The interplay between diet and the enteric nervous system in the pathophysiology of colorectal cancer.

Colorectal cancer (CRC) represents the third most diagnosed cancer worldwide, with 1.9 million new cases reported annually. Notwithstanding the progress made in the field of therapeutic modalities and the advent of early diagnosis, CRC continues to represent the second most common cause of cancer-related mortality. The interactions between cancer cells and enteric nervous system (ENS) neurons are of great importance for the prevention and/or progression of CRC. Dietary factors play an important role in regulating both processes. The consumption of foods rich in polyphenols, omega-3 fatty acids, and the use of probiotics has been shown to promote proper ENS function, which in turn has been demonstrated to indirectly inhibit the development or progression of CRC. Conversely, a diet comprising a high proportion of saturated fats and refined sugars can induce oxidative stress and inflammation, which exacerbates the disease. Nutritional education and dietary modifications can reduce the incidence of new cases of CRC and improve prognosis. Further research into the potential anti- or pro-cancer effects of food substances is recommended.

Obesity and Colorectal Cancer: A Narrative Review.

Background and Objectives: Cancer is a multicausal disease, and environmental, cultural, socioeconomic, lifestyle, and genetic factors can influence the risk of developing cancer. Colorectal cancer (CRC) stands as the third most common cancer globally. Some countries have observed a rise in the incidence of CRC, especially among young people. This increase is associated with lifestyle changes over the last few decades, including changes in diet patterns, a sedentary lifestyle, and obesity. Currently, obesity and overweight account for approximately 39% of the world's population and increase the risk of overall mortality of certain cancer types. This study aims to conduct a literature review examining the association between obesity and CRC. Materials and Methods: This narrative review explored the pathophysiological mechanisms, treatment strategies, and challenges related to obesity and CRC. Results: Several studies have established a clear causal relationship between obesity and CRC, showing that individuals with morbid obesity are at a higher risk of developing colorectal cancer. The adipose tissue, particularly the visceral, secretes proinflammatory cytokines, such as TNF-alpha, interleukin-6, and C-reactive protein. Chronic inflammation is closely linked to cancer initiation and progression, with a complex interplay of molecular mechanisms underlying this association. Obesity can complicate the treatment of CRC due to several factors, reducing the therapeutic effectiveness and increasing the risk for adverse events during treatment. Dietary modification, calorie restriction, and other types of weight-control strategies can reduce the risk of CRC development and improve treatment outcomes. Conclusions: Obesity is intricately linked to CRC development and progression, making it a crucial target for intervention, whether through diet therapy, physical exercises, medical therapy, or bariatric surgery.

Resting-State Brain Function Alteration in Colorectal Cancer Patients.

BACKGROUND AND PURPOSE: To investigate the abnormal pattern of altered functional activity in the brain and the neuroimaging mechanisms underlying the cognitive impairment of patients with colorectal cancer (CRC) via resting-state functional magnetic resonance imaging (rs-fMRI). MATERIALS AND METHODS: CRC patients (n = 56) and healthy controls (HCs) (n = 50) were studied. The participants underwent rs-fMRI scans and the Montreal Cognitive Assessment (MoCA). The amplitude of low-frequency fluctuations (ALFF), degree centrality (DC), regional homogeneity (ReHo), and MoCA scores, were calculated for participants. RESULTS: The scores of executives, visuospatial, memory, language and attention were lower in CRC patients. ReHo and ALFF values in the left postcentral gyrus, ReHo values in the right postcentral gyrus, ALFF and DC values in the left middle occipital gyrus, ReHo and DC values in the right lingual gyrus, DC values in the right angular gyrus and precuneus, and ALFF values in the left middle temporal gyrus decreased conspicuously in the CRC patients. CONCLUSION: CRC patients have abnormal resting state function, mainly in the brain areas involved in cognitive function. The overlapping brain regions with abnormal functional indicators are in the middle occipital gyrus, postcentral gyrus, and lingual gyrus. This study reveals the potential biological pathways involved in brain impairment and neurocognitive decline in patients with CRC.

The combination of handgrip strength and CONUT predicts overall survival in patients with gastrointestinal cancer: A multicenter cohort study.

