Colorectal Cancer Biomarkers: Where Are We Now?

The histological and molecular characteristics of early-onset colorectal cancer: a systematic review and meta-analysis

Background

Early-onset colorectal cancer (CRC), defined as diagnosis before age 50, has increased in recent decades. Although more often diagnosed at advanced stage, associations with other histological and molecular markers that impact prognosis and treatment remain to be clarified. We conducted a systematic review and meta-analysis concerning the prevalence of prognostic and predictive tumor markers for early- vs. late-onset CRC, including oncogene mutations, microsatellite instability (MSI), and emerging markers including immune cells and the consensus molecular subtypes.

Methods

We systematically searched PubMed for original research articles published between April 2013-January 2024. Included studies compared the prevalence of tumor markers in early- vs. late-onset CRC. A meta-analysis was completed and summary odds ratios (ORs) with 95% confidence intervals (CIs) were obtained from a random effects model via inverse variance weighting. A sensitivity analysis was completed to restrict the meta-analysis to studies that excluded individuals with Lynch syndrome, a hereditary condition that influences the distribution of tumor markers for early-onset CRC.

Results

In total, 149 articles were identified. Tumors from early-onset CRC are less likely to include mutations in KRAS (OR, 95% CI: 0.91, 0.85-0.98), BRAF (0.63, 0.51-0.78), APC (0.70, 0.58-0.84), and NRAS (0.88, 0.78-1.00) but more likely to include mutations in PTEN (1.68, 1.04-2.73) and TP53 (1.34, 1.24-1.45). After limiting to studies that excluded Lynch syndrome, the associations between early-onset CRC and BRAF (0.77, 0.64-0.92) and APC mutation (0.81, 0.67-0.97) were attenuated, while an inverse association with PIK3CA mutation was also observed (0.88, 0.78-0.99). Early-onset tumors are less likely to develop along the CpG Island Methylator Phenotype pathway (0.24, 0.10-0.57), but more likely to possess adverse histological features including high tumor grade (1.20, 1.15-1.25), and mucinous (1.22, 1.16-1.27) or signet ring histology (2.32, 2.08-2.57). A positive association with MSI status (1.31, 1.11-1.56) was also identified. Associations with immune markers and the consensus molecular subtypes are inconsistent.

Discussion

A lower prevalence of mutations in KRAS and BRAF is consistent with extended survival and superior response to targeted therapies for metastatic disease. Conversely, early-onset CRC is associated with aggressive histological subtypes and TP53 and PTEN mutations, which may serve as therapeutic targets.

Plasma Circulating mRNA Profile for the Non-Invasive Diagnosis of Colorectal Cancer Using NanoString Technologies

Colorectal cancer (CRC) is one of the most prevalent cancers and the second leading cause of cancer deaths in developed countries. Early CRC may have no symptoms and symptoms usually appear with more advanced diseases. Regular screening can identify people who are at increased risk of CRC in order to offer earlier treatment. A cost-effective non-invasive platform for the screening and monitoring of CRC patients allows early detection and appropriate treatment of the disease, and the timely application of adjuvant therapy after surgical operation is needed. In this study, a cohort of 71 plasma samples that include 48 colonoscopy- and histopathology-confirmed CRC patients with TNM stages I to IV were recruited between 2017 and 2019. Plasma mRNA profiling was performed in CRC patients using NanoString nCounter. Normalized data were analyzed using a Mann-Whitney U test to determine statistically significant differences between samples from CRC patients and healthy subjects. A multiple-group comparison of clinical phenotypes was performed using the Kruskal-Wallis H test for statistically significant differences between multiple groups. Among the 27 selected circulating mRNA markers, all of them were found to be overexpressed (gene expression fold change > 2) in the plasma of patients from two or more CRC stages. In conclusion, NanoString-based targeted plasma CRC-associated mRNAs circulating the marker panel that can significantly distinguish CRC patients from a healthy population were developed for the non-invasive diagnosis of CRC using peripheral blood samples.

Racial disparities in colorectal cancer clinicopathological and molecular tumor characteristics: a systematic review

PURPOSE

African Americans have the highest colorectal cancer (CRC) mortality of all racial groups in the USA, which may relate to differences in healthcare access or advanced stage at diagnosis. Recent evidence indicates that differences in tumor characteristics may also underlie disparities in mortality. To highlight recent findings and areas for investigation, we completed the first systematic review of racial disparities in CRC tumor prognostic markers, including clinicopathological markers, microsatellite instability (MSI), oncogene mutations, and novel markers, including cancer stem cells and immune markers.

METHODS

Relevant studies were identified via PubMed, limited to original research published within the last 10 years. Ninety-six articles were identified that compared the prevalence of mortality-related CRC tumor characteristics in African Americans (or other African ancestry populations) to White cases.

RESULTS

Tumors from African ancestry cases are approximately 10% more likely to contain mutations in KRAS, which confer elevated mortality and resistance to epidermal growth factor receptor inhibition. Conversely, African Americans have approximately 50% lower odds for BRAF-mutant tumors, which occur less frequently but have similar effects on mortality and therapeutic resistance. There is less consistent evidence supporting disparities in mutations for other oncogenes, including PIK3CA, TP53, APC, NRAS, HER2, and PTEN, although higher rates of PIK3CA mutations and lower prevalence of MSI status for African ancestry cases are supported by recent evidence. Although emerging evidence suggests that immune markers reflecting anti-tumor immunity in the tumor microenvironment may be lower for African American cases, there is insufficient evidence to evaluate disparities in other novel markers, cancer stem cells, microRNAs, and the consensus molecular subtypes.

CONCLUSION

Higher rates of KRAS-mutant tumors in in African Americans may contribute to disparities in CRC mortality. Additional work is required to understand whether emerging markers, including immune cells, underlie the elevated CRC mortality observed for African Americans.

A Systems Biology Approach Unveils a Critical Role of DPP4 in Upper Gastrointestinal Cancer Patient Outcomes

Gastrointestinal (GI) cancers comprise of cancers that affect the digestive system and its accessory organs. The late detection and poor prognosis of GI cancer emphasizes the importance of identifying reliable and precise biomarkers for early diagnosis and prediction of prognosis. The membrane-bound glycoprotein dipeptidyl-peptidase 4 (DPP4), also known as CD26, is ubiquitously expressed and has a wide spectrum of biological roles. The role of DPP4/CD26 in tumor progression in different types of cancers remains elusive. However, the link between DPP4 and tumor-infiltrating cells, as well as its prognostic significance in malignancies, still require further investigation. This study was intended to elucidate the correlation of DPP4 expression and survival along with prognosis, followed by its associated enriched molecular pathways and immune cell marker levels in upper GI cancers. Results demonstrated a strong correlation between increased DPP4 expression and a worse prognosis in esophageal and gastric cancer and the co-expressed common genes with DPP4 were associated with crucial molecular pathways involved in tumorigenesis. Additionally, DPP4 was shown to be significantly linked to several immune infiltrating cell marker genes, including Macrophages (M1, M2 and Tumor Associated Macrophages), neutrophils, Treg, T-cell exhaustion, Th1 and Th2. Overall, our findings suggest that DPP4 may serve as a substantial prognostic biomarker, a possible therapeutic target, as well as it can play a critical role in the regulation of immune cell invasion in patients with gastroesophageal (esophageal, gastroesophageal junction and gastric) cancer. KEY WORDS: DPP4, integrated analysis, GI cancer, gastroesophageal cancer, gastroesophageal junction, prognosis.

A detailed multi-omics analysis of GNB2 gene in human cancers

Abstract The Guanine-nucleotide binding protein 2 (GNB2) encodes for β2 subunit (Gβ2) of the G-protein complex. Keeping in view the increased demand of reliable biomarkers in cancer, the current study was planned to extensively explored GNB2 expression variation and its roles in different cancers using online available databases and diverse methodology. In view of our results, the GNB2 was notably up-regulated relative to corresponding controls in twenty three cancer types. As well, the elevated expression of GNB2 was found to be associated with the reduced overall survival (OS) of the Liver Hepatocellular Carcinoma (LIHC) and Rectum Adenocarcinoma (READ) only out of all analyzed cancer types. This implies GNB2 plays vital role in the tumorigenesis of LIHC and READ. Several additional analysis also explored six critical pathways and few important correlations related to GNB2 expression and different other parameters such as promoter methylation, tumor purity, CD8+ T immune cells infiltration, and genetic alteration, and chemotherapeutic drugs. In conclusion, GNB2 gene has been identified in this study as a shared potential biomarker (diagnostic and prognostic) of LIHC and READ.

Tumor circulating biomarkers in colorectal cancer

CRC is a major global health concern and is responsible for a significant number of cancer-related deaths each year. The successful treatment of CRC becomes more difficult when it goes undetected until it has advanced to a later stage. Diagnostic biomarkers can play a critical role in the early detection of CRC, which leads to improved patient outcomes and increased survival rates. It is important to develop reliable biomarkers for the early detection of CRC to enable timely diagnosis and treatment. To date, CRC detection methods such as endoscopy, blood, and stool tests are imperfect and often only identify cases in the later stages of the disease. To overcome these limitations, researchers are turning to molecular biomarkers as a promising avenue for improving CRC detection. Diagnostic information can be provided more reliably through a noninvasive approach using biomarkers such as mRNA, circulating cell-free DNA, micro-RNA, long non-coding RNA, and proteins. These biomarkers can be found in blood, tissue, feces, and volatile organic compounds. The identification of molecular biomarkers with high sensitivity and specificity for early detection of CRC that are safe, cost-effective, and easily measurable remains a significant challenge for researchers. In this article, we will explore the latest advancements in blood-based diagnostic biomarkers for CRC and their potential impact on improving patient survival rates.

