, a range of corresponding models were designed, including three applied forms of nHAP (Free, Coating and 3D) that belong to two states (Free or fixed). The results indicate that when fixed nHAP was applied in the 3D form, optimal osteogenesis was induced in human bone marrow stem cells (hBMSCs) with increased bone volume via integrin α7 (ITGA7)-mediated upregulation of the PI3K-AKT signaling pathway, while contrary results were observed with free nHAP. Ectopic osteogenesis experiments in mice subcutaneous transplantation model further confirmed the different tendencies of ITGA7 expression and osteogenesis of hBMSCs in free and fixed states of nHAP. Our results revealed that the two states of nHAP play a different regulatory role in cell morphology and osteogenesis through the valve role of ITGA7, providing cues for better application of nanoparticles and a potential new molecular target in bone tissue engineering.

Aminoflavone upregulates putative tumor suppressor miR-125b-2-3p to inhibit luminal A breast cancer stem cell-like properties.

Metastatic breast cancer is incurable and often due to breast cancer stem cell (CSC)-mediated self-renewal. We previously determined that the aryl hydrocarbon receptor (AhR) agonist aminoflavone (AF) inhibits the expression of the CSC biomarker α6-integrin (ITGA6) to disrupt the formation of luminal (hormone receptor-positive) mammospheres (3D breast cancer spheroids). In this study, we performed miRNA-sequencing analysis of luminal A MCF-7 mammospheres treated with AF to gain further insight into the mechanism of AF-mediated anti-cancer and anti-breast CSC activity. AF significantly induced the expression of >70 microRNAs (miRNAs) including miR125b-2–3p, a predicted stemness gene regulator. AF-mediated miR125b-2–3p induction was validated in MCF-7 mammospheres and cells. miR125b-2–3p levels were low in breast cancer tissues irrespective of subtype compared to normal breast tissues. While miR125b-2–3p levels were low in MCF-7 cells, they were much lower in AHR100 cells (MCF-7 cells made unresponsive to AhR agonists). The miR125b-2–3p mimic decreased, while the antagomiR125b-2–3p increased the expression of stemness genes ITGA6 and SOX2 in MCF-7 cells. In MCF-7 mammospheres, the miR125b-2–3p mimic decreased only ITGA6 expression although the antagomiR125b-2–3p increased ITGA6, SOX2 and MYC expression. AntagomiR125b-2–3p reversed AF-mediated suppression of ITGA6. The miR125b-2–3p mimic decreased proliferation, migration, and mammosphere formation while the antagomiR125b-2–3p increased proliferation and mammosphere formation in MCF-7 cells. The miR125b-2–3p mimic also inhibited proliferation, mammosphere formation, and migration in AHR100 cells. AF induced AhR- and miR125b2-3p-dependent anti-proliferation, anti-migration, and mammosphere disruption in MCF-7 cells. Our findings suggest that miR125b-2–3p is a tumor suppressor and AF upregulates miR125b-2–3p to disrupt mammospheres via mechanisms that rely at least partially on AhR in luminal A breast cancer cells.

MiR-4484 regulates the expression of integrin α 6 in gastric cancer tissues and its significance