BACKGROUND: The controlled nutritional status score (CONUT) and handgrip strength (HGS) were both predictive indexes for the prognosis of cancers. However, the combination of CONUT and HGS for predicting the prognosis of gastrointestinal cancer had not been developed. This study aimed to explore the combination of CONUT and HGS as the potential predictive prognosis in patients with gastric and colorectal cancer. METHODS: A cohort study was conducted with gastric and colorectal cancer patients in multicenter in China. Based on the optimal HGS cutoff value for different sex, the HGS cutoff value was determined. The patients were divided into high and low HGS groups based on their HGS scores. A CONUT score of 4 or less was defined as a low CONUT, whereas scores higher than 4 were defined as high CONUT. The Kaplan-Meier method was used to create survival curves, and the log-rank test was used to compare time-event relationships between groups. A Cox proportional hazard regression model was used to determine independent risk factors for overall survival (OS). RESULTS: A total 2177 gastric and colorectal patients were enrolled in this study, in which 1391 (63.9%) were men (mean [SD] age, 66.11 [11.60] years). Multivariate analysis revealed that patients with high HGS had a lower risk of death than those with low HGS (hazard ratio [HR],0.87; 95% confidence interval [CI], 0.753-1.006, P = 0.06), while high CONUT had a higher risk of death than those with low CONUT (HR, 1.476; 95% CI, 1.227-1.777, P < 0.001). Patients with both low HGS and high CONUT had 1.712 fold increased risk of death (HR, 1.712; 95% CI, 1.364-2.15, P < 0.001). Moreover, cancer type and sex were stratified and found that patients with high CONUT and low HGS had lower survival rate than those with low CONUT and high HGS in both gastric or colorectal cancer, and both male and female. CONCLUSION: A combination of low HGS and high CONUT was associated with poor prognosis in patients with gastrointestinal cancer, which could probably predict the prognosis of gastrointestinal cancer more accurate than HGS or CONUT alone.

[Huaier triggering mitochondria apoptosis in colorectal cancer cells through oxidative stress].

This study investigates the specific mechanisms of Huaier-induced mitochondrial apoptosis in colorectal cancer. HCT116 and SW480 cells were subjected to Huaier treatment. Cell proliferation and migration capabilities were examined through CCK-8 and scratch experiments, respectively. Apoptotic cells were clarified with Annexin-PE staining. DCFH-DA staining, malondialdehyde(MDA), and glutathione(GSH) were used to evaluate the oxidative stress damage level of cells. MitoSOX and JC-1 probes were used to selectively target mitochondria reactive oxygen species(mtROS) and mitochondria membrane potential(MMP) for the evaluation of mitochondria damage. Western blot(WB) experiment was performed to determine apoptosis proteins and PINK1/Parkin pathway. Experiments reveal that in different concentrations of Huaier treatment, the proliferation and migration capabilities of HCT116 and SW480 cells were both restrained. Additionally, mitochondrial apoptosis was activated. Compared with the control group, excessive ROS in colorectal cancer cells was generated in the Huaier group, while MDA increased, and GSH decreased, indicating oxidative stress damage. mtROS increased, and MMP decreased in colorectal cancer cells treated with Huaier, indicating mitochondrial damage. WB result revealed that Huaier suppressed the PINK1/Parkin pathway, hindered the clearance of impaired mitochondria, and subsequently facilitated apoptosis. In conclusion, Huaier impairs colorectal cancer cells through oxidative stress and mitochondria damage. Furthermore, it suppressed the PINK1/Parkin pathway, promoting mitochondria apoptosis in colorectal cancer cells.

Fasting hyperglycaemia and fatty liver drive colorectal cancer: a retrospective analysis in 1145 patients.

BACKGROUND: Metabolic dysfunction-associated steatotic liver disease (MASLD) represents the hepatic manifestation of increased adiposopathy, whose pathogenetic features have been proposed as tumourigenic triggers for colorectal cancer (CRC). We aim to identify specific metabolic signatures involved in CRC development that may be used as non-invasive biomarkers, paving the way for specific and personalized strategies of CRC prevention and early detection. METHODS: We retrospectively assessed CRC onset during a time frame of 8 years in a cohort of 1145 out-patients individuals who had previously been evaluated for Metabolic Syndrome. RESULTS: 28 patients developed CRC. No association between CRC development and visceral and general obesity was detected, while baseline fasting plasma glucose (FPG) and non-invasive liver fibrosis scores were significantly higher in patients with CRC, compared to those who did not develop cancer. Liver steatosis and MASLD were more frequently diagnosed in patients who developed CRC compared to no cancer developers. Canonical correlations among metabolic biomarkers were not present in CRC developers, differently from no cancer group. In ROC analysis, FPG and non-invasive scores also showed good sensitivity and specificity in predicting colon cancer. We then calculated ORs for metabolic biomarkers, finding that higher FPG and non-invasive scores were associated with an increased risk of developing CRC. CONCLUSION: MASLD and increased FPG may play a role in the clinical background of CRC, bringing to light the fascinating possibility of a reversed gut-liver axis communication in the pathogenesis of CRC. Thus, the use of non-invasive scores of fatty liver may be helpful to predict the risk of CRC and serve as novel prognostic factors for prevention and therapeutic strategies.

