Self-assembled PROTACs enable protein degradation to reprogram the tumor microenvironment for synergistically enhanced colorectal cancer immunotherapy.

Both ß-catenin and STAT3 drive colorectal cancer (CRC) growth, progression, and immune evasion, and their co-overexpression is strongly associated with a poor prognosis. However, current small molecule inhibitors have limited efficacy due to the reciprocal feedback activation between STAT3 and ß-catenin. Inspired by the PROteolysis TArgeting Chimera (PROTAC), a promising pharmacological modality for the selective degradation of proteins, we developed a strategy of nanoengineered peptide PROTACs (NP-PROTACs) to degrade both ß-catenin and STAT3 effectively. The NP-PROTACs were engineered by coupling the peptide PROTACs with DSPE-PEG via disulfide bonds and self-assembled into nanoparticles. Notably, the dual degradation of ß-catenin and STAT3 mediated by NP-PROTACs led to a synergistic antitumor effect compared to single-target treatment. Moreover, NP-PROTACs treatment enhanced CD103+ dendritic cell infiltration and T-cell cytotoxicity, alleviating the immunosuppressive microenvironment induced by ß-catenin/STAT3 in CRC. These results highlight the potential of NP-PROTACs in facilitating the simultaneous degradation of two pathogenic proteins, thereby providing a novel avenue for cancer therapy.

MiRNA expression affects survival in patients with obstructive sleep apnea and metastatic colorectal cancer.

Introduction: The relationship between obstructive sleep apnea (OSA) and cancer has been recognized for some time now. However, little is known about the mechanisms by which sleep apnea promotes tumorigenesis and the impact of OSA on survival after cancer diagnosis. In the last few years, research has focused on the exploration of different biomarkers to understand the mechanisms underlying this relationship and miRNAs, non-coding single strands of about 22 nucleotides that post-transcriptionally regulate gene expression, have emerged as possible actors of this process.The aim of the study was to evaluate the impact of OSA on survival of metastatic colorectal cancer (mCRC) patients based on the expression of specific miRNAs. Methods: The expression of 6 miRNAs, respectively miR-21, miR-23b, miR-26a, miR-27b, miR-145 and miR-210, was analyzed by qRT-PCR in patients' sera. Response to first-line therapy, Kaplan-Meier curves of overall and progression-free survival were used to evaluate survival in mCRC patients with and without OSA stratified for the expression of miRNAs. Results: The expression of miR-21, miR-23b, miR-26a and miR-210 was significantly upregulated in mCRCs with OSA compared to no OSA. In mCRC patients with OSA and increasing expression of miR-21, miR-23b, miR-26a and miR-210 risk of progression after first-line therapy was higher and both overall and progression-free survival were significantly worst. Conversely, as miR-27b and miR-145 expression increased, the life expectancy of patients diagnosed with OSA and mCRC improved markedly. Conclusions: This study highlights the relevance of specific miRNAs on OSA in mCRCs and their significance as non-invasive biomarkers in predicting the prognosis in patients with mCRC and OSA.

Analysis of lens cloudiness during endoscopic submucosal dissection procedures: Effects of a novel lens cleaner.

Objectives: We aimed to identify independent factors for intraoperative endoscopic lens cloudiness during gastric and colorectal endoscopic submucosal dissections, investigate the effectiveness of Cleastay, an endoscope anti-fog solution, and examine factors associated with severe submucosal fat deposition. Methods: A total of 220 patients who underwent gastric or colorectal endoscopic submucosal dissections in two institutions between January 2022 and October 2023 were included. Significant factors related to cloudiness were determined using univariate and multivariate analyses. Patient background and tumor characteristics related to severe submucosal fat deposition were investigated, and the degree of intraoperative endoscopic lens cloudiness and outcomes were compared between the Cleash and Cleastay groups. Results: In the multivariate analysis, factors increasing lens cloudiness included long procedure time (odds ratio [OR], 17.51; 95% confidence interval [CI], 1.52-202.08), stomach (vs. colon; OR, 5.08; 95% CI, 1.99-12.96), and severe submucosal fat deposition (OR, 12.19; 95% CI, 5.02-29.60). Conversely, the use of Cleastay (vs. Cleash; OR, 0.066; 95% CI, 0.021-0.21) was identified as a factor reducing cloudiness. Location analysis revealed that severe submucosal fat deposition was more common in the upper stomach and right colon. Conclusions: It was suggested that Cleastay is more useful for endoscopic submucosal dissection of the upper stomach and right colon, where severe submucosal fat deposition is expected.

