Inhibition of STAT6/Anoctamin-1 Activation Suppresses Proliferation and Invasion of Gastric Cancer Cells

Interleukin-4 Promotes Human Metapneumovirus Replication Through the JAK/STAT6 Pathway

Respiratory virus infections are the main causes of pediatric diseases. Human metapneumovirus (hMPV) is an enveloped RNA virus similar to severe acute respiratory syndrome coronavirus type 2, both of which have emerged as important new respiratory viruses. Recent studies have found that interleukin-4 (IL-4) is involved in the replication of a variety of viruses, and its role differs in different viruses. The purpose of this study was to investigate the effect of IL-4 on hMPV and to elucidate its mechanism of action. We found that hMPV infection promoted the expression of IL-4 in human bronchial epithelial cells. The replication of the virus was reduced using small interfering RNA knockdown of IL-4 expression, while the addition of exogenous recombinant human IL-4 to IL-4 knockdown cells restored viral replication ability. These results demonstrate that the expression of IL-4 is closely related to the replication of hMPV; moreover, further experiments revealed that IL-4 promotes the replication of hMPV through a mechanism dependent on the Janus kinase/signal transductor and transcription activator 6 signaling pathway. Therefore, anti-IL-4 strategies may be a promising avenue for the treatment of hMPV infection, representing an important breakthrough for children at risk from hMPV infection.

A pan-cancer analysis of the expression of STAT family genes in tumors and their relationship to the tumor microenvironment

Background

The signal transducer and activator of transcription (STAT) protein family, a group of seven members (STAT1, STAT2, STAT3, STAT4, STAT5A, STAT5B, and STAT6), has been widely used to investigate numerous biological functions including cell proliferation, differentiation, apoptosis, and immune regulation. However, not much is known about the role of the STAT family genes in pan-cancer.

Methods

Tumor Immune Estimation Resource (TIMER), Sangerbox, cBioPortal, GSCALite, Xena Shiny, GeneMANIA, Gene Expression Profiling Interactive Analysis (GEPIA), and Metascape were used to analyze the relationship between STAT gene expression, clinical outcome, gene variation, methylation status, pathway activity, tumor immune infiltration, and microenvironment in different cancer types and screened drugs that could potentially influence STATs.

Results

The Cancer Genome Atlas (TCGA) pan-cancer data showed that most STAT family genes were extensively changed in most tumors compared to the adjacent normal tissues. We also found that STAT gene expression could be used to predict patient survival in various cancers. The STAT gene family formed a network of interaction networks that was associated with several pathways. By mining the of Genomics Drug Sensitivity in Cancer (GDSC) database, we discovered a number of potential drugs that might target STAT regulators. Importantly, the close correlation between STATs and immunocell infiltration suggested the important role of dysregulation of STATs in tumor immune escape. Finally, the relation between STAT gene expression and the tumor microenvironment (TME) indicated that the higher expression of STAT regulators, the higher the degree of tumor stem cells.

Conclusion

Considering these genomic alterations and clinical features of STAT family members across cancer types, it will be possible to change the relationship between STATs and tumorigenesis. It was beneficial to treat cancer by targeting these STAT regulators.

Anoctamin 5 regulates the cell cycle and affects prognosis in gastric cancer

BACKGROUND

Anoctamin 5 (ANO5)/transmembrane protein 16E belongs to the ANO/ transmembrane protein 16 anion channel family. ANOs comprise a family of plasma membrane proteins that mediate ion transport and phospholipid scrambling and regulate other membrane proteins in numerous cell types. Previous studies have elucidated the roles and mechanisms of ANO5 activation in various cancer types. However, it remains unclear whether ANO5 acts as a plasma membrane chloride channel, and its expression and functions in gastric cancer (GC) have not been investigated.

AIM

To examine the role of ANO5 in the regulation of tumor progression and clinicopathological significance of its expression in GC.

METHODS

Knockdown experiments using ANO5 small interfering RNA were conducted in human GC cell lines, and changes in cell proliferation, cell cycle progression, apoptosis, and cellular movement were assessed. The gene expression profiles of GC cells were investigated following ANO5 silencing by microarray analysis. Immunohistochemical staining of ANO5 was performed on 195 primary tumor samples obtained from patients with GC who underwent curative gastrectomy between 2011 and 2013 at our department.