Colorectal cancer-associated mutations impair EphB1 kinase function.

Erythropoietin-producing hepatoma (Eph) receptor tyrosine kinases regulate the migration and adhesion of cells that are required for many developmental processes and adult tissue homeostasis. In the intestinal epithelium, Eph signaling controls the positioning of cell types along the crypt-villus axis. Eph activity can suppress the progression of colorectal cancer (CRC). The most frequently mutated Eph receptor in metastatic CRC is EphB1. However, the functional effects of EphB1 mutations are mostly unknown. We expressed and purified the kinase domains of WT and five cancer-associated mutant EphB1 and developed assays to assess the functional effects of the mutations. Using purified proteins, we determined that CRC-associated mutations reduce the activity and stability of the folded structure of EphB1. By mammalian cell expression, we determined that CRC-associated mutant EphB1 receptors inhibit signal transducer and activator of transcription 3 and extracellular signal-regulated kinases 1 and 2 signaling. In contrast to the WT, the mutant EphB1 receptors are unable to suppress the migration of human CRC cells. The CRC-associated mutations also impair cell compartmentalization in an assay in which EphB1-expressing cells are cocultured with ligand (ephrin B1)-expressing cells. These results suggest that somatic mutations impair the kinase-dependent tumor suppressor function of EphB1 in CRC.

eIF3i promotes colorectal cancer cell survival via augmenting PHGDH translation.

Translational regulation is one of the decisive steps in gene expression, and its dysregulation is closely related to tumorigenesis. Eukaryotic translation initiation factor 3 subunit i (eIF3i) promotes tumor growth by selectively regulating gene translation, but the underlying mechanisms are largely unknown. Here, we show that eIF3i is significantly increased in colorectal cancer (CRC) and reinforces the proliferation of CRC cells. Using ribosome profiling and proteomics analysis, several genes regulated by eIF3i at the translation level were identified, including D-3-phosphoglycerate dehydrogenase (PHGDH), a rate-limiting enzyme in the de novo serine synthesis pathway that participates in metabolic reprogramming of tumor cells. PHGDH knockdown significantly represses CRC cell proliferation and partially attenuates the excessive growth induced by eIF3i overexpression. Mechanistically, METTL3-mediated N6-methyladenosine modification on PHGDH mRNA promotes its binding with eIF3i, ultimately leading to a higher translational rate. In addition, knocking down eIF3i and PHGDH impedes tumor growth in vivo. Collectively, this study not only uncovered a novel regulatory mechanism for PHGDH translation but also demonstrated that eIF3i is a critical metabolic regulator in human cancer.

CREB1 contributes colorectal cancer cell plasticity by regulating lncRNA CCAT1 and NF-κB pathways.

The CREB1 gene encodes an exceptionally pleiotropic transcription factor that frequently dysregulated in human cancers. CREB1 can regulate tumor cell status of proliferation and/or migration; however, the molecular basis for this switch involvement in cell plasticity has not fully been understood yet. Here, we first show that knocking out CREB1 triggers a remarkable effect of epithelial-mesenchymal transition (EMT) and leads to the occurrence of inhibited proliferation and enhanced motility in HCT116 colorectal cancer cells. By monitoring 45 cellular signaling pathway activities, we find that multiple growth-related pathways decline significantly while inflammatory pathways including NF-κB are largely upregulated in comparing between the CREB1 wild-type and knocked out cells. Mechanistically, cells with CREB1 knocked out show downregulation of MYC as a result of impaired CREB1-dependent transcription of the oncogenic lncRNA CCAT1. Interestingly, the unbalanced competition between the coactivator CBP/p300 for CREB1 and p65 leads to the activation of the NF-κB pathway in cells with CREB1 disrupted, which induces an obvious EMT phenotype of the cancer cells. Taken together, these studies identify previously unknown mechanisms of CREB1 in CRC cell plasticity via regulating lncRNA CCAT1 and NF-κB pathways, providing a critical insight into a combined strategy for CREB1-targeted tumor therapies.

