Precancerous lesions in colorectal cancer

Single-cell spatial mapping reveals alteration of cell type composition and tissue microenvironment during early colorectal cancer formation

Colorectal cancer (CRC) is the third leading cause of cancer mortality in the United States. Familial adenomatous polyposis (FAP) is a hereditary syndrome that raises the risk of developing CRC, with total colectomy as the only effective prevention. Even though FAP is rare (0.5% of all CRC cases), this disease model is well suited for studying the early stages of malignant transformation as patients form many polyps reflective of pre-cancer states. In order to spatially profile and analyze the pre-cancer and tumor microenvironment, we have performed single-cell multiplexed imaging for 52 samples: 12 normal mucosa,16 FAP mucosa,18 FAP polyps, 2 FAP adenocarcinoma, and 4 sporadic colorectal cancer (CRCs) using Co-detection by Indexing (CODEX) imaging platform. The data revealed significant changes in cell type composition occurring in early stage polyps and during the malignant transformation of polyps to CRC. We observe a decrease in CD4+/CD8+ T cell ratio and M1/M2 macrophage ratio along the FAP disease continuum. Advanced dysplastic polyps show a higher population of cancer associated fibroblasts (CAFs), which likely alter the pre-cancer microenvironment. Within polyps and CRCs, we observe strong nuclear expression of beta-catenin and higher number neo-angiogenesis events, unlike FAP mucosa and normal colon counterparts. We identify an increase in cancer stem cells (CSCs) within the glandular crypts of the FAP polyps and also detect Tregs, tumor associated macrophages (TAMs) and vascular endothelial cells supporting CSC survival and proliferation. We detect a potential immunosuppressive microenvironment within the tumor 'nest' of FAP adenocarcinoma samples, where tumor cells tend to segregate and remain distant from the invading immune cells. TAMs were found to infiltrate the tumor area, along with angiogenesis and tumor proliferation. CAFs were found to be enriched near the inflammatory region within polyps and CRCs and may have several roles in supporting tumor growth. Neighborhood analyses between adjacent FAP mucosa and FAP polyps show significant differences in spatial location of cells based on functionality. For example, in FAP mucosa, naive CD4+ T cells alone tend to localize near the fibroblast within the stromal compartment. However, in FAP polyp, CD4+T cells colocalize with the macrophages for T cell activation. Our data are expected to serve as a useful resource for understanding the early stages of neogenesis and the pre-cancer microenvironment, which may benefit early detection, therapeutic intervention and future prevention.

Association between Bacteroides fragilis and Fusobacterium nucleatum infection and colorectal cancer in Vietnamese patients

BACKGROUND

Colorectal cancer (CRC) is a significant global health concern, and understanding the role of specific bacterial infections in its development and progression is of increasing interest. This cross-sectional study investigated the associations between Bacteroides fragilis (B. fragilis) and Fusobacterium nucleatum (F. nucleatum) infections and Vietnamese CRC patients.

METHODS

192 patients with either polyps or CRC at varying stages were recruited from May 2017 to December 2020. Real-time PCR assessed infection rates and bacterial loads in CRC tissues.

RESULTS

B. fragilis infection was notably higher in CRC tissues (51.6 %) than polyps (9.4 %), with a fivefold higher relative load. Positive associations were found in stages II and III, indicating a fivefold increase in CRC progression risk. F. nucleatum infection rates were significantly higher in CRC tissues (55.2 %) than in polyps (10.5 %). In stage II, the infection rate exceeded that in adjacent tissues. The relative load of F. nucleatum was higher in stage III than in stages I and II. Positive F. nucleatum patients had a 3.2 times higher risk of CRC progression.

CONCLUSION

These findings suggest associations between loading of F. nucleatum or/and B. fragilis with the advanced stages of CRC.

Microbiota-associated mechanisms in colorectal cancer

Colorectal cancer (CRC) is one of the most common cancers worldwide, ranking third in terms of incidence and second as a cause of cancer-related death. There is growing scientific evidence that the gut microbiota plays a key role in the initiation and development of CRC. Specific bacterial species and complex microbial communities contribute directly to CRC pathogenesis by promoting the neoplastic transformation of intestinal epithelial cells or indirectly through their interaction with the host immune system. As a result, a protumoural and immunosuppressive environment is created conducive to CRC development. On the other hand, certain bacteria in the gut microbiota contribute to protection against CRC. In this chapter, we analysed the relationship of the gut microbiota to CRC and the associations identified with specific bacteria. Microbiota plays a key role in CRC through various mechanisms, such as increased intestinal permeability, inflammation and immune system dysregulation, biofilm formation, genotoxin production, virulence factors and oxidative stress. Exploring the interaction between gut microbiota and tumourigenesis is essential for developing innovative therapeutic approaches in the fight against CRC.

