Inhibition of the JAK2/STAT3 pathway reduces gastric cancer growth in vitro and in vivo

Role of the JAK2/STAT3 pathway on infection of Francisella novicida

Francisella tularensis is a causative agent of the zoonotic disease tularemia, and is highly pathogenic to humans. The pathogenicity of this bacterium is largely attributed to intracellular growth in host cells. Although several bacterial factors important for the intracellular growth have been elucidated, including the type VI secretion system, the host factors involved in the intracellular growth of F. tularensis are largely unknown. To identify the host factors important for F. tularensis infection, 368 compounds were screened for the negative regulation of F. tularensis subsp. novicida (F. novicida) infection. Consequently, 56 inhibitors were isolated that decreased F. novicida infection. Among those inhibitors, we focused on cucurbitacin I, an inhibitor of the JAK2/ STAT3 pathway. Cucurbitacin I and another JAK2/STAT3 inhibitor, Stattic, decreased the intracellular bacterial number of F. novicida. However, these inhibitors failed to affect the cell attachment or the intrasaccular proliferation of F. novicida. In addition, treatment with these inhibitors destabilized actin filaments. These results suggest that the JAK2/STAT3 pathway plays an important role in internalization of F. novicida into host cells through mechanisms involving actin dynamics, such as phagocytosis.

Schisandrin inhibits VSMCs proliferation and migration by arresting cell cycle and targeting JAK2 to regulating the JAK2/STAT3 pathway

Abnormal proliferation, migration, and foam cell formation of Vascular smooth muscle cells (VSMCs) each play a role in the development of atherosclerosis (AS). Schisandrin (Sch) is the active lignan ingredient with broad-spectrum pharmacological effects. However, the role of Sch in the AS process is not clear. Therefore, this study was proposed to explore the therapeutic effect and potential mechanism of Sch on VSMCs. Ox-LDL was selected to create an atherosclerosis injury environment for VSMCs and macrophages. The MTT assay, Oil red O staining, wound healing, transwell experiments and ELISA were used to investigate the phenotype effects of Sch. Network pharmacology, molecular docking, flow cytometry, and western blot were used to investigate the underlying mechanisms of Sch on AS progression. Our findings implied that Sch treatment inhibited the proliferation and migration of VSMCs, and suppressed the ROS production and inflammatory cytokines up-regulation of VSMCs and macrophages. Moreover, Sch reduced lipid uptake and foam cell formation through downregulating LOX-1. Mechanistically, we found that Sch can inhibit the activation of JAK2/STAT3 signaling by targeting JAK2, and arrest cell cycle in GO/G1 phase. In summary, Sch can inhibit VSMCs proliferation and migration by arresting cell cycle and targeting JAK2 to regulating the JAK2/STAT3 pathway. Sch may serve as a potential drug for patients with AS.

Interleukin-6 serves as a critical factor in various cancer progression and therapy

Interleukin-6 (IL-6), a pro-inflammatory cytokine, plays a crucial role in host immune defense and acute stress responses. Moreover, it modulates various cellular processes, including proliferation, apoptosis, angiogenesis, and differentiation. These effects are facilitated by various signaling pathways, particularly the signal transducer and activator of transcription 3 (STAT3) and Janus kinase 2 (JAK2). However, excessive IL-6 production and dysregulated signaling are associated with various cancers, promoting tumorigenesis by influencing all cancer hallmarks, such as apoptosis, survival, proliferation, angiogenesis, invasiveness, metastasis, and notably, metabolism. Emerging evidence indicates that selective inhibition of the IL-6 signaling pathway yields therapeutic benefits across diverse malignancies, such as multiple myeloma, prostate, colorectal, renal, ovarian, and lung cancers. Targeting key components of IL-6 signaling, such as IL-6Rs, gp130, STAT3, and JAK via monoclonal antibodies (mAbs) or small molecules, is a heavily researched approach in preclinical cancer studies. The purpose of this study is to offer an overview of the role of IL-6 and its signaling pathway in various cancer types. Furthermore, we discussed current preclinical and clinical studies focusing on targeting IL-6 signaling as a therapeutic strategy for various types of cancer.

Tumor-associated astrocytes promote tumor progression of Sonic Hedgehog medulloblastoma by secreting lipocalin-2

Sonic Hedgehog (SHH) subgroup of medulloblastoma (MB) accounts for about 25% of all subgroups of MB. Tumor microenvironment (TME) may play a key role in the tumor progression and therapeutic resistance. Tumor-associated astrocytes (TAAs) are reshaped to drive tumor progression through multiple paracrine signals. However, the mechanism by which TAAs modulate MB cells remains elusive. Here, we illuminated that TAAs showed a specific and dynamic pattern during SHH-MB development. Most TAAs gathered to the tumor margin during the tumor progression, rather than evenly distributed in the early-stage tumors. We further demonstrated that lipocalin-2 (LCN2) secreted by TAAs could promote the tumor growth and was correlated with the poor prognosis of MB patients. Knocking down LCN2 in TAAs in vitro impeded the proliferation and migration abilities of MB cells. In addition, we identified that TAAs accelerated the tumor growth by secreting LCN2 via STAT3 signaling pathway. Accordingly, blockade of STAT3 signaling by its inhibitor WP1066 and AAV-Lcn2 shRNA, respectively, in TAAs abrogated the effects of LCN2 on tumor progression in vitro and in vivo. In summary, we for the first time clarified that LCN2, secreted by TAAs, could promote MB tumor progression via STAT3 pathway and has potential prognostic value. Our findings unveiled a new sight in reprogramming the TME of SHH-MB and provided a potential therapeutic strategy targeting TAAs.

The Human Placental Amniotic Membrane Mesenchymal-Stromal-Cell-Derived Conditioned Medium Inhibits Growth and Promotes Apoptosis of Human Cholangiocarcinoma Cells In Vitro and In Vivo by Suppressing IL-6/JAK2/STAT3 Signaling

Mesenchymal stromal cells (MSCs) have recently been shown to play an important role in the growth and progression of many solid tumors, including cholangiocarcinoma (CCA). The human placental amniotic membrane (hPAM) is one of the most favorable sources of MSCs due to its availability and non-invasive harvesting procedure. However, the role of human placental amniotic membrane mesenchymal stromal cells (hPAMSCs) in the growth and progression of human CCA has not yet been determined. This study investigates the effects of conditioned medium derived from hPAMSCs (PA-CM) on the properties of three human CCA cell lines and explores possible mechanisms of action. Varying concentrations of PA-CM were used to treat CCA cells to determine their effects on the proliferation and apoptosis of CCA cells. The results showed that PA-CM inhibited the proliferation and colony-forming capacity of KKU100, KKU213A, and KKU213B cells. PA-CM also promoted the apoptosis of these CCA cells by causing the loss of mitochondrial membrane potential. Western Blotting confirmed that PA-CM induced CCA cell apoptosis by increasing the levels of the Bax/Bcl-2 ratio, cleaved caspase 3, and cleaved PARP, possibly by inhibiting the IL-6/JAK2/STAT3 signaling pathway. Moreover, our in vivo study also confirmed the suppressive effect of hPAMSCs on CCA cells by showing that PA-CM reduced tumor volume in nude mice transplanted with human CCA cells. Taken together, our results demonstrate that PA-CM has potent tumor-suppressive effects on human CCA cells and could potentially be used in combination with chemotherapy to develop a more effective treatment for CCA patients.

LncRNA SNHG6 role in clinicopathological parameters in cancers

RNA sequencing has revealed that a substantial portion of the human genome undergoes transcription, yet a minimal fraction of these transcripts translates into proteins. LncRNAs, RNA molecules less than 200 nt in length, once deemed as transcriptional noise, have now emerged as crucial regulators of numerous cellular processes. This review focuses on the lncRNA SNHG6, aiming to elucidate its biogenesis, the pivotal roles it plays, and its mechanisms in facilitating the hallmarks of cancer. A comprehensive literature review and analysis were undertaken to delve into the biogenesis of SNHG6, its roles in cellular processes, and the mechanisms through which it contributes to the hallmarks of cancer. SNHG6 is a notable lncRNA, observed to be overexpressed in various cancer types; its perturbation has been linked to tumor progression, emphasizing its significance in oncogenesis. This lncRNA contributes to a range of cellular aberrations, influencing transcriptional, post-transcriptional, and epigenetic processes of mRNA, ultimately driving cancerous transformations. LncRNA SNHG6 serves as a potential biomarker and therapeutic target due to its association with tumorigenesis. Understanding its mechanism and role in cancer can pave the way for novel diagnostic and therapeutic strategies.

Molecular mechanisms of microRNA-216a during tumor progression

MicroRNAs (miRNAs) as the members of non-coding RNAs family are involved in post-transcriptional regulation by translational inhibiting or mRNA degradation. They have a critical role in regulation of cell proliferation and migration. MiRNAs aberrations have been reported in various cancers. Considering the importance of these factors in regulation of cellular processes and their high stability in body fluids, these factors can be suggested as suitable non-invasive markers for the cancer diagnosis. MiR-216a deregulation has been frequently reported in different cancers. Therefore, in the present review we discussed the molecular mechanisms of the miR-216a during tumor progression. It has been reported that miR-216a mainly functioned as a tumor suppressor through the regulation of signaling pathways and transcription factors. This review paves the way to suggest the miR-216a as a probable therapeutic and diagnostic target in cancer patients.

