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Background: Emerging evidence supports tumor tissue-based comprehensive genomic profiling (CGP) in metastatic colorectal cancer (mCRC). Data on liquid biopsy-based circulating tumor DNA (ctDNA) CGP are scarce and mainly retrospective. Prospective comparison between the two tests is not currently available., Materials and Methods: The CAPRI 2-GOIM trial investigates efficacy and safety of ctDNA-driven, cetuximab-based sequence of three treatment lines in patients with RAS/BRAF V600E wild-type (WT) mCRC, as determined by the local laboratory. Before first-line therapy, CGP is carried out with FoundationOne (F1) CDx and F1 Liquid (F1L) CDx (324 genes) on tumor tissue DNA and plasma ctDNA, respectively., Results: For 2/207 (0.96%) patients, no ctDNA was detected by F1L CDx. No patient displayed tumor fraction (TF) below 1%, whereas elevated ctDNA (TF ≥ 10%) was detected among 140/205 (68.3%) patients. One thousand and thirteen genomic variants were identified. F1L CDx found KRAS, NRAS, or BRAF V600E alterations in 19 patients, whose tumors were classified as RAS/BRAF V600E WT by the local laboratory. Both F1 CDx and F1L CDx were available for 164/205 (80%) patients. A concordance of 61.4% between the two tests was observed. The concordance increased to 72.7% for F1L CDx with TF ≥ 10%. Concordance for genes potentially involved in anti-epidermal growth factor receptor resistance was found in 137/164 (83%) patients, increasing to 91.5% for F1L CDx with TF ≥ 10%. A higher number of genomic alterations was detected by F1L CDx compared with F1 CDx, including six cases with KRAS and NRAS alterations. Overall, 109/205 (53.2%) patients displayed at least one actionable genomic alteration (I to IIIB), according to the European Society for Medical Oncology Scale for Clinical Actionability of Molecular Targets (ESCAT)., Conclusion: Baseline liquid biopsy-based CGP is feasible, has high concordance with tumor tissue-based CGP, could better recapitulate tumor heterogeneity, and is clinically informative by identifying additional actionable genomic alterations in approximately half of RAS/BRAF V600E WT mCRC patients., (Copyright © 2024 European Society for Medical Oncology. Published by Elsevier Ltd. All rights reserved.)

Colorectal cancer (CRC) ranks third in terms of cancer incidence worldwide and is responsible for 8% of all deaths globally. Approximately 10% of CRC cases are caused by inherited pathogenic mutations in driver genes involved in pathways that are crucial for CRC tumorigenesis and progression. These hereditary mutations significantly increase the risk of initial benign polyps or adenomas developing into cancer. In recent years, the rapid and accurate sequencing of CRC-specific multigene panels by next-generation sequencing (NGS) technologies has enabled the identification of several recurrent pathogenic variants with established functional consequences. In parallel, rare genetic variants that are not characterized and are, therefore, called variants of uncertain significance (VUSs) have also been detected. The classification of VUSs is a challenging task because each amino acid has specific biochemical properties and uniquely contributes to the structural stability and functional activity of proteins. In this scenario, the ability to computationally predict the effect of a VUS is crucial. In particular, in silico prediction methods can provide useful insights to assess the potential impact of a VUS and support additional clinical evaluation. This approach can further benefit from recent advances in artificial intelligence-based technologies. In this review, we describe the main in silico prediction tools that can be used to evaluate the structural and functional impact of VUSs and provide examples of their application in the analysis of gene variants involved in hereditary CRC syndromes.

Introduction: Endoscopic submucosal dissection (ESD) is a widely used technique to remove early neoplastic lesions. It was primarily used in the initial days to treat gastric lesions, but recently, the horizon of this endoscopic procedure has expanded, which has allowed us to manage other technically more complex locations, such as the colorectum., Areas Covered: There has been an exponential growth regarding the wide range of devices available in the market for performing colorectal ESD. As a result, the aim of this review is to highlight the indication of this endoscopic technique, which device is best suited for which indication, as well as future trajectories in this field., Expert Opinion: Although some devices have proven to be more advantageous than others in this area, very often the choice is still subjective, which is commonly attributed to individual preferences and experience. However, an accurate knowledge of the available tools and their functioning, with their pros and cons, is fundamental for any endoscopist venturing into the field of third space endoscopy. In this way, one can choose which device best suits a particular situation, along with simultaneously having the wealth of knowledge related to therapeutic armamentarium at our disposal in the endoscopy suite.

Pinin (PNN) is a desmosome-associated protein that reinforces the organization of keratin intermediate filaments and stabilizes the anchoring of the cytoskeleton network to the lateral surface of the plasma membrane. The aberrant expression of PNN affects the strength of cell adhesion as well as modifies the intracellular signal transduction pathways leading to the onset of CRC. In our previous studies, we characterized the role of miR-195-5p in the regulation of desmosome junctions and in CRC progression. Here, with the aim of investigating additional mechanisms related to the desmosome complex, we identified PNN as a miR-195-5p putative target. Using a public data repository, we found that PNN was a negative prognostic factor and was overexpressed in colon cancer tissues from stage 1 of the disease. Then, we assessed PNN expression in CRC tissue specimens, confirming the overexpression of PNN in tumor sections. The increase in intracellular levels of miR-195-5p revealed a significant decrease in PNN at the mRNA and protein levels. As a consequence of PNN regulation by miR-195-5p, the expression of KRT8 and KRT19, closely connected to PNN, was affected. Finally, we investigated the in vivo effect of miR-195-5p on PNN expression in the colon of AOM/DSS-treated mice. In conclusion, we have revealed a new mechanism driven by miR-195-5p in the regulation of desmosome components, suggesting a potential pharmacological target for CRC therapy.

Background: Literature suggests colonic resection and primary anastomosis (RPA) instead of Hartmann's procedure (HP) for the treatment of left-sided colonic emergencies. We aim to evaluate the surgical options globally used to treat patients with acute left-sided colonic emergencies and the factors that leading to the choice of treatment, comparing HP and RPA., Methods: This is a prospective, international, multicenter, observational study registered on ClinicalTrials.gov. A total 1215 patients with left-sided colonic emergencies who required surgery were included from 204 centers during the period of March 1, 2020, to May 31, 2020. with a 1-year follow-up., Results: 564 patients (43.1%) were females. The mean age was 65.9 ± 15.6 years. HP was performed in 697 (57.3%) patients and RPA in 384 (31.6%) cases. Complicated acute diverticulitis was the most common cause of left-sided colonic emergencies (40.2%), followed by colorectal malignancy (36.6%). Severe complications (Clavien-Dindo ≥ 3b) were higher in the HP group (P < 0.001). 30-day mortality was higher in HP patients (13.7%), especially in case of bowel perforation and diffused peritonitis. 1-year follow-up showed no differences on ostomy reversal rate between HP and RPA. (P = 0.127). A backward likelihood logistic regression model showed that RPA was preferred in younger patients, having low ASA score (≤ 3), in case of large bowel obstruction, absence of colonic ischemia, longer time from admission to surgery, operating early at the day working hours, by a surgeon who performed more than 50 colorectal resections., Conclusions: After 100 years since the first Hartmann's procedure, HP remains the most common treatment for left-sided colorectal emergencies. Treatment's choice depends on patient characteristics, the time of surgery and the experience of the surgeon. RPA should be considered as the gold standard for surgery, with HP being an exception., (© 2024. The Author(s).)