Amino Acid Profiles in the Biological Fluids and Tumor Tissue of CRC Patients

Amino acids are the building blocks of proteins and essential players in pathways such as the citric acid and urea cycle, purine and pyrimidine biosynthesis, and redox cell signaling. Therefore, it is unsurprising that these molecules have a significant role in cancer metabolism and its metabolic plasticity. As one of the most prevalent malign diseases, colorectal cancer needs biomarkers for its early detection, prognostic, and prediction of response to therapy. However, the available biomarkers for this disease must be more powerful and present several drawbacks, such as high costs and complex laboratory procedures. Metabolomics has gathered substantial attention in the past two decades as a screening platform to study new metabolites, partly due to the development of techniques, such as mass spectrometry or liquid chromatography, which have become standard practice in diagnostic procedures for other diseases. Extensive metabolomic studies have been performed in colorectal cancer (CRC) patients in the past years, and several exciting results concerning amino acid metabolism have been found. This review aims to gather and present findings concerning alterations in the amino acid plasma pool of colorectal cancer patients.

Therapeutic efficacy of α-lactalbumin coated oleic acid based liposomes against colorectal carcinoma in Caco-2 cells and DMH-treated albino rats

Colorectal cancer (CRC) is a malignant tumor recognized as a major cause of morbidity and mortality throughout the world. Therefore, novel liposomes of oleic acid coated with camel α-lactalbumin (α-LA coated liposomes) were developed for their potential antitumor activity against CRC, both in vitro and in DMH-induced CRC-modeled animal. In vitro results indicated the high safety of α-LA coated liposomes towards normal human cells with potent antitumor activity against Caco-2 cells at an IC50 value of 57.01 ± 3.55 µM with selectivity index of 6.92 ± 0.48. This antitumor activity has been attributed to induction of the apoptotic mechanism, as demonstrated by nuclear condensation and arrest of Caco-2 cells in sub-G1 populations. α-LA coated liposomes also revealed a significant up-regulation of the p53 gene combined with a down-regulation of the Bcl2 gene. Moreover, in vivo results revealed that treatment of induced-CRC modeled animals with α-LA coated liposomes for six weeks markedly improved the CRC-disorders; this was achieved from the significant reduction in the values of AFP, CEA, CA19.9, TNF-α, IL-1β, MDA, and NO coupled with remarkable rise in SOD, GPx, GSH, CAT, and CD4+ levels. The histopathological findings asserted the therapeutic potential of α-LA coated liposomes in the treatment of CRC. Therefore, the present results proved the antitumor activity of α-LA coated liposomes against CRC through the restoration of impaired oxidative stress, improved immune response, and reduced inflammation.Communicated by Ramaswamy H. Sarma.

Label-free quantitative proteomics reveals aberrant expression levels of LRG, C9, FN, A1AT and AGP1 in the plasma of patients with colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is one of the major causes of cancer-related death worldwide. Although commercial biomarkers of CRC are currently available, they are still lacking in terms of sensitivity and specificity; thus, searching for reliable blood-based biomarkers are important for the primary screening of CRC.

METHODS

Plasma samples of patients with non-metastatic (NM) and metastatic (M) CRC and healthy controls were fractionated using MARS-14 immunoaffinity chromatography. The flow-through and elute fractions representing low- and high-abundant proteins, respectively, were analyzed by label-free quantitative proteomics mass spectrometry. The functional analysis of the proteins with greater than 1.5-fold differential expression level between the CRC and the healthy control groups were analyzed for their biological processes and molecular functions. In addition, the levels of plasma proteins showing large alterations in CRC patients were confirmed by immunoblotting using two independent cohorts. Moreover, receiver operating characteristic (ROC) curve analysis was performed for individual and combinations of biomarker candidates so as to evaluate the diagnostic performance of biomarker candidates.

RESULTS

From 163 refined identifications, five proteins were up-regulated and two proteins were down-regulated in NM-CRC while eight proteins were up-regulated and three proteins were down-regulated in M-CRC, respectively. Altered plasma proteins in NM-CRC were mainly involved in complement activation, while those in M-CRC were clustered in acute-phase response, complement activation, and inflammatory response. Results from the study- and validation-cohorts indicate that the levels of leucine-rich alpha-2-glycoprotein-1(LRG), complement component C9 (C9), alpha-1-acid glycoprotein 1 (AGP1), and alpha-1-antitrypsin (A1AT) were statistically increased, while fibronectin (FN) level was statistically decreased in CRC patients compared to healthy controls, with most alterations found in a metastatic stage-dependent manner. ROC analysis revealed that FN exhibited the best diagnostic performance to discriminate CRC patients and healthy controls while AGP1 showed the best discrimination between the disease stages in both cohorts. The combined biomarker candidates, FN + A1AT + AGP1, exhibited perfect discriminatory power to discriminate between the CRC population and healthy controls whereas LRG + A1AT + AGP1 was likely to be the best panel to discriminate the metastatic stages in both cohorts.

CONCLUSIONS

This study identified and quantified distinct plasma proteome profiles of CRC patients. Selected CRC biomarker candidates including FN, LRG, C9, A1AT, and AGP1 may be further applied for screening larger cohorts including disease groups from other types of cancer or other diseases.

Targeted EpCAM-binding for the development of potent and effective anticancer proteins

Protein-based cancer therapies are considered an alternative to conventional anticancer regimens, providing multifunctional properties while showing low toxicity. However, its widespread use is limited by absorption and instability issues, resulting in higher dosage requirements and a prolonged onset of bioactivity to elicit the desired response. Here, we developed a non-invasive antitumor treatment using designed ankyrin repeat protein (DARPin)-anticancer protein-conjugate that specifically targets the cancer biomarker, epithelial cell adhesion molecule (EpCAM). The DARPin-anticancer proteins bind to EpCAM-positive cancer cells and improve the in vitro anticancer efficacy by over 100-folds within 24 h, where the DARPin-tagged human lactoferrin fragment (drtHLF4) IC50 value is within the nanomolar range. Orally administered drtHLF4 was readily absorbed into the systemic flow of the HT-29 cancer murine model, exerting its anticancer effect on other tumors in the host body. Orally administered drtHFL4 cleared HT29-colorectal tumors using a single dose, whereas intratumoral injection cleared HT29-subcutaneous tumors within three doses. This approach addresses the limitations of other protein-based anticancer treatments by providing a non-invasive anticancer therapy with improved potency and tumor-specificity.

Establishment and validation of reference intervals for tumor markers (AFP, CEA, CA19-9, CA15-3, CA125, PSA, HE4, Cyfra 21-1, and ProGRP) in primary care centers in Korea: A cross-sectional retrospective study

Background and Aims

The reference interval (RI) for a tumor marker may vary between populations, detection systems, and the methods used to obtain their values. The aims of this study were to establish age- and sex-specific RIs for the following nine common tumor markers and to validate the established RIs in Korean adults: alpha fetoprotein (AFP), carcinoembryonic antigen (CEA), cancer antigen (CA) 19-9, CA15-3, CA125, Human epididymis protein 4 (HE4), total prostate specific antigen, cytokeratin fragment (Cyfra) 21-1, and progastrin-releasing peptide (ProGRP).

Methods

This cross-sectional study consecutively selected 214,159 individuals (aged 18-98 years) who underwent health checkups at 16 health-promotion centers in 13 Korean cities. Finally, 62,752 examinees were used to establish the RIs after removing outliers. RIs were established using an indirect method according to the CLSI EP28-A3C guideline. The established RIs were validated by calculating the proportion of individuals outside each RI.

Results

Sex-related differences were observed for AFP, CEA, CA19-9, Cyfra 21-1, and ProGRP (p < 0.05): AFP, CEA and Cyfra 21-1 were higher in males, and CA19-9 and proGRP were higher in females. Most of the tumor markers except CA15-3 and CA125 increased with age: CA125 decreased at ≥50 years of age (p < 0.05), while CA15-3 did not vary with age. Less than 5% of subjects were outside all RIs (the 2.5th and 97.5th percentiles) established in the present study. Meanwhile, less than 3% of the healthy reference subjects fell outside the current and manufacturers' RIs of all tumor markers except Cyfra 21-1.

Conclusion

This study has determined age- and sex-specific RIs for nine common tumor markers in the healthy Korean population, which could be useful for clinicians making clinical decisions and assessments.

Roles of anoikis in colorectal cancer therapy and the assessment of anoikis-regulatory molecules as therapeutic targets

Colorectal cancer (CRC) is a deadly malignancy and therapeutic approaches for CRC are evolving every day. Anoikis is a key mechanism for programmed cell death of cancer cells that undergo anchorage-independent growth at a different matrix than the one which is expected. Yet, anoikis is a less studied mechanism of cell death in comparison to other mechanisms such as apoptosis. Relating to this, resistance to anoikis among cancer cells remains critical for improved metastasis and survival in a new environment evading anoikis. Since CRC cells have the ability to metastasize from proximal sites to secondary organs such as liver and promote cancer in those distant sites, a clear knowledge of the mechanisms essential for anchorage-independent growth and subsequent metastasis is necessary to counteract CRC progression and spread. Therefore, the identification of novel drug candidates and studying the roles of anoikis in assisting CRC therapy using such drugs can prevent anchorage-independent cancer cell growth. Additionally, the identification of novel biomarkers or therapeutic targets seems essential for implementing superior therapy, impeding relapse among malignant cells and improving the survival rate of clinical patients. As there are no reviews published on this topic till date, anoikis as a mechanism of cell death and its therapeutic roles in CRC are discussed in this review. In addition, several molecules were identified as therapeutic targets for CRC.

