The prognostic factors and multiple biomarkers in young patients with colorectal cancer

Symptom Burden and Time from Symptom Onset to Cancer Diagnosis in Patients with Early-Onset Colorectal Cancer: A Multicenter Retrospective Analysis

Background: The incidence of colorectal cancer (CRC) is decreasing in individuals >50 years due to organised screening but has increased for younger individuals. We characterized symptoms and their timing before diagnosis in young individuals. Methods: We identified all patients diagnosed with CRC between 1990-2017 in British Columbia, Canada. Individuals <50 years (n = 2544, EoCRC) and a matched cohort >50 (n = 2570, LoCRC) underwent chart review to identify CRC related symptoms at diagnosis and determine time from symptom onset to diagnosis. Results: Across all stages of CRC, EoCRC presented with significantly more symptoms than LoCRC (Stage 1 mean ± SD: 1.3 ± 0.9 vs. 0.7 ± 0.9, p = 0.0008; Stage 4: 3.3 ± 1.5 vs. 2.3 ± 1.7, p < 0.0001). Greater symptom burden at diagnosis was associated with worse survival in both EoCRC (p < 0.0001) and LoCRC (p < 0.0001). When controlling for cancer stage, both age (HR 0.87, 95% CI 0.8-1.0, p = 0.008) and increasing symptom number were independently associated with worse survival in multivariate models. Conclusions: Patients with EoCRC present with a greater number of symptoms of longer duration than LoCRC; however, time from patient reported symptom onset was not associated with worse outcomes.

Poor prognosis of young male patients with stage III colorectal cancer: A multicenter retrospective study

BACKGROUND AND OBJECTIVES

The number of young patients with colorectal cancer (CRC) is increasing. However, sex-dependent differences in the prognosis of young CRC remain unknown.

METHODS

We investigated patients aged <70 years with stage III CRC treated between January 2000 and December 2010 in 24 Japanese referral hospitals. Patients were divided into subgroups by age of 50 years (early-onset and late-onset groups) and sex, and clinical characteristics and survival outcomes were compared. Risk factors associated with poor survival outcomes were also analyzed.

RESULTS

Among 4758 consecutive patients, 771 (16%) were <50 years. Regardless of sex, there were more patients with rectal cancer and treated with adjuvant chemotherapy in the early-onset group. Among males, tumors in the early-onset group were poorly differentiated (p < 0.001), and patients were diagnosed at an advanced N stage (p = 0.010). Among females, there were more patients with left-sided cancer in the early-onset group (p < 0.001). Relapse-free survival (RFS) and overall survival (OS) were worse in the early-onset group than in the late-onset group (5-year RFS rates: 58% and 63%, p = 0.024; 5-year OS rates: 76% and 81%, p = 0.041, respectively), while there were no age-dependent differences in the survival outcomes of female CRC patients. A multivariate analysis identified age <50 years as one of the independent risk factors associated with poor RFS in male stage III CRC patients (p = 0.032) CONCLUSIONS: Young male patients with stage III CRC showed poorer survival outcomes than their older counterparts. Therefore, age- and sex-related differences in the incidence of CRC recurrence need to be considered.

Wavelet scattering networks in deep learning for discovering protein markers in a cohort of Swedish rectal cancer patients

BACKGROUND

Cancer biomarkers play a pivotal role in the diagnosis, prognosis, and treatment response prediction of the disease. In this study, we analyzed the expression levels of RhoB and DNp73 proteins in rectal cancer, as captured in immunohistochemical images, to predict the 5-year survival time of two patient groups: one with preoperative radiotherapy and one without.

METHODS

The utilization of deep convolutional neural networks in medical research, particularly in clinical cancer studies, has been gaining substantial attention. This success primarily stems from their ability to extract intricate image features that prove invaluable in machine learning. Another innovative method for extracting features at multiple levels is the wavelet-scattering network. Our study combines the strengths of these two convolution-based approaches to robustly extract image features related to protein expression.

RESULTS

The efficacy of our approach was evaluated across various tissue types, including tumor, biopsy, metastasis, and adjacent normal tissue. Statistical assessments demonstrated exceptional performance across a range of metrics, including prediction accuracy, classification accuracy, precision, and the area under the receiver operating characteristic curve.

CONCLUSION

These results underscore the potential of dual convolutional learning to assist clinical researchers in the timely validation and discovery of cancer biomarkers.

Clinico-Pathological Features, Outcomes and Impacts of COVID-19 Pandemic on Patients with Early-Onset Colorectal Cancer: A Single-Institution Experience

BACKGROUND

The rising incidence of colorectal cancer (CRC) among young patients is alarming. We aim to characterize the clinico-pathological features and outcomes of patients with early-onset CRC (EOCRC), as well as the impacts of COVID-19 pandemic.

METHODS

We included all patients with pathologically confirmed diagnoses of CRC at Hospital Universitario La Paz from October 2016 to December 2021. The EOCRC cut-off age was 50 years old.

RESULTS

A total of 1475 patients diagnosed with CRC were included, eighty (5.4%) of whom had EOCRC. Significant differences were found between EOCRC and later-onset patients regarding T, N stage and metastatic presentation at diagnosis; perineural invasion; tumor budding; high-grade tumors; and signet ring cell histology, with all issues having higher prevalence in the early-onset group. More EOCRC patients had the RAS/ BRAF wild type. Chemotherapy was administered more frequently to patients with EOCRC. In the metastatic setting, the EOCRC group presented a significantly longer median OS. Regarding the COVID-19 pandemic, more patients with COVID-19 were diagnosed with metastatic disease (61%) in the year after the lockdown (14 March 2020) than in the pre-pandemic EOCRC group (29%).

CONCLUSIONS

EOCRC is diagnosed at a more advanced stage and with worse survival features in localized patients. More patients with EOCRC were diagnosed with metastatic disease in the year after the COVID-19 pandemic lockdown. The long-term consequences of COVID-19 are yet to be determined.

Log odds of positive lymph nodes show better predictive performance on the prognosis of early-onset colorectal cancer

BACKGROUND

As the incidence of colorectal cancer tends to be younger, early-onset colorectal cancer (EOCRC) has attracted more attention in recent years. We aimed to assess the optimal lymph node staging system among EOCRC patients, and then, establish informative assessment models for prognosis prediction.

METHODS

Data of EOCRC were retrieved from the Surveillance, Epidemiology, and End Results database. Survival prediction ability of three lymph node staging systems including N stage of the tumor node metastasis (TNM) staging system, lymph node ratio (LNR), and log odds of positive lymph nodes (LODDS) was assessed and compared using Akaike information criterion (AIC), Harrell's concordance index (C-index), and likelihood ratio (LR) test. Univariate and multivariate Cox regression analyses were conducted to identify the prognostic predictors for overall survival (OS) and cancer-specific survival (CSS). Effectiveness of the model was demonstrated by receiver operative curve and decision curve analysis.

RESULTS

A total of 17,535 cases were finally included in this study. All three lymph node staging systems showed significant performance in survival prediction (p < 0.001). Comparatively, LODDS presented a better ability of prognosis prediction with lower AIC (OS: 70,510.99; CSS: 60,925.34), higher C-index (OS: 0.6617; CSS: 0.6799), and higher LR test score (OS: 998.65; CSS: 1103.09). Based on independent factors identified from Cox regression analysis, OS and CSS nomograms for EOCRC were established and validated.

CONCLUSIONS

LODDS shows better predictive performance than N stage or LNR among patients with EOCRC. Novel validated nomograms based on LODDS could effectively provide more prognostic information than the TNM staging system.

Influence of Sex and Age on Site of Onset, Morphology, and Site of Metastasis in Colorectal Cancer: A Population-Based Study on Data from Four Italian Cancer Registries

The prognosis of colorectal cancer is affected by factors such as site of origin, tumor morphology, and metastasis at diagnosis, but also age and sex seem to play a role. This study aimed to investigate within the Italian population how sex and age interact in influencing certain aspects of the disease and how they affect patient survival, particularly in the metastatic cohort. Data from four cancer registries were collected, and patients were classified by sex and age (<50, 50-69, and >69 years). Two separate analyses were conducted: one for patients having right or left colon cancer with adenocarcinoma or mucinous morphology, and one for patients having metastases at diagnosis. Women showed significant differences in right colon cases from the youngest to oldest age group (36% vs. 45% vs. 60%). Men <50 years had a significantly higher mucinous carcinoma percentage than their female counterparts (22% vs. 11%), while in the oldest age group women had the highest percentage (15% vs. 11%). The metastatic pattern differed between men and women and by age. The three-year relative survival in the <50 age group was better for women than men, but this survival advantage was reversed in the oldest group. In conclusion, sex and age are factors that influence the biological and clinical characteristics of colorectal cancer, affecting the metastatic pattern as well as patient survival.

The Role of WRAP53 in Cell Homeostasis and Carcinogenesis Onset

The WD repeat containing antisense to TP53 (WRAP53) gene codifies an antisense transcript for tumor protein p53 (TP53), stabilization (WRAP53α), and a functional protein (WRAP53β, WDR79, or TCAB1). The WRAP53β protein functions as a scaffolding protein that is important for telomerase localization, telomere assembly, Cajal body integrity, and DNA double-strand break repair. WRAP53β is one of many proteins known for containing WD40 domains, which are responsible for mediating a variety of cell interactions. Currently, WRAP53 overexpression is considered a biomarker for a diverse subset of cancer types, and in this study, we describe what is known about WRAP53β's multiple interactions in cell protein trafficking, Cajal body formation, and DNA double-strand break repair and its current perspectives as a biomarker for cancer.