Screening methods available for colorectal cancer (CRC) to date are burdened by poor reliability and low patient adherence and compliance. An altered pattern of volatile organic compounds (VOCs) in exhaled breath has been proposed as a non-invasive potential diagnostic tool for distinguishing CRC patients from healthy controls (HC). The aim of this study was to evaluate the reliability of an innovative portable device containing a micro-gas chromatograph in enabling rapid, on-site CRC diagnosis through analysis of patients' exhaled breath. In this prospective trial, breath samples were collected in a tertiary referral center of colorectal surgery, and analysis of the chromatograms was performed by the Biomedical Engineering Department. The breath of patients with CRC and HC was collected into Tedlar bags through a Nafion filter and mouthpiece with a one-way valve. The breath samples were analyzed by an automated portable gas chromatography device. Relevant volatile biomarkers and discriminant chromatographic peaks were identified through machine learning, linear discriminant analysis and principal component analysis. A total of 68 subjects, 36 patients affected by histologically proven CRC with no evidence of metastases and 32 HC with negative colonoscopies, were enrolled. After testing a training set (18 CRC and 18 HC) and a testing set (18 CRC and 14 HC), an overall specificity of 87.5%, sensitivity of 94.4% and accuracy of 91.2% in identifying CRC patients was found based on three VOCs. Breath biopsy may represent a promising non-invasive method of discriminating CRC patients from HC.

Desmosomes play a key role in the regulation of cell adhesion and signaling. Dysregulation of the desmosome complex is associated with the loss of epithelial cell polarity and disorganized tissue architecture typical of colorectal cancer (CRC). The aim of this study was to investigate and characterize the effect of miR-195-5p on desmosomal junction regulation in CRC. In detail, we proposed to investigate the deregulation of miR-195-5p and JUP , a gene target that encodes a desmosome component in CRC patients. JUP closely interacts with desmosomal cadherins, and downstream, it regulates several intracellular transduction factors. We restored the miR-195-5p levels by transient transfection in colonic epithelial cells to examine the effects of miR-195-5p on JUP mRNA and protein expression. The JUP regulation by miR-195-5p, in turn, determined a modulation of desmosome cadherins (Desmoglein 2 and Desmocollin 2). Furthermore, we focused on whether the miR-195-5p gain of function was also able to modulate the expression of key components of Wnt signaling, such as NLK, LEF1 and Cyclin D1. In conclusion, we have identified a novel mechanism controlled by miR-195-5p in the regulation of adhesive junctions, suggesting its potential clinical relevance for future miRNA-based therapy in CRC.

Colorectal cancer (CRC) is one of the leading causes of mortality for cancer in industrialized countries. The link between diet and CRC is well-known, and presumably CRC is the type of cancer which is most influenced by dietary habits. In Western countries, an inadequate dietary intake of fibers is endemic, and this could be a driving factor in the increase of CRC incidence. Indeed, several epidemiologic studies have elucidated an inverse relationship between daily fiber intake and risk of CRC. Long-term prognosis in CRC survivors is also dependent on dietary fibers. Several pathogenetic mechanisms may be hypothesized. Fibers may interfere with the metabolism of bile acids, which may promote colon carcinogenesis. Further, fibers are often contained in vegetables which, in turn, contain large amounts of antioxidant agents like resveratrol, polyphenols, or phytoestrogens. Moreover, fibers can be digested by commensal flora, thus producing compounds such as butyrate, which exerts an antiproliferative effect. Finally, fibers may modulate gut microbiota, whose composition has shown to be associated with CRC onset. In this regard, dietary interventions based on high-fiber-containing diets are ongoing to prevent CRC development, especially in patients with high potential for this type of tumor. Despite the fact that outcomes are preliminary, encouraging results have been observed.

Introduction: Artificial intelligence (AI) in gastrointestinal endoscopy includes systems designed to interpret medical images and increase sensitivity during examination. This may be a promising solution to human biases and may provide support during diagnostic endoscopy., Areas Covered: This review aims to summarize and evaluate data supporting AI technologies in lower endoscopy, addressing their effectiveness, limitations, and future perspectives., Expert Opinion: Computer-aided detection (CADe) systems have been studied with promising results, allowing for an increase in adenoma detection rate (ADR), adenoma per colonoscopy (APC), and a reduction in adenoma miss rate (AMR). This may lead to an increase in the sensitivity of endoscopic examinations and a reduction in the risk of interval-colorectal cancer. In addition, computer-aided characterization (CADx) has also been implemented, aiming to distinguish adenomatous and non-adenomatous lesions through real-time assessment using advanced endoscopic imaging techniques. Moreover, computer-aided quality (CADq) systems have been developed with the aim of standardizing quality measures in colonoscopy (e.g. withdrawal time and adequacy of bowel cleansing) both to improve the quality of examinations and set a reference standard for randomized controlled trials.

Colorectal cancer (CRC) is one of the deadliest forms of cancer worldwide. CRC development occurs mainly through the adenoma-carcinoma sequence, which can last decades, giving the opportunity for primary prevention and early detection. CRC prevention involves different approaches, ranging from fecal occult blood testing and colonoscopy screening to chemoprevention. In this review, we discuss the main findings gathered in the field of CRC chemoprevention, focusing on different target populations and on various precancerous lesions that can be used as efficacy evaluation endpoints for chemoprevention. The ideal chemopreventive agent should be well tolerated and easy to administer, with low side effects. Moreover, it should be readily available at a low cost. These properties are crucial because these compounds are meant to be used for a long time in populations with different CRC risk profiles. Several agents have been investigated so far, some of which are currently used in clinical practice. However, further investigation is needed to devise a comprehensive and effective chemoprevention strategy for CRC.

Background: A relevant number of adenomas can be missed during colonoscopy., Aims: Assess the current status of colonoscopy procedures in Italian centers., Methods: A prospective observational study involving 17 hospitals (34 endoscopists) included consecutive patients undergoing standard colonoscopy. In the first phase, endoscopists performed consecutive colonoscopies. In the second phase, retraining via an online learning platform was planned, while in the third phase data were collected analogously to phase 1., Results: A total of 3,504 patients were enrolled. Overall, a BBPS score ≥6 was obtained in 95.6% of cases (94.8% and 96.9% in the pre- and post-training phases, respectively). 88.4% of colonoscopies had a withdrawal time ≥6 min (88.2% and 88.7% in the pre- and post-training phases). Median adenoma detection rate (ADR) was 39.1%, with no significant differences between the pre- and post-training phases (40.1% vs 36.9%; P = 0.83). In total, 81% of endoscopists had a ADR performance above the 25% threshold., Conclusion: High colonoscopy quality standards are achieved by the Italian hospitals involved. Quality improvement initiatives and repeated module-based colonoscopy-training have been promoted in Italy during the last decade, which appear to have had a significant impact on quality colonoscopy metrics together with the activation of colorectal cancer screening programs., Competing Interests: Declaration of Competing Interest None to declare., (Copyright © 2022. Published by Elsevier Ltd.)

Background: The DNA mismatch repair (MMR) system is a highly preserved protein complex recognizing short insertions, short deletions, and single base mismatches during DNA replication and recombination. MMR protein status is identified using immunohistochemistry. Deficit in one or more MMR proteins, configuring deficient MMR status (dMMR), leads to frameshift mutations particularly clustered in microsatellite repeats. Thus, microsatellite instability (MSI) is the epiphenomenon of dMMR. In colorectal cancer (CRC), MMR/MSI status is a biomarker with prognostic and predictive value of resistance to 5-fluorouracil and response to immune checkpoint inhibitor therapy., Summary: In this Review, we describe the challenges the practicing pathologist may face in relation to the assessment of MMR/MSI status and any open issues which still need to be addressed, focusing on pre-analytic issues, pitfalls in the interpretation, and technical aspects of the different assays., Key Messages: The current methods of detecting dMMR/MSI status have been optimized for CRCs, and whether these techniques can be applied to all tumor and specimen types is still not fully understood. Following the Food and Drug Administration (FDA), tissue/site agnostic drug approval of pembrolizumab for advanced/metastatic MSI tumors, MMR/MSI status in gastrointestinal tract is a common request from the oncologist. In this setting, several issues still need to be addressed, including criteria for sample adequacy., (© 2023 S. Karger AG, Basel.)