Pharmacodynamic components and mechanisms of ginger (Zingiber officinale) in the prevention and treatment of colorectal cancer

ETHNOPHARMACOLOGICAL RELEVANCE

Ginger is a "medicine-food homology" natural herb and has a longstanding medicinal background in treating intestinal diseases. Its remarkable bioactivities, including anti-inflammatory, antioxidant, immunoregulatory, flora regulatory, intestinal protective, and anticancer properties, make it a promising natural medicine for colorectal cancer (CRC) prevention and treatment.

AIM OF THE REVIEW

The purpose is to review the relevant literature on ginger and pharmacodynamic components for CRC prevention and treatment, summarize the possible mechanisms of ginger from clinical studies and animal and in vitro experiments, to provide theoretical support for the use of ginger preparations in the daily prevention and clinical treatment of CRC.

MATERIALS AND METHODS

Literatures about ginger and CRC were searched from electronic databases, such as PubMed, Web of Science, ScienceDirect, Google Scholar and China National Knowledge Infrastructure (CNKI).

RESULTS

This article summarizes the molecular mechanisms of ginger and its pharmacodynamic components in the prevention and treatment of CRC, including anti-inflammatory, antioxidant, immunoregulatory, flora regulatory, intestinal protective, inhibit CRC cell proliferation, induce CRC cell cycle blockage, promote CRC cell apoptosis, suppress CRC cell invasion and migration, enhance the anticancer effect of chemotherapeutic drugs.

CONCLUSIONS

Ginger has potential for daily prevention and clinical treatment of CRC.

The Burden of Cancer and Pre-cancerous Conditions Among Transgender Individuals in a Large Healthcare Network

The current study aimed to examine the prevalence of and risk factors for cancer and pre-cancerous conditions, comparing transgender and cisgender individuals, using 2012-2023 electronic health record data from a large healthcare system. We identified 2,745 transgender individuals using a previously validated computable phenotype and 54,900 matched cisgender individuals. We calculated the prevalence of cancer and pre-cancer related to human papillomavirus (HPV), human immunodeficiency virus (HIV), tobacco, alcohol, lung, breast, colorectum, and built multivariable logistic models to examine the association between gender identity and the presence of cancer or pre-cancer. Results indicated similar odds of developing cancer across gender identities, but transgender individuals exhibited significantly higher risks for pre-cancerous conditions, including alcohol-related, breast, and colorectal pre-cancers compared to cisgender women, and HPV-related, tobacco-related, alcohol-related, and colorectal pre-cancers compared to cisgender men. These findings underscore the need for tailored interventions and policies addressing cancer health disparities affecting the transgender population.

Diagnostic significance of CD10 marker to differentiate colorectal adenocarcinoma from adenomatous polyp: A pathological correlation

Background

Colorectal cancer could be developed from adenomatous polyp. The study aimed to evaluate the diagnostic significance of stromal and epithelial CD10 (Neprilysin) expression in patients with colorectal adenocarcinoma and adenomatous polyps.

Methods

This cross-sectional study was conducted on 141 patients with colorectal adenocarcinoma and adenomatous polyps referred to Ayatollah Rouhani Hospital from March 2020 to March 2021. Differential diagnoses of colorectal adenocarcinoma and adenomatous polyps were made colonoscopically, and then samples were taken from the lesions. The pathologists confirmed the final diagnosis as colorectal adenocarcinoma, high-grade or low-grade adenomatous polyps. The stromal and epithelial CD10 expression was evaluated by immunohistochemistry. The data was analyzed by SPSS 22 software (p<0.05).

Results

Sixty-five (46.1%) of the cases were low-grade polyps that were included positive (4 cases; 6.20%) and negative (61 cases; 93.80%) CD10 expression (P=0.001), also 76 (53.9%) of them were either high-grade polyps (21 cases) or adenocarcinomas (21 cases). Also, epithelial CD10 expression was significantly higher in the well-differentiated adenocarcinoma (38 cases) group than moderate (13 cases) and poor (4 cases) groups (P =0.001). Moreover, the CD10 expression level in the adenomatous polyps (10 positive cases and 76 negative cases) was correlated with the degree of dysplasia (P = 0.001) and the presence of tumor invasion (8 positive cases and 133 negative cases) (P = 0.001).

Conclusion

The CD10 expression is associated with an increased degree of dysplasia and the presence of tumor invasion in patients with pre-neoplastic lesions and colorectal adenocarcinoma.