Reversing chemorefraction in colorectal cancer cells by controlling mucin secretion.

Fifteen percent of colorectal cancer (CRC) cells exhibit a mucin hypersecretory phenotype, which is suggested to provide resistance to immune surveillance and chemotherapy. We now formally show that CRC cells build a barrier to chemotherapeutics by increasing mucins' secretion. We show that low levels of KChIP3, a negative regulator of mucin secretion (Cantero-Recasens et al., 2018), is a risk factor for CRC patients' relapse in a subset of untreated tumours. Our results also reveal that cells depleted of KChIP3 are four times more resistant (measured as cell viability and DNA damage) to chemotherapeutics 5-fluorouracil + irinotecan (5-FU+iri.) compared to control cells, whereas KChIP3-overexpressing cells are 10 times more sensitive to killing by chemotherapeutics. A similar increase in tumour cell death is observed upon chemical inhibition of mucin secretion by the sodium/calcium exchanger (NCX) blockers (Mitrovic et al., 2013). Finally, sensitivity of CRC patient-derived organoids to 5-FU+iri. increases 40-fold upon mucin secretion inhibition. Reducing mucin secretion thus provides a means to control chemoresistance of mucinous CRC cells and other mucinous tumours.

Tissue miR-200c-3p and circulating miR-1290 as potential prognostic biomarkers for colorectal cancer.

Epithelial-mesenchymal transition (EMT)-related cancers generally elicit low immune responses. EMT is regulated by several microRNAs (miRNAs) in cancers. Thus, this study aimed to evaluate the prognostic potential of EMT-related miRNAs as biomarkers in colorectal cancer (CRC). Formalin-fixed paraffin-embedded tumor and normal tissue and plasma samples were obtained from 65 patients with pathologically confirmed CRC. In addition, plasma samples were obtained from 30 healthy volunteers. Immunohistochemical staining for E-cadherin, ZEB1, PD-1, PD-L1, CD3, CD4, CD8, Foxp3, and CD68 was conducted on tissue samples. Droplet digital polymerase chain reaction (ddPCR) analysis was performed to evaluate miR-21-5p, 34a-5p, 138-5p, 200a-3p, 200b-5p, 200c-3p, 630, 1246, and 1290 expression in tissue samples and miR-630, 1246, and 1290 expression in plasma samples. miR-21-5p, 34a-5p, 630, 1246, and 1290 expression was higher in tumor tissues than in normal tissues (P < 0.05). EMT was significantly associated with reduced tumor-infiltrating T cells. Moreover, miR-21-5p, miR-34a-5p, miR-200a-3p, and miR-200c-3p expression was negatively correlated with T cell density (P < 0.05). High tissue levels of miR-200c-3p were associated with poor overall survival (OS) (P < 0.001). CRC patients with the EMT phenotype had poor OS; however, PD-L1 positivity and abundant PD-1 positive immune cells were correlated with better OS (P < 0.05). miR-1246 and miR-1290 levels were significantly higher in the plasma of patients with CRC than in the plasma of healthy controls (P < 0.05). High plasma levels of miR-1290 were correlated with advanced stage and poor OS (P < 0.05). The tissue expression of miR-200c-3p and plasma levels of miR-1290 measured by ddPCR indicate their potential as prognostic biomarkers for CRC.

Home-based, supervised, and mixed exercise intervention on functional capacity and quality of life of colorectal cancer patients: a meta-analysis.

This systematic review and meta-analysis of randomized controlled trials tested the effects of home-based, supervised, or mixed exercise interventions on the functional capacity (FC) and quality of life (QoL) in colorectal cancer patients. A literature search was performed using the PubMed, Embase, Cochrane, and Medline databases. Two reviewers screened the literature through March 10, 2021 for studies related to exercise and colorectal cancer. Of the 1161 screened studies in the initial search, 13 studies met the eligibility criteria (home-based = 6 studies; supervised or mixed = 7 studies). Overall, 706 patients were enrolled in the trials, and 372 patients were submitted to home-based, supervised, or mixed exercise intervention. The overall results from the main meta-analysis showed a significant effect regarding supervised or mixed intervention (6 studies; p = 0.002; I2 = 43%; PI 0.41-1.39); however, no significant effect was observed for home-based intervention (5 studies; p = 0.05; I2 = 25%; PI - 0.34-0.76). A sensitivity analysis based on studies with intervention adherence ≥ 80% (home-based = 3 studies; supervised or mixed = 4 studies) revealed that home-based intervention or intervention entirely supervised or with some level of supervision (mixed) are effective in improving the QoL and FC of CRC patients. In summary, this meta-analysis verified that supervised and home-based exercise can modify QoL and FC when intervention adherence ≥ 80%. Regardless of the supervision characteristics, future RCTs are strongly encouraged to provide a detailed description of the exercise variables in physical interventions for CRC prescription. This perspective will allow a refined exercise prescription for patients with CRC, mainly according to their clinical status.