Molecular mechanisms underlying the action of carcinogens in gastric cancer with a glimpse into targeted therapy

BACKGROUND

Gastric cancer imposes a substantial global health burden despite its overall incidence decrease. A broad spectrum of inherited, environmental and infectious factors contributes to the development of gastric cancer. A profound understanding of the molecular underpinnings of gastric cancer has lagged compared to several other tumors with similar incidence and morbidity rates, owing to our limited knowledge of the role of carcinogens in this malignancy. The International Agency for Research on Cancer (IARC) has classified gastric carcinogenic agents into four groups based on scientific evidence from human and experimental animal studies. This review aims to explore the potential comprehensive molecular and biological impacts of carcinogens on gastric cancer development and their interactions and interferences with various cellular signaling pathways.

CONCLUSIONS

In this review, we highlight recent clinical trial data reported in the literature dealing with different ways to target various carcinogens in gastric cancer. Moreover, we touch upon other multidisciplinary therapeutic approaches such as surgery, adjuvant and neoadjuvant chemotherapy. Rational clinical trials focusing on identifying suitable patient populations are imperative to the success of single-agent therapeutics. Novel insights regarding signaling pathways that regulate gastric cancer can potentially improve treatment responses to targeted therapy alone or in combination with other/conventional treatments. Preventive strategies such as control of H. pylori infection through eradication or immunization as well as dietary habit and lifestyle changes may reduce the incidence of this multifactorial disease, especially in high prevalence areas. Further in-depth understanding of the molecular mechanisms involved in the role of carcinogenic agents in gastric cancer development may offer valuable information and update state-of-the-art resources for physicians and researchers to explore novel ways to combat this disease, from bench to bedside. A schematic outlining of the interaction between gastric carcinogenic agents and intracellular pathways in gastric cancer H. pylori stimulates multiple intracellular pathways, including PI3K/AKT, NF-κB, Wnt, Shh, Ras/Raf, c-MET, and JAK/STAT, leading to epithelial cell proliferation and differentiation, apoptosis, survival, motility, and inflammatory cytokine release. EBV can stimulate intracellular pathways such as the PI3K/Akt, RAS/RAF, JAK/STAT, Notch, TGF-β, and NF-κB, leading to cell survival and motility, proliferation, invasion, metastasis, and the transcription of anti-apoptotic genes and pro-inflammatory cytokines. Nicotine and alcohol can lead to angiogenesis, metastasis, survival, proliferation, pro-inflammatory, migration, and chemotactic by stimulating various intracellular signaling pathways such as PI3K/AKT, NF-κB, Ras/Raf, ROS, and JAK/STAT. Processed meat contains numerous carcinogenic compounds that affect multiple intracellular pathways such as sGC/cGMP, p38 MAPK, ERK, and PI3K/AKT, leading to anti-apoptosis, angiogenesis, metastasis, inflammatory responses, proliferation, and invasion. Lead compounds may interact with multiple signaling pathways such as PI3K/AKT, NF-κB, Ras/Raf, DNA methylation-dependent, and epigenetic-dependent, leading to tumorigenesis, carcinogenesis, malignancy, angiogenesis, DNA hypermethylation, cell survival, and cell proliferation. Stimulating signaling pathways such as PI3K/Akt, RAS/RAF, JAK/STAT, WNT, TGF-β, EGF, FGFR2, and E-cadherin through UV ionizing radiation leads to cell survival, proliferation, and immortalization in gastric cancer. The consequence of PI3K/AKT, NF-κB, Ras/Raf, ROS, JAK/STAT, and WNT signaling stimulation by the carcinogenic component of Pickled vegetables and salted fish is the Warburg effect, tumorigenesis, angiogenesis, proliferation, inflammatory response, and migration.

A Deep Neural Network for Gastric Cancer Prognosis Prediction Based on Biological Information Pathways

Background

Gastric cancer (GC) is one of the deadliest cancers in the world, with a 5-year overall survival rate of lower than 20% for patients with advanced GC. Genomic information is now frequently employed for precision cancer treatment due to the rapid advancements of high-throughput sequencing technologies. As a result, integrating multiomics data to construct predictive models for the GC patient prognosis is critical for tailored medical care.

Results

In this study, we integrated multiomics data to design a biological pathway-based gastric cancer sparse deep neural network (GCS-Net) by modifying the P-NET model for long-term survival prediction of GC. The GCS-Net showed higher accuracy (accuracy = 0.844), area under the curve (AUC = 0.807), and F1 score (F1 = 0.913) than traditional machine learning models. Furthermore, the GCS-Net not only enables accurate patient survival prognosis but also provides model interpretability capabilities lacking in most traditional deep neural networks to describe the complex biological process of prognosis. The GCS-Net suggested the importance of genes (UBE2C, JAK2, RAD21, CEP250, NUP210, PTPN1, CDC27, NINL, NUP188, and PLK4) and biological pathways (Mitotic Anaphase, Resolution of Sister Chromatid Cohesion, and SUMO E3 ligases) to GC, which is consistent with the results revealed in biological- and medical-related studies of GC.

Conclusion

The GCS-Net is an interpretable deep neural network built using biological pathway information whose structure represents a nonlinear hierarchical representation of genes and biological pathways. It can not only accurately predict the prognosis of GC patients but also suggest the importance of genes and biological pathways. The GCS-Net opens up new avenues for biological research and could be adapted for other cancer prediction and discovery activities as well.

Human chorion-derived mesenchymal stem cells suppress JAK2/STAT3 signaling and induce apoptosis of cholangiocarcinoma cell lines

Cholangiocarcinoma (CCA) is an aggressive malignancy arising from the damaged epithelial cells of the biliary tract. Previous studies have reported that the multi-potent mesenchymal stem cells (MSCs) activate a series of tumor signaling pathways by releasing several cytokines to influence tumor cell development. However, the roles and mechanisms of human chorion-derived MSCs (CH-MSCs) in cholangiocarcinoma progression have not been fully addressed. This present study aims to examine the effects of conditioned media derived from CH-MSCs (CH-CM) on CCA cell lines and investigate the respective underlying mechanism of action. For this purpose, MSCs were isolated from chorion tissue, and three cholangiocarcinoma cell lines, namely KKU100, KKU213A, and KKU213B, were used. MTT assay, annexin V/PI analysis, and JC-1 staining were used to assess the effects of CH-CM on proliferation and apoptosis of CCA cells, respectively. Moreover, the effect of CH-CM on caspase-dependent apoptotic pathways was also evaluated. The western blotting assay was also used for measuring the expression of JAK2/STAT3 signaling pathway-associated proteins. The results showed that CH-CM suppressed proliferation and promoted apoptosis of CCA cell lines. CH-CM treatment-induced loss of mitochondrial membrane potential (∆Ψm) in CCA cell lines. The factors presented in the CH-CM also inhibited JAK2/STAT3 signaling, reduced the expression of BCL-2, and increased BAX expression in CCA cells. In conclusion, our study suggests that the CH-CM has a potent anti-cancer effect on cholangiocarcinoma cells and thus provides opportunities for use in alternative cell therapy or in combination with a conventional chemotherapeutic drug to increase the efficiency of CCA treatment.

The emerging role of miR-653 in human cancer

MicroRNAs (miRNAs) refer to a family of non-coding RNA with ~22 nucleotides in length. A high number of studies show evidence that deregulation in miRNAs expression could be implicated in the processes of many pathologies such as cancer, hypoxia, and stroke. Herein, we aimed to summarize the miR-653 expression level and molecular mechanisms through which it functions in human cancer. It was found that variations in miR-653 expression are linked to tumor aggressiveness and unfavorable prognosis in human cancer, and it plays an inhibitory effect in some types of cancer, such as breast, cervical, liver, renal, and lung cancers. In contrast, it plays an acceleratory impact in some other cancers, such as bladder and prostate cancers. In gastric cancer, the role played by miR-653 is still controversial and will need to be elucidated in future studies. Future studies could definitely establish targeting miR-653 as a novel strategy in human cancer, from diagnosis to effective treatment.