National and subnational incidence, mortality and associated factors of colorectal cancer in China: A systematic analysis and modelling study

Background

Due to their known variation by geography and economic development, we aimed to evaluate the incidence and mortality of colorectal cancer (CRC) in China over the past decades and identify factors associated with CRC among the Chinese population to provide targeted information on disease prevention.

Methods

We conducted a systemic review and meta-analysis of epidemiolocal studies on the incidence, mortality, and associated factors of CRC among the Chinese population, extracting and synthesising data from eligible studies retrieved from seven global and Chinese databases. We pooled age-standardised incidence rates (ASIRs) and mortality rates (ASMRs) for each province, subregion, and the whole of China, and applied a joinpoint regression model and annual per cent changes (APCs) to estimate the trends of CRC incidence and mortality. We conducted random-effects meta-analyses to assess the effect estimates of identified associated risk factors.

Results

We included 493 articles; 271 provided data on CRC incidence or mortality, and 222 on associated risk factors. Overall, the ASIR of CRC in China increased from 2.75 to 19.39 (per 100 000 person-years) between 1972 and 2019 with a slowed-down growth rate (APC1 = 5.75, APC2 = 0.42), while the ASMR of CRC decreased from 12.00 to 7.95 (per 100 000 person-years) between 1974 and 2020 with a slight downward trend (APC = -0.89). We analysed 62 risk factors with synthesized data; 16 belonging to the categories of anthropometrics factors, lifestyle factors, dietary factors, personal histories and mental health conditions were graded to be associated with CRC risk among the Chinese population in the meta-analysis limited to the high-quality studies.

Conclusions

We found substantial variation of CRC burden across regions and provinces of China and identified several associated risk factors for CRC, which could help to guide the formulation of targeted disease prevention and control strategies.

Registration

PROSPERO: CRD42022346558.

Nanoparticles Containing Oxaliplatin and the Treatment of Colorectal Cancer

BACKGROUND

Colorectal cancer (CRC) is a highly widespread malignancy and ranks as the second most common cause of cancer-related mortality.

OBJECTIVE

Cancer patients, including those with CRC, who undergo chemotherapy, are often treated with platinum- based anticancer drugs such as oxaliplatin (OXA). Nevertheless, the administration of OXA is associated with a range of gastrointestinal problems, neuropathy, and respiratory tract infections. Hence, it is necessary to devise a potential strategy that can effectively tackle these aforementioned challenges. The use of nanocarriers has shown great potential in cancer treatment due to their ability to minimize side effects, target drugs directly to cancer cells, and improve drug efficacy. Furthermore, numerous studies have been published regarding the therapeutic efficacy of nanoparticles in the management of colorectal cancer.

METHODS

In this review, we present the most relevant nanostructures used for OXA encapsulation in recent years, such as solid lipid nanoparticles, liposomes, polysaccharides, proteins, silica nanoparticles, metal nanoparticles, and synthetic polymer-carriers. Additionally, the paper provides a summary of the disadvantages and limits associated with nanoparticles.

RESULTS

The use of different carriers for the delivery of oxaliplatin increased the efficiency and reduced the side effects of the drug. It has been observed that the majority of research investigations have focused on liposomes and polysaccharides.

CONCLUSION

This potentially auspicious method has the potential to enhance results and enhance the quality of life for cancer patients undergoing chemotherapy. However, additional investigation is required to ascertain the most suitable medium for the transportation of oxaliplatin and to assess its efficacy through clinical trials.

Association between severe hepatic steatosis examined by Fibroscan and the risk of high-risk colorectal neoplasia

The prevalence of colorectal neoplasm in patients with non-alcoholic fatty liver disease has increased twice as high as that in the general population. FibroScan is a new modality for evaluating hepatic steatosis. This study aimed to investigate the relationship between the risk of high-risk colorectal neoplasia and hepatic steatosis examined using FibroScan. This was a cross sectional study of prospectively enrolled subjects who were scheduled to undergo index colonoscopy as a health screening between March 2018 and February 2019. The severity of steatosis was graded as normal, mild, moderate, or severe using FibroScan. A total of 140 consecutive subjects were enrolled and sequentially examined using FibroScan and colonoscopy. Subjects with hepatic steatosis had more high-risk colorectal neoplasia than those without hepatic steatosis. In addition, tumor size was larger in subjects with hepatic steatosis. In multivariable analysis, severe hepatic steatosis was an independent risk factor for high-risk colorectal neoplasia (adjusted odds ratio: 3.309, confidence interval: 1.043-10.498, p = 0.042). Alcohol consumption was also identified as a risk factor for high-risk colorectal neoplasia. In conclusion, severe hepatic steatosis on FibroScan is associated with the development of high-risk colorectal neoplasia. Thus, physicians should be aware of the association between colorectal neoplasia and hepatic steatosis assessed by FibroScan and its clinical implications.

