The therapeutic and prognostic implications of immunobiology in colorectal cancer: a review

Prognostic significance of negative lymph node count in microsatellite instability-high colorectal cancer

BACKGROUND

Microsatellite instability-high (MSI-H) tumors, with elevated tumor mutational burden and expression of neoantigens, represent a distinct immune-activated subpopulation in colorectal cancer (CRC), characterized by strong lymph node reaction, locally advanced tumor and higher total lymph nodes harvested (TLN), but less metastatic lymph nodes and fewer incidence of III-IV stage. Host immune response to tumor and lymph nodes may be an important prognostic factor. However, N stage and LNR (Lymph-Node Ratio) have limitations in predicting the prognosis of MSI-H patients. Negative lymph node count (NLC) provided a more precise representation of immune activation status and extent of tumor metastasis. The study aims to detect prognostic significance of NLC in MSI-H CRC patients, and compare it with N stage, TLN and LNR.

METHODS

Retrospective data of 190 consecutive MSI-H CRC patients who received curative resection were collected. Survival analyses were performed using the Kaplan-Meier method. Clinicopathological variables including NLC, N stage, TLN and LNR were studied in univariate and multivariate COX regression analyses. ROC (receiver operating characteristic curve) and concordance index were employed to compare the differences in predictive efficacy between NLC, N stage, TLN and LNR.

RESULTS

Patients with increased NLC experienced a significantly improved 5-years DFS and OS in Kaplan-Meier analysis, univariate analysis, and multivariate analysis, independent of potential confounders examined. Increased NLC corresponded to elevated 5-years DFS rate and 5-years OS rate. AUC (area under curve) and concordance index of NLC in DFS and OS predicting were both significantly higher than N stage, TLN and LNR.

CONCLUSIONS

Negative lymph node is an important independent prognostic factor for MSI-H patients. Reduced NLC is associated with tumor recurrence and poor survival, which is a stronger prognostic factor than N stage, TLN and LNR.

Genomic and Transcriptomic Analysis of a Patient with Early-Onset Colorectal Cancer and Therapy-Induced Focal Nodular Hyperplasia: A Case Report

Early-onset colorectal cancer (EOCRC), defined as colorectal cancer in individuals under 50 years of age, has shown an alarming increase in incidence worldwide. We report a case of a twenty-four-year-old female with a strong family history of colorectal cancer (CRC) but without an identified underlying genetic predisposition syndrome. Two years after primary surgery and adjuvant chemotherapy, the patient developed new liver lesions. Extensive diagnostic imaging was conducted to investigate suspected liver metastases, ultimately leading to a diagnosis of focal nodular hyperplasia. The young age of the patient has prompted comprehensive genomic and transcriptomic profiling in order to identify potential oncogenic drivers and inform further clinical management of the patient. Besides a number of oncogenic mutations identified in the patient's tumour sample, including KRAS G12D, TP53 R248W and TTN L28470V, we have also identified a homozygous deletion of 24.5 MB on chromosome 8. A multivariate Cox regression analysis of this patient's mutation profile conferred a favourable prognosis when compared with the TCGA COADREAD database. Notably, the identified deletion on chromosome 8 includes the WRN gene, which could contribute to the patient's overall positive response to chemotherapy. The complex clinical presentation, including the need for emergency surgery, early age at diagnosis, strong family history, and unexpected findings on surveillance imaging, necessitated a multidisciplinary approach involving medical, radiation, and surgical oncologists, along with psychological support and reproductive medicine specialists. Molecular profiling of the tumour strongly indicates that patients with complex mutational profile and rare genomic rearrangements require a prolonged surveillance and personalised informed interventions.