Enterotypical Prevotella and three novel bacterial biomarkers in preoperative stool predict the clinical outcome of colorectal cancer

BACKGROUND

A significant proportion of colorectal cancer (CRC) patients suffer from early recurrence and progression after surgical treatment. Although the gut microbiota is considered as a key player in the initiation and progression of CRC, most prospective studies have been focused on a particular pathobionts such as Fusobacterium nucleatum. Here, we aimed to identify novel prognostic bacteria for CRC by examining the preoperative gut microbiota through 16S ribosomal RNA gene sequencing.

RESULTS

We collected stool samples from 333 patients with primary CRC within 2 weeks before surgery and followed up the patients for a median of 27.6 months for progression and 43.6 months for survival. The sequence and prognosis data were assessed using the log-rank test and multivariate Cox proportional hazard analysis. The gut microbiota was associated with the clinical outcomes of CRC patients (P_progress = 0.011, P_decease = 0.007). In particular, the high abundance of Prevotella, a representative genus of human enterotypes, indicated lower risks of CRC progression (P = 0.026) and decease (P = 0.0056), while the occurrence of Alistipes assigned to Bacteroides sp., Pyramidobacter piscolens, Dialister invisus, and Fusobacterium nucleatum indicated a high risk of progression. A microbiota-derived hazard score considering the five prognostic bacteria accurately predicted CRC progression in 1000 random subsamples; it outperformed widely accepted clinical biomarkers such as carcinoembryonic antigen and lymphatic invasion, after adjustment for the clinicopathological stage (adjusted HR 2.07 [95% CI, 1.61-2.64], P = 7.8e-9, C-index = 0.78). PICRUSt2 suggested that microbial pathways pertaining to thiamine salvage and L-histidine degradation underlie the different prognoses.

CONCLUSIONS

The enterotypical genus Prevotella was demonstrated to be useful in improving CRC prognosis, and combined with the four pathobionts, our hazard score based on the gut microbiota should provide an important asset in predicting medical outcomes for CRC patients. Video Abstract.

The Antioxidant and Antitumor Efficiency of Litophyton sp. Extract in DMH-Induced Colon Cancer in Male Rats

One of the most common tumors to cause death worldwide is colon cancer. This study aims to investigate the antitumor potency of Litophyton sp. methanolic extract (LME) against DMH-induced colon cancer in adult male rats. Group (1) normal rats served as the control, group (2) normal rats were ip-injected with LME at a dose of 100 μg/kg/day, group (3) DMH-induced colon cancer animals, and group (4) colon cancer-modeled animals were treated with LME (100 μg/kg/day) for six weeks. The results revealed that injection of LME markedly regenerated the colon cancer pathophysiological disorders; this was monitored from the significant reduction in the values of serum biomarkers (CEA, CA19.9, AFP), cytokines (TNF-α and IL1β), and biochemical measurements (ALAT, ASAT, urea, creatinine, cholesterol, and triglycerides) matched significant increase of apoptotic biomarkers (CD4+); similarly, colon DNA fragmentation, MDA, and NO levels were down-regulated. In contrast, a remarkable upregulation in colon SOD, GPx, GSH, and CAT levels was noted. Moreover, the colon histopathological architecture showed obvious regenerations. Chromatography of LME resulted in the purification of two polyhydroxylated steroids (1 and 2) with potential cytotoxic activities. LME performed therapeutic potential colon tumorigenesis; therefore, LME may have a promising chemo-preventive feature against colon cancer, probably via enhancement of the apoptosis pathway, improvement of the immune response, reduction of inflammation, or/and restoration of the impaired oxidative stress.

Liquid chromatography coupled to high-resolution mass spectrometry metabolomics: A useful tool for investigating tumor secretome based on a three-dimensional co-culture model

Three-dimensional (3D) cell culture technologies, which more closely mimic the complex microenvironment of tissue, are being increasingly evaluated as a tool for the preclinical screening of clinically promising new molecules, and studying of tissue metabolism. Studies of metabolites released into the extracellular space (secretome) allow understanding the metabolic dynamics of tissues and changes caused by therapeutic interventions. Although quite advanced in the field of proteomics, studies on the secretome of low molecular weight metabolites (< 1500 Da) are still very scarce. We present an untargeted metabolomic protocol based on the hybrid technique of liquid chromatography coupled with high-resolution mass spectrometry for the analysis of low-molecular-weight metabolites released into the culture medium by 3D cultures and co-culture (secretome model). For that we analyzed HT-29 human colon carcinoma cells and 3T3-L1 preadipocytes in 3D-monoculture and 3D-co-culture. The putative identification of the metabolites indicated a sort of metabolites, among them arachidonic acid, glyceric acid, docosapentaenoic acid and beta-Alanine which are related to cancer and obesity. This protocol represents a possibility to list metabolites released in the extracellular environment in a comprehensive and untargeted manner, opening the way for the generation of metabolic hypotheses that will certainly contribute to the understanding of tissue metabolism, tissue-tissue interactions, and metabolic responses to the most varied interventions. Moreover, it brings the potential to determine novel pathways and accurately identify biomarkers in cancer and other diseases. The metabolites indicated in our study have a close relationship with the tumor microenvironment in accordance with the literature review.

Targeted Next-Generation Sequencing-Based Multiple Gene Mutation Profiling of Patients with Rectal Adenocarcinoma Receiving or Not Receiving Neoadjuvant Chemoradiotherapy

This study investigated whether oncogenic and tumor-suppressive gene mutations are involved in the differential outcomes of patients with rectal carcinoma receiving neoadjuvant chemoradiotherapy (nCRT). Genomic DNA was obtained from formalin-fixed paraffin-embedded (FFPE) specimens of patients with rectal carcinoma who received a complete nCRT course. Gene mutation status was examined in specimens from patients before and after nCRT by using the AmpliSeq platform. Our data revealed that the nonsynonymous p53, APC, KRAS, CDKN2A, and EGFR mutations were observed in 93.1%, 65.5%, 48.6%, and 31% of the patients with rectal adenocarcinoma, respectively. BRAF, FBXW7, PTEN, and SMAD4 mutations were observed in 20.7% of patients with rectal carcinoma. The following 12 gene mutations were observed more frequently in the patients exhibiting a complete response than in those demonstrating a poor response before nCRT: ATM, BRAF, CDKN2A, EGFR, FLT3, GNA11, KDR, KIT, PIK3CA, PTEN, PTPN11, SMAD4, and TP53. In addition, APC, BRAF, FBXW7, KRAS, SMAD4, and TP53 mutations were retained after nCRT. Our results indicate a complex mutational profile in rectal carcinoma, suggesting the involvement of BRAF, SMAD4, and TP53 genetic variants in the outcomes of patients with nCRT.

Diagnostic and prognostic biomarkers in colorectal cancer and the potential role of exosomes in drug delivery

Colorectal cancer (CRC) is third most common cancer with second most common cause of death worldwide. One fourth to one fifth of the CRC cases are detected at advance stage. Early detection of colorectal cancer might help in decreasing mortality and morbidity worldwide. CRC being a heterogeneous disease, new non-invasive approaches are needed to complement and improve the screening and management of CRC. Reliable and early detectable biomarkers would improve diagnosis, prognosis, therapeutic responses, and will enable the prediction of drug response and recurrence risk. Over the past decades molecular research has demonstrated the potentials of CTCs, ctDNAs, circulating mRNA, ncRNAs, and exosomes as tumor biomarkers. Non-invasive screening approaches using fecal samples for identification of altered gut microbes in CRC is also gaining attention. Exosomes can be potential candidates that can be employed in the drug delivery system. Further, the integration of in vitro, in vivo and in silico models that involve CRC biomarkers will help to understand the interactions occurring at the cellular level. This review summarizes recent update on CRC biomarkers and their application along with the nanoparticles followed by the application of organoid culture in CRC.

Machine Learning-Based Identification of Colon Cancer Candidate Diagnostics Genes

Simple Summary

We developed a predictive approach using different machine learning methods to identify a number of genes that can potentially serve as novel diagnostic colon cancer biomarkers.