Possible role of nuclear factor erythroid 2-related factor 2 in the progression of human colon precancerous lesions

BACKGROUND

Increased levels of oxidative stress/cell inflammation contribute to colorectal cancer (CRC) onset. Nuclear factor-erythroid 2-related factor 2 (Nrf2) and its controlled growth factor erv1-like (Gfer) gene regulate redox-sensitive and anti-inflammatory mechanisms, respectively, which can contribute to promoting cancer development.

AIM

We evaluated Nrf2 and Gfer RNA expression and Nrf2 protein expression in colon mucosa in order to establish their possible involvement in the early stage of CRC.

METHODS

Forty subjects were enrolled after a histological evaluation of their colon biopsies. They included 20 subjects with a sporadic colorectal adenoma (SpCA group) and 20 without precancerous lesions (controls). Biopsy samples were processed for gene expression analysis and protein expression, using Real-time PCR and immunofluorescence confocal microscopy, respectively.

RESULTS

Nrf2 and Gfer mRNA expression were significantly reduced (p=0.007 and p<0.003, respectively) in SpCA tissues compared to normal mucosa from controls. Furthermore, immunofluorescence analysis confirmed a relevant reduction of Nrf2 in SpCA tissue compared to normal tissue from controls.

CONCLUSIONS

Our data confirm the hypothesis that Nrf2 and Gfer expression may be involved in the initial hits contributing to the multistep process of colon carcinogenesis. Further larger studies are needed to confirm if Nrf2 and Gfer are potential risk/prognostic factors for cancer development.

Developing and validating polygenic risk scores for colorectal cancer risk prediction in East Asians

Several polygenic risk scores (PRSs) have been developed to predict the risk of colorectal cancer (CRC) in European descendants. We used genome-wide association study (GWAS) data from 22 702 cases and 212 486 controls of Asian ancestry to develop PRSs and validated them in two case-control studies (1454 Korean and 1736 Chinese). Eleven PRSs were derived using three approaches: GWAS-identified CRC risk SNPs, CRC risk variants identified through fine-mapping of known risk loci and genome-wide risk prediction algorithms. Logistic regression was used to estimate odds ratios (ORs) and area under the curve (AUC). PRS115-EAS , a PRS with 115 GWAS-reported risk variants derived from East-Asian data, validated significantly better than PRS115-EUR derived from European descendants. In the Korea validation set, OR per SD increase of PRS115-EAS was 1.63 (95% CI = 1.46-1.82; AUC = 0.63), compared with OR of 1.44 (95% CI = 1.29-1.60, AUC = 0.60) for PRS115-EUR . PRS115-EAS/EUR derived using meta-analysis results of both populations slightly improved the AUC to 0.64. Similar but weaker associations were found in the China validation set. Individuals among the highest 5% of PRS115-EAS/EUR have a 2.52-fold elevated CRC risk compared with the medium (41-60th) risk group and have a 12% to 20% risk of developing CRC by age 85. PRSs constructed using results from fine-mapping and genome-wide algorithms did not perform as well as PRS115-EAS and PRS115-EAS/EUR in risk prediction, possibly due to a small sample size. Our results indicate that CRC PRSs are promising in predicting CRC risk in East Asians and highlights the importance of using population-specific data to build CRC risk prediction models.

Serrated polyp detection rate in colonoscopies performed by gastrointestinal fellows

Background:

Clinically significant serrated polyp detection rate (CSSDR) and proximal serrated polyp detection rate (PSDR) have been suggested as the potential quality benchmarks for colonoscopy (CSSDR = 7% and PSDR = 11%) in comparison to the established benchmark adenoma detection rate (ADR). Another emerging milestone is the detection rate of lateral spreading lesions (LSLs).

Objectives:

This study aimed to evaluate CSSDR, PSDR, ADR, and LSL detection rates among gastrointestinal (GI) fellows performing a colonoscopy. A secondary aim was to evaluate patient factors associated with the detection rates of these lesions.

Design and Methods:

A retrospective review of 799 colonoscopy reports was performed. GI fellow details, demographic data, and pathology found on colonoscopy were collected. Multiple logistic regression analysis was performed to identify the factors associated with CSSDR, PSDR, ADR, and LSL detection rates. A p value < 0.05 was considered statistically significant.