RESULTS

Reverse transcription-quantitative polymerase chain reaction (PCR) and western blotting demonstrated high ANO5 mRNA and protein expression, respectively, in NUGC4 and MKN45 cells. In these cells, ANO5 silencing inhibited cell proliferation and induced apoptosis. In addition, the knockdown of ANO5 inhibited G₁-S phase progression, invasion, and migration. The results of the microarray analysis revealed changes in the expression levels of several cyclin-associated genes, such as CDKN1A, CDK2/4/6, CCNE2, and E2F1, in ANO5-depleted NUGC4 cells. The expression of these genes was verified using reverse transcription-quantitative PCR. Immunohistochemical staining revealed that high ANO5 expression levels were associated with a poor prognosis. Multivariate analysis identified high ANO5 expression as an independent prognostic factor for 5-year survival in patients with GC (P = 0.0457).

CONCLUSION

ANO5 regulates the cell cycle progression by regulating the expression of cyclin-associated genes and affects the prognosis of patients with GC. These results may provide insights into the role of ANO5 as a key mediator in tumor progression and/or promising prognostic biomarker for GC.

Comprehensive analysis of the prognostic and immunotherapeutic implications of STAT family members in human colorectal cancer

Background: Colorectal cancer (CRC) is the third most prevalent cancer worldwide and the second leading cause of cancer mortality. Signal transducer and activator of transcription (STAT) proteins are a group of transcription factors implicated in cell signal transduction and gene transcription in several cancer types. However, the level of expression, genetic alterations, and biological function of different STATs, as well as their prognostic and immunotherapeutic value in CRC remain unclear.

Methods: The mRNA and protein expression levels, genetic alterations, prognostic value, gene–gene and protein–protein interaction networks, and biological function of STATs in CRC were studied using the GEPIA, HPA, cBioPortal, PrognoScan, Kaplan–Meier plotter, GeneMANIA, STRING, and Metascape databases. The expression of STATs in CRC was confirmed using immunohistochemistry (IHC). Finally, the relationship between STAT expression and immune infiltration as well as immunotherapy-associated indicators was also investigated.

Results: The expression levels of STAT2/5A/5B are downregulated in CRC, and the STAT1/3/4/5B expressions were significantly associated with the tumor stage of patients with CRC. The abnormal expression of STAT2/4/5B in patients with CRC is related to the prognosis of patients with CRC. The STATs and their neighboring proteins are primarily associated with lymphocyte activation, cytokine-mediated signaling pathways, positive regulation of immune response, regulation of cytokine production, and growth hormone receptor signaling pathways in cancer. The expression of STATs was significantly associated with immune infiltration and immunotherapy response-associated indicators.

Conclusion: This study may help further understand the molecular mechanism of CRC and provide new prognostic biomarkers and immunotherapy targets in patients with CRC.

Differential Gene Expression and Weighted Correlation Network Dynamics in High-Throughput Datasets of Prostate Cancer

Precision oncology is an absolute need today due to the emergence of treatment resistance and heterogeneity among cancerous profiles. Target-propelled cancer therapy is one of the treasures of precision oncology which has come together with substantial medical accomplishment. Prostate cancer is one of the most common cancers in males, with tremendous biological heterogeneity in molecular and clinical behavior. The spectrum of molecular abnormalities and varying clinical patterns in prostate cancer suggest substantial heterogeneity among different profiles. To identify novel therapeutic targets and precise biomarkers implicated with prostate cancer, we performed a state-of-the-art bioinformatics study, beginning with analyzing high-throughput genomic datasets from The Cancer Genome Atlas (TCGA). Weighted gene co-expression network analysis (WGCNA) suggests a set of five dysregulated hub genes (MAF, STAT6, SOX2, FOXO1, and WNT3A) that played crucial roles in biological pathways associated with prostate cancer progression. We found overexpressed STAT6 and SOX2 and proposed them as candidate biomarkers and potential targets in prostate cancer. Furthermore, the alteration frequencies in STAT6 and SOX2 and their impact on the patients' survival were explored through the cBioPortal platform. The Kaplan-Meier survival analysis suggested that the alterations in the candidate genes were linked to the decreased overall survival of the patients. Altogether, the results signify that STAT6 and SOX2 and their genomic alterations can be explored in therapeutic interventions of prostate cancer for precision oncology, utilizing early diagnosis and target-propelled therapy.