Abstract

Background: Colorectal cancer (CRC) is the third leading cause of cancer-related death and the fourth most commonly diagnosed cancer worldwide. Due to a lack of diagnostic biomarkers and understanding of the underlying molecular mechanisms, CRC’s mortality rate continues to grow. CRC occurrence and progression are dynamic processes. The expression levels of specific molecules vary at various stages of CRC, rendering its early detection and diagnosis challenging and the need for identifying accurate and meaningful CRC biomarkers more pressing. The advances in high-throughput sequencing technologies have been used to explore novel gene expression, targeted treatments, and colon cancer pathogenesis. Such approaches are routinely being applied and result in large datasets whose analysis is increasingly becoming dependent on machine learning (ML) algorithms that have been demonstrated to be computationally efficient platforms for the identification of variables across such high-dimensional datasets. Methods: We developed a novel ML-based experimental design to study CRC gene associations. Six different machine learning methods were employed as classifiers to identify genes that can be used as diagnostics for CRC using gene expression and clinical datasets. The accuracy, sensitivity, specificity, F1 score, and area under receiver operating characteristic (AUROC) curve were derived to explore the differentially expressed genes (DEGs) for CRC diagnosis. Gene ontology enrichment analyses of these DEGs were performed and predicted gene signatures were linked with miRNAs. Results: We evaluated six machine learning classification methods (Adaboost, ExtraTrees, logistic regression, naïve Bayes classifier, random forest, and XGBoost) across different combinations of training and test datasets over GEO datasets. The accuracy and the AUROC of each combination of training and test data with different algorithms were used as comparison metrics. Random forest (RF) models consistently performed better than other models. In total, 34 genes were identified and used for pathway and gene set enrichment analysis. Further mapping of the 34 genes with miRNA identified interesting miRNA hubs genes. Conclusions: We identified 34 genes with high accuracy that can be used as a diagnostics panel for CRC.

Amelioration of DMH-induced colon cancer by eupafolin through the reprogramming of apoptosis-associated p53/Bcl2/Bax signaling in rats

Introduction: Colorectal cancer is the third most common malignancy and the second most deadly cancer worldwide. In this present study, the effects of eupafolin on DMH-induced colon cancer in rats were assessed.

Methods: The acute and sub-acute oral toxicity study in the balb/c mice was performed to evaluate the LD50 dose and the chemotherapeutic doses of eupafolin. The colon cancer was induced in the animals through a single intraperitoneal injection (i.p) of 30 mg/kg of dimethylhydrazine followed by 2% DSS for 7 days in the drinking water in male Wistar rats. The rats were treated with eupafolin (50, 100, and 200 mg/kg) through oral route for 18 weeks. The animals were sacrificed and colon tissues were subsequently investigated for aberrant crypt foci (ACF), in vivo antioxidant studies, histology and immunohistochemical analysis, and apoptosis by TUNNEL technique after 18 weeks of eupafolin therapy.

Results: The acute oral toxicity data represented the LD50 dose of eupafolin which was found to be 500 mg/kg body weight. Along with that, the sub-acute toxicity study suggested the chemotherapeutic doses of eupafolin, that is, 50, 100, and 200 mg/kg body weight. Eupafolin therapy inhibits ACF development in rat colon mucosa efficiently. Additionally, eupafolin has improved the colonic lesions and the structural integrity of the colonic mucosa. Eupafolin therapy causes anti-oxidant enzymes such as superoxide dismutase, catalase, and glutathione to increase as well. Increased levels of P53, BAX, and PCNA and a simultaneous decrease in Bcl2 and IL-6 expressions show eupafolin therapy successfully regulated these biological markers in colorectal cancer. Eupafolin also induced apoptosis efficiently in the rat colon mucous membrane.

Conclusion: These results show that eupafolin can improve colon cancer by modulating the p53, Bcl2, BAX, and IL-6 pathways in rats.

Dysregulated Expression of Long Non-Coding RNA MINCR and EZH2 in Colorectal Cancer

BACKGROUND

As critical regulators, lncRNAs have attracted attention from researchers for diagnostic, prognostic, and therapeutic purposes in human carcinogenesis via interfering with mRNAs such as EZH2. Nevertheless, the potent roles and molecular mechanisms of these RNAs in CRC are not clearly known.

METHODS

In this study, the tissue expressions of lncRNA MINCR and EZH2 mRNA between colorectal tumors and polyps were compared with the adjacent normal tissues collected from 114 Iranian patients, using real-time PCR method. Furthermore, the correlation of the expression levels of MINCR and EZH2 with other clinical parameters was evaluated.

RESULTS

The significant overexpression of MINCR and EZH2 were observed in the CRC tissues compared to control tissues (p < 0.0001). This observation confirmed the association of these expression enhancements with the pathological stage of CRC patients.

CONCLUSION

Our findings revealed that the expression of MINCR significantly alters during CRC development, and it can be identified as a potential biomarker for the detection of CRC.

Harmol alleviates dimethylhydrazine induced colon cancer by downregulating Bcl2/IL-6/TNF-α expression in association with p53 mediated apoptosis

Objectives: Colorectal cancer is the world’s third most prevalent cancer. Herbal drugs are increasingly being used to treat a variety of disorders, including cancer, due to the severe adverse effects. Harmol, natural molecule containing β-carboline alkaloids, has aroused the interest of researchers due to its diverse biological functions, including anticancer properties. Methods: In this study, the chemotherapeutic effects of harmol have been investigated on HT-29 colon cancer cell line and a rat model of colon cancer. In the in vitro study the cytotoxicity assay, DAPI analysis and the flow cytometric analysis was performed to assess the anticancer efficacy of harmol in HT-29 cell. The colorectal cancer was developed in male Wistar rats through the administration of DMH followed by treatment with DSS. The rats were treated with harmol (100, 200 and 400 mg/kg) for 18 weeks. At the end of therapy, the colon tissues were assessed for ACF, in vivo antioxidant activity, histopathology, immunohistochemistry, immunofluorescence analysis and apoptosis assay. Results: The in vitro data suggested that the harmol therapy would significantly increase the percentage of early apoptosis in HT-29 cells through halting of G0/G1 phase. Furthermore, inhibition of ACF development with improved colonic abrasion and morphological features in colonic mucosal region were noted. Harmol treatment also increased the levels of antioxidants and p53 and downregulated Bcl2, IL-6 and TNF-α expression. Conclusion: These outcomes signify that harmol successfully recover colorectal carcinoma by reprogramming the p53, Bcl2, IL-6 and TNF-α pathway in rats.

Exploiting the efficacy of Tyro3 and folate receptors to enhance the delivery of gold nanoparticles into colorectal cancer cells in vitro

Colorectal cancer (CRC) is the fourth most common cancer in the world. Due to its asymptomatic nature, CRC is diagnosed at an advanced stage where the survival rate is <5%. Besides, CRC treatment using chemotherapy, radiotherapy and surgery often causes undesirable side-effects. As such, gold nanoparticles (GNPs) are envisaged in the field for the diagnosis and treatment of CRC. GNPs have unique physical, chemical and electrical properties at the nanoscale which make them suitable for application in biomedicine. However, for GNPs to become clinically effective, their internalisation efficiency in cancer cells must be enhanced. Folate receptor-α (FR) is overexpressed in CRC cells wherein FR helps in the uptake of folic acid within the cells. Tyro3, a novel tyrosine kinase receptor, drives cell proliferation and its overexpression is correlated with poor prognosis in CRC. Their upregulated expression in CRC cells relative to normal cells makes them an ideal target for GNPs using active targeting. Therefore, in this study receptors FR and Tyro3 were simultaneously targeted using specific antibody-coated GNPs in order to enhance the uptake and internalisation of GNPs in CRC cells in vitro. Four different types of coated-GNPs were synthesised GNPs-PEG, GNPs-anti-FR, GNPs-anti-Tyro3 and GNPs-anti-(FR + Tyro3) and incubated (0-50 ng) with three CRC cell lines namely CRL1790, CRL2159 and HCT116. Simultaneous targeting of these receptors by GNPs-anti-(FR + Tyro3) was found to be the most effective in internalisation in CRC cells compared with GNPs targeted singly to FR or Tyro3 (p <0.05). Besides this, results show that Tyro3 mediated similar internalisation efficacy to FR (p <0.05) in CRC cells using ICP-OES.

Suppressive effects of dental pulp stem cells and its conditioned medium on development and migration of colorectal cancer cells through MAPKinase pathways

OBJECTIVES

Mesenchymal stem cells (MSCs) extensively interact with cancer cells and other stromal cells in the tumor microenvironment. However, the role of MSCs in colorectal cancer (CRC) development and metastasis is controversial. Strong evidence demonstrated that conditioned medium (CM) obtained from MSCs regulates main cellular functions such as proliferation, differentiation, migration, and communication due to its cell secretomes. This study was designed to determine the inhibitory effect of dental pulp stem cells (DPSC) and its extracted conditioned medium (DPSC-CM) in CRC progression.

MATERIALS AND METHODS

The inhibitory effects of DPSC-CM on growth, apoptosis, and migration of CRC cells were evaluated by resazurin, flow cytometry of propidium iodide (PI) stained cells, and wound closure assay, respectively. Western blotting detected the expression of MAPKinase and apoptotic proteins. Also, the homing ability of DPSCs and the invasion ability of CRC cells under indirect co-culture were assayed by the Boyden chamber assay.

RESULTS

DPSC-CM reduced the viability and induced the apoptosis of CRC cells significantly. Western blot analysis confirmed the increase in cytochrome C, phospho-JNK/SAPK to JNK/SAPK ratio, cleaved-caspase 8 and 3 in treated CRC cells with DPSC-CM, and decrease in phospho-ERK (P44/42 MAPK) to ERK (P44/42 MAPK) ratio, which are involved in induction of apoptosis and growth inhibition of cancer cells with minimal change in normal cells. Also, DPSCs could migrate (homing ability) to Caco₂ and SW48 cells significantly.

CONCLUSION

To sum up, DPSC-CM had significant apoptotic and growth inhibitory effects on the CRC cells through the MAPKinase and apoptosis signaling pathways.

