Role of Regenerating Islet-Derived Protein 3A in Gastrointestinal Cancer

Increased expression of REG3A promotes tumorigenic behavior in triple negative breast cancer cells

BACKGROUND

Identifying new targets in triple negative breast cancer (TNBC) remains critical. REG3A (regenerating islet-derived protein 3 A), a calcium-dependent lectin protein, was thoroughly investigated for its expression and functions in breast cancer.

METHODS

Bioinformatics and local tissue analyses were employed to identify REG3A expression in breast cancer. Genetic techniques were employed to modify REG3A expression, and the resulting effects on the behaviors of breast cancer cells were examined. Subcutaneous xenograft models were established to investigate the involvement of REG3A in the in vivo growth of breast cancer cells.

RESULTS

Analysis of the TCGA database uncovered increased REG3A levels in human breast cancer tissues. Additionally, REG3A mRNA and protein levels were elevated in TNBC tissues of locally treated patients, contrasting with low expression in adjacent normal tissues. In primary human TNBC cells REG3A shRNA notably hindered cell proliferation, migration, and invasion while triggering caspase-mediated apoptosis. Similarly, employing CRISPR-sgRNA for REG3A knockout showed significant anti-TNBC cell activity. Conversely, REG3A overexpression bolstered cell proliferation and migration. REG3A proved crucial for activating the Akt-mTOR cascade, as evidenced by decreased Akt-S6K1 phosphorylation upon REG3A silencing or knockout, which was reversed by REG3A overexpression. A constitutively active mutant S473D Akt1 (caAkt1) restored Akt-mTOR activation and counteracted the proliferation inhibition and apoptosis induced by REG3A knockdown in breast cancer cells. Crucially, REG3A played a key role in maintaining mTOR complex integrity. Bioinformatics identified zinc finger protein 680 (ZNF680) as a potential REG3A transcription factor. Knocking down or knocking out ZNF680 reduced REG3A expression, while its overexpression increased it in primary breast cancer cells. Additionally, enhanced binding between ZNF680 protein and the REG3A promoter was observed in breast cancer tissues and cells. In vivo, REG3A shRNA significantly inhibited primary TNBC cell xenograft growth. In REG3A-silenced xenograft tissues, reduced REG3A levels, Akt-mTOR inhibition, and activated apoptosis were evident.

CONCLUSION

ZNF680-caused REG3A overexpression drives tumorigenesis in breast cancer possibly by stimulating Akt-mTOR activation, emerging as a promising and innovative cancer target.

Unveiling the role of interleukin-6 in pancreatic cancer occurrence and progression

Pancreatic cancer is difficult to diagnose early and progresses rapidly. Researchers have found that a cytokine called Interleukin-6 (IL-6) is involved in the entire course of pancreatic cancer, promoting its occurrence and development. From the earliest stages of pancreatic intraepithelial neoplasia to the invasion and metastasis of pancreatic cancer cells and the appearance of tumor cachexia, IL-6 drives oncogenic signal transduction pathways and immune escape that accelerate disease progression. IL-6 is considered a biomarker for pancreatic cancer diagnosis and prognosis, as well as a potential target for treatment. IL-6 antibodies are currently being explored as a hot topic in oncology. This article aims to systematically explain how IL-6 induces the deterioration of normal pancreatic cells, with the goal of finding a breakthrough in pancreatic cancer diagnosis and treatment.

Lipid Metabolism-Related Gene Markers Used for Prediction Prognosis, Immune Microenvironment, and Tumor Stage of Pancreatic Cancer

