Design of the Building Research in CRC prevention (BRIDGE-CRC) trial: a 6-month, parallel group Mediterranean diet and weight loss randomized controlled lifestyle intervention targeting the bile acid-gut microbiome axis to reduce colorectal cancer risk among African American/Black adults with obesity

Effects of invigorating-spleen and anticancer prescription on extracellular signal-regulated kinase/mitogen-activated protein kinase signaling pathway in colon cancer mice model

BACKGROUND

Colon cancer (CC) is one of the most common malignant tumors in the gastrointestinal system. Overall, CC had the third highest incidence but the second highest mortality rate globally in 2020. Nowadays, CC is mainly treated with capecitabine chemotherapy regimen, supplemented by radiotherapy, immunotherapy and targeted therapy, but there are still limitations, so Chinese medicine plays an important role.

AIM

To investigate the effects of invigorating-spleen and anticancer prescription (ISAP) on body weight, tumor inhibition rate and expression levels of proteins in extracellular-signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) signaling pathway in CC mice model.

METHODS

The CC mice model were established and the mice were randomly divided into 5 groups, including the control group, capecitabine group, the low-dose, medium-dose and high-dose groups of ISAP, with 8 mice in each group, respectively. After 2 weeks of intervention, the body weight and tumor inhibition rate of mice were observed, and the expression of RAS, ERK, phosphorylated ERK (p-ERK), C-MYC and matrix metalloproteinase 2 (MMP2) proteins in the tissues of tumors were detected.

RESULTS

Compared with the control group, the differences of body weight before and after treatment was much smaller in the groups of ISAP, with the smallest difference in the high-dose group of ISAP, while the capecitabine group had the greatest difference, indicating ISAP had a significant inhibiting effect on the growth of transplanted tumor in mice. The expression of RAS protein was decreased in the low- and medium-dose groups of ISAP, and the change of p-ERK was significant in the medium- and high- dose groups of ISAP. MMP2 protein expression was significantly decreased in both the low-dose and medium-dose groups of ISAP. There were no significant changes in ERK in the ISAP group compared to the capecitabine group, while RAS, MMP2, and C-MYC protein expression were reduced in the ISAP group. The expression level of C-MYC protein decreased after treated with ISAP, and the decrease was the most significant in the medium-dose group of ISAP.

CONCLUSION

ISAP has a potential inhibiting effect on transplanted tumor in mice, and could maintain the general conditions, physical strength and body weight of mice. The expression levels of RAS, p-ERK, MMP2 and c-myc were also decreased to a certain extent. By inhibiting the expression of upstream proteins, the expression levels of downstream proteins in ERK/MAPK signaling pathway were significantly decreased. Therefore, it can be concluded that ISAP may exert an anti-tumor effect by blocking the ERK/MAPK signaling pathway and inhibiting the expression of MMP2 and c-myc proteins.

Novel perspectives on the link between obesity and cancer risk: from mechanisms to clinical implications

Existing epidemiologic and clinical studies have demonstrated that obesity is associated with the risk of a variety of cancers. In recent years, an increasing number of experimental and clinical studies have unraveled the complex relationship between obesity and cancer risk and the underlying mechanisms. Obesity-induced abnormalities in immunity and biochemical metabolism, including chronic inflammation, hormonal disorders, dysregulation of adipokines, and microbial dysbiosis, may be important contributors to cancer development and progression. These contributors play different roles in cancer development and progression at different sites. Lifestyle changes, weight loss medications, and bariatric surgery are key approaches for weight-centered, obesity-related cancer prevention. Treatment of obesity-related inflammation and hormonal or metabolic dysregulation with medications has also shown promise in preventing obesity-related cancers. In this review, we summarize the mechanisms through which obesity affects the risk of cancer at different sites and explore intervention strategies for the prevention of obesity-associated cancers, concluding with unresolved questions and future directions regarding the link between obesity and cancer. The aim is to provide valuable theoretical foundations and insights for the in-depth exploration of the complex relationship between obesity and cancer risk and its clinical applications.

