Complete remission in a pretreated, microsatellite-stable, KRAS-mutated colon cancer patient after treatment with sintilimab and bevacizumab and platinum-based chemotherapy: a case report and literature review.

Metastatic colon cancer remains an incurable disease, and it is difficult for existing treatments to achieve the desired clinical outcome, especially for colon cancer patients who have received first-line treatment. Although immune checkpoint inhibitors (ICIs) have demonstrated durable clinical efficacy in a variety of solid tumors, their response requires an inflammatory tumor microenvironment. However, microsatellite-stable (MSS) colon cancer, which accounts for the majority of colorectal cancers, is a cold tumor that does not respond well to ICIs. Combination regimens open the door to the utility of ICIs in cold tumors. Although combination therapies have shown their advantage even for MSS colon cancer, it remains unclear whether combination therapies show their advantage in patients with pretreated metastatic colon cancer. We report a patient who has achieved complete remission and good tolerance with sintilimab plus bevacizumab and platinum-based chemotherapy after postoperative recurrence. The patient had KRAS mutation and MSS-type colon cancer, and his PD-1+CD8+ and CD3-CD19-CD14+CD16-HLA-DR were both positive. He has achieved a progression-free survival of 43 months and is still being followed up at our center. The above results suggest that this therapeutic regimen is a promising treatment modality for the management of pretreated, MSS-type and KRAS-mutated metastatic colorectal cancer although its application to the general public still needs to be validated in clinical trials.

Constructing and validating a risk model based on neutrophil-related genes for evaluating prognosis and guiding immunotherapy in colon cancer.

BACKGROUND: Colon cancer is one of the most common digestive tract malignancies. Although immunotherapy has brought new hope to colon cancer patients, there is still a large proportion of patients who do not benefit from immunotherapy. Studies have shown that neutrophils can interact with immune cells and immune factors to affect the prognosis of patients. METHODS: We first determined the infiltration level of neutrophils in tumors using the CIBERSORT algorithm and identified key genes in the final risk model by Spearman correlation analysis and subsequent Cox analysis. The risk score of each patient was obtained by multiplying the Cox regression coefficient and the gene expression level, and patients were divided into two groups based on the median of risk score. Differences in overall survival (OS) and progression-free survival (PFS) were assessed by Kaplan-Meier survival analysis, and model accuracy was validated in independent dataset. Differences in immune infiltration and immunotherapy were evaluated by immunoassay. Finally, immunohistochemistry and western blotting were performed to verify the expression of the three genes in the colon normal and tumor tissues. RESULTS: We established and validated a risk scoring model based on neutrophil-related genes in two independent datasets, The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) database, with SLC11A1 and SLC2A3 as risk factors and MMP3 as a protective factor. A new nomogram was constructed and validated by combining clinical characteristics and the risk score model to better predict patients OS and PFS. Immune analysis showed that patients in the high-risk group had immune cell infiltration level, immune checkpoint level and tumor mutational burden, and were more likely to benefit from immunotherapy. CONCLUSIONS: The low-risk group showed better OS and PFS than the high-risk group in the neutrophil-related gene-based risk model. Patients in the high-risk group presented higher immune infiltration levels and tumor mutational burden and thus may be more responsive to immunotherapy.

MGCNSS: miRNA-disease association prediction with multi-layer graph convolution and distance-based negative sample selection strategy.

Identifying disease-associated microRNAs (miRNAs) could help understand the deep mechanism of diseases, which promotes the development of new medicine. Recently, network-based approaches have been widely proposed for inferring the potential associations between miRNAs and diseases. However, these approaches ignore the importance of different relations in meta-paths when learning the embeddings of miRNAs and diseases. Besides, they pay little attention to screening out reliable negative samples which is crucial for improving the prediction accuracy. In this study, we propose a novel approach named MGCNSS with the multi-layer graph convolution and high-quality negative sample selection strategy. Specifically, MGCNSS first constructs a comprehensive heterogeneous network by integrating miRNA and disease similarity networks coupled with their known association relationships. Then, we employ the multi-layer graph convolution to automatically capture the meta-path relations with different lengths in the heterogeneous network and learn the discriminative representations of miRNAs and diseases. After that, MGCNSS establishes a highly reliable negative sample set from the unlabeled sample set with the negative distance-based sample selection strategy. Finally, we train MGCNSS under an unsupervised learning manner and predict the potential associations between miRNAs and diseases. The experimental results fully demonstrate that MGCNSS outperforms all baseline methods on both balanced and imbalanced datasets. More importantly, we conduct case studies on colon neoplasms and esophageal neoplasms, further confirming the ability of MGCNSS to detect potential candidate miRNAs. The source code is publicly available on GitHub https://github.com/15136943622/MGCNSS/tree/master.