Colorectal cancer (CRC) is among the best examples for depicting the relationship between inflammation and cancer. The introduction of new therapeutics targeting inflammatory mediators showed a marked decrease in the overall risk of CRC, although their chemopreventive potential is still debated. Specifically, a monoclonal antibody that blocks tumor necrosis factor (TNF), infliximab, increases CRC risk in inflammatory bowel disease patients. To address the axis between TNF and CRC development and progression, we depleted the Tnf from our previously established murine model of colitis-associated cancer (CAC), the Winnie- Apc Min/+ line. We characterized the new Winnie- APC Min/+- TNF-KO line through macroscopical and microscopical analyses. Surprisingly, the latter demonstrated that the deletion of Tnf in Winnie- Apc Min/+ mice resulted in an initial reduction in dysplastic lesion incidence in 5-week-old mice followed by a faster disease progression at 8 weeks. Histological data were confirmed by the molecular profiling obtained from both the real-time PCR analysis of the whole tissue and the RNA sequencing of the macrodissected tumoral lesions from Winnie- APC Min/+- TNF-KO distal colon at 8 weeks. Our results highlight that TNF could exert a dual role in CAC, supporting the promotion of neoplastic lesions onset in the early stage of the disease while inducing their reduction during disease progression.

Colorectal tumorigenesis is driven by alterations in genes and proteins responsible for cancer initiation, progression, and invasion. This multistage process is based on a dense network of protein-protein interactions (PPIs) that become dysregulated as a result of changes in various cell signaling effectors. PPIs in signaling and regulatory networks are known to be mediated by short linear motifs (SLiMs), which are conserved contiguous regions of 3-10 amino acids within interacting protein domains. SLiMs are the minimum sequences required for modulating cellular PPI networks. Thus, several in silico approaches have been developed to predict and analyze SLiM-mediated PPIs. In this review, we focus on emerging evidence supporting a crucial role for SLiMs in driver pathways that are disrupted in colorectal cancer (CRC) tumorigenesis and related PPI network alterations. As a result, SLiMs, along with short peptides, are attracting the interest of researchers to devise small molecules amenable to be used as novel anti-CRC targeted therapies. Overall, the characterization of SLiMs mediating crucial PPIs in CRC may foster the development of more specific combined pharmacological approaches.

Grape pomace (GP)-the major by-product of winemaking processes-still contains bioactive molecules with known beneficial properties for human health, such as an antiradical scavenging activity or an antiproliferative activity of tumors. In vitro studies have demonstrated that GP polyphenols specifically influence colon cancer cell proliferation. In addition to previously published work, we tested the phenolic compounds of Aglianico GP following an in vitro simulated gastrointestinal digestion on colorectal cancer cell lines at different degrees of differentiation. Our experiments, using HT29 and SW480 cells, confirmed the anti-proliferative effect of GP gastrointestinal digested extract and provided intriguing insights on the way it influences the cancer cell features (i.e., viability, proliferation, and apoptosis). We observed that Aglianico GP extract showed a great ability to affect cell proliferation and apoptosis. Interestingly, both HT29 and SW480 cells produced a significant increase in Bax, and a significant increase in the Bax/Bcl-2 ratio and caspase-3. The gastrointestinal digested GP extract was previously characterized both for antioxidant activity and phenolic composition. As a result, the TPC and the antioxidant activity reached high values in the Aglianico GP digested extract, and the main compounds assessed by UHPLC-DAD were anthocyanins, phenolic acids, and flavonoids. This work shed light on the use of digested GP extract as a dietary ingredient, a very sustainable source of nutritional compounds with potential health benefits for colon cancer cell proliferation.

Background: Current international guidelines strongly advise endoscopic submucosal dissection (ESD) instead of endoscopic mucosal resection (EMR) for the endoscopic resection of sessile colorectal tumours >20 mm., Aims: To compare the safety and efficacy of EMR and ESD for treating large non-invasive colorectal lesions., Material and Methods: We performed a systematic review using electronic databases (MEDLINE/PubMed, EMBASE, and Cochrane Library) on February 21st, 2021 and a meta-analysis to assess en-bloc and R0 rates, and related adverse events., Results: Twenty-four studies were included, comparing 3,424 ESD and 5,122 EMR procedures. The en-bloc resection rate was 90.8% in the ESD and 33.0% in the EMR group ( p  < .001). The R0 resection rate was 85.0% in the ESD and 64.6% in the EMR group ( p  = .005). The rate of perforation was 5.1% in the ESD and 1.67% in the EMR group ( p  < .001). The bleeding rate was 4.3% in the ESD and 3.6% in the EMR group ( p  = .008). The overall need for surgery, including oncologic reasons and complications, was 5.9% in the ESD and 3.1% in the EMR group ( p  < .001)., Conclusions: ESD for large non-pedunculated colorectal lesions allows a higher rate of R0 resections than EMR, at the cost of a higher perforation rate and the need for additional surgery.

The prognosis of locally advanced colorectal cancer (CRC) is currently unsatisfactory. This is mainly due to drug resistance, recurrence, and subsequent metastatic dissemination, which are sustained by the cancer stem cell (CSC) population. The main driver of the CSC gene expression program is Wnt signaling, and previous reports indicate that Wnt3a can activate p38 MAPK. Besides, p38 was shown to feed into the canonical Wnt/β-catenin pathway. Here we show that patient-derived locally advanced CRC stem cells (CRC-SCs) are characterized by increased expression of p38α and are "addicted" to its kinase activity. Of note, we found that stage III CRC patients with high p38α levels display reduced disease-free and progression-free survival. Extensive molecular analysis in patient-derived CRC-SC tumorspheres and APC Min/+ mice intestinal organoids revealed that p38α acts as a β-catenin chromatin-associated kinase required for the regulation of a signaling platform involved in tumor proliferation, metastatic dissemination, and chemoresistance in these CRC model systems. In particular, the p38α kinase inhibitor ralimetinib, which has already entered clinical trials, promoted sensitization of patient-derived CRC-SCs to chemotherapeutic agents commonly used for CRC treatment and showed a synthetic lethality effect when used in combination with the MEK1 inhibitor trametinib. Taken together, these results suggest that p38α may be targeted in CSCs to devise new personalized CRC treatment strategies.