Is early-onset cancer an emerging global epidemic? Current evidence and future implications

Over the past several decades, the incidence of early-onset cancers, often defined as cancers diagnosed in adults <50 years of age, in the breast, colorectum, endometrium, oesophagus, extrahepatic bile duct, gallbladder, head and neck, kidney, liver, bone marrow, pancreas, prostate, stomach and thyroid has increased in multiple countries. Increased use of screening programmes has contributed to this phenomenon to a certain extent, although a genuine increase in the incidence of early-onset forms of several cancer types also seems to have emerged. Evidence suggests an aetiological role of risk factor exposures in early life and young adulthood. Since the mid-20th century, substantial multigenerational changes in the exposome have occurred (including changes in diet, lifestyle, obesity, environment and the microbiome, all of which might interact with genomic and/or genetic susceptibilities). However, the effects of individual exposures remain largely unknown. To study early-life exposures and their implications for multiple cancer types will require prospective cohort studies with dedicated biobanking and data collection technologies. Raising awareness among both the public and health-care professionals will also be critical. In this Review, we describe changes in the incidence of early-onset cancers globally and suggest measures that are likely to reduce the burden of cancers and other chronic non-communicable diseases.

East-central Tunisian patients with colorectal adenocarcinoma: a comparative study of the clinicopathological features between patients under 50 years of age and older patients

INTRODUCTION

Colorectal cancer is a major public health problem. In younger patients, its incidence continues to rise and its prognosis appears to be worse. Its treatment is based on curative surgery associated with neo-adjuvant and adjuvant therapies.

AIM

To describe the clinical and pathological characteristics of colorectal cancers in young patients.

METHODS

In this monocentric cohort study, we retrospectively analyzed the clinicopathological features in colorectal cancer patients who underwent treatment from 2002 to 2014. Data of younger (group A, ≤50years) vs older (group B, >50years) patients were compared.

RESULTS

Two hundred and sixty-six patients met inclusion and non-inclusion criteria. The younger and older groups consisted respectively of 25.2% and 74.8% of patients. Both groups were comparable regarding the symptom presentation and duration. Synchronous tumors were more frequent amongst the group A (10.7% vs 1.0%, p = 0.024). Preoperative staging showed a higher frequency of tumors classified as advanced stage (stages III and IV) in the group A (p = 0.001). The patients of group A were diagnosed with a higher proportion of poorly differentiated or undifferentiated adenocarcinomas (13.4% vs 3.5%, p = 0.005), the mucinous character was also more frequent in the group A (28.4%). According to the pTNM (tumor, nodes and metastases) classification, tumors were more advanced in the group A than in group B (80.6% vs 48.7%, p <0.001).

CONCLUSION

This study revealed that colorectal adenocarcinomas in the younger patients, compared to the older ones, were more aggressive with a higher proportion of poorly differentiated or undifferentiated adenocarcinomas, more often mucin production and more advanced tumors.

Survival in Young-Onset Metastatic Colorectal Cancer: Findings From Cancer and Leukemia Group B (Alliance)/SWOG 80405

BACKGROUND

The incidence of young-onset colorectal cancer (yoCRC) is increasing. It is unknown if there are survival differences between young and older patients with metastatic colorectal cancer (mCRC).

METHODS

We studied the association of age with survival in 2326 mCRC patients enrolled in the Cancer and Leukemia Group B and SWOG 80405 trial, a multicenter, randomized trial of first-line chemotherapy plus biologics. The primary and secondary outcomes of this study were overall survival (OS) and progression-free survival (PFS), respectively, which were assessed by Kaplan-Meier method and compared among younger vs older patients with the log-rank test. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated based on Cox proportional hazards modeling, adjusting for known prognostic variables. All statistical tests were 2-sided.

RESULTS

Of 2326 eligible subjects, 514 (22.1%) were younger than age 50 years at study entry (yoCRC cohort). The median age of yoCRC patients was 44.3 vs 62.5 years in patients aged 50 years and older. There was no statistically significant difference in OS between yoCRC vs older-onset patients (median = 27.07 vs 26.12 months; adjusted HR = 0.98, 95% CI = 0.88 to 1.10; P = .78). The median PFS was also similar in yoCRC vs older patients (10.87 vs 10.55 months) with an adjusted hazard ratio of 1.02 (95% CI = 0.92 to 1.13; P = .67). Patients younger than age 35 years had the shortest OS with median OS of 21.95 vs 26.12 months in older-onset patients with an adjusted hazard ratio of 1.08 (95% CI = 0.81 to 1.44; Ptrend = .93).

CONCLUSION

In this large study of mCRC patients, there were no statistically significant differences in survival between patients with yoCRC and CRC patients aged 50 years and older.

Construction of Novel Prognostic Nomogram for Mucinous and Signet Ring Cell Colorectal Cancer Patients with a Survival Longer Than 5 Years

Purpose

Patients and Methods

Results

Conclusion

Early-Onset Colorectal Adenocarcinoma in the IDEA Database: Treatment Adherence, Toxicities, and Outcomes With 3 and 6 Months of Adjuvant Fluoropyrimidine and Oxaliplatin

PURPOSE

Early-onset (EO) colorectal cancer (CRC, age < 50 years) incidence is increasing. Decisions on optimal adjuvant therapy should consider treatment adherence, adverse events, and expected outcomes in a population with life expectancy longer than later-onset (LO) CRC (age ≥ 50 years).

MATERIALS AND METHODS

Individual patient data from six trials in the International Duration Evaluation of Adjuvant Chemotherapy database were analyzed. Characteristics, treatment adherence, and adverse events in stage II or III EO-CRC and LO-CRC were compared. To reduce confounders of non-cancer-related deaths because of age or comorbidities, time to recurrence (3-year relapse-free rate) and cancer-specific survival (5-year cancer-specific mortality rate) were considered.

RESULTS

Out of 16,349 patients, 1,564 (9.6%) had EO-CRC. Compared with LO-CRC, EO-CRC had better performance status (86% v 80%, P < .01), similar T stage (% T1-3/T4: 76/24 v 77/23, P = .97), higher N2 disease rate (24% v 22%, P < .01), more likely to complete the planned treatment duration (83.2% v 78.2%, P < .01), and received a higher treatment dose intensity, especially with 6-month regimens. Gastrointestinal toxicity was more common in EO-CRC; hematologic toxicity was more frequent in LO-CRC. Compared with LO-CRC, significantly worse cancer-specific outcomes were demonstrated especially in high-risk stage III EO-CRC: lower 3-year relapse-free rate (54% v 65%; hazard ratio [HR] 1.33; 95% CI, 1.14 to 1.55; P value < .001) and higher 5-year cancer-specific mortality rate (24% v 20%; HR 1.21; 95% CI, 1.00 to 1.47; P value < .06). In this subgroup, no difference was observed with 3 or 6 months of therapy, with equally poor disease-free survival rates (57% v 56%; HR 0.97; 95% CI, 0.73 to 1.29; P value = .85).

CONCLUSION

Young age is negatively prognostic in high-risk stage III CRC and associated with significantly higher relapse rate; this is despite better treatment adherence and higher administered treatment intensity, suggesting more aggressive disease biology.

Expression Levels of the CA9, WT1, and PRAME Genes and Genotyping-Associated Antigens for the Diagnosis and Prognosis of Colorectal Cancer

Background Colorectal cancer (CRC) is the third most prevalent type of cancer worldwide, and is one of the major health problems in Asia, Africa, Europe, and America. The tumor antigens recently are of interesting indicators as diagnostic and prognostic tools. The aim of the present study is to detect the expression levels of carbonic anhydrase IX (CA9), the Wilms tumor gene (WT1), and the preferentially expressed antigen in melanoma (PRAME) in the peripheral blood of CRC patients in comparison with healthy controls.

Methods A prospective case-control study of CRC patients was conducted. We included 25 newly-diagnosed CRC eligible patients and obtained peripheral blood samples of them as well as 10 blood samples from the control group. All samples were then submitted to deoxyribonucleic acid (DNA) extraction and a molecular study through real-time polymerase chain reaction (PCR).

Results The CRC group consisted of 15 (60%) female and 10 (40%) male patients with a mean age of 50.52 ± 9.8 years, while the control group included 4 (40%) female and 6 (60%) male patients with a mean age of 47.7 ± 7.9 years. The CRC group, 24 (96%) of patient samples were CA9-positive with strong statistically significant differences (p < 0.00001; sensitivity: 96%; specificity: 90%). Regarding the WT1 gene, there were 11 (44%) positive samples in the CRC group, with no statistically significant differences (p = 0.055; sensitivity: 44%; specificity: 90%). The PRAME gene was positive in 9 (36%) samples in the CRC group, with no statistically significant differences (p = 0.357; sensitivity: 36%; specificity: 80%. Among CA9 (24 patients; 96%) of patients with CRC expressed positive results, in WT1 11(91.6%) CRC patients expressed gene, and in PRAME gene, 9 patients with CRC (81.8%) expressed positive results.

Conclusion Overexpression of the CA9 gene in CRC of high sensitivity and specificity to be used as a tool to discriminate CRC from benign associate with high accuracy compare to WT1 and PRAME genes.

The role of PDGFRA as a therapeutic target in young colorectal cancer patients

Background

Young patients with colorectal cancer (CRC) exhibit poor prognoses compared to older patients due to the difficulty in early diagnosis and treatment. However, the underlying molecular characteristics are still unclear.