The Construction of a Multi-Gene Risk Model for Colon Cancer Prognosis and Drug Treatments Prediction.

In clinical practice, colon cancer is a prevalent malignant tumor of the digestive system, characterized by a complex and progressive process involving multiple genes and molecular pathways. Historically, research efforts have primarily focused on investigating individual genes; however, our current study aims to explore the collective impact of multiple genes on colon cancer and to identify potential therapeutic targets associated with these genes. For this research, we acquired the gene expression profiles and RNA sequencing data of colon cancer from TCGA. Subsequently, we conducted differential gene expression analysis using R, followed by GO and KEGG pathway enrichment analyses. To construct a protein-protein interaction (PPI) network, we selected survival-related genes using the log-rank test and single-factor Cox regression analysis. Additionally, we performed LASSO regression analysis, immune infiltration analysis, mutation analysis, and cMAP analysis, as well as an investigation into ferroptosis. Our differential expression and survival analyses identified 47 hub genes, and subsequent LASSO regression analysis refined the focus to 23 key genes. These genes are closely linked to cancer metastasis, proliferation, apoptosis, cell cycle regulation, signal transduction, cancer microenvironment, immunotherapy, and neurodevelopment. Overall, the hub genes discovered in our study are pivotal in colon cancer and are anticipated to serve as important biological markers for the diagnosis and treatment of the disease.

LRRK2 G2019S Promotes Colon Cancer Potentially via LRRK2-GSDMD Axis-Mediated Gut Inflammation.

Leucine-rich repeat kinase 2 (LRRK2) is a serine-threonine protein kinase belonging to the ROCO protein family. Within the kinase domain of LRRK2, a point mutation known as LRRK2 G2019S has emerged as the most prevalent variant associated with Parkinson's disease. Recent clinical studies have indicated that G2019S carriers have an elevated risk of cancers, including colon cancer. Despite this observation, the underlying mechanisms linking LRRK2 G2019S to colon cancer remain elusive. In this study, employing a colitis-associated cancer (CAC) model and LRRK2 G2019S knock-in (KI) mouse model, we demonstrate that LRRK2 G2019S promotes the pathogenesis of colon cancer, characterized by increased tumor number and size in KI mice. Furthermore, LRRK2 G2019S enhances intestinal epithelial cell proliferation and inflammation within the tumor microenvironment. Mechanistically, KI mice exhibit heightened susceptibility to DSS-induced colitis, with inhibition of LRRK2 kinase activity ameliorating colitis severity and CAC progression. Our investigation also reveals that LRRK2 G2019S promotes inflammasome activation and exacerbates gut epithelium necrosis in the colitis model. Notably, GSDMD inhibitors attenuate colitis in LRRK2 G2019S KI mice. Taken together, our findings offer experimental evidence indicating that the gain-of-kinase activity in LRRK2 promotes colorectal tumorigenesis, suggesting LRRK2 as a potential therapeutic target in colon cancer patients exhibiting hyper LRRK2 kinase activity.

[Astragali Radix-Curcumae Rhizoma inhibits colon cancer progression and enhances 5-FU efficacy by regulating hypoxia-inducible factors and tumor stem cells].

