A Preclinical Model of Chronic Alcohol Consumption Reveals Increased Metastatic Seeding of Colon Cancer Cells in the Liver

Metastatic tumor growth in steatotic liver is promoted by HAS2-mediated fibrotic tumor microenvironment

Steatotic liver enhances liver metastasis of colorectal cancer (CRC), but this process is not fully understood. Steatotic liver induced by a high-fat diet increases cancer-associated fibroblast (CAF) infiltration and collagen and hyaluronic acid (HA) production. We investigated the role of HA synthase 2 (HAS2) in the fibrotic tumor microenvironment in steatotic liver using Has2ΔHSC mice, in which Has2 is deleted from hepatic stellate cells. Has2ΔHSC mice had reduced steatotic liver-associated metastatic tumor growth of MC38 CRC cells, collagen and HA deposition, and CAF and M2 macrophage infiltration. We found that low-molecular weight HA activates Yes-associated protein (YAP) in cancer cells, which then releases connective tissue growth factor to further activate CAFs for HAS2 expression. Single-cell analyses revealed a link between CAF-derived HAS2 and M2 macrophages and CRC cells through CD44; these cells were associated with exhausted CD8+ T cells via programmed death-ligand 1 and programmed cell death protein 1 (PD-1). HA synthesis inhibitors reduced steatotic liver-associated metastasis of CRC, YAP expression, and CAF and M2 macrophage infiltration, and improved response to anti-PD-1 antibody. In conclusion, steatotic liver modulates a fibrotic tumor microenvironment to enhance metastatic cancer activity through a bidirectional regulation between CAFs and metastatic tumors, enhancing the metastatic potential of CRC in the liver.

Curcumin attenuates smoking and drinking activated NF-κB/IL-6 inflammatory signaling axis in cervical cancer

BACKGROUND

High-risk strains of HPV are known to cause cervical cancer. Multiple clinical studies have emphasized that smoking and drinking are critical risk factors for cervical cancer and its high-grade precursors. In this study, we investigated if smoking and/or drinking augment the molecular mechanisms of cervical carcinogenesis and defined a potential therapeutic approach for their attenuation.

METHODS

The impact of benzo[a]pyrene (B[a]P) and/or ethanol (EtOH) exposure on cervical cancer cells was assessed by measuring changes in their cell migration and invasion characteristics. Expression of HPV16 E6/E7, NF-κB, cytokines, and inflammation mediators was determined using qRT-PCR, immunoblotting, ELISA, luciferase reporter assay, and confocal microscopy. Herein, we used curcumin (Cur), and PLGA nanoparticle formulation of curcumin (PLGA-Cur) and determined effectiveness of free Cur and PLGA-Cur formulation on smoking and drinking activated NF-κB/IL-6 mediated inflammatory signaling pathways using in vitro cervical cancer models.

RESULTS

Treatments with B[a]P and/or EtOH altered the expression of HPV16 E6/E7 oncogenes and EMT markers in cervical cancer cells; it also enhanced migration and invasion. In addition, B[a]P and/or EtOH exposure promoted inflammation pathways through TNF-α and NF-κB signaling, leading to IL-6 upregulation and activation of VEGF. The molecular effects caused by B[a]P and/or EtOH exposure were effectively attenuated by curcumin (Cur)/PLGA-Cur treatment.

CONCLUSIONS

These data suggest a molecular link between smoking, drinking, and HPV infectivity in cervical carcinogenesis. In addition, attenuation of these effects by treatment with Cur/PLGA-Cur treatment, implies the role of curcumin in cervical cancer prevention and treatment.

