STAT1 Is Required for Decreasing Accumulation of Granulocytic Cells via IL-17 during Initial Steps of Colitis-Associated Cancer

The role of innate immune cells in the colorectal cancer tumor microenvironment and advances in anti-tumor therapy research

Innate immune cells in the colorectal cancer microenvironment mainly include macrophages, neutrophils, natural killer cells, dendritic cells and bone marrow-derived suppressor cells. They play a pivotal role in tumor initiation and progression through the secretion of diverse cytokines, chemokines, and other factors that govern these processes. Colorectal cancer is a common malignancy of the gastrointestinal tract, and understanding the role of innate immune cells in the microenvironment of CRC may help to improve therapeutic approaches to CRC and increase the good prognosis. In this review, we comprehensively explore the pivotal role of innate immune cells in the initiation and progression of colorectal cancer (CRC), alongside an extensive evaluation of the current landscape of innate immune cell-based immunotherapies, thereby offering valuable insights for future research strategies and clinical trials.

Helper T cell subsets: Development, function and clinical role in hypersensitivity reactions in the modern perspective

Helper T cells are traditionally classified into T helper 1 (TH1) and T helper 2 (TH2). The more recent discoveries of T helper 17 (TH17), follicular helper T cells (TFH) and regulatory T cells (Treg) enhanced our understanding on the mechanisms of immune function and hypersensitivity reactions, which shaped the modern perspective on the function and role of these different subsets of helper T cells in hypersensitivity reactions. Each subset of helper T cells has characteristic roles in different types of hypersensitivity reactions, hence giving rise to the respective characteristic clinical manifestations. The roles of helper T cells in allergic contact dermatitis (TH1-mediated), drug rash with eosinophilia and systemic symptoms (DRESS) syndrome (TH2-mediated), and acute generalised exanthematous pustulosis (AGEP) (TH17-mediated) are summarised in this article, demonstrating the correlation between the type of helper T cell involved and the clinical features. TFH plays crucial roles in antibody class-switch recombination; they may be implicated in antibody-mediated hypersensitivity reactions, but further research is warranted to delineate their exact pathogenic roles. The helper T cell subsets and their specific cytokine profiles implicated in different hypersensitivity reactions could be potential treatment targets by biologics, but more clinical trials are warranted to establish their clinical effectiveness.

STAT1 Employs Myeloid Cell-Extrinsic Mechanisms to Regulate the Neutrophil Response and Provide Protection against Invasive Klebsiella pneumoniae Lung Infection

Klebsiella pneumoniae (KP) is an extracellular Gram-negative bacterium that causes infections in the lower respiratory and urinary tracts and the bloodstream. STAT1 is a master transcription factor that acts to maintain T cell quiescence under homeostatic conditions. Although STAT1 helps defend against systemic spread of acute KP intrapulmonary infection, whether STAT1 regulation of T cell homeostasis impacts pulmonary host defense during acute bacterial infection and injury is less clear. Using a clinical KP respiratory isolate and a pneumonia mouse model, we found that STAT1 deficiency led to an early neutrophil-dominant transcriptional profile and neutrophil recruitment in the lung preceding widespread bacterial dissemination and lung injury development. Yet, myeloid cell STAT1 was dispensable for control of KP proliferation and dissemination, because myeloid cell-specific STAT1-deficient (LysMCre/WT;Stat1fl/fl) mice showed bacterial burden in the lung, liver, and kidney similar to that of their wild-type littermates. Surprisingly, IL-17-producing CD4+ T cells infiltrated Stat1-/- murine lungs early during KP infection. The increase in Th17 cells in the lung was not due to preexisting immunity against KP and was consistent with circulating rather than tissue-resident CD4+ T cells. However, blocking global IL-17 signaling with anti-IL-17RC administration led to increased proliferation and dissemination of KP, suggesting that IL-17 provided by other innate immune cells is essential in defense against KP. Contrastingly, depletion of CD4+ T cells reduced Stat1-/- murine lung bacterial burden, indicating that early CD4+ T cell activation in the setting of global STAT1 deficiency is pathogenic. Altogether, our findings suggest that STAT1 employs myeloid cell-extrinsic mechanisms to regulate neutrophil responses and provides protection against invasive KP by restricting nonspecific CD4+ T cell activation and immunopathology in the lung.

Colitis-associated carcinogenesis: crosstalk between tumors, immune cells and gut microbiota

Colorectal cancer (CRC) is the third most common cancer worldwide. One of the main causes of colorectal cancer is inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn's disease (CD). Intestinal epithelial cells (IECs), intestinal mesenchymal cells (IMCs), immune cells, and gut microbiota construct the main body of the colon and maintain colon homeostasis. In the development of colitis and colitis-associated carcinogenesis, the damage, disorder or excessive recruitment of different cells such as IECs, IMCs, immune cells and intestinal microbiota play different roles during these processes. This review aims to discuss the various roles of different cells and the crosstalk of these cells in transforming intestinal inflammation to cancer, which provides new therapeutic methods for chemotherapy, targeted therapy, immunotherapy and microbial therapy.