The animal and cell models were used in this study to investigate the mechanism of Astragali Radix-Curcumae Rhizoma(HQEZ) in inhibiting colon cancer progression and enhancing the efficacy of 5-fluorouracil(5-FU) by regulating hypoxia-inducible factors and tumor stem cells. The animal model was established by subcutaneous transplantation of colon cancer HCT116 cells in nude mice, and 24 successfully modeled mice were randomized into model, 5-FU, HQEZ, and 5-FU+HQEZ groups. The tumor volume was measured every two days. Western blot was employed to measure the protein levels of epidermal growth factor receptor(EGFR), dihydropyrimidine dehydrogenase(DPYD), and thymidylate synthase(TYMS), the key targets of the hypoxic core region, as well as the hypoxia-inducible factors HIF-1α and HIF-2α and the cancer stem cell surface marker CD133 and SRY-box transcription factor 2(SOX2). The results of animal experiments showed that HQEZ slowed down the tumor growth and significantly increased the tumor inhibition rate of 5-FU. Compared with the model group, HQEZ significantly down-regulated the protein levels of EGFR and DPYD, and 5-FU+HQEZ significantly down-regulated the protein levels of EGFR and TYMS in tumors. Compared with the model group, HQEZ significantly down-regulated the protein levels of HIF-1α, HIF-2α, SOX2, and CD133 in the hypoxic core region. Compared with the 5-FU group, 5-FU+HQEZ lowered the protein levels of HIF-1α, HIF-2α, and SOX2. The cell experiments showed that the protein le-vels of HIF-1α and HIF-2α in HCT116 cells elevated significantly after low oxygen treatment. Compared with 5-FU(1.38 µmol·L~(-1)) alone, HQEZ(40 mg·mL~(-1)) and 5-FU+HQEZ significantly down-regulated the protein levels of HIF-1α, HIF-2α, and TYMS. In conclusion, HQEZ can inhibit the expression of hypoxia-responsive molecules in colon cancer cells and reduce the properties of cancer stem cells, thereby enhancing the therapeutic effect of 5-FU on colon cancer.

[Expression of immune checkpoints PD-L1, CTLA4, LAG3 in the microenvironment of colon adenocarcinoma depending on MMR status]. / Ekspressiya immunnykh kontrol'nykh tochek PD-L1, CTLA4, LAG3 v mikrookruzhenii adenokartsinomy tolstoi kishki v zavisimosti ot MMR-statusa.

OBJECTIVE: Study of the features of expression of immune checkpoint proteins PD-L1, CTLA4 and LAG3 in the microenvironment of colon adenocarcinoma depending on MMR status. MATERIAL AND METHODS: The study group consisted of 32 patients with a morphologically confirmed diagnosis of colon cancer; all of them underwent surgical treatment in the form of hemicolonectomy or resection. The work assessed samples of tumor tissue obtained as a result of surgery, the study was carried out in 3 stages: morphological examination of histological slides of colon tumors at the light-optical level, immunohistochemistry examination of tumor samples to determine the dMMR/pMMR status of carcinoma using a panel of antibodies to proteins of the unpaired nucleotide repair system MLH1, MSH2, MSH6 and PMS2, multiplex analysis of PD-L1, CTLA4, LAG3, CD3+, CD8+, CD163+ markers using the Vectra 3.0.3 tissue scanning system (Perkin Elmer, USA). RESULTS: Significant differences in the expression of PD-L1, CTLA4, LAG3 in the area of the invasive tumor margin were revealed between the dMMR and pMMR groups of colon adenocarcinomas in patients comparable in clinical and morphological characteristics and treatment. In the group of tumors with dMMR status, an increase in the expression of all studied markers was noted. The number of CD3+ TILs was also significantly higher in the invasive margin of tumors with dMMR status. Similarly, in this group of colon carcinomas, a large number of CD163+ macrophages were noted both in the center and in the invasive margin zone. No statistically significant differences were found in the expression of immune checkpoints and the composition of TILs in the central zone of tumors with different MMR status. CONCLUSION: A study using multiplex immunohistochemical analysis showed that MMR-deficient colon adenocarcinomas are characterized by more pronounced immune infiltration and increased expression of immune checkpoints in microenvironmental cells, mainly in the area of invasive tumor growth. The data obtained may be important for understanding the mechanisms of immune-mediated control of tumor growth and the choice of immunotherapy tactics depending on MMR status.

Wnt, glucocorticoid and cellular prion protein cooperate to drive a mesenchymal phenotype with poor prognosis in colon cancer.