Results:

For our patient population, the median age was 58 years; 396 (49.8%) were male and 386 (48.6%) were African American. The 15 GI fellows ranged from first (F1), second (F2), or third (F3) year of training. We found an overall CSSDR of 4.4%, PSDR of 10.5%, ADR of 42.1%, and LSL detection rate of 3.2%. Female gender was associated with CSSDR, while only age was associated with PSDR. GI fellow level of training was associated with LSL detection rate, with the odds of detecting them expected to be four times higher in F2/F3s than F1s.

Conclusion:

Although GI fellows demonstrated an above-recommended ADR and nearly reached target PSDR, they failed to achieve target CSSDR. Future studies investigating a benchmark for LSL detection rate are needed to quantify if GI fellows are detecting these lesions at adequate rates.

Polygenic risk scores: the future of cancer risk prediction, screening, and precision prevention

Genome-wide association studies (GWASs) have shown that the genetic architecture of cancers are highly polygenic and enabled researchers to identify genetic risk loci for cancers. The genetic variants associated with a cancer can be combined into a polygenic risk score (PRS), which captures part of an individual's genetic susceptibility to cancer. Recently, PRSs have been widely used in cancer risk prediction and are shown to be capable of identifying groups of individuals who could benefit from the knowledge of their probabilistic susceptibility to cancer, which leads to an increased interest in understanding the potential utility of PRSs that might further refine the assessment and management of cancer risk. In this context, we provide an overview of the major discoveries from cancer GWASs. We then review the methodologies used for PRS construction, and describe steps for the development and evaluation of risk prediction models that include PRS and/or conventional risk factors. Potential utility of PRSs in cancer risk prediction, screening, and precision prevention are illustrated. Challenges and practical considerations relevant to the implementation of PRSs in health care settings are discussed.

Genomic and functional characterization of a mucosal symbiont involved in early-stage colorectal cancer

Colorectal cancer is a major health concern worldwide. Growing evidence for the role of the gut microbiota in the initiation of CRC has sparked interest in approaches that target these microorganisms. However, little is known about the composition and role of the microbiota associated with precancerous polyps. Here, we found distinct microbial signatures between patients with and without polyps and between polyp subtypes using sequencing and culturing techniques. We found a correlation between Bacteroides fragilis recovered and the level of inflammatory cytokines in the mucosa adjacent to the polyp. Additional analysis revealed that B. fragilis from patients with polyps are bft-negative, activate NF-κB through Toll-like receptor 4, induce a pro-inflammatory response, and are enriched in genes associated with LPS biosynthesis. This study provides fundamental insight into the microbial microenvironment of the pre-neoplastic polyp by highlighting strain-specific genomic and proteomic differences, as well as more broad compositional differences in the microbiome.

Erzhu Jiedu decoction ameliorates liver precancerous lesions in a rat model of liver cancer

Precancerous lesions are the intermediate stage in the development of liver cancer from cirrhosis. Early intervention measures can effectively prevent the occurrence of liver cancer and prolong the lives of patients, resulting in greater economic effects. Erzhu Jiedu decoction (EJD) is a semiempirical formula that is used in the treatment of cirrhosis and liver cancer according to the academic philosophy of "Preventive treatment of disease" and has achieved good curative effects in clinical practice. The purpose of this study was to investigate the effect of EJD on liver precancerous lesions induced by diethylnitrosamine (DEN) in rats. The results showed that EJD improved the general conditions (body weight, ALT, AST, and GGT) and reduced the number of precancerous lesions in the rat model. Notably, the medium dose of EJD (1.05 g/kg) had better treatment effects than the low dose of EJD, and the high dose of EJD did not further improve the liver lesions compared to the medium dose of EJD. Moreover, EJD effectively reduced the DEN-induced GST-Pi, AFP, CK19, c-Myc, and Ki67 protein expression in liver precancerous tissues. Interestingly, EJD significantly reduced YAP and TAZ mRNA expression in the liver precancerous lesions. Collectively, EJD protects against in the initiation of liver cancer and the regulation of c-Myc and Hippo signaling pathways may be the underlying mechanism.