Tubeimoside-I, an inhibitor of HSPD1, enhances cytotoxicity of oxaliplatin by activating ER stress and MAPK signaling pathways in colorectal cancer.

ETHNOPHARMACOLOGICAL RELEVANCE: Tubeimoside-I (TBM) promotes various cancer cell death by increasing the reactive oxygen species (ROS) production. However, the specific molecular mechanisms of TBM and its impact on oxaliplatin-mediated anti-CRC activity are not yet fully understood. AIM OF THE STUDY: To elucidate the therapeutic effect and underlying molecular mechanism of TBM on oxaliplatin-mediated anti-CRC activity. MATERIALS AND METHODS: 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), colony formation, wound healing assays and flow cytometry were conducted to investigate the changes in cell phenotypes and ROS generation. Real-time quantitative PCR (qRT-PCR) and western blotting were performed to detect the expressions of related mRNA and proteins. Finally, mouse xenograft models demonstrated that synergistic anti-tumor effects of combined treatment with TBM and oxaliplatin. RESULTS: The synergistic enhancement of the anti-tumor effects of oxaliplatin in colon cancer cells by TBM involved in the regulation of ROS-mediated endoplasmic reticulum (ER) stress, C-jun-amino-terminal kinase (JNK), and p38 MAPK signaling pathways. Mechanistically, TBM increased ROS generation in colon cancer cells by inhibiting heat shock protein 60 (HSPD1) expression. Knocking down HSPD1 increased TBM-induced antitumor activity and ROS generation in colon cancer cells. The mouse xenograft tumor models further validated that the combination therapy exhibited stronger anti-tumor effects than monotherapy alone. CONCLUSIONS: Combined therapy with TBM and oxaliplatin might be an effective therapeutic strategy for some CRC patients.

Genes da instabilidade de microssatélites no câncer colorretal: papel na inflamação e estresse oxidativo / Microsatellite instability genes in colorectal cancer: role in inflammation and oxidative stress

A instabilidade de microssatélites é um fenômeno genético caracterizado pela alteração na repetição de sequências de nucleotídeos conhecidas como microssatélites. Esta instabilidade pode ocorrer devido a defeitos nos genes reparadores de DNA, como os genes MLH1, MSH2, MSH6 e PMS2. A inflamação crônica tem sido associada ao desenvolvimento do câncer colorretal. Os genes da instabilidade de microssatélites estão envolvidos na regulação da resposta inflamatória, podendo influenciar a progressão tumoral. Estudos demonstraram que a presença de instabilidade de microssatélites em tumores colorretais está relacionada a uma maior infiltração de células imunes, como linfócitos T, macrófagos e neutrófilos, que podem modular a resposta inflamatória no microambiente tumoral. O estresse oxidativo é caracterizado pelo desequilíbrio entre a produção de espécies reativas de oxigênio e a capacidade antioxidante do organismo e desempenha um papel importante na carcinogênese. Os genes da instabilidade de microssatélites podem influenciar a resposta ao estresse oxidativo, afetando a capacidade das células tumorais de lidar com o dano oxidativo e promovendo a sobrevivência celular. O objetivo deste trabalho consiste na compreensão dos genes envolvidos na instabilidade de microssatélites no câncer colorretal e como eles contribuem para o desenvolvimento da doença, relacionando com processos inflamatórios e estresse oxidativo nas células tumorais. Justifica-se pela necessidade de compreensão das interconexões entre a instabilidade de microssatélites, inflamação e o estresse oxidativo em pacientes com câncer colorretal.