Exosomes belong to the family of extracellular vesicles released by every type of cell both in normal and pathological conditions. Growing interest in studies indicates that extracellular vesicles, in particular, the fraction named exosomes containing lipids, proteins and nucleic acid, represent an efficient way to transfer functional cargoes between cells, thus combining all the other cell-cell interaction mechanisms known so far. Only a few decades ago, the involvement of exosomes in the carcinogenesis in different tissues was discovered, and very recently it was also observed how they carry and modulate the presence of Wnt pathway proteins, involved in the carcinogenesis of gastrointestinal tissues, such as Frizzled 10 protein (FZD10), a membrane receptor for Wnt. Here, we report the in vitro study on the capability of tumor-derived exosomes to induce neoplastic features in normal cells. Exosomes derived from two different colon cancer cell lines, namely the non-metastatic CaCo-2 and the metastatic SW620, were found to deliver, in both cases, FZD10, thus demonstrating the ability to reprogram normal colonic epithelial cell line (HCEC-1CT). Indeed, the acquisition of specific mesenchymal characteristics, such as migration capability and expression of FZD10 and markers of mesenchymal cells, was observed. The exosomes derived from the metastatic cell line, characterized by a level of FZD10 higher than the exosomes extracted from the non-metastatic cells, were also more efficient in stimulating EMT activation. The overall results suggest that FZD10, delivered by circulating tumor-derived exosomes, can play a relevant role in promoting the CRC carcinogenesis and propagation.

Objective: Polyphenols extracted by table grape have been demonstrated to decrease cell proliferation in vitro and to exert anti-atherosclerotic and antithrombotic activities, regulating cell functions. A grape polyphenolic profile is affected by climate as well as a grape cultivar. This study was aimed to characterize the berry skin polyphenolic composition, antioxidant activity and antiproliferative properties of two black grape cultivars, Autumn Royal and Egnatia., Methods: The phenolic composition of Grape Skin Extracts (GSEs) was determined by HPLC analyses. The antioxidant activity was determined using DPPH, ABTS and ORAC tests. Caco2, HT29 and SW480 human colon cancer cell lines were used to test the effects of GSEs in vitro. Cell proliferation and cell cycle were assessed with the MTT method and a Muse cell analyzer, respectively. qPCR and Western Blotting analysis were used to evaluate gene and protein expression, respectively., Results: The total polyphenolic content and the total antioxidant capacity were significantly higher in Autumn Royal than in Egnatia. However, table grape Egnatia showed greater ability to affect cell proliferation and apoptosis, as well as to exert a growth arrest in the S phase of the cell cycle, particularly in the Caco2 cell line., Conclusion: These data suggest that the new grape variety Egnatia is an interesting source of phenolic compounds that could be of interest in the food and pharmaceutical industries., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

The glycaemic index (GI) and glycaemic load (GL) are involved in the aetiology of different diseases, and they could be related to the development of colorectal cancer (CRC). The aim of this study was to evaluate the association between the quality and quantity indicators of carbohydrates consumed by the population of Córdoba (Argentina) and the odds of developing CRC in 2008-2016 period. A case-control study was conducted with 492 participants (161/331 cases/controls), interviewed through a validated FFQ. Multilevel logistic regression models were used to assess the effect of GI, GL and the quantity or weekly intake of high-GI foods on CRC occurrence, following adjustment for individual/first-level covariates, and using level of urbanisation as the contextual variable. The models were stratified by sex. Participants in the highest v. lowest tertile of dietary GL and weekly intake of high-GI foods had increased odds of CRC presence in the entire sample (OR 1·64, 95 % CI 1·16, 2·34 and OR 1·11, 95 % CI 1·09, 1·14, respectively) and in women (OR 1·98, 95 % CI 1·24, 3·18 and OR 1·41, 95 % CI 1·09, 1·83, respectively). In men, the second tertile of GL and weekly intake of high-GI foods were associated with CRC (OR 1·44, 95 % CI 1·04, 1·99 and OR 1·48, 95 % CI 1·32, 1·65, respectively). Also, GI was associated with CRC in women (highest v. lowest tertile OR 2·12, 95 % CI 1·38, 3·27). In addition to the quantity and quality of carbohydrates intake, it is important to consider the frequency of consumption of high-GI foods in CRC prevention.

Chronic inflammation increases the risk of developing certain types of cancer, such as colorectal cancer (CRC). The oxidative metabolism of polyunsaturated fatty acids (PUFAs) has a strong effect on colonic tumorigenesis and the levels of arachidonic acid (AA) and eicosapentaenoic acid (EPA) can contribute to the development of an inflammatory microenvironment. Aim of this study was to evaluate the possible differences in the AA/EPA ratio tissue levels between CRC patients with and without synchronous metastases. Moreover, the expression of the most important inflammatory enzymes and mediators, linked with the AA/EPA ratio, have been also assessed. Sixty-eight patients with CRC were enrolled in the study, of which 33 patients with synchronous metastasis. Fatty acid profile analysis in tissue samples was done to examine the levels of AA and EPA. High levels of the AA/EPA ratio were detected in tumor tissue of patients with metastatic CRC. Moreover, an increase of expression of the main enzymes and mediators involved in inflammation was also detected in the same samples. The lipidomic approach of inflammation allows to evaluate lipid homeostasis changes that occur in cancer and in its metastatic process, in order to identify new biomarkers to be introduced into clinical practice.

Background: Adherence to a healthy diet has been reported to be essential for the primary prevention of colorectal cancer, through a reduction of tissue inflammation, a low concentration of circulating lipoproteins and lower levels of serum cholesterol. Since an altered expression of the fatty acids pattern has been demonstrated to be a crucial event in colorectal carcinogenesis, lipidomic analysis is considered able to identify early diagnostic and prognostic biomarkers of complex diseases such as colorectal cancer., Methods: cell membrane fatty acid profile and serum lipoproteins pattern were evaluated by gas chromatography and electrophoresis method respectively., Results: There is a close association between diet and lipidomic profile in colorectal cancer, both in pre-clinical and clinical studies. A modified serum lipoproteins pattern has been demonstrated to be predominant in intestinal tumors., Conclusions: The study of fatty acids profile in cell membrane and the evaluation of serum lipoproteins subfractions could be useful to have an integrate vision on the interactions between lipids and the pathogenesis of colorectal cancer and to understand the mechanisms of action and the consequences of these interactions on human health status.

Cetuximab and panitumumab monoclonal antibodies are a milestone in the history of treatment of metastatic colorectal cancer (mCRC) and point toward future directions for personalized treatment. Recent studies have shown that broader RAS testing is needed to select patients for targeted therapy. The objectives of our study were to identify the prevalence of RAS mutations and evaluate human epidermal growth factor receptor 2 (HER2) expression in KRAS exon 2 wild-type (WT) mCRC patients, correlating the findings with objective response rate, progression-free survival, and overall survival. In total, 29 mCRC patients undergoing treatment with cetuximab therapy were enrolled in this study. By pyrosequencing, mutations were found in 17% of nonresponder patients, in KRAS codon 146 and NRAS codon 12. HER2 positivity was limited to only 1 responder carcinoma specimen. There was no correlation between RAS mutation, HER2/neu expression, and clinicopathologic findings. We highlighted significantly the differences between objective response rate and RAS gene status. The overall survival and progression-free survival of RAS WT patients were higher compared with those with RAS-mutated disease. Clinical response to cetuximab therapy is impaired in the presence of RAS-expanded mutations. In fact, our finding of 5 mutations in RAS-expanded genes allowed us to understand the resistance to cetuximab in 33% of KRAS WT exon 2 nonresponder patients. HER2 does not seem to be a potential biomarker for cetuximab-targeted therapy. These analyses suggest that the assessment of other biomarkers is needed to determine the best treatment for patients with mCRC, to maximize benefit and minimize harm.