Genome-wide Modeling of Polygenic Risk Score in Colorectal Cancer Risk

Accurate colorectal cancer (CRC) risk prediction models are critical for identifying individuals at low and high risk of developing CRC, as they can then be offered targeted screening and interventions to address their risks of developing disease (if they are in a high-risk group) and avoid unnecessary screening and interventions (if they are in a low-risk group). As it is likely that thousands of genetic variants contribute to CRC risk, it is clinically important to investigate whether these genetic variants can be used jointly for CRC risk prediction. In this paper, we derived and compared different approaches to generating predictive polygenic risk scores (PRS) from genome-wide association studies (GWASs) including 55,105 CRC-affected case subjects and 65,079 control subjects of European ancestry. We built the PRS in three ways, using (1) 140 previously identified and validated CRC loci; (2) SNP selection based on linkage disequilibrium (LD) clumping followed by machine-learning approaches; and (3) LDpred, a Bayesian approach for genome-wide risk prediction. We tested the PRS in an independent cohort of 101,987 individuals with 1,699 CRC-affected case subjects. The discriminatory accuracy, calculated by the age- and sex-adjusted area under the receiver operating characteristics curve (AUC), was highest for the LDpred-derived PRS (AUC = 0.654) including nearly 1.2 M genetic variants (the proportion of causal genetic variants for CRC assumed to be 0.003), whereas the PRS of the 140 known variants identified from GWASs had the lowest AUC (AUC = 0.629). Based on the LDpred-derived PRS, we are able to identify 30% of individuals without a family history as having risk for CRC similar to those with a family history of CRC, whereas the PRS based on known GWAS variants identified only top 10% as having a similar relative risk. About 90% of these individuals have no family history and would have been considered average risk under current screening guidelines, but might benefit from earlier screening. The developed PRS offers a way for risk-stratified CRC screening and other targeted interventions.

Detection of miR-1246, miR-23a and miR-451 in sera of colorectal carcinoma patients: a case-control study in Cairo University hospital

Background

Colorectal cancer (CRC) has high morbidity and mortality rates. Invasive techniques and other laboratory tests with variable sensitivity and specificity are currently used in diagnosis. Micro ribonucleic acids (miRNAs) have bio vital roles in cell proliferation and apoptosis. Dys-regulation of miRNAs is linked to tumour genesis. The objective of this study was to evaluate the specificity and sensitivity of serum non-invasive biomarkers (micro-RNAs), miR-1246, miR-23a, and miR-451in CRC patients.

Methods

Peripheral expression of three miRNAs (miR-1246, miR-23a and miR-451) was investigated in sera of 37 CRC Egyptian patients and 30 healthy controls, using quantitative real-time polymerase chain reaction trying to reach the optimal non-invasive combination of miRNAs.

Results

Serum miR-1246 was up-regulated in sera of CRC patients compared to normal controls (fold change = 3.55; P<0.001) and showed 100% sensitivity and 80% specificity in diagnosis of CRC. Serum miR-451 was significantly down-regulated in CRC patients (fold change = -4.86; p= 0.014), whereas, miR-23a was down-regulated but this was not statistically significant.

Conclusion

Up-regulation of miR-1246 and down-regulation of miR-451 in the sera of primary CRC Egyptian patients were confirmed with high sensitivity and specificity. Large-scale studies on a wider spectrum of miRNAs in Egyptian CRC patients are needed.

Immune battle at the premalignant stage of colorectal cancer: focus on immune cell compositions, functions and cytokine products

It is now widely accepted that most human cancers, including colorectal cancers (CRCs), develop from premalignant lesions through a long-term multistep process. Host immunity is a key determinant that maintains most premalignant lesions in a stable state via immunosurveillance. However, premalignant cells use diverse strategies to escape host immunosurveillance. A switch in the immune function from immunosurveillance to immunosuppression facilitates the progression of premalignant lesions to established CRCs. This review summarizes the recent progress in understanding alterations in the immune landscape, including immune cell compositions, functions and cytokine products, in the premalignant stage of CRC and provides an updated discussion on its translational significance along the colorectal adenoma-carcinoma sequence.

MicroRNAs expression profiling in Egyptian colorectal cancer patients

Egypt has increased incidence and high rate of early onset colorectal cancer (CRC). This study aimed to profile the expression levels of 84 circulating microRNAs (miRNAs) in Egyptian CRC patients and to evaluate the diagnostic accuracy of some selected miRNAs as diagnostic biomarkers for CRC patients. A total of 129 subjects (84 CRC patients and 45 healthy controls) were enrolled in two independent sample sets: the screening set (39 subjects) and the validation set (90 subjects). The expression profiles of 84 miRNAs were studied by miRNA PCR array in the screening set. Then four miRNAs (let-7c, 21, 26a, 146a) were selected to be studied by quantitative real-time PCR in the validation set. The PCR array results revealed significant up regulation of 20 miRNAs and downregulation of two miRNAs in CRC patients compared to the healthy subjects. Moreover, the expression levels of the four selected miRNAs were significantly higher in CRC serum samples than controls. The ROC analysis revealed that miRNAs (let-7c, 21, 26a and 146a) can effectively discriminate between CRC patients and the controls. The combination of the four miRNAs showed AUC of 0.950 (95% CI [0.898-1.002], p = .001). However, the combination of miR-21 and miR-26a showed the best diagnostic accuracy with AUC of 0.953 (95% CI [0.908-0.999], p = .001). The current data suggest that miRNAs (let-7c, 21, 26a, 146a) could play an important role in CRC development and they can be used as diagnostic biomarkers for CRC.