Methods

We conducted a comprehensive analysis of 49 CRC patients without hereditary CRC using the whole-exome and RNA sequencing with tumor and matched normal samples. A total of 594 TCGA samples and 4 patient-derived cells were utilized for validation.

Results

Consensus molecular subtype 4 (CMS4) (53.85%) and CMS2 (38.46%) were enriched in the young (≤ 40 years) and old (> 60 years) age groups, respectively. A CMS4-associated gene, platelet-derived growth factor receptor α (PDGFRA), was significantly upregulated in young patients with CRC (FC = 3.21, p = 0.0001) and was negatively correlated with age (p = 0.0001, R = − 0.526). Moreover, PDGFRA showed a positive co-expression with metastasis-related genes in young CRC patients. In vitro validation confirmed that young patient-derived cells (PDCs) showed an enriched expression of PDGFRA compared to old PDCs and a reduced proliferation rate by knockdown of PDGFRA. Furthermore, young CRC patients were more sensitive to regorafenib, a PDGFRA-targeting drug, than old CRC patients.

Conclusions

Our study suggests that CRC in young patients is associated with CMS4 and PDGFRA. In addition, PDGFRA may serve potential of novel therapeutic strategies and represent a predictive biomarker of response to regorafenib for young CRC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-03088-7.

Care Patterns and Overall Survival in Patients With Early-Onset Metastatic Colorectal Cancer

PURPOSE

Colorectal cancer (CRC) incidence in patients younger than 50 years of age, commonly defined as early-onset (EO-CRC), is rising. EO-CRC often presents with distinct clinicopathologic features. However, data on prognosis are conflicting and outcomes with modern treatment approaches for metastatic disease are still limited.

MATERIALS AND METHODS

We prospectively enrolled patients with metastatic CRC (mCRC) to a biobanking and clinical data collection protocol from 2014 to 2018. We grouped the cohort based on age at initial diagnosis: < 40 years, 40-49 years, and ≥ 50 years. We used regression models to examine associations among age at initial diagnosis, treatments, clinicopathologic features, and survival.

RESULTS

We identified 466 patients with mCRC (45 [10%] age < 40 years, 109 [23%] age 40-49 years, and 312 [67%] age ≥ 50 years). Patients < 40 years of age were more likely to have received multiple metastatic resections (odds ratio [OR], 3.533; P = .0066) than their older counterparts. Patients with EO-CRC were more likely to receive triplet therapy than patients > 50 years of age (age < 40 years: OR, 6.738; P = .0002; age 40-49 years: OR, 2.949; P = .0166). Patients 40-49 years of age were more likely to have received anti-EGFR therapy (OR, 2.633; P = .0016). Despite differences in care patterns, age did not predict overall survival.

CONCLUSION

Despite patients with EO-CRC receiving more intensive treatments, survival was similar to the older counterpart. However, EO-CRC had clinical and molecular features associated with worse prognoses. Improved biologic understanding is needed to optimize clinical management of EO-CRC. The cost-benefit ratio of exposing patients with EO-CRC to more intensive treatments has to be carefully evaluated.

Clinicopathological patterns and survival outcomes of colorectal cancer among young adults in Malaysia: an institutional cohort study

INTRODUCTION

This study aimed to investigate the clinicopathological patterns and survival outcomes of young-onset colorectal cancer (CRC) in Malaysia.

METHODS

The study consisted of 206 patients with young-onset CRC (age < 50 years at diagnosis) and 1,921 patients with late-onset CRC (age ≥ 50 years at diagnosis) diagnosed during 2002-2016. The clinicopathological characteristics of patients with young-onset CRC were compared with those of patients with late-onset CRC during 2009-2013. Kaplan-Meier survival analysis was performed to determine the overall survival (OS) and disease-specific survival (DSS) in these patients.

RESULTS

The overall proportion of young-onset CRC was 10.7%. Mean age for young-onset CRC was 39.5 ± 7.4 years, with male-to-female ratio of 1.2:1.0. There were more Malay patients with young-onset CRC than late-onset CRC (44.0% vs. 19.9%, p = 0.004). Most CRC were diagnosed at advanced stage in both groups. However, young-onset CRC showed more aggressive tumour characteristics, such as poorer differentiation and mucinous subtype. Despite such differences, OS and DSS in both groups were similar (five-year OS for young-onset CRC vs. late-onset CRC: 44.2% vs. 49.0%, p = 0.40; five-year DSS for young-onset CRC vs. late-onset CRC: 48.8% vs. 57.6%, p = 0.53; mean survival of young-onset CRC vs. late-onset CRC: 4.9 years vs. 5.4 years, p = 0.15). Advanced stage at diagnosis and treatment modality were independent prognostic factors.

CONCLUSION

The unique ethnic and histological differences between patients with young- and late-onset CRC suggest that young-onset CRC may represent a distinct entity. However, despite such differences, prognosis between both groups were equivalent.

Rising incidence of early-onset colorectal cancer - a call to action

The incidence of early-onset colorectal cancer (CRC), which occurs in individuals <50 years of age, has been increasing worldwide and particularly in high-income countries. The reasons for this increase remain unknown but plausible hypotheses include greater exposure to potential risk factors, such as a Western-style diet, obesity, physical inactivity and antibiotic use, especially during the early prenatal to adolescent periods of life. These exposures can not only cause genetic and epigenetic alterations in colorectal epithelial cells but also affect the gut microbiota and host immunity. Early-onset CRCs have differential clinical, pathological and molecular features compared with later-onset CRCs. Certain existing resources can be utilized to elucidate the aetiology of early-onset CRC and inform the development of effective prevention, early detection and therapeutic strategies; however, additional life-course cohort studies spanning childhood and young adulthood, integrated with prospective biospecimen collections, omics biomarker analyses and a molecular pathological epidemiology approach, are needed to better understand and manage this disease entity. In this Perspective, we summarize our current understanding of early-onset CRC and discuss how we should strategize future research to improve its prevention and clinical management.

Emerging trends in colorectal cancer: Dysregulated signaling pathways (Review)

Colorectal cancer (CRC) is the third most frequently detected type of cancer, and the second most common cause of cancer‑related mortality globally. The American Cancer Society predicted that approximately 147,950 individuals would be diagnosed with CRC, out of which 53,200 individuals would succumb to the disease in the USA alone in 2020. CRC‑related mortality ranks third among both males and females in the USA. CRC arises from 3 major pathways: i) The adenoma‑carcinoma sequence; ii) serrated pathway; and iii) the inflammatory pathway. The majority of cases of CRC are sporadic and result from risk factors, such as a sedentary lifestyle, obesity, processed diets, alcohol consumption and smoking. CRC is also a common preventable cancer. With widespread CRC screening, the incidence and mortality from CRC have decreased in developed countries. However, over the past few decades, CRC cases and mortality have been on the rise in young adults (age, <50 years). In addition, CRC cases are increasing in developing countries with a low gross domestic product (GDP) due to lifestyle changes. CRC is an etiologically heterogeneous disease classified by tumor location and alterations in global gene expression. Accumulating genetic and epigenetic perturbations and aberrations over time in tumor suppressor genes, oncogenes and DNA mismatch repair genes could be a precursor to the onset of colorectal cancer. CRC can be divided as sporadic, familial, and inherited depending on the origin of the mutation. Germline mutations in APC and MLH1 have been proven to play an etiological role, resulting in the predisposition of individuals to CRC. Genetic alterations cause the dysregulation of signaling pathways leading to drug resistance, the inhibition of apoptosis and the induction of proliferation, invasion and migration, resulting in CRC development and metastasis. Timely detection and effective precision therapies based on the present knowledge of CRC is essential for successful treatment and patient survival. The present review presents the CRC incidence, risk factors, dysregulated signaling pathways and targeted therapies.

Specificity of the Multi-Target Stool DNA Test for Colorectal Cancer Screening in Average-Risk 45-49 Year-Olds: A Cross-Sectional Study

High-specificity colorectal cancer screening is desirable to triage patients <50 years for colonoscopy; however, most endorsed colorectal cancer screening tests have not been rigorously evaluated in younger populations. This prospective cross-sectional study determined the specificity of the multitarget stool DNA (mt-sDNA) test in an average-risk screening population of 45 to 49 year-olds. Specificity was the primary outcome and was measured in participants without colorectal cancer or advanced precancerous lesions [APL- advanced adenomas (AA), and sessile serrated lesions ≥10 mm], and in the subgroup of participants with negative colonoscopic findings. APL sensitivity was a secondary outcome. The evaluable cohort included those who completed the study without protocol deviations and had a usable mt-sDNA test. Of 983 enrolled participants, 816 formed the evaluable cohort, with a mean age of 47.8 (SD, 1.5) years; 47.7% were women. No participants had colorectal cancer, 49 had APL, 253 had nonadvanced adenomas (NAA), and 514 had negative colonoscopic findings. mt-sDNA test specificity was 95.2% (95% CI, 93.4-96.6) in participants with NAA or negative findings [96.3% (confidence interval (CI), 94.3%-97.8%)] in those with negative findings, and did not differ by sex (P = 0.75) or race (P = 0.36) in participants with NAA or negative findings. Sensitivity for APL was 32.7% (CI, 19.9-47.5%), with most APL (83.7%) measuring 10-19 mm and none having high-grade dysplasia. The area under the ROC curve for discriminating between APL and lesser findings was 0.72 (CI, 0.64-0.81). mt-sDNA's high specificity would help minimize risk from unnecessary diagnostic procedures in this age group. This study shows that mt-sDNA has high specificity among average-risk 45 to 49-year olds, supporting its use as a noninvasive option for colorectal cancer screening. PREVENTION RELEVANCE: This study shows that mt-sDNA has high specificity among average-risk 45-49 year olds, supporting its use as a non-invasive option for colorectal cancer screening.