BACKGROUND: The mesenchymal subtype of colorectal cancer (CRC), associated with poor prognosis, is characterized by abundant expression of the cellular prion protein PrPC, which represents a candidate therapeutic target. How PrPC is induced in CRC remains elusive. This study aims to elucidate the signaling pathways governing PrPC expression and to shed light on the gene regulatory networks linked to PrPC. METHODS: We performed in silico analyses on diverse datasets of in vitro, ex vivo and in vivo models of mouse CRC and patient cohorts. We mined ChIPseq studies and performed promoter analysis. CRC cell lines were manipulated through genetic and pharmacological approaches. We created mice combining conditional inactivation of Apc in intestinal epithelial cells and overexpression of the human prion protein gene PRNP. Bio-informatic analyses were carried out in two randomized control trials totalizing over 3000 CRC patients. RESULTS: In silico analyses combined with cell-based assays identified the Wnt-ß-catenin and glucocorticoid pathways as upstream regulators of PRNP expression, with subtle differences between mouse and human. We uncover multiple feedback loops between PrPC and these two pathways, which translate into an aggravation of CRC pathogenesis in mouse. In stage III CRC patients, the signature defined by PRNP-CTNNB1-NR3C1, encoding PrPC, ß-catenin and the glucocorticoid receptor respectively, is overrepresented in the poor-prognosis, mesenchymal subtype and associates with reduced time to recurrence. CONCLUSIONS: An unleashed PrPC-dependent vicious circle is pathognomonic of poor prognosis, mesenchymal CRC. Patients from this aggressive subtype of CRC may benefit from therapies targeting the PRNP-CTNNB1-NR3C1 axis.

A phenotypic screening approach to target p60AmotL2-expressing invasive cancer cells.

BACKGROUND: Tumor cells have the ability to invade and form small clusters that protrude into adjacent tissues, a phenomenon that is frequently observed at the periphery of a tumor as it expands into healthy tissues. The presence of these clusters is linked to poor prognosis and has proven challenging to treat using conventional therapies. We previously reported that p60AmotL2 expression is localized to invasive colon and breast cancer cells. In vitro, p60AmotL2 promotes epithelial cell invasion by negatively impacting E-cadherin/AmotL2-related mechanotransduction. METHODS: Using epithelial cells transfected with inducible p60AmotL2, we employed a phenotypic drug screening approach to find compounds that specifically target invasive cells. The phenotypic screen was performed by treating cells for 72 h with a library of compounds with known antitumor activities in a dose-dependent manner. After assessing cell viability using CellTiter-Glo, drug sensitivity scores for each compound were calculated. Candidate hit compounds with a higher drug sensitivity score for p60AmotL2-expressing cells were then validated on lung and colon cell models, both in 2D and in 3D, and on colon cancer patient-derived organoids. Nascent RNA sequencing was performed after BET inhibition to analyse BET-dependent pathways in p60AmotL2-expressing cells. RESULTS: We identified 60 compounds that selectively targeted p60AmotL2-expressing cells. Intriguingly, these compounds were classified into two major categories: Epidermal Growth Factor Receptor (EGFR) inhibitors and Bromodomain and Extra-Terminal motif (BET) inhibitors. The latter consistently demonstrated antitumor activity in human cancer cell models, as well as in organoids derived from colon cancer patients. BET inhibition led to a shift towards the upregulation of pro-apoptotic pathways specifically in p60AmotL2-expressing cells. CONCLUSIONS: BET inhibitors specifically target p60AmotL2-expressing invasive cancer cells, likely by exploiting differences in chromatin accessibility, leading to cell death. Additionally, our findings support the use of this phenotypic strategy to discover novel compounds that can exploit vulnerabilities and specifically target invasive cancer cells.

Construction and verification of a histone deacetylases-related prognostic signature model for colon cancer.

Histone deacetylases (HDACs) contribute significantly to the initiation, progression, and prognosis of colorectal adenocarcinoma (COAD). Additionally, HDACs regulate the tumor microenvironment, immune escape, and tumor stem cells, and are closely linked to COAD prognosis. We developed a prognostic model for COAD that incorporates HDACs to evaluate their specific roles. The COAD dataset containing clinical and mutation data was collected using the TCGA and GEO databases to obtain genes associated with HDAC. LASSO analysis and univariate and multivariate Cox regression analysis were used to determine the presence of prognostic genes. Multivariate Cox analysis was also used to determine risk scores for HDAC-related features. Furthermore, genomic alterations, immune infiltration, and drug response were compared between high- and low-risk groups. Cellular experiments validated the potential regulatory role of BRD3 on COAD proliferation, migration, and apoptosis. The median risk scores, calculated based on the characteristics, demonstrated a more significant prognostic improvement in patients in the low-risk group. Furthermore, HDAC-related features were identified as important independent prognostic factors for patients with COAD. Additionally, genomic mutation status, immune infiltration, and function, as well as response to immunotherapy and chemotherapy, were found to be associated with risk scores. Subgroup analyses indicate that anti-PD-1 therapy may be beneficial for patients in the low-risk group. Additionally, a decrease in risk score was associated with a decrease in immune infiltration. Finally, HCT116 and HT29 cells exhibited inhibition of BRD3 gene proliferation and migration, as well as promotion of apoptosis. In patients with COAD, HDAC-related characteristics may be useful in predicting survival and selecting treatment.

