Genome-wide association studies and Mendelian randomization analyses provide insights into the causes of early-onset colorectal cancer

Stage-specific characterization of "early-onset colorectal cancer": Localized and synchronous metastatic disease

Early-onset colorectal cancer (EOCRC) is an alarming entity worldwide. Yet, stage-specific characteristics and prognosis in localized and synchronous metastatic EOCRC are not well-defined. Two cohorts of CRC patients (localized and synchronous metastatic) were evaluated, defining EOCRC as the diagnosis <50 years old. Five hundred sixty-eight patients were included (n = 432 localized, 14.4% [n = 62] EOCRC and n = 136 synchronous metastatic, 20.6% [n = 28] EOCRC). 93.5% of localized and 96.5% of synchronous metastatic EOCRC patients were symptomatic at diagnosis. Among localized patients, female gender (58.1% vs. 40%, p = .008), perineural invasion (41.9% vs. 24.9%, p = .005), folinic acid, 5-fluorouracil, and oxaliplatin chemotherapy (45.2% vs. 25.2%, p = .003), and perioperative chemotherapy cycles (9.21 [± 3.10] vs. 7.98 [± 2.92], p = .006) were higher in EOCRC compared with ≥50-year. Median recurrence-free survival (RFS) and overall survival were not reached in either group (p = .234 and p = .831). Only RAS mutant status was associated with RFS (Hazard ratio: 7.09 [95% confidence interval (CI): 1.87-26.76], p < .001) in EOCRC. Among synchronous metastatic patients, urgent surgery (32.1% vs. 11.1%, p = .014) and local treatments (39.3% vs. 20.4%, p = .037) were more frequent in EOCRC. Median progression-free survival and overall survival in the EOCRC and ≥50 years were 8.07 months (95% CI: 5.03-12.97) vs. 10.03 months (95% CI, 8.40-13.10) (p = .450) and 18.57 months (95% CI, 13.33-43.03) vs. 19.83 months (95% CI, 16.07-27.30) (p = .833), respectively. Synchronous metastatic EOCRC more frequently underwent urgent surgery (32.1% vs. 8%, p = .008) and had RAS mutation (43.5% vs. 16.7%, p = .032) than localized EOCRC. This study suggests that localized and synchronous metastatic EOCRC patients may have different characteristics than average onset, without survival differences. Implementation of stage-specific characteristics into daily practice is necessary for decision-making processes in these young patients.

Association of Genetic Liability to Allergic Diseases with Overall and Early-Onset Colorectal Cancer Risk: A Mendelian Randomization Study

BACKGROUND

The tumor immunosurveillance theory supports that allergic conditions could decrease cancer risk. However, observational evidence yielded inconsistent results for the association between allergic diseases and colorectal cancer risk. We used Mendelian randomization (MR) to examine potential causal associations of allergies with the risk of overall and early-onset colorectal cancer.

METHODS

Genome-wide association study summary statistical data were used to identify genetic variants associated with allergic diseases (Nvariants = 65) and individual allergic conditions (asthma, hay fever/allergic rhinitis, and eczema). Using two-sample MR, we examined these variants in relation to incident overall (Ncases = 52,775 cases) and early-onset colorectal cancer (Ncases = 6,176). The mediating role of white blood cells was examined using multivariable MR.

RESULTS

In inverse-variance-weighted models, genetic liability to allergic diseases was inversely associated with overall {OR per log (odds) = 0.90 [95% confidence interval (CI), 0.85-0.96]; P < 0.01} and early-onset colorectal cancer [OR = 0.83 (95% CI, 0.73-0.95); P = 0.01]. Similar inverse associations were found for hay fever/allergic rhinitis or eczema, whereas no evidence of association was found between liability to asthma-related phenotypes and colorectal cancer risk. Multivariable MR adjustment for eosinophils weakened the inverse associations for liability to allergic diseases for overall [OR = 0.96 (95% CI, 0.89-1.03); P = 0.26] and early-onset colorectal cancer [OR = 0.86 (95% CI, 0.73-1.01); P = 0.06].

CONCLUSIONS

Our study supports a potential causal association between liability to allergic diseases, specifically hay fever/allergic rhinitis or eczema, and colorectal cancer, possibly at least in part mediated via eosinophil counts.

IMPACT

Our results provide evidence that allergic responses may also have a role in immunosurveillance against colorectal cancer.