High Expression Level of TRIP6 is Correlated with Poor Prognosis in Colorectal Cancer and Promotes Tumor Cell Proliferation and Migration

Globally, colorectal cancer (CRC) is one of the leading causes of health problems. More reliable molecular biomarkers for early diagnosis in CRC patients are needed. A crucial role for thyroid hormone receptor interacting protein 6 (TRIP6) is played in tumorigenesis and tumor growth. Our study aims to determine the diagnostic and prognostic roles of TRIP6 at CRC. TRIP6 gene expression levels were analyzed in this study from public databases. The relationship between TRIP6 expression and clinicopathological characteristics was explored by logistic regression analysis. Based on Kaplan-Meier (K-M) survival curves and receiver operating characteristic curves (ROC) analysis, the prognostic and diagnostic values of TRIP6 were determined. Protein-protein interaction (PPI) networks analysis were performed using the STRING database. A Spearman's correlation analysis applied for examining the correlation between TRIP6 expression, immune cell infiltration, and immune checkpoint genes. Moreover, colony formation assay and transwell assay were used to investigate the functions of TRIP6. TRIP6 was highly expressed in CRC cancer tissues and cells. K-M survival analysis indicated that a high expression of TRIP6 was associated with poor prognosis. TRIP6 expression was obviously associated with immune cell infiltration and immune checkpoint gene expression. For validation, the results of collected clinical CRC samples show that TRIP6 levels in CRC tumor tissue were higher than those of paired adjacent colorectal tissues. Additionally, in vitro experiments suggested that TRIP6 knockdown suppressed proliferation and migration in CRC cell line RKO. TRIP6 overexpression promoted the proliferation and migration of normal colon cell line NCM460. High TRIP6 expression is associated with poor prognosis in colorectal cancer and promotes tumor cell proliferation and migration which may be a potential diagnostic and prognostic biomarker and a promising therapeutic target for CRC, providing new insights into its role in CRC.

An Analysis Regarding the Association Between DAZ Interacting Zinc Finger Protein 1 (DZIP1) and Colorectal Cancer (CRC)

Colorectal cancer (CRC) is the third most common malignant disease worldwide, and its incidence is increasing, but the molecular mechanisms of this disease are highly heterogeneous and still far from being fully understood. Increasing evidence suggests that fibrosis mediated by abnormal activation of fibroblasts based in the microenvironment is associated with a poor prognosis. However, the function and pathogenic mechanisms of fibroblasts in CRC remain unclear. Here, combining scrna-seq and clinical specimen data, DAZ Interacting Protein 1 (DZIP1) was found to be expressed on fibroblasts and cancer cells and positively correlated with stromal deposition. Importantly, pseudotime-series analysis showed that DZIP1 levels were up-regulated in malignant transformation of fibroblasts and experimentally confirmed that DZIP1 modulates activation of fibroblasts and promotes epithelial-mesenchymal transition (EMT) in tumor cells. Further studies showed that DZIP1 expressed by tumor cells also has a driving effect on EMT and contributes to the recruitment of more fibroblasts. A similar phenomenon was observed in xenografted nude mice. And it was confirmed in xenograft mice that downregulation of DZIP1 expression significantly delayed tumor formation and reduced tumor size in CRC cells. Taken together, our findings suggested that DZIP1 was a regulator of the CRC mesenchymal phenotype. The revelation of targeting DZIP1 provides a new avenue for CRC therapy.

Spatial transcriptomic analysis reveals local effects of intratumoral fusobacterial infection on DNA damage and immune signaling in rectal cancer

Mucinous colorectal cancer (CRC) is a common histological subtype of colorectal adenocarcinoma, associated with a poor response to chemoradiotherapy. The commensal facultative anaerobes fusobacteria, have been associated with poor prognosis specifically in mesenchymal CRC. Interestingly, fusobacterial infection is especially prevalent in mucinous CRC. The objective of this study was therefore to increase our understanding of beneficial and detrimental effects of fusobacterial infection, by contrasting host cell signaling and immune responses in areas of high vs. low infection, using mucinous rectal cancer as a clinically relevant example. We employed spatial transcriptomic profiling of 106 regions of interest from 8 mucinous rectal cancer samples to study gene expression in the epithelial and immune segments across regions of high versus low fusobacterial infection. Fusobacteria high regions were associated with increased oxidative stress, DNA damage, and P53 signaling. Meanwhile regions of low fusobacterial prevalence were characterized by elevated JAK-STAT, Il-17, Il-1, chemokine and TNF signaling. Immune masks within fusobacterial high regions were characterized by elevated proportions of cytotoxic (CD8+) T cells (p = 0.037), natural killer (NK) cells (p < 0.001), B-cells (p < 0.001), and gamma delta T cells (p = 0.003). Meanwhile, fusobacteria low regions were associated with significantly greater M2 macrophage (p < 0.001), fibroblast (p < 0.001), pericyte (p = 0.002), and endothelial (p < 0.001) counts.