Recently, more and more evidence shows that lipid metabolism disorder has been observed in tumor, which impacts tumor cell proliferation, survival, invasion, metastasis, and response to the tumor microenvironment (TME) and tumor treatment. However, hitherto there has not been sufficient research to demonstrate the role of lipid metabolism in pancreatic cancer. This study contrives to get an insight into the relationship between the characteristics of lipid metabolism and pancreatic cancer. We collected samples of patients with pancreatic cancer from the Gene Expression Omnibus (GEO), the Therapeutically Applicable Research to Generate Effective Treatments (TARGET), and the International Cancer Genome Consortium (ICGC) databases. Firstly, we implemented univariate regression analysis to get prognosis-related lipid metabolism genes screened and a construction of protein-protein interaction (PPI) network ensued. Then, contingent on our screening results, we explored the molecular subtypes mediated by lipid metabolism-related genes and the correlated TME cell infiltration. Additionally, we studied the disparately expressed genes among disparate lipid metabolism subtypes and established a scoring model of lipid metabolism-related characteristics using the least absolute shrinkage and selection operator (LASSO) regression analysis. At last, we explored the relationship between the scoring model and disease prognosis, tumor stage, tumor microenvironment, and immunotherapy. Two subtypes, C1 and C2, were identified, and lipid metabolism-related genes were studied. The result indicated that the patients with subtype C2 have a significantly lower survival rate than that of the patients with subtype C1, and we found difference in abundance of different immune-infiltrating cells. The gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses revealed the association of these differentially expressed genes with functions and pathways related to lipid metabolism. Finally, we established a scoring model of lipid metabolism-related characteristics based on the disparately expressed genes. The results show that our scoring model have a substantial effect on forecasting the prognosis of patients with pancreatic cancer. The lipid metabolism model is an important biomarker of pancreatic cancer. Using the model, the relationship between disease prognosis, molecular subtypes, TME cell infiltration characteristics, and immunotherapy in pancreatic cancer patients could be explored.

REG3A overexpression functions as a negative predictive and prognostic biomarker in rectal cancer patients receiving CCRT

BACKGROUND

Concurrent chemoradiotherapy (CCRT) is suggested before resection surgery in the control of rectal cancer. Unfortunately, treatment outcomes are widely variable and highly patient-specific. Notably, rectal cancer patients with distant metastasis generally have a much lower survival rate. Accordingly, a better understanding of the genetic background of patient cohorts can aid in predicting CCRT efficacy and clinical outcomes for rectal cancer before distant metastasis.

METHODS

A published transcriptome dataset (GSE35452) (n=46) was utilized to distinguish prospective genes concerning the response to CCRT. We recruited 172 rectal cancer patients, and the samples were collected during surgical resection after CCRT. Immunohistochemical (IHC) staining was performed to evaluate the expression level of regenerating family member 3 alpha (REG3A). Pearson's chi-squared test appraised the relevance of REG3A protein expression to clinicopathological parameters. The Kaplan-Meier method was utilized to generate survival curves, and the log-rank test was performed to compare the survival distributions between two given groups.

RESULTS

Employing a transcriptome dataset (GSE35452) and focusing on the inflammatory response (GO: 0006954), we recognized that REG3A is the most significantly upregulated gene among CCRT nonresponders (log2 ratio=1.2472, p=0.0079). Following IHC validation, high immunoexpression of REG3A was considerably linked to advanced post-CCRT tumor status (p<0.001), post-CCRT lymph node metastasis (p=0.042), vascular invasion (p=0.028), and low-grade tumor regression (p=0.009). In the multivariate analysis, high immunoexpression of REG3A was independently correlated with poor disease-specific survival (DSS) (p=0.004) and metastasis-free survival (MeFS) (p=0.045). The results of the bioinformatic analysis also supported the idea that REG3A overexpression is implicated in rectal carcinogenesis.

CONCLUSION

In the current study, we demonstrated that REG3A overexpression is correlated with poor CCRT effectiveness and inferior patient survival in rectal cancer. The predictive and prognostic utility of REG3A expression may direct patient stratification and decision-making more accurately for those patients.

Tumor-suppressive effect of Reg3A in COAD is mediated by T cell activation in nude mice

Regenerating family protein 3 A (Reg3A) is highly expressed in a variety of organs and inflammatory tissues, and is closely related to tumorigenesis and cancer progression. However, clinical statistics show that high expression of Reg3A is associated with better prognosis in colorectal cancer (CRC) patients, suggesting a tumor-suppressive effect. The precise action and underlying mechanism of Reg3A in CRC remain controversial. The present study sought to investigate the relationship among Reg3A expression, CRC development, and immune cell alteration in patients using the TCGA, GEPIA, PrognoScan, TIMER and TISIDB databases. Reg3A-overexpressing LoVo cell line (LoVo-Reg3A), a representative of colon adenocarcinoma (COAD), was constructed and the action of Reg3A was assessed in a xenograft nude mouse model. Our bioinformatical analyses revealed that Reg3A upregulation is highly associated with CRC, along with increased frequency of immune cell infiltration. In the xenograft nude mice, Reg3A overexpression offered a tumor-suppressive effect by inhibiting cell proliferation and promoting apoptosis. The result of RNA-seq suggested a positive regulation of leukocytes and an upregulation of T cells in LoVo-Reg3A tumor tissue. CD4+ and CD8+ T cells in tumors, splenic Reg3A-reactive IFN-γ+/CD4+ T cells, and serum TNF-α, IFN-γ and IL-17 were significantly increased by Reg3A overexpression. In the ex vivo co-culture experiment, elevated cytotoxic effect, increased proportion of CD3ε+ T cells, and upregulated expressions of TNF-α, IFN-γ and IL-17 were detected in the PBMCs isolated from LoVo-Reg3A cell-xenografted nude mice. In conclusion, high expression of Reg3A could activate and recruit T cells in COAD leading to the cytotoxic tumor-suppressive effect.

