Energy imbalance and cancer: Cause or consequence?

IGFBP-3 promotes cachexia-associated lipid loss by suppressing insulin-like growth factor/insulin signaling

BACKGROUND

Progressive lipid loss of adipose tissue is a major feature of cancer-associated cachexia. In addition to systemic immune/inflammatory effects in response to tumor progression, tumor-secreted cachectic ligands also play essential roles in tumor-induced lipid loss. However, the mechanisms of tumor-adipose tissue interaction in lipid homeostasis are not fully understood.

METHODS

The yki -gut tumors were induced in fruit flies. Lipid metabolic assays were performed to investigate the lipolysis level of different types of insulin-like growth factor binding protein-3 (IGFBP-3) treated cells. Immunoblotting was used to display phenotypes of tumor cells and adipocytes. Quantitative polymerase chain reaction (qPCR) analysis was carried out to examine the gene expression levels such as Acc1 , Acly , and Fasn et al .

RESULTS

In this study, it was revealed that tumor-derived IGFBP-3 was an important ligand directly causing lipid loss in matured adipocytes. IGFBP-3, which is highly expressed in cachectic tumor cells, antagonized insulin/IGF-like signaling (IIS) and impaired the balance between lipolysis and lipogenesis in 3T3-L1 adipocytes. Conditioned medium from cachectic tumor cells, such as Capan-1 and C26 cells, contained excessive IGFBP-3 that potently induced lipolysis in adipocytes. Notably, neutralization of IGFBP-3 by neutralizing antibody in the conditioned medium of cachectic tumor cells significantly alleviated the lipolytic effect and restored lipid storage in adipocytes. Furthermore, cachectic tumor cells were resistant to IGFBP-3 inhibition of IIS, ensuring their escape from IGFBP-3-associated growth suppression. Finally, cachectic tumor-derived ImpL2, the IGFBP-3 homolog, also impaired lipid homeostasis of host cells in an established cancer-cachexia model in Drosophila . Most importantly, IGFBP-3 was highly expressed in cancer tissues in pancreatic and colorectal cancer patients, especially higher in the sera of cachectic cancer patients than non-cachexia cancer patients.

CONCLUSION

Our study demonstrates that tumor-derived IGFBP-3 plays a critical role in cachexia-associated lipid loss and could be a biomarker for diagnosis of cachexia in cancer patients.

Leptin and adiponectin dynamics at patients with rectal neoplasm - Gender differences

Background

Numerous studies associate adipokines with colorectal malignancy, but few data deal with patients suffering exclusively of rectal carcinoma (RC).

Aims

We evaluated leptin and adiponectin levels in RC patients compared to healthy population and their dynamics after surgery.

Material and methods

Serum leptin and adiponectin were evaluated before surgery in 59 RC consecutive patients (38 males and 21 females), and in age and weight matched healthy controls. Measurements were repeated at 24, 72 hours and 7 days after surgery.

Results

Adipokine levels were higher in women. Controls had higher leptin (32.±4.34 vs 9.51±1.73 ng/ml in women and 11±2.66 vs 2.54±0.39 ng/ml in men, p = 0.00048 and 0.0032) and lower adiponectin (9±0.64 vs 11.85±1.02 μg/ml in women and 7.39±0.51 vs 8.5±0.62 μg/ml in men, p = 0.017 and 0.019) than RC patients. Surgery caused an increase of leptin from 5.11±0.8 to 18.7±2.42 ng/ml, p = 6.85 x 10¨⁸, and a decrease of adiponectin from 9.71±0.58 to 7.87±0.47 μg/ml, p = 1.4 x 10¨¹⁰ for all RC patients and returned thereafter to the initial range at 7 days. Adipokines were correlated with body weight (BW). The significance of correlation persisted after surgery only in males, but disappeared in females. Adipokines were not modified by tumor position, presurgical chemoradiotherapy or surgical technique. Women with RC experiencing weight loss had higher adiponectin than women without weight modifications (p<0.05 at all time points).