A first-in-human Phase I trial of the oral p-STAT3 inhibitor WP1066 in patients with recurrent malignant glioma

Aim: To ascertain the maximum tolerated dose (MTD)/maximum feasible dose (MFD) of WP1066 and p-STAT3 target engagement within recurrent glioblastoma (GBM) patients. Patients & methods: In a first-in-human open-label, single-center, single-arm 3 + 3 design Phase I clinical trial, eight patients were treated with WP1066 until disease progression or unacceptable toxicities. Results: In the absence of significant toxicity, the MFD was identified to be 8 mg/kg. The most common adverse event was grade 1 nausea and diarrhea in 50% of patients. No treatment-related deaths occurred; 6 of 8 patients died from disease progression and one was lost to follow-up. Of 8 patients with radiographic follow-up, all had progressive disease. The longest response duration exceeded 3.25 months. The median progression-free survival (PFS) time was 2.3 months (95% CI: 1.7 months-NA months), and 6-month PFS (PFS6) rate was 0%. The median overall survival (OS) rate was 25 months (95% CI: 22.5 months-NA months), with an estimated 1-year OS rate of 100%. Pharmacokinetic (PK) data demonstrated that at 8 mg/kg, the T1/2 was 2-3 h with a dose dependent increase in the Cmax. Immune monitoring of the peripheral blood demonstrated that there was p-STAT3 suppression starting at a dose of 1 mg/kg. Conclusion: Immune analyses indicated that WP1066 inhibited systemic immune p-STAT3. WP1066 had an MFD identified at 8 mg/kg which is the target allometric dose based on prior preclinical modeling in combination with radiation therapy and a Phase II study is being planned for newly diagnosed MGMT promoter unmethylated glioblastoma patients.

STAT3 pathway in cancers: Past, present, and future

Signal transducer and activator of transcription 3 (STAT3), a member of the STAT family, discovered in the cytoplasm of almost all types of mammalian cells, plays a significant role in biological functions. The duration of STAT3 activation in normal tissues is a transient event and is strictly regulated. However, in cancer tissues, STAT3 is activated in an aberrant manner and is induced by certain cytokines. The continuous activation of STAT3 regulates the expression of downstream proteins associated with the formation, progression, and metastasis of cancers. Thus, elucidating the mechanisms of STAT3 regulation and designing inhibitors targeting the STAT3 pathway are considered promising strategies for cancer treatment. This review aims to introduce the history, research advances, and prospects concerning the STAT3 pathway in cancer. We review the mechanisms of STAT3 pathway regulation and the consequent cancer hallmarks associated with tumor biology that are induced by the STAT3 pathway. Moreover, we summarize the emerging development of inhibitors that target the STAT3 pathway and novel drug delivery systems for delivering these inhibitors. The barriers against targeting the STAT3 pathway, the focus of future research on promising targets in the STAT3 pathway, and our perspective on the overall utility of STAT3 pathway inhibitors in cancer treatment are also discussed.

Glycosylation of Methylflavonoids in the Cultures of Entomopathogenic Filamentous Fungi as a Tool for Obtaining New Biologically Active Compounds

Flavonoid compounds are secondary plant metabolites with numerous biological activities; they naturally occur mainly in the form of glycosides. The glucosyl moiety attached to the flavonoid core makes them more stable and water-soluble. The methyl derivatives of flavonoids also show increased stability and intestinal absorption. Our study showed that such flavonoids can be obtained by combined chemical and biotechnological methods with entomopathogenic filamentous fungi as glycosylation biocatalysts. In the current paper, two flavonoids, i.e., 2′-hydroxy-4-methylchalcone and 4′-methylflavone, have been synthesized and biotransformed in the cultures of two strains of entomopathogenic filamentous fungi Isaria fumosorosea KCH J2 and Beauveria bassiana KCH J1.5. Biotransformation of 2′-hydroxy-4-methylchalcone resulted in the formation of two dihydrochalcone glucopyranoside derivatives in the culture of I. fumosorosea KCH J2 and chalcone glucopyranoside derivative in the case of B. bassiana KCH J1.5. 4′-Methylflavone was transformed in the culture of I. fumosorosea KCH J2 into four products, i.e., 4′-hydroxymethylflavone, flavone 4′-methylene-O-β-d-(4″-O-methyl)-glucopyranoside, flavone 4′-carboxylic acid, and 4′-methylflavone 3-O-β-d-(4″-O-methyl)-glucopyranoside. 4′-Methylflavone was not efficiently biotransformed in the culture of B. bassiana KCH J1.5. The computer-aided simulations based on the chemical structures of the obtained compounds showed their improved physicochemical properties and antimicrobial, anticarcinogenic, hepatoprotective, and cardioprotective potential.

IL4Rα and IL13Rα1 Are Involved in the Development of Human Gallbladder Cancer

Background: Gallbladder cancer is commonly associated with inflammation, which indicates that inflammation-related cytokines and cytokine receptors are related to the progression of gallbladder cancers. Interleukin 4 (IL4) is a well-known cytokine that promotes the differentiation of naive helper T cells (Th0) to T helper type 2 cells (Th2). IL13 is a cytokine that is secreted by Th2 cells. IL4 and IL13 are closely related in immune responses. However, the role of IL4Rα and IL13Rα1 signaling pathway has not been fully understood in the development of gallbladder cancer. Methods: In human gallbladder carcinomas, the expression of IL4Rα and IL13Rα1 were evaluated with immunohistochemical staining in tissue microarray tissue sections. After knockdown of IL4Rα or IL13Rα1, cell assays to measure the proliferation and apoptosis and Western blotting analysis were conducted in SNU308 human gallbladder cancer cells. Since Janus kinases2 (JAK2) was considered as one of the down-stream kinases under IL4Rα and IL13Rα1 complex, the same kinds of experiments were performed in SNU308 cells treated with AZD1480, Janus-associated kinases2 (JAK2) inhibitor, to demonstrate the cytotoxic effect of AZD1480 in SNU308 cells. Results: Immunohistochemical expression of IL4Rα was significantly associated with the expression of IL13Rα1 in human carcinoma tissue. In univariate analysis, nuclear expression of IL4Rα, cytoplasmic expression of IL4Rα, nuclear expression of IL13Rα1, and cytoplasmic expression of IL13Rα1 were significantly associated with shorter overall survival and shorter relapse-free survival. Multivariate analysis revealed nuclear expression of IL4Rα as an independent poor prognostic indicator of overall survival and relapse-free survival. Then, we found that knockdown of IL4Rα or IL13Rα1 decreased viability and induced apoptosis in SNU308 cells via activation of FOXO3 and similarly, AZD1480 decreased viability and induced apoptosis in SNU308 cells with dose dependent manner. Conclusions: Taken together, our results suggest that IL4Rα and IL13Rα1 might be involved in the development of human gallbladder cancer cells and IL4Rα and IL13Rα1 complex/JAK2 signaling pathway could be efficient therapeutic targets for gallbladder cancer treatment.

Kinases and therapeutics in pathogen mediated gastric cancer

INTRODUCTION

Many pathogens have coexisted with humans for millennia and can cause chronic inflammation which is the cause of gastritis. Gastric cancer (GC) is associated with 8.8% of cancer related deaths, making it one of the leading causes of cancer related deaths worldwide. This review is intended to give brief information about Helicobacter pylori (H. pylori), Epstein-Barr virus (EBV), human cytomegalovirus (HCMV) role in GC and associated kinases. These organisms can trigger multiple cellular pathways aiming for unnatural cellular proliferation, apoptosis, migration and inflammatory response. Kinases also can activate and deactivate the signalling leading to aforementioned pathways. Therefore, studying kinases is inevitable.

MATERIAL AND METHODS

This review is the comprehensive collection of information from different data sources such as journals, book, book chapters and verified online information.

CONCLUSION

Kinase amplifications could be used as diagnostic, prognostic, and predictive biomarkers in various cancer types. Hence targeting kinase and related signalling molecules could be considered as a potential approach to prevent cancer through these organisms. Here we summarize the brief information about the role of kinases, signalling and their therapeutics in GC concerning H. pylori, EBV and HCMV.

Peripheral Cytokine Levels as a Prognostic Indicator in Gastric Cancer: A Review of Existing Literature

Although strong connections exist between the carcinogenesis of gastric cancer and chronic inflammation, gastric cancer is unique in that the chronic gastritis which frequently precedes carcinogenesis is strongly associated with H. pylori infection. The interplay between H. pylori virulence factors and host immune cells is complex but culminates in the activation of inflammatory pathways and transcription factors such as NF-κB, STAT3, and AP-1, all of which upregulate cytokine production. Due to the key role of cytokines in modulating the immune response against tumour cells as well as possibly stimulating tumour growth and proliferation, different patterns of cytokine secretion may be associated with varying patient outcomes. In relation to gastric cancer, interleukin-6, 8, 10, 17A, TNF, and IFN-γ may have pro-tumour properties, although interleukin-10, TNF, and IFN-γ may have anti-tumour effects. However, due to the lack of studies investigating patient outcomes, only a link between higher interleukin-6 levels and poorer prognosis has been demonstrated. Further investigations which link peripheral cytokine levels to patient prognosis may elucidate important pathological mechanisms in gastric cancer which adversely impact patient survival and allow treatments targeting these processes to be developed.

Comprehensive analysis of prognostic genes in gastric cancer

Background: Gastric cancer is associated with high mortality, and effective methods for predicting prognosis are lacking. We aimed to identify potential prognostic markers associated with the development of gastric cancer through bioinformatic analyses.