Toll-like Receptor 2 Mediated Immune Regulation in Simian Immunodeficiency Virus-Infected Rhesus Macaques

Toll-like receptors (TLRs) are crucial to the innate immune response. They regulate inflammatory reactions by initiating the production of pro-inflammatory cytokines and chemokines. TLRs also play a role in shaping the adaptive immune responses. While this protective response is important for eliminating infectious pathogens, persistent activation of TLRs may result in chronic immune activation, leading to detrimental effects. The role of TLR2 in regulating HIV-1 infection in vivo has yet to be well described. In this study, we used an SIV-infected rhesus macaque model to simulate HIV infection in humans. We evaluated the plasma of the macaques longitudinally and found a significant increase in the soluble TLR2 (sTLR2) level after SIV infection. We also observed an increase in membrane-bound TLR2 (mb-TLR2) in cytotoxic T cells, B cells, and NK cells in PBMC and NK cells in the gut after infection. Our results suggest that sTLR2 regulates the production of various cytokines and chemokines, including IL-18, IL-1RA, IL-15, IL-13, IL-9, TPO, FLT3L, and IL-17F, as well as chemokines, including IP-10, MCP-1, MCP-2, ENA-78, GRO-α, I-TAC, Fractalkine, SDF-1α, and MIP-3α. Interestingly, these cytokines and chemokines were also upregulated after the infection. The positive correlation between SIV copy number and sTLR2 in the plasma indicated the involvement of TLR2 in the regulation of viral replication. These cytokines and chemokines could directly or indirectly regulate viral replication through the TLR2 signaling pathways. When we stimulated PBMC with the TLR2 agonist in vitro, we observed a direct induction of various cytokines and chemokines. Some of these cytokines and chemokines, such as IL-1RA, IL-9, IL-15, GRO-α, and ENA-78, were positively correlated with sTLR2 in vivo, highlighting the direct involvement of TLR2 in the regulation of the production of these factors. Our findings suggest that TLR2 expression may be a target for developing new therapeutic strategies to combat HIV infection.

One-step generation of tumor models by base editor multiplexing in adult stem cell-derived organoids

Optimization of CRISPR/Cas9-mediated genome engineering has resulted in base editors that hold promise for mutation repair and disease modeling. Here, we demonstrate the application of base editors for the generation of complex tumor models in human ASC-derived organoids. First we show efficacy of cytosine and adenine base editors in modeling CTNNB1 hot-spot mutations in hepatocyte organoids. Next, we use C > T base editors to insert nonsense mutations in PTEN in endometrial organoids and demonstrate tumorigenicity even in the heterozygous state. Moreover, drug sensitivity assays on organoids harboring either PTEN or PTEN and PIK3CA mutations reveal the mechanism underlying the initial stages of endometrial tumorigenesis. To further increase the scope of base editing we combine SpCas9 and SaCas9 for simultaneous C > T and A > G editing at individual target sites. Finally, we show that base editor multiplexing allow modeling of colorectal tumorigenesis in a single step by simultaneously transfecting sgRNAs targeting five cancer genes.

Circulating markers of microbial translocation and host response to bacteria with risk of colorectal cancer: a prospective, nested case-control study in men

BACKGROUND

Gut microbial dysbiosis contributes to colorectal cancer (CRC) pathogenesis, possibly mediated in part by increased intestinal permeability to endotoxin lipopolysaccharide (LPS), microbial translocation, and subsequent endotoxemia and inflammation. However, epidemiologic evidence linking circulating markers of microbial translocation with CRC risk is limited.

METHODS

We conducted a prospective, nested case-control study of 261 incident CRC cases and 261 controls (matched on age and time of blood draw) among 18,159 men with pre-diagnostic blood specimens in the Health Professionals Follow-Up Study (1993-2009). We examined three complementary markers of microbial translocation and host response to bacteria, including LPS-binding protein (LBP), soluble CD14 (sCD14), and endotoxincore antibody (EndoCAb) immunoglobulin M (IgM), with subsequent risk of CRC. Unconditional logistic regressions were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs).