Pre-metastatic niche: formation, characteristics and therapeutic implication

Distant metastasis is a primary cause of mortality and contributes to poor surgical outcomes in cancer patients. Before the development of organ-specific metastasis, the formation of a pre-metastatic niche is pivotal in promoting the spread of cancer cells. This review delves into the intricate landscape of the pre-metastatic niche, focusing on the roles of tumor-derived secreted factors, extracellular vesicles, and circulating tumor cells in shaping the metastatic niche. The discussion encompasses cellular elements such as macrophages, neutrophils, bone marrow-derived suppressive cells, and T/B cells, in addition to molecular factors like secreted substances from tumors and extracellular vesicles, within the framework of pre-metastatic niche formation. Insights into the temporal mechanisms of pre-metastatic niche formation such as epithelial-mesenchymal transition, immunosuppression, extracellular matrix remodeling, metabolic reprogramming, vascular permeability and angiogenesis are provided. Furthermore, the landscape of pre-metastatic niche in different metastatic organs like lymph nodes, lungs, liver, brain, and bones is elucidated. Therapeutic approaches targeting the cellular and molecular components of pre-metastatic niche, as well as interventions targeting signaling pathways such as the TGF-β, VEGF, and MET pathways, are highlighted. This review aims to enhance our understanding of pre-metastatic niche dynamics and provide insights for developing effective therapeutic strategies to combat tumor metastasis.

Alcohol reshapes a liver premetastatic niche for cancer by extra- and intrahepatic crosstalk-mediated immune evasion

Cancer metastatic organotropism is still a mystery. The liver is known to be susceptible to cancer metastasis and alcoholic injury. However, it is unclear whether and how alcohol facilitates liver metastasis and how to intervene. Here, we show that alcohol preferentially promotes liver metastasis in colon-cancer-bearing mice and post-surgery pancreatic cancer patients. The mechanism is that alcohol triggers an extra- and intrahepatic crosstalk to reshape an immunosuppressive liver microenvironment. In detail, alcohol upregulates extrahepatic IL-6 and hepatocellular IL-6 receptor expression, resulting in hepatocyte STAT3 signaling activation and downstream lipocalin-2 (Lcn2) upregulation. Furthermore, LCN2 promotes T cell-exhaustion neutrophil recruitment and cancer cell epithelial plasticity. In contrast, knocking out hepatocellular Stat3 or systemic Il6 in alcohol-treated mice preserves the liver microenvironment and suppresses liver metastasis. This mechanism is reflected in hepatocellular carcinoma patients, in that alcohol-associated signaling elevation in noncancerous liver tissue indicates adverse prognosis. Accordingly, we discover a novel application for BBI608, a small molecular STAT3 inhibitor that can prevent liver metastasis. BBI608 pretreatment protects the liver and suppresses alcohol-triggered premetastatic niche formation. In conclusion, under extra- and intrahepatic crosstalk, the alcoholic injured liver forms a favorable niche for cancer cell metastasis, while BBI608 is a promising anti-metastatic agent targeting such microenvironments.

A Review of Herbal Resources Inducing Anti-Liver Metastasis Effects in Gastrointestinal Tumors via Modulation of Tumor Microenvironments in Animal Models

Liver metastases remain a major obstacle for the management of all types of tumors arising from digestive organs, and the tumor microenvironment has been regarded as an important factor in metastasis. To discover herbal candidates inhibiting the liver metastasis of tumors originating from the digestive system via the modulation of the tumor microenvironment and liver environment, we searched three representative public databases and conducted a systematic review. A total of 21 studies that employed experimental models for pancreatic (9), colon (8), and stomach cancers (4) were selected. The herbal agents included single-herb extracts (5), single compounds (12), and multiherbal decoctions (4). Curcuma longa Linn was most frequently studied for its anti-colon-liver metastatic effects, and its possible mechanisms involved the modulation of tumor microenvironment components such as vascular endothelial cells and immunity in both tumor tissues and circulating cells. The list of herbal agents and their mechanisms produced in this study is helpful for the development of anti-liver metastasis drugs in the future.

Alcohol Use and the Risk of Colorectal Liver Metastasis: A Systematic Mapping Review

The consumption of alcohol has long been associated with the development of liver disease as well as cancers including colorectal cancer (CRC). Leading healthcare concerns include the prevalent use of alcohol and the high burden of CRC mortality. Many CRC deaths are attributed to the development of colorectal liver metastasis (CRLM) as the liver is the foremost site of CRC spread. However, an association has not been defined for the role of alcohol intake and related liver injury with the development of CRLM. Here, a mapping review of recent research was undertaken to evaluate the relationship between alcohol consumption and the risk of CRLM. The literature search revealed 14 articles meeting the inclusion criteria that included patient database analyses and preclinical studies. Most of the human data analyses found alcohol use independently associates with worse CRC outcomes. The preclinical evaluations identified several pathways involved in the alcohol-mediated promotion of CRLM burden and CRC cell metastatic behavior. The limited number of studies identified exposes a significant need for more prospective analyses to define the role of alcohol intake and advanced CRC as well as the translation of preclinical research to fully characterize targetable mechanisms for the generation of new therapeutic options.