Less Invasive Primary Treatment for Colorectal Cancer After Implementation of National Screening: A Nationwide Cohort Study

BACKGROUND

The effect of organized colorectal cancer (CRC) screening on type of primary treatment remains sparsely investigated. This study evaluated the difference in primary treatment strategy between patients diagnosed with screen-detected (SD-CRC) and non-screen-detected colorectal cancer (NSD-CRC) in a national CRC screening program.

METHODS

This was a retrospective national register-based cohort study. Data on patients aged between 50 and 75 years and diagnosed with SD-CRC or NSD-CRC were retrieved from the national colorectal cancer screening database and the Danish Colorectal Cancer Group database. Outcomes related to surgical invasiveness were compared between the two cohorts. Differences were expressed as relative risks using log-binomial generalized linear regression models. UICC stage IV specific outcomes were analyzed using the same method. All analyses were adjusted for sex, age, type of cancer (colonic/rectal), and Charlson comorbidity index.

RESULTS

The study included 4707 patients with SD-CRC and 7328 with NSD-CRC. Therapeutic flexible endoscopy (SD-CRC: n = 636 vs. NSD-CRC: n = 334, RR: 2.50, P < 0.001), (robotic-assisted) laparoscopic resection ((n = 616 vs. n = 773, RR: 1.27, P < 0.001), n = 2759 vs. n = 3471, RR: 1.11, P < 0.001), and radical resection (n = 3890 vs. n = 4834, RR: 1.02, P = 0.002) were significantly more frequent in the SD-CRC group. The rates of emergency priority (n = 32 vs. n = 562, RR: 0.09, P < 0.001), open surgery (n = 391 vs. n = 1410, RR: 0.53, P < 0.001), supplementary organ resection (n = 259 vs. n = 860, RR: 0.56, P < 0.001), and stoma formation (n = 526 vs. n = 1040, RR: 0.89, P = 0.007) were significantly lower in the SD-CRC group. The rate of patients undergoing surgery with UICC stage IV disease was significantly higher in the SD-CRC group (SD-CRC: n = 262, NSD-CRC: n = 994, RR: 1.43, P < 0.001).

CONCLUSION

SD-CRC remained associated with less invasive primary surgical treatment following adjustment for potential healthy user bias. UICC stage IV disease may be less advanced in patients with SD-CRC.

A radiomics model fusing clinical features to predict microsatellite status preoperatively in colorectal cancer liver metastasis

PURPOSE

To study the combined model of radiomic features and clinical features based on enhanced CT images for noninvasive evaluation of microsatellite instability (MSI) status in colorectal liver metastasis (CRLM) before surgery.

METHODS

The study included 104 patients retrospectively and collected CT images of patients. We adjusted the region of interest to increase the number of MSI-H images. Radiomic features were extracted from these CT images. The logistic models of simple clinical features, simple radiomic features, and radiomic features with clinical features were constructed from the original image data and the expanded data, respectively. The six models were evaluated in the validation set. A nomogram was made to conveniently show the probability of the patient having a high MSI (MSI-H).

RESULTS

The model including radiomic features and clinical features in the expanded data worked best in the validation group.

CONCLUSION

A logistic regression prediction model based on enhanced CT images combining clinical features and radiomic features after increasing the number of MSI-H images can effectively identify patients with CRLM with MSI-H and low-frequency microsatellite instability (MSI-L), and provide effective guidance for clinical immunotherapy of CRLM patients with unknown MSI status.

Ibero-American Consensus Review and Incorporation of New Biomarkers for Clinical Practice in Colorectal Cancer

Advances in genomic technologies have significantly improved the management of colorectal cancer (CRC). Several biomarkers have been identified in CRC that enable personalization in the use of biologic agents that have shown to enhance the clinical outcomes of patients. However, technologies used for their determination generate massive amounts of information that can be difficult for the clinician to interpret and use adequately. Through several discussion meetings, a group of oncology experts from Spain and several Latin American countries reviewed the latest literature to provide practical recommendations on the determination of biomarkers in CRC based on their clinical experience. The article also describes the importance of looking for additional prognostic biomarkers and the use of histopathology to establish an adequate molecular classification. Present and future of immunotherapy biomarkers in CRC patients are also discussed, together with several techniques for marker determination, including liquid biopsy, next-generation sequencing (NGS), polymerase chain reaction (PCR), and fecal immunohistochemical tests. Finally, the role of Molecular Tumor Boards in the diagnosis and treatment of CRC is described. All of this information will allow us to highlight the importance of biomarker determination in CRC.