Targeting MUCL1 protein inhibits cell proliferation and EMT by deregulating ß­catenin and increases irinotecan sensitivity in colorectal cancer.

With >1.85 million cases and 850,000 deaths annually, colorectal cancer (CRC) is the third most common cancer detected globally. CRC is an aggressive malignancy with metastasis and, in spite of advances in improved treatment regimen, distant disease failure rates remain disappointingly high. Mucin­like 1 (MUCL1) is a small glycoprotein highly expressed mainly in breast cancer. The involvement of the MUCL1 protein in CRC progression and the underlying mechanism have been largely unknown. The aim of the present study was to investigate the MUCL1 expression profile and its functional significance in CRC. The Cancer Genome Atlas dataset revealed that MUCL1 expression was higher in colorectal tumor compared with normal tissues. MUCL1 was also revealed to be expressed in human CRC cell lines. The results demonstrated that MUCL1 promoted cell proliferation and colony formation, confirming its oncogenic potential. Silencing MUCL1 with short interfering RNA inhibited the protein expression of Bcl2 family proteins, such as Bcl2 and BclxL. Targeting MUCL1 resulted in significant inhibition in cell invasive and migratory behavior of HT­29 and SW620 cells. In addition, the expression of E­cadherin increased whereas the expression of vimentin decreased in MUCL1­silenced cells, confirming inhibition of epithelial­mesenchymal transition (EMT) process. Thus, it was revealed that MUCL1 plays a notable role in cell invasion and migration by inhibiting EMT in CRC. Mechanistically, MUCL1 drives ß­catenin activation by Ser­552 phosphorylation, nuclear accumulation and transcriptional activation. Targeting MUCL1 increases the drug sensitivity of CRC cells towards irinotecan. These findings thus demonstrated that MUCL1 acts as a modifier of other pathways that play an important role in CRC progression and MUCL1 was identified as a potential target for CRC therapeutics.

Agreement between GLIM and PG-SGA for diagnosis of malnutrition depends on the screening tool used in GLIM.

BACKGROUND & AIM: The Global Leadership Initiative on Malnutrition (GLIM) has suggested a process for the diagnosis of malnutrition. The process consists of applying an existing screening tool for malnutrition screening, followed by malnutrition diagnostics, and finally categorization of malnutrition severity (moderate or severe) according to specific GLIM criteria. However, it is not known how well the GLIM process agrees with other diagnostic tools used in the current clinical practice. The aim of this study was to validate the GLIM process against the Patient Generated-Subjective Global Assessment (PG-SGA) when different screening tools were applied in the screening step of the GLIM process. METHODS: Colorectal cancer (CRC) patients from the ongoing CRC-NORDIET study were included. For the GLIM process, the patients were first screened for malnutrition using either 1) Nutritional risk screening, first 4 questions (NRS-2002-4Q), 2) Malnutrition Screening Tool (MST), 3) Malnutrition Universal Screening Tool (MUST) or 4) the PG-SGA short form (PG-SGA-SF). The GLIM malnutrition diagnosis was then based on combining the result from each of the screening methods with the etiological and phenotypic GLIM-criteria including weight loss, BMI and fat free mass. In parallel, the patients were diagnosed using the PG-SGA methodology categorizing the patients into either A: well nourished, B: moderately malnourished or C: severely malnourished. The four different GLIM based diagnoses were then validated against the diagnosis obtained by the PG-SGA tool. Sensitivity, specificity and positive predictive value (PPV) were calculated to evaluate validity. RESULTS: In total, 426 patients were included (mean age: 66, ±8 years) at a mean time of 166 (±56) days after surgery. The GLIM diagnosis based on the four different screening tools identified 10-24% of the patients to be malnourished, of which 3-8% were severely malnourished. The PG-SGA method categorized 15% as moderately malnourished (PG-SGA: category B) and no patients as severely malnourished (PG-SGA: category C). The agreement between the PG-SGA and GLIM process was in general low, but differed according to the tools: PG-SGA SF (sensitivity 47%, PPV 71%), MST (sensitivity 56%, PPV 47%), NRS-2002-4Q (sensitivity 63%, PPV 53%) and MUST (sensitivity 53%, PPV 34%). CONCLUSION: In this cross-sectional study of patients with CRC, the concordance between the GLIM-criteria and PG-SGA depended on the screening tool used in the GLIM process. Malnutrition frequency based on the GLIM process schould be reported with and without the use of a screening tool.