Aberrant Promoter Hypermethylation of p16 and RASSF1a Genes in Colorectal Cancer - Significance in Young Patients

OBJECTIVE

The clinical profile of colorectal cancers (CRC) in India is different from that described in western countries. Microsatellite instability and APC mutation explain the molecular biology of up to 50% of colorectal cancers. Global genome hypermethylation may be the cause in at least 20% of cases. Few studies from India have examined the epigenetic profile of colorectal cancers. This study was designed to study aberrant promoter hypermethylation of two select tumour suppressor genes (p16, RASSF1a) in patients with colorectal cancer and their association with clinicopathologic features.

METHODS

A total of 41 samples including controls were collected from colorectal cancer patients. DNA was isolated from tumour tissue, and methylation-specific PCR was performed for the 2 genes.

RESULTS

p16 and RASSF1a promoter hypermethylation was found in 26% and 48% of CRC cases, respectively. RASSF1a promoter hypermethylation was more often seen in young CRC patients aged 40 years or less, and this was found to be statistically significant (p value = 0.037).

CONCLUSION

RASSF1a hypermethylation is peculiar to rectal cancers and left-sided colonic tumours in young patients. Large-scale population-based studies with extensive genetic and epigenetic characterization are required for a better understanding and further validation of our findings. For individuals diagnosed with sporadic CRC, these studies on specimen might help predict prognosis and response to therapy.

Expression profiles of miR-196, miR-132, miR-146a, and miR-134 in human colorectal cancer tissues in accordance with their clinical significance : Comparison regarding KRAS mutation

BACKGROUND

Colorectal cancer (CRC) is among the most widespread malignancies in the world. MicroRNA (miRNA) has been identified as an important modulator of the biological processes of the cells. This group of noncoding RNAs also has a pivotal function in the growth and development of human cancers, including CRC. Among these miRNAs, miR-196, miR-132, miR-146a, and miR-134 have fundamental impacts on the regulation of cancers. The current study aimed to investigate the involvement of these miRNAs in CRC patients.

METHODS

In this study, 50 pairs of tumor and tumor margin samples of CRC patients were investigated to assess the expression levels of miR-196, miR-132, miR-146a, and miR-134 in this cancer. For this purpose, firstly, quantitative real-time PCR (qRT-PCR) was applied. Also, KRAS mutation and clinicopathological characteristics of the CRC patients were analyzed in the study groups.

RESULTS

The findings demonstrated the overexpression of miR-196 (P-value = 0.0045) and miR-146a (P-value = 0.0033) in tumor tissues compared to controls. Conversely, the expression levels of miR-132 (P-value = 0.00032) and miR-134 (P-value < 0.0001) were downregulated in tumor tissues. Also, miR-146a was the only miRNA with significant expression change in the case of the KRAS gene mutation. Interestingly, the expression ratio of these miRNAs was significantly associated with some of the clinicopathological features of the patients, such as lymph node and distant metastases.

CONCLUSION

Our data demonstrated that these miRNAs appear to be promising novel biomarkers for early diagnosis of CRC and may pave the way for the future establishment of novel therapeutic options for CRC.

Serum angiogenin as a potential biomarker for early detection of colorectal adenomas and colorectal cancer

Although colorectal cancer (CRC) is one of the most common causes of cancer mortality, early-stage detection dramatically improves survival rate. To explore the feasibility of serum angiogenin (ANG) as a biomarker for early detection of colorectal neoplasia, we collected serum samples from 781 participants, including 369 patients with CRC, 133 with colorectal adenoma and 279 healthy controls. We examined the levels of serum ANG by ELISA, calculated the diagnostic accuracy of ANG by plotted receiver operating characteristic curves (ROCs), and compared it with those obtained by carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9). We also analyzed the relationship between serum ANG level and TNM stage in CRC patients. The results showed that ANG serum levels were significantly elevated in patients with colorectal adenomas and CRC (P < 0.01). The area under the ROC curve (AUC) for ANG in distinguishing CRC patients from healthy controls was 0.740 [95% confidence interval (CI): 0.705-0.744], comparable to that of CEA (0.770; 95% CI: 0.735-0.802; P = 0.26) but significantly higher than that of CA19-9 (0.636; 95% CI: 0.598-0.674, P < 0.01), with much higher sensitivity (67.75%) than CEA (36.86%) or CA19-9 (12.20%). We observed no significant differences in ANG serum levels among CRCs at different TNM stages. Furthermore, sensitivity and specificity of ANG for distinguishing colorectal adenomas patients from healthy controls were 66.20% and 64.90%, respectively. ANG has the potential to serve as a serum biomarker for early detection of colorectal neoplasia.

Expression and prognostic significance of CBX2 in colorectal cancer: database mining for CBX family members in malignancies and vitro analyses

Background

The Chromobox (CBX) domain protein family, a core component of polycomb repressive complexes 1, is involved in transcriptional repression, cell differentiation, and program development by binding to methylated histone tails. Each CBX family member plays a distinct role in various biological processes through their own specific chromatin domains, due to differences in conserved sequences of the CBX proteins. It has been demonstrated that colorectal cancer (CRC) is a multiple-step biological evolutionary process, whereas the roles of the CBX family in CRC remain largely unclear.

Methods

In the present study, the expression and prognostic significance of the CBX family in CRC were systematically analyzed through a series of online databases, including Cancer Cell Line Encyclopedia (CCLE), Oncomine, Human Protein Atlas (HPA), and Gene Expression Profiling Interactive Analysis (GEPIA). For in vitro verification, we performed cell cloning, flow cytometry and transwell experiments to verify the proliferation and invasion ability of CRC cells after knocking down CBX2.

Results

Most CBX proteins were found to be highly expressed in CRC, but only the elevated expression of CBX2 could be associated with poor prognosis in patients with CRC. Further examination of the role of CBX2 in CRC was performed through several in vitro experiments. CBX2 was overexpressed in CRC cell lines via the CCLE database and the results were verified by RT-qPCR. Moreover, the knockdown of CBX2 significantly suppressed CRC cell proliferation and invasion. Furthermore, the downregulation of CBX2 was found to promote CRC cell apoptosis.

Conclusions

Based on these findings, CBX2 may function as an oncogene and potential prognostic biomarker. Thus, the association between the abnormal expression of CBX2 and the initiation of CRC deserves further exploration.

Systems-level biomarkers identification and drug repositioning in colorectal cancer

Colorectal cancer (CRC) is the most commonly diagnosed fatal cancer in both women and men worldwide. CRC ranked second in mortality and third in incidence in 2020. It is difficult to diagnose CRC at an early stage as there are no clinical symptoms. Despite advances in molecular biology, only a limited number of biomarkers have been translated into routine clinical practice to predict risk, prognosis and response to treatment. In the last decades, systems biology approaches at the omics level have gained importance. Over the years, several biomarkers for CRC have been discovered in terms of disease diagnosis and prognosis. On the other hand, a few drugs are being developed and used in clinics for the treatment of CRC. However, the development of new drugs is very costly and time-consuming as the research and development takes about 10 years and more than $1 billion. Therefore, drug repositioning (DR) could save time and money by establishing new indications for existing drugs. In this review, we aim to provide an overview of biomarkers for the diagnosis and prognosis of CRC from the systems biology perspective and insights into DR approaches for the prevention or treatment of CRC.

CD4+ Memory Stem T Cell in Peripheral Blood: A Promising Immune Index for Early Screening and Auxiliary Diagnosis of Colorectal Cancer

Background and Aims

Colorectal cancer (CRC) lacks obvious symptoms in the early stage of the disease, making it is easy to be misdiagnosed and remain undetected. Here, we explored the role of CD4⁺ memory stem T cells (TSCM) in peripheral blood in the early screening and auxiliary diagnosis of CRC.

Materials and Methods

Patients diagnosed with a “colorectal mass” by colonoscopy, at the Dongyang People’s Hospital (Zhejiang, China), between November 2020 and June 2021, were included in this prospective study. Using histopathological results as the gold standard for diagnosis, patients were divided into “CRC group” and “benign tumor group”. Healthy volunteers were recruited as “healthy controls.” Ten-color flow cytometry was used to detect CD4⁺ T cell subsets, and the results were analyzed using the Kaluza software. Carcinoembryonic antigen (CEA) and carbohydrate antigen 199 (CA199) were detected by the Roche Cobas e 602 electrochemiluminescence immunoassay analyzer.

Results

This study involved 33 patients with CRC, 41 patients with colorectal benign tumors, and 49 healthy volunteers. The absolute value and frequency of CD4⁺ TSCM can clearly distinguish colorectal cancer, benign tumors, and healthy controls. According to the area under the receiver operating characteristic curve (AUC), the absolute value of CD4⁺ TSCM used to assist in the diagnosis of CRC was 0.758 (sensitivity: 0.612; specificity: 0.788), which is higher than the values for CEA (AUC: 0.707) and CA199 (AUC: 0.552). In early screening, the sensitivity of the absolute value of CD4⁺ TSCM (sensitivity: 0.612) was significantly higher than that of CEA (sensitivity: 0.333) and CA199 (sensitivity: 0.259).

Conclusion

CD4⁺ TSCM in peripheral blood may be a promising immune index for the early screening and auxiliary diagnosis of CRC.