A Review of 10-Year Survivability of Immunotherapy in the Management of Colon Cancer

Colon cancer is one of the most common cancers in the United States of America. In addition to conventional treatment approaches such as surgery, chemotherapy, and radiation for colorectal cancer, immunotherapy has gained recognition over the past few years. However, its effectiveness in colorectal cancer treatment is controversial. Our study investigates the survival and progression-free rates of immunotherapy for different types of colorectal cancer over the last 10 years. We conducted literature reviews from various clinical trials and research studies to evaluate immunotherapy's role in colorectal cancer treatment. We also investigated how it affects clinical outcomes. We discovered a range of effective immunotherapy approaches targeting various growth factors and signaling pathways. These modalities include monoclonal antibodies aimed at growth factors such as epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), human epidermal growth factor receptor 2 (HER2), and downstream signaling pathways such as mitogen-activated protein kinase (MAPK), kirsten rat sarcoma viral oncogene (KRAS), B-raf proto-oncogene, serine/threonine kinase (BRAF), and phosphatase and tensin homolog (PTEN). Additionally, we identified immune checkpoint inhibitors, such as cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) inhibitors and programmed cell death ligand 1 (PD-L1) inhibitors, as well as target therapy and adoptive cell therapy as promising immunotherapeutic options. Nevertheless, the application of immunotherapy remains highly limited due to various factors influencing survival and progression-free rates, including tumor microenvironment, microsatellite instability, immune checkpoint expression, and gut microbiome. Additionally, its effectiveness is restricted to a small subgroup of patients, accompanied by side effects and the development of drug resistance mechanisms. To unlock its full potential, further clinical trials and research on molecular pathways in colorectal cancer are imperative. This will ultimately enhance drug discovery success and lead to more effective clinical management approaches.

Garcinone E triggers apoptosis and cell cycle arrest in human colorectal cancer cells by mediating a reactive oxygen species–dependent JNK signaling pathway

Despite various therapeutic approaches, colorectal cancer is among the most fatal diseases globally. Hence, developing novel and more effective methods for colorectal cancer treatment is essential. Recently, reactive oxygen species (ROS)/JNK signaling pathway has been proposed as the potential target for the anticancer drug discovery. The present study investigated the anticancer effects of the bioactive xanthone garcinone E (GAR E) in mangosteen and explored its underlying mechanism of action. HT-29 and Caco-2 cancer cells were used as in vitro models to study the anticancer effect of GAR E. The findings demonstrated that GAR E inhibited colony formation and wound healing, whereas triggered the production of ROS, which induced mitochondrial dysfunction and apoptosis, causing cell cycle arrest at the Sub G1 phase. Additionally, GAR E treatment elevated the ratio of Bax/Bcl-2 and activated PARP, caspases 3 and 9, and JNK1/2. These GAR E-induced cytotoxic activities and expression of signaling proteins were reversed by the antioxidant N-acetyl-L-cysteine and JNK inhibitor SP600125, indicating the involvement of ROS/JNK signaling pathways. In vivo experiments using an HT-29 xenograft nude mouse model also demonstrated the antitumor effect of GAR E. In conclusion, our findings showed that GAR E might be potentially effective in treating colorectal cancer and provided insights into the development of xanthones as novel chemotherapeutic agents.