Microsatellite instability is a genetic phenomenon characterized by changes in the repetition of nucleotide sequences known as microsatellites. This instability may occur due to defects in DNA repair genes, such as the MLH1, MSH2, MSH6 and PMS2 genes. Chronic inflammation has been linked to the development of colorectal cancer. Microsatellite instability genes are involved in regulating the inflammatory response and may influence tumor progression. Studies have shown that the presence of microsatellite instability in colorectal tumors is related to a greater infiltration of immune cells, such as T lymphocytes, macrophages and neutrophils, which can modulate the inflammatory response in the tumor microenvironment. Oxidative stress is characterized by the imbalance between the production of reactive oxygen species and the body's antioxidant capacity and plays an important role in carcinogenesis. Microsatellite instability genes can influence the response to oxidative stress, affecting the ability of tumor cells to deal with oxidative damage and promoting cell survival. The objective of this work is to understand the genes involved in microsatellite instability in colorectal cancer and how they contribute to the development of the disease, relating it to inflammatory processes and oxidative stress in tumor cells. It is justified by the need to understand the interconnections between microsatellite instability, inflammation and oxidative stress in patients with colorectal cancer.

ChanLingGao alleviates intestinal mucosal barrier damage and suppresses the onset and progression of Colorectal cancer in AOM/DSS murine model.

BACKGROUND: The occurrence of Colorectal Cancer (CRC) is influenced by various factors, including host susceptibility, immune imbalance, and environmental triggers. Numerous studies have underscored the critical role of chronic intestinal inflammation and dysbiosis in the development of CRC. Traditional Chinese Medicine (TCM) holds unique advantages in regulating the intricate process of and comprehensive treatment for systemic disease. Previous investigations by our team have confirmed the anti-cancer properties of the TCM compound ChanLingGao (CLG), including inhibiting cancer cell migration, and alleviating bone cancer pain. However, the mechanisms underlying its efficacy in alleviating chronic intestinal inflammation, modulating the gut microbiota, and protecting the intestinal mucosal barrier remain largely unknown. PURPOSE: This study aims to explore the inhibitory effects of CLG on CRC tumors in mice and its potential mechanisms. METHODS: A chronic inflammation-related CRC mouse model was established using AOM/DSS. The study examined the mechanisms of intestinal inflammation and tumor cell proliferation through intestinal histological morphology. High-throughput sequencing was employed to analyze changes in gut microbiota diversity and intestinal mucosal barrier integrity in CRC mice. Based on network pharmacology target prediction and Wnt/ß-catenin signaling pathway analysis, the study analyzed and discussed the potential mechanisms of CLG on CRC. RESULTS: CLG significantly ameliorated weight loss and increased survival rates in CRC mice, while suppressing tumor growth in the intestinal tract. Post-CLG treatment improved intestinal inflammation in CRC mice, with a significant reduction in inflammatory factors IL-6, IL-23 and LCN2, and inhibition of tumor cell proliferation markers Proliferating Cell Nuclear Antigen (PCNA), Recombinant Ki-67 Protein (Ki-67), and CCND1. 16sV3-V4 region microbiota sequencing results indicated that CLG improved dysbiosis, and significantly increased the abundance of Akkermansia bacteria, further promoting the expression of MUC-2 protein and mucin secretion. Additionally, CLG prevented the disruption of intestinal epithelial cell junction proteins Occludin, Claudin-1, ZO-1, and E-cadherin, restored the number of goblet cells, and preserved the integrity of the intestinal mucosal barrier. Further experiments suggested that CLG inhibited abnormal activation of the Wnt/ß-catenin pathway, and its potential mechanism in maintaining mucosal barrier integrity might be related to blocking Wnt/ß-catenin pathway. CONCLUSIONS: This study demonstrates that CLG can inhibit CRC tumor growth by regulating the gut microbiota structure, reducing intestinal inflammation, improving intestinal mucosal barrier function, and inhibiting the complex process of cancer cell proliferation. This provides new clinical insights into the "membrane-oriented" treatment of CRC with CLG.