Objectives: The influence of age (<70 years and ≥70 years) was retrospectively studied on the quality of life (QoL), incidence of side effects (including skin reactions) and efficacy of chemotherapy plus cetuximab in patients with KRAS wild type (WT) metastatic colorectal cancer (mCRC)., Methods: 225 patients of the Observed study (PS 0-1) were retrieved based on age (< 70 and ≥70 years) and evaluated through EORTC QLQ-C30 and DLQI questionnaires., Results: The two patient groups (141 < 70 and 84 ≥ 70 years, respectively) were balanced with no differences in any of the clinical and pathological characteristics considered. Both groups underwent similar type of first-line chemotherapy plus cetuximab, treatment duration and compliance. Cetuximab therapy caused similar incidence of side effects and impact on QoL in older and younger patients. No difference was observed in progression free survival (PFS) and in disease control rates between the two patient populations. Median overall survival (OS) was higher in patients <70 (27 months, 95% CI: 22.7-31.27) than in patients ≥70 (19 months, 95% CI: 14.65-23.35) (p = 0.002), which is likely due to higher proportions of metastatic resection (27.0% vs 8.3%; p = 0.001) and utilization of second-line therapy in younger group (58.9% vs 42.9%; p = 0.028)., Conclusion: The current data suggest that fit older patients with mCRC can be safely treated with a cetuximab-based therapy, as QoL and safety profile do not seem to be affected by age. In addition, age did not impact the choice of chemotherapy to be associated to cetuximab and treatment compliance., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background/aim: Riboflavin transport in enterocytes is mediated by three translocators: RFVT3 located on the apical membrane, and RFVT1 and RFVT2 on the basolateral membrane. The aim of this study was to investigate whether the expression levels of RFVTs are altered in human colorectal cancer (CRC)., Materials and Methods: In human colon adenocarcinoma cell lines (CaCo2, DLD-1, HT-29) and in tissues of patients with CRC, gene and protein expression levels were evaluated by real time-polymerase chain reaction and western blotting. Intracellular flavin content was determined by high-performance liquid chromatography., Results: RFVT3 and RFVT2 gene and protein expression levels were higher in DLD-1 and HT-29 compared to Caco2 cells. In HT-29 cells, the RFVT1 protein level was drastically lower. These differences are presumably responsible for the higher total flavin content in DLD-1 and HT-29 cells. In tumor tissues of patients with CRC, RFVT1 content was reduced at both protein and mRNA levels compared to normal mucosa. RFVT3 and RFVT2 gene expression levels were increased, while protein expression was reduced, with a small reduction in riboflavin amount., Conclusion: This study provides first evidence that transcription/translation of RFVTs are profoundly altered in CRC., (Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

The early detection of colorectal cancer and determination of its metastatic potential are important factors to set up more efficacious therapeutic strategies. In the present study, we hypothesize that fatty acids analysis in colorectal cancer patients can discriminate between metastatic and non-metastatic patients. Fifty-one consecutive patients with histologically proven colorectal cancer were enrolled in the study and the presence of synchronous metastasis was detected in 25 of these 51 patients. Fatty acid profile analysis in red blood cell membranes was not able to discriminate the metastatic colorectal cancer patients from those without metastasis. However, significant differences in the tumor tissue fatty acid profile were found in metastatic cancer patients when compared to patients without metastasis. Metastatic patients showed significantly lower percentages of Eicosapentaenoic acid (EPA) and higher levels of γ-linolenic acid (GLA), a n -3- and n -6-Polyunsaturated fatty acid (PUFA), respectively. Our findings, suggesting that membrane lipid rearrangement could influence the cellular function and make the cell more prone to metastasis, offer the opportunity to develop nutritional strategies that may be helpful in the prevention and treatment of colorectal cancer., Competing Interests: The authors declare no conflict of interest.

Cetuximab improves efficacy when added to chemotherapy for metastatic colorectal cancer (mCRC). Effective management of skin reactions from cetuximab improves quality of life (QoL), and treatment compliance in clinical trials. No data are available from real-world settings. The ObservEr observational, multicenter, prospective study evaluated QoL, the incidence of skin reactions, and management of chemotherapy plus cetuximab in first-line for mCRC. The primary endpoint was QoL measured with the Dermatology Life Quality Index (DLQI) and EORTC QLQ-C30. Secondary endpoints were the incidence of skin and serious adverse events, median overall and progression-free survival, tumor response, and resection rates. Between May 2011 and November 2012, 228 patients with KRASwt mCRC were enrolled at 28 Italian centers, 225 evaluable, median age 65 years. QoL did not change during treatment and was not affected by the choice of prophylactic or reactive skin management. The incidence of cetuximab-specific grade ≥3 skin reactions was 14%, with no grade 4/5 events. Skin reactions correlated with survival (P = 0.016), and their incidence was influenced by chemotherapy regimen (oxaliplatin vs. irinotecan-Incidence rate ratio [IRR] 1.72, P < 0.0001) and gender (male vs. female-IRR 1.38, P = 0.0008). Compliance at first postbaseline evaluation was 97.75%. Median overall survival was 23.6 months, median progression-free survival 8.3 months. Cetuximab plus chemotherapy did not compromise QoL in the routine clinical setting when patients receive close monitoring plus prophylactic or reactive management of skin reactions. We observed the same correlation between overall survival (OS) and skin reactions reported in controlled clinical trials, also in this setting., (© 2016 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.)

Chemoprevention is the long-term use of different chemical agents, both synthetic and natural, to prevent or delay the onset of disease. Since colorectal cancer has a significant environmental component, it is an ideal disease in which to evaluate the potential benefits of chemopreventive agents. The polyamines, spermine, spermidine and putrescine have been involved in almost all the steps of colorectal tumorigenesis. Consequently, polyamine biosynthesis and catabolism can be considered as promising targets for cancer chemoprevention. A variety of drug formulations have been tested for their efficacy in affecting polyamines in a strategy of colorectal cancer prevention. Different molecules, such as biosynthesis inhibitors and catabolism inducers, have been proposed alone or in combination with other drugs proved to diminish the colorectal cancer risk. Interestingly, also diet can play a role in cancer prevention by affecting polyamines. Several dietary components, such as probiotics or flavonoids, have been shown to affect the polyamine metabolic pathway in colorectal neoplastic tissue. On the other hand, the polyamines ingested with diet might contrast the above cited effects shown by both drugs and nutritional factors. It is, therefore, fundamental to acquire more data also on these aspects in view of an innovative approach to colorectal oncology. This review summarizes data on the role of polyamine metabolism in neoplastic transformation of colorectal mucosa and as possible target for colorectal cancer chemoprevention. Attention will be focused on the influence of drugs and nutritional factors on polyamine metabolism, as well as the role played by dietary polyamines.

Background & Aims: The recent enormous increase in colonoscopy demand prompted this multicentre observational study assessing overall acceptability and efficacy of commonly used bowel preparations in Italian clinical practice., Methods: Consecutive outpatients undergoing colonoscopy were recruited from 9 major gastroenterological centres in Italy. Each patient evaluated overall acceptability of the bowel cleansing preparation through a 0-100mm Visual Analogue Scale. The Visual Analogue Scale score was dichotomized by a median split: 80-100 (high acceptability) vs. 0-79 (low acceptability). Bowel cleansing was assessed through a validated scale. The influence of potential individual determinants on patients' acceptability and cleansing efficacy of the bowel preparations was determined by multivariate analyses., Results: 599 evaluable patients were enrolled; 57.3% received 4L-PEG preparations, 29.5% 2L-PEG preparations and 13.2% 2-glasses-solutions (Na-phosphate/Mg-citrate/Na-picosulphate-containing preparations). Overall acceptability was significantly higher for 2L-PEG and 2-glasses solutions than 4L-PEG (adjusted odds ratio, 4.72; and adjusted odds ratio 2.07, respectively). Successful bowel cleansing achieved with 4L-PEG (85.9%) was similar to 2L-PEG (85.3%; adjusted odds ratio 0.82) and significantly higher than 2-glasses solutions (69.6%; adjusted odds ratio 0.34 vs. 4L-PEG). Split regimen, lower total preparation volume and colonoscopy reason (periodical control vs. 1st procedure) were significantly associated with high acceptability. Age ≥60 years, dissatisfaction with the preparation taken, and ≤4/week bowel movements were major determinants of a poor bowel cleansing., Conclusions: 2L-PEG and 4L-PEG preparations provide the most effective bowel cleansing for colonoscopy in clinical practice, with a significantly higher acceptability for 2L-PEG preparations., (Copyright © 2014 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.)