Differential Expression of PEG10 Contributes to Aggressive Disease in Early Versus Late-Onset Colorectal Cancer

BACKGROUND

Colorectal cancer is a leading cause of cancer-related death. Early onset colorectal cancer (age ≤45 y) is increasing and associated with advanced disease. Although distinct molecular subtypes of colorectal cancer have been characterized, it is unclear whether age-related molecular differences exist.

OBJECTIVE

We sought to identify differences in gene expression between early and late-onset (age ≥65 y) colorectal cancer.

DESIGN

We performed a review of our institution's colorectal cancer registry and identified patients with colorectal cancer with tissue specimens available for analysis. We used the Cancer Genome Atlas to initially identify differences in gene expression between early and late-onset colorectal cancer. In vitro experiments were performed on 2 colorectal cancer cell lines.

SETTINGS

The study was conducted at a tertiary medical center.

PATIENTS

Patients with early onset (n = 28) or late onset (age ≥65 y; n = 38) at time of diagnosis were included.

MAIN OUTCOME MEASURES

The primary outcome was differential gene expression in patients with early versus late-onset colorectal cancer. The secondary outcome was patient mortality.

RESULTS

Seven genes had increased expression in younger patients using The Cancer Genome Atlas. Only PEG10 was sufficiently expressed with quantitative polymerase chain reaction and had increased expression in our early onset group. Multivariable linear regression analysis identified age as a significant independent predictor of increased PEG10 expression. Outcomes data from The Cancer Genome Atlas suggests that PEG10 is associated with poor overall survival. In vitro studies in HCT-116 and HT-29 cell lines showed that PEG10 contributes to cellular proliferation and invasion in colorectal cancer.

LIMITATIONS

Tissue samples were from formalin-fixed, paraffin-embedded sections. Many patients did not have mutational status for review.

CONCLUSIONS

PEG10 is differentially expressed in early onset colorectal cancer and may functionally contribute to tumor cell proliferation and invasion. An increase in PEG10 expression correlates with decreased overall survival. See Video Abstract at http://links.lww.com/DCR/B343. LA EXPRESIÓN DIFERENCIAL DE PEG10 CONTRIBUYE A LA ENFERMEDAD AGRESIVA EN EL CÁNCER COLORRECTAL DE INICIO TEMPRANO VERSUS INICIO TARDÍO: El cáncer colorrectal es una de las principales causas de muerte relacionada con el cáncer. El cáncer colorrectal de inicio temprano (edad ≤45 años) está en aumento y asociado con enfermedad avanzada. Aunque se han caracterizado distintos subtipos moleculares del cáncer colorrectal, no está claro si existen diferencias moleculares relacionadas con la edad.Se buscó identificar diferencias en la expresión génica entre el cáncer colorrectal de inicio temprano y tardío (edad ≥ 65 años).Realizamos una revisión del registro de cáncer colorrectal de nuestra institución e identificamos pacientes con cáncer colorrectal con muestras de tejido disponibles para su análisis. Utilizamos el Atlas del Genoma del Cáncer para identificar inicialmente las diferencias en la expresión génica entre el cáncer colorrectal de inicio temprano y de inicio tardío. Se realizaron experimentos in vitro en dos líneas celulares de cáncer colorrectal.El estudio se realizó en un centro médico de tercer nivel.Se incluyeron pacientes con inicio temprano (n = 28) e inicio tardío (edad ≥65 años, n = 38) al momento del diagnóstico.El resultado primario fue la expresión diferencial de genes en pacientes con cáncer colorrectal de inicio temprano versus tardío. El resultado secundario fue la mortalidad de los pacientes.Siete genes aumentaron su expresión en pacientes más jóvenes usando el Atlas del Genoma del Cáncer. Solo PEG10 se expresó suficientemente con la reacción en cadena de la polimerasa cuantitativa y tuvo una mayor expresión en nuestro grupo de inicio temprano. El análisis de regresión lineal multivariable identificó la edad como un predictor independiente significativo del aumento de la expresión de PEG10. Los datos de resultados de el Atlas del Genoma del Cáncer sugieren que PEG10 está asociado con una pobre supervivencia general. Los estudios in vitro en líneas celulares HCT-116 y HT-29 mostraron que PEG10 contribuye a la proliferación e invasión celular en el cáncer colorrectal.Las muestras de tejido fueron de portaobjetos embebidos en parafina fijados con formalina. Muchos pacientes no tenían el estado de mutación para su revisión.El PEG10 se expresa diferencialmente en el cáncer colorrectal de inicio temprano y puede contribuir funcionalmente a la proliferación e invasión de células tumorales. El aumento en la expresión de PEG10 se correlaciona con la disminución de la supervivencia general. Consulte Video Resumen en http://links.lww.com/DCR/B343.

Driver gene alterations in lung adenocarcinoma: Demographic features of 2544 Chinese cases

BACKGROUND

To understand the association between driver gene variations and age and gender in patients with lung adenocarcinoma, we investigated mutations of the three most important driver genes-epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK) fusion genes and c-ros oncogene 1 (ROS1)-in this retrospective cohort study.

METHODS

Patients newly diagnosed with lung adenocarcinoma who received EGFR and ALK/ROS1 gene tests at our hospital from September 2014 to May 2019 were enrolled. EGFR mutations and ROS1 fusions were examined by ARMS-PCR and ALK fusions by Ventana-D5F3 IHC assay and ARMS-PCR.

RESULTS

Of 2544 eligible subjects, 2539 accomplished EGFR mutation tests. The prevalence of EGFR mutations was 62.1% in females, higher than that of 45.1% in males. In females, the EGFR mutation rate remained relatively stable at 60%-65% across the six age groups. Females showed an increased distribution of EGFR L858R and a decreased distribution of exon 19 deletion (19Del) by age. The incidence of ALK/ROS-1 rearrangements decreased significantly with age.

CONCLUSIONS

EGFR 19Del mutation is more prevalent in younger males and females, while L858R mutation is prevalent in older females. Both ALK and ROS1 rearrangements are more common in younger lung adenocarcinoma. The young lung adenocarcinoma population is a distinct group rich in targetable genomic alterations, and more research is needed to understand the mechanism.

Patients with early-onset rectal cancer aged 40 year or less have similar oncologic outcomes to older patients despite presenting in more advanced stage; A retrospective cohort study

BACKGROUND

Early-onset colon and rectal cancer has increased in alarming rates. The present study reviewed the characteristics and outcome of early-onset rectal cancer in patients aged ≤40 years.

METHODS

This was a retrospective cohort study on rectal cancer patients who were treated in a tertiary center in the Middle East. Baseline characteristics and outcomes of patients ≤40 years were compared with patients >40 years. Main outcome measures were patients' and tumor characteristics, local recurrence, distance metastasis, overall survival (OS), and disease-free survival (DFS).

RESULTS

Among 244 patients with rectal cancer, 81 (33.2%) aged 40 years or less. 56.8% of patients ≤40 years and 49.7% of patients >40 years presented with stage III/IV disease (p = 0.36). Local recurrence and distant metastasis were detected in 10.3% and 13.2% of patients ≤40 years and in 16.9% and 13.9% of patients >40 years (p = 0.29 and 0.88). The 3-year OS and DFS rates of patients ≤40 years were 75% and 80.9% versus 74.2% and 76.5% in patients >40 years (p = 0.9 and 0.59). Patients ≤40 years presented with ulcerative carcinoma (38.3% vs 21.5%, p = 0.01) and signet-ring carcinoma (12.3% vs 2.5%, p = 0.008) more than patients > 40 years.

CONCLUSION

Early-onset rectal cancer accounted for one-third of all patients presenting with rectal cancer. Patients younger than 40 years had higher incidence of mucinous and signet-ring rectal carcinoma, and presented more with advanced stage. The age of patients did not have a significant impact on the oncologic outcome of rectal cancer.

Clinicopathological features and oncological outcomes of patients with young-onset rectal cancer

BACKGROUND

The incidence of rectal cancer among adults aged less than 50 years is rising. Survival data are limited and conflicting, and the oncological benefit of standard neoadjuvant and adjuvant therapies is unclear.

METHODS

Disease-specific outcomes of patients diagnosed with rectal cancer undergoing surgical resection with curative intent between 2006 and 2016 were analysed.

RESULTS

A total of 797 patients with rectal cancer were identified, of whom 685 had surgery with curative intent. Seventy patients were younger than 50 years and 615 were aged 50 years or more. Clinical stage did not differ between the two age groups. Patients aged less than 50 years were more likely to have microsatellite instability (9 versus 1·6 per cent; P = 0·003) and Lynch syndrome (7 versus 0 per cent; P < 0·001). Younger patients were also more likely to receive neoadjuvant chemoradiotherapy (67 versus 53·3 per cent; P = 0·003) and adjuvant chemotherapy (41 versus 24·2 per cent; P = 0·006). Five-year overall survival was better in those under 50 years old (80 versus 72 per cent; P = 0·013). The 5-year disease-free survival rate was 81 per cent in both age groups (P = 0·711). There were no significant differences in the development of locoregional recurrence or distant metastases.