Forecasting Gastric Cancer Diagnosis, Prognosis, and Drug Repurposing with Novel Gene Expression Signatures

Gastric cancer (GC) is a prevalent disease worldwide with high mortality and poor treatment success. Early diagnosis of GC and forecasting of its prognosis with the use of biomarkers are directly relevant to achieve both personalized/precision medicine and innovation in cancer therapeutics. Gene expression signatures offer one of the promising avenues of research in this regard, as well as guiding drug repurposing analyses in cancers. Using publicly accessible gene expression datasets from the Gene Expression Omnibus and The Cancer Genome Atlas (TCGA), we report here original findings on co-expressed gene modules that are differentially expressed between 133 GC samples and 46 normal tissues, and thus hold potential for novel diagnostic candidates for GC. Furthermore, we found two co-expressed gene modules were significantly associated with poor survival outcomes revealed by survival analysis of the RNA-Seq TCGA datasets. We identified STAT6 (signal transducer and activator of transcription 6) as a key regulator of the identified gene modules. Finally, potential therapeutic drugs that may target and reverse the expression of the identified altered gene modules examined for drug repurposing analyses and the unraveled compounds were further investigated in the literature by the text mining method. Accordingly, we found several repurposed drug candidates, including Trichostatin A, Vorinostat, Parthenolide, Panobinostat, Brefeldin A, Belinostat, and Danusertib. Through text mining analysis and literature search validation, Belinostat and Danusertib were suggested as possible novel drug candidates for GC treatment. These findings collectively inform multiple aspects of GC medical management, including its precision diagnosis, forecasting of possible outcomes, and drug repurposing for innovation in GC medicines in the future.

Recent Advances in the Inhibition of the IL-4 Cytokine Pathway for the Treatment of Allergen-Induced Asthma

The IL-4 and IL-13 cytokine pathways play integral roles in stimulating IgE inflammation, with the IL-4 cytokine being a major cytokine in the etiology of thunderstorm asthma, atopic dermatitis, and allergic rhinitis. The increasing prevalence of thunderstorm asthma in the younger population and the lessening efficacy of corticosteroids and other anti-inflammatories has created a need for more effective pharmaceuticals. This review summarizes the IL-4 and IL-13 pathways while highlighting and discussing the current pathway inhibitors aimed at treating thunderstorm asthma and atopic dermatitis, as well as the potential efficacy of peptide therapeutics in this field.

Calcium-Activated Chloride Channel ANO1/TMEM16A: Regulation of Expression and Signaling

Anoctamin-1 (ANO1), also known as TMEM16A, is the most studied member of anoctamin family of calcium-activated chloride channels with diverse cellular functions. ANO1 controls multiple cell functions including cell proliferation, survival, migration, contraction, secretion, and neuronal excitation. This review summarizes the current knowledge of the cellular mechanisms governing the regulation of ANO1 expression and of ANO1-mediated intracellular signaling. This includes the stimuli and mechanisms controlling ANO1 expression, agonists and processes that activate ANO1, and signal transduction mediated by ANO1. The major conclusion is that this field is poorly understood, remains highly controversial, and requires extensive and rigorous further investigation.

The roles of post-translational modifications and coactivators of STAT6 signaling in tumor growth and progression

Signal transducers and activators of transcription 6 (STAT6) are highly expressed in various tumors and associated with tumorigenesis, immunosuppression, proliferation, metastasis and poor prognosis in human cancers. In response to IL-4/13, STAT6 is phosphorylated, dimerizes and triggers transcriptional regulation after recruitment of coactivators to transcriptosome, such as CBP/p300, SRC-1, PARP-14 and PSF. Post-translational modifications, including phosphorylation, ubiquitination, ADP-ribosylation and acetylation, have been explored for molecular mechanisms of STAT6 in tumor development and management. STAT6 has been developed as a specific biomarker for distinguishing and diagnosing tumor phenotypes, although it is observed to be frequently mutated in metastatic tumors. In this article, we focus mainly on the structural characteristics of STAT6 and its role in tumor growth and progression.