Combination of immune checkpoint blockade and targeted gene regulation of angiogenesis for facilitating antitumor immunotherapy

The rapid development of tumor immunotherapy has improved the management of patients with cancer. However, several key problems of tumor immunotherapy, including the insufficient activation of effector T cells, poor tumor invasion, and poor immune killing ability, lead to a low response rate. In the present study, a synergistic strategy was developed by combining in situ tumor vaccines, gene-mediated downregulation of tumor angiogenesis, and anti-PD-L1 therapy. In situ tumor vaccines and antitumor angiogenesis were achieved by codelivering unmethylated cytosine-phosphate-guanine (CpG) and vascular endothelial growth factor (VEGF)-silencing gene (shVEGF) via a hyaluronic acid (HA)-modified HA/PEI/shVEGF/CpG system. Necrotic tumor cells and CpG adjuvants formed in situ tumor vaccines and activated the host immune response. Moreover, VEGF silencing reduced tumor angiogenesis and prompted the homogeneous distribution of tumor blood vessels to facilitate immune cell infiltration. Meanwhile, anti-angiogenesis also improved the immunosuppressive tumor microenvironment. To further improve the specific tumor-killing effect, an anti-PD-L1 antibody was introduced for immune checkpoint blockade, thereby boosting antitumor immune responses. The combination therapy strategy presented in the present study could act in the multiple stages of the tumor immunotherapy cycle, which is expected to offer a new avenue for clinical tumor immunotherapy.

Integrated analysis identifies oxidative stress-related lncRNAs associated with progression and prognosis in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is one of the most common cancers in the world. Oxidative stress reactions have been reportedly associated with oncogenesis and tumor progression. By analyzing mRNA expression data and clinical information from The Cancer Genome Atlas (TCGA), we aimed to construct an oxidative stress-related long noncoding RNA (lncRNA) risk model and identify oxidative stress-related biomarkers to improve the prognosis and treatment of CRC.

RESULTS

Differentially expressed oxidative stress-related genes (DEOSGs) and oxidative stress-related lncRNAs were identified by using bioinformatics tools. An oxidative stress-related lncRNA risk model was constructed based on 9 lncRNAs (AC034213.1, AC008124.1, LINC01836, USP30-AS1, AP003555.1, AC083906.3, AC008494.3, AC009549.1, and AP006621.3) by least absolute shrinkage and selection operator (LASSO) analysis. The patients were then divided into high- and low-risk groups based on the median risk score. The high-risk group had a significantly worse overall survival (OS) (p < 0.001). Receiver operating characteristic (ROC) and calibration curves displayed the favorable predictive performance of the risk model. The nomogram successfully quantified the contribution of each metric to survival, and the concordance index and calibration plots demonstrated its excellent predictive capacity. Notably, different risk subgroups showed significant differences in terms of their metabolic activity, mutation landscape, immune microenvironment and drug sensitivity. Specifically, differences in the immune microenvironment implied that CRC patients in certain subgroups might be more responsive to immune checkpoint inhibitors.

CONCLUSIONS

Oxidative stress-related lncRNAs can predict the prognosis of CRC patients, which provides new insight for future immunotherapies based on potential oxidative stress targets.

Transcriptomic and functional analyses reveal a tumour-promoting role for the IL-36 receptor in colon cancer and crosstalk between IL-36 signalling and the IL-17/ IL-23 axis

BACKGROUND

The interleukin (IL)-36 cytokines are a sub-family of the IL-1 family which are becoming increasingly implicated in the pathogenesis of inflammatory diseases and malignancies. Initial studies of IL-36 signalling in tumorigenesis identified an immune-mediated anti-tumorigenic function for these cytokines. However, more recent studies have shown IL-36 cytokines also contribute to the pathogenesis of lung and colorectal cancer (CRC).

METHODS

The aim of this study was to investigate IL-36 expression in CRC using transcriptomic datasets and software such as several R packages, Cytoscape, GEO2R and AnalyzeR. Validation of results was completed by qRT-PCR on both cell lines and a patient cohort. Cellular proliferation was assessed by flow cytometry and resazurin reduction.

RESULTS

We demonstrate that IL-36 gene expression increases with CRC development. Decreased tumoral IL-36 receptor expression was shown to be associated with improved patient outcome. Our differential gene expression analysis revealed a novel role for the IL-36/IL-17/IL-23 axis, with these findings validated using patient-derived samples and cell lines. IL-36γ, together with either IL-17a or IL-22, was able to synergistically induce different genes involved in the IL-17/IL-23 axis in CRC cells and additively induce colon cancer cell proliferation.

CONCLUSIONS

Collectively, this data support a pro-tumorigenic role for IL-36 signalling in colon cancer, with the IL-17/IL-23 axis influential in IL-36-mediated colon tumorigenesis.