Overweight and obesity significantly increase colorectal cancer risk: a meta-analysis of 66 studies revealing a 25-57% elevation in risk

The incidence of colorectal cancer (CRC) has been steadily rising, and obesity has been identified as a significant risk factor. Numerous studies suggest a strong correlation between excess body weight and increased risk of CRC, but comprehensive quantification through pooled analysis remains limited. This study aims to systematically review and meta-analyze the existing literature to evaluate the association between obesity and CRC risk, considering variations across sex and study designs. A systematic literature search was conducted in PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science to identify randomized controlled trials and human clinical trials from 1992 to 2024. Statistical analysis was performed using the https://metaanalysisonline.com web application using a random effects model to estimate the pooled hazard rates (HR). Forest plots, funnel plots, and Z-score plots were utilized to visualize results. We identified 52 clinical trials and 14 case-control studies, encompassing a total of 83,251,050 and 236,877 subjects, respectively. The pooled analysis indicated that obesity significantly increased the prevalence of CRC (HR = 1.36, 95% CI = 1.24-1.48, p < 0.01). This effect was consistent across sexes, with HRs of 1.57 (95% CI = 1.38-1.78, p = 0.01) for males and 1.25 (95% CI = 1.14-1.38, p < 0.01) for females. Case-control studies specifically showed an effect, but with marginal significance only (HR = 1.27, 95% CI = 0.98-1.65, p = 0.07). The Z-score plot indicated the need for additional analysis in the case-control group. A significant heterogeneity was observed across studies in all four settings. This meta-analysis provides robust evidence that obesity is a significant risk factor for colorectal cancer, with an overall hazard rate indicating a 36% increased risk. The effect is pronounced across both sexes, with males showing a slightly higher risk compared to females. Although case-control studies showed a weaker association, the overall trend supports the link between obesity and CRC. These results underscore the importance of public health interventions aimed at reducing obesity to potentially lower the risk of colorectal cancer.

The Effect of Dietary Fiber on Hyperkalemia in Maintenance Hemodialysis Patients: A Cross-Sectional Study

OBJECTIVE

To explore the relationship between dietary fiber (DF) intake and hyperkalemia in maintenance hemodialysis (MHD) patients.

METHODS

A total of 110 MHD patients were included, including 67 males and 43 females. Patients were divided into normal serum potassium group (N) and a hyperkalemia group (H) according to the serum potassium level before dialysis. The daily diet was recorded by the 3-day dietary recording method. The daily dietary nutrient intake of patients was analyzed. Logistic regression was used to analyze the relationship between hyperkalemia and DF intake. A receiver operating characteristic curve was used to analyze the cutoff value of DF intake to prevent hyperkalemia.

RESULTS

Of the 110 patients, 38 had hyperkalemia (serum potassium >5.5 mmol/L) before dialysis. There was no difference in sex, residual kidney function, body mass index, energy intake, fat intake, protein intake, calcium intake, sodium intake, phosphorus intake or the administration history of potassium-lowering drugs between the 2 groups (P > .05). Compared with the H group, patients in the N group had higher carbohydrate intake (315 ± 76 g/d vs. 279 ± 66 g/d, P = .016), dietary fiber intake (19 ± 5 g/d vs. 12 ± 8 g/d, P < .0001), and potassium intake (1,698 ± 392 mg/d vs. 1,533 ± 413 mg/d, P = .041), and more patients in group N used renin-angiotensin-aldosterone system inhibitors (52.78% vs. 23.68%, P = .003). However, the number of patients with constipation in group N was less than that in group H (20.83% vs. 42.11%, P = .018). Logistic regression analysis showed that DF intake was an independent protective factor for hyperkalemia [P < .0001, odds ratio = 0.766 (95% confidence intervals: 0.675-0.870)]. Receiver operating characteristic analysis showed that daily intake of DF greater than 15.33 g may be helpful to prevent hyperkalemia.

CONCLUSION

Insufficient dietary nutrient intake is prevalent in MHD patients, especially DF intake, which may be associated with hyperkalemia. Clinically, attention should be given to the dietary balance of MHD patients, especially DF intake.

Melanoma and microbiota: Current understanding and future directions

Over the last decade, the composition of the gut microbiota has been found to correlate with the outcomes of cancer patients treated with immunotherapy. Accumulating evidence points to the various mechanisms by which intestinal bacteria act on distal tumors and how to harness this complex ecosystem to circumvent primary resistance to immune checkpoint inhibitors. Here, we review the state of the microbiota field in the context of melanoma, the recent breakthroughs in defining microbial modes of action, and how to modulate the microbiota to enhance response to cancer immunotherapy. The host-microbe interaction may be deciphered by the use of "omics" technologies, and will guide patient stratification and the development of microbiota-centered interventions. Efforts needed to advance the field and current gaps of knowledge are also discussed.