CONCLUSION

Despite accessing more treatment, young patients have disease-specific outcomes comparable to those of their older counterparts.

m6 A RNA methylation regulators contribute to malignant progression in rectal cancer

N6,2'-O-dimethyladenosine (m⁶ A) RNA methylation, which is correlated with cancer initiation and progression, is dynamically regulated by m⁶ A RNA methylation regulators, including writers, erasers, and readers. Two subgroups of rectal cancer, including cluster1 and cluster2, were identified based on consensus clustering to m⁶ A RNA methylation regulators. A protein-protein interaction network was constructed and hub genes were identified. The results demonstrated that the expression of WTAP was significantly associated with YTHDC1 and YTHDF2. The principal component analysis was used to compare the transcriptional profile between cluster1 and cluster2 subgroups. By using two identified m⁶ A RNA methylation regulators, we constructed a risk signature to predict the survival outcomes of rectal cancer. The results revealed that YTHDC2 and YTHDF2 were protective genes with HR < 1. The coefficients obtained from the least absolute shrinkage and selection operator algorithm were used to calculate the risk score. Patients were then divided into low- and high-risk groups based on the median risk score. The survival analysis demonstrated that there were significant differences in overall survival between these two groups (p < .05). The results of the univariate analysis showed that the risk score, AJCC stage, M stage, and age were associated with overall survival. The results of the multivariate Cox regression analysis showed that the risk score and age were still significantly associated with the overall survival (p < .05). To conclude, m⁶ A RNA methylation regulators can be regarded as potentially useful biomarkers for predicting the prognosis and designing a treatment strategy in rectal cancer.

lncRNA KIAA0125 functions as a tumor suppressor modulating growth and metastasis of colorectal cancer via Wnt/β-catenin pathway

Colorectal cancer (CRC) is the third most common cancer in all races worldwide in recent years. The survival of the CRC patients is mostly affected by the stage of the disease at the time of diagnosis. Thus, the current challenge is to find sensitive and reliable biomarkers in early screening of CRC. Recently, emerging evidence has shown that long non-coding RNAs (lncRNAs) may play crucial roles in tumorigenesis. In this study, we found that lncRNA KIAA0125 was downregulated in colorectal tissues and cells. The functional study demonstrated that overexpression of KIAA0125 suppressed cell proliferation, migration, and invasion whereas the reversal effects were seen in silencing experiment. Besides, KIAA0125 inhibited epithelial-mesenchymal transition through Wnt/β-catenin signaling in CRC. Our findings suggested that KIAA0125 may act as an oncosupressor gene and could be considered as a potential diagnosis biomarker in CRC.

Familial and non-familial risk factors associated with incidence of colorectal cancer in young and middle-aged persons in Western Australia

AIMS

The aim of this study was to examine factors including family history, medical history and comorbidities associated with the risk of colorectal cancer (CRC) in young (18-49 years) and middle-age (50-69 years) individuals.

METHODS

State records were used to identify individuals born in Western Australia between 1945 and 1996, and their first-degree relatives. Individuals in the cohort and their relatives were linked to State cancer registry, hospital and mortality data to identify diagnoses of CRC and other risk factors. The associations between CRC and identified risk factors were examined using multivariable logistic regression.

RESULTS

For both young and middle-aged patients, family history of CRC, and a history of smoking, inflammatory bowel disease, liver disease and non-CRC cancer were associated with a significant increase in odds of CRC. In middle-aged patients, having a colonoscopy in the previous 10 years was associated with a reduced odds of CRC regardless of the detection of polyps. However, in young patients only the absence of polyps as confirmed by colonoscopy was associated with a decreased risk of CRC (OR: 0.38, 95%CI: 0.26 - 0.54, p < 0.001).

CONCLUSIONS

Many of the risk factors associated with CRC were similar in young and middle-aged persons, and should be used to identify high risk young patients for screening. The association between colonoscopy and polyps with CRC was modified by age, likely as the result of routine screening in middle-aged patients.

Post-transcriptional Regulation of Colorectal Cancer: A Focus on RNA-Binding Proteins

Colorectal cancer (CRC) is a major health problem with an estimated 1. 8 million new cases worldwide. To date, most CRC studies have focused on DNA-related aberrations, leaving post-transcriptional processes under-studied. However, post-transcriptional alterations have been shown to play a significant part in the maintenance of cancer features. RNA binding proteins (RBPs) are uprising as critical regulators of every cancer hallmark, yet little is known regarding the underlying mechanisms and key downstream oncogenic targets. Currently, more than a thousand RBPs have been discovered in humans and only a few have been implicated in the carcinogenic process and even much less in CRC. Identification of cancer-related RBPs is of great interest to better understand CRC biology and potentially unveil new targets for cancer therapy and prognostic biomarkers. In this work, we reviewed all RBPs which have a role in CRC, including their control by microRNAs, xenograft studies and their clinical implications.

Increased incidence of colon cancer among individuals younger than 50 years: A 17 years analysis from the cancer registry of the municipality of Milan, Italy

BACKGROUND

Colorectal cancer (CRC) overall incidence has been decreasing in the last decade. However, there is evidence of an increasing frequency of early-onset CRC in young individuals in several countries. The aim of this study is to evaluate the trends of CRC occurrence over 17 years in the municipality of Milan, Italy, focusing on early-onset CRC.

POPULATION AND METHODS

This retrospective study was performed using the Cancer Registry of the municipality of Milan, including all cases of CRC diagnosed 1999-2015. Incidence rates were stratified by age and anatomic subsite, and trends over time were measured using the estimated annual percentage change. Age-period-cohort modelling was used to disentangle the different effects.

RESULTS

18,783 cases of CRC were included. CRC incidence rates among individuals aged 50-60 years declined annually by 3% both in colon and in rectal cancer. Conversely, in adults younger than 50 years, overall CRC occurrence increased annually by 0.7%, with a diverging trend for colon (+2.6%) and rectal (-5.3%) cancer. Among individuals aged 60 years and older, CRC incidence rates increased by 1.0% annually up to 2007, and decrease thereafter by 4% per year, both for colon and rectal cancer. Age-period-cohort models showed a reduction of CRC risk for the cohorts born up to 1979, followed by an increase in younger cohorts. In contrast, rectal cancer among women showed a systematic risk decrease for all birth cohorts.

CONCLUSIONS

The study highlights increasing incidence of colon cancer in younger subjects and a decrease in incidence rates for rectal cancer in females.

Genomic alterations and survival in young patients aged under 40 years with completely resected non-small cell lung cancer

Background

Young patients are rarely diagnosed with non-small cell lung cancer (NSCLC), and little is known about its predisposing genomic alterations and survival.

Methods

This retrospective study was conducted to evaluate the genomic alterations, treatment and prognosis of young patients under 40 years old from a cohort of 640 lung adenocarcinoma and squamous carcinoma cases from Zhejiang Cancer Hospital. All patients were examined for EGFR, KRAS, NRAS, PIK3CA, BRAF and HER2 mutations and ALK, ROS1 and RET fusion genes.

Results

In total, 54 patients were aged under 40 years. The frequencies of genomic alterations in younger (≤40 years) and older (>40 years) patients were 68.5% and 54.8%, respectively (P=0.05). Younger patients harbored a higher frequency of fusion genes (22.2% vs. 4.1%, P<0.001) but not gene mutations (46.3% vs. 45.6%, P=0.92). There was a general trend toward shorter recurrence-free survival (RFS) (35.2 vs. 43.8 months, P=0.050), while no overall survival (OS) difference existed between younger and older patients (50.2 vs. 51.4 months, P=0.112).

Conclusions

Younger patients with NSCLC had a higher frequency of gene fusions than older patients and had a trend of worse OS.

Potential Applications of DNA, RNA and Protein Biomarkers in Diagnosis, Therapy and Prognosis for Colorectal Cancer: A Study from Databases to AI-Assisted Verification

In order to find out the most valuable biomarkers and pathways for diagnosis, therapy and prognosis in colorectal cancer (CRC) we have collected the published CRC biomarkers and established a CRC biomarker database (CBD: http://sysbio.suda.edu.cn/CBD/index.html). In this study, we analysed the single and multiple DNA, RNA and protein biomarkers as well as their positions in cancer related pathways and protein-protein interaction (PPI) networks to describe their potential applications in diagnosis, therapy and prognosis. CRC biomarkers were collected from the CBD. The RNA and protein biomarkers were matched to their corresponding DNAs by the miRDB database and the PubMed Gene database, respectively. The PPI networks were used to investigate the relationships between protein biomarkers and further detect the multiple biomarkers. The Kyoto Encyclopaedia of Genes and Genomes (KEGG) pathway enrichment analysis and Gene Ontology (GO) annotation were used to analyse biological functions of the biomarkers. AI classification techniques were utilized to further verify the significances of the multiple biomarkers in diagnosis and prognosis for CRC. We showed that a large number of the DNA, RNA and protein biomarkers were associated with the diagnosis, therapy and prognosis in various degrees in the CRC biomarker networks. The CRC biomarkers were closely related to the CRC initiation and progression. Moreover, the biomarkers played critical roles in cellular proliferation, apoptosis and angiogenesis and they were involved in Ras, p53 and PI3K pathways. There were overlaps among the DNA, RNA and protein biomarkers. AI classification verifications showed that the combined multiple protein biomarkers played important roles to accurate early diagnosis and predict outcome for CRC. There were several single and multiple CRC protein biomarkers which were associated with diagnosis, therapy and prognosis in CRC. Further, AI-assisted analysis revealed that multiple biomarkers had potential applications for diagnosis and prognosis in CRC.