Background/aim: The study of fatty acid composition of the erythrocytes' membrane can be considered an appropriate biomarker for investigating the relations of the pattern of fatty acids metabolism to a specific disease. The aim of the present study was to analyze the fatty acid profile in red blood cell membranes of patients with colorectal cancer (CRC)., Materials and Methods: Thirteen patients with CRC and 13 patients with no malignant disease were enrolled in the study. Fatty acids were extracted from erythrocytes' membranes and quantified by gas chromatography. The data were analyzed using the Mann-Whitney test., Results: Patients with CRC showed significantly lower mean percentage of n-3 polynunsatured fatty acids (n-3 PUFAs) than controls (5.1% vs. 8.0%, respectively). This finding was reflected in the higher ratio n-6-PUFA/n-3-PUFA observed in cancer patients., Conclusion: Lipidomic analysis of erythrocyte membranes confirmed the presence of an altered fatty acid profile in patients with CRC., (Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)

Chemoresistance is a major obstacle to effective therapy against colorectal cancer (CRC) and may lead to deadly consequences. The metabolism of CRC cells depends highly on the p38 MAPK pathway, whose involvement in maintaining a chemoresistant behavior is currently being investigated. Our previous studies revealed that p38α is the main p38 isoform in CRC cells. Here we show that p38α pharmacological inhibition combined with cisplatin administration decreases colony formation and viability of cancer cells and strongly increases Bax-dependent apoptotic cell death by activating the tumor suppressor protein FoxO3A. Our results indicate that FoxO3A activation up-regulates transcription of its target genes (p21, PTEN, Bim and GADD45), which forces both chemosensitive and chemoresistant CRC cells to undergo apoptosis. Additionally, we found that FoxO3A is required for apoptotic cell death induction, as confirmed by RNA interference experiments. In animal models xenografted with chemoresistant HT29 cells, we further confirmed that the p38-targeted dual therapy strategy produced an increase in apoptosis in cancer tissue leading to tumor regression. Our study uncovers a major role for the p38-FoxO3A axis in chemoresistance, thereby suggesting a new therapeutic approach for CRC treatment; moreover, our results indicate that Bax status may be used as a predictive biomarker., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

In the search for new strategies to efficiently fight colorectal cancer, efforts are being increasingly focused on targeting regulatory signaling pathways involved in cancer-specific features. As a result, several studies have recently addressed the therapeutic potential of molecularly-targeted drugs capable of inhibiting the activity of protein kinases involved in relevant signaling cascades. Here we show that simultaneous inhibition of the DFG-in and DFG-out conformations of p38α by means of type-I and type-II inhibitors is beneficial to impair more efficiently its kinase activity. Moreover, we found that SB202190 (type-I) and sorafenib (type-II) synergize at the molecular and biological level, as co-treatment with these compounds enhances tumor growth inhibition and induction of apoptosis both in colorectal cancer cell lines and animal models. These results support the need to reconsider sorafenib as a therapeutic agent against colorectal cancer and provide new insights that underline the importance to elucidate the activity of protein kinase inhibitors for the treatment of colorectal carcinoma.

Purpose: Fatty acid synthase is a common phenotype to various human cancers including those of prostate, colon, lung, endometrium, and stomach. Increased fatty acid synthase levels have been detected in serum from patients with breast and pancreatic cancer. In this study, serum levels of fatty acid synthase were measured in colorectal cancer patients at different stages of disease., Methods: Consecutive 67 patients with colorectal cancer were enrolled in the study. Serum levels of fatty acid synthase were examined by ELISA test. The Kruskal-Wallis test and the χ (2) method for trend have been used to analyze data., Results: Serum fatty acid synthase levels of patients belonging to three groups of stage disease are statistically different. The patients with stage III and IV have significantly higher serum levels of fatty acid synthase than patients with stage I-II. There is a positive trend in serum fatty acid synthase levels from stage I-II to stage III and IV of disease., Conclusions: Fatty acid synthase levels are associated with the stage of disease in patients with colorectal cancer.

In this review, we summarize recent progress regarding the study of the main enzymes of lipid metabolism involved in colorectal cancer development, namely of a) farnesyltransferase (Ftase), a cytosolic enzyme that catalyzes the first step in the protein farnesylation; b) farnesyl diphosphate synthase (FPPS, which yields FPP, a substrate for Ftase; c) fatty acid synthase (FAS), an enzyme required for the conversion of acetyl-CoA and malonyl-CoA to palmitate; and d) lipoprotein lipase (LPL), the crucial enzyme for intravascular catabolism of triglyceride-rich lipoproteins. Alterations in the levels of these enzymes may contribute to a cell growth advantage acquired during the carcinogenic process and to the development of malignancy. We have demonstrated an elevated Ftase activity in human colorectal cancer (CRC), with differences in Ftase activity related to histological grading, tumor location and KRAS mutation status. Moreover, the first evidence of FPPS activity in human CRC was demonstrated by our study, where a higher FPPS activity and mRNA expression was present in cancer rather than in normal mucosa. We also detected a hyperactivation of FAS in colon cancer, related to tumor location, sex and, p53 mutation status. Our data reinforce the role of lipid metabolism in the regulation of cellular metabolic processes and in carcinogenesis. Moreover, our findings suggest that biological factors including sex, gene mutation status, as well as the stratification of patients with colorectal cancer into right- and left-sided subsets may be important in patient selection for targeted therapies. Our studies in vitro demonstrated that FAS might also be a molecular target for the antiproliferative activity of olive oil polyphenols in a metabolically defined subset of patients with colon cancer. Moreover, we detected that the serum levels of FAS in patients with colorectal cancer are associated with tumor stage. Recently, we found a significant reduction in the levels of FAS and another lipogenic enzyme, LPL, in adipose tissue adjacent to tumor lesions, compared to the levels of FAS detected in paired tissue distant from neoplasia in patients with colorectal cancer. The study of metabolic changes in lipogenic enzyme pathways, as well as the determination of the distribution of individual roles within each biochemical pathway provide a rationale for selecting a particular reaction step suitable for therapeutic intervention.

Lipoprotein lipase (LPL) is the crucial enzyme for intravascular catabolism of triglyceride-rich lipoproteins. Fatty acid synthase (FAS) is a key anabolic enzyme that catalyzes the terminal steps in the novo biosynthesis of 18:2n-6. The involvement of both LPL and FAS in tumor biology has been widely demonstrated in different studies and to verify whether there are regional differences in the expression of these enzymes in visceral adipose tissue from patients with colorectal cancer might be representative of events which sustain tumor growth. The objective of this study was to evaluate LPL and FAS activity and expression of their genes in adipose tissue adjacent to neoplasia and distant from it from patients operated for colorectal cancer. LPL enzymatic activity was evaluated by a fluorescent method and FAS activity by a radiometer assay. Reverse-transcription and real-time PCR were used to detect mRNA levels of two enzymes. Our findings show a significant reduction in both LPL and FAS gene expression and activity levels in adipose tissue adjacent to tumor lesion compared to those detected in paired tissue distant from neoplasia. These results underline the influence of tumor microenvironment on lipid metabolism in adipose tissue, demonstrating a tumor-induced impairment in the formation and lipid storing capacity of adipose tissue in patients with colorectal cancer.