Functional roles of cytokines in infectious disease associated colorectal carcinogenesis.

Infection processes induce various soluble factors that are carcinogens in humans; therefore, research into the soluble factors of chronic disease released from cells that have been infected with parasites is warranted. Parasitic infections in host cells release high levels of IFNγ. Studies have hypothesised that parasitosis-associated carcinogenesis might be analogous to colorectal cancers developed from inflammatory bowel diseases, whereby various cytokines and chemokines are secreted during chronic inflammation. IL-18 and IL-21 are other factors that might be involved in the development of colorectal cancer in schistosomiasis patients and patients with other infections. IL-21 has profound effects on tumour growth and immunosurveillance of colitis-associated tumourigenesis, thereby emphasising its involvement in the pathogenesis of colorectal cancer. The prominent role of IL-21 in antitumour effects greatly depends on the enhanced cytolytic activity of NK cells and the pathogenic role of IL-21, which is often associated with enhanced risks of cancer and chronic inflammatory processes. As IL-15 is also related to chronic disease, it is believed to also play a role in the antitumour effect of colorectal carcinogenesis. IL-15 generates and maintains long-term CD8+ T cell immunity against T. gondii to control the infection of intracellular pathogens. The lack of IL-15 in mice contributes to the downregulation of the IFNγ-producing CD4+ T cell response against acute T. gondii infection. IL-15 induces hyperplasia and supports the progressive growth of colon cancer via multiple functions. The limited role of IL-15 in the development of NK and CD8+ T cells suggests that there may be other cytokines compensating for the loss of the IL-15 gene.

Lactobacillus plantarum-derived metabolites sensitize the tumor-suppressive effects of butyrate by regulating the functional expression of SMCT1 in 5-FU-resistant colorectal cancer cells.

A critical obstacle to the successful treatment of colorectal cancer (CRC) is chemoresistance. Chemoresistant CRC cells contribute to treatment failure by providing a mechanism of drug lethargy and modifying chemoresistance-associated molecules. The gut microbiota provide prophylactic and therapeutic effects by targeting CRC through anticancer mechanisms. Among them, Lactobacillus plantarum contributes to the health of the host and is clinically effective in treating CRC. This study confirmed that 5-fluorouracil (5-FU)-resistant CRC HCT116 (HCT116/5FUR) cells acquired butyrate-insensitive properties. To date, the relationship between 5-FU-resistant CRC and butyrate resistance has not been elucidated. Here, we demonstrated that the acquisition of butyrate resistance in HCT116/5FUR cells was strongly correlated with the inhibition of the expression and function of SMCT1, a major transporter of butyrate in colonocytes. L. plantarum-cultured cell-free supernatant (LP) restored the functional expression of SMCT1 in HCT116/5FUR cells, leading to butyrate-induced antiproliferative effect and apoptosis. These results suggest that LP has a synergistic effect on the SMCT1/butyrate-mediated tumor suppressor function and is a potential chemosensitizer to overcome dual 5-FU and butyrate resistance in HCT116 cells.

IRF1 Inhibits Autophagy-Mediated Proliferation of Colorectal Cancer via Targeting ATG13.

IRF1 is a nuclear transcription factor that mediates interferon effects and appears to have anti-tumor activity. To determine the roles of IRF1 in colorectal cancer (CRC), we investigated the effects of IRF1 in CRC cells. We found that IRF1 inhibit cell proliferation and tumor growth. Under starvation conditions, IRF1 enhanced apoptosis and reduced autophagic flux. ATG13, an important factor of autophagy complex, was confirmed as a target of IRF1. These findings indicated that IRF1 function as a tumor suppressor in CRC and inhibit autophagy through ATG13, targeting this pathway may provide new insights into the molecular mechanisms of CRC progression.