Biomarkers for Stratification in Colorectal Cancer: MicroRNAs

Colorectal cancer (CRC) is one of the most widely recognized and deadly malignancies worldwide. In spite of the fact that the death rates have declined over the previous decade, particularly because of enhanced screening or potential treatment alternatives, CRC still remains the third leading cause of cancer-related mortality in the world, with an estimated incidence of over 1 million new cases and approximately 600 000 deaths estimated yearly. Unlike prostate and lung cancer, CRC is not easily detectable in its early stage, which may also account for its high mortality rate. MicroRNAs (miRNAs) are a class of noncoding RNAs. The roles of these noncoding RNAs have been implicated in cancer pathogenesis, most especially CRC, due to their ability to posttranscriptionally regulate the expression of oncogenes and tumor suppressor genes. Dysregulated expression of many miRNAs regulates the expression of hundreds of growth regulatory genes and pathways that are important in the multistep model of colorectal carcinogenesis. If CRC is detected early, it is a largely treatable disease. Early diagnosis, including the identification of premalignant adenomas, is regarded a major concept for improving patient survival in CRC treatment. Several lines of research suggest that miRNAs are closely implicated in the metastatic process in CRC and some of these miRNAs could be useful as promising clinical tools for identifying specific stages of CRC due to their differential expression. This review discusses the correlation between CRC staging relative to the specific expression of miRNA for early detection, treatment, and disease management.

Early-onset colorectal cancer in young individuals

Treatment of young adults with colorectal cancer (CRC) represents an unmet clinical need, especially as diagnosis in this population might lead to the greatest loss of years of life. Since 1994, CRC incidence in individuals younger than 50 years has been increasing by 2% per year. The surge in CRC incidence in young adults is particularly alarming as the overall CRC frequency has been decreasing. Early-onset CRC are characterized by a more advanced stage at diagnosis, poorer cell differentiation, higher prevalence of signet ring cell histology, and left colon-sided location of the primary tumor. Among EO-CRC, approximately 30% of patients are affected by tumors harboring mutations causing hereditary cancer predisposing syndromes, and 20% have familial CRC. Most notably, the remaining 50% of EO-CRC patients have neither hereditary syndromes nor familial CRC, thus representing a formidable challenge for research. In this review article we summarize epidemiology, clinical and molecular features, heredity and outcome of treatments of EO-CRC, and provide considerations for future perspectives.

A network approach to quantifying radiotherapy effect on cancer: Radiosensitive gene group centrality

Radiotherapy plays a vital role in cancer treatment, for which accurate prognosis is important for guiding sequential treatment and improving the curative effect for patients. An issue of great significance in radiotherapy is to assess tumor radiosensitivity for devising the optimal treatment strategy. Previous studies focused on gene expression in cells closely associated with radiosensitivity, but factors such as the response of a cancer patient to irradiation and the patient survival time are largely ignored. For clinical cancer treatment, a specific pre-treatment indicator taking into account cancer cell type and patient radiosensitivity is of great value but it has been missing. Here, we propose an effective indicator for radiosensitivity: radiosensitive gene group centrality (RSGGC), which characterizes the importance of the group of genes that are radiosensitive in the whole gene correlation network. We demonstrate, using both clinical patient data and experimental cancer cell lines, which RSGGC can provide a quantitative estimate of the effect of radiotherapy, with factors such as the patient survival time and the survived fraction of cancer cell lines under radiotherapy fully taken into account. Our main finding is that, for patients with a higher RSGGC score before radiotherapy, cancer treatment tends to be more effective. The RSGGC can have significant applications in clinical prognosis, serving as a key measure to classifying radiosensitive and radioresistant patients.

Oncogenic Activity of Wrap53 in Human Colorectal Cancer In Vitro and in Nude Mouse Xenografts

Background

WD40-encoding RNA antisense to p53 (Wrap53) has been implicated in cancer development. However, the role of Wrap53 remains unknown in colorectal cancer. The aim of this study was to elucidate the function of Wrap53 in colorectal cancer tumorigenesis and development.

Material/Methods

This study analyzed Wrap53 expression in colorectal cancer tissue specimens using The Cancer Genome Atlas data and tumor cell lines and assessed the effects of Wrap53 knockdown on regulation of cancer cell malignant phenotypes in vitro and in nude mouse xenografts.

Results

Wrap53 expression was upregulated in colorectal cancer tissue specimens and cell lines. Knockdown of Wrap53 expression induced colorectal cancer cell line apoptosis and cell cycle arrest in the G1 phase, but reduced tumor cell line proliferation and invasion in vitro. Knockdown of Wrap53 in a nude mouse xenograft assay inhibited tumor cell line xenograft formation and growth.

Conclusions

Wrap53 is likely a potential oncogene or possesses oncogenic activity in colorectal cancer, promoting colorectal tumorigenesis. Targeting Wrap53 expression may represent a novel strategy for the control of colorectal cancer.

Alcohol consumption promotes colorectal carcinoma metastasis via a CCL5-induced and AMPK-pathway-mediated activation of autophagy

There is a definite relationship between alcohol consumption and colorectal cancer (CRC) development. We investigated effect of alcohol consumption on CRC patients’ progression and prognosis by utilizing epidemiological data and found patients with alcohol consumption increased risks of tumor-node-metastasis (TNM), organ metastasis and poorer prognosis. Because their tumor tissues displayed increased expression of C-C chemokine ligand 5 (CCL5), we hypothesized CCL5 might participate in cancer progression in such patients. Ethanol increased the secretion of CCL5 in two CRC cell lines, HT29 and DLD-1. Treatment with CCL5 directly increased migratory ability of these cells, whereas neutralization or knockdown of CCL5 can partially block alcohol-stimulated migration. We further investigated underlying mechanism of CCL5-induced migration. Our results indicated that effects of CCL5 on migration are mediated by the ability of CCL5 to induce autophagy, a cellular process known to be critical for migration. Using high-throughput sequencing and western blotting, we found induction of autophagy by CCL5 takes place via AMPK pathway. Aforementioned ethanol increases CCL5 secretion, CCL5 activates autophagy through AMPK pathway, and autophagy increases migration was confirmed by experiments with autophagy or AMPK inhibitors. To sum up, our study demonstrates that chronic alcohol consumption may promote metastasis of CRC through CCL5-induced autophagy.

Reconsideration of the optimal minimum lymph node count for young colon cancer patients: a population-based study

BACKGROUND

Currently, young colon cancer (CC) patients continue to increase and represent a heterogeneous patient group. The aim of this study was to explore the optimal minimum lymph node count after CC resection for young patients.

METHODS

We performed a comprehensive search of the Surveillance, Epidemiology, and End Results (SEER) database, 2360 CC patients aged from 20 to 40 were analyzed. X-tile was used to determine the optimal cut-off point of lymph node based on survival outcomes of young patients. The cancer specific survival (CSS) was estimated with Kaplan-Meier method, the Cox proportional hazards regression model was used to analyse independent prognostic factors and exact 95% confidence intervals (CIs).

RESULTS

Using X-tile analysis, 22-node measure was identified as the optimal choice for CC patients aged < 40. The 5-year CSS were 85.8% and 80.9% for patients examining ≥22 nodes and < 22 nodes. Furthermore, we identified that examining < 22 nodes was an independent adverse prognostic factor in patients aged < 40. In addition, the revised 22-node measure could examine more positive nodes than the standard 12-node measure in young patients.

CONCLUSIONS

For young colon cancer patients, the lymph node examination should be differently evaluated. We suggest that 22-node measure may be more suitable for CC patients aged < 40.

TRIAL REGISTRATION

Retrospectively registered.

The impact of young age on the prognosis for colorectal cancer: a population-based study in Taiwan

Background

The impact of age as a prognostic factor for patients with colorectal cancer (CRC) remains controversial, possibly due to heterogeneity between studies in terms of patient numbers, percentage of patients undergoing curative resection, percentage of patients receiving neoadjuvant therapy, or failure to adjust for potential confounding factors. This study used colorectal cancer survival data from the Taiwan Cancer Registry database in order to comprehensively analyze age as a prognostic factor.

Methods

Survival data were analyzed for 62 060 CRC patients diagnosed with adenocarcinoma, mucinous adenocarcinoma, or signet-ring cell carcinoma of the colon and rectum between 1998 and 2005. The rates of all-cause mortality and CRC-related mortality were determined using Kaplan-Meier analysis, and the log-rank test was used to compare differences in survival between different age groups. The crude and adjusted hazard ratios for all-cause and CRC-related mortalities were calculated according to the estimates from the univariable and multivariable Cox proportional hazard models.

Results

Patients in the ≤40 and the 41-50 age groups had a higher proportion of mucinous adenocarcinoma (P < 0.001) and signet-ring cell carcinoma (P < 0.001) compared to the older age groups. After adjusting for gender, histology, and tumor site, patients in the ≤40 age group had a poorer overall survival (OS) and cancer-specific survival compared to patients in the 41-50 and 51-60, and 61-70 age groups (P < 0.001), but a better OS and cancer-specific survival compared to patients in the 71-80 and >80 age groups (P < 0.001).

Conclusions

Our study indicated that age is an important consideration while determining the clinical management of CRC patients.