FINDINGS

Pre-diagnostic circulating levels of sCD14 were associated with a higher risk of incident CRC. Compared to men in the lowest quartile, the multivariable OR was 1.90 (95% CI, 1.13-3.22) for men in the highest quartile (OR _{per standard deviation [SD] increase}, 1.28; 95%CI 1.06-1.53; P_trend = 0.01). This positive association remained similar after adjusting for C-reactive protein, interleukin-6, and soluble tumor necrosis factor receptor-2, and within strata of putative CRC risk factors. We also observed a suggestive inverse association between EndoCAb IgM and risk of CRC (OR _{per SD increase}, 0.84; 95%CI 0.69-1.02; P_trend = 0.09).

INTERPRETATION

Microbial translocation and host response to bacteria, as reflected by sCD14, is associated with risk of incident CRC in men.

FUNDING

US National Institutes of Health.

Colon cancer transcriptome

Over the last four decades, methodological innovations have continuously changed transcriptome profiling. It is now feasible to sequence and quantify the transcriptional outputs of individual cells or thousands of samples using RNA sequencing (RNA-seq). These transcriptomes serve as a connection between cellular behaviors and their underlying molecular mechanisms, such as mutations. This relationship, in the context of cancer, provides a chance to unravel tumor complexity and heterogeneity and uncover novel biomarkers or treatment options. Since colon cancer is one of the most frequent malignancies, its prognosis and diagnosis seem to be critical. The transcriptome technology is developing for an earlier and more accurate diagnosis of cancer which can provide better protectivity and prognostic utility to medical teams and patients. A transcriptome is a whole set of expressed coding and non-coding RNAs in an individual or cell population. The cancer transcriptome includes RNA-based changes. The combined genome and transcriptome of a patient may provide a comprehensive picture of their cancer, and this information is beginning to affect treatment decision-making in real-time. A full assessment of the transcriptome of colon (colorectal) cancer has been assessed in this review paper based on risk factors such as age, obesity, gender, alcohol use, race, and also different stages of cancer, as well as non-coding RNAs like circRNAs, miRNAs, lncRNAs, and siRNAs. Similarly, they have been examined independently in the transcriptome study of colon cancer.

Tumor microbiome links cellular programs and immunity in pancreatic cancer

Microorganisms are detected in multiple cancer types, including in putatively sterile organs, but the contexts in which they influence oncogenesis or anti-tumor responses in humans remain unclear. We recently developed single-cell analysis of host-microbiome interactions (SAHMI), a computational pipeline to recover and denoise microbial signals from single-cell sequencing of host tissues. Here we use SAHMI to interrogate tumor-microbiome interactions in two human pancreatic cancer cohorts. We identify somatic-cell-associated bacteria in a subset of tumors and their near absence in nonmalignant tissues. These bacteria predominantly pair with tumor cells, and their presence is associated with cell-type-specific gene expression and pathway activities, including cell motility and immune signaling. Modeling results indicate that tumor-infiltrating lymphocytes closely resemble T cells from infected tissue. Finally, using multiple independent datasets, a signature of cell-associated bacteria predicts clinical prognosis. Tumor-microbiome crosstalk may modulate tumorigenesis in pancreatic cancer with implications for clinical management.

Crosstalk between mucosal microbiota, host gene expression, and sociomedical factors in the progression of colorectal cancer

Various omics-based biomarkers related to the occurrence, progression, and prognosis of colorectal cancer (CRC) have been identified. In this study, we attempted to identify gut microbiome-based biomarkers and detect their association with host gene expression in the initiation and progression of CRC by integrating analysis of the gut mucosal metagenome, RNA sequencing, and sociomedical factors. We performed metagenome and RNA sequencing on colonic mucosa samples from 13 patients with advanced CRC (ACRC), 10 patients with high-risk adenoma (HRA), and 7 normal control (NC) individuals. All participants completed a questionnaire on sociomedical factors. The interaction and correlation between changes in the microbiome and gene expression were assessed using bioinformatic analysis. When comparing HRA and NC samples, which can be considered to represent the process of tumor initiation, 28 genes and five microbiome species were analyzed with correlation plots. When comparing ACRC and HRA samples, which can be considered to represent the progression of CRC, seven bacterial species and 21 genes were analyzed. When comparing ACRC and NC samples, 16 genes and five bacterial species were analyzed, and four correlation plots were generated. A network visualizing the relationship between bacterial and host gene expression in the initiation and progression of CRC indicated that Clostridium spiroforme and Tyzzerella nexilis were hub bacteria in the development and progression of CRC. Our study revealed the interactions of and correlation between the colonic mucosal microbiome and host gene expression to identify potential roles of the microbiome in the initiation and progression of CRC. Our results provide gut microbiome-based biomarkers that may be potential diagnostic markers and therapeutic targets in patients with CRC.