Objective: To investigate the relationship between the expression of integrin α 6 (ITGA6), miR-4484 and the pathologic stage of gastric cancer. Methods: Gastric cancer tissues and normal gastric mucosa tissues adjacent to cancer (>5 cm from tumor margin) of 30 patients with primary gastric cancer who underwent direct surgical resection without adjuvant therapy from June to September 2017 in West China Hospital of Sichuan University were selected. Real-time quantitative polymerase chain reaction (PCR) was used to detect the expression levels of miR-4484 and ITGA6, western blot was used to detect the expression level of ITGA6 protein, dual luciferase reporter gene was used to verify the relationship between ITGA6 and miR-4484. Spearman's correlation analysis was used to determine the relationship between miR-4484 and ITGA6 expression levels in gastric cancer tissues. Results: The expression level of ITGΑ6 in gastric cancer (32.30±13.47) was higher than that in matched normal gastric tissues (24.55±10.25, P=0.015), the area under the receiver operating characteristic (ROC) curve was 0.660 and the diagnostic sensitivity and specificity were 43.3% and 96.7%, respectively. The expression level of miR-4484 in gastric cancer (4.11±2.87) was lower than that of matched normal gastric tissues (5.75±2.80, P=0.029), the area under the ROC curve was 0.690 and the diagnostic sensitivity and specificity were 30.0% and 86.7%, respectively. The expression level of miR-4484 was negatively correlated with ITGA6 in gastric cancer tissues (r=-0.621, P<0.001). The expression level of ITGA6 protein in gastric cancer tissues (0.65±0.19) was higher than that in normal adjacent tissues (0.26±0.12, P<0.001). Compared with ITGA6 3'UTR wild-type+ miR-NC group, ITGA6 3'UTR wild-type+ miRNA mimics group had lower luciferase activity (50.69±5.10, 34.00±1.19, P<0.001), while the luciferase activity of ITGA6 3'UTR wild-type+ ASO miR-4484 group was higher than that of ITGA6 3'UTR wild-type+ miR-NC group (82.44±6.37, 50.69±5.10, P<0.001), indicated that ITGA6 was the direct target gene of miR-4484. The expression levels of miR-4484 in T1, T2, T3 and T4 (4a and 4b) gastric cancer tissues were 9.98±2.24, 5.28±2.03, 2.92±2.04 and 4.11±2.87, respectively, with statistical significance (P<0.001). The expression levels of ITGA6 in N0, N1, N2 and N3 gastric cancer tissues were 29.55±8.32, 21.71±3.75, 24.60±8.79 and 40.69±15.83, respectively, with statistical significance (P=0.022). The expression levels of miR-4484 in N0, N1, N2 and N3 gastric cancer tissues were 5.01±3.52, 5.48±2.76, 5.88±1.83 and 2.30±1.56, respectively, with statistical significance (P=0.032). The expression levels of ITGA6 in M0 and M1 gastric cancer tissues were 26.28±7.66 and 52.08±8.12, respectively, with statistical significance (P<0.001). The expression levels of miR-4484 in M0 and M1 gastric cancer tissues were 4.95±2.74 and 1.34±0.80, respectively, with statistical significance (P<0.001). Conclusions: ITGA6 is upregulated in gastric cancer tissues, while miR-4484 is downregulated in the gastric cancer group, and its expression level is related to the clinicopathological features of gastric cancer. ITGA6 is the direct target gene of miR-4484, implicates that miR-4484 may inhibit the invasion and metastasis of gastric cancer by regulating the expression of ITGA6. Both miR-4484 and ITGA6 may be the new prognostic markers and potential therapeutic targets of gastric cancer.

ITGA5 Is a Novel Oncogenic Biomarker and Correlates With Tumor Immune Microenvironment in Gliomas.

Gliomas are the most aggressive primary intracranial malignancies with poor overall survival. ITGA5 is one member of the integrin adhesion molecule family and is implicated in cancer metastasis and oncogenesis. However, few studies have explored the association between tumor immune microenvironment and ITGA5 expression level in gliomas. Firstly, we analyzed 3,047 glioma patient samples collected from the TCGA, the CGGA, and the GEO databases, proving that high ITGA5 expression positively related to aggressive clinicopathological features and poor survival in glioma patients. Then, based on the ITGA5 level, immunological characteristics and genomic alteration were explored through multiple algorithms. We observed that ITGA5 was involved in pivotal oncological pathways, immune-related processes, and distinct typical genomic alterations in gliomas. Notably, ITGA5 was found to engage in remolding glioma immune infiltration and immune microenvironment, manifested by higher immune cell infiltration when ITGA5 is highly expressed. We also demonstrated a strong correlation between ITGA5 and immune checkpoint molecules that may be beneficial from immune checkpoint blockade strategies. In addition, ITGA5 was found to be a robust and sensitive indicator for plenty of chemotherapy drugs through drug sensitivity prediction. Altogether, our comprehensive analyses deciphered the prognostic, immunological, and therapeutic value of ITGA5 in glioma, thus improving individual and precise therapy for combating gliomas.

The relationship among integrin alpha 7, CD133 and Nestin as well as their correlation with clinicopathological features and prognosis in astrocytoma patients

ObjectiveIntegrin alpha 7 (ITGA7), a potential glioma stem cell marker, regulates several other stem cell markers including CD133 and Nestin in several cancers, meanwhile its high expression is related to poor prognosis in multiple solid tumor patients. However, few studies report correlation of ITGA7 with prognosis in astrocytoma patients. Hence, this study aimed to determine the astrocytoma-tissue ITGA7, CD133 and Nestin expressions to explore their relationship and clinical value for astrocytoma management. MethodsTotally, 124 patients with primary astrocytoma were included. Their tumor tissue ITGA7, CD133 and Nestin expressions were determined by immunohistochemical (IHC) assay and scored by intensity and density ranging from 0 to 12 points. Besides, their clinical features (such as world health organization (WHO) grade, isocitrate dehydrogenase (IDH) mutation, and adjuvant therapy etc.) were collected, also their overall survival (OS) were analyzed by follow-up data. ResultsThe mean IHC scores for ITGA7, CD133 and Nestin were 4.9 ± 2.5, 2.1 ± 2.6 and 5.8 ± 2.6, respectively. Moreover, ITGA7 high expression correlated with absence of IDH mutation (P = 0.004), advanced WHO grade (P = 0.001) and shorter OS (P = 0.005). Besides, ITGA7 positively correlated with CD133 (P = 0.001) and Nestin (P = 0.001) expressions. Regarding CD133 and Nestin, their high expression also correlated with increased WHO grade and shorter OS. Furthermore, multivariant Cox’s regression analysis displayed that only CD133 high expression (P = 0.021) could independently predict reduced OS, while ITGA7 or Nestin high expression could not independently predict that. ConclusionITGA7, CD133, and Nestin are intercorrelated, also their high expressions associate with deteriorating disease conditions and poor prognosis in astrocytoma patients.