Methods: Gastric cancer-associated gene expression profiles were obtained from The Cancer Genome Atlas and Gene Expression Omnibus databases. The key genes involved in the development of gastric cancer were obtained by differential expression analysis, coexpression analysis, and short time-series expression miner (STEM) analysis. The potential prognostic value of differentially expressed genes was further evaluated using a Cox regression model and risk scores. Hierarchical clustering was applied to validate the impact of key genes on the overall survival of gastric cancer patients.

Results: A total of 1381 genes were consistently dysregulated in the development of gastric cancer. Among them, 186 genes affected the overall survival of gastric cancer patients. The following genes had areas under the receiver operating characteristic curve greater than 0.9 in both datasets and were therefore considered key genes: ADAM12, CEP55, LRFN4, INHBA, ADH1B, DPT, FAM107A, and LOC100506388. LRFN4, DPT, and LOC100506388 were identified as potential prognostic genes for gastric cancer through a nomogram. Overexpression of LRFN4 and LOC100506388 was associated with a higher risk of gastric cancer. Finally, we found that tumors were infiltrated with high levels of Th2 cells and mast cells, and the infiltration levels were associated with overall survival in gastric cancer patients.

Conclusions: We found that key dysregulated genes may have a prognostic value for the development of gastric cancer.

MiR-133b regulates oxidative stress injury of trophoblasts in preeclampsia by mediating the JAK2/STAT3 signaling pathway

Preeclampsia (PE) is a pregnancy-related syndrome. Aberrant placental microRNAs (miRNAs) expression might associate with PE, including miR-133b. However, its role in the pathogenesis of preeclampsia remains elusive. Therefore, this study explored the role of miR-133b in oxidative stress injury of trophoblasts in preeclampsia (PE) by mediating the JAK2/STAT3 signaling pathway. Placental tissues were collected from PE patients to detect the expression of miR-133b and JAK2/STAT3. Then, in vitro experiments were performed on human extravillous trophoblast-derived HTR-8/SVneo cells, which were divided into Normal, hypoxia/reoxygenation (H/R), H/R + miR-NC, H/R + miR-133b inhibitor, H/R + JAK2 siRNA and H/R + miR-133b inhibitor + JAK2 siRNA groups. Cell invasion and migration abilities were detected by Transwell and wound healing assays, while apoptosis was detected by flow cytometry. The intracellular oxidative stress levels were also measured. Furthermore, the expression of miR-133b and the JAK2/STAT3 pathway was determined by qRT-PCR and Western blotting. We found that miR-133b was up-regulated, with decreases in JAK2 and p-STAT3/STAT3 in placental tissues of PE patients. Additionally, HTR8/SVneo cells in the H/R group had decreased invasion and migration abilities with increased apoptotic rates and oxidative stress levels. Moreover, the expression of miR-133b was up-regulated with decreases in p-JAK2 and p-STAT3 in H/R-treated HTR8/SVneo cells. These indicators in the H/R + miR-133b inhibitor group were ameliorated in comparison with those in the H/R group but deteriorated in the H/R + JAK2 siRNA group. Moreover, JAK2 siRNA reversed the positive effect of the miR-133b inhibitor on the invasion and migration abilities of trophoblasts. In summary, inhibiting miR-133b may improve oxidative stress injury to promote the migration and invasion of trophoblasts and suppress apoptosis by activating the JAK2/STAT3 pathway.

Gastrokine 2 Regulates the Antitumor Effect of JAK2/STAT3 Pathway in Gastric Cancer

GKN2 (gastrokine 2) mainly plays a regulatory role in gastric mucosal defense and cell protection mechanisms, and its role in gastric cancer has not been thoroughly elucidated. Immunohistochemistry was used to detect GKN2 and TFF1 expressions in 90 gastric cancer tissues, 48 neoplastic resection margins, and 22 normal gastric mucosa epithelia. It showed that the downregulation of GKN2 and TFF1 expressions in gastric cancer tissues was significantly different from that in adjacent normal gastric tissues and distal gastric mucosal tissues. Nevertheless, correlation analysis showed that GKN2 expression in gastric cancer tissues was independent of TFF1 expression. After overexpression of GKN2 was constructed in human gastric cancer cell line MKN28 with the Ad-GFP-GKN2 transfected, cell viability was measured by CCK-8 assay, and migration and invasion ability were analyzed by transwell migration assay and transwell invasion assay. It indicated that overexpression of GKN2 significantly reduced the viability of MKN28 and SGC7901 cells. Overexpression of GKN2 could also inhibit the migration and invasion ability in MKN28 and SGC7901 cells. In addition, upregulation of GKN2 can inactivate the JAK2/STAT3 pathway. Our data suggest that GKN2 and TFF1 play the antitumor role in gastric carcinoma, and TFF1 may not interact or cooperate with GKN2. GKN2 overexpression can inhibit the growth and metastasis by downregulating the JAK2/STAT3 pathway in gastric cancer cells.

SENP1-mediated deSUMOylation of JAK2 regulates its kinase activity and platinum drug resistance

The JAK2/STAT pathway is hyperactivated in many cancers, and such hyperactivation is associated with a poor clinical prognosis and drug resistance. The mechanism regulating JAK2 activity is complex. Although translocation of JAK2 between nucleus and cytoplasm is an important regulatory mechanism, how JAK2 translocation is regulated and what is the physiological function of this translocation remain largely unknown. Here, we found that protease SENP1 directly interacts with and deSUMOylates JAK2, and the deSUMOylation of JAK2 leads to its accumulation at cytoplasm, where JAK2 is activated. Significantly, this novel SENP1/JAK2 axis is activated in platinum-resistant ovarian cancer in a manner dependent on a transcription factor RUNX2 and activated RUNX2/SENP1/JAK2 is critical for platinum-resistance in ovarian cancer. To explore the application of anti-SENP1/JAK2 for treatment of platinum-resistant ovarian cancer, we found SENP1 deficiency or treatment by SENP1 inhibitor Momordin Ic significantly overcomes platinum-resistance of ovarian cancer. Thus, this study not only identifies a novel mechanism regulating JAK2 activity, but also provides with a potential approach to treat platinum-resistant ovarian cancer by targeting SENP1/JAK2 pathway.

Podocarpusflavone A inhibits cell growth of skin cutaneous melanoma by suppressing STAT3 signaling

BACKGROUND

JAK2/STAT3 pathway is involved in the development and progression of melanoma once DNA damage is caused by environment and genetic factors.

OBJECTIVE

Here, we aimed to identify novel inhibitor of JAK2/STAT3 pathway and reveal the underlying mechanisms.

METHODS

Eighty MedChemExpress compounds were screened by using STAT3-Luc reporter in A375 cells. Podocarpusflavone A (PCFA) was identified as an inhibitor of STAT3, which was further verified in four melanoma cell lines. The anti-melanoma effects and mechanism of PCFA were examined and explored in melanoma cells and mouse xenograft models by using Western blot and cell-counting kit-8 assay.

RESULTS

PCFA exhibited potent inhibitory effects on melanoma both in vitro and in vivo. PCFA inhibited the activation of STAT3 through suppressing the phosphorylation of JAK2, and then restrained cell cycle and induced apoptosis of melanoma cells.

CONCLUSION

PCFA inhibits melanoma growth via the inhibition of JAK2/STAT3 pathway, which provides a promising therapeutic strategies of melanoma treatment.

DDX5 Silencing Suppresses the Migration of Basal cell Carcinoma Cells by Downregulating JAK2/STAT3 Pathway

Basal cell carcinoma is driven by the aberrant activation of hedgehog signaling. DEAD (Asp-Glu-Ala-Asp) box protein 5 is frequently overexpressed in human cancer cells and associated with the tumor growth and invasion. The purpose of this study was to investigate the role of DEAD (Asp-Glu-Ala-Asp) box protein 5 in the growth, migration, and invasion of basal cell carcinoma. The role of DEAD (Asp-Glu-Ala-Asp) box protein 5 was detected by quantitative real-time polymerase chain reaction, Western blot, and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling assay in basal cell carcinoma cells. The associations between JAK2/STAT3 pathway and DEAD (Asp-Glu-Ala-Asp) box protein 5 were analyzed in basal cell carcinoma cells. Results showed that DEAD (Asp-Glu-Ala-Asp) box protein 5 is overexpressed in basal cell carcinoma cells. DEAD (Asp-Glu-Ala-Asp) box protein 5 knockdown inhibited the migration and invasion of basal cell carcinoma cells. DEAD (Asp-Glu-Ala-Asp) box protein 5 knockdown increased the apoptosis of basal cell carcinoma cells induced by tunicamycin. Results found that DEAD (Asp-Glu-Ala-Asp) box protein 5 knockdown increased JAK2 and STAT3 expression in basal cell carcinoma cells. JAK2 inhibitor decreased STAT3 expression and abolished the inhibitory effects of DEAD (Asp-Glu-Ala-Asp) box protein 5 silencing on migration and invasion in basal cell carcinoma cells. In conclusion, these results indicate that DEAD (Asp-Glu-Ala-Asp) box protein 5 is a potential target for inhibiting basal cell carcinoma cells growth, migration, and invasion by downregulating JAK2/STAT3 pathway.

