Risk factors including night shift work of colorectal polyp

Establishment and validation of a clinical prediction model for colorectal adenoma risk factors

Colorectal adenomas are benign tumors of the colorectal mucosal epithelium that have malignant potential and are regarded as precancerous lesions of colorectal cancer, for which the specific risk factors are unclear. The present study aimed to identify independent risk factors for colorectal adenoma to develop a prediction model and test its predictive value. A retrospective analysis was performed using data from patients who underwent electronic colonoscopy at the Department of Proctology (Affiliated Hospital of Shandong University of Traditional Chinese Medicine; Jinan, China) from January 2013 to December 2023 and had polyps removed during colonoscopy. Patients with colorectal adenoma were included in the case group, whilst those with no visible abnormalities on endoscopy or with non-adenomatous polyps were included as a control group. The patients were randomly divided into a training and validation group in a 7:3 ratio. Variables were screened using single-component analysis and the filtered variables were employed in multivariate logistic regression to create a clinical prediction model. Finally, the model was internally and externally validated. A total of 730 patients were included in the present study, with 286 assigned to the case group and 444 to the control group. After the initial screening of 39 variables, 12 continued to the next round, resulting in four potential predictors including age, daily number of bowel movements, thrombin time and the number of polyps. A prediction model was created based on these variables. Regarding internal validation, the C-index was 0.7054 [95% confidence interval (CI), 0.6596-0.7512] and the prediction probability in the calibration curve was close to the diagonal line of the calibration graph, indicating that the prediction probability of the model was reasonable. Regarding external validation, the C-index in the validation cohort was 0.6306 (95% CI, 0.5560-0.7053) and the calibration curve also demonstrated good identification capabilities. The Hosmer-Lemeshow test revealed that the model had a reasonable calibration degree, with χ2=9.7893, degree of freedom=8 and P=0.28. The receiver operating characteristic curve and decision curve analysis for the training and validation cohorts demonstrated good efficacy and an ideal application value. In conclusion, the model constructed in the present study demonstrated moderate predictive accuracy for colorectal adenoma risk, laying the groundwork for early detection of colorectal adenoma and secondary prevention of colorectal cancer.

Nurse night shift work and risk of gastrointestinal cancers

The prevalence of night-shift employment is on the rise among full-time and part-time workers globally. Those engaged in night-shift work encounter various biological challenges, including exposure to artificial light during nighttime and disruptions to their circadian rhythms. These factors, along with changes in daily routines and activities, may pose significant risks to the health of night workers. Notably, the number of individuals working overtime or on night shifts has increased across various sectors, particularly in transportation, healthcare, and manufacturing. The International Agency for Research on Cancer (IARC) has classified night-shift work as probably carcinogenic to humans (IARC Group 2A). Subsequent research has identified several potential mechanisms through which night-shift work may contribute to carcinogenicity: (1) disruption of circadian rhythms, (2) suppression of melatonin levels due to nighttime light exposure, (3) physiological alterations, (4) lifestyle changes, and (5) reduced vitamin D levels resulting from inadequate sunlight exposure. Colorectal cancer (CRC) poses a significant public health challenge, ranking as the second leading cause of cancer-related death worldwide in 2020. Other than CRC, other gastrointestinal cancers are also creating a great global health issue because of their morbidity and mortality rates. In this review, we highlight the role of night shifts in disturbing circadian rhythm and how this action leads to carcinogenesis in the GI tract.

Spatial clustering of colorectal cancer in Malaysia

INTRODUCTION

The rise in colorectal cancer (CRC) incidence becomes a global concern. As geographical variations in the CRC incidence suggests the role of area-level determinants, the current study was designed to identify the spatial distribution pattern of CRC at the neighbourhood level in Malaysia.

METHOD

Newly diagnosed CRC cases between 2010 and 2016 in Malaysia were identified from the National Cancer Registry. Residential addresses were geocoded. Clustering analysis was subsequently performed to examine the spatial dependence between CRC cases. Differences in socio-demographic characteristics of individuals between the clusters were also compared. Identified clusters were categorized into urban and semi-rural areas based on the population background.

RESULT

Most of the 18 405 individuals included in the study were male (56%), aged between 60 and 69 years (30.3%) and only presented for care at stages 3 or 4 of the disease (71.3%). The states shown to have CRC clusters were Kedah, Penang, Perak, Selangor, Kuala Lumpur, Melaka, Johor, Kelantan, and Sarawak. The spatial autocorrelation detected a significant clustering pattern (Moran's Index 0.244, p< 0.01, Z score >2.58). CRC clusters in Penang, Selangor, Kuala Lumpur, Melaka, Johor, and Sarawak were in urbanized areas, while those in Kedah, Perak and Kelantan were in semi-rural areas.

CONCLUSION

The presence of several clusters in urbanized and semi-rural areas implied the role of ecological determinants at the neighbourhood level in Malaysia.  Such findings could be used to guide the policymakers in resource allocation and cancer control.

