[Early-onset Colorectal Cancer]

Early-Onset Colon Cancer: A Narrative Review of Its Pathogenesis, Clinical Presentation, Treatment, and Prognosis

Colon cancer remains a leading cause of cancer-related deaths, and there has been a rise in the incidence of early-onset colon cancer or colon cancer diagnosed before the age of 50 years old. Early-onset colon cancer has several differences in clinical presentation, as well as histopathology, genetic alteration, and molecular profiling. Early-onset colon cancer can be differentiated into familial type that includes hereditary familial syndrome and sporadic type. Demographic variance also exists in both developing and developed countries. Due to the rising incidence of colon cancer diagnosed in younger age, it is imperative to examine the available evidence regarding the mortality rate of early-onset colon cancer. Colon cancer is affected by numerous modifiable and non-modifiable risk factors. Increasing obesity and lifestyle disorders in the younger population, such as smoking, may influence this increasing trend. There are existing guidelines for colon cancer screening in both average-risk and high-risk individuals. This narrative review aims to highlight the pathogenesis of early-onset CRC; its clinical presentation, treatment, prognosis; and how it differs from late-onset CRC.

LNP-miR-155 cy5 Inhibitor Regulates the Copper Transporter via the β-Catenin/TCF4/SLC31A1 Signal for Colorectal Cancer Therapy

Lipid nanoparticle (LNP) delivery systems are widely used in the delivery of small-molecule drugs and nucleic acids. In this study, we prepared LNP-miR-155 by lipid nanomaterial technology and investigated the effects of LNP-miR-155 on β-catenin/transcription factor 4 (TCF4)/solute carrier family 31 member 1/copper transporter 1 (SLC31A1/CTR1) signaling and copper transport in colorectal cancer. For this, we used an LNP-miR-155 cy5 inhibitor and LNP-miR-155 cy5 mimics for the transfection of HT-29/SW480 cells. The transfection efficiency and uptake efficiency were detected by immunofluorescence. Relevant cell assays confirmed that the LNP-miR-155 cy5 inhibitor mediates the regulation of copper transport through the β-catenin/TCF4/SLC31A1 axis. The LNP-miR-155 cy5 inhibitor reduced cell proliferation, migration, and colony formation and promoted cell apoptosis. We also confirmed that miR-155 downregulates HMG box-containing protein 1 (HBP1) and adenomatous polyposis coli (APC) in cells and activates the function of β-catenin/TCF4 signaling. In addition, we found that the copper transporter, SLC31A1, is highly expressed in colorectal cancer cells. Furthermore, we also found that the complex β-catenin/TCF4 promotes the transcription of SLC31A1 by binding to its promoter region, which sustains the transport of copper from the extracellular region to the intracellular region and increases the activities of Cu2+-ATPase and superoxide dismutase (SOD). In summary, the LNP-miR-155 cy5 inhibitor regulates β-catenin/TCF4 by downregulating SLC31A1-mediated copper transport and intracellular copper homeostasis.

Long-term prognosis of curative endoscopic submucosal dissection for early colorectal cancer according to submucosal invasion: a multicenter cohort study

Background

Endoscopic submucosal dissection (ESD) can provide a high en bloc resection rate and has been widely applied as curative treatment for early colorectal cancer (ECC). However, surgical treatment is occasionally required, and reports on the long-term prognosis of ESD are insufficient. This study aimed to investigate the long-term outcomes of ECC removal by ESD, including local recurrence and metastasis.

Methods

This multicenter study was conducted retrospectively on 450 consecutive patients with ECC who were treated with ESD between November 2003 and December 2013. Clinical, pathological, and endoscopic data were collected to determine tumor depth, resection margin, lymphovascular invasion, and recurrence.

Results

The median follow-up period was 53.8 (12–138 months). The en bloc resection rate was 85.3% (384) and in intramucosal cancer being 84.1% and in superficial submucosal invasion (SM1) cancer being 89.8% (p = 0.158). The curative resection rate was 76.0% (n = 342), and there was no statistical difference between the two groups (77.3% vs. 71.4%, p = 0.231). The overall recurrence free survival rate (RFS) was 98.7% (444/450). In patients with curative resection, there was no statistically significant difference in RFS according to invasion depth (intramucosal: 99.3% vs. SM1: 97.1%, p = 0.248).

Conclusions

Patients with curatively resected ECC treated with ESD showed favorable long-term outcomes. Curatively resected SM1 cancer has a RFS similar to that of intramucosal cancer.

Colon Cancer and Obesity: A Narrative Review

Obesity has played a crucial role in the pathogenesis of various cancers, including colorectal cancer (CRC). Obesity has shown to increase the blood levels of insulin, insulin-like growth factor-1 (IGF-1), leptin, resistin, inflammatory cytokines such as interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), monocyte chemoattractant protein-1 (MCP-1) which in turn acts via various signaling pathways to induce colonic cell proliferation and in turn CRC development. It has been shown that estrogen can prevent and cause CRC based on which receptor it acts. Obese patients have relatively low levels of ghrelin and adiponectin that inhibit cell proliferation which further adds to their risk of developing CRC. Obesity can alter the microbial flora of the gut in such a way as to favor carcinogenesis. Weight loss and good physical activity have been related to a reduced incidence of CRC; obese individuals should be screened for CRC and counseled about the importance of weight reduction, diet, and exercise. The best way of screening is using BMI and waist circumference (WC) to calculate the CRC risk in obese people. This study has reviewed the association between obesity and its pathophysiological association with CRC development.