Inhibition of the SRC Kinase HCK Impairs STAT3-Dependent Gastric Tumor Growth in Mice

Persistent activation of the latent transcription factor STAT3 is observed in gastric tumor epithelial and immune cells and is associated with a poor patient prognosis. Although targeting STAT3-activating upstream kinases offers therapeutically viable targets with limited specificity, direct inhibition of STAT3 remains challenging. Here we provide functional evidence that myeloid-specific hematopoietic cell kinase (HCK) activity can drive STAT3-dependent epithelial tumor growth in mice and is associated with alternative macrophage activation alongside matrix remodeling and tumor cell invasion. Accordingly, genetic reduction of HCK expression in bone marrow-derived cells or systemic pharmacologic inhibition of HCK activity suppresses alternative macrophage polarization and epithelial STAT3 activation, and impairs tumor growth. These data validate HCK as a molecular target for the treatment of human solid tumors harboring excessive STAT3 activity.

Interleukin4Rα (IL4Rα) and IL13Rα1 Are Associated with the Progress of Renal Cell Carcinoma through Janus Kinase 2 (JAK2)/Forkhead Box O3 (FOXO3) Pathways

Specific kinds of interleukin (IL) receptors are known to mediate lymphocyte proliferation and survival. However, recent reports have suggested that the high expression of IL4Rα and IL13Rα1 in tumor tissue might be associated with tumorigenesis in several kinds of tumor. We found that a significant association between mRNA level of IL4Rα or IL13Rα1 and the poor prognosis of renal cell carcinoma (RCC) from the public database (http://www.oncolnc.org/). Then, we evaluated the clinicopathological significance of the immunohistochemical expression of IL4Rα and IL13Rα1 in 199 clear cell RCC (CCRCC) patients. The individual and co-expression patterns of IL4Rα and IL13Rα1 were significantly associated with cancer-specific survival (CSS) and relapse-free survival (RFS) in univariate analysis. Multivariate analysis indicated IL4Rα-positivity and co-expression of IL4Rα and IL13Rα1 as the independent indicators of shorter CSS and RFS of CCRCC patients. For the in vitro evaluation of the oncogenic role of IL4Rα and IL13Rα1 in RCC, we knock-downed IL4Rα or IL13Rα1 and observed that the cell proliferation rate was decreased, and the apoptosis rate was increased in A498 and ACHN cells. Furthermore, we examined the possible role of Janus kinase 2 (JAK2), well-known down-stream tyrosine kinase under the heterodimeric receptor complex of IL4Rα and IL13Rα1. Interestingly, JAK2 interacted with Forkhead box O3 (FOXO3) to cause tyrosine-phosphorylation of FOXO3. Silencing IL4Rα or JAK2 in A498 and ACHN cells reduced the interaction between JAK2 and FOXO3. Moreover, pharmacological inhibition of JAK2 induced the nuclear localization of FOXO3, leading to increase apoptosis and decrease cell proliferation rate in A498 and ACHN cells. Taken together, these results suggest that IL4Rα and IL13Rα1 might be involved in the progression of RCC through JAK2/FOXO3 pathway, and their expression might be used as the novel prognostic factor and therapeutic target for RCC patients.

Molecular analysis of V617F mutation in Janus kinase 2 gene of breast cancer patients

BACKGROUND

Breast cancer is a multifactorial disease with the highest frequency in females. Genetic and environmental factors can cause mutation in several genes like tyrosine kinase, JAK2 gene which may initiate cancer. Molecular analysis of mutations in the JAK2 gene along with determination of environmental, clinical and haematological risk factors associated with breast cancer patients is need of hour to improve patient's healthcare. Somatic JAK2 valine-to-phenylalanine (617 codon) mutation is one of the widely prevalent mutations.

METHODS

Blood was collected from seventy breast cancer patients after their consent. The questionnaire included risk factors, age group, locality, number of children, tumor type, family history, time of initial diagnosis, no of cycles/month, water conditions and exposure to radiations. Molecular analysis were carried out from genomic DNA using Sanger sequencing and allele-specific PCR to check the V617F point mutation.

RESULTS

The breast cancer risk factors includes unfiltered water (68.57%), urban (58.57%), menopause (55.71%), family history of cancer (18.57%), tumor grades (II, 37.14% and III, 35.71%), consanguineous marriages (44.28%) and having more than 3-4 children (45.71%). Prevalence of breast cancer was higher after the age of 35 and maximum at 35-50. In allele-specific PCR of 70 patients, 25 patients were wild type (229 bp), 25 patients were with partially deleted gene (200 bp), and 20 patient had shown no or less than 40 bp size fragments. In Sanger's sequencing of 70 BC cases, 18% were found to be positive for V617F point mutation, including 6 homozygous (T/T) and 7 heterozygous (G/T) mutations at nucleotide position 1849 in exon 14 of the JAK2 gene.

CONCLUSIONS

Environmental and clinical risk factors were associated with breast cancer which can be overcome by improving awareness of associated risks, health facilities and reducing stress.

Knockdown of TRIM66 inhibits cell proliferation, migration and invasion in colorectal cancer through JAK2/STAT3 pathway

Colorectal cancer (CRC) is one of the most common malignancies in the world. Emerging evidence has shown that dysregulation of tripartite motif (TRIM) family proteins is strongly correlated with the tumorigenesis of CRC. Here, we evaluated the biological roles of TRIM66, a member of TRIM family, in the progression of CRC. The results demonstrated that TRIM66 was markedly up-regulated in both CRC tissues and cell lines. To further investigate the functions of TRIM66 in CRC, CRC cells were infected with lentivirus expressing anti-TRIM66 shRNA (sh-TRIM66) or control lentivirus (sh-con). We found that knockdown of TRIM66 significantly inhibited cell proliferation, migration, invasion of CRC cells. TRIM66 knockdown also suppressed epithelial-mesenchymal transition (EMT), as proved by the increased E-cadherin expression and decreased expressions of N-cadherin and vimentin. Furthermore, TRIM66 knockdown markedly inhibited tumor growth in a mouse xenograft model. Knockdown of TRIM66 reduced the activation of JAK2/STAT3 signaling pathway in CRC cells. Treatment with AG490, an inhibitor of JAK2/STAT3 signaling pathway, enhanced the inhibitory effects of TRIM66 knockdown on cell proliferation, migration and invasion. These findings suggested that knockdown of TRIM66 exhibited anti-tumor activity through inhibiting the JAK2/STAT3 signaling pathway in CRC cells.

MicroRNA-7 directly targets Reg1 in pancreatic cells

Regenerating islet-derived (Reg) proteins, which were first discovered in the pancreas, are associated with increased proliferation, prevention of apoptosis, and enhanced differentiation in normal and disease states, but very little is known about the regulation of their expression. We hypothesized that Reg expression is influenced by microRNAs. Bioinformatic analysis predicted Reg1 to be a target of microRNA-7 (miR-7), which influences pancreatic β-cell function. To this end, we investigated the effects of miR-7 on Reg1 expression in pancreatic acinar and islet β-cells. High levels of Reg1 were noted by immunostaining and Western blotting in acinar cells in contrast to islet cells. A reciprocal expression pattern was observed for miR-7. Overexpression of miR-7 resulted in Reg1 mRNA suppression and reduction of secreted Reg1 protein. Conversely, miR-7 knockdown led to increases in Reg1. Targeting of Reg1 by miR-7 was confirmed via luciferase activity assays. In contrast, miR-7 did not directly repress the human ortholog of Reg1 REG1A as well as REG1B indicating species differences in the regulation of Reg expression. This is the first account of microRNA modulation of any Reg member warranting studies to fill gaps in our knowledge of Reg protein biology, particularly in disease contexts.

Expression of DEC2 enhances chemosensitivity by inhibiting STAT5A in gastric cancer

Gastric cancer (GC) is one of the most common cancers. Resistance to 5-fluorouracil (5-Fu)-based chemotherapy is a major cause of treatment failure followed by the poor prognosis of patients. In GC, it was reported that human differentiated embryonic chondrocyte-expressed gene 2 (DEC2), suppressed tumor proliferation and metastasis, but the effect of DEC2 on chemosensitivity of GC cells was unknown. In our study, we found that DEC2 can obviously increase the sensibility of GC cells to 5-Fu by promoting 5-Fu-induced apoptosis. DEC2 overexpression is significantly associated with decreased phosphorylation of STAT5A (P-STAT5A). More importantly, negative correlations between DEC2 with P-STAT5A expression were observed in tissue sections from GC patients. GC patients with low expression levels of DEC2 and high expression levels of P-STAT5A showed a poor prognosis. Furthermore, enhanced chemosensitivity mediated by DEC2 can be reversed by STAT5A which confer GC cells resistance to apoptosis induced by 5-Fu. Together, our results suggest that through inhibiting activation of STAT5A, DEC2 enhances 5-Fu-induced apoptosis and suppression of proliferation in GC cells. These findings will provide new insight for identifying potential targets that can be used to sensitize GC cells to chemotherapy.