LncRNA OIP5-AS1 facilitates gastric cancer cell growth by targeting the miR-422a/ANO1 axis

OPA-interacting protein 5 antisense transcript 1 (OIP5-AS1) plays an important regulatory role in various types of cancers. However, the functional role and regulatory mechanisms of OIP5-AS1 in gastric cancer (GC) remain largely unknown. In this study, we found that the expression of OIP5-AS1 was increased in GC tissues compared with that in adjacent non-cancerous tissues, which was significantly associated with shorter overall survival time of patients. In addition, OIP5-AS1 expression was also increased in GC cell lines including NCI-N87, MKN-45, BGC-823 and SGC-7901, when compared with that in normal gastric epithelial cell line GES-1. Knockdown of OIP5-AS1 markedly suppressed the proliferation and colony formation activities of GC cells, induced G0/G1 arrest and apoptosis of GC cells in vitro, and restrained tumor growth in vivo. Mechanistically, OIP5-AS1 functions as an oncogenic competing endogenous RNA by binding to and sequestering miR-422a to elevate the expression of anoctamin-1. Our study first demonstrated that OIP5-AS1 is a critical and powerful regulator of GC pathogenesis and may represent a novel candidate target for GC therapy.

ANO9 Regulated Cell Cycle in Human Esophageal Squamous Cell Carcinoma

BACKGROUND

Few studies have reported the function and activation mechanism of ANO9 in esophageal squamous cell carcinoma (ESCC). The current study aimed to investigate the role of ANO9 in the regulation of tumor progression.

METHODS

Knockdown experiments with human ESCC cell lines were performed using ANO9 siRNA, and the effects on cell proliferation, the cell cycle, apoptosis, and cellular movement were analyzed. Immunohistochemistry (IHC) analysis was performed on 57 primary tumor samples obtained from ESCC patients.

RESULTS

In an in vitro study, depletion of ANO9 reduced cell proliferation, invasion, and migration in KYSE150 and KYSE 790 cells. In the cell cycle analysis, depletion of ANO9 increased the number of cells in G₀/G₁ arrest. In addition, the knockdown of ANO9 increased apoptosis. The results of the microarray analysis indicated that various centrosome-related genes such as CEP120, CNTRL, and SPAST were up- or downregulated in ANO9-depleted KYSE150 cells. The IHC results showed that high expression of ANO9 was associated with poor prognosis.

CONCLUSIONS

The results of the current study suggest that ANO9 regulates the cell cycle via centrosome-related genes in ESCC.

Role of ion channels in gastrointestinal cancer

In their seminal papers Hanahan and Weinberg described oncogenic processes a normal cell undergoes to be transformed into a cancer cell. The functions of ion channels in the gastrointestinal (GI) tract influence a variety of cellular processes, many of which overlap with these hallmarks of cancer. In this review we focus on the roles of the calcium (Ca2+), sodium (Na+), potassium (K+), chloride (Cl-) and zinc (Zn2+) transporters in GI cancer, with a special emphasis on the roles of the KCNQ1 K+ channel and CFTR Cl- channel in colorectal cancer (CRC). Ca2+ is a ubiquitous second messenger, serving as a signaling molecule for a variety of cellular processes such as control of the cell cycle, apoptosis, and migration. Various members of the TRP superfamily, including TRPM8, TRPM7, TRPM6 and TRPM2, have been implicated in GI cancers, especially through overexpression in pancreatic adenocarcinomas and down-regulation in colon cancer. Voltage-gated sodium channels (VGSCs) are classically associated with the initiation and conduction of action potentials in electrically excitable cells such as neurons and muscle cells. The VGSC NaV1.5 is abundantly expressed in human colorectal CRC cell lines as well as being highly expressed in primary CRC samples. Studies have demonstrated that conductance through NaV1.5 contributes significantly to CRC cell invasiveness and cancer progression. Zn2+ transporters of the ZIP/SLC39A and ZnT/SLC30A families are dysregulated in all major GI organ cancers, in particular, ZIP4 up-regulation in pancreatic cancer (PC). More than 70 K+ channel genes, clustered in four families, are found expressed in the GI tract, where they regulate a range of cellular processes, including gastrin secretion in the stomach and anion secretion and fluid balance in the intestinal tract. Several distinct types of K+ channels are found dysregulated in the GI tract. Notable are hERG1 upregulation in PC, gastric cancer (GC) and CRC, leading to enhanced cancer angiogenesis and invasion, and KCNQ1 down-regulation in CRC, where KCNQ1 expression is associated with enhanced disease-free survival in stage II, III, and IV disease. Cl- channels are critical for a range of cellular and tissue processes in the GI tract, especially fluid balance in the colon. Most notable is CFTR, whose deficiency leads to mucus blockage, microbial dysbiosis and inflammation in the intestinal tract. CFTR is a tumor suppressor in several GI cancers. Cystic fibrosis patients are at a significant risk for CRC and low levels of CFTR expression are associated with poor overall disease-free survival in sporadic CRC. Two other classes of chloride channels that are dysregulated in GI cancers are the chloride intracellular channels (CLIC1, 3 & 4) and the chloride channel accessory proteins (CLCA1,2,4). CLIC1 & 4 are upregulated in PC, GC, gallbladder cancer, and CRC, while the CLCA proteins have been reported to be down-regulated in CRC. In summary, it is clear, from the diverse influences of ion channels, that their aberrant expression and/or activity can contribute to malignant transformation and tumor progression. Further, because ion channels are often localized to the plasma membrane and subject to multiple layers of regulation, they represent promising clinical targets for therapeutic intervention including the repurposing of current drugs.