Colorectal cancer in patients under the age of 40 years: experience from a tertiary care centre in the Czech Republic

INTRODUCTION

Colorectal cancer (CRC) in young patients is not an uncommon disease. Reports on its behaviour in young patients are conflicting. The aim of this study was to investigate patient and tumour characteristics, treatment and prognosis of this disease.

METHODS

Our study group comprised all patients under the age of 40 years treated with CRC at the Department of Surgery at Motol University Hospital in Prague between the years 2005 and 2015.

RESULTS

Thirty-eight patients under 40 years of age diagnosed with CRC were included in the study. Five patients had Lynch syndrome and six had first-degree relatives with CRC. There were 22 rectal tumours. All but four patients underwent resection of the primary tumour, all patients received chemotherapy and 13 patients received biological therapy. Disease recurrence occurred in 25.8%. Five-year survival was 47.9%. Advanced disease and adverse histological subtypes were identified as poor prognostic factors.

CONCLUSIONS

Colorectal cancer in young patients has a high incidence of predisposing conditions, aggressive histological features and advanced disease. Young patients are of a good state of health and thus should receive aggressive therapy. Clinicians should pay more attention to symptoms of CRC in young patients to be able to initiate early treatment.

Chemotherapy Use and Survival Among Young and Middle-Aged Patients With Colon Cancer

Importance

Treatment options for patients with young-onset colon cancer remain to be defined and their effects on prognosis are unclear.

Objective

To investigate receipt of adjuvant chemotherapy by age category (18-49, 50-64, and 65-75 years) and assess whether age differences in chemotherapy matched survival gains among patients diagnosed as having colon cancer in an equal-access health care system.

Design, Setting, and Participants

This cohort study was based on linked and consolidated data from the US Department of Defense's Central Cancer Registry and Military Heath System medical claims databases. There were 3143 patients aged 18 to 75 years with histologically confirmed primary colon adenocarcinoma diagnosed between 1998 and 2007. This study was conducted from December 2015 to August 2016.

Exposures

Patients who underwent surgery and postoperative systemic chemotherapy.

Main Outcomes and Measures

The primary outcome measure of the study was overall survival of patients who only received surgery and those who received both surgery and postoperative systemic chemotherapy.

Results

Of the 3143 patients, 1841 were men (58.6%). Young (18-49 years) and middle-aged (50-64 years) patients were 2 to 8 times more likely to receive postoperative systemic chemotherapy compared with older patients (65-75 years) across all tumor stages. Middle-aged patients with stage I (odds ratio, 5.04; 95% CI, 2.30-11.05) and stage II (odds ratio, 2.42; 95% CI, 1.58-3.72) disease were more likely to receive postoperative chemotherapy compared with older patients. Both groups were more likely to receive multiagent chemotherapy than were older patients (patients aged 18-49 years: odds ratio, 2.48; 95% CI, 1.42-4.32 and patients aged 50-64 years: odds ratio, 2.66; 95% CI, 1.70-4.18). Among patients who received surgery and postoperative systemic chemotherapy, no significant differences were observed in survival among age groups (the 95% CIs of hazard ratios included 1 for young and middle-aged patients compared with older patients for all tumor stages).

Conclusions and Relevance

In an equal-access health care system, we found potential overuse of chemotherapy among young and middle-aged adults with colon cancer. The addition of postoperative systemic chemotherapy did not result in matched survival improvement.

Population-based study of effectiveness of neoadjuvant radiotherapy on survival in US rectal cancer patients according to age

Recent cancer researches pay more attention to younger patients due to the variable treatment response among different age groups. Here we investigated the effectiveness of neoadjuvant radiation on the survival of younger and older patients in stage II/III rectal cancer. Data was obtained from Surveillance, Epidemiology, and End Results (SEER) database (n = 12801). Propensity score matching was used to balance baseline covariates according to the status of neoadjuvant radiation. Our results showed that neoadjuvant radiation had better survival benefit (Log-rank P = 3.25e-06) and improved cancer-specific 3-year (87.6%; 95% CI: 86.4–88.7% vs. 84.1%; 95% CI: 82.8–85.3%) and 5-year survival rates (78.1%; 95% CI: 76.2–80.1% vs. 77%; 95% CI: 75.3–78.8%). In older groups (>50), neoadjuvant radiation was associated with survival benefits in stage II (HR: 0.741; 95% CI: 0.599–0.916; P = 5.80e-3) and stage III (HR: 0.656; 95% CI 0.564–0.764; P = 5.26e-08). Interestingly, neoadjuvant radiation did not increase survival rate in younger patients (< = 50) both in stage II (HR: 2.014; 95% CI: 0.9032–4.490; P = 0.087) and stage III (HR: 1.168; 95% CI: 0.829–1.646; P = 0.372). Additionally, neoadjuvant radiation significantly decreased the cancer-specific mortality in older patients, but increased mortality in younger patients. Our results provided new insights on the neoadjuvant radiation in rectal cancer, especially for the younger patients.

Clinical, cellular, and bioinformatic analyses reveal involvement of WRAP53 overexpression in carcinogenesis of lung adenocarcinoma

Lung cancer, of which non-small cell lung cancer accounts for 80%, remains a leading cause of cancer-related mortality and morbidity worldwide. Our study revealed that the expression of WD repeat containing antisense to P53 (WRAP53) is higher in lung-adenocarcinoma specimens than in specimens from adjacent non-tumor tissues. The prevalence of WRAP53 overexpression was significantly higher in patients with tumor larger than 3.0 cm than in patients with tumor smaller than 3.0 cm. The depletion of WRAP53 inhibits the proliferation of lung-adenocarcinoma A549 and SPC-A-1 cells via G1/S cell-cycle arrest. Several proteins interacting with WRAP53 were identified through co-immunoprecipitation and liquid chromatography/mass spectrometry. These key proteins indicated previously undiscovered functions of WRAP53. These observations strongly suggested that WRAP53 should be considered a promising target in the prevention or treatment of lung adenocarcinoma.

Comparing Clinical Characteristics and Outcomes of Young-onset and Late-onset Colorectal Cancer: An International Collaborative Study

BACKGROUND

Compared with the general population, the incidence of young-onset (YO) colorectal cancer (CRC) is increasing. However, a significant knowledge gap exists in the clinical characteristics, treatment patterns, and outcomes for these patients.

MATERIALS AND METHODS

Six international tertiary cancer centers conducted a retrospective study. Patients with YO CRC (aged 18-44 years) and LO CRC (aged > 44 years) diagnosed with histologically proven colorectal adenocarcinoma from June 2003 to June 2014 were enrolled. Patients were randomly chosen from each center's database, and the patient demographics and treatment information were collected. The data were then centralized, and the final analysis was performed at a single institution. Cox proportional hazards models were used to estimate the crude and adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) for progression-free survival and mortality, and YO was compared with LO. Site-specific HRs were pooled using a random-effects meta-analysis.

RESULTS

Overall, 498 patients, including 224 with YO (129 men; mean age, 37 ± 5.5 years) and 274 with LO (167 men; mean age, 64.8 ± 9.5 years) CRC, were included. At the diagnosis, 137 patients (61.2%) and 122 patients (44.5%) with YO and LO CRC had metastatic disease, respectively. For both cohorts, the 3 most common presenting symptoms were pain, hematochezia, and weight loss. Surgery was performed in 141 YO (63.0%) and 219 LO (79.9%) patients. The longitudinal noncurative treatment patterns were similar, but more biologic therapy was used for these YO patients. The pooled progression-free survival analysis results for first-line noncurative treatment favored LO (HR, 1.96; 95% CI, 1.04-3.68). The mortality analysis showed no significant differences between the 2 groups (YO: HR, 1.53; 95% CI, 0.91-2.58).

CONCLUSION

Despite similar treatment patterns and survival outcomes, YO disease might be clinically more aggressive.

Unique prevalence of oncogenic genetic alterations in young patients with lung adenocarcinoma

BACKGROUND

Lung adenocarcinoma in the young is a rare entity, and the oncogenic genetic alterations (GAs) and clinical characteristics associated with this disease are poorly understood. Conversely, it has been demonstrated that young age at diagnosis defines unique biology in other cancers. For this report, the effects of young age on lung adenocarcinoma are reported.

METHODS

The authors retrospectively screened 1746 consecutive patients who were diagnosed with stage I through IV adenocarcinoma between 2009 and 2015 and identified 81 who were aged 40 years or younger at diagnosis. The clinical and genetic characteristics of this younger population were analyzed.

RESULTS

Of the 81 younger patients identified, 36 (44%) were men, 36 (44%) were never smokers, and the median age was 36 years (range, 26-40 years). Thirty-three patients (41%) harbored anaplastic lymphoma kinase (ALK) translocations, 24 (30%) had epidermal growth factor receptor (EGFR) mutations, and 2 (2%) had v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations. Rare oncogenic GAs also were studied in patients who had wild-type ALK/EGFR/KRAS adenocarcinoma, including 4 patients with HER2 mutations, 2 with Ret proto-oncogene (RET) translocations, and 2 with ROS proto-oncogene 1 receptor tyrosine kinase (ROS1) translocations. Notably, oncogenic GAs (P < .001), ALK (P < .001) and ROS1 (P = .033) translocations, and HER2 mutations (P < .001) were associated with young age, and a similar trend was observed for RET translocations (P = .108). Younger patients who had adenocarcinoma without GAs had a significantly worse prognosis compared with older patients without GAs (overall survival, 8.9 vs 16.4 months; P < .001) and patients with GAs (24.9 months; P < .001).