Design, synthesis, molecular modeling and evaluation of 2,4-diaminopyrimidine analogues as promising colorectal cancer drugs.

The potential of cyclin-dependent kinases (CDKs) as therapeutic targets in cancer treatment is well established. In this study, we present our investigation into a group of 2,4-diaminopyrimidine derivatives that potently inhibit CDK9 and are cytotoxic when tested in colorectal cancer cell lines. We designed and synthesized forty analogues by altering substitutions at C-2 and C-4 position of the pyrimidine system. Among them, compounds 16 h and 16j exhibited strong inhibitory potency against both CDK9 enzymes (IC50 = 11.4 ± 1.4 nM, IC50 = 10.2 ± 1.3 nM respectively) with a significant preference for one over the other, and cytotoxic potency (IC50 = 61 ± 2 nM, IC50 = 20 ± 1 nM respectively) against HCT-116 was discovered through substantial modifications to its structure. Further investigations revealed that compounds 16 h and 16j were directly bound to CDK9, resulting in the suppression of its downstream signaling pathway. This inhibition of cell proliferation occurred by impeding the progression of the cell cycle and inducing apoptosis in cells by suppressing the phosphoryl RNA pol II Ser2. Significantly, compound 16 h and 16j effectively suppressed tumor growth in a xenograft mouse model and exhibited no apparent toxicity. This indicates that CDK9 inhibitors hold great potential as a therapeutic approach for colorectal cancer treatment. Therefore, the aforementioned discoveries are vital for the development of CDK9 inhibitors for the treatment of cancer.

An explore method for quick screening biomarkers based on effective enrichment capacity and data mining.

Protein glycosylation acts as a crucial role in regulating protein function and maintaining cellular homeostasis. Efficient peptide enrichment can be utilized to effectively solve the inherent challenges of protein glycosylation analysis to search unknown cancer biomarkers. In this research, a low dimensional porous hydrophilic nanosheets with a multi-level porous structure (Co-MOF-SiO2@HA) was synthetized via an easy one-pot method for the efficient enrichment of the N-glycopeptides in the digests of complex biosamples. The synthetized nanosheets Co-MOF-SiO2@HA demonstrated excellent enriching performances including a high enrichment capacity (300 mg g-1 calculated), a spectacular selectivity (IgG digests and BSA digests at the molar ratio of 1/1200), and an excellent spatial confinement ability (IgG digests, IgG and BSA at the molar ratio of 1/1000/1000). As an explore result, after the enrichment of human colorectal cancer tissue and human healthy tissue by the nanosheets, several proteins related to cancers and one protein directly related to well-known human colorectal cancer were identified by detecting the corresponding glycopeptides. It presented the potential value of the feasibility of this analysis mode by nanosheets Co-MOF-SiO2@HA in proteomic analysis.

Euphorbia Pekinensis Rupr. sensitizes colorectal cancer to PD-1 blockade by remodeling the tumor microenvironment and enhancing peripheral immunity.