Qingyihuaji Formula promotes apoptosis and autophagy through inhibition of MAPK/ERK and PI3K/Akt/mTOR signaling pathway on pancreatic cancer in vivo and in vitro

ETHNOPHARMACOLOGICAL RELEVANCE

Qingyihuaji Formula (QYHJ), a widely used traditional Chinese medicine (TCM), has been used to treat patients with cancer in China. However, the effect and mechanism of QYHJ on pancreatic ductal adenocarcinoma (PDAC) remains unclear.

AIM OF THE STUDY

This study aimed to explore the roles and evaluate the possible underlying molecular mechanisms of QYHJ and its core component in PDAC using label-free quantitative proteomics in conjunction with network pharmacology-based analysis.

MATERIALS AND METHODS

By screening differentially expressed proteins (DEPs) in proteomics and QYHJ-predicted gene sets, we identified QYHJ-related PDAC targets annotated with bioinformatic analysis. A subcutaneous tumor model was established to assess the role of QYHJ in vivo. The effects of quercetin (Que), a core component of QYHJ, on cell proliferation, migration, invasion, apoptosis, and autophagy in SW1990 and PANC-1 cells were investigated in vitro. Immunohistochemistry, western blotting, mRFP-GFP-LC3 adenovirus, and kinase analysis were used to determine the underlying mechanisms.

RESULTS

Bioinformatics analysis revealed that 41 QYHJ-related PDAC targets were closely related to the cellular response to nitrogen compounds, positive regulation of cell death, regulation of epithelial cell apoptotic processes, and chemokine signaling pathways. CASP3, SRC, STAT1, PTPN11, PKM, and PAK1 with high expression were identified as hub DEPs in the PPI network, and these DEPs were associated with poor overall survival and STAT 1, MAPK/ERK, and PI3K/Akt/mTOR signaling pathways in PDAC patients. QYHJ significantly promoted tumor death in nude mice. Moreover, quercetin inhibited the proliferation, migration, and invasion of PDAC cells. Additionally, Que induced apoptosis and autophagy in PDAC cells. Mechanistically, QYHJ and Que significantly activated STAT 1 and remarkably inhibited the MAPK/ERK and PI3K/Akt/mTOR signaling pathways in vivo and in vitro, respectively. Importantly, ERK1/2 inactivation contributes to que-induced apoptosis in SW1990 and PANC-1 cells.

CONCLUSIONS

These results suggest that QYHJ and Que are promising anti-PDAC avenues that benefit from their multiform mechanisms.

Mexican Colorectal Cancer Research Consortium (MEX-CCRC): Etiology, Diagnosis/Prognosis, and Innovative Therapies

In 2013, recognizing that Colorectal Cancer (CRC) is the second leading cause of death by cancer worldwide and that it was a neglected disease increasing rapidly in Mexico, the community of researchers at the Biomedicine Research Unit of the Facultad de Estudios Superiores Iztacala from the Universidad Nacional Autónoma de México (UNAM) established an intramural consortium that involves a multidisciplinary group of researchers, technicians, and postgraduate students to contribute to the understanding of this pathology in Mexico. This article is about the work developed by the Mexican Colorectal Cancer Research Consortium (MEX-CCRC): how the Consortium was created, its members, and its short- and long-term goals. Moreover, it is a narrative of the accomplishments of this project. Finally, we reflect on possible strategies against CRC in Mexico and contrast all the data presented with another international strategy to prevent and treat CRC. We believe that the Consortium's characteristics must be maintained to initiate a national strategy, and the reported data could be useful to establish future collaborations with other countries in Latin America and the world.

IL-17A promotes Helicobacter pylori-induced gastric carcinogenesis via interactions with IL-17RC

BACKGROUND

Gastric cancer (GC) is a common malignancy worldwide, with a major attribution to Helicobacter pylori. Interleukin (IL)-17A has been reported to be up-regulated in serum and tumor of GC patients, but the precise mechanisms underlying its involvement in gastric tumorigenesis are yet to be established. Here, we investigated the roles of IL-17A in the pathogenesis of H. pylori-induced GC.

METHODS

GC was induced in IL-17A knockout (KO) and wild-type (WT) mice via N-methyl-N-nitrosourea (MNU) treatment and H. pylori infection. At 50 weeks after treatment, gastric tissues were examined by histopathology, immunohistochemistry, and immunoblot analyses. In vitro experiments on the human GC cell lines were additionally performed to elucidate the underlying mechanisms.