Association between LINC00657 and miR-106a serum expression levels and susceptibility to colorectal cancer, adenomatous polyposis, and ulcerative colitis in Egyptian population

Colorectal cancer (CRC) represented the second cause of mortality among cancer patients. Long noncoding RNAs and microRNAs (miRNAs) serve as noninvasive biomarkers for CRC surveillance and introduce new therapeutic approaches. LINC00657 and miR-106a expression levels play a pivotal role in CRC. This study included 190 Egyptian subjects, and the expression levels of LINC00657 and miR-106a in serum were measured by using quantitative real-time polymerase chain reaction. We found that upregulation of LINC00657 and downregulation of miR-106a are significantly associated with the development of CRC. Also, a positive correlation was detected between their serum levels. In addition, serum LINC00657 can distinguish adenomatous polyposis (AP) patients and/or ulcerative colitis (UC) patients from controls. Also the miRNA-106a expression level discriminates AP but not UC from healthy individuals. Our study cited new diagnostic biomarkers for CRC, AP, and UC among Egyptians in addition to be noninvasive screening tools for CRC in both healthy subjects and those having precancerous lesions. © 2019 IUBMB Life, 71(9):1322-1335, 2019.

Interferon-microRNA signalling drives liver precancerous lesion formation and hepatocarcinogenesis

OBJECTIVE

Precancerous lesion, a well-established histopathologically premalignant tissue with the highest risk for tumourigenesis, develops preferentially from activation of DNA damage checkpoint and persistent inflammation. However, little is known about the mechanisms by which precancerous lesions are initiated and their physiological significance.

DESIGN

Laser capture microdissection was used to acquire matched normal liver, precancerous lesion and tumour tissues. miR-484(-/-), Ifnar1(-/-) and Tgfbr2(△hep) mice were employed to determine the critical role of the interferon (IFN)-microRNA pathway in precancerous lesion formation and tumourigenesis. RNA immunoprecipitation (RIP), pull-down and chromatin immunoprecipitation (ChIP) assays were applied to explore the underlying mechanisms.

RESULTS

miR-484 is highly expressed in over 88% liver samples clinically. DEN-induced precancerous lesions and hepatocellular carcinoma were dramatically impaired in miR-484(-/-) mice. Mechanistically, ectopic expression of miR-484 initiates tumourigenesis and cell malignant transformation through synergistic activation of the transforming growth factor-β/Gli and nuclear factor-κB/type I IFN pathways. Specific acetylation of H3K27 is indispensable for basal IFN-induced continuous transcription of miR-484 and cell transformation. Convincingly, formation of precancerous lesions were significantly attenuated in both Tgfbr2(△hep) and Ifnar1(-/-) mice.

CONCLUSIONS

These findings demonstrate a new protumourigenic axis involving type I IFN-microRNA signalling, providing a potential therapeutic strategy to manipulate or reverse liver precancerous lesions and tumourigenesis.

Apoptosis-Mediated Chemoprevention by Different Ratios of Fish Oil in Experimental Colon Carcinogenesis

Apoptosis plays an important role in prevention of colon cancer. In the present study, different ratios of fish oil and corn oil increased Fas expression in both phases and a decrease in FasL expression only in post initiation phase. Treatment with fish oil activated the intrinsic apoptotic pathway by increasing Bax expression and Cyt c release and decreasing Bcl-2 levels in both phases. This suggests that intrinsic pathway is upregulated by fish oil; however, Fas-FasL activity may be involved in inhibition of reversal of immune surveillance in tumor cells.

Colorectal cancer liver metastasis trends in the kingdom of Saudi Arabia

BACKGROUND/AIM

To elucidate colorectal cancer (CRC) disease patterns, demographics, characteristics, stage at presentation, metastases, and survival rates of patients, particularly those with liver metastases, at our center as the first report from the Kingdom of Saudi Arabia.

PATIENTS AND METHODS

We performed a retrospective, single-center database study based on the histological diagnosis of CRC in patients seen at the King Khalid University Hospital between 2007 and 2011.

RESULTS

427 cases of CRC with a mean age at diagnosis of 55.47 ΁ 12.85 years, out of which 96% were resected. Stage II was predominant at presentation, followed by both stage III and IV, with the remainder being stage I. One hundred patients had distant metastases, of which the liver was the only location in 54 patients. Mean survival was 3.0 years. Overall survival rates for CRC patients with liver metastases who underwent resection were 30% at 2 years and 17% at 5 years, and the mean survival rate was 1.4 years.