CGX, a standardized herbal syrup, inhibits colon-liver metastasis by regulating the hepatic microenvironments in a splenic injection mouse model

Background: Colon-liver metastasis is observed in approximately 50% of patients with colorectal cancer and is a critical risk factor for a low survival rate. Several clinical studies have reported that colon-liver metastasis is accelerated by pathological hepatic microenvironments such as hepatic steatosis or fibrosis. Chunggan syrup (CGX), a standardized 13-herbal mixture, has been prescribed to patients with chronic liver diseases, including fatty liver, inflammation and fibrotic change, based on preclinical and clinical evidence.

Aim of the study: In the present study, we investigated anti-liver metastatic the effects of CGX in a murine colon carcinoma (MC38)-splenic injection mouse model.

Materials and methods: C57BL/6N mice were administered with CGX (100, 200 or 400 mg/kg) for 14 days before or after MC38-splenic injection under normal and high-fat diet (HFD) fed conditions. Also, above experiment was repeated without MC38-splenic injection to explore underlying mechanism.

Results: The number of tumor nodules and liver weight with tumors were sup-pressed by preadministration of CGX in both normal and HFD fed mice. Regarding its mechanisms, we found that CGX administration significantly activated epithelial-cadherin (E-cadherin), but decreased vascular endothelial-cadherin (VE-cadherin) in hepatic tissues under MC38-free conditions. In addition, CGX administration significantly reduced hepatic steatosis, via modulation of lipolytic and lipogenic molecules, including activated adenosine monophosphate activated protein kinase (AMPK) and peroxisome proliferator activated receptor-alpha (PPARα).

Conclusion: The present data indicate that CGX exerts an anti-colon-liver metastatic property via modulation of hepatic lipid related microenvironments.

Very-light alcohol consumption suppresses breast tumor progression in a mouse model

The relationship between alcohol consumption and cancer has no consistent results both in epidemiological studies and animal models. The inaccuracy of alcohol consumption dosage in the experimental design maybe leads to inconsistent results and makes the researchers ignore the effect of very-light alcohol consumption on cancer. To determine the effects of very-light alcohol consumption on cancer, in this study, the manner of gavage was used to control the alcohol consumption accurately. The impacts of age and time of drinking on cancer progression were also evaluated in this study. Here, we find that a certain range of alcohol consumption (from 0.5% w/v to 2.0% w/v) can suppress tumor development in the breast metastasis mouse model by controlling the alcohol consumption dosage accurately. RNA sequencing analyses were performed in primary tumors and related metastases from the NC group and 1.0% w/v group. The results of primary tumors and related metastases indicated that chronic very-light alcohol consumption downregulates breast tumor-associated oncogenes in primary tumors and regulates the immune system and metabolic system in metastatic carcinoma. To provide the public with drinking recommendations, eight commercial alcohol types were investigated at a dosage of 1.0% w/v. Two types of commercial alcohol, red wine (made in France, brand 1) and baijiu (made in China, brand 1), exerted excellent primary tumor and metastasis inhibitory effects. The untargeted metabolomic analysis of commercial alcohol by liquid chromatography-tandem mass spectrometry indicated that baijiu (brand 1) and baijiu (brand 2) exhibited a difference in compositions that can lead to their different anti-cancer effects. These results indicated that a certain range of very light alcohol dosages might have a potential human-cancer inhibition effect.