Conclusions

Adipokine levels of patients with RC differ from the healthy population, possibly reflecting an adaptation to disease. Adipokine modifications after surgery may be related to acute surgical stress. Whether leptin and adiponectin directly interact is not clear. Women have higher adipokine levels, more so after significant weight loss, but the strength of their correlation with BW decreases after surgery. These data suggest gender differences in the adipokine profile of RC patients which may find clinical applications.

The effects of chemotherapy on energy metabolic aspects in cancer patients: A systematic review

BACKGROUND & AIMS

Cancer survival rates have increased significantly creating more awareness for comorbidities affecting the Quality of Life. Chemotherapy may induce serious metabolic alterations. These complications can create an energy imbalance, worsening prognosis. The effect of chemotherapy on energy metabolism remains largely unknown. The purpose of this systematic review is to determine the impact of chemotherapy on energy metabolism, creating more insight in a patients' energy requirements.

METHODS

We identified relevant studies up to May 2nd, 2019 using PubMed and Web of Science. Studies including all types of cancer and stages were selected. Only patients that underwent chemotherapy whether or not followed by surgery or radiotherapy were selected. Maximum follow-up was set at 6 months. Resting energy expenditure (REE), measured by indirect calorimetry (IC) or predicted by the Harris-Benedict equation (HB_Eq), was our primary outcome. Results regarding body composition were considered as secondary outcome parameter.

RESULTS

16 studies were selected, including 267 patients. Overall, a significant decrease in REE [-1.5% to -24.91%] 1-month post-chemotherapy was reported. Two studies on breast cancer conducted a 3 and 6-month follow-up and found an increase in REE of 4.01% and 5.72% (p < .05), revealing a U-shaped curve in the expression of REE. Changes are accompanied by (non)significant variations in body composition (Fatmass (FM) and Fatfree Mass (FFM)). HB_Eq tends to underestimate REE by 4.03%-27.1%.

CONCLUSION

Alterations in REE, accompanied by changes in body composition, are found during and after chemotherapy in all cancer types and stages, revealing a U-shaped curve. Changes in FFM are suggested to induce variations in REE concomitant to catabolic effects of the disease and administered drug. HB_Eq tends to underestimate REE, stressing the need for adequate assessment to meet patients' energy requirements and support dietary needs.

Changes in midlife fitness, body mass index, and smoking influence cancer incidence and mortality: A prospective cohort study in men

Cancer prevention efforts include modification of unhealthy lifestyle, such as smoking cessation and resisting gain in body weight. Although physical activity is inversely related to risk of several cancers, it is poorly studied whether changes in physical activity or fitness influence future cancer risk. Thus, we aimed to investigate whether changes in midlife cardiorespiratory fitness (CRF), body mass index (BMI), and smoking habits influence cancer incidence and mortality. The study cohort includes 1689 initially healthy men, aged 40-59 years. Measurements of CRF, BMI and information on smoking habits were collected in two repeated waves, 7 years apart. Cox regression models estimated associations as hazard rates (HR) with 95% confidence intervals (CI), between midlife changes in the modifiable lifestyle factors and cancer incidence and mortality. The men were followed prospectively for more than 30 years. Compared to CRF loss (>5%), improved CRF (>5%) was associated with lower cancer incidence (HR 0.81, 95% CI 0.67-0.98) and mortality (HR 0.70, 95% CI 0.54-0.92), and maintaining the CRF stable yielded lower cancer incidence (HR 0.76, 95% CI 0.61-0.95). No association was seen for BMI gain, but maintaining the BMI stable was related to lower cancer incidence (HR 0.77, 95% CI 0.60-0.98), compared to BMI loss. Continue smoking was associated with higher cancer incidence and mortality, compared to men who stopped smoking. In particular, this study adds new knowledge about the potential preventive role of CRF in cancer development and emphasizes lifestyle modification as a highly important effort in cancer prevention.