Background: The leptin receptor is involved in modulating leptin activity, acting as a carrier protein. A link between leptin or leptin receptor and cancer development has been proposed and here, the hypothesis that leptin and its receptor might be implicated in colorectal cancer (CRC) progression and invasion was investigated., Patients and Methods: A total of 71 consecutive patients with CRC were enrolled in the study. Serum leptin and leptin receptor levels were evaluated by commercial ELISA kits., Results: The multinomial logistic regression model showed a positive association of leptin and leptin receptor with advanced tumor stages, which was significant for the leptin receptor in stage IV of disease., Conclusion: High circulating levels of leptin receptor occur in patients with advanced stage of colon cancer, suggesting a role for leptin in cancer progression and aggressiveness.

Colorectal cancers are a significant cause of mortality in Western societies. The progression of the disease from normal epithelium to the acquisition of the malignant phenotype is accompanied by several biochemical and genetic alterations. Compelling experimental and epidemiologic evidences indicate that diet and nutrition are key factors in modulating colon cancer onset and progression. Therefore, identifying dietary constituents with antitumor activity and investigating their mechanisms of action may lead to significant advances in the prevention of these neoplasms. Moreover, it seems that the potential protection against colorectal cancers of some nutritional factors could be associated with modifications in cellular proliferation and growth. The naturally occurring polyamines, spermine, spermidine, and putrescine, play a key role in hyperproliferation and cell migration and are involved in almost all steps of colorectal tumorigenesis. Mucosal polyamine levels, as a measurement of dysregulated hyperproliferation, have been demonstrated to be significantly associated with cancer risk and have been considered even a specific marker for neoplastic proliferation. Consequently, polyamine metabolism can be considered an attractive target for cancer chemoprevention and chemotherapy. This review summarizes the findings on the possible mechanisms of action of some nutritional components such as flavonoids, polyphenols, and probiotics in colorectal cancers, focusing attention on polyamine metabolism as a possible target. Acquiring more data on this aspect could represent an innovative and interesting approach for new therapeutic and chemopreventive strategies in the management of patients with colorectal neoplasms.

The EGF receptor (EGFR) has emerged as a rational target for anticancer therapy for the treatment of colorectal cancer (CRC). Positive immunohistochemistry (IHC) staining for EGFR is used as a criterion for patient selection; however, doubt has been cast on the utility of this method. Not only is the response to cetuximab, an anti-EGFR mAb, low in patients expressing EGFRs, but a similar response to cetuximab has also been described in patients who do not express EGFRs. This review aims to evaluate the possible cause of the lack of correlation between the efficacy of cetuximab and EGFR IHC staining in CRC, as well as any modifications in the IHC method necessary to optimize patient selection for cetuximab therapy. In our opinion, the heterogeneous expression of the receptor in the neoplastic population and the inability of the mAbs used to predict the response to cetuximab could be the major cause of the failure of IHC staining as a reliable tool for patient selection. The use of specific mAbs directed against the phosphorylated and mutant form (EGFRvIII) of the EGFR could reinstate IHC as a valid predictor of response to therapy.

Objective: Spontaneous non-enzymatic reaction of protein amino groups with glucose and other reducing sugars, known as glycation or Maillard reaction, has long been considered irreversible and inevitably followed by slow conversion of fructosamines and advanced glycation end products. Instead, recent identification of fructosamine 3 kinase (FN3K) has unveiled that fructosamines can be physiologically repaired, so that the FN3K enzyme could be considered a new form of protein repair., Methods: Thirty-one consecutive patients with colorectal cancer were enrolled in the study. FN3K gene expression was determined using quantitative RT-PCR., Results: The mean level of FN3K gene expression was significantly lower in cancer tissue than in the corresponding normal colorectal mucosa, and FN3K gene was under-expressed most particularly in the tumours located on the left side of the colon., Conclusions: Low mRNA levels of this enzyme in colon cancer tissue with respect to normal surrounding mucosa suggests that neoplastic cells have lost a protective enzymatic system. Reduced FN3K gene expression may be important in the pathogenesis and progression of colorectal cancer., ((c) 2008 S. Karger AG, Basel)

Mismatch repair (MMR) proteins are capable of recognizing and processing not only single base-pair mismatches and insertion-deletion loops that occur during DNA replication, but also adducts in DNA resulting from treatment with cancer chemotherapy agents. MMR deficiency leads to microsatellite instability (MSI) and results in resistance to antimetabolites, alkylating and platinating agents, DNA minor groove binders, and inhibitors of topoisomerases. Therefore, anticancer agents that can be recommended for use in MMR deficient colorectal cancers are those that exert their cytotoxicity regardless of the MMR status. These include some alkylating drugs, brostacillin, gemcytabine, photodynamic therapy, taxanes. An approach that is currently receiving much attention is the use of agents such as 5-azacytidine, an inhibitor of the DNA methyltransferases, in combination with inhibitors of histone de-acetylation, to restore the MMR function. A strong anti-proliferative efficacy with a relatively low direct cytotoxicity, obtainable with oloumicine and roscovitine (selective cyclin-dependent kinases inhibitors) can represent a new expedient for the therapeutic treatment of MMR deficient colorectal cancers. The question of how MMR defects modulate the response to chemotherapeutics deserves further investigation, to enable a more aware choice of cancer treatment.

Immunohistochemical (IHC) assessment of the mismatch repair proteins has been proposed as an alternative strategy to molecular biology for evaluating the unstable phenotype of tumors. With the aim of introducing IHC analysis as a routine diagnostic test, the authors compared the expression of MLH1 and MSH2 proteins with a PCR-based microsatellite assay. The concordance rate between the two methods was 90% after IHC evaluation of two different areas of each tumor. These results show that IHC may be as efficient as PCR in detecting unstable phenotype by using only one surgical or biopsy sample.

Objective: Fatty acid synthase (FAS) is a multienzyme protein required for the conversion of acetyl coenzyme A and malonyl coenzyme A to palpitate. High levels of FAS expression have been found in many human cancers, including breast, prostate and colon. In this study, we evaluated FAS activity levels and the expression of its mRNA in normal colorectal mucosa and cancer tissue from patients operated for colorectal carcinoma. In addition, the hypothesis of a relation between FAS activity and p53 mutation status of patients was tested., Methods: Forty-two patients were enrolled in the study. FAS activity was measured by using a radiometric assay. FAS gene expression was determined using quantitative reverse-transcription polymerase chain reaction and p53 mutations by polymerase chain reaction single-strand conformation polymorphism., Results: FAS activity levels were significantly higher in cancer than in the corresponding normal mucosa. Tumors located on the left side of the colon showed higher levels of FAS activity and tumors from male patients showed higher FAS activity than tumors from females. No difference was detected in mRNA FAS levels according to tumor side and gender. Moreover, lower levels of FAS activity were detected in patients carrying the p53 mutation., Conclusions: This study suggests that biological factors including sex and gene mutation status, as well as stratification of patients with colorectal cancer into right- and left-sided subsets, may be important in patient selection for targeted therapies and for the subsequent assessment of objective therapeutic responses., (Copyright 2006 S. Karger AG, Basel.)