EXTL3 could serve as a potential biomarker of prognosis and immunotherapy for prostate cancer and its potential mechanisms

Background

Exostosin like glycosyltransferase 3 (EXTL3) had been reported to be associated with immune deficiency and play prognostic roles in various cancers. However, little is known about the associations between EXTL3 and prostate cancer (PCa). Hence, this article was designed to clarify their associations.

Methods

All original data were downloaded from The Cancer Genome Atlas (TCGA) database. Gene set enrichment analysis (GSEA) and CellMiner database was utilized, respectively, to identify EXTL3-related signaling pathways and drugs. We explored the relationships between EXTL3 expression and immunity to further evaluate the involvement of EXTL3 in response to immunotherapies. LncRNA/RBP/EXTL3 mRNA networks were also identified for its potential mechanism.

Results

Compared with normal prostate samples, EXTL3 was poorly expressed in PCa samples not only in mRNA expression levels, but also in protein expression levels, with worse overall survival (P < 0.05) and this gene could be an independent prognostic biomarker for PCa (both P < 0.05). EXTL3 was revealed to be markedly linked with seven signaling pathways in PCa by GSEA, including calcium, chemokine, ERBB, JAK STAT, MAPK, WNT, oxidative phosphorylation pathways. EXTL3 expression was also revealed to be significantly associated with MSI, immune cells, immune checkpoint molecules, tumor microenvironment and immune cells infiltration. We further predicted immune responses of EXTL3 gene to immunotherapies by TIDE database and the IMvigor210 cohort. A total of six LncRNA/RBP/EXTL3 mRNA networks were eventually identified for its potential mechanisms.

Conclusions

EXTL3 could serve as a potential biomarker of prognosis and immunotherapy for PCa and six LncRNA/RBP/EXTL3 mRNA networks were also identified for its potential mechanisms.

Effects of hyperinsulinemia on pancreatic cancer development and the immune microenvironment revealed through single-cell transcriptomics

BACKGROUND

Hyperinsulinemia is independently associated with increased risk and mortality of pancreatic cancer. We recently reported that genetically reduced insulin production resulted in ~ 50% suppression of pancreatic intraepithelial neoplasia (PanIN) precancerous lesions in mice. However, only female mice remained normoglycemic, and only the gene dosage of the rodent-specific Ins1 alleles was tested in our previous model. Moreover, we did not delve into the molecular and cellular mechanisms associated with modulating hyperinsulinemia.

METHODS

We studied how reduced Ins2 gene dosage affects PanIN lesion development in both male and female Ptf1a^CreER;Kras^LSL-G12D mice lacking the rodent-specific Ins1 gene (Ins1^-/-). We generated control mice having two alleles of the wild-type Ins2 gene (Ptf1a^CreER;Kras^LSL-G12D;Ins1^-/-;Ins2^+/+) and experimental mice having one allele of Ins2 gene (Ptf1a^CreER;Kras^LSL-G12D;Ins1^-/-;Ins2^+/-). We then performed thorough histopathological analyses and single-cell transcriptomics for both genotypes and sexes.

RESULTS

High-fat diet-induced hyperinsulinemia was transiently or modestly reduced in female and male mice, respectively, with only one allele of Ins2. This occurred without dramatically affecting glucose tolerance. Genetic reduction of insulin production resulted in mice with a tendency for less PanIN and acinar-to-ductal metaplasia (ADM) lesions. Using single-cell transcriptomics, we found hyperinsulinemia affected multiple cell types in the pancreas, with the most statistically significant effects on local immune cell types that were highly represented in our sampled cell population. Specifically, hyperinsulinemia modulated pathways associated with protein translation, MAPK-ERK signaling, and PI3K-AKT signaling, which were changed in epithelial cells and subsets of immune cells.

CONCLUSIONS

These data suggest a potential role for the immune microenvironment in hyperinsulinemia-driven PanIN development. Together with our previous work, we propose that mild suppression of insulin levels may be useful in preventing pancreatic cancer by acting on multiple cell types.