Overexpression of IL-11 promotes premalignant gastric epithelial hyperplasia in isolation from germline gp130-JAK-STAT driver mutations

Expression of the cytokine IL-11 is elevated in human Helicobacter pylori infection and progressively increases with worsening gastric pathology. Additionally, IL-11 is required for tumor development in STAT3-dependent murine models of gastric cancer (GC) and, when administered acutely, causes resolving atrophic gastritis. However, it is unclear whether locally elevated IL-11 ligand expression can, in isolation from oncogenic gp130-JAK-STAT pathway mutations, initiate GC pathogenesis. Here we developed a transgenic mouse model of stomach-specific (keratin 19 promoter) IL-11 ligand overexpression. Keratin 19 promoter-IL-11 transgenic ( K19-IL11^Tg) mice showed specific IL-11 overexpression in gastric corpus and antrum but not elsewhere in the gastrointestinal tract or in other tissues. K19-IL11^Tg mice developed spontaneous premalignant disease of the gastric epithelium, progressing from atrophic gastritis to TFF2-positive metaplasia and severe epithelial hyperplasia, including adenoma-like lesions in a subset of older (1 yr old) animals. Although locally advanced, the hyperplastic lesions remained noninvasive. H. pylori infection in K19-IL11^Tg mice accelerated some aspects of the premalignant phenotype. Finally, K19-IL11^Tg mice had splenomegaly in association with elevated serum IL-11, with spleens showing an expanded myeloid compartment. Our results provide direct in vivo functional evidence that stomach-specific overexpression of IL-11, in isolation from germline gp130-JAK-STAT3 genetic drivers, is sufficient for premalignant progression. These findings have important functional implications for human GC, in which frequent IL-11 overexpression occurs in the reported absence of somatic mutations in gp130 signaling components. NEW & NOTEWORTHY We provide direct in vivo functional evidence that stomach-specific overexpression of the cytokine IL-11, in isolation from gp130-JAK-STAT3 pathway mutations, can trigger spontaneous atrophic gastritis progressing to locally advanced epithelial hyperplasia (but not dysplasia or carcinoma), which does not require, but may be accelerated by, concomitant Helicobacter pylori infection.

Preliminary study on the effect of nucleolin specific aptamer-miRNA let-7d chimera on Janus kinase-2 expression level and activity in gastric cancer (MKN-45) cells

Recently, much attention has been focused on the use of miRNAs in cancer treatment. The role of proto-oncogene Janus kinase-2 (JAK-2) in proliferation and survival of gastric cancer has been previously documented. The aim of this study was to evaluate the effect of a chimera consisted of nucleolin specific aptamer (NCL-Apt) and miRNA let-7d on JAK2 expression level and activity in gastric cancer cells. NCL-Apt-miRNA let-7d chimera was prepared by two methods. Gastric cancer (MKN-45) cell line and control cell line of human dermal fibroblast (HDF) were treated with the chimera and the changes in JAK2 expression and activity were determined using real-time PCR and ELISA techniques, respectively. In MKN-45 cells, the chimera caused significant decrease in JAK2 expression level and activity compared to the aptamer alone and miRNA mimic negative control. Nevertheless, transfected miRNA let-7d showed remarkable reduction in the expression level of JAK2 in comparison with control state in both MKN-45 and HDF, confirmed unspecific effect of let-7d on normal and cancerous cells. With regard to the synergic effect of this chimera on JAK2 activity, it might be viewed as a therapeutic candidate in gastric cancer. However, further studies are warranted to prove it.

Ganoderic acid A exerts antitumor activity against MDA-MB-231 human breast cancer cells by inhibiting the Janus kinase 2/signal transducer and activator of transcription 3 signaling pathway

Breast cancer is a common malignant tumor among females, with triple-negative breast cancer being an important type accounting for 15–20% of all breast cancer cases. Triple-negative breast cancer is one of the most aggressive types of cancer without standard adjuvant chemotherapy. Ganoderic acid A (GA-A) is one of the major bioactive Ganoderma triterpenoids isolated from Ganoderma, which are recognized for their preventative and therapeutic effects. In the present study, the antineoplastic effect of GA-A on human breast cancer was investigated and the pro-apoptotic function of Janus kinase (JAK)2 and signal transducer and activator of transcription (STAT)3 on the function of GA-A was revealed. GA-A treatment inhibited the invasion of MDA-MB-231 cells. In addition, GA-A exhibited significant antitumor activity by enhancing the apoptotic index and reactive oxygen species production. In the present study, GA-A was identified to directly inhibit JAK2 phosphorylation and STAT3 downstream activation. In addition, GA-A suppressed STAT3 target gene expression, including B cell lymphoma-extra-large and Myeloid cell leukemia 1, resulting in elevated levels of proteins associated with mitochondrial apoptosis in addition to inhibitors of cyclin-dependent kinase. GA-A, in combination with AG490, a JAK2/STAT3 inhibitor, further decreased MDA-MB-231 cell viability. In conclusion, GA-A treatment inhibited breast cancer cell viability via JAK2/STAT3 downregulation and may regulate associated targets to serve an anti-MDA-MB-231 role, including mitochondrial apoptosis and regulating the expression of cell-cycle-associated factors.

Inhibition of STAT3 in gastric cancer: role of pantoprazole as SHP-1 inducer

Background

We investigated the inhibitory effect of pantoprazole on signal transducer and activator of transcription 3 (STAT3) activity and invasiveness of gastric adenocarcinoma cells, and the role of SH2-containing protein tyrosine phosphatase 1 (SHP-1) in mediating role.

Methods

We used AGS and MKN-28 cells because of reduced SHP-1 and preserved p-STAT3 expression. Western blot, wound closure assay, Matrigel invasion assay and 3-D culture invasion assay were performed. Pharmacologic inhibitor of SHP-1 and siRNA were used for validation of the role of SHP-1.

Results

We observed that pantoprazole at 40, 80, and 160 μg/ml upregulated SHP-1 and downregulated p-STAT3 expression in a dose-dependent manner in AGS and MKN-28 cells. Furthermore, pantoprazole significantly downregulated mesenchymal markers (Snail1 and vimentin), upregulated epithelial marker (E-cadherin), and inhibited migration and invasion of AGS and MKN-28 cells. To validate the role of SHP-1 in inhibition of STAT3 activity by pantoprazole in gastric cancer cells, we performed pharmacologic inhibition (pervanadate) or knockdown of SHP-1 before pantoprazole treatment, which significantly attenuated the suppression of p-STAT3 and anti-migration and invasion effect by pantoprazole in AGS cells. In xenograft tumor model, tumor volume was significantly reduced by intraperitoneal injection of pantoprazole, with upregulation of SHP-1 and downregulation of p-STAT3, which were attenuated by concomitant injection of pervanadate.

Conclusion

Our data suggest that the inhibitory effect of pantoprazole on cellular migration and invasion might be through inducing SHP-1 in gastric cancer cells.

The Association Between AURKA Gene rs2273535 Polymorphism and Gastric Cancer Risk in a Chinese Population

The Aurora kinase A (AURKA) gene is frequently amplified and overexpressed in gastric cancer (GC). The overexpression of AURKA promotes inflammation and tumorigenesis in GC. We performed co-expression analysis to identify genes associated with AURKA and speculated its function through the COXPRESdb and STRING databases. We also conducted a hospital-based case-control study involving 385 GC cases and 470 controls in a Chinese population to evaluate the role of AURKA gene rs2273535 polymorphism in the risk of GC. Genotyping was performed using a custom-by-design 48-Plex single nucleotide polymorphism (SNP) Scan™ Kit. Co-expression analysis indicated that the overexpression of AURKA may be associated with poor prognosis of GC. In addition, TT genotypes of rs2273535 polymorphism increased the risk of GC by 72% compared to the AA genotypes. This significant correlation was also observed in the allelic and dominant models. The stratified analysis suggested that TT+AT genotypes showed positive correlation with the risk of GC among female, age <55 years group and non-smokers compared to AA genotypes. In conclusion, AURKA plays an important role in the development of GC. Larger studies with more diverse ethnic populations are needed to confirm these results.