Identification of lncRNA biomarkers for keloid diagnosis and functional characterization of CPEB2-AS1

BACKGROUND

Keloids are pathological scars marked by excessive tissue growth, and their diagnosis currently depends on clinical observation, lacking objective biomarkers. Although the regulatory role of long non-coding RNAs (lncRNAs) in various diseases has drawn attention, their function in keloids remains unclear.

METHODS

This study employed high-throughput sequencing, bioinformatics analysis and machine learning algorithms to identify differentially expressed lncRNAs in keloid tissues and to construct a diagnostic model. The relationship between these lncRNAs and immune responses, as well as gene expression regulation, was explored through immune signature analysis and co-expression networks. The role of CPEB2-AS1 in keloids was investigated through expression validation, pan-cancer analysis and functional experiments.

RESULTS

Four key differentially expressed lncRNAs were identified, enabling the development of an effective diagnostic model that distinguishes keloid tissues from healthy controls. Immune signature analysis revealed a positive correlation between CPEB2-AS1 and immune cell activity. Co-expression networks and functional enrichment analysis suggested that these lncRNAs may regulate RNA processing and nucleic acid binding. Expression validation and pan-cancer analysis confirmed their abnormal expression in keloids. Functional experiments demonstrated that CPEB2-AS1 significantly influences cell proliferation, migration, invasion and apoptosis.

CONCLUSION

This study identifies new molecular markers for the early diagnosis of keloids and highlights the potential role of CPEB2-AS1 in keloid progression, offering insights for future therapeutic strategies.

Stress-testing US colorectal cancer screening guidelines: Decennial colonoscopy from age 45 is robust to natural history uncertainty and colonoscopy sensitivity assumptions

PurposeThe 2023 American College of Physicians (ACP) guidelines for colorectal cancer (CRC) screening are at odds with the United States Preventive Task Force (USPSTF) guidelines, with the former recommending screening starting at age 50 y and the latter at age 45 y. This article "stress tests" CRC colonoscopy screening strategies to investigate their robustness to uncertainties stemming from the natural history of disease and sensitivity of colonoscopy.MethodsThis study uses the CRC-SPIN microsimulation model to project the life-years gained (LYG) under several colonoscopy CRC screening strategies. The model was extended to include birth cohort effects on adenoma risk. We estimated natural history parameters under 2 different assumptions about the youngest age of adenoma initiation. For each, we generated 500 parameter sets to reflect uncertainty in the natural history parameters. We simulated 26 colonoscopy screening strategies and examined 4 different colonoscopy sensitivity assumptions, encompassing the range of sensitivities consistent with prior tandem colonoscopy studies. Across this set of scenarios, we identify efficient screening strategies and report posterior credible intervals for benefits of screening (LYG), burden (number of colonoscopies), and incremental burden-effectiveness ratios.ResultsProjected absolute screening benefits varied widely based on assumptions, but strategies starting at age 45 y were consistently in the efficiency frontier. Strategies in which screening starts at age 50 y with 10-y intervals were never efficient, saving fewer life-years than starting screening at age 45 y and performing colonoscopies every 15 y while requiring more colonoscopies per person.ConclusionsDecennial colonoscopy screening initiation at age 45 y remained a robust recommendation. Colonoscopy screening with a 10-y interval starting at age 50 y did not result in an efficient use of colonoscopies in any of the scenarios evaluated.HighlightsColorectal cancer colonoscopy screening strategies initiated at age 45 y were projected to yield more life-years gained while requiring the least number of colonoscopies across different model assumptions about disease natural history and colonoscopy sensitivity.Colonoscopy screening starting at age 50 y with a 10-y interval consistently underperformed strategies that started at age 45 y.

Integration of multi-omics data to unveil the molecular landscape and role of piRNAs in early-onset colorectal cancer

BACKGROUND

The incidence of early-onset colorectal cancer (EOCRC) (< 50 years) has been steadily rising, with a parallel increase in metastatic and invasive cases. To elucidate the molecular mechanisms underlying this aggressive phenotype, we performed comprehensive multi-omics profiling to delineate the distinct features of EOCRC, with a focus on key drivers of metastatic and invasive potential.