The RNA-binding protein RBMS3 inhibits the progression of colon cancer by regulating the stability of LIMS1 mRNA.

BACKGROUND: The RNA-binding motif single-stranded interacting protein 3 (RBMS3) is a constituent of the RNA-binding motif (RBM) protein family, which assumes a pivotal role in governing cellular biogenesis processes such as the cell cycle and apoptosis. Despite an abundance of studies elucidating RBMS3's divergent roles in the genesis and advancement of various tumors, its involvement in colon cancer remains enigmatic. METHODS: The present investigation employed data analysis from TCGA and GTEx to unveil that RBMS3 expression demonstrated a diminished presence in colon cancer tissues when juxtaposed with normal colon tissues. The effect of RBMS3 and LIM zinc finger domain 1 (LIMS1) on colon cancer was substantiated via animal models and cellular experiments. The connection between RBMS3 and LIM zinc finger domain 1 (LIMS1) was verified by molecular biology methods. RESULTS: The study conclusively ascertained that augmenting RBMS3 expression quells the proliferation, migration, and invasion of colon cancer cells. Furthermore, the inquiry unveiled a plausible mechanism through which RBMS3 impacts the expression of LIMS1 by modulating its mRNA stability. The investigation ascertained that RBMS3 inhibits the progression of colon cancer by regulating LIMS1. The inhibitory function of LIMS1 and RBMS3 is closely intertwined in colon cancer, with knocking down LIMS1 being able to rescue the inhibitory effect of RBMS3 overexpression on the functionality of colon cancer cell CONCLUSIONS: The discernments delineate RBMS3 as a novel suppressor of cancer via LIMS1, thereby bestowing fresh therapeutic possibilities and illuminating the intricacies of colon cancer.

New treatment alternatives for primary and metastatic colorectal cancer by an integrated transcriptome and network analyses.

Metastatic colorectal cancer (CRC) is still in need of effective treatments. This study applies a holistic approach to propose new targets for treatment of primary and liver metastatic CRC and investigates their therapeutic potential in-vitro. An integrative analysis of primary and metastatic CRC samples was implemented for alternative target and treatment proposals. Integrated microarray samples were grouped based on a co-expression network analysis. Significant gene modules correlated with primary CRC and metastatic phenotypes were identified. Network clustering and pathway enrichments were applied to gene modules to prioritize potential targets, which were shortlisted by independent validation. Finally, drug-target interaction search led to three agents for primary and liver metastatic CRC phenotypes. Hesperadin and BAY-1217389 suppress colony formation over a 14-day period, with Hesperadin showing additional efficacy in reducing cell viability within 48 h. As both candidates target the G2/M phase proteins NEK2 or TTK, we confirmed their anti-proliferative properties by Ki-67 staining. Hesperadinin particular arrested the cell cycle at the G2/M phase. IL-29A treatment reduced migration and invasion capacities of TGF-ß induced metastatic cell lines. In addition, this anti-metastatic treatment attenuated TGF-ß dependent mesenchymal transition. Network analysis suggests IL-29A induces the JAK/STAT pathway in a preventive manner.

α­Phellandrene enhances the apoptosis of HT­29 cells induced by 5­fluorouracil by modulating the mitochondria­dependent pathway.