Prognostic significance of microsatellite instability‑associated pathways and genes in gastric cancer

The aim of the present study was to reveal the potential molecular mechanisms of microsatellite instability (MSI) on the prognosis of gastric cancer (GC). The investigation was performed based on an RNAseq expression profiling dataset downloaded from The Cancer Genome Atlas, including 64 high‑level MSI (MSI‑H) GC samples, 44 low‑level MSI (MSI‑L) GC samples and 187 stable microsatellite (MSI‑S) GC samples. Differentially expressed genes (DEGs) were identified between the MSI‑H, MSI‑L and MSI‑S samples. Pathway enrichment analysis was performed for the identified DEGs and the pathway deviation scores of the significant enrichment pathways were calculated. A Multi‑Layer Perceptron (MLP) classifier, based on the different pathways associated with the MSI statuses was constructed for predicting the outcome of patients with GC, which was validated in another independent dataset. A total of 190 DEGs were selected between the MSI‑H, MSI‑L and MSI‑S samples. The MLP classifier was established based on the deviation scores of 10 significant pathways, among which antigen processing and presentation, and inflammatory bowel disease pathways were significantly enriched with HLA‑DRB5, HLA‑DMA, HLA‑DQA1 and HLA‑DRA; the measles, toxoplasmosis and herpes simplex infection pathways were significantly enriched with Janus kinase 2 (JAK2), caspase‑8 (CASP8) and Fas. The classifier performed well on an independent validation set with 100 GC samples. Taken together, the results indicated that MSI status may affect GC prognosis, partly through the antigen processing and presentation, inflammatory bowel disease, measles, toxoplasmosis and herpes simplex infection pathways. HLA‑DRB5, HLA‑DMA, HLA‑DQA1, HLA‑DRA, JAK2, CASP8 and Fas may be predictive factors for prognosis in GC.

pSTAT3 Levels Have Divergent Expression Patterns and Associations with Survival in Squamous Cell Carcinoma and Adenocarcinoma of the Oesophagus

Signal transducers and activator of transcription (STAT)-3 is activated in cancers, where it promotes growth, inflammation, angiogenesis, and inhibits apoptosis. Tissue microarrays were generated using tissues from 154 patients, with oesophageal adenocarcinoma (OAC) (n = 116) or squamous cell carcinoma (SCC) (n = 38) tumours. The tissues were stained for pSTAT3 and IL-6R using immunohistochemistry. The OE33 (OAC) and OE21 (SCC) cell lines were treated with the STAT3 inhibitor, STATTIC. The Univariate cox regression analysis revealed that a positive pSTAT3 in SCC was adversely associated with survival (Hazard ratio (HR) 6.382, 95% CI 1.266–32.184), while a protective effect was demonstrated with the higher pSTAT3 levels in OAC epithelium (HR 0.74, 95% CI 0.574–0.953). The IL-6R intensity levels were higher in the SCC tumours compared with the OAC tumours for the core and leading edge tumour tissue. The pSTAT3 levels correlated positively with the IL-6R levels in both the OAC and SCC. The treatment of OE21 and OE33 cells with the STAT3 inhibitor STATTIC in vitro resulted in decreased survival, proliferation, migration, and increased apoptosis. The pSTAT3 expression was associated with adverse survival in SCC, but not in the OAC patients. The inhibition of STAT3 in both of the tumour subtypes resulted in alterations in the survival, proliferation, migration, and apoptosis, suggesting a potential role for therapeutically targeting STAT3.

Arsenic trioxide attenuates STAT-3 activity and epithelial-mesenchymal transition through induction of SHP-1 in gastric cancer cells

BACKGROUND

We investigated the effect of arsenic trioxide (ATO) for inhibition of signal transducer and activator of transcription 3 (STAT3) and epithelial-mesenchymal transition (EMT) in gastric cancer cells, and the role of SH2 domain-containing phosphatase-1 (SHP-1) during this process.

METHODS

We used AGS cells, which showed minimal SHP-1 expression and constitutive STAT3 expression. After treatment of ATO, cellular migration and invasion were assessed by using wound closure assay, Matrigel invasion assay and 3-D culture invasion assay. To validate the role of SHP-1, pervanadate, a pharmacologic phosphatase inhibitor, and SHP-1 siRNA were used. Xenograft tumors were produced, and ATO or pervanadate were administered via intraperitoneal (IP) route.

RESULTS

Treatment of ATO 5 and 10 μM significantly decreased cellular migration and invasion in a dose-dependent manner. Western blot showed that ATO upregulated SHP-1 expression and downregulated STAT3 expression, and immunofluorescence showed upregulation with E-cadherin (epithelial marker) and downregulation of Snail1 (mesenchymal marker) expression by ATO treatment. Anti-migration and invasion effect and modulation of SHP-1/STAT3 axis by ATO were attenuated by pervanadate or SHP-1 siRNA. IP injection of ATO significantly decreased the xenograft tumor volume and upregulated SHP-1 expression, which were attenuated by co-IP injection of pervanadate.

CONCLUSION

Our data suggest that ATO inhibits STAT3 activity and EMT process by upregulation of SHP-1 in gastric cancer cells.

Mitochondrial GRIM-19 as a potential therapeutic target for STAT3-dependent carcinogenesis of gastric cancer

Aberrant STAT3 activation occurs in most human gastric cancers (GCs) and contributes to the malignant progression of GC, but mechanism(s) underlying aberrant STAT3 remain largely unknown. Here we demonstrated that the gene associated with retinoid interferon-induced mortality 19 (GRIM-19) was severely depressed or lost in GC and chronic atrophic gastritis (CAG) tissues and its loss contributed to GC tumorigenesis partly by activating STAT3 signaling. In primary human GC tissues, GRIM-19 was frequently depressed or lost and this loss correlated with advanced clinical stage, lymph node metastasis, H. pylori infection and poor overall survival of GC patients. In CAG tissues, GRIM-19 was progressively decreased along with its malignant transformation. Functionally, we indentified an oncogenic role of GRIM-19 loss in promoting GC tumorigenesis. Ectopic GRIM-19 expression suppressed GC tumor formation in vitro and in vivo by inducing cell cycle arrest and apoptosis. Moreover, we revealed that GRIM-19 inhibited STAT3 transcriptional activation and its downstream targets by reducing STAT3 nuclear distribution. Conversely, knockdown of GRIM-19 induced aberrant STAT3 activation and accelerated GC cell growth in vitro and in vivo, and this could be partly attenuated by the blockage of STAT3 activation. In addition, we observed subcellular redistributions of GRIM-19 characterized by peri-nuclear aggregates, non-mitochondria cytoplasmic distribution and nuclear invasion, which should be responsible for reduced STAT3 nuclear distribution. Our studies suggest that mitochondrial GRIM-19 could not only serve as an valuable prognostic biomarker for GC development, but also as a potential therapeutic target for STAT3-dependent carcinogenesis of GC.

Associations of potentially functional variants in IL-6, JAKs and STAT3 with gastric cancer risk in an eastern Chinese population

The interleukin-6 (IL-6)/JAK/STAT3 signaling pathway plays a central role in inflammation-mediated cancers, including gastric cancer (GCa). We evaluated associations between 10 potentially functional single nucleotide polymorphisms (SNPs) of four essential genes in the pathway and GCa risk in a study of 1,125 GCa cases and 1,221 cancer-free controls. We found that a significant higher GCa risk was associated with IL-6 rs2069837G variant genotypes [adjusted odds ratios (OR) = 1.33; 95% confidence interval (CI) = 1.12-1.59 for AG + GG vs. AA)] and JAK1 rs2230587A variant genotypes (adjusted OR = 1.20; 95% CI = 1.02-1.43 for GA + AA vs. GG). We also found that a significant decreased GCa risk was associated with STAT3 rs1053004G variant genotypes (adjusted OR = 0.84; 95% CI = 0.71-0.99 for AG + GG vs. AA). The combined analysis of IL-6 rs2069837G and JAK1 rs2230587A variant risk genotypes revealed that individuals with one-or-two risk genotypes exhibited an increased risk for GCa (adjusted OR = 1.34; 95% CI = 1.13-1.59). Genotypes and mRNA expression correlation analysis using the data from the HapMap 3 database provided further support for the observed risk associations. Larger studies are warranted to validate these findings.

A novel small molecule STAT3 inhibitor, LY5, inhibits cell viability, colony formation, and migration of colon and liver cancer cells

Signal Transducer and Activator of Transcription 3 (STAT3) is persistently activated in human liver and colon cancer cells and is required for cancer cell viability, survival and migration. Therefore, inhibition of STAT3 signaling may be a viable therapeutic approach for these two cancers. We recently designed a non-peptide small molecule STAT3 inhibitor, LY5, using in silico site-directed Fragment-based drug design (FBDD). The inhibitory effect on STAT3 phosphorylation, cell viability, migration and colony forming ability by LY5 were examined in human liver and colon cancer cells. We demonstrated that LY5 inhibited constitutive Interleukin-6 (IL-6)-induced STAT3 phosphorylation, STAT3 nuclear translocation, decreased STAT3 downstream targeted gene expression and induced apoptosis in liver and colon cancer cells. LY5 had little effect on STAT1 phosphorylation mediated by IFN-γ. Inhibition of persistent STAT3 phosphorylation by LY5 also inhibited colony formation, cell migration, and decreased the viability of liver cancer and colon cancer cells. Furthermore, LY5 inhibited STAT3 phosphorylation and suppressed colon tumor growth in a mouse model in vivo. Our results suggest that LY5 is a potent STAT3 inhibitor and may be a potential drug candidate for liver and colon cancer therapy.