Examination of the effects of microRNA-145-5p and phosphoserine aminotransferase 1 in colon cancer

Previous studies manifested that microRNA-145-5p is pivotal in the development of various cancers. Nevertheless, the potential function of microRNA-145-5p in colorectal cancer remains unclear. This study attempted to investigate the potential role and possible mechanism of microRNA-145-5p in colon cancer. MicroRNA-145-5p and phosphoserine aminotransferase 1 (PSAT1) levels in colon cancer cells were assayed via quantitative reverse transcription polymerase chain reaction (qRT-PCR). Cell proliferation and cell cycle status were assessed using Cell Counting Kit-8, colony formation, and flow cytometry. The target binding relationship of microRNA-145-5p and PSAT1 was identified using bioinformatics analysis and dual-luciferase reporter gene assay. The result of qRT-PCR disclosed that microRNA-145-5p was markedly down-regulated and PSAT1 level was up-regulated in colon cancer cell lines. Besides, enforced microRNA-145-5p level repressed proliferation of colon cancer cells, and cells were arrested in G0-G1 phase. Bioinformatics analysis and dual-luciferase reporter genes confirmed that PSAT1 was a downstream target of microRNA-145-5p. Enforced PSAT1 level remarkably modulated cell cycle and fostered cell proliferation. Furthermore, rescue experiments displayed that microRNA-145-5p restrained cell cycle progression and cell proliferation and forced PSAT1 level could partially reverse this process. Taken together, our findings demonstrated that microRNA-145-5p repressed colon cancer cell cycle progression and cell proliferation via targeting PSAT1. Our findings identified microRNA-145-5p as an essential tumor repressor gene in colon cancer and may provide a novel biomarker for colon cancer.

Clinicopathologic characteristics of early-onset colorectal cancer

Purpose

The aim of this study was to analysis of the clinicopathological characteristics and prognosis of colorectal cancer (CRC) under the age of 50 years.

Methods

Between January 2009 and December 2018, 1,126 primary CRC patients were included from National Health Insurance Service Ilsan Hospital. The patients were divided into group 1 (n=111, ≤50 years) and group 2 (n=1,015, >50 years). The clinicopathologic features and prognostic outcomes were compared. In addition, to analyze whether there were any differences of those characteristics in 3 groups, patients aged under 50 years were divided into their 20s, 30s, and 40s.

Results

Group 1 had a slightly higher distribution in the left colon and rectum, lower T stage I and higher T stage IV rate, and a significantly higher distribution in stage N2 than group 2 (30.6%:16.3%, P<0.001). Poor histological differentiation of tumors was significantly high in group 1 (P=0.003). The 5-year survival rate for those in their 30s (69.2%) and 40s (91.6%) was higher than those in their 20s who died immediately after surgery (P<0.001). The 5-year disease-free survival rate was also confirmed to be meaningful for each age group, with 0% in their 20s, 53.8% in their 30s, 79.2% in their 40s (P<0.001).

Conclusion

Although the age was not an independent prognostic factor for overall survival in this study, the early onset group of CRCs is more advanced at the time of diagnosis and has a more aggressive histologic type.

Growth Factors, PI3K/AKT/mTOR and MAPK Signaling Pathways in Colorectal Cancer Pathogenesis: Where Are We Now?

Colorectal cancer (CRC) is a predominant malignancy worldwide, being the fourth most common cause of mortality and morbidity. The CRC incidence in adolescents, young adults, and adult populations is increasing every year. In the pathogenesis of CRC, various factors are involved including diet, sedentary life, smoking, excessive alcohol consumption, obesity, gut microbiota, diabetes, and genetic mutations. The CRC tumor microenvironment (TME) involves the complex cooperation between tumoral cells with stroma, immune, and endothelial cells. Cytokines and several growth factors (GFs) will sustain CRC cell proliferation, survival, motility, and invasion. Epidermal growth factor receptor (EGFR), Insulin-like growth factor -1 receptor (IGF-1R), and Vascular Endothelial Growth Factor -A (VEGF-A) are overexpressed in various human cancers including CRC. The phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) and all the three major subfamilies of the mitogen-activated protein kinase (MAPK) signaling pathways may be activated by GFs and will further play key roles in CRC development. The main aim of this review is to present the CRC incidence, risk factors, pathogenesis, and the impact of GFs during its development. Moreover, the article describes the relationship between EGF, IGF, VEGF, GFs inhibitors, PI3K/AKT/mTOR-MAPK signaling pathways, and CRC.

Impact of cuff-assisted colonoscopy for adenoma detection: A protocol of systematic review and meta-analysis

BACKGROUND

Previous studies have reported that cuff-assisted colonoscopy (CAC) can be used for detection of adenoma (DA). However, there are inconsistent results regarding the CAC for DA. Thus, this study will systematically explore the impact of CAC for DA.

METHODS

In order to retrieve potential eligible articles, this study will identify the following electronic databases from their inceptions to present: MEDLINE, EMBASE, Cochrane Library, PSYCINFO, Web of Science, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure. All electronic databases will be searched without any language limitation. We will consider case-controlled studies that focused on exploring the impacts of CAC for DA. Two authors will perform study selection, information collection and risk of bias assessment, respectively. Any discrepancies between 2 authors will be resolved through discussion with a third author.

RESULTS

This study will summarize the most recent evidence to assess the impact of CAC for DA.

CONCLUSION

The findings of this study will provide evidence of CAC for DA in clinical practice.

SYSTEMATIC REVIEW REGISTRATION

INPLASY202040042.