Antimicrobial protein REG3A and signaling networks are predictive of stroke outcomes

Regenerating Family Member 3 Alpha (REG3A) is a multifunctional protein with antimicrobial activity, and primarily secreted by the intestine and pancreas. Studies have shown an increased expression of REG3A in systemic inflammatory responses to acute injury and infection, but studies investigating REG3A during the pathogenesis of ischemic stroke are limited. The aims of this study were to examine the associations between arterial expression of REG3A and other arterial inflammatory proteins implicated in stroke pathogenesis, as well as associations between REG3A and markers of poor outcome for ischemic stroke. The University of Kentucky Blood and Clot Thrombectomy Registry and Collaboration (BACTRAC) protocol (clinicaltrials.gov NCT03153683) utilizes thrombectomy to isolate intracranial arterial blood (i.e. distal to thrombus) and systemic arterial blood (i.e. carotid). Samples were analyzed by Olink Proteomics for N = 42 subjects. Statistical analyses of plasma proteins included 2-sample t-tests, spearman and biserial correlations, and robust regression models to elucidate network signaling and association to clinical outcomes. Results indicated that levels of systemic REG3A were positively correlated with inflammatory proteins interleukin IL6 (R = 0.344, p = 0.030) and IL17C (R = 0.468, p = 0.002). 2-sided t- tests examining differences of systemic REG3A within quartiles of NIHSS admission score depicted significant differences between quartiles. Those with NIHSS scores corresponding to moderate and moderate-severe neurofunctional deficits had significantly higher levels of systemic REG3A compared to those with NIHSS scores corresponding to mild and mild-moderate neurofunctional deficits (p = 0.016). STRING analyses of proteins in each robust regression model demonstrated substantial networking between REG3A and other systemic proteins highly relevant to ischemic stroke. The present study provides novel data on systemic REG3A in the context of ischemic stroke. These results demonstrate the influential role of REG3A regarding surrogate functional and radiographic outcomes of stroke severity. Additionally, they provide novel insight into the role of REG3A and related proteins during the complex neuroinflammatory process of ischemic stroke. These data provide a foundation for future studies to investigate REG3A and related networking proteins as potential biomarkers with prognostic potential, as well as potential therapeutic targets.

The regenerating protein 3A: a crucial molecular with dual roles in cancer

Introduction

REG3A, a member of the third subclass of the Reg family, has been found in a variety of tissues but is not detected in immune cells. In the past decade, it has been determined that REG3A expression is regulated by injury, infection, inflammatory stimuli, and pro-cytokines via different signaling pathways, and it acts as a tissue-repair, bactericidal, and anti-inflammatory molecule in human diseases. Recently, the role of REG3A in cancer has received increasing attention. The present article aims to investigate the structure, expression, regulation, function of REG3A, and to highlight the potential role of REG3A in tumors.

Methods

A detailed literature search and data organization were conducted to find information about the role of REG3A in variety of physiological functions and tumors.

Results

Contradictory roles of REG3A have been reported in different tumor models. Some studies have demonstrated that high expression of REG3A in cancers can be oncogenic. Other studies have shown decreased REG3A expression in cancer cells as well as suppressed tumor growth.

Conclusions

Taken together, better understanding of REG3A may lead to new insights that make it a potentially useful target for cancer therapy.

Tumour-Derived Reg3A Educates Dendritic Cells to Promote Pancreatic Cancer Progression

As a pancreatic inflammatory marker, regenerating islet-derived protein 3A (Reg3A) plays a key role in inflammation-associated pancreatic carcinogenesis by promoting cell proliferation, inhibiting apoptosis, and regulating cancer cell migration and invasion. This study aimed to reveal a novel immuno-regulatory mechanism by which Reg3A modulates tumour-promoting responses during pancreatic cancer (PC) progression. In an in vitro Transwell system that allowed the direct co-culture of human peripheral blood-derived dendritic cells (DCs) and Reg3A-overexpressing/ silenced human PC cells, PC cell-derived Reg3A was found to downregulate CD80, CD83 and CD86 expression on educated DCs, increase DC endocytic function, inhibit DC-induced T lymphocyte proliferation, reduce IL-12p70 production, and enhance IL-23 production by DCs. The positive effect of tumour-derived Reg3A-educated human DCs on PC progression was demonstrated in vivo by intraperitoneally transferring them into PC-implanted severe combined immunodeficiency (SCID) mice reconstituted with human T cells. A Reg3A-JAK2/STAT3 positive feedback loop was identified in DCs educated with Reg3A. In conclusion, as a tumour-derived factor, Reg3A acted to block the differentiation and maturation of the most important antigen-presenting cells, DCs, causing them to limit their potential anti-tumour responses, thus facilitating PC escape and progression.