Beyond Colonoscopy: Exploring New Cell Surface Biomarkers for Detection of Early, Heterogenous Colorectal Lesions

Colorectal cancer (CRC) is the third leading cause of cancer-related deaths among both men and women in the United States. Early detection and surgical removal of high-risk lesions in the colon can prevent disease from developing and spreading. Despite implementation of programs aimed at early detection, screening colonoscopies fail to detect a fraction of potentially aggressive colorectal lesions because of their location or nonobvious morphology. Optical colonoscopies, while highly effective, rely on direct visualization to detect changes on the surface mucosa that are consistent with dysplasia. Recent advances in endoscopy techniques and molecular imaging permit microscale visualization of the colonic mucosa. These technologies can be combined with various molecular probes that recognize and target heterogenous lesion surfaces to achieve early, real-time, and potentially non-invasive, detection of pre-cancerous lesions. The primary goal of this review is to contextualize existing and emergent CRC surface biomarkers and assess each’s potential as a candidate marker for early marker-based detection of CRC lesions. CRC markers that we include were stratified by the level of support gleaned from peer-reviewed publications, abstracts, and databases of both CRC and other cancers. The selected biomarkers, accessible on the cell surface and preferably on the luminal surface of the colon tissue, are organized into three categories: (1) established biomarkers (those with considerable data and high confidence), (2) emerging biomarkers (those with increasing research interest but with less supporting data), and (3) novel candidates (those with very recent data, and/or supportive evidence from other tissue systems). We also present an overview of recent advances in imaging techniques useful for visual detection of surface biomarkers, and discuss the ease with which these methods can be combined with microscopic visualization.

Personalized Therapy and Liquid Biopsy-A Focus on Colorectal Cancer

(1) Background: Resistance mechanisms represent a barrier to anti-cancer therapies. Liquid biopsies would allow obtaining additional information in order to develop targeted therapies to thwart the resistance phenomena but also to follow in time real response to treatment and be able to adapt it the most quickly possible way in case of resistance. (2) Methods: herein we summarize the different liquid biopsies which are currently under research; we then review the literature and focalize on one of their potential roles: the theranostic one and especially in the cases of colorectal cancers. (3) Results: few studies targeting liquid biopsy as a potential tool to adapt cancer treatments are present in the literature and encompass few patients. (4) Conclusions: further research is needed to prove the efficiency of LB. Indeed, it seems a promising tool to guide treatment by targeting actionable mutations with detection of resistant mutations.

Selective in vitro cytotoxicity effect of Drimia calcarata bulb extracts against p53 mutant HT-29 and p53 wild-type Caco-2 colorectal cancer cells through STAT5B regulation

Colorectal cancer is the fourth leading cause of oncological-related deaths and the third most diagnosed malignancy, worldwide. The emergence of chemoresistance is a fundamental drawback of colorectal cancer therapies and there is an urgent need for novel plant-derived therapeutics. In this regard, other compounds are needed to improve the efficacy of treatment against colorectal cancer. Medicinal plants have been effectively used by traditional doctors for decades to treat various ailments with little to no side effects. Drimia calcarata (D. calcarata) is one of the plants used by Pedi people in South Africa to treat a plethora of ailments. However, the anticancer therapeutic use of D. calcarata is less understood. Thus, this study was aimed at evaluating the potential anticancer activities of D. calcarata extracts against human colorectal cancer cells. The phytochemical analysis and antioxidant activity were analysed using LC-MS, DPPH, and FRAP. The inhibitory effects and IC50 values of D. calcarata extracts were determined using the MTT assay. Induction of cellular apoptosis was assessed using fluorescence microscopy, the Muse® Cell Analyser, and gene expression analysis by Polymerase Chain Reaction (PCR). Water extract (WE) demonstrated high phenolic, tannin, and flavonoid contents than the methanol extract (ME). LC-MS data demonstrated strong differences between the ME and WE. Moreover, WE showed the best antioxidant activity than ME. The MTT data showed that both ME and WE had no significant activity against human embryonic kidney Hek 293 cell line that served as non-cancer control cells. Caco-2 cells demonstrated high sensitivity to the ME and demonstrated resistance toward the WE, while HT-29 cells exhibited sensitivity to both D. calcarata extracts. The expression of apoptosis regulatory genes assessed by PCR revealed an upregulation of p53 by ME, accompanied by downregulation of Bcl-2 and high expression of Bax after treatment with curcumin. The Bax gene was undetected in HT-29 cells. The methanol extract induced mitochondrial-mediated apoptosis in colorectal Caco-2 and HT-29 cells and WE induced the extrinsic apoptotic pathway in HT-29 cells. ME downregulated STAT1, 3, and 5B in HT-29 cells. The D. calcarata bulb extracts, therefore, contain potential anticancer agents that can be further targeted for cancer therapeutics.

miRNA Clusters with Up-Regulated Expression in Colorectal Cancer

Simple Summary

As miRNAs show the capacity to be used as CRC biomarkers, we analysed experimentally validated data about frequently up-regulated miRNA clusters in CRC tissue. We identified 15 clusters that showed increased expression in CRC: miR-106a/363, miR-106b/93/25, miR-17/92a-1, miR-181a-1/181b-1, miR-181a-2/181b-2, miR-181c/181d, miR-183/96/182, miR-191/425, miR-200c/141, miR-203a/203b, miR-222/221, mir-23a/27a/24-2, mir-29b-1/29a, mir-301b/130b and mir-452/224. Cluster positions in the genome are intronic or intergenic. Most clusters are regulated by several transcription factors, and by long non-coding RNAs. In some cases, co-expression of miRNA with other cluster members or host gene has been proven. miRNA expression patterns in cancer tissue, blood and faeces were compared. The members of the selected clusters target 181 genes. Their functions and corresponding pathways were revealed with the use of Panther analysis. Clusters miR-17/92a-1, miR-106a/363, miR-106b/93/25 and miR-183/96/182 showed the strongest association with metastasis occurrence and poor patient survival, implicating them as the most promising targets of translational research.

Abstract

Colorectal cancer (CRC) is one of the most common malignancies in Europe and North America. Early diagnosis is a key feature of efficient CRC treatment. As miRNAs can be used as CRC biomarkers, the aim of the present study was to analyse experimentally validated data on frequently up-regulated miRNA clusters in CRC tissue and investigate their members with respect to clinicopathological characteristics of patients. Based on available data, 15 up-regulated clusters, miR-106a/363, miR-106b/93/25, miR-17/92a-1, miR-181a-1/181b-1, miR-181a-2/181b-2, miR-181c/181d, miR-183/96/182, miR-191/425, miR-200c/141, miR-203a/203b, miR-222/221, mir-23a/27a/24-2, mir-29b-1/29a, mir-301b/130b and mir-452/224, were selected. The positions of such clusters in the genome can be intronic or intergenic. Most clusters are regulated by several transcription factors, and miRNAs are also sponged by specific long non-coding RNAs. In some cases, co-expression of miRNA with other cluster members or host gene has been proven. miRNA expression patterns in cancer tissue, blood and faeces were compared. Based on experimental evidence, 181 target genes of selected clusters were identified. Panther analysis was used to reveal the functions of the target genes and their corresponding pathways. Clusters miR-17/92a-1, miR-106a/363, miR-106b/93/25 and miR-183/96/182 showed the strongest association with metastasis occurrence and poor patient survival, implicating them as the most promising targets of translational research.

Biomarkers (mRNAs and Non-Coding RNAs) for the Diagnosis and Prognosis of Colorectal Cancer - From the Body Fluid to Tissue Level

In recent years, the diagnosis and treatment of colorectal cancer (CRC) have been continuously improved, but the mortality rate continues to be high, especially in advanced patients. CRC patients usually have no obvious symptoms in the early stage and are already in the advanced stage when they are diagnosed. The 5-year survival rate is only 10%. The blood markers currently used to screen for CRC, such as carcinoembryonic antigen and carbohydrate antigen 19-9, have low sensitivity and specificity, whereas other methods are invasive or too expensive. As a result, recent research has shifted to the development of minimally invasive or noninvasive biomarkers in the form of body fluid biopsies. Non-coding RNA molecules are composed of microRNAs, long non-coding RNAs, small nucleolar RNAs, and circular RNAs, which have important roles in the occurrence and development of diseases and can be utilized for the early diagnosis and prognosis of tumors. In this review, we focus on the latest findings of mRNA-ncRNA as biomarkers for the diagnosis and prognosis of CRC, from fluid to tissue level.

Towards Novel Non-Invasive Colorectal Cancer Screening Methods: A Comprehensive Review

Colorectal cancer (CRC) is one of the leading cancer-related causes of death in the world. Since the 70s, many countries have adopted different CRC screening programs, which has resulted in a decrease in mortality. However, current screening test options still present downsides. The commercialized stool-based tests present high false-positive rates and low sensitivity, which negatively affects the detection of early stage carcinogenesis. The gold standard colonoscopy has low uptake due to its invasiveness and the perception of discomfort and embarrassment that the procedure may bring. In this review, we collected and described the latest data about alternative CRC screening techniques that can overcome these disadvantages. Web of Science and PubMed were employed as search engines for studies reporting on CRC screening tests and future perspectives. The searches generated 555 articles, of which 93 titles were selected. Finally, a total of 50 studies, describing 14 different CRC alternative tests, were included. Among the investigated techniques, the main feature that could have an impact on CRC screening perception and uptake was the ease of sample collection. Urine, exhaled breath, and blood-based tests promise to achieve good diagnostic performance (sensitivity of 63-100%, 90-95%, and 47-97%, respectively) while minimizing stress and discomfort for the patient.