Overexpressed integrin alpha 2 inhibits the activation of the transforming growth factor \u03b2 pathway in pancreatic cancer via the TFCP2-SMAD2 axis

BackgroundIntegrin alpha 2 (ITGA2) has been recently reported to be an oncogene and to play crucial roles in tumor cell proliferation, invasion, metastasis, and angiogenesis. Our previous study showed that ITGA2 was overexpressed in pancreatic cancer and promoted its progression. However, the mechanism of ITGA2 overexpression and other mechanisms for promoting the progression of pancreatic cancer are still unclear.MethodsThe GEPIA database was used to confirm the expression of ITGA2 in pancreatic cancer. To verify the influence of ITGA2 and TGF-β on the morphological changes of pancreatic cancer and tumor cell progression, we conduct CCK8 test, plate cloning, flow cytometry experiments and animal experiments. Then we conduct Western blot, RT-qPCR to explore the relationship between ITGA2 and TGF-β, and then find the key molecules which can regulate them by immunoprecipitation, Western blot, RT-qPCR, CHIP, nuclear and cytoplasmic separation test.ResultsThe results of the present study show that the abnormal activation of KRAS induced the overexpression of ITGA2 in pancreatic cancer. Moreover, ITGA2 expression significantly suppressed the activation of the TGF-β pathway. ITGA2 silencing enhanced the anti-pancreatic cancer proliferation and tumor growth effects of TGF-β. Mechanistically, ITGA2 expression suppressed the activation of the TGF-β pathway by inhibiting the SMAD2 expression transcriptionally. In addition, it interacted with and inhibited the nuclear translocation of TFCP2, which induced the SMAD2 expression as a transcription factor. Furthermore, TFCP2 also induced ITGA2 expression as a transcription factor, and the TFCP2 feedback regulated the ITGA2-TFCP2-SMAD2 pathway.ConclusionsTaken together, these results indicated that ITGA2 expression could inhibit the activation of the TGF-β signaling pathway in pancreatic cancer via the TFCP2-SMAD2 axis. Therefore, ITGA2, by effectively enhancing the anti-cancer effects of TGF- β, might be a potential clinical therapeutic target for pancreatic cancer.

Association of ITGA 11 and ITGAV upregulation with outcomes in gastric cancer.

332 Background: Gastric cancer (GC) is a common cancer worldwide. The integrin α (ITGA) family members play essential roles in various cancers and variants of ITGA are involved in metastatic process in gastric cancer. Thus, this study was conducted to explore the roles of ITGA family members in stomach adenocarcinoma (STAD). Methods: RNA-sequencing FPKM data and corresponding clinical information of 375 STAD tumor tissues and 32 normal tissues were retrieved from The Cancer Genome Atlas (TCGA). The ‘limma’ package was used to compare the expression differences between the normal and cancer tissues using Wilcoxon rank-sum test. Analysis of overall survival (OS) was conducted by Kaplan–Meier (K–M) method via ‘survminer’ package. Univariate Cox hazard regression analysis was applied to seven clinicopathological variables from T stage, N stage, M stage, pathologic stage, histologic grade, gender, age, and expression level of selected ITGA family members, by using ‘survival’ package. Furthermore, a nomogram was also visualized by the R ‘rms’ package and ‘survival’ package to predict the 1-, 3-, and 5-year OS and individual predictors. Results: The expression of ITGA2, ITGA3, ITGA4, ITGA5, ITGA6, ITGA11, and ITGAV were upregulated in STAD tissues compared with normal tissues (P&lt;0.05), whereas ITGA7, ITGA8, and ITGA9 were downregulated in tumor tissues (P&lt;0.05). In addition, no statistically significant difference was found for TGA1 and ITGA10 between tumor and normal tissues ((P&gt;0.05). Further survival analysis found that higher expression of ITGA 11 (HR=1.46, 95%CI 1.05-2.03, P&lt;0.026) and ITGAV (HR=1.92, 95%CI 1.37-2.70, P&lt;0.001) were associate with worse OS. Univariate Cox hazard regression analysis showed that T3, T4, N1, N3, M1, pathologic stage III and IV, age&gt;65, and high expression level of ITGA11 and ITGAV were associated with worse OS (all P &lt; 0.05). The nomogram based on six clinicopathological variables (T stage, N stage, M stage, pathologic stage, age, and expression levels of ITGA11 and ITGAV) and 1-, 3-, 5-year OS probabilities were developed. The concordance index (C-index) of the nomograms was 0.673(0.647-0.700), indicating that the potential predicting role and sufficient discrimination ability of the nomogram as C-index was more than 0.5. The calibration curves of 1-, 3-, and 5-year indicated the consistency of our results and the predictive values, indicating satisfactory performance for this nomogram. However, 1-, 3-, 5-year AUCs of ITGA11- and ITGAV-based nomogram were 0.687, 0.691, and 0.687, showing a relatively acceptable accuracy as they were great than 0.5. Conclusions: ITGA2, ITGA3, ITGA4, ITGA5, ITGA6, ITGA11, and ITGAV are upregulated, while ITGA7, ITGA8, and ITGA9 are down regulated in STAD tumor samples. High expression levels of ITGA11 and ITGAV are associated with worse OS. The ITGA11- and ITGAV-based monogram developed by this study might be useful in predicting the OS outcome for STAD patients.