BACKGROUND: Immune checkpoint blockade, such as monoclonal antibodies targeting programmed cell death protein 1 (PD-1), has been a major breakthrough in the treatment of several cancers, but has limited effect in colorectal cancer (CRC), which is a highly prevalent cancer worldwide. Current chemotherapy-based strategies to boost PD-1 response have many limitations. And the role of peripheral immunity in boosting PD-1 response continues to attract attention. Therefore, candidate combinations of PD-1 blockade need to be drugs with multi-targets and multi-modulatory functions. However, it is still unknown whether traditional Chinese medicines with such property can enhance the applicability and efficacy of PD-1 blockade in colorectal cancer. METHODS: Euphorbia Pekinensis extract (EP) was prepared and the constituents were analyzed by HPLC. CRC cells were used for in vitro experiments, including cell viability assay, colony formation assay, flow cytometry for 7-AAD staining, western blotting for caspase 3 and caspase 7, HMGB1 and ATP detection. An orthotopic CT26 mouse model was subsequently used to investigate the combination of EP and PD-1 blockade therapy. Tumor volume and tumor weight were assessed, tumor tissues were subjected to histopathological HE staining and TUNEL staining, and tumor-infiltrating immune cells were evaluated by immunofluorescence staining. RNA-sequencing, target prediction and pathway analysis were further employed to explore the mechanism. Molecular docking and cellular thermal shift assay (CETSA) were utilized to verify the direct target of the core component of EP. And, loss-of-function analysis was carried to confirm the upstream-downstream relationship. Flow cytometry was employed to analyze CD8+ T cells in the peripheral blood and spleen. RESULTS: The main constituents of EP are diterpenoids and flavonoids. EP dramatically suppresses CRC cell growth and exerts its cytotoxic effect by triggering immunogenic cell death in vitro. Moreover, EP synergizes with PD-1 blockade to inhibit tumorigenesis in tumor-bearing mice. Disruption of ISX nuclear localization by helioscopinolide E is a central mechanism of EP-induced apoptosis in CRC cell. Meanwhile, EP activates immune response by upregulating Phox2b to reshape the immune microenvironment. In addition, EP regulates peripheral immunity by regulating the T cell activation and proliferation, and the ratio of CD8+ T cells in peripheral blood is drastically increased, thereby enhancing the therapeutic efficacy of anti-PD1 immunotherapy. CONCLUSION: EP triggers intra-tumor immunogenic cell death and modulates the immunoregulatory signaling to elicit the tumor immunogenicity. Moreover, EP participates in transcriptional activation of immune response-related pathways. Consequently, multiple stimulating functions of EP on macro- and micro-immune potentiates the anti-tumor effect of PD-1 blockade in CRC.

Mortality and rate of hospitalization stratified by patients' BMI in a colonoscopy screening - a cross sectional analysis of data from Polish Colonoscopy Screening Platform.

BACKGROUND: Currently, it remains unknown whether there is an association between body mass index (BMI) and complications during screening colonoscopy; hence, it remains unclear whether BMI should be considered a risk factor in pre-procedural assessments. The aim of this study was to compare mortality and unplanned hospitalization rates before and after colonoscopy stratified by patients' BMI. MATERIAL AND METHODS: This was a retrospective cohort study of individuals who underwent screening colonoscopy as part of the Polish Colonoscopy Screening Program (PCSP). The included individuals were followed up for mortality and hospitalization episodes from 42 days prior to colonoscopy to 30 days after the procedure. Rates for the endpoints were calculated, compared, and adjusted for available data. Weighted averages of stratum-specific rates were calculated. Additional subanalyses were performed for sex and procedure type (screening colonoscopy without biopsy, colonoscopy with biopsy, or colonoscopy with polypectomy). RESULTS: A total of 55390 individuals who underwent colonoscopy between years 2012-2015 were included. Obese individuals had significantly more hospitalizations than non-obese patients (1.94% versus 0%, p = .038). Analysis of adjusted hospitalization rates stratified by sex revealed that obese males had significantly higher related hospitalizations' rates before or after and after colonoscopy. Unadjusted and adjusted mortality rates after screening colonoscopy did not reveal significant differences between BMI categories. CONCLUSIONS: Overweight and obesity are not clinically relevant risk factors for mortality and hospitalization six weeks before or 30 days after screening colonoscopy. Obese males may be more likely to require hospital care after colonoscopy.

Antigen-independent activation is critical for the durable antitumor effect of GUCY2C-targeted CAR-T cells.