Kinome and Transcriptome Profiling Reveal Broad and Distinct Activities of Erlotinib, Sunitinib, and Sorafenib in the Mouse Heart and Suggest Cardiotoxicity From Combined Signal Transducer and Activator of Transcription and Epidermal Growth Factor Receptor Inhibition

BACKGROUND

Most novel cancer therapeutics target kinases that are essential to tumor survival. Some of these kinase inhibitors are associated with cardiotoxicity, whereas others appear to be cardiosafe. The basis for this distinction is unclear, as are the molecular effects of kinase inhibitors in the heart.

METHODS AND RESULTS

We administered clinically relevant doses of sorafenib, sunitinib (cardiotoxic multitargeted kinase inhibitors), or erlotinib (a cardiosafe epidermal growth factor receptor inhibitor) to mice daily for 2 weeks. We then compared the effects of these 3 kinase inhibitors on the cardiac transcriptome using RNAseq and the cardiac kinome using multiplexed inhibitor beads coupled with mass spectrometry. We found unexpectedly broad molecular effects of all 3 kinase inhibitors, suggesting that target kinase selectivity does not define either the molecular response or the potential for cardiotoxicity. Using in vivo drug administration and primary cardiomyocyte culture, we also show that the cardiosafety of erlotinib treatment may result from upregulation of the cardioprotective signal transducer and activator of transcription 3 pathway, as co-treatment with erlotinib and a signal transducer and activator of transcription inhibitor decreases cardiac contractile function and cardiomyocyte fatty acid oxidation.

CONCLUSIONS

Collectively our findings indicate that preclinical kinome and transcriptome profiling may predict the cardiotoxicity of novel kinase inhibitors, and suggest caution for the proposed therapeutic strategy of combined signal transducer and activator of transcription/epidermal growth factor receptor inhibition for cancer treatment.

MicroRNA-216a inhibits the metastasis of gastric cancer cells by targeting JAK2/STAT3-mediated EMT process

MicroRNAs (miRNAs), a group of small, non-protein coding, endogenous RNAs, play critical roles in the tumorigenesis and progression of human cancer. miR-216a has recently been reported to play an oncogenic role in human cancer. While, the expression of miR-216a, its biological function and underlying molecular mechanisms in gastric cancer (GC) are largely unknown. In this study, we revealed that miR-216a was underexpressed in GC tissues compared to matched noncancerous tissues. Decreased levels of miR-216a were confirmed in GC cell lines compared with a normal gastric epithelium cell line. miR-216a underexpression was associated with malignant prognostic features including lymph node metastasis, venous infiltration, invasive depth and advanced TNM stage. GC patients with low miR-216a level showed an obvious shorter overall survival. miR-216a overexpression restrained migration and invasion of MGC-803 cells, while its knockdown exerted opposite effects on metastatic behaviors of SGC-7901 cells. In vivo experiments found that miR-216a restoration reduced metastatic nodes of GC cells in nude mice liver. miR-216a notably suppressed epithelial-mesenchymal transition (EMT) of GC cells. Janus kinase 2 (JAK2) was recognized as a direct target and downstream mediator of miR-216a in GC cells. Interestingly, JAK2/signal transducer and activator of transcription 3 (STAT3) pathway was prominently inactivated by miR-216a and probably mediated the role of miR-216a in the regulation of migration, invasion and EMT process of GC cells. In conclusion, these data suggest that miR-216a functions as a tumor suppressive miRNA in the development of GC possibly by targeting JAK2/STAT3-mediated EMT.

The conundrum of the Epstein-Barr virus-associated gastric carcinoma in the Americas

Epstein-Barr virus-associated gastric carcinoma shows a higher prevalence in the Americas than Asia. We summarize all studies of Epstein Barr virus-associated gastric carcinoma in the Americas, focusing on host characteristics, environmental associations and phylogeographic diversity of Epstein-Barr virus strains. In the Americas, the prevalence of Epstein Barr virus-associated gastric carcinoma is 11.4%, more frequent in males and portray predominantly diffuse-type histology. EBERs, EBNAs, BARTs and LMP are the highest expressed genes; their variations in healthy individuals may explain the phylogeographic diversity of Epstein-Barr virus across the region. Gastric cancer cases harbor exclusively the western genotype (subtype D and kept Xho I site), suggesting a disrupted co-evolution between the pathogen and its host. Epstein-Barr virus-associated gastric carcinoma molecular subtype cases from The Cancer Genome Atlas display PIK3CA gene mutations, amplification of JAK2, PD-L1 and PD-L2 and CpG island methylator phenotype, leading to more extensive methylation of host and viral genomes than any other subtypes from the study. Environmental conditions include negative- and positive- associations with being firstborn child and smoking, respectively. A marginal association with H. pylori has also been reported. Lymphoepithelioma-like carcinoma is associated with Epstein Barr virus in 80%-86% of cases, most of which have been included as part of Epstein Barr virus-associated gastric carcinoma series (prevalence 1.1%-7.6%). Whether these cases represent a variant of Epstein-Barr virus-associated gastric carcinoma is discussed. We propose novel research strategies to solve the conundrum of the high prevalence of Epstein-Barr virus-associated gastric carcinoma in the Americas.

STAT3 inhibition by WP1066 suppresses the growth and invasiveness of bladder cancer cells

Signal transducer and activator of transcription 3 (STAT3) regulates the expression of genes mediating cell survival, proliferation and angiogenesis and is aberrantly activated in various types of malignancies, including bladder cancer. We examined whether it could be a novel therapeutic target for bladder cancer using the STAT3 inhibitor WP1066. In T24 and UMUC-3 bladder cancer cells, 5 µM WP1066 prevented the phosphorylation of STAT3 and 2.5 µM WP1066 decreased cell survival and proliferation significantly (P<0.01). WP1066 also induced apoptosis accompanied by the suppression of the expression of Bcl-2 and Bcl-xL in T24 cells. Moreover, the covered area in a wound and the number of cells invading through a Matrigel chamber decreased significantly (P<0.01) when cells were treated with WP1066. The activities of MMP-2 and MMP-9 were also decreased by treatment with 10 µM WP1066. Our results revealed that using WP1066 to inhibit the STAT3 signaling pathway suppressed the viability and invasiveness of bladder cancer cells effectively and could be a novel therapeutic strategy against bladder cancer.

Knockdown of long non-coding RNA HOXD-AS1 inhibits gastric cancer cell growth via inactivating the JAK2/STAT3 pathway

Long non-coding RNA HOXD-AS1 (HOXD cluster antisense RNA 1) has been demonstrated to be closely associated with the progression of several tumors. However, the biological function of HOXD-AS1 and the underlying molecular mechanism in gastric cancer are still unclear. The expression of HOXD-AS1 in gastric cancer cell lines was evaluated by quantitative real-time polymerase chain reaction. The association of HOXD-AS1 expression and clinical parameters was statistically analyzed by chi-square test. Cell viability, colony formation capacity, and phosphorylation of Janus kinase 2 and signal transducer and activator of transcription 3 in treated SGC-7901 and BGC-823 cells were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, colony formation assay, and western blot analysis, respectively. The results indicated that HOXD-AS1 was significantly upregulated in gastric cancer cells and clinically involved in tumor size, invasion depth, tumor-node-metastasis stages, regional lymph nodes, lymphatic metastasis, as well as distant metastasis. HOXD-AS1 knockdown dramatically inhibited gastric cancer cell proliferation, colony formation capacity, and phosphorylation of Janus kinase 2 and signal transducer and activator of transcription 3 in vitro. In addition, HOXD-AS1 overexpression significantly promoted gastric cancer cell proliferation and colony formation capacity, whereas both Janus kinase small interfering RNAs and Janus kinase 2 inhibitor AG490 overturned these effects. Furthermore, xenograft assays confirmed the biological function of HOXD-AS1 in vivo. Taken together, our data elucidate that knockdown of HOXD-AS1 dramatically suppresses gastric cancer cell growth by inactivating the Janus kinase 2/signal transducer and activator of transcription 3 pathway in vitro and in vivo, contributing to a better understanding of gastric cancer pathogenesis and providing a possible theoretical foundation for long non-coding RNA-directed diagnosis and therapy against this disease.

Characterization of the aminopyridine derivative KRC-180 as a JAK2 inhibitor

Janus kinase 2 (JAK2) is a non-receptor tyrosine kinase that regulates the signal transducer and activator of transcription (STAT) signaling pathway. Deregulation of JAK2 signaling has previously been observed in hematologic malignancies, including erythroleukemia. In the present study, an aminopyridine derivative compound, KRC-180, exhibited direct inhibition of the JAK2 protein at the catalytic site, as demonstrated using in vitro kinase activity assays and docking analyses. In addition, KRC-180 reduced the phosphorylation of STAT3 and STAT5, downstream signaling molecules of JAK2. The growth of HEL92.1.7 erythroleukemia cells harboring a constitutively activated form of JAK2 was suppressed by KRC-180 treatment; KRC-180 induced apoptotic cell death and cell cycle arrest. The results of the present study indicate that KRC-180 is a JAK2 inhibitor with anti-leukemic properties.