Bile acids increase intestinal marker expression via the FXR/SNAI2/miR-1 axis in the stomach

Purpose

Intestinal metaplasia (IM) is a precancerous lesion that increases the risk of subsequent gastric cancer (GC) development. Previously, miR-1 has been shown to play an essential role in the initiation of bile acid (BA)-induced IM. The objective of the present study was to investigate the mechanism underlying miR-1 inhibition by BA in gastric cells.

Methods

Ingenuity pathway analysis (IPA) was used to identify molecules acting upstream of miR-1. The effects of deoxycholic acid (DCA), FXR and SNAI2 on the expression of intestinal markers were assessed using quantitative real-time PCR (qRT-PCR) and Western blotting. The expression level of major molecules was detected by immunohistochemistry (IHC) in tissue microarrays. The transcriptional regulation of miR-1 was verified using luciferase reporter and chromatin immunoprecipitation (ChIP) assays.

Results

We found that BA treatment caused aberrant expression of FXR and intestinal markers in gastric cells. Augmented FXR led to transcriptional activation of SNAI2, which in turn suppressed the miR-1 promoter. Moreover, we found that compared with normal tissues, the expression levels of both FXR and SNAI2 were increased and positively correlated with each other in IM tissues. Additionally, their expression showed an inverse correlation with that of miR-1 in IM tissues.

Conclusions

Our findings indicate that FXR may be responsible for a series of molecular changes in gastric cells after BA treatment, and that the FXR/SNAI2/miR-1 axis exhibits a crucial role in BA-induced progression of IM. Blocking the FXR-oriented axis may provide a promising approach for IM or even GC treatment.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13402-021-00622-z.

Integrated Analysis of Omics Data Reveal AP-1 as a Potential Regulation Hub in the Inflammation-Induced Hyperalgesia Rat Model

Inflammation-associated chronic pain is a global clinical problem, affecting millions of people worldwide. However, the underlying mechanisms that mediate inflammation-associated chronic pain remain unclear. A rat model of cutaneous inflammation induced by Complete Freund's Adjuvant (CFA) has been widely used as an inflammation-induced pain hypersensitivity model. We present the transcriptomics profile of CFA-induced inflammation in the rat dorsal root ganglion (DRG) via an approach that targets gene expression, DNA methylation, and post-transcriptional regulation. We identified 418 differentially expressed mRNAs, 120 differentially expressed microRNAs (miRNAs), and 2,670 differentially methylated regions (DMRs), which were all highly associated with multiple inflammation-related pathways, including nuclear factor kappa B (NF-κB) and interferon (IFN) signaling pathways. An integrated analysis further demonstrated that the activator protein 1 (AP-1) network, which may act as a regulator of the inflammatory response, is regulated at both the transcriptomic and epigenetic levels. We believe our data will not only provide drug screening targets for the treatment of chronic pain and inflammation but will also shed light on the molecular network associated with inflammation-induced hyperalgesia.

Role of the β-Catenin/REG Iα Axis in the Proliferation of Sessile Serrated Adenoma/Polyps Associated with Fusobacterium nucleatum

Although sessile serrated adenoma/polyps (SSA/Ps) may arise through a pathway different from the traditional adenoma–carcinoma sequence, details of SSA/P tumorigenesis still remain unclear. Fusobacterium nucleatum (Fn) is frequently detected in colorectal cancer (CRC) tissues and may play a pivotal role in colorectal carcinogenesis. Here, we investigated the relationship between Fn and the β-catenin/REG Iα axis in SSA/Ps and their involvement in the proliferation of these lesions. Fn was detected in SSA/Ps by fluorescence in situ hybridization using a Fn-targeted probe, and expression of β-catenin, REG Iα and Ki67 was examined using immunohistochemistry. Sixteen of 30 SSA/P lesions (53.3%) were positive for Fn. Eighteen SSA/P lesions (60%) showed β-catenin immunoreactivity in the tumor cell nuclei. A significant majority of Fn-positive lesions showed nuclear expression of β-catenin (87.5%) and higher REG Iα scores and Ki67 labeling indices relative to Fn-negative lesions. The SSA/P lesions expressing β-catenin in nuclei had significantly higher REG Iα scores and Ki67 labeling indices than those expressing β-catenin on cytomembranes. The REG Iα score was positively correlated with the Ki67 labeling index in SSA/P lesions. The treatment with Wnt agonist SKL2001 promoted nuclear β-catenin translocation and enhanced REG Ia expression in Caco2 cells. Fn may play a role in the proliferation of SSA/P lesions through promotion of β-catenin nuclear translocation and REG Iα expression.