Background: Alterations in the mevalonate pathway may contribute to malignant cell growth. There are differences in the aetiology, clinical behaviour, pathological and genetic features in cancer of the right versus the left colon. Here, 3-hydroxy-3-methylglutatyl coenzyme A (HMG-CoA) reductase, farnesylpyrophosphate (FPP) synthase and farnesyltransferase (Ftase) activities were measured in human colorectal cancer (CRC) and normal mucosa in order to evaluate their role as potential markers of malignancy, also in relation to cancer location., Patients and Methods: HMG-CoA reductase, FPP synthase and Ftase activities were determined in CRC and normal mucosa of 90 patients by radiochemical assay., Results: The enzymatic activities were higher in cancer than in normal mucosa. The tumours located at the left side showed higher HMG-CoA reductase activity, whereas the right side tumours showed higher levels of Ftase and FPP synthase activity., Conclusion: The determination of mevalonate pathway enzymes in relation to CRC location may be clinically relevant in designing anticancer targeted therapies.

We have investigated the presence of oestrogen receptor-related (ERR) mRNA in human colorectal tumour tissues and adjacent normal mucosa by reverse transcriptase and nested-polymerase chain reaction. ERRalpha was found in 100% of the patients and ERRgamma in approximately 30% while ERRbeta was not detected at all. The multiplex PCR analysis showed elevated levels of ERRalpha mRNA in tumour tissue compartment as compared to normal mucosa, whereas ERRgamma mRNA was found in lower levels but in both tissue compartments. In contrast, oestrogen receptor (ERalpha and ERbeta) mRNA levels were shown to be decreased in tumour tissues. A positive correlation was observed between ERalpha and ERbeta and between ERalpha and ERRalpha, respectively, in normal mucosa but not in tumour tissue. ERRalpha expression in tumour tissues significantly increased from TNM stages II to IV, whereas both ERs progressively declined. These findings suggest that ERRalpha, as well as the two ERs, might play a critical role in the progression of the colorectal cancer.

Objective: In this study, the serum lipid profile, including total cholesterol (TC), triglycerides (TG), high-density (HDL-C) and low-density lipoprotein cholesterol (LDL-C), has been investigated in colorectal cancer patients (CRC) with and without synchronous distant metastases. The aim of this study was to verify whether the presence of metastases was associated to serum lipid abnormalities, and whether lipoprotein abnormalities were linked to the nutritional status., Methods: The fasting serum lipid profile was examined in 84 CRC patients using colorimetric methods. To determine the nutritional status, the body mass index (BMI) was calculated and serum albumin was measured., Results: Patients with distant metastases showed significantly higher levels of TC, LDL-C and the LDL-C/HDL-C ratio than patients without metastases (p< 0.05). The presence of metastases was positively associated with TC, LDL-C and the LDL-C/HDL-C ratio, being independent of sex, age and BMI., Conclusions: Elevated serum lipid levels may facilitate the development of distant metastasis in CRC patients., ((c) 2005 S. Karger AG, Basel.)

Objective: Farnesyl diphosphate synthase (FPPs) produces FPP which is considered a branch-point intermediate in the synthesis of sterols and isoprenylated cellular metabolites. In this study we investigated whether detectable FPPs activity was present in human colorectal cancer (CRC), also evaluating in vitro the role of this enzyme in the growth and apoptosis of CRC cells by using Pamidronate (PAM), a FPPs activity inhibitor., Methods: The activity level of FPPs was determined in CRC and the normal surrounding mucosa of 50 patients by radiochemical assay. The FPPs mRNA expression was investigated in 15 of 50 patients by quantitative reverse transcriptase polymerase chain reaction (RT-PCR). K-ras mutation was evaluated using PCR and restriction enzyme analysis. Cell growth and apoptosis, after PAM treatment, in human CRC cell line DLD-1 were measured by MTT test and DNA fragmentation, respectively., Results: FPPs activity was detectable in human CRC. FPPs activity and its mRNA were significantly more abundant in cancer samples than in normal mucosa. In vitro PAM resulted in a significant reduction of cell growth and also gave rise to a marked proapoptotic effect., Conclusions: This study provides the first evidence of the presence of FPPs activity in human CRC. Moreover, FPPs enzyme was found to play a significant role in colon cancer proliferation., (Copyright (c) 2004 S. Karger AG, Basel)

Background: The enzyme farnesyltransferase has emerged as an important target for anti-cancer therapies. Farnesyltransferase inhibitors have been introduced in clinical trials of subjects with colorectal cancer. We investigated Farnesyltransferase activity, beta-subunit Farnesyltransferase protein expression and its mRNA in patients with colorectal cancer and its relationship with clinicopathological features and K-ras mutation., Methods: Farnesyltransferase activity was determined by Farnesyltransferase [3H] SPA enzyme assay. Beta-subunit Farnesyltransferase protein expression was investigated by Western blotting and its mRNA by reverse transcriptase-polymerase chain reaction. K-ras mutation was detected by polymerase chain reaction amplification and restriction enzyme analysis. Multiple linear regression analysis was used to analyse relationships among age, sex, site of tumour, Dukes' stage, histological differentiation, K-ras mutation and Farnesyltransferase activity in normal mucosa and cancer., Results: The levels of Farnesyltransferase activity and beta-subunit Farnesyltransferase protein expression were significantly higher in cancer than in normal mucosa. Moreover, tumours located on the right side, with mucinous histological differentiation and with K-ras mutation showed higher levels of Farnesyltransferase activity., Conclusions: Our findings suggest that Farnesyltransferase activity may be a potential marker of tumourigenicity. The differences in Farnesyltransferase activity in relation to histological grading, tumour location and K-ras mutation described here may constitute a starting point for investigating the causes of this variation within the large bowel.

Recently a possible cross talk about the relationship between p53 and beta-catenin has been suggested by the observation that colorectal cancers accumulating beta-catenin (as a result of APC mutations) also exhibit high frequency p53 mutations. Our aim was to evaluate the pattern of both the proteins and match these with the morphological changes in colorectal carcinogenesis. Immunohistochemical patterns of p53 and beta catenin were studied using the natural carcinogenetic model of malignant colorectal sporadic adenoma in 27 formalin-fixed paraffin-embedded polyps. We found a progressive increase of p53 and beta-catenin staining from normal, to dysplastic, and to cancerous epithelium. We noted, in dysplastic and cancerous epithelium, but not in normal tissue, the translocation of beta-catenin from the cytoplasm to the nucleus, and in dysplastic epithelium, a significant correlation between p53 over expression and beta-catenin patterns. Beta-catenin cytoplasmic accumulation seemed to drive p53 over expression already in the early stages of carcinogenesis, while nuclear beta-catenin translocation appeared to be related to a pattern of invasion of neoplastic cells.

Background: Mismatch repair (MMR) proteins (MSH2 and MLH1) deficiency is responsible for microsatellite instability (MSI) status. We evaluated p53 and beta-catenin expressions in colorectal cancer specimens with known microsatellite status, previously assessed by means of the polymerase chain reaction (PCR). We also analyzed the MMR proteins immunostaining and compared the results with those ascertained by PCR., Materials and Methods: Twenty-five colorectal cancer patients were analyzed for immunohistochemical expression of p53, beta-catenin, MSH2 and MLH1 proteins., Results: The microsatellite status was only significantly correlated with p53 expression and MRR proteins pattern., Conclusion: We demonstrated a significantly higher p53 expression in MSI colorectal specimens. The concordance rate between immunohistochemistry and PCR was so high (80%) that the immunohistochemical technique can be proposed as a method to select MSI patients for improved outcome and response to chemotherapy.