Oncotherapeutic Strategies in Early Onset Colorectal Cancer

Early onset colorectal cancer (EOCRC), defined as colorectal cancers in patients aged less than 50 years, is becoming an increasingly common issue, globally. Since 1994, the incidence of this condition has been rising by 2% annually. Approximately one in five patients under 50 years of age diagnosed with colorectal cancer have an underlying genetic predisposition syndrome. The detection of cancer among the other 80% of patients poses a considerable task, as there is no family history to advocate for commencing early screening in this group. Patients with EOCRC have distinct social, spiritual, fertility, and financial needs from their older counterparts that need to be addressed. This review discusses the risk factors associated with the development of EOCRC and current best practice for the management of this disease.

New target DDR1: A "double-edged sword" in solid tumors

Globally, cancer is a major catastrophic disease that seriously threatens human health. Thus, there is an urgent need to find new strategies to treat cancer. Among them, identifying new targets is one of the best ways to treat cancer at present. Especially in recent years, scientists have discovered many new targets and made breakthroughs in the treatment of cancer, bringing new hope to cancer patients. As one of the novel targets for cancer treatment, DDR1 has attracted much attention due to its unique role in cancer. Hence, here, we focus on a new target, DDR1, which may be a "double-edged sword" of human solid tumors. In this review, we provide a comprehensive overview of how DDR1 acts as a "double-edged sword" in cancer. First, we briefly introduce the structure and normal physiological function of DDR1; Second, we delineate the DDR1 expression pattern in single cells; Next, we sorte out the relationship between DDR1 and cancer, including the abnormal expression of DDR1 in cancer, the mechanism of DDR1 and cancer occurrence, and the value of DDR1 on cancer prognosis. In addition, we introduced the current status of global drug and antibody research and development targeting DDR1 and its future design prospects; Finally, we summarize and look forward to designing more DDR1-targeting drugs in the future to make further progress in the treatment of solid tumors.

IL1RN and PRRX1 as a Prognostic Biomarker Correlated with Immune Infiltrates in Colorectal Cancer: Evidence from Bioinformatic Analysis

The extensive morbidity of colorectal cancer (CRC) and the inferior prognosis of terminal CRC urgently call for reliable prognostic biomarkers. For this, we identified 704 differentially expressed genes (DEGs) by intersecting three datasets, GSE41328, GSE37364, and GSE15960 from Gene Expression Omnibus database, to maximize the accuracy of the results. Preliminary analysis of the DEGs was then performed using online gene analysis datasets, such as DAVID, UCSC Cancer Genome Browser, CBioPortal, STRING, and UCSC Cancer Genome Browser. Cytoscape was utilized to visualize the protein perception interaction network of DEGs, and the bubble map of GO and KEGG enrichment function was demonstrated using the R package. The Molecular Complex Detection (MCODE), Biological Network Gene Oncology (BiNGO) plug-in in Cytoscape, was applied to further screen the DEGs to obtain 15 seed genes, which were IL1RN, GALNT12, ADH6, SCN7A, CXCL1, FGF18, SOX9, ACACB, PRRX1, MZB1, SLC22A3, CNNM4, LY6E, IFITM2, and GDPD3. Among them, IL1RN, ADH6, SCN7A, ACACB, MZB1, and GDPD3 exhibited statistically significant survival differences, whereas limited studies were conducted in CRC. Based on the enrichment results of the "Gene Ontology"(GO) and "Kyoto Encyclopedia of Genes and genomes "(KEGG) as well as documented findings of key genes, we further emphasized the potential of IL1RN and PRRX1 as markers of immune infiltrates in CRC and confirmed our hypothesis by compiling data from the UALCAN, Tumor Immune Estimation Resource, and TISIDB databases for these two genes. The above-mentioned genes might offer a valuable insight into the diagnosis, immunotherapeutic targets, and prognosis of CRC.