Possible Immunotherapeutic Strategies Based on Carcinogen-Dependent Subgroup Classification for Oral Cancer

The oral cavity serves as an open local organ of the human body, exposed to multiple external factors from the outside environment. Coincidentally, initiation and development of oral cancer are attributed to many external factors, such as smoking and drinking, to a great extent. This phenomenon was partly explained by the genetic abnormalities traditionally induced by carcinogens. However, more and more attention has been attracted to the influence of carcinogens on the local immune status. On the other hand, immune heterogeneity of cancer patients is a huge obstacle for enhancing the clinical efficacy of tumor immunotherapy. Thus, in this review, we try to summarize the current opinions about variant genetic changes and multiple immune alterations induced by different oral cancer carcinogens and discuss the prospects of targeted immunotherapeutic strategies based on specific immune abnormalities caused by different carcinogens, as a predictive way to improve clinical outcomes of immunotherapy-treated oral cancer patients.

Molecular Mechanisms of Alcohol-Induced Colorectal Carcinogenesis

The etiology of colorectal cancer (CRC) is complex. Approximately, 10% of individuals with CRC have predisposing germline mutations that lead to familial cancer syndromes, whereas most CRC patients have sporadic cancer resulting from a combination of environmental and genetic risk factors. It has become increasingly clear that chronic alcohol consumption is associated with the development of sporadic CRC; however, the exact mechanisms by which alcohol contributes to colorectal carcinogenesis are largely unknown. Several proposed mechanisms from studies in CRC models suggest that alcohol metabolites and/or enzymes associated with alcohol metabolism alter cellular redox balance, cause DNA damage, and epigenetic dysregulation. In addition, alcohol metabolites can cause a dysbiotic colorectal microbiome and intestinal permeability, resulting in bacterial translocation, inflammation, and immunosuppression. All of these effects can increase the risk of developing CRC. This review aims to outline some of the most significant and recent findings on the mechanisms of alcohol in colorectal carcinogenesis. We examine the effect of alcohol on the generation of reactive oxygen species, the development of genotoxic stress, modulation of one-carbon metabolism, disruption of the microbiome, and immunosuppression.

Chronic alcohol exposure promotes HCC stemness and metastasis through β-catenin/miR-22-3p/TET2 axis

Hepatocellular Carcinoma (HCC) patients usually have a high rate of relapse and metastasis. Alcohol, a risk factor for HCC, promotes the aggressiveness of HCC. However, the basic mechanism is still unclear. We used HCC cells and an orthotopic liver tumor model of HCC-LM3 cells for BALB/C nude mice to study the mechanism of alcohol-induced HCC progression. We showed that chronic alcohol exposure promoted HCC cells metastasis and pulmonary nodules formation. First, we identified miR-22-3p as an oncogene in HCC, which promoted HCC cells stemness, tumor growth, and metastasis. Further, we found that miR-22-3p directly targeted TET2 in HCC. TET2, a dioxygenase involved in cytosine demethylation, has pleiotropic roles in hematopoietic stem cells self-renewal. In clinic HCC specimen, TET2 expression was not only decreased by alcohol consumption, but also inversely correlated with miR-22-3p levels. Then, we demonstrated that TET2 depletion promoted HCC cells stemness, tumor growth and metastasis. Furthermore, we identified that β-catenin was an upstream activator of miR-22-3p. In conclusion, this study suggests that chronic alcohol exposure promotes HCC progression and β-catenin/miR-22-3p/TET2 regulatory axis plays an important role in alcohol-promoted HCC malignancy.

CAPS1 promotes colorectal cancer metastasis via Snail mediated epithelial mesenchymal transformation

Colorectal cancer (CRC) is a common gastrointestinal cancer with high mortality rate mostly due to metastasis. Ca²⁺-dependent activator protein for secretion 1 (CAPS1) was originally identified as a soluble factor that reconstitutes Ca²⁺-dependent secretion. In this study, we discovered a novel role of CAPS1 in CRC metastasis. CAPS1 is frequently up-regulated in CRC tissues. Increased CAPS1 expression is associated with frequent metastasis and poor prognosis of CRC patients. Overexpression of CAPS1 promotes CRC cell migration and invasion in vitro, as well as liver metastasis in vivo, without affecting cell proliferation. CAPS1 induces epithelial-mesenchymal transition (EMT), including decreased E-cadherin and ZO-1, epithelial marker expression, and increased N-cadherin and Snail, mesenchymal marker expression. Snail knockdown reversed CAPS1-induced EMT, cell migration and invasion. This result indicates that Snail is required for CAPS1-mediated EMT process and metastasis in CRC. Furthermore, CAPS1 can bind with Septin2 and p85 (subunit of PI3K). LY294002 and wortmanin, PI3K/Akt inhibitors, can abolish CAPS1-induced increase of Akt/GSK3β activity, as well as increase of Snail protein level. Taken together, CAPS1 promotes colorectal cancer metastasis through PI3K/Akt/GSK3β/Snail signal pathway-mediated EMT process.