METHODS

We initially characterized the genome, epigenome, and transcriptome of tumors from 515 (69 EOCRC and 446 late-onset CRC [LOCRC]) cases in The Cancer Genome Atlas. Key candidate molecules were further validated using RNA-seq and scRNA-seq data. Multi-omics profiling revealed PIWIL1/piRNA as a hallmark of EOCRC, with further validation through in vitro functional assays, transcriptomic profiling, and Kaplan-Meier survival analysis.

RESULTS

EOCRC demonstrated a mutational landscape similar to that of LOCRC, with comparable oncogenic driver mutations and somatic copy-number alterations. However, EOCRC exhibited a higher frequency of deletion in chromosomes 6, 15, and 19 regions, along with metabolic reprogramming favoring aerobic glycolysis and lipid metabolism. Integrative transcriptomic and DNA methylation analyses identified six EOCRC-specific molecules, including PIWIL1. Notably, PIWIL1 was mainly expressed in epithelial cells, with lower expression in EOCRC versus LOCRC. Its downstream piRNAs (FR019019, FR019089, and FR132045) were also downregulated in EOCRC. Functional experiments demonstrated that FR019089/FR019019 overexpression suppressed migration and invasion. Clinically, low FR019089 levels correlated with significantly shorter progression-free and overall survival in EOCRC patients. Additionally, downstream pathways of FR019089 and FR019019 overexpression were enriched in anti-cancer-related signaling pathways.

CONCLUSIONS

Our multi-omics approach yields novel insights into the molecular underpinnings of EOCRC and we characterize the role of PIWIL1-associated piRNAs in modulating EOCRC metastasis and invasion. FR019089 shows promise as a prognostic biomarker with potential clinical utility in the risk stratification and management of EOCRC patients.

Investigating the causal relationship between immune cells and colorectal cancer risk using bidirectional and multivariable Mendelian randomization analysis

OBJECTIVES

This study explores the relationship between immune recognition diversity and colorectal cancer (CRC) risk using a bidirectional Mendelian randomization approach.

METHODS

Genetic data from 731 immune cell types were analyzed, with data sourced from the IEU and FinnGen databases and CRC data from genome-wide association studies on the Finnish population. Forward and reverse Mendelian randomization analyses were conducted, with sensitivity analyses to assess pleiotropic effects.

RESULTS

Analyses revealed a significant association between increased Effector Memory CD4 and CD8 T cells and higher CRC risk (odds ratio [OR] = 1.11, 95% confidence interval [CI] = 1.04-1.18, p = .0008). Conversely, elevated CD45 on natural killer T cells was associated with a lower CRC risk (OR = 0.93, 95% CI = 0.88-0.98, p = .0095), indicating a protective effect. Sensitivity analyses confirmed no pleiotropic effects.

CONCLUSIONS

These findings highlight specific immune cells' roles in CRC pathogenesis, suggesting potential avenues for immune-targeted therapies and CRC prevention. Given the rising global incidence of CRC, understanding immune cell roles is crucial for advancing effective treatments.

Decoding the genetic and environmental forces in propelling the surge of early-onset colorectal cancer

ABSTRACT

Early-onset colorectal cancer (EOCRC) shows a different epidemiological trend compared to later-onset colorectal cancer, with its incidence rising in most regions and countries worldwide. However, the reasons behind this trend remain unclear. The etiology of EOCRC is complex and could involve both genetic and environmental factors. Apart from Lynch syndrome and Familial Adenomatous Polyposis, sporadic EOCRC exhibits a broad spectrum of pathogenic germline mutations, genetic polymorphisms, methylation changes, and chromosomal instability. Early-life exposures and environmental risk factors, including lifestyle and dietary risk factors, have been found to be associated with EOCRC risk. Meanwhile, specific chronic diseases, such as inflammatory bowel disease, diabetes, and metabolic syndrome, have been associated with EOCRC. Interactions between genetic and environmental risk factors in EOCRC have also been explored. Here we present findings from a narrative review of epidemiological studies on the assessment of early-life exposures, of EOCRC-specific environmental factors, and their interactions with susceptible loci. We also present results from EOCRC-specific genome-wide association studies that could be used to perform Mendelian randomization analyses to ascertain potential causal links between environmental factors and EOCRC.