α­Phellandrene (α­PA), a natural constituent of herbs, inhibits cancer cell viability and proliferation. 5­Fluorouracil (5­FU) is a frequently utilized chemotherapeutic medicine for the treatment of colon cancer, which works by triggering cancer cell apoptosis. The present study examined how the combination of α­PA and 5­FU affects the suppression of human colon cancer cells by promoting apoptosis. The impact of this treatment on cell viability, apoptosis, and the expression levels of Bcl­2 family members, caspase family members and mitochondria­related molecules in HT­29 cells was assessed by the MTT assay, immunocytochemistry, western blotting and quantitative PCR. The combination of 5­FU and α­PA had a synergistic inhibitory effect on cell viability, as determined by assessing the combination index value. Bax protein expression levels were higher in the 50, 100 or 250 µM α­PA combined with 5­FU groups compared with those in the 5­FU alone group (P<0.05). By contrast, Bcl­2 protein expression levels and mitochondrial membrane potential (MMP, ΔΨm) were lower in the 100 or 250 µM α­PA combined with 5­FU groups than those in the 5­FU alone group (P<0.05). In addition, hexokinase­2 (HK­2) protein expression levels were lower in the 50, 100 or 250 µM α­PA combined with 5­FU groups than those in the 5­FU alone group (P<0.05). Compared with 5­FU alone, after HT­29 cells were treated with 50, 100 or 250 µM α­PA combined with 5­FU, the mRNA expression levels of extrinsic­induced apoptotic molecules, including caspase­8 and Bid, were higher (P<0.05). Treatment with 50, 100 or 250 µM α­PA combined with 5­FU also increased the mRNA expression levels of cytochrome c, caspase­9 and caspase­3, regulating intrinsic apoptosis (P<0.05). These results showed that α­PA and 5­FU had a synergistic effect on reducing the viability of human colon cancer HT­29 cells by inducing extrinsic and intrinsic apoptosis pathways. The mechanism by which apoptosis is induced may involve the intrinsic apoptosis pathway that activates the mitochondria­dependent pathway, including regulating the expression levels of Bcl­2 family members, including Bax, Bcl­2 and Bid, regulating MMP and HK­2 expression levels, and increasing the expression of caspase cascade molecules, including caspase­9 and caspase­3. In addition, it may involve the extrinsic apoptosis pathway that activates caspase­8 and caspase­3 leading to apoptosis.

Ionizable Lipid Nanoparticle-Mediated TRAIL mRNA Delivery in the Tumor Microenvironment to Inhibit Colon Cancer Progression.

Introduction: Immunotherapy has revolutionized cancer treatment by harnessing the immune system to enhance antitumor responses while minimizing off-target effects. Among the promising cancer-specific therapies, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has attracted significant attention. Methods: Here, we developed an ionizable lipid nanoparticle (LNP) platform to deliver TRAIL mRNA (LNP-TRAIL) directly to the tumor microenvironment (TME) to induce tumor cell death. Our LNP-TRAIL was formulated via microfluidic mixing and the induction of tumor cell death was assessed in vitro. Next, we investigated the ability of LNP-TRAIL to inhibit colon cancer progression in vivo in combination with a TME normalization approach using Losartan (Los) or angiotensin 1-7 (Ang(1-7)) to reduce vascular compression and deposition of extracellular matrix in mice. Results: Our results demonstrated that LNP-TRAIL induced tumor cell death in vitro and effectively inhibited colon cancer progression in vivo, particularly when combined with TME normalization induced by treatment Los or Ang(1-7). In addition, potent tumor cell death as well as enhanced apoptosis and necrosis was found in the tumor tissue of a group treated with LNP-TRAIL combined with TME normalization. Discussion: Together, our data demonstrate the potential of the LNP to deliver TRAIL mRNA to the TME and to induce tumor cell death, especially when combined with TME normalization. Therefore, these findings provide important insights for the development of novel therapeutic strategies for the immunotherapy of solid tumors.

PANoptosis-related genes function as efficient prognostic biomarkers in colon adenocarcinoma.