DNA methylome and transcriptome alterations and cancer prevention by curcumin in colitis-accelerated colon cancer in mice

Inflammation is highly associated with colon carcinogenesis. Epigenetic mechanisms could play an important role in the initiation and progression of colon cancer. Curcumin, a dietary phytochemical, shows promising effects in suppressing colitis-associated colon cancer in azoxymethane-dextran sulfate sodium (AOM-DSS) mice. However, the potential epigenetic mechanisms of curcumin in colon cancer remain unknown. In this study, the anticancer effect of curcumin in suppressing colon cancer in an 18-week AOM-DSS colon cancer mouse model was confirmed. We identified lists of differentially expressed and differentially methylated genes in pairwise comparisons and several pathways involved in the potential anticancer effect of curcumin. These pathways include LPS/IL-1-mediated inhibition of RXR function, Nrf2-mediated oxidative stress response, production of NO and ROS in macrophages and IL-6 signaling. Among these genes, Tnf stood out with decreased DNA CpG methylation of Tnf in the AOM-DSS group and reversal of the AOM-DSS induced Tnf demethylation by curcumin. These observations in Tnf methylation correlated with increased and decreased Tnf expression in RNA-seq. The functional role of DNA methylation of Tnf was further confirmed by in vitro luciferase transcriptional activity assay. In addition, the DNA methylation level in a group of inflammatory genes was decreased in the AOM+DSS group but restored by curcumin and was validated by pyrosequencing. This study shows for the first time epigenomic changes in DNA CpG methylation in the inflammatory response from colitis-associated colon cancer and the reversal of their CpG methylation changes by curcumin. Future clinical epigenetic studies with curcumin in inflammation-associated colon cancer would be warranted.

Epithelial to mesenchymal transition is involved in ethanol promoted hepatocellular carcinoma cells metastasis and stemness

Hepatocellular Carcinoma (HCC) is a malignant tumor with high rate of relapse and metastasis. Ethanol is a well-known risk factor for HCC; it promotes the progression and aggressiveness of HCC. However, the underlying mechanism remains unclear. In clinic studies, we showed that alcohol consumption is positively correlated with TNM stage and vessel invasion; HCC patients with chronic drinking history had faster progression rate and poorer prognosis compared to non-drinkers. In experimental models, ethanol exposure enhanced the metastasis, and invasion of HCC cells. Ethanol exposure increased cancer stem cells (CSC) population and enhanced stemness of HCC cells in vitro and in vivo. Mechanically, we found that ethanol exposure induced epithelial to mesenchymal transition (EMT) through activating Wnt/β-catenin signaling pathway in HCC cells. We further demonstrated that β-catenin siRNA or salinomycin (an inhibitor of Wnt/β-catenin pathway) partially rescued ethanol-induced EMT. In conclusion, this study suggested that ethanol exposure promotes the metastasis and stemness of HCC cells by inducing EMT.

Alcohol and Hepatocellular Carcinoma: Adding Fuel to the Flame

Primary tumors of the liver represent the fifth most common type of cancer in the world and the third leading cause of cancer-related death. Case-control studies from different countries report that chronic ethanol consumption is associated with an approximately 2-fold increased odds ratio for hepatocellular carcinoma (HCC). Despite the substantial epidemiologic data in humans demonstrating that chronic alcohol consumption is a major risk factor for HCC development, the pathways causing alcohol-induced liver cancer are poorly understood. In this overview, we summarize the epidemiological evidence for the association between alcohol and liver cancer, review the genetic, oncogenic, and epigenetic factors that drive HCC development synergistically with ethanol intake and discuss the essential molecular and metabolic pathways involved in alcohol-induced liver tumorigenesis.