Molecular Heterogeneity in Early-Onset Colorectal Cancer: Pathway-Specific Insights in High-Risk Populations

BACKGROUND/OBJECTIVES

The incidence of early-onset colorectal cancer (EOCRC), defined as diagnosis before age 50, has been rising at an alarming rate, with Hispanic/Latino (H/L) individuals experiencing the most significant increases in both incidence and mortality. Despite this growing public health concern, the molecular mechanisms driving EOCRC disparities remain poorly understood. Oncogenic pathways such as WNT, TGF-beta, and RTK/RAS are critical in colorectal cancer (CRC) progression, yet their specific roles in EOCRC across diverse populations have not been extensively studied. This research seeks to identify molecular alterations within these pathways by comparing EOCRC cases in H/L and non-Hispanic White (NHW) individuals. Furthermore, we explore the clinical significance of these findings to inform precision medicine strategies tailored to high-risk populations.

METHODS

To investigate mutation frequencies in genes associated with the WNT, TGF-beta, and RTK/RAS pathways, we conducted a bioinformatics analysis using publicly available CRC datasets. The study cohort consisted of 3412 patients, including 302 H/L and 3110 NHW individuals. The patients were categorized based on age (EOCRC: <50 years; late-onset CRC [LOCRC]: ≥50 years) and population group (H/L vs. NHW) to assess variations in mutation prevalence. Statistical comparisons of mutation rates between the groups were conducted using chi-squared tests, while Kaplan-Meier survival analysis was employed to evaluate overall survival differences associated with pathway alterations.

RESULTS

Notable molecular distinctions in the RTK/RAS pathway were identified between EOCRC and LOCRC among the H/L patients, with EOCRC exhibiting a lower frequency of RTK/RAS alterations compared to LOCRC (66.7% vs. 79.3%, p = 0.01). Within this pathway, mutations in CBL (p < 0.05) and NF1 (p < 0.05) were significantly more prevalent in the EOCRC cases (5.8% vs. 1.2% and 11.6% vs. 3.7%, respectively), whereas BRAF mutations were notably less frequent in EOCRC than in LOCRC (5.1% vs. 18.3%, p < 0.05). Comparisons between the EOCRC patients from the H/L and NHW populations revealed distinct pathway-specific alterations that were more common in the H/L individuals. These included RNF43 mutations (12.3% vs. 6.7%, p < 0.05) in the WNT pathway, BMPR1A mutations (5.1% vs. 1.8%, p < 0.05) in the TGF-beta pathway, and multiple RTK/RAS pathway alterations, such as MAPK3 (3.6% vs. 0.7%, p < 0.05), CBL (5.8% vs. 1.4%, p < 0.05), and NF1 (11.6% vs. 6.1%, p < 0.05). Survival analysis in the H/L EOCRC patients did not reveal statistically significant differences based on pathway alterations. However, in the NHW EOCRC patients, the presence of WNT pathway alterations was associated with significantly improved survival outcomes, suggesting potential ethnicity-specific prognostic implications.

CONCLUSIONS

This study highlights the substantial molecular heterogeneity present in EOCRC, particularly among high-risk populations. The H/L EOCRC patients exhibited distinct genetic alterations, with a higher prevalence of CBL, NF1, RNF43, BMPR1A, and MAPK3 mutations compared to their NHW counterparts. Additionally, RTK/RAS pathway alterations were less frequent in EOCRC than in LOCRC. Despite these molecular differences, pathway alterations did not significantly impact survival outcomes in the H/L EOCRC patients. However, in the NHW EOCRC patients, the presence of WNT pathway alterations was associated with improved survival. These findings emphasize the necessity for further research to clarify the molecular mechanisms driving EOCRC disparities in high-risk populations and to inform precision medicine strategies for underrepresented groups.

Young-onset metastatic colorectal cancer: an opportunity and a vision for progress in cancer