IL-8, MSPa, MIF, FGF-9, ANG-2 and AgRP collection were identified for the diagnosis of colorectal cancer based on the support vector machine model

Colorectal cancer (CRC) is one of the most common cancer, and the early detection of CRC is essential to improve the survival rate of patients. To identify diagnostic markers for colorectal cancer (CRC) by screening differentially expressed proteins (DEPs) in CRC. The DEPs were initially obtained from 12 CRC samples and 12 healthy control samples, and verification analysis was performed in another 34 CRC samples and 34 normal controls. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment with DEPs was analyzed by the R package clusterProfiler (Version 3.2.11), and the DEP-associated protein-protein interaction (PPI) network was created from the STRING database. Additionally, Support Vector Machine (SVM) model prediction and survival analyses were conducted on the key DEPs. Preliminary screening and functional analysis showed that the DEPs mainly overrepresented in pathways such as cytokine-cytokine receptor interaction, chemokine signaling pathway, Rap1, Ras, and MAPK signaling pathways. The key DEPs, including AgRP, ANG-2, Dtk, EOT3, FGF-4, FGF-9, HCC-4, IL-16, IL-8, MIF, MSPa, TECK, TPO, TRAIL R3, and VEGF-D, were used to construct a custom chip. The drug-gene interaction network suggested that TPO was a key drug target. ROC curve showed the SVM diagnostic model with the DEPs IL-8, MSPa, MIF, FGF-9, ANG-2, and AgRP had better diagnostic performance with an AUC of 0.933. Survival analysis showed the expression of FGF9, TPO, TRAIL R3, Dtk, TECK and FGF4 were associated with prognosis. This study revealed the important serum proteins in the pathogenesis of CRC, which might serve as useful and noninvasive predictors for the diagnosis of CRC.

Electrochemical biosensors for measurement of colorectal cancer biomarkers

Colorectal cancer (CRC) is associated with one of the highest rates of mortality among cancers worldwide. The early detection and management of CRC is imperative. Biomarkers play an important role in CRC screening tests, CRC treatment, and prognosis and clinical management; thus rapid and sensitive detection of biomarkers is helpful for early detection of CRC. In recent years, electrochemical biosensors for detecting CRC biomarkers have been widely investigated. In this review, different electrochemical detection methods for CRC biomarkers including immunosensors, aptasensors, and genosensors are summarized. Further, representative examples are provided that demonstrate the advantages of electrochemical sensors modified by various nanomaterials. Finally, the limitations and prospects of biomarkers and electrochemical sensors in detection are also discussed. Graphical abstract.

Transcriptional dysregulation of TRIM29 promotes colorectal cancer carcinogenesis via pyruvate kinase-mediated glucose metabolism

Targeted molecular therapy is the most effective treatment for cancer. An effective therapeutic target for colorectal cancer (CRC) is urgently needed. However, the mechanisms of CRC remain poorly understood, which has hampered research and development of CRC-targeted therapy. TRIM29 is a ubiquitin E3 ligase that has been reported as an oncogene in several human tumors. In this study, we show that increased levels of TRIM29 were detected in CRC compared with normal tissues and were associated with poor clinical outcome, advanced stage and lymph node metastasis, particularly those with right-sided colorectal cancer (RSCC). Notably, GATA2 (GATA Binding Protein 2) transcriptionally repressed TRIM29 expression. The loss of GATA2 and high expression of TRIM29 occur more frequently in RSCC than in left-sided colorectal cancer (LSCC). Functional assays revealed that TRIM29 promotes the malignant CRC phenotype in vitro and in vivo. Mechanistic analyses indicate that TRIM29 promotes pyruvate kinase (mainly PKM1) degradation via the ubiquitin-proteasome pathway. TRIM29 directly targets PKM1 to reduce PKM1/PKM2 ratio, which results in PKM2-mediated aerobic glycolysis (Warburg effect) acting as the dominant energy source in CRC. Our findings suggest that TRIM29 acts as a tumor promoter in CRC, especially in RSCC, and is a potential therapeutic target for CRC treatment.

Selection and characterisation of Affimers specific for CEA recognition

Carcinoembryonic antigen (CEA) is the only blood based protein biomarker at present, used for preoperative screening of advanced colorectal cancer (CRC) patients to determine the appropriate curative treatments and post-surveillance screening for tumour recurrence. Current diagnostics for CRC detection have several limitations and development of a highly sensitive, specific and rapid diagnostic device is required. The majority of such devices developed to date are antibody-based and suffer from shortcomings including multimeric binding, cost and difficulties in mass production. To circumvent antibody-derived limitations, the present study focused on the development of Affimer proteins as a novel alternative binding reagent for CEA detection. Here, we describe the selection, from a phage display library, of Affimers specific to CEA protein. Characterization of three anti-CEA Affimers reveal that these bind specifically and selectively to protein epitopes of CEA from cell culture lysate and on fixed cells. Kinetic binding analysis by SPR show that the Affimers bind to CEA with high affinity and within the nM range. Therefore, they have substantial potential for used as novel affinity reagents in diagnostic imaging, targeted CRC therapy, affinity purification and biosensor applications.

Selective expression of KCNA5 and KCNB1 genes in gastric and colorectal carcinoma

Background

Gastric and colorectal cancers are the most common malignant tumours, leading to a significant number of cancer-related deaths worldwide. Recently, increasing evidence has demonstrated that cancer cells exhibit a differential expression of potassium channels and this can contribute to cancer progression. However, their expression and localisation at the somatic level remains uncertain. In this study, we have investigated the expression levels of KCNB1 and KCNA5 genes encoding ubiquitous Kv2.1 and Kv1.5 potassium channels in gastric and colorectal tumours.

Methods

Gastric and colorectal tumoral and peritumoral tissues were collected to evaluate the expression of KCNB1 and KCNA5 mRNA by quantitative PCR. Moreover, the immunohistochemical staining profile of Kv2.1 and Kv1.5 was assessed on 40 Formalin-Fixed and Paraffin-Embedded (FFPE) gastric carcinoma tissues. Differences in gene expression between tumoral and peritumoral tissues were compared statistically with the Mann-Whitney U test. The association between the clinicopathological features of the GC patients and the expression of both Kv proteins was investigated with χ2 and Fisher’s exact tests.

Results

The mRNA fold expression of KCNB1 and KCNA5 genes showed a lower mean in the tumoral tissues (0.06 ± 0.17, 0.006 ± 0.009) compared to peritumoral tissues (0.08 ± 0.16, 0.16 ± 0.48, respectively) without reaching the significance rate (p = 0.861, p = 0.152, respectively). Interestingly, Kv2.1 and Kv1.5 immunostaining was detectable and characterised by a large distribution in peritumoral and tumoral epithelial cells. More interestingly, inflammatory cells were also stained. Surprisingly, Kv2.1 and Kv1.5 staining was undoubtedly and predominantly detected in the cytoplasm compartment of tumour cells. Indeed, the expression of Kv2.1 in tumour cells revealed a significant association with the early gastric cancer clinical stage (p = 0.026).

Conclusion

The data highlight, for the first time, the potential role of Kv1.5 and Kv2.1 in gastrointestinal-related cancers and suggests they may be promising prognostic markers for these tumours.

A Novel Prognostic Model Incorporating Carcinoembryonic Antigen in 3-Week or Longer Postoperative Period for Stage III Colon Cancer: A Multicenter Retrospective Study

Background

The prognostic stratification of colon cancer using only the tumor-node-metastasis (TNM) stage has some limitations. We sought to increase the accuracy of stratifying patients with stage III colon cancer by constructing a prognostic model combining carcinoembryonic antigen (CEA) with TNM.

Methods

We retrospectively analyzed the data generated from stage III colon cancer patients who had early postoperative CEA measurement from 21 to 100 days after surgery from 2006 to 2017. CEA value was processed using restricted cubic splines (RCS) method. The prognostic model was developed using cox proportional hazards regression.

Results

The time later than 20 days after surgery was optimal for measuring CEA, which was determined by comparing the prognostic value for preoperative and postoperative CEA (N = 2,049), and by evaluating the relationship between the hazard ratio (HR) and postoperative CEA measuring time. Postoperative CEA, T stage and N stage were selected into the final model, and the mean integrated-AUC (iAUC) was 0.78 with 1,000 × bootstrap resampling, which was higher than the model using only T and N stages (TN model; mean iAUC, 0.66). The net reclassification improvement (NRI) was 15% when compared with TN model. Patients could be divided into high and low risk groups by the model, and 3-year disease-free survival (DFS) were 53.7% and 87.0%, respectively (HR, 4.30; 95% CI, 2.65 to 6.96; P < 0.001). Similar results were found in the validation set.

Conclusions

Stage III colon cancer could be stratified more accurately using the new prognostic model combining postoperative CEA with T and N stage.