A Mobile System to Improve Quality of Life Via Energy Balance in Breast Cancer Survivors (BENECA mHealth): Prospective Test-Retest Quasiexperimental Feasibility Study

Background

Energy balance is defined as the difference between energy expenditure and energy intake. The current state of knowledge supports the need to better integrate mechanistic approaches through effective studies of energy balance in the cancer population because of an observed significant lack of adherence to healthy lifestyle recommendations. To stimulate changes in breast cancer survivors’ lifestyles based on energy balance, our group developed the BENECA (Energy Balance on Cancer) mHealth app. BENECA has been previously validated as a reliable energy balance monitoring system.

Objective

Based on our previous results, the goal of this study was to investigate the feasibility of BENECA mHealth in an ecological clinical setting with breast cancer survivors, by studying (1) its feasibility and (2) pretest-posttest differences with regard to breast cancer survivor lifestyles, quality of life (QoL), and physical activity (PA) motivation.

Methods

Eighty breast cancer survivors diagnosed with stage I to IIIA and with a body mass index over 25 kg/m2 were enrolled in this prospective test-retest quasi-experimental study. Patients used BENECA mHealth for 8 weeks and were assessed at baseline and the postintervention period. Feasibility main outcomes included percentage of adoption, usage, and attrition; user app quality perception measured with the Mobile App Rating Scale (MARS); satisfaction with the Net Promoter Score (NPS); and barriers and facilitators of its use. Clinical main outcomes included measuring QoL with the European Organization for Research and Treatment of Cancer QoL Questionnaire Core 30 (EORT QLQ-C30), PA assessment with accelerometry, PA motivation measure with a Spanish self-efficacy scale for physical activity (EAF), and body composition with dual-energy x-ray absorptiometry. Statistical tests (using paired-sample t tests) and Kaplan-Meier survival curves were analyzed.

Results

BENECA was considered feasible by the breast cancer survivors in terms of use (76%, 58/76), adoption (69%, 80/116), and satisfaction (positive NPS). The app quality score did not make it one of the best-rated apps (mean 3.71, SD 0.47 points out of 5). BENECA mHealth improved the QoL of participants (global health mean difference [MD] 12.83, 95% CI 8.95-16.71, P<.001), and EAF score (global MD 36.99, 95% CI 25.52-48.46, P<.001), daily moderate-to-vigorous PA (MD 7.38, 95% CI 0.39-14.37, P=.04), and reduced body weight (MD −1.42, 95% CI −1.97 to −0.87, P<.001).

Conclusions

BENECA mHealth can be considered feasible in a real clinical context to promote behavioral changes in the lifestyles of breast cancer survivors, but it needs to be enhanced to improve user satisfaction with use and functionality. This study highlights the importance of the use of mobile apps based on energy balance and how the QoL of breast cancer survivors can be improved via monitoring.

Adipokines, adiposity, and bone marrow adipocytes: Dangerous accomplices in multiple myeloma

Obesity has become a global epidemic influencing the establishment and progression of a wide range of diseases, such as diabetes, cardiovascular disease, and cancer. In 2016, International Agency for Research on Cancer reported that obesity is now associated with 13 different cancers, one of which is multiple myeloma (MM), a destructive cancer of plasma cells that predominantly reside in the bone marrow. Obesity is the accumulation of excess body fat, which causes metabolic, endocrine, immunologic, and inflammatory-like changes. Obesity is usually associated with an increase in visceral and/or subcutaneous fat; however, an additional fat depot that also responds to diet-induced changes is bone marrow adipose tissue (BMAT). There have been several studies over the past few decades that have identified BMAT as a key driver in MM progression. Adipocytes secrete numerous adipokines, such as leptin, adiponectin, resistin, adipsin, and visfatin, which when secreted at normal controlled levels have protective properties. However, in obesity these levels of secretion change, coupled with an increase in adipocyte number and size causing a profound and lasting effect on the bone microenvironment, contributing to MM cell growth, survival, and migration as well as potentially fueling bone destruction. Obesity is a modifiable risk factor making it an attractive option for targeted therapy. This review discusses the link between obesity, monoclonal gammopathy of undetermined significance (a benign condition that precedes MM), and myeloma, and the contribution of key adipokines to disease establishment and progression.