RESULTS

Deletion of IL-17A suppressed MNU and H. pylori-induced gastric tumor development accompanied by a decrease in gastric epithelial cell growth, oxidative stress, and expression of gastric epithelial stem cells markers. In AGS cells, recombinant human IL-17A (rhIL-17A) inhibited apoptosis and G1/S phase transition arrest while promoting reactive oxygen species production, sphere formation ability of cancer stem cells (CSC), and expression of stemness-related genes. In addition, rhIL-17A induced expression of IL-17RC, leading to NF-κB activation and increased NADPH oxidase 1 (NOX1) levels. Inhibition of NOX1 with GKT136901 attenuated rhIL-17A-mediated elevation of GC cell growth, ROS generation, and CSC stemness. Clinically, IL-17RC expressions were significantly upregulated in human GC compared with normal gastric tissues.

CONCLUSION

Our results suggest that IL-17A promotes gastric carcinogenesis, in part, by regulating IL-17RC/NF-κB/NOX1 pathway, supporting its potential as a target in human GC therapy.

Perspectives of herbs and their natural compounds, and herb formulas on treating diverse diseases through regulating complicated JAK/STAT signaling

JAK/STAT signaling pathways are closely associated with multiple biological processes involved in cell proliferation, apoptosis, inflammation, differentiation, immune response, and epigenetics. Abnormal activation of the STAT pathway can contribute to disease progressions under various conditions. Moreover, tofacitinib and baricitinib as the JAK/STAT inhibitors have been recently approved by the FDA for rheumatology disease treatment. Therefore, influences on the STAT signaling pathway have potential and perspective approaches for diverse diseases. Chinese herbs in traditional Chinese medicine (TCM), which are widespread throughout China, are the gold resources of China and have been extensively used for treating multiple diseases for thousands of years. However, Chinese herbs and herb formulas are characterized by complicated components, resulting in various targets and pathways in treating diseases, which limits their approval and applications. With the development of chemistry and pharmacology, active ingredients of TCM and herbs and underlying mechanisms have been further identified and confirmed by pharmacists and chemists, which improved, to some extent, awkward limitations, approval, and applications regarding TCM and herbs. In this review, we summarized various herbs, herb formulas, natural compounds, and phytochemicals isolated from herbs that have the potential for regulating multiple biological processes via modulation of the JAK/STAT signaling pathway based on the published work. Our study will provide support for revealing TCM, their active compounds that treat diseases, and the underlying mechanism, further improving the rapid spread of TCM to the world.

Tofacitinib enhances IGF1 via inhibiting STAT6 transcriptionally activated-miR-425-5p to ameliorate inflammation in RA-FLS

Rheumatoid arthritis (RA) is a systemic autoimmune disease, which has been reported closely associated with the dysfunction of the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway. This study aims to explore the potential therapeutic effect of Tofacitinib, a putative JAK/STAT inhibitor, in RA. Tofacitinib suppressed proliferation and accelerated apoptosis of rheumatoid arthritis synovial fibroblasts (RA-FLS) as confirmed by CCK-8, EdU and Western blot assays. Tofacitinib significantly inhibited expression of pro-inflammatory factors including tumor necrosis factor-α (TNF-α), vascular endothelial growth factor A, matrix metalloproteinase 1, matrix metalloproteinase 3, interleukin-6 and interferon gamma in RA-FLS cells. mechanistically, tofacitinib decreased signal transducer and activator of transcription 6 (STAT6), which transcriptionally activates miR-425-5p, and thus increased insulin like growth factor 1 (IGF1) expression, a target of miR-425-5p in RA-FLS. Overexpression of STAT6 restored the expression of pro-inflammatory factors and proliferation inhibited by Tofacitinib in RA-FLS. Overall, Tofacitinib exerted inhibitory effect on proliferation and inflammation of RA-FLS through modulating STAT6/miR-425-5p/IGF1 signal axis. These findings shed light on the novel strategies for improving RA.

Drug Resistance in Colorectal Cancer: From Mechanism to Clinic

Colorectal cancer (CRC) is one of the leading causes of death worldwide. The 5-year survival rate is 90% for patients with early CRC, 70% for patients with locally advanced CRC, and 15% for patients with metastatic CRC (mCRC). In fact, most CRC patients are at an advanced stage at the time of diagnosis. Although chemotherapy, molecularly targeted therapy and immunotherapy have significantly improved patient survival, some patients are initially insensitive to these drugs or initially sensitive but quickly become insensitive, and the emergence of such primary and secondary drug resistance is a significant clinical challenge. The most direct cause of resistance is the aberrant anti-tumor drug metabolism, transportation or target. With more in-depth research, it is found that cell death pathways, carcinogenic signals, compensation feedback loop signal pathways and tumor immune microenvironment also play essential roles in the drug resistance mechanism. Here, we assess the current major mechanisms of CRC resistance and describe potential therapeutic interventions.