The association between clinical outcome and CD8+ lymphocytic infiltration in advanced stages of colorectal cancer differs by latent virus infection in tumour tissue

AIMS

In the near future, an immunoscore based on the quantification of lymphocytic populations can be expected as a fundamental supplement of colorectal cancer (CRC) classification. This study explored whether latent viral infection has an influence on prognostically relevant host immunity in CRC.

METHODS AND RESULTS

CD8⁺ lymphocytic infiltration in three tumour compartments of 121 CRC was compared with clinical data and occurrence of latent infection with herpes simplex virus (HSV1, HSV2), cytomegalovirus (CMV), human papillomavirus (HPV16 and HPV18) in the tumour tissue, which was determined by polymerase chain reaction (PCR). Intraepithelial CD8⁺ lymphocytic infiltration (IE_CD8+ ) showed a trend towards correlation with clinical stage (P = 0.073), significant differences between CRC with and without metastases (P = 0.001) and a significant correlation with overall survival (OS, P = 0.001). Each of these three clinical parameters showed a significant link to IE_CD8+ in the virus DNA-negative (P-values: 0.001-0.036), but no significant differences in the virus DNA-positive subgroup, which is consistent with a moderating effect of virus DNA on these associations. A significant correlation of CD8⁺ infiltration in the invasive margin (IM_CD8+ ) with OS (P = 0.016) was also moderated by virus DNA.

CONCLUSION

Our data suggest a possible influence of latent viral infection on the association between clinical outcome and CD8⁺ lymphocytic infiltration in CRC tissue. After confirmation of these results by large cohort studies, a potential interaction between microbial pathogens and host immunity in CRC and its impact on prognostic immunoscores and/or new therapeutic strategies should be investigated further.

Role of cytokines and chemokines in alcohol-induced tumor promotion

Excessive chronic alcohol consumption has become a worldwide health problem. The oncogenic effect of chronic alcohol consumption is one of the leading concerns. The mechanisms of alcohol-induced tumorigenesis and tumor progression are largely unknown, although many factors have been implicated in the process. This review discusses the recent progress in this research area with concentration on alcohol-induced dysregulation of cytokines and chemokines. Based on the available evidence, we propose that alcohol promotes tumor progression by the dysregulation of the cytokine/chemokine system. In addition, we discuss specific transcription factors and signaling pathways that are involved in the action of these cytokines/chemokines and the oncogenic effect of alcohol. This review provides novel insight into the mechanisms of alcohol-induced tumor promotion.

Enhanced colorectal cancer metastases in the alcohol-injured liver

Metastatic liver disease is a major cause of mortality in colorectal cancer (CRC) patients. Alcohol consumption is a noted risk factor for secondary cancers yet the role of alcoholic liver disease (ALD) in colorectal liver metastases (CRLM) is not defined. This work evaluated tumor cell colonization in the alcoholic host liver using a novel preclinical model of human CRC liver metastases. Immunocompromised Rag1-deficient mice were fed either ethanol (E) or isocaloric control (C) diets for 4 weeks prior to intrasplenic injection of LS174T human CRC cells. ALD and CRLM were evaluated 3 or 5 weeks post-LS174T cell injection with continued C/E diet administration. ALD was confirmed by increased serum transaminases, hepatic steatosis and expression of cytochrome P4502E1, a major ethanol-metabolizing enzyme. Alcohol-mediated liver dysfunction was validated by impaired endocytosis of asialoorosomucoid and carcinoembryonic antigen (CEA), indicators of hepatocellular injury and progressive CRC disease, respectively. Strikingly, the rate and burden of CRLM was distinctly enhanced in alcoholic livers with metastases observed earlier and more severely in E-fed mice. Further, alcohol-related increases (1.5-3.0 fold) were observed in the expression of hepatic cytokines (TNF-α, IL-1 beta, IL-6, IL-10) and other factors noted to be involved in the colonization of CRC cells including ICAM-1, CCL-2, CCL-7, MMP-2, and MMP-9. Also, alcoholic liver injury was associated with altered hepatic localization as well as increased circulating levels of CEA released from CRC cells. Altogether, these findings indicate that the alcoholic liver provides a permissive environment for the establishment of CRLM, possibly through CEA-related inflammatory mechanisms.