Reg3β: A Potential Therapeutic Target for Tissue Injury and Inflammation-Associated Disorders

Since regenerating islet-derived 3β (Reg3β) was first reported, various studies have been conducted to explore the involvement of Reg3β in a gamut of maladies, such as diabetes, pancreatitis, pancreatic ductal adenocarcinoma, and extrapancreatic maladies such as inflammatory bowel disease, acute liver failure, and myocardial infarction. Surprisingly, there is currently no systematic review of Reg3β. Therefore, we summarize the structural characteristics, transcriptional regulation, putative receptors, and signaling pathways of Reg3β. The exact functional roles in various diseases, especially gastrointestinal and liver diseases, are also discussed. Reg3β plays multiple roles in promoting proliferation, inducing differentiation, preventing apoptosis, and resisting bacteria. The present review may provide new directions for the diagnosis and treatment of gastrointestinal, liver, and pancreatic diseases.

Exosomes secreted by chronic hepatitis B patients with PNALT and liver inflammation grade ≥ A2 promoted the progression of liver cancer by transferring miR-25-3p to inhibit the co-expression of TCF21 and HHIP

OBJECTIVES

The current study aimed to investigate the mechanism by which exosomes secreted by CHB patients with PNALT and liver inflammation grade (≥A2) affected the development of liver cancer.

MATERIALS AND METHODS

Gene expression was assessed by RT-PCR, Western blotting and immunohistochemistry. CCK-8, colony formation, transwell, scratch-wound and flow cytometry assays were used to detect cell viability, proliferation, apoptosis and metastasis. The interaction of TCF21 and HHIP was assessed by co-immunoprecipitation assay. Luciferase reporter was used to detect the combination of TCF21/HHIP and miR-25-3p. Xenograft studies in nude mice manifested tumour growth ability of miR-25-3p. Bioinformatics analyses were conducted using TargetScan, EVmiRNA, TCGA, GEO, DAVID, COEXPEDIA, UALCAN, UCSC and the Human Protein Atlas databases.

RESULTS

CHB-PNALT-Exo (≥A2) promoted the proliferation and metastasis of HepG2.2.15 cells. miR-25-3p was upregulated in CHB-PNALT-Exo (≥A2). miR-25-3p overexpression promoted cell proliferation and metastasis and was related to poor survival in patients with CHB-PNALT (≥A2). The cell proliferation- and metastasis-promoting functions of CHB-PNALT-Exo (≥A2) were abolished by miR-25-3p inhibitors. TCF21 directly interacted with HHIP. Inhibition of TCF21 or HHIP promoted cell proliferation and metastasis. Knockdown of TCF21 or HHIP counteracted the effects of CHB-PNALT-Exo (≥A2) containing miR-25-3p inhibitor on cell proliferation, metastasis and the expression of Ki67, E-cadherin and caspase-3/-9.

CONCLUSIONS

Transfer of miR-25-3p by CHB-PNALT-Exo promoted the development of liver cancer by inhibiting the co-expression of TCF21 and HHIP.

TAK1 regulates the tumor microenvironment through inflammatory, angiogenetic and apoptotic signaling cascades

Transforming growth factor beta-activated kinase 1 (TAK1) has been implicated for its role in inflammatory signaling and as an important mediator of cellular apoptosis and necroptosis in various cell types. Our recent discovery of a first-in-class, potent and selective TAK1 inhibitor, takinib, represents a novel pharmacological tool to evaluate TAK1’s role in cancer. In this study we evaluated the potential therapeutic capacity of TAK1 inhibition on tumor growth and on tumor microenvironment remodeling. In a screen of 16 cancer cell lines, takinib in combination with tumor necrosis factor (TNF) was found to induce cell death (>20%) in 6 out of 16 cell lines. Furthermore, knocking out of TAK1 in MDA-MB-231 cells dramatically increased their sensitization to TNF-mediated apoptosis. In vivo xenographs of MDA-MB-231 TAK1^KO tumors displayed delayed tumor growth and increased overall survival compared to TAK1^WT controls. Histological and proteomic analysis of TAK1^KO tumors showed altered angiogenic signaling and inflammatory signaling via immune cells. Overall, these findings suggest that the targeting of TAK1 in immune mediated cancers may be a novel therapeutic axis.