BACKGROUND: Chimeric antigen receptor (CAR)-T cells face many obstacles in solid tumor therapy, including heterogeneous antigen expression and inefficient T cell persistence. Guanylyl cyclase C (GUCY2C) has been identified as a suitable tumor antigen for targeted therapy due to its intestinal-restricted expression pattern in normal tissues and steady overexpression in gastrointestinal tumors, especially colorectal cancer. An antigen-sensitive and long-lasting CAR-T cell targeting GUCY2C was investigated in this study. METHODS: Using constructed tumor cell lines with various GUCY2C expression densities, we screened out an antigen-sensitive single chain variable fragment (scFv) that enabled CAR-T cells to efficiently eradicate the GUCY2C lowly expressed tumor cells. CAR-T cells with different compositions of the hinge, transmembrane and costimulatory domains were also constructed for selection of the long-lasting CAR-T format with durable antitumor efficacy in vitro and in tumor-bearing mice. The underlying mechanism was further investigated based on mutation of the hinge and transmembrane domains. RESULTS: We found that the composition of the antigen-sensitive scFv, CD8α hinge, CD8α transmembrane, and CD28 costimulatory domains boosted CAR-T cells to rapidly kill tumors, maintain high expansion capacity, and long-term efficacy in various colorectal cancer models. The durable antitumor function was attributed to the optimal CAR tonic signaling that conferred CAR-T cells with autonomous activation, proliferation, survival and cytokine release in the absence of antigen stimulation. The tonic signaling was associated with the length and the cysteine residues in the CD8α hinge and transmembrane domains. CONCLUSIONS: This study demonstrated a potent GUCY2C-targeted CAR-T cell for gastrointestinal tumor therapy and highlights the importance of adequate tonic signaling for effective CAR-T cell therapy against solid tumors.

Mitotic spindle positioning protein serves as prognostic biomarker in patients with colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) ranks among the most aggressive types of cancer globally. Currently, clinical tumor prognostic biomarkers still lack accuracy. Mitotic spindle positioning (MISP) protein connects microtubules to the actin cytoskeleton and adhesive plaques, playing a critical role in spindle positioning, orientation, and the process of cell division. MISP can regulate the malignant biological functions of pancreatic cancer and intrahepatic cholangiocarcinoma and it acts as biomarker for prognosis, but its role in CRC remains unclear. METHODS: This study has collected 37 CRC tissue samples and 37 corresponding adjacent nontumor tissue samples, and 57 additional CRC tissues samples. Clinical data were obtained from the patients with CRC. MISP mRNA and protein expression levels were analyzed in normal control and CRC tissues using the GEPIA and Human Protein Atlas website. MISP protein levels in the collected tissues were analyzed using immunohistochemistry. RESULTS: MISP mRNA and protein expression levels were significantly increased in CRC tissues compared to adjacent nontumor tissues. Higher MISP protein levels were associated with distant metastasis, recurrence, and lower survival rates. Kaplan-Meier analysis showed that high expression levels of MISP protein were associated with recurrence and death in CRC patients. In addition, a high expression level of MISP protein, lymph node metastasis, and distance metastasis were risk factors for recurrence and a poor prognosis in patients with CRC. CONCLUSION: Elevated MISP protein correlated with tumor metastasis, recurrence, and lower survival rates in patients with CRC, and thus, MISP has the potential to become a prognostic marker for CRC.

DNA demethylation triggers cell free DNA release in colorectal cancer cells.

BACKGROUND: Liquid biopsy based on cell-free DNA (cfDNA) analysis holds significant promise as a minimally invasive approach for the diagnosis, genotyping, and monitoring of solid malignancies. Human tumors release cfDNA in the bloodstream through a combination of events, including cell death, active and passive release. However, the precise mechanisms leading to cfDNA shedding remain to be characterized. Addressing this question in patients is confounded by several factors, such as tumor burden extent, anatomical and vasculature barriers, and release of nucleic acids from normal cells. In this work, we exploited cancer models to dissect basic mechanisms of DNA release. METHODS: We measured cell loss ratio, doubling time, and cfDNA release in the supernatant of a colorectal cancer (CRC) cell line collection (N = 76) representative of the molecular subtypes previously identified in cancer patients. Association analyses between quantitative parameters of cfDNA release, cell proliferation, and molecular features were evaluated. Functional experiments were performed to test the impact of modulating DNA methylation on cfDNA release. RESULTS: Higher levels of supernatant cfDNA were significantly associated with slower cell cycling and increased cell death. In addition, a higher cfDNA shedding was found in non-CpG Island Methylator Phenotype (CIMP) models. These results indicate a positive correlation between lower methylation and increased cfDNA levels. To explore this further, we exploited methylation microarrays to identify a subset of probes significantly associated with cfDNA shedding and derive a methylation signature capable of discriminating high from low cfDNA releasers. We applied this signature to an independent set of 176 CRC cell lines and patient derived organoids to select 14 models predicted to be low or high releasers. The methylation profile successfully predicted the amount of cfDNA released in the supernatant. At the functional level, genetic ablation of DNA methyl-transferases increased chromatin accessibility and DNA fragmentation, leading to increased cfDNA release in isogenic CRC cell lines. Furthermore, in vitro treatment of five low releaser CRC cells with a demethylating agent was able to induce a significant increase in cfDNA shedding. CONCLUSIONS: Methylation status of cancer cell lines contributes to the variability of cfDNA shedding in vitro. Changes in methylation pattern are associated with cfDNA release levels and might be exploited to increase sensitivity of liquid biopsy assays.

