Diabetes increases mortality in patients with pancreatic and colorectal cancer by promoting cachexia and its associated inflammatory status.

OBJECTIVES: Cancer is considered an emerging diabetes complication, with higher incidence and worse prognosis in patients with diabetes. Cancer is frequently associated with cachexia, a systemic metabolic disease causing wasting. It is currently unclear how diabetes affects the development and progression of cachexia. METHODS: We investigated the interplay between diabetes and cancer cachexia retrospectively in a cohort of 345 patients with colorectal and pancreatic cancer. We recorded body weight, fat mass, muscle mass, clinical serum values, and survival of these patients. Patients were grouped either into diabetic/non-diabetic groups based on previous diagnosis, or into obese/non-obese groups based on body mass index (BMI ≥30 kg/m2 was considered obese). RESULTS: The pre-existence of type 2 diabetes, but not obesity, in patients with cancer led to increased cachexia incidence (80%, compared to 61% without diabetes, p ≤ 0.05), higher weight loss (8.9% vs. 6.0%, p ≤ 0.001), and reduced survival probability (median survival days: 689 vs. 538, Chi square = 4.96, p ≤ 0.05) irrespective of the initial body weight or tumor progression. Patients with diabetes and cancer showed higher serum levels of C-reactive protein (0.919 µg/mL vs. 0.551 µg/mL, p ≤ 0.01) and interleukin 6 (5.98 pg/mL vs. 3.75 pg/mL, p ≤ 0.05) as well as lower serum albumin levels (3.98 g/dL vs. 4.18 g/dL, p ≤ 0.05) than patients with cancer without diabetes. In a sub-analysis of patients with pancreatic cancer, pre-existing diabetes worsened weight loss (9.95% vs. 6.93%, p ≤ 0.01), and increased the duration of hospitalization (24.41 days vs. 15.85 days, p ≤ 0.001). Further, diabetes aggravated clinical manifestations of cachexia, as changes in the aforementioned biomarkers were more pronounced in patients with diabetes and cachexia co-existence, compared to cachectic patients without diabetes (C-reactive protein: 2.300 µg/mL vs. 0.571 µg/mL, p ≤ 0.0001; hemoglobin: 11.24 g/dL vs. 12.52 g/dL, p ≤ 0.05). CONCLUSIONS: We show for the first time that pre-existing diabetes aggravates cachexia development in patients with colorectal and pancreatic cancer. This is important when considering cachexia biomarkers and weight management in patients with co-existing diabetes and cancer.

Association of circulating PLA2G7 levels with cancer cachexia and assessment of darapladib as a therapy.

BACKGROUND: Cancer cachexia (CCx) is a multifactorial wasting disorder characterized by involuntary loss of body weight that affects many cancer patients and implies a poor prognosis, reducing both tolerance to and efficiency of anticancer therapies. Actual challenges in management of CCx remain in the identification of tumour-derived and host-derived mediators involved in systemic inflammation and tissue wasting and in the discovery of biomarkers that would allow for an earlier and personalized care of cancer patients. The aim of this study was to identify new markers of CCx across different species and tumour entities. METHODS: Quantitative secretome analysis was performed to identify specific factors characteristic of cachexia-inducing cancer cell lines. To establish the subsequently identified phospholipase PLA2G7 as a marker of CCx, plasma PLA2G7 activity and/or protein levels were measured in well-established mouse models of CCx and in different cohorts of weight-stable and weight-losing cancer patients with different tumour entities. Genetic PLA2G7 knock-down in tumours and pharmacological treatment using the well-studied PLA2G7 inhibitor darapladib were performed to assess its implication in the pathogenesis of CCx in C26 tumour-bearing mice. RESULTS: High expression and secretion of PLA2G7 were hallmarks of cachexia-inducing cancer cell lines. Circulating PLA2G7 activity was increased in different mouse models of CCx with various tumour entities and was associated with the severity of body wasting. Circulating PLA2G7 levels gradually rose during cachexia development. Genetic PLA2G7 knock-down in C26 tumours only partially reduced plasma PLA2G7 levels, suggesting that the host is also an important contributor. Chronic treatment with darapladib was not sufficient to counteract inflammation and tissue wasting despite a strong inhibition of the circulating PLA2G7 activity. Importantly, PLA2G7 levels were also increased in colorectal and pancreatic cancer patients with CCx. CONCLUSIONS: Overall, our data show that despite no immediate pathogenic role, at least when targeted as a single entity, PLA2G7 is a consistent marker of CCx in both mice and humans. The early increase in circulating PLA2G7 levels in pre-cachectic mice supports future prospective studies to assess its potential as biomarker for cancer patients.