Malnutrition modifies the response to multimodal prehabilitation: a pooled analysis of prehabilitation trials.

Patients with colorectal cancer are at risk of malnutrition before surgery. Multimodal prehabilitation (nutrition, exercise, stress reduction) readies patients physically and mentally for their operation. However, it is unclear whether extent of malnutrition influences prehabilitation outcomes. We conducted a pooled analysis from five 4-week multimodal prehabilitation trials in colorectal cancer surgery (prehabilitation: n = 195; control: n = 71). Each patient's nutritional status was evaluated at baseline using the Patient-Generated Subjective Global Assessment (PG-SGA; higher score, greater need for treatment of malnutrition). Functional walking capacity was measured with the 6-minute walk test distance (6MWD) at baseline and before surgery. A multivariable mixed effects logistic regression model evaluated the potential modifying effect of PG-SGA on a clinically meaningful change of ≥19 m in 6MWD before surgery. Multimodal prehabilitation increased the odds by 3.4 times that colorectal cancer patients improved their 6MWD before surgery as compared with control (95% confidence interval (CI): 1.6 to 7.3; P = 0.001, n = 220). Nutritional status significantly modified this outcome (P = 0.007): Neither those patients with PG-SGA ≥9 (adjusted odds ratio: 1.3; 95% CI: 0.23 to 7.2, P = 0.771, n = 39) nor PG-SGA <4 (adjusted odds ratio: 1.3; 95% CI: 0.5 to 3.8, P = 0.574, n = 87) improved in 6MWD with prehabilitation. In conclusion, baseline nutritional status modifies prehabilitation effectiveness before colorectal cancer surgery. Patients with a PG-SGA score 4-8 appear to benefit most (physically) from 4 weeks of multimodal prehabilitation. Novelty: Nutritional status is an effect modifier of prehabilitation physical function outcomes. Patients with a PG-SGA score 4-8 benefited physically from 4 weeks of multimodal prehabilitation.

EMT-cancer cells-derived exosomal miR-27b-3p promotes circulating tumour cells-mediated metastasis by modulating vascular permeability in colorectal cancer.

BACKGROUND: Metastasis is the main cause of death in colorectal cancer (CRC). Circulating tumour cells (CTCs) are regarded as the precursor cells of metastasis. The CTCs, which underwent epithelial-mesenchymal transition (EMT), are associated with metastasis and responsible for poor prognosis. EMT cancer cells modulate endothelial permeability in the invasive front and facilitate cancer cell intravasation, resulting in CTCs-mediated distant metastasis. Exosomes derived from cancer cells are key mediators of cancer-host intercommunication. However, the mechanism by which EMT-tumour cells-derived exosomes modulate vascular permeability and promote CTCs generation has remained unclear. METHODS: Exosomes isolation and purification were conducted by ultra-centrifugation. Exosomal miRNA was identified by sequencing followed by quantitative PCR. In vitro co-culture assay experiments were conducted to evaluate the effect of exosomal miR-27b-3p on the permeability of blood vessel endothelium. Dual-luciferase reporter assay, chromatin immunoprecipitation (ChIP) and RNA immunoprecipitation (RIP) were performed to investigate the underlying mechanism by which miR-27b-3p is packaged into exosomes. A mouse model was established to determine the role of exosomal miR-27b-3p in blood vessel permeability modulation in vivo. RESULTS: We found that EMT-CRC cells attenuate the blood vessel barrier by transferring miR-27b-3p to human umbilical vein endothelial cells (HUVECs) in exosomes. Mechanically, miR-27b-3p atteuated the expression of vascular endothelial cadherin (VE-Cad) and p120 at the post-transcriptional level by binding to 3'-untranslated region of VE-Cad and p120 directly. The packaging of miR-27b-3p into exosomes was induced by heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1), which activated by STAT3. Clinically, miR-27b-3p up-regulated in CRC tissues. Plasma exosomal miR-27b-3p was positively correlated with malignant progression and CTC count in CRC patients. Our study reveals a novel mechanism by which EMT-CRC cells promote metastasis, increasing blood vessel permeability and facilitating the generation of CTCs. CONCLUSION: Exosomal miR-27b-3p secreted by EMT-CRC cells increases blood vessel permeability and facilitates the generation of CTCs. Exosomal miR-27b-3p may become a promising biomarker for CRC metastasis.