Circadian regulation of digestive and metabolic tissues

The circadian clock is a self-sustained molecular timekeeper that drives 24-h (circadian) rhythms in animals. The clock governs important aspects of behavior and physiology including wake/sleep activity cycles that regulate the activity of metabolic and digestive systems. Light/dark cycles (photoperiod) and cycles in the time of feeding synchronize the circadian clock to the surrounding environment, providing an anticipatory benefit that promotes digestive health. The availability of animal models targeting the genetic components of the circadian clock has made it possible to investigate the circadian clock's role in cellular functions. Circadian clock genes have been shown to regulate the physiological function of hepatocytes, gastrointestinal cells, and adipocytes; disruption of the circadian clock leads to the exacerbation of liver diseases and liver cancer, inflammatory bowel disease and colorectal cancer, and obesity. Previous findings provide strong evidence that the circadian clock plays an integral role in digestive/metabolic disease pathogenesis, hence, the circadian clock is a necessary component in metabolic and digestive health and homeostasis. Circadian rhythms and circadian clock function provide an opportunity to improve the prevention and treatment of digestive and metabolic diseases by aligning digestive system tissue with the 24-h day.

Do sleep quality and psychological factors link precancerous conditions of colorectal cancer? A retrospective case-control study

BACKGROUND

Little is known about the effect of sleep quality on the risk of precancerous conditions of colorectal cancer (PCRC). The role of psychological factors, including stress, resilience, and social support as closely related factors of sleep quality, was also discussed.

RESEARCH DESIGN AND METHODS

Fifty-one patients with PCRC were compared with two control groups during the previous year in a retrospective case-control analysis: 74 patients with colorectal cancer and 145 healthy controls. Participants completed questionnaires measuring sleep quality, perceived stress, resilience, and social support one year prior to disease diagnosis. Univariate and multivariate logistic regression models were used to analyze the data.

RESULTS

Increased risk of PCRC was associated with sleep disturbance≥2 and the negative factors of stress ≥14 compared with healthy controls. Decreased risk of PCRC was associated with resilience ≥31 and family support ≥18. In a multivariate model, sleep disturbance≥2 was significantly associated with an elevated risk of PCRC (OR = 20.15, 95% CI: 4.22 to 96.26).

CONCLUSIONS

Physicians should be aware of the strong association between sleep disturbance≥2 and the increased risk for PCRC and explain the need for colonoscopy in patients with sleep disturbance≥2.

Prevalence of Colorectal Polyps Based on Cardiorespiratory Fitness, Muscle Strength, Health Behavior, and Abdominal Obesity in Asymptomatic Elderly

Colorectal polyps are precursor lesions of colorectal cancer and are known to be associated with obesity, low physical activity, and unhealthy behavior. This cross-sectional study analyzed the prevalence of colorectal polyps based on cardiorespiratory fitness (CRF), muscle strength, and health behavior in older adults. Participants were asymptomatic and included 1024 men and 472 women aged 65-80 years who visited the health care center. Colonoscopy was performed under conscious sedation, and cardiorespiratory fitness was measured as the maximum oxygen uptake using gas analysis. Muscle strength was determined using isokinetic equipment, and physical activity, alcohol consumption, and smoking status were investigated using questionnaires. Waist circumference was measured at the thickest part of the middle of the abdomen. Logistic regression analysis was used to calculate the prevalence of colorectal polyps using odds ratios (ORs) based on the variables. The incidence of colorectal polyps was 65.2% in men and 48.5% in women. The ORs of colorectal polyps for obesity were 1.151 (95% confidence interval [CI], 1.010-2.291) and 1.178 (95% CI, 1.015-2.612) in men and women, respectively. The OR for colorectal polyps in male current smokers was 1.884. The ORs for low CRF were 1.985 and 1.841 in men and women, respectively, compared with high CRF. The prevalence of polyps increased with low muscle strength (men's OR 1.343 women's OR 1.440) and physical activity in both men (OR 1.693) and women (OR 1.861). In conclusion, lower CRF and muscle strength were associated with an increased prevalence of colorectal polyps in men and women. In both sexes, high waist circumference and low physical activity increased the prevalence of colorectal polyps.

The Circadian Clock Gene, Bmal1, Regulates Intestinal Stem Cell Signaling and Represses Tumor Initiation

BACKGROUND & AIMS

Circadian rhythms are daily physiological oscillations driven by the circadian clock: a 24-hour transcriptional timekeeper that regulates hormones, inflammation, and metabolism. Circadian rhythms are known to be important for health, but whether their loss contributes to colorectal cancer is not known. We tested the nonredundant clock gene Bmal1 in intestinal homeostasis and tumorigenesis, using the Apcmin model of colorectal cancer.

METHODS

Bmal1 mutant, epithelium-conditional Bmal1 mutant, and photoperiod (day/night cycle) disrupted mice bearing the Apcmin allele were assessed for tumorigenesis. Tumors and normal nontransformed tissue were characterized. Intestinal organoids were assessed for circadian transcription rhythms by RNA sequencing, and in vivo and organoid assays were used to test Bmal1-dependent proliferation and self-renewal.

RESULTS

Loss of Bmal1 or circadian photoperiod increases tumor initiation. In the intestinal epithelium the clock regulates transcripts involved in regeneration and intestinal stem cell signaling. Tumors have no self-autonomous clock function and only weak clock function in vivo. Apcmin clock-disrupted tumors show high Yes-associated protein 1 (Hippo signaling) activity but show low Wnt (Wingless and Int-1) activity. Intestinal organoid assays show that loss of Bmal1 increases self-renewal in a Yes-associated protein 1-dependent manner.

CONCLUSIONS

Bmal1 regulates intestinal stem cell pathways, including Hippo signaling, and the loss of circadian rhythms potentiates tumor initiation. Transcript profiling: GEO accession number: GSE157357.