Integrative Analysis Revealed Stemness Features and a Novel Stemness-Related Classification in Colorectal Cancer Patients

Cancer stem cells play crucial roles in colorectal cancer (CRC) tumorigenesis and treatment response. This study aimed to determine the value of the mRNA stemness index (mRNAsi) in CRC and introduce a stemness-related classification to predict the outcome of patients. mRNAsi scores and RNA sequence data of CRC patients were analyzed. We found that high mRNAsi scores were related to early-stage CRC and a better patient prognosis. Two stemness-based subtypes (subtype I and II) were identified. Patients in subtype I presented a significantly better prognosis than those in subtype II. Patients in these two subtype groups presented significantly different tumor immunity scores and immune cell infiltration patterns. Genomic variations revealed that patients in subtype I had a lower tumor mutation burden than those in subtype II. A three-gene stemness subtype predictor was established, showing good diagnostic value in discriminating patients in different subtypes. A prognostic signature based on five stemness-related genes was established and validated in two independent cohorts and clinical samples, showing a better predictive performance than other clinical parameters. We concluded that mRNAsi scores were associated with the clinical outcome in CRC patients. The stemness-related classification was a promising prognostic predictor for CRC patients.

An integrative in-silico analysis discloses a novel molecular subset of colorectal cancer possibly eligible for immune checkpoint immunotherapy

BACKGROUND

Historically, the molecular classification of colorectal cancer (CRC) was based on the global genomic status, which identified microsatellite instability in mismatch repair (MMR) deficient CRC, and chromosomal instability in MMR proficient CRC. With the introduction of immune checkpoint inhibitors, the microsatellite and chromosomal instability classification regained momentum as the microsatellite instability condition predicted sensitivity to immune checkpoint inhibitors, possibly due to both high tumor mutation burden (TMB) and high levels of infiltrating lymphocytes. Conversely, proficient MMR CRC are mostly resistant to immunotherapy. To better understand the relationship between the microsatellite and chromosomal instability classification, and eventually discover additional CRC subgroups relevant for therapeutic decisions, we developed a computational pipeline that include molecular integrative analysis of genomic, epigenomic and transcriptomic data.

RESULTS

The first step of the pipeline was based on unsupervised hierarchical clustering analysis of copy number variations (CNVs) versus hypermutation status that identified a first CRC cluster with few CNVs enriched in Hypermutated and microsatellite instability samples, a second CRC cluster with a high number of CNVs mostly including non-HM and microsatellite stable samples, and a third cluster (7.8% of the entire dataset) with low CNVs and low TMB, which shared clinical-pathological features with Hypermutated CRCs and thus defined Hypermutated-like CRCs. The mutational features, DNA methylation profile and base substitution fingerprints of these tumors revealed that Hypermutated-like patients are molecularly distinct from Hypermutated and non-Hypermutated tumors and are likely to develop and progress through different genetic events. Transcriptomic analysis highlighted further differences amongst the three groups and revealed an inflamed tumor microenvironment and modulation Immune Checkpoint Genes in Hypermutated-like CRCs.

CONCLUSION

Therefore, our work highlights Hypermutated-like tumors as a distinct and previously unidentified CRC subgroup possibly responsive to immune checkpoint inhibitors. If further validated, these findings can lead to expanding the fraction of patients eligible to immunotherapy.

Lipid-Based Nanoparticle Formulation of Diallyl Trisulfide Chemosensitizes the Growth Inhibitory Activity of Doxorubicin in Colorectal Cancer Model: A Novel In Vitro, In Vivo and In Silico Analysis