Metastatic young-onset colorectal cancer (yo-CRC) is a distinct and aggressive disease subtype that is becoming increasingly prevalent worldwide with Australia leading the world in this trend. This article provides an evidence-based perspective, through the prism of authors' personal experience, to craft an effective pathway not only to deliver improved outcomes for the patients but also to reduce disparities and foster collaboration amongst the cancer-treating community and indeed patients. It highlights an opportunity to re-define, re-design, and create a model that is rewarding to patients and cancer-treating community. Although our focus is on the high unmet needs group of yo-CRC, this model has the potential to expand to other cancer types and care models. We analyse the unique epidemiological trends, challenges, and burdens, emphasising the need for tailored treatment approaches for younger patients with colorectal cancer especially in the metastatic setting. We identify current gaps in clinical practice and research. To improve real-world outcomes, we propose a conceptual framework to enhance clinician-patient communication and treatment planning. Central to our approach is the integration of a Registry of Incidence, Intervention, and Outcomes (RIIO), which enables real-time data collection and analysis, improving treatment personalisation and efficacy. This registry could revolutionise patient care and drive research innovation through enhanced data sharing and collaboration. We advocate for a patient-centric integrated care model that utilises all available therapies to maximise survival and quality of life. Our perspective underscores the urgent need for a paradigm shift in how yo-CRC is viewed, researched and managed, proposing a pathway to significantly enhanced outcomes. Whilst it is feasible to expand the concepts discussed here for all colorectal cancer and indeed all cancer types, we believe this approach is most relevant and acutely needed in yo-CRC setting for reasons detailed in the manuscript.

Investigating the causal relationship between skin microbiota and hypertrophic scar using bidirectional mendelian randomization

BACKGROUND

Hypertrophic scar (HS) is acknowledged as a pathological fibro-proliferative disease of the dermis, resulting from excessive connective tissue growth. HS significantly impacts patient quality of life due to both social and functional issues. Despite various treatments, therapeutic effectiveness remains limited, necessitating further exploration of underlying factors and mechanisms.

OBJECTIVE

The current study was designed to determine the causal relationship between skin microbiota and HS employing a bidirectional Mendelian randomization (MR) approach.

METHODS

We utilized genome-wide association study (GWAS) data from the PopGen cohort and the FinnGen database. Independent single nucleotide polymorphisms (SNPs) linked to the skin microbiota were identified as instrumental variables (IVs) chosen for the two-sample MR analysis. Key analytical approaches included inverse variance weighting (IVW), MR-Egger, simple median, simple mode, and weighted mode, with MR-Egger intercept test and Cochrane's Q test used to detect potential horizontal pleiotropy and heterogeneity.

RESULTS

The two-sample MR analysis identified significant causal relationships between specific skin microbiota features and HS. Notably, Enhydrobacter, Micrococcus, and Acinetobacter on moist skin exhibited protective effects against HS, whereas Finegoldia and Lactobacillales on dry skin were linked to an increased risk of HS. Sensitivity analyses verified the strength of these results, revealing no notable horizontal pleiotropy or heterogeneity.

CONCLUSION

Our research reveals a unidirectional causal relationship between certain skin microbiota and HS, suggesting that modulation of skin microbiota could be a novel therapeutic approach for HS management. These results emphasize the significance of considering skin microbiota in the pathogenesis and treatment of HS.

Discovery of new imidazole[1,2-a] pyridine derivatives as CDK9 inhibitors: design, synthesis and biological evaluation

Colorectal cancer (CRC) is a highly aggressive and extensive malignancy. Presently, targeting the transcriptional regulation of cyclin-dependent kinase 9 (CDK9) is a promising therapeutic approach. Herein, twenty-five compounds (LA-1-LA-13 and LB-1-LB-12) were designed and synthesized with AZD5438 as the lead compound using an imidazole[1,2-a] pyridine skeleton. Compound LB-1 exhibited potent CDK9 inhibition and induced apoptosis in the HCT116 cell line. Moreover, compared with AZD5438, LB-1 demonstrated highly selective CDK9 inhibitory activity, with an IC50 value of 9.22 nM. Accordingly, compound LB-1 could be further developed as a selective, target-oriented CDK9 inhibitor for colorectal cancer.

Rethinking the rise of early-onset gastrointestinal cancers: a call to action

Since the early 1990s, there has been a dramatic rise in gastrointestinal cancers diagnosed in patients under age 50 for reasons that remain poorly understood. The most significant change has been the increase in incidence rates of early-onset colorectal cancer, especially rates of left-sided colon and rectal cancers. Increases in gastric, pancreatic, and other gastrointestinal cancer diagnoses have further contributed to this trend. We formed a multidisciplinary Think Tank to develop a strategic, coordinated approach to studying early-onset gastrointestinal cancers. This area of research is challenging given multifactorial etiologies. We focused on epidemiology and the environment, the microbiome, and survivorship as key pillars to structure a research framework. We advocate a comprehensive strategy to (1) use existing biospecimens, especially those collected longitudinally, with correlation to exposures (the exposome); (2) standardize microbiome specimen collection and analyses of blood, tissue, and stool specimens to minimize contamination and biases; (3) prioritize mechanistic studies to evaluate findings from biomarker studies; and (4) explore the unique survivorship needs of this young population. These recommendations build upon prior efforts with the goal of streamlining research into this important field of study while minimizing redundant efforts. We hope that our findings serve as a clarion call to motivate others to discover why young individuals are being diagnosed with gastrointestinal cancers at such an alarming rate and how to best support those who have been diagnosed.