CONCLUSIONS

Both the mean survival rate of our CRC patients with resectable liver metastases and the 5-year survival rate of these patients are lower than global averages. This discrepancy is likely due to late diagnoses rather than more aggressive disease.

Expression of the microtubule-associated protein MAP9/ASAP and its partners AURKA and PLK1 in colorectal and breast cancers

BACKGROUND

Colorectal and breast cancers are among the most common cancers worldwide. They result from a conjugated deficiency of gene maintenance and cell cycle control.

OBJECTIVE

We investigate the expression of the microtubule-associated protein MAP9/ASAP and its two partners AURKA and PLK1 in colorectal tumors as well as in ductal breast cancers.

MATERIALS AND METHODS

26 colorectal cancer samples and adjacent normal tissues and 77 ductal breast cancer samples from grade I to grade III were collected. Real-time quantitative PCR was used to analyse the expression of MAP9, AURKA, and PLK1. Results. Expression of MAP9 is downregulated in colorectal cancer compared to normal tissues (P > 10(-3)), whereas those of AURKA and PLK1 are upregulated (P > 10(-4)). In ductal breast cancer, we found a grade-dependent increase of AURKA expression (P > 10(-3)), while the variations of expression of MAP9 and PLK1 are not significant (P > 0.2).

CONCLUSIONS

MAP9 downregulation is associated with colorectal malignancy and could be used as a disease marker and a new drug target, while AURKA and PLK1 are upregulated. In ductal breast cancer, AURKA overexpression is strongly associated with the tumor grade and is therefore of prognostic value for the progression of the disease.

Quantitative diagnosis of colorectal polyps by spectral domain optical coherence tomography

The principal aim of this study is to investigate the scattering coefficient of colorectal polyp tissues using an optical coherence tomography (OCT) technique. It combines the existing scattering coefficient model and spectral domain OCT to achieve method of early diagnosis of colorectal polyp in hospitals. Seventeen patients were studied, and a total of 1456 data points were extracted by curve-fitting the OCT signals into a confocal single-backscattering model. The results show that the mean scattering coefficient value for colorectal polyps is 1.91 mm(-1) (std: ± 0.54 mm(-1)), which is between the values for normal and malignant tissues. In addition, we studied the difference between adenomatous polyps (n = 15) and inflammatory polyps (n = 2) quantitatively and found that the adenomatous tissues had lower scattering coefficients than the inflammatory ones. The quantitative measurements confirmed that OCT can be used in primary diagnosis to compensate for the deficiencies in methods of pathological diagnosis, with a great potential for early diagnosis of tissues.

The effect of the endoscopist on the wait-time for colorectal cancer surgery

OBJECTIVE

The effect of the specialty of physicians who perform endoscopy on preoperative wait-time of colorectal cancer patients was evaluated.

MATERIAL AND METHODS

Data from 86 patients who have been operated with a diagnosis of colorectal cancer from January 2011-February 2013 regarding age, sex, tumor location, colonoscopy date, surgery date, the expertise and institution of the endoscopist were retrospectively examined. The time between colonoscopy and surgery was accepted as the pre-operative wait time (PWT).

RESULTS

Out of 86 patients, 24 (27.9%) colonoscopies were performed by general surgeons (GS), and 62 (72.1%) by gastroenterologists (GE). When patients who underwent colonoscopy in other centers were extracted, the PWT for our center was 20.4±10.8 days. When grouped according to specialties, the PWT of patients who had their colonoscopy performed by GS was significantly shorter than patients who underwent colonoscopy by GE at the same center (p<0.05). Patient's age, sex and location of the tumor had no effect on PWT (p>0.05).

CONCLUSION

The preparation time for surgery in colorectal cancer patients is influenced by the specialty of the physician performing the procedure. In order to standardize this period, a common flow diagram after endoscopy should be established for patients with suspected malignancy.

Follow-up intervals for precancerous colorectal conditions

Colorectal cancer screening is useful not only in detecting colorectal cancer at an early stage, but also in finding people with precancerous conditions. Proper interference in precancerous patients is good for reducing the occurrence of cancer. The precancerous conditions vary from patient to patient, so is the risk of malignant transformation. However, the lack of clear definition and classification for precancerous colorectal conditions in China makes standard treatment and follow-up management of these people difficult. This review summarizes basic definition and classification for precancerous colorectal conditions, clarifies different risks among people, and introduces the latest progress in follow-up intervals worldwide.