Background: PANoptosis is a newly discovered cell death type, and tightly associated with immune system activities. To date, the mechanism, regulation and application of PANoptosis in tumor is largely unknown. Our aim is to explore the prognostic value of PANoptosis-related genes in colon adenocarcinoma (COAD). Methods: Analyzing data from The Cancer Genome Atlas-COAD (TCGA-COAD) involving 458 COAD cases, we concentrated on five PANoptosis pathways from the Molecular Signatures Database (MSigDB) and a comprehensive set of immune-related genes. Our approach involved identifying distinct genetic COAD subtype clusters and developing a prognostic model based on these parameters. Results: The research successfully identified two genetic subtype clusters in COAD, marked by distinct profiles in PANoptosis pathways and immune-related gene expression. A prognostic model, incorporating these findings, demonstrated significant predictive power for survival outcomes, underscoring the interplay between PANoptosis and immune responses in COAD. Conclusion: This study enhances our understanding of COAD's genetic framework, emphasizing the synergy between cell death pathways and the immune system. The development of a prognostic model based on these insights offers a promising tool for personalized treatment strategies. Future research should focus on validating and refining this model in clinical settings to optimize therapeutic interventions in COAD.

Deubiquitinase BRCC3 promotes the migration, invasion and EMT progression of colon adenocarcinoma by stabilizing MET expression.

BACKGROUND: Breast cancer type 1 susceptibility protein/breast cancer type 2 susceptibility protein-containing complex subunit 3 (BRCC3), a deubiquitinase (DUBs), is overexpressed in various cancers. However, the underlying biological roles of BRCC3 in adenocarcinoma colon (COAD) have yet to be decrypted. OBJECTIVE: In this work, we explored the potential biological function of BRCC3 in the natural process of COAD cells. METHODS: The expression levels of BRCC3 in COAD tissues and cell lines were investigated via quantitative real time polymerase chain reaction and western blotting analyses. Meanwhile, short hairpin RNAs targeting BRCC3 (sh-BRCC3) or mesenchymal-epithelial transition factor (MET) (sh-MET) were used to investigate the biological function, including proliferation, apoptosis, migration, invasion, and epithelial-mesenchymal transition (EMT) progression in COAD cells. Furthermore, the expression levels of EMT-related biomarkers were detected with western blotting analysis. Furthermore, we also performed Co-IP assay to identify the correlation between BRCC3 and MET. RESULTS: BRCC3 expression was increased in COAD tissues and cell lines. ShRNA-mediated downmodulation of BRCC3 in COAD cell lines induced EMT progression. BRCC3 knockdown resulted in decreased migration as well as invasion and increased apoptosis of SW480 and Lovo cells. Besides, MET was regulated by BRCC3 and involved in the migration, invasion, and EMT in SW480 and Lovo cells. Finally, we uncovered that the overexpressed MET reversed the effects of BRCC3 knockdown in COAD cell development. CONCLUSIONS: BRCC3 acted as a critical factor in the development of COAD by deubiquitinating and stabilizing MET, which might provide an emerging biomarker for the therapeutic and diagnosis strategy of COAD.

Select EZH2 inhibitors enhance viral mimicry effects of DNMT inhibition through a mechanism involving NFAT:AP-1 signaling.

DNA methyltransferase inhibitor (DNMTi) efficacy in solid tumors is limited. Colon cancer cells exposed to DNMTi accumulate lysine-27 trimethylation on histone H3 (H3K27me3). We propose this Enhancer of Zeste Homolog 2 (EZH2)-dependent repressive modification limits DNMTi efficacy. Here, we show that low-dose DNMTi treatment sensitizes colon cancer cells to select EZH2 inhibitors (EZH2is). Integrative epigenomic analysis reveals that DNMTi-induced H3K27me3 accumulates at genomic regions poised with EZH2. Notably, combined EZH2i and DNMTi alters the epigenomic landscape to transcriptionally up-regulate the calcium-induced nuclear factor of activated T cells (NFAT):activating protein 1 (AP-1) signaling pathway. Blocking this pathway limits transcriptional activating effects of these drugs, including transposable element and innate immune response gene expression involved in viral defense. Analysis of primary human colon cancer specimens reveals positive correlations between DNMTi-, innate immune response-, and calcium signaling-associated transcription profiles. Collectively, we show that compensatory EZH2 activity limits DNMTi efficacy in colon cancer and link NFAT:AP-1 signaling to epigenetic therapy-induced viral mimicry.

Cinobufotalin regulates the USP36/c-Myc axis to suppress malignant phenotypes of colon cancer cells in vitro and in vivo.