Synergistic action of dual IGF1/R and MEK inhibition sensitizes childhood acute lymphoblastic leukemia (ALL) cells to cytotoxic agents and involves downregulation of STAT6 and PDAP1

•

Dual insulin-like growth factor 1 receptor (IGF1/R) + mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase (MEK) inhibition synergistically sensitize apoptosis-resistant acute lymphoblastic leukemia (ALL) cells.

•

Dual IGF1/R + MEK inhibition potentiates chemotherapy-induced killing of ALL cells.

•

Signal transducer and activator of transcription 6 (STAT6) and platelet-derived growth factor-associated protein 1 (PDAP1) are downregulated differentially by this synergistic action.

•

STAT6 and PDAP1 are predicted to act in a putative STAT6–ERK–nuclear factor kappa beta (NF-κB) survival network.

•

Targeting this network may be useful for sensitizing ALL to chemotherapy agents.

Heterogeneous upregulation of multiple prosurvival pathways underlies resistance to damage-induced apoptosis in acute lymphoblastic leukemia (ALL) cells despite normal p53 responses. Here, we show that the dual combination of insulin-like growth factor 1 (IGF1)/IGF1 receptor (IGF1/R) and mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK) kinase (MEK) inhibition using AG1024 + U0126 can sensitize apoptosis-resistant ALL cells to ionizing radiation-induced DNA damage irrespective of effect of single pathway inhibition in vitro. This AG1024 + U0126 combination also significantly potentiates the ability of the core chemotherapy compounds vincristine, dexamethasone, and daunorubicin to kill ALL cells in vitro. Evidence of the synergistic action of AG1024 + U0126 in samples with variable basal levels of phosphorylated IGF1/Rβ and ERK1/2 suggested additional targets of this drug combination. Consistent with this, gene expression profiling identified 32 “synergy genes” differentially targeted by IGF1/R + MEK inhibition and, among these, Signal transducer and activator of transcription 6 (STAT6) and platelet-derived growth factor-associated protein 1 (PDAP1) were the most differentially downregulated cluster. Pearson correlation analysesrevealed that STAT6 and PDAP1 display significant expression codependency and a common expression pattern linked with other key “synergy” genes, supporting their predicted role in an STAT6–ERK–nuclear factor kappa beta (NF-κB) network. Knockdown studies revealed that loss of STAT6, but not PDAP1, impinges on the cell cycle, causing reduced numbers of viable cells. In combination with daunorubicin, STAT6 loss has an additive effect on cell killing, whereas PDAP1 loss is synergistic, indicating an important role of PDAP1 in the cellular response to this anthracycline. Inhibition of STAT6 or PDAP1 may therefore represent a potential novel therapeutic strategy for resistant ALL by enhancing sensitivity to chemotherapy.