Associations of body mass index, weight change, physical activity and sedentary behavior with endometrial cancer risk among Japanese women: The Japan Collaborative Cohort Study

Role of body mass index and weight change in the risk of cancer: A systematic review and meta-analysis of 66 cohort studies

Background

This study was designed to evaluate the effects of body mass index (BMI) and weight change on the risk of developing cancer overall and cancer at different sites.

Methods

We searched PubMed and other databases up to July 2023 using the keywords related to 'risk', 'cancer', 'weight', 'overweight', and 'obesity'. We identified eligible studies, and the inclusion criteria encompassed cohort studies in English that focused on cancer diagnosis and included BMI or weight change as an exposure factor. Multiple authors performed data extraction and quality assessment, and statistical analyses were carried out using RevMan and R software. We used random- or fixed-effects models to calculate the pooled relative risk (RR) or hazard ratio along with 95% confidence intervals (CIs). We used the Newcastle-Ottawa Scale to assess study quality.

Results

Analysis included 66 cohort studies. Compared to underweight or normal weight, overweight or obesity was associated with an increased risk of endometrial cancer, kidney cancer, and liver cancer but a decreased risk of prostate cancer and lung cancer. Being underweight was associated with an increased risk of gastric cancer and lung cancer but not that of postmenopausal breast cancer or female reproductive cancer. In addition, weight loss of more than five kg was protective against overall cancer risk.

Conclusions

Overweight and obesity increase the risk of most cancers, and weight loss of >5 kg reduces overall cancer risk. These findings provide insights for cancer prevention and help to elucidate the mechanisms underlying cancer development.

Registration

Reviewregistry1786.

The role of exercise in obesity-related cancers: Current evidence and biological mechanisms

Cancer ranks among the five leading causes of death in almost all countries and has important repercussions for individual and public health, the healthcare system, and society in general. Obesity increases the incidence of many types of cancer, but growing evidence suggests that physical activity may decrease risk for developing a variety of obesity-related cancer types, and, in some cases, may improve cancer prognosis and mortality rates. This review summarizes recent evidence on the effect of physical activity on obesity-related cancer prevention and survival. For some cancers, including breast, colorectal, and endometrial cancer, there is strong evidence for a preventative effect of exercise, but for many others, including gallbladder and kidney cancer, and multiple myeloma, evidence is inconsistent or largely lacking. Though many potential mechanisms have been proposed to explain the onco-protective effect of exercise, including improved insulin sensitivity, alterations in sex hormone availability, improved immune function and inflammation, myokine secretion, and modulation of intracellular signaling at the level of AMP kinase, the exact mechanism(s) of action within each cancer subtype remains poorly defined. Overall, a deeper understanding of how exercise can help against cancer and of the exercise parameters that can be altered to optimize exercise prescription is necessary and should be the subject of future investigation.

Does endometriosis increase the risks of endometrial hyperplasia and endometrial cancer?

OBJECTIVE

The risk of developing endometrial hyperplasia after diagnosis of endometriosis has not been determined. Moreover, the risk of endometrial cancer associated with endometriosis is unclear. This nationwide population-based study investigated the associations of endometrial hyperplasia and endometrial cancer with endometriosis, after adjusting for covariates.

METHODS

This population-based observational study analyzed data from the Korean National Health Insurance (NHI) database, including 147,869 women who were diagnosed with endometriosis from 2002 to 2017, with each patient matched to 20 control women without endometriosis. Cox proportional hazard regression analyses were performed to estimate the hazard ratios (HRs) of endometrial hyperplasia, endometrial cancer, and mortality from endometrial cancer.

RESULTS

Among three million women in this population, 16,377 women were diagnosed with endometrial hyperplasia, and 1795 women were diagnosed with endometrial cancer over 19,931,794 person-years of follow-up. Women with endometriosis were at significantly higher risks of endometrial hyperplasia (adjusted hazard ratio [aHR] 1.85, 95% confidence interval [CI] 1.75-1.95), and endometrial cancer (aHR 1.35, 95% CI 1.12-1.63) were compared with control women after adjustment for covariates. A diagnosis of endometriosis did not affect survival in patients with endometrial cancer.

CONCLUSION

The risks of endometrial hyperplasia and endometrial cancer were found to be significantly higher in women with than without endometriosis. The presence of endometriosis did not affect overall survival in women with endometrial cancer. Additional long-term prospective studies with adequate control of confounders are needed.

Anti-tumor effect of Wasabi component, 6-(methylsulfinyl) hexyl isothiocyanate, against endometrial carcinoma cells

PURPOSE

Wasabi is a traditional plant seasoning with an anti-septic function. Recent studies revealed several functions of Wasabi, such as anti-inflammation; however, the anti-tumor effect against endometrial carcinoma (EMC) cells has not been examined. In the present study, we investigated the anti-tumor effect of 6-(methylsulfinyl) hexyl isothiocyanate (6-MITC), a major chemical compound of Wasabi, against various EMC cell lines in vitro and in vivo.

METHODS

The effect of 6-MITC on cell viability was measured by the WST-1 assay in EMC and HUVEC cells. The impact of 6-MITC oral administration in nude mice was measured to assess the growth of the EMC xenograft and natural killer (NK) cell activity in the spleen.