Evaluation of ITGA3 as a Biomarker of Progression and Recurrence in Papillary Thyroid Carcinoma.

ObjectiveTo investigate the expression of ITGA3 and its association with clinical outcomes in papillary thyroid carcinoma (PTC).MethodsThe expression level, association with clinicopathologic characteristics, co-expressed genes, signaling pathways of ITGA3 in thyroid cancer were comprehensively analyzed using bioinformatics analysis through multiple public gene databases. PTC specimens and cell lines were used to verify the results of bioinformatics analysis.ResultsData mining based on the Oncomine database revealed that ITGA3 expression in classical PTC and tall cell variant PTC was much higher than that in normal thyroid tissue except the follicular variant PTC. Analysis based on The Cancer Genome Atlas (TCGA) database showed that the expression of ITGA3 varies greatly in pathological stages, pathological types, tumor invasion stages, and lymph node metastasis stages of thyroid carcinoma. High expression level of ITGA3 was correlated with tumor regional invasion and lymph node metastasis. Multivariate analysis using logistic regression model showed that high expression of ITGA3 was a risk factor that associated with PTC recurrence and lymph node metastasis. Survival analysis showed that patients with high expression of ITGA3 in PTC had a poorer relapse-free survival (RFS) than patients with low expression of ITGA3 (P < 0.05). Immunohistochemistry experiments showed that the expression of ITGA3 in recurrent thyroid cancer tissues was stronger than that in no-recurrent thyroid cancer tissues (P < 0.05). Knockdown of ITGA3 by sh-RNA in PTC cell lines suppresses cell viability and invasive and migrating capacity.ConclusionITGA3 is overexpressed in PTC, especially in those with higher tumor invasion grades and lymph node metastasis, and was associated with recurrence and poor RFS of PTC. High expression of ITGA3 may have the potential role of predicting PTC recurrence and lymph node metastasis.

A novel long non-coding RNA regulates the integrin, ITGA2 in breast cancer.

ITGA2 encodes the integrin, α2 which mediates metastatic progression, and is a predictor of poor prognosis and chemoresistance in breast cancer. Decreased ITGA2 promoter methylation is implicated as a driver of increased gene expression in aggressive prostate and pancreatic tumours, however the contribution of altered methylation to ITGA2 expression changes in breast tumours has not been examined. ITGA2 gene methylation and gene expression was examined in publicly available breast cancer datasets, and ITGA2 promoter methylation was mapped by targeted bisulphite sequencing analysis in breast tumour cell lines. The expression of a putative regulatory long noncoding RNA (lncRNA) was examined by qPCR and its' functionality was investigated using gene knockdown (antisense oligonucleotides) and over expression in breast cancer cell lines. In breast tumours and breast cancer cell lines the ITGA2 promoter is largely unmethylated, with gene expression variable in tumour subtypes, irrespective of promoter methylation. A novel lncRNA (AC025180.1;ENSG00000249899), named herein I2ALR, was identified at the ITGA2 gene locus, and was variably expressed in breast tumours and breast cancer cell subtypes. I2LAR knockdown resulted in upregulation of ITGA2 gene expression, whilst over-expression of I2ALR resulted in downregulation of ITGA2 mRNA. Further, examination of two downstream targets of ITGA2 associated with breast tumor stemness and metastasis (CCND1 and ACLY), revealed concomitant gene expression changes in response to I2ALR modulation. I2ALR represents a novel regulatory molecule targeting ITGA2 expression in breast tumours; a finding of significant and topical interest to the development of therapeutics targeting this integrin.