Navigating therapeutic prospects by modulating autophagy in colorectal cancer.

Colorectal cancer (CRC) remains a leading cause of death globally despite the improvements in cancer treatment. Autophagy is an evolutionarily conserved lysosomal-dependent degradation pathway that is critical in maintaining cellular homeostasis. However, in cancer, autophagy may have conflicting functions in preventing early tumour formation versus the maintenance of advanced-stage tumours. Defective autophagy has a broad and dynamic effect not just on cancer cells, but also on the tumour microenvironment which influences tumour progression and response to treatment. To add to the layer of complexity, somatic mutations in CRC including tumour protein p53 (TP53), v-raf murine sarcoma viral oncogene homolog B1 (BRAF), Kirsten rat sarcoma viral oncogene homolog (KRAS), and phosphatase and tensin homolog (PTEN) can render chemoresistance by promoting a pro-survival advantage through autophagy. Recent studies have also reported autophagy-related cell deaths that are distinct from classical autophagy by employing parts of the autophagic machinery, which impacts strategies for autophagy regulation in cancer therapy. This review discusses the molecular processes of autophagy in the evolution of CRC and its role in the tumour microenvironment, as well as prospective therapeutic methods based on autophagy suppression or promotion. It also highlights clinical trials using autophagy modulators for treating CRC, underscoring the importance of autophagy regulation in CRC therapy.

PANX2 promotes malignant transformation of colorectal cancer and 5-Fu resistance through PI3K-AKT signaling pathway.

Colorectal cancer(CRC) is the third deadliest cancer in the world, with a high incidence, aggressiveness, poor prognosis, and resistant to drugs. 5-fluorouracil (5-FU) is the most commonly used drug for the chemotherapeutic of CRC, however, CRC is resistant to 5-FU after a period of treatment. Therefore, there is an urgent need to explore the underlying molecular mechanisms of CRC resistance to 5-FU. In the present study, we found that the expression of PANX2 was increased in CRC tissues and metastatic tissues from the TCGA database. The K-M survival curve showed that the high expression of PANX2 was associated with poor cancer prognosis. GDSC database showed that the IC50 of 5-Fu in the PANX2 high expression group was significantly higher, and the results were verified in CRC cells. In vitro cell function and in vivo tumorigenesis experiments showed that PANX2 promoted CRC cell proliferation, clone formation, migration and tumorigenesis in vivo.WB result revealed that PANX2 may lead to resistance to 5-Fu in CRC by affecting the PI3K-AKT signaling pathway. Overall, PANX2 regulates CRC proliferation, clone formation, migration, and 5-Fu resistance by PI3K-AKT signaling pathway.

Microarray analysis points to LMNB1 and JUN as potential target genes for predicting metastasis promotion by etoposide in colorectal cancer.