Garlic’s main bioactive organosulfur component, diallyl trisulfide (DATS), has been widely investigated in cancer models. However, DATS is not suitable for clinical use due to its low solubility. The current study seeks to improve DATS bioavailability and assess its chemopreventive and chemosensitizing properties in an AOM-induced colorectal cancer model. The polyethylene glycol coated Distearoylphosphatidylcholine/Cholesterol (DSPC/Chol) comprising DATS-loaded DATSL and doxorubicin (DOXO)-encapsulated DOXL liposomes was prepared and characterized. The changes in the sensitivity of DATS and DOXO by DATSL and DOXL were evaluated in RKO and HT-29 colon cancer cells. The synergistic effect of DATSL and DOXL was studied by cell proliferation assay in the combinations of IC₁₀, IC₂₅, and IC₃₅ of DATSL with the IC₁₀ of DOXL. AOM, DATSL, and DOXL were administered to different groups of mice for a period of 21 weeks. The data exhibited ~93% and ~46% entrapment efficiency of DATSL and DOXL, respectively. The size of sham liposomes was 110.5 nm, whereas DATSL and DOXL were 135.5 nm and 169 nm, respectively. DATSL and DOXL exhibited significant sensitivity in the cell proliferation experiment, lowering their IC₅₀ doses by more than 8- and 14-fold, respectively. However, the DATSL IC₁₀, IC₂₅, and IC₃₅ showed escalating chemosensitivity, and treated the cells in combination with DOXL IC₁₀. Analysis of histopathological, cancer marker enzymes, and antioxidant enzymes revealed that the high dose of DATSL pretreatment and DOXL chemotherapy is highly effective in inhibiting AOM-induced colon cancer promotion. The combination of DATSL and DOXL indicated promise as a colorectal cancer treatment in this study. Intermolecular interactions of DATS and DOXO against numerous cancer targets by molecular docking indicated MMP-9 as the most favourable target for DATS exhibiting binding energy of −4.6 kcal/mol. So far, this is the first research to demonstrate the chemopreventive as well as chemosensitizing potential of DATSL in an animal model of colorectal cancer.

The Effect of Liposomal Diallyl Disulfide and Oxaliplatin on Proliferation of Colorectal Cancer Cells: In Vitro and In Silico Analysis

Diallyl disulfide (DADS) is one of the main bioactive organosulfur compounds of garlic, and its potential against various cancer models has been demonstrated. The poor solubility of DADS in aqueous solutions limits its uses in clinical application. The present study aimed to develop a novel formulation of DADS to increase its bioavailability and therapeutic potential and evaluate its role in combination with oxaliplatin (OXA) in the colorectal cancer system. We prepared and characterized PEGylated, DADS (DCPDD), and OXA (DCPDO) liposomes. The anticancer potential of these formulations was then evaluated in HCT116 and RKO colon cancer cells by different cellular assays. Further, a molecular docking-based computational analysis was conducted to determine the probable binding interactions of DADS and OXA. The results revealed the size of the DCPDD and DCPDO to be 114.46 nm (95% EE) and 149.45 nm (54% EE), respectively. They increased the sensitivity of the cells and reduced the IC₅₀ several folds, while the combinations of them showed a synergistic effect and induced apoptosis by 55% in the cells. The molecular docking data projected several possible targets of DADS and OXA that could be evaluated more precisely by these novel formulations in detail. This study will direct the usage of DCPDD to augment the therapeutic potential of DCPDO against colon cancer in clinical settings.

Activating transcription factor 3-activated long noncoding RNA forkhead box P4-antisense RNA 1 aggravates colorectal cancer progression by regulating microRNA-423-5p/nucleus accumbens associated 1 axis

Long noncoding RNAs (lncRNAs) have vital roles in the progression of colorectal cancer (CRC). Forkhead box P4-antisense RNA 1 (FOXP4-AS1) showed a potential unfavorable prognostic factor for CRC, while its underlying mechanism remains elusive. Thus, the goal of this research is to determine mechanism of FOXP4-AS1 in CRC occurrence and development. Herein, a Dual-luciferase reporter assay was performed to assess the regulation of miR-423-5p to nucleus accumbens-associated protein 1 (NACC1) and activating transcription factor 3 (ATF3) to FOXP4-AS1 promoter. Hematoxylin-eosin (H&E) staining was performed to detect the pathological changes of tumor tissues. Flow cytometry, cell counting kit 8, Transwell, and wound healing assays were conducted to assess apoptosis, proliferation, migration, and invasion of CRC cells, respectively. The results showed that FOXP4-AS1 was highly expressed in CRC cell lines and tissues. CRC progression was promoted by the overexpression of FOXP4-AS1 in HTC116 cells and animal models. Furthermore, FOXP4-AS1 served as a molecular sponge for miR-423-5p, and NACC1 is a direct target of miR-423-5p. MiR-423-5p silencing or overexpression of NACC1 increased proliferation, migration, and invasion of HCT116 cells while suppressing apoptosis. We also found that the upregulation of FOXP4-AS1 was activated by ATF3 in CRC cells. Collectively, our results demonstrated that ATF3-activated FOXP4-AS1 aggravates CRC progression by regulating miR-423-5p/NACC1 axis, indicating a new target for CRC treatment.