Genetically Predicted Gut Microbiota Mediate the Association Between Fatty Acids and Intrahepatic Cholestasis of Pregnancy: A Mendelian Randomization Analysis

Fatty acids (FAs) and gut bacteria likely play vital roles in intrahepatic cholestasis of pregnancy (ICP). However, the causal connection between FAs, gut microbiota, and ICP has not yet been confirmed. To investigate the associations of FAs, gut bacteria, and ICP, a Mendelian randomization (MR) analysis with two samples was performed to identify the potential causal relationships between FAs and ICP. The potential mediating role of gut bacteria in FAs and ICP was analyzed by a two-step MR analysis. False discovery rate (FDR) correction was conducted to correct the bias of multiple tests. MR analysis revealed that higher omega-6 FAs/total FAs (odds ratio [OR] = 2.563, 95% confidence interval [CI] = 1.362-4.824, FDR p = 0.016), linoleic acids/total FAs (OR = 3.812, 95%CI = 1.966-7.388, FDR p = 0.001), and average number of methylene groups (OR = 1.968, 95%CI = 1.390-2.785, FDR p = 0.001) are potential risk factors for ICP. However, omega-3 FAs (OR = 0.587, 95%CI = 0.394-0.874, FDR p = 0.031) and the average number of double bonds in an FA chain (OR = 0.575, 95%CI = 0.435-0.759, FDR p = 0.001) could reduce the risk of ICP. The abundance of 25 gut bacteria showed significant causal effects on ICP, among which Dokdonella may play a crucial role in modulating the effects of FAs on ICP. Our research results suggest that the effects of FA on ICP likely vary according to their different types. Dokdonella abundance plays a significant role in mediating the causal interactions between FAs and ICP.

Plasma Ghrelin and Risks of Sex-Specific, Site-Specific, and Early-Onset Colorectal Cancer: A Mendelian Randomization Analysis

BACKGROUND

Epidemiological and laboratory-based studies have provided conflicting evidence for a role of ghrelin in colorectal cancer development. We conducted two-sample Mendelian randomization (MR) analyses to evaluate evidence for an association of circulating ghrelin and colorectal cancer risk overall and by sex, cancer subsite, and age at diagnosis.

METHODS

Genetic instruments proxying plasma total ghrelin levels were obtained from a recent genome-wide association study of 54,219 participants. Summary data for colorectal cancer risk were obtained from a recent meta-analysis of several genetic consortia (up to 73,673 cases and 86,854 controls). A two-sample MR approach and several sensitivity analyses were applied.

RESULTS

We found no evidence for an association of genetically predicted plasma total ghrelin levels and colorectal cancer risk (0.95, 95% confidence interval, 0.81-1.12; R2 of ghrelin genetic instruments: 4.6%), with similarly null results observed when stratified by sex, anatomical subsite, and for early-onset colorectal cancer.

CONCLUSIONS

Our study suggests that plasma ghrelin levels are unlikely to have a causal relationship with overall, early-onset, and sex- and cancer subsite-stratified colorectal cancer risk.

IMPACT

This large-scale analysis adds to the growing body of evidence that plasma total ghrelin levels are not associated with colorectal cancer risk.

Impact of chronic stress on intestinal mucosal immunity in colorectal cancer progression

Chronic stress is a significant risk factor that contributes to the progression of colorectal cancer (CRC) and has garnered considerable attention in recent research. It influences the distribution and function of immune cells within the intestinal mucosa through the "brain-gut" axis, altering cytokine and chemokine secretion and creating an immunosuppressive tumor microenvironment. The intestine, often called the "second brain," is particularly susceptible to the effects of chronic stress. Cytokines and chemokines in intestinal mucosal immunity（IMI） are closely linked to CRC cells' proliferation, metastasis, and drug resistance under chronic stress. Recently, antidepressants have emerged as potential therapeutic agents for CRC, possibly by modulating IMI to restore homeostasis and exert anti-tumor effects. This article reviews the role of chronic stress in promoting CRC progression via its impact on intestinal mucosal immunity, explores potential targets within the intestinal mucosa under chronic stress, and proposes new approaches for CRC treatment.