Etoposide is a second-line chemotherapy agent widely used for metastatic colorectal cancer. However, we discovered that etoposide treatment induced greater motility potential in four colorectal cancer cell lines. Therefore, we used microarrays to test the mRNA of these cancer cell lines to investigate the mechanisms of etoposide promoting colorectal cancer metastasis. Differentially expressed genes (DEGs) were identified by comparing the gene expression profiles in samples from etoposide-treated cells and untreated cells in all four colorectal cancer cell lines. Next, these genes went through the Gene Set Enrichment Analysis (GSEA), Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) Pathway analysis. Among the top 10 genes including the upregulated and downregulated, eight genes had close interaction according to the STRING database: FAS, HMMR, JUN, LMNB1, MLL3, PLK2, STAG1 and TBL1X. After etoposide treatment, the cell cycle, metabolism-related and senescence signaling pathways in the colorectal cancer cell lines were significantly downregulated, whereas necroptosis and oncogene pathways were significantly upregulated. We suggest that the differentially expressed genes LMNB1 and JUN are potential targets for predicting colorectal cancer metastasis. These results provide clinical guidance in chemotherapy, and offer direction for further research in the mechanism of colorectal cancer metastasis.

Histological Risk Factors for Lymph Node Metastasis in pT1 Colorectal Cancer: Does Submucosal Invasion Depth Really Matter?

OBJECTIVE: After endoscopic resection of colorectal cancer with submucosal invasion (pT1 CRC), additional surgical treatment is recommended if deep submucosal invasion (DSI) is present. This study aimed to further elucidate the risk factors for lymph node metastasis (LNM) in patients with pT1 CRC, especially the effect of DSI on LNM. METHODS: Patients with pT1 CRC who underwent lymph node dissection were selected. The Chi-square test and multivariate logistic regression were used to analyze the relationship between clinicopathological characteristics and LNM. The submucosal invasion depth (SID) was measured via 4 methods and analyzed with 3 cut-off values. RESULTS: Twenty-eight of the 239 patients presented with LNM (11.7%), and the independent risk factors for LNM included high histological grade (P=0.003), lymphovascular invasion (LVI) (P=0.004), intermediate to high budding (Bd 2/3) (P=0.008), and cancer gland rupture (CGR) (P=0.008). Moreover, the SID, width of submucosal invasion (WSI), and area of submucosal invasion (ASI) were not significantly different. When one, two, three or more risk factors were identified, the LNM rates were 1.1% (1/95), 12.5% (7/56), and 48.8% (20/41), respectively. CONCLUSION: Indicators such as the SID, WSI, and ASI are not risk factors for LNM and are subjective in their measurement, which renders them relatively inconvenient to apply in clinical practice. In contrast, histological grade, LVI, tumor budding and CGR are relatively straightforward to identify and have been demonstrated to be statistically significant. It would be prudent to focus on these histological factors rather than subjective measurements.

MiR-5195-3p predicts clinical prognosis and represses colorectal cancer progression by targeting TLR4/MyD88 signaling.

BACKGROUND: Recent studies have highlighted the role of miR-5195-3p in suppressing cell growth in various cancers. However, the specific functional impact of miR-5195-3p in colorectal cancer (CRC) remain to be fully clarified. The importance of miR-5195-3p in CRC was evaluated, aiming to uncover its underlying molecular mechanism and identify it as a potential therapeutic target for CRC. RESULTS: Our research has shown that miR-5195-3p is markedly under-expressed in CRC tissues and cell cultures, with its reduced presence associated with a higher TNM stage, lymphatic invasion, and unfavorable survival outcome. Ectopic miR-5195-3p expression curtailed proliferation, migration, and invasion of SW1116 and HT29 cells. Additionally, we discovered that miR-5195-3p directly targets and negatively influences Toll-like receptor 4 (TLR4) in CRC cells. Moreover, an inverse relationship was noted between miR-5195-3p and TLR4 expression in CRC tissue samples. Notably, restoring TLR4 expression counteracted miR-5195-3p's suppressive impact on cell growth, motility, invasiveness, epithelial-mesenchymal transition (EMT), and the TLR4/MyD88 signaling pathway in SW1116 and HT29 cells. CONCLUSIONS: MiR-5195-3p suppresses the CRC cellular functions through the downregulation of TLR4/MyD88 signaling, indicating that targeting miR-5195-3p might offer a viable therapeutic strategy for CRC.