A Review of GC-Based Analysis of Non-Invasive Biomarkers of Colorectal Cancer and Related Pathways

Colorectal cancer (CRC) is the third most commonly diagnosed cancer in the world. In Europe, it is the second most common cause of cancer-related deaths. With the advent of metabolomics approaches, studies regarding the investigation of metabolite profiles related to CRC have been conducted, aiming to serve as a tool for early diagnosis. In order to provide further information about the current status of this field of research, 21 studies were systematically reviewed, regarding their main findings and analytical aspects. A special focus was given to the employment of matrices obtained non-invasively and the use of gas chromatography as the analytical platform. The relationship between the reported volatile and non-volatile biomarkers and CRC-related metabolic alterations was also explored, demonstrating that many of these metabolites are connected with biochemical pathways proven to be involved in carcinogenesis. The most commonly reported CRC indicators were hydrocarbons, aldehydes, amino acids and short-chain fatty acids. These potential biomarkers can be associated with both human and bacterial pathways and the analysis based on such species has the potential to be applied in the clinical practice as a low-cost screening method.

Glycoproteomic Analysis Reveals Aberrant Expression of Complement C9 and Fibronectin in the Plasma of Patients with Colorectal Cancer

Colorectal cancer (CRC) is a major cause of cancer mortality. Currently used CRC biomarkers provide insufficient sensitivity and specificity; therefore, novel biomarkers are needed to improve the CRC detection. Label-free quantitative proteomics were used to identify and compare glycoproteins, enriched by wheat germ agglutinin, from plasma of CRC patients and age-matched healthy controls. Among 189 identified glycoproteins, the levels of 7 and 15 glycoproteins were significantly altered in the non-metastatic and metastatic CRC groups, respectively. Protein-protein interaction analysis revealed that they were predominantly involved in immune responses, complement pathways, wound healing and coagulation. Of these, the levels of complement C9 (C9) was increased and fibronectin (FN1) was decreased in both CRC states in comparison to those of the healthy controls. Moreover, their levels detected by immunoblotting were validated in another independent cohort and the results were consistent with in the study cohort. Combination of CEA, a commercial CRC biomarker, with C9 and FN1 showed better diagnostic performance. Interestingly, predominant glycoforms associated with acetylneuraminic acid were obviously detected in alpha-2 macroglobulin, haptoglobin, alpha-1-acid glycoprotein 1, and complement C4-A of CRC patient groups. This glycoproteomic approach provides invaluable information of plasma proteome profiles of CRC patients and identification of CRC biomarker candidates.

Klotho (rs1207568 and rs564481) gene variants and colorectal cancer risk

BACKGROUND/AIMS

Whereas colorectal cancer (CRC) is the third most common cancer worldwide, klotho gene has been reported as a tumor suppressor gene. Therefore, the aim of this study was to investigate the association between klotho (rs1207568 and rs564481) variants and CRC in Egyptian patients.

MATERIALS AND METHODS

A case-control study comprising 100 patients with CRC and 100 age- and sex-matched healthy controls was conducted. Genotyping of klotho was performed by polymerase chain reaction with confronting two-pair primers.

RESULTS

The frequencies of the A allele of rs1207568 and the AC haplotype were significantly higher in patients with CRC than in the controls (p=0.019 and p=0.005, respectively).

CONCLUSION

We propose that klotho (rs1207568 and rs564481) variants play a significant role in colorectal carcinogenesis and that the klotho protein could be a target for oncotherapy.

Genomic profiling of microRNA target genes in colorectal cancer

Colorectal cancer is the second and third most common cancer in men and women, respectively, worldwide. Alterations such as genetic and epigenetic are common in colorectal cancer and are the basis of tumor formation. The exploration of the molecular basis of colorectal cancer can drive a better understanding of the disease as well as guide the prognosis, therapeutics, and disease management. This study is aimed at investigating the genetic mutation profile of five candidate microRNAs (hsa-miR-513b-3p, hsa-miR-500b-3p, hsa-miR-500a-3p, hsa-miR-450b-3p, hsa-miR-193a-5p) targeted by seven genes (APC, KRAS, TCF7L2, EGFR, IGF1R, CASP8, and GNAS)) using in silico approaches. Two datasets (dataset 1 from our previous study and dataset two (The Cancer Genome Atlas, Nature 2012) were considered for this study. Protein-protein interaction, expression analysis, and genetic profiling were carried out using STRING, FireBrowse, and cBioPortal, respectively. Protein-protein interaction network showed that epidermal growth factor receptor has the highest connection among the target genes and this can be considered as the hub gene. Relative to other solid tumors, in colorectal cancer, six of the target genes were downregulated and only CASP8 was upregulated. Genes with protein tyrosine kinases domain were frequently altered in colorectal cancer and the most common alteration in these genes/domain are missense mutation. These results could serve as a lead in the identification of driver genes responsible for colorectal cancer initiation and progression. However, the intense mechanism of these results remains unclear and further experimental validation and molecular approaches are the focal points in the nearest future.

Elevated soluble E-cadherin during the epithelial-mesenchymal transition process and as a diagnostic marker in colorectal cancer

Epithelial-mesenchymal transition (EMT) plays a crucial role in colorectal cancer (CRC) metastasis. Soluble E-cadherin (sE-cadherin) is a peptide degradation product of the E-cadherin, a key epithelial molecule of EMT. However, it is not known if elevated levels of sE-cadherin also occur during EMT. And the study of sE-cadherin in colorectal cancer is rare. The purpose of the study was to evaluate the relationship between sE-cadherin and EMT in CRC and to evaluate the diagnostic value of sE-cadherin as a serum marker for CRC. Transforming growth factor-β1 (TGF-β1) was used to induce EMT in HT29 and SW480 cells. The cells treated with TGF-β1 showed morphological and biological behavior changes consistent with EMT. Western blot and ELISA showed the levels of sE-cadherin were increased during EMT in CRC cells. In addition, we intravenously injected luciferase-labeled SW480 cells into nude mice to construct CRC metastasis model. Following the elongation of time, the fluorescence intensity of the experimental group was gradually increased. Correspondingly, the serum concentration of sE-cadherin also increased during CRC metastasis in mice. Furthermore, compared to healthy subjects, significantly higher levels of serum sE-cadherin were also observed in CRC patients and correlated with clinicopathological features. For discriminating CRC from healthy controls, the area under the receiver operating characteristic (ROC) curve (AUC) of sE-cadherin was 0.853, while the optimal cut-off point was set at 5928.16 ng/ml, the diagnostic sensitivity was 73.9% and the specificity was 80%. Compared with current commercial biomarkers (CEA, CA19-9 and CA125), the diagnostic performance of sE-cadherin was highest. Combined sE-cadherin and CEA raised the sensitivity to 82.4%. Serum sE-cadherin level can be used as a potential diagnostic biomarker of CRC.

Endoglin (CD105) and VEGF as potential angiogenic and dissemination markers for colorectal cancer

Background

Colorectal cancer (CRC) is an important current problem concerning public health due to its high incidence and mortality. Advances in molecular and cellular knowledge and the detection of new disease biomarkers are very important to improve prognosis, prediction, and early diagnosis. In this study, we aimed to analyze the gene and protein expression levels of two angiogenic markers, VEGF and soluble Endoglin, during different tumor stages as well as at different stages of cancer treatment, to predict the diagnosis and evolution of colon and rectal cancer.

Material and methods

This study includes 133 CRC patients (93 with colon cancer and 40 with rectal cancer) on which the gene and protein expression of Endoglin (membrane and soluble form) and VEGF were analyzed by molecular and immunohistochemical techniques on different tumor stage samples and plasma obtained preoperatively as well as 3, 6, and 9 months after resection of the tumor.

Results

VEGF and Endoglin gene expressions were higher in tumor tissue than in surrounding non-tumoral tissue for both types of cancer. The VEGF levels in plasma were found to decrease in less aggressive tumors, whereas soluble Endoglin was increased in preoperative samples of patients with metastasis. Membrane Endoglin expression was higher on the vascular endothelium of more aggressive tumors. In contrast, Endoglin expression was mainly in the colon epithelium in less aggressive stage tumors.

Conclusion

Endoglin and VEGF are proteins with a major role in the tumor angiogenesis process. This study performed with a wide cohort of human samples shows that both proteins seem to be valuable biomarkers in the diagnosis and prognosis of CRC.

Monoamine Oxidase B Expression Correlates with a Poor Prognosis in Colorectal Cancer Patients and Is Significantly Associated with Epithelial-to-Mesenchymal Transition-Related Gene Signatures

Monoamine oxidases (MAOs) including MAOA and MAOB are enzymes located on the outer membranes of mitochondria, which are responsible for catalyzing monoamine oxidation. Recently, increased level of MAOs were shown in several cancer types. However, possible roles of MAOs have not yet been elucidated in the progression and prognosis of colorectal carcinoma (CRC). We therefore analyzed the importance of MAOs in CRC by an in silico analysis and tissue microarrays. Several independent cohorts indicated that high expression of MAOB, but not MAOA, was correlated with a worse disease stage and poorer survival. In total, 203 colorectal adenocarcinoma cases underwent immunohistochemical staining of MAOs, and associations with clinicopathological parameters and patient outcomes were evaluated. We found that MAOB is highly expressed in CRC tissues compared to normal colorectal tissues, and its expression was significantly correlated with a higher recurrence rate and a poor prognosis. Moreover, according to the univariate and multivariate analyses, we found that MAOB could be an independent prognostic factor for overall survival and disease-free survival, and its prognostic value was better than T and N stage. Furthermore, significant positive and negative correlations of MAOB with mesenchymal-type and epithelial-type gene expressions were observed in CRC tissues. According to the highlighted characteristics of MAOB in CRC, MAOB can be used as a novel indicator to predict the progression and prognosis of CRC patients.