RESULTS

The addition of 6-MITC suppressed the proliferation of EMC cells (Ishikawa, HEC265, HEC108, KLE, and HEC1B) dose-dependently, but not HUVEC cells. 6-MITC (5 µM) enhanced the cisplatin sensitivity of EMC cells. 6-MITC induced apoptosis in a dose-dependent fashion in EMC cells other than HEC1B cells and was associated with increased expression of cleaved-caspase3 and decreased expression of BCL2. Oral administration of 6-MITC (2 and 4 µmol/kg) to Ishikawa and HEC1B xenografting mice resulted in a reduced tumor volume compared with the control (P < 0.05, 4 µmol/kg). Immunohistochemical staining of resected tumors revealed increased expression of Ki-67 and reduced cleaved-caspase3. Furthermore, 6-MITC treatment enhanced NK cell activity, especially when administered before tumor xenografting.

CONCLUSION

These results indicate that 6-MITC has a marked anti-tumor effect against EMC cells and a novel effect to enhance NK cell activity. These effects suggest the therapeutic potential of 6-MITC.

The interplay of sex steroid hormones and microRNAs in endometrial cancer: current understanding and future directions

Introduction

Endometrial cancer is a hormone-dependent malignancy, and sex steroid hormones play a crucial role in its pathogenesis. Recent studies have demonstrated that microRNAs (miRNAs) can regulate the expression of sex steroid hormone receptors and modulate hormone signaling pathways. Our aim is to provide an overview of the current understanding of the role of miRNAs in endometrial cancer regulated by sex steroid hormone pathways.

Methods

A thorough literature search was carried out in the PubMed database. The articles published from 2018 to the present were included. Keywords related to miRNAs, endometrial cancer, and sex steroid hormones were used in the search.

Results

Dysregulation of miRNAs has been linked to abnormal sex steroid hormone signaling and the development of endometrial cancer. Various miRNAs have been identified as modulators of estrogen and progesterone receptor expression, and the miRNA expression profile has been shown to be a predictor of response to hormone therapy. Additionally, specific miRNAs have been implicated in the regulation of genes involved in hormone-related signaling pathways, such as the PI3K/Akt/mTOR and MAPK/ERK pathways.

Conclusion

The regulation of sex steroid hormones by miRNAs is a promising area of research in endometrial cancer. Future studies should focus on elucidating the functional roles of specific miRNAs in sex steroid hormone signaling and identifying novel miRNA targets for hormone therapy in endometrial cancer management.

Sedentary behavior and cancer-an umbrella review and meta-analysis

Several systematic reviews and meta-analyses have summarized the association between sedentary behavior (SB) and cancer. However, the level of evidence and the potential for risk of bias remains unclear. This umbrella review summarized the current data on SB in relation to cancer incidence and mortality, with a particular emphasis on assessing the risk of bias. We searched PubMed, Web of Science and Cochrane Database for systematic reviews and meta-analyses on the association between SB and cancer incidence and mortality. We also searched for recent observational studies not yet included in existing meta-analyses. We re-calculated summary risk estimates for cancer incidence and mortality using random effects models. We included 14 meta-analyses covering 17 different cancer sites from 77 original studies. We found that high SB levels increase the risk for developing ovarian, endometrial, colon, breast, prostate, and rectal cancers, with relative risks of 1.29 (95% confidence interval (CI) = 1.08-1.56), 1.29 (95% CI = 1.16-1.45), 1.25 (95% CI = 1.16-1.33), 1.08 (95% CI = 1.04-1.11), 1.08 (95% CI = 1.00-1.17), and 1.07 (95% CI = 1.01-1.12), respectively. Also, we found an increased risk of cancer mortality of 1.18 (95% CI = 1.09-1.26). Most associations between SB and specific cancer sites were supported by a "suggestive" level of evidence. High levels of SB are associated with increased risk of several types of cancer and increased cancer mortality risk.

Obesity increases endometrial cancer risk in Chinese women with postmenopausal bleeding

OBJECTIVE

We examined the relationship between body mass index (BMI) at referral and subsequent diagnosis of endometrial cancer in a cohort of Chinese women presenting with postmenopausal bleeding, to determine whether BMI of 25 kg/m2 would serve to delineate women at increased risk of endometrial cancer.

METHODS

This cohort included 4,164 Chinese women referred for postmenopausal bleeding from 2002 to 2013. For all women, a medical history was taken, and physical examination, BMI measurement, transvaginal pelvic ultrasonography, and endometrial sampling were performed. Additional investigations were performed as indicated clinically. The presence of risk factors for endometrial cancer and histological diagnoses were compared among groups defined by the standard Asian BMI cut-off values.

RESULTS

Within the cohort, 868 (20.8%) were overweight (BMI 23-24.9 kg/m2) and 1,611 (38.7%) were obese (BMI ≥25 kg/m2), and 162 (3.9%) had endometrial cancer. The prevalence of endometrial cancer correlated with BMI category (P < 0.001). On multivariate analysis, BMI ≥25 kg/m2 was independently associated with 1.57 times risk of endometrial cancer (95% CI 1.13-2.20, P = 0.008) compared with BMI less than 25 kg/m2.

CONCLUSION

When managing postmenopausal bleeding in Chinese women, the Asian BMI standard for obesity at 25 kg/m2 identified 51% of endometrial cancers in this group and denoted a 57% increased risk of endometrial cancer. Thus obesity could be used to triage women presenting with postmenopausal bleeding for prioritized investigations.