CONCLUSIONS

Younger patients with adenocarcinoma have a distinctly unique prevalence of oncogenic GAs. Comprehensive oncogenic GA screening is especially recommended for personalized medicine strategies in this population. Cancer 2017;123:1731-1740. © 2017 American Cancer Society.

Sulfonamide derivative targeting carbonic anhydrase IX as a nuclear imaging probe for colorectal cancer detection in vivo

Hypoxic microenvironment is a common situation in solid tumors. Carbonic anhydrase IX (CA9) is one of the reliable cellular biomarkers of hypoxia. The role of CA9 in colorectal cancer (CRC) remains to be clarified. CA9 inhibitor such as sulfonamides is known to block CA9 activation and reduce tumor growth consequently. Here, we aimed to investigate the CA9 expression in serum and tumor from different stages of CRC patients and utilize sulfonamide derivative with indium-111 labeling as a probe for CRC nuclear imaging detection in vivo. The serum CA9 was correlated with the tumor CA9 levels in different stages of CRC patients. Hypoxia increased cell viability and CA9 expression in colorectal cancer HCT-15 cells. Sulfonamide derivative 5-(2-aminoethyl)thiophene-2-sulfonamide (ATS) could bind with CA9 in vitro under hypoxia. Moreover, tumor tissues in HCT-15-induced xenograft mice possessed higher hypoxic fluorescence signal as compared with other organs. We also found that the radioisotope signal of indium-111 labeled ATS, which was utilized for CRC detection in HCT-15-induced xenograft mice, was markedly enhanced in tumors as compared with non-ATS control. Taken together, these findings suggest that CA9 is a potential hypoxic CRC biomarker and measurement of serum CA9 can be as a potential tool for diagnosing CA9 expressions in CRC clinical practice. The radioisotope-labeled sulfonamide derivative (ATS) may be useful to apply in CRC patients for nuclear medicine imaging.

Preoperative metabolic syndrome and prognosis after radical resection for colorectal cancer: The Fujian prospective investigation of cancer (FIESTA) study

This prospective study sought to investigate the prediction of preoperative metabolic syndrome and its components for the risk of colorectal cancer (CRC) mortality by analyzing a subset of data from the ongoing Fujian prospective investigation of cancer (FIESTA) study. In total, 1,318 CRC patients who received radical resection were consecutively enrolled between January 2000 and December 2008. The median follow-up time was 58.6 months, with 412 deaths from CRC. The CRC patients with metabolic syndrome had significantly shorter median survival time (MST) than those without (50.9 vs. 170.3 months, p < 0.001). Among four components of metabolic syndrome, hyperglycemia was the strongest predictor and its presence was associated with shorter MST than its absence (44.4 vs. 170.3 months, p < 0.001). Moreover, the complication of metabolic syndrome in CRC patients was associated with a 2.98-fold increased risk of CRC mortality (hazard ratio [HR] = 2.98, 95% confidence interval [CI]: 2.40-3.69, p < 0.001) after adjusting for confounding factors. The magnitude of this association was especially potentiated in CRC patients with tumor-node-metastasis stage I/II (HR = 3.94, 95% CI: 2.65-5.85, p < 0.001), invasion depth T1/T2 (HR = 5.41, 95% CI: 2.54-11.50, p < 0.001), regional lymph node metastasis N0 (HR = 4.06, 95% CI: 2.85-5.80, p < 0.001) and negative distant metastasis (HR = 3.23, 95% CI: 2.53-4.12, p < 0.001). Further survival tree analysis reinforced the prognostic capability of fasting blood glucose in CRC survival. Our findings convincingly demonstrated that preoperative metabolic syndrome, especially hyperglycemia, was a robust predictor for CRC mortality, and the protection was more obvious in patients with Stage I/II.

Association Between Younger Age and Targetable Genomic Alterations and Prognosis in Non-Small-Cell Lung Cancer

IMPORTANCE

Non-small-cell lung cancer (NSCLC) diagnosed in young patients is rare, and the genomics and clinical characteristics of this disease are poorly understood. In contrast, the diagnosis of other cancers at a young age has been demonstrated to define unique disease biology. Herein, we report on the association of young age with targetable genomic alterations and prognosis in a cohort of 2237 patients with NSCLC.

OBJECTIVE

To determine the relationship between young age at diagnosis and the presence of a potentially targetable genomic alteration, disease prognosis, and natural history.

DESIGN, SETTING, AND PARTICIPANTS

A cohort of all 2237 patients with NSCLC who were genotyped at the Dana-Farber Cancer Institute between January 2002 and December 2014 were identified. Tumor genotype, patient characteristics, and clinical outcomes were collected and studied at a National Cancer Institute-designated comprehensive cancer center. Multivariate logistic regression was used to analyze the relationship between age and mutation status, and multivariate Cox proportional hazard models were fitted for survival analysis.

MAIN OUTCOMES AND MEASURES

The frequency of targetable genomic alterations by defined age categories as well as the association of these age groups with survival. Age categories used in this analysis were younger than 40, 40 to 49, 50 to 59, 60 to 69, and 70 years or older.

RESULTS

A cohort of 2237 patients with NSCLC was studied. Of the 2237 participants, 1939 (87%) had histologically confirmed adenocarcinoma, 269 (12%) had NSCLC not otherwise specified, and 29 (1%) had squamous histologic findings; 1396 (63%) had either stage IIIB or IV cancers; and median (range) age was 62 (20-95) years. We found that gene mutations for EGFR (P = .02) and ALK (P < .001) were associated with cancer diagnosis at a younger age, and a similar trend existed for ERBB2 (P = .15) and ROS1 (P = .10) but not BRAF V600E (P = .43). Among patients tested for all 5 targetable genomic alterations (n = 1325), younger age was associated with an increased frequency of a targetable genotype (P < .001). Those diagnosed at 50 years or younger have a 59% increased likelihood of harboring a targetable genotype. While presence of a potentially targetable genomic alteration treated with a targeted agent was associated with improved survival, the youngest and oldest age groups had similarly poor outcomes even when a targetable genotype was present.

CONCLUSIONS AND RELEVANCE

Younger age is associated with an increased likelihood of harboring a targetable genotype and is an underappreciated clinical biomarker in NSCLC. The survival of young patients with NCSLC is unexpectedly poor compared with other age groups, suggesting more aggressive disease biology. These findings underscore the importance of comprehensive genotyping, including next-generation sequencing, in younger patients with lung cancer.

Colorectal cancer in the young, many questions, few answers

At a time where the incidence of colorectal cancer, a disease predominantly of developed nations, is showing a decline in those 50 years of age and older, data from the West is showing a rising incidence of this cancer in young individuals. Central to this has been the 75% increase in rectal cancer incidence in the last four decades. Furthermore, predictive data based on mathematical modelling indicates a 124 percent rise in the incidence of rectal cancer by the year 2030 - a statistic that calls for collective global thought and action. While predominance of colorectal cancer (CRC) is likely to be in that part of the large bowel distal to the splenic flexure, which makes flexible sigmoidoscopic examination an ideal screening tool, the cost and benefit of mass screening in young people remain unknown. In countries where the incidence of young CRC is as high as 35% to 50%, the available data do not seem to indicate that the disease in young people is one of high red meat consuming nations only. Improvement in our understanding of genetic pathways in the aetiology of CRC, chiefly of the MSI, CIN and CIMP pathway, supports the notion that up to 30% of CRC is genetic, and may reflect a familial trait or environmentally induced changes. However, a number of other germline and somatic mutations, some of which remain unidentified, may play a role in the genesis of this cancer and stand in the way of a clear understanding of CRC in the young. Clinically, a proportion of young persons with CRC die early after curative surgery, presumably from aggressive tumour biology, compared with the majority in whom survival after operation will remain unchanged for five years or greater. The challenge in the future will be to determine, by genetic fingerprinting or otherwise, those at risk of developing CRC and the determinants of survival in those who develop CRC. Ultimately, prevention and early detection, just like for those over 50 years with CRC, will determine the outcome of CRC in young persons. At present, aside from those with an established familial tendency, there is no consensus on screening young persons who may be at risk. However, increasing awareness of this cancer in the young and the established benefit of prevention in older persons, must be a message that should be communicated with medical students, primary health care personnel and first contact doctors. The latter constitutes a formidable challenge.

Cold-inducible proteins CIRP and RBM3, a unique couple with activities far beyond the cold

Cold-inducible RNA-binding protein (CIRP) and RNA-binding motif protein 3 (RBM3) are two evolutionarily conserved RNA-binding proteins that are transcriptionally upregulated in response to low temperature. Featuring an RNA-recognition motif (RRM) and an arginine-glycine-rich (RGG) domain, these proteins display many similarities and specific disparities in the regulation of numerous molecular and cellular events. The resistance to serum withdrawal, endoplasmic reticulum stress, or other harsh conditions conferred by RBM3 has led to its reputation as a survival gene. Once CIRP protein is released from cells, it appears to bolster inflammation, contributing to poor prognosis in septic patients. A variety of human tumor specimens have been analyzed for CIRP and RBM3 expression. Surprisingly, RBM3 expression was primarily found to be positively associated with the survival of chemotherapy-treated patients, while CIRP expression was inversely linked to patient survival. In this comprehensive review, we summarize the evolutionary conservation of CIRP and RBM3 across species as well as their molecular interactions, cellular functions, and roles in diverse physiological and pathological processes, including circadian rhythm, inflammation, neural plasticity, stem cell properties, and cancer development.