Ubiquitin-specific protease 36 (USP36) has been reported to exhibit oncogenic effects in various malignancies, but the function of USP36 in colon cancer progression remains indefinite. Herein, we aimed to determine the role and mechanism of USP36 in malignant phenotypes of colon cancer cells and explore the potential drug targeting USP36. Bioinformatics analyses indicated that USP36 is highly expressed and significantly related to tumor stages in colon cancer. Besides, USP36 was further up-regulated in oxaliplatin (Oxa)-resistant colon cancer cells. Colony formation, Edu staining, Transwell, wound healing, sphere formation, and CCK-8 assays were conducted and showed that the proliferation, Oxa-resistance, migration, stemness, and invasion of HCT116 cells were promoted after overexpressing USP36, while suppressed by USP36 knockdown. Mechanically, USP36 enhances c-Myc protein stabilization in HCT116 cells via deubiquitination. AutoDock tool and ubiquitin-AMC hydrolysis assay identified cinobufotalin (CBF), an anti-tumor drug, maybe a USP36 inhibitor by inhibiting its deubiquitination activity. CBF significantly prohibited proliferation, migration, invasion, and stemness of HCT116 cells and reversed Oxa-resistance, whereas enforced expression of USP36 blocked these effects. Moreover, in vivo analyses confirmed the oncogenic role of USP36 and the therapeutic potential of CBF in the malignancy of colon cancer. In conclusion, CBF may be a promising therapeutic agent for colon cancer due to its regulation of the USP36/c-Myc axis.

A Novel DNA Variant in SMARCA4 Gene Found in a Patient Affected by Early Onset Colon Cancer.

Colorectal cancer is the third leading cause of death from neoplasia worldwide. Thanks to new screening programs, we are now seeing an increase in Early Onset of ColoRectal Cancer (EOCRC) in patients below the age of 50. Herein, we report a clinical case of a woman affected by EOCRC. This case illustrates the importance of genetic predisposition testing also in tumor patients. Indeed, for our patient, we used a combined approach of multiple molecular and cellular biology technologies that revealed the presence of an interesting novel variant in the SMARCA4 gene. The latter gene is implicated in damage repair processes and related, if mutated, to the onset of various tumor types. In addition, we stabilized Patient-Derived Organoids from the tumor tissue of the same patient and the result confirmed the presence of this novel pathogenic variant that has never been found before even in early onset cancer. In conclusion, with this clinical case, we want to underscore the importance of including patients even those below the age of 50 years in appropriate screening programs which should also include genetic tests for predisposition to early onset cancers.

Casein kinase 2 phosphorylates and induces the SALL2 tumor suppressor degradation in colon cancer cells.

Spalt-like proteins are Zinc finger transcription factors from Caenorhabditis elegans to vertebrates, with critical roles in development. In vertebrates, four paralogues have been identified (SALL1-4), and SALL2 is the family's most dissimilar member. SALL2 is required during brain and eye development. It is downregulated in cancer and acts as a tumor suppressor, promoting cell cycle arrest and cell death. Despite its critical functions, information about SALL2 regulation is scarce. Public data indicate that SALL2 is ubiquitinated and phosphorylated in several residues along the protein, but the mechanisms, biological consequences, and enzymes responsible for these modifications remain unknown. Bioinformatic analyses identified several putative phosphorylation sites for Casein Kinase II (CK2) located within a highly conserved C-terminal PEST degradation motif of SALL2. CK2 is a serine/threonine kinase that promotes cell proliferation and survival and is often hyperactivated in cancer. We demonstrated that CK2 phosphorylates SALL2 residues S763, T778, S802, and S806 and promotes SALL2 degradation by the proteasome. Accordingly, pharmacological inhibition of CK2 with Silmitasertib (CX-4945) restored endogenous SALL2 protein levels in SALL2-deficient breast MDA-MB-231, lung H1299, and colon SW480 cancer cells. Silmitasertib induced a methuosis-like phenotype and cell death in SW480 cells. However, the phenotype was significantly attenuated in CRISPr/Cas9-mediated SALL2 knockout SW480 cells. Similarly, Sall2-deficient tumor organoids were more resistant to Silmitasertib-induced cell death, confirming that SALL2 sensitizes cancer cells to CK2 inhibition. We identified a novel CK2-dependent mechanism for SALL2 regulation and provided new insights into the interplay between these two proteins and their role in cell survival and proliferation.