Early Onset Colorectal Cancer: Molecular Underpinnings Accelerating Occurrence

The onset of colorectal cancer (CRC) in patients younger than 50 continues to rapidly increase. This study highlights the epidemiologic changes, risk factors, clinical characteristics, and molecular profiles prevalent in early onset CRC patients, and identifies key areas for future research. It has been noted that only a small fraction of early onset CRC cases is attributed to known hereditary mutations and fit the canonical pathway of late-onset colorectal cancer development. To highlight this, we review the genetic and epigenetic modifications specific to early onset CRC. We also discuss the synergetic effect of single-nucleotide polymorphisms and environmental factors on the early onset of CRC. Additionally, we discuss the potential of noninvasive biomarker assays to enhance early detection, screening, diagnosis, and prognostic outcome predictions.

Early-Onset colorectal Cancer: From the laboratory to the clinic

Colorectal cancer that occurs before age of 50 is defined as Early-Onset Colorectal Cancer (EOCRC). Its incidence has worryingly increased since the late 90 s and is expected to keep rising in the next future, despite Late-Onset CRC (LOCRC) is decreasing worldwide. Because of this, there is an urgent need to better understand this subset of patients in order to give them the best treatment possible. However, most of the literature is retrospective and often discordant. In this review, we aim to provide a general overview of the issue, endeavoring to highlight the current available knowledge. We decided to move from the beginning, investigating risk factors and inheritance, passing through diagnosis and clinical aspects, and to conclude with the translational part, focusing on the biology of the tumor. However, lot of questions remain open, including screening age and prognosis. Indeed, young patients tend to be treated more aggressively, even if a survival benefit has not been proven yet. Every clinician should be aware of the best practice for young people, and more translational studies are awaited in order to clarify is EOCRC represents a distinct biological entity.

Causal effect of thyroid cancer on secondary primary malignancies: findings from the UK Biobank and FinnGen cohorts

Background

Existing epidemiological data indicated a correlation between thyroid cancer (THCA) and the risk of secondary primary malignancies (SPMs). However, the correlation does not always imply causality.

Methods

The Mendelian randomization (MR) analyses were performed to investigate the causal relationships between THCA and SPMs based on international multicenter data. Odds ratios (ORs) with 95% confidence intervals (95% CIs) were calculated. The Cancer Genome Atlas (TCGA) was used to explore potential mechanisms shared by THCA and bladder cancer (BLCA).

Results

Summary datasets of genome-wide association studies (GWAS) on 30 types of cancers were obtained from the United Kingdom Biobank (UKB) and FinnGen database. Meta-analysis of the UKB and FinnGen results revealed that THCA was significantly positively correlated with BLCA (OR = 1.140; 95% CI, 1.072-1.212; P < 0.001). Four genes, including WNT3, FAM171A2, MLLT11, and ULBP1, were identified as key genes shared by both TCHA and BLCA. Correlation analysis indicated that THCA may increase the risk of secondary BLCA through augmentation of N2 neutrophil infiltration.

Conclusions

This study showed that THCA was causally related to BLCA. It is recommended to conduct more rigorous screenings for BLCA during the follow-up of THCA patients.

Obesity and early-onset colorectal cancer risk: emerging clinical evidence and biological mechanisms

Early-onset colorectal cancer (EOCRC) is defined as diagnosed at younger than 50 years of age and indicates a health burden globally. Patients with EOCRC have distinct risk factors, clinical characteristics, and molecular pathogenesis compared with older patients with CRC. Further investigations have identified different roles of obesity between EOCRC and late-onset colorectal cancer (LOCRC). Most studies have focused on the clinical characteristics of obesity in EOCRC, therefore, the mechanism involved in the association between obesity and EOCRC remains inconclusive. This review further states that obesity affects the carcinogenesis of EOCRC as well as its development and progression, which may lead to obesity-related metabolic syndrome, intestinal dysbacteriosis, and intestinal inflammation.