Cachexia occurs in up to 80% of pancreatic ductal adenocarcinoma (PDAC) patients and is characterized by unintentional weight loss and tissue wasting. To understand the metabolic changes that occur in PDAC-associated cachexia, we compared the abundance of plasma fatty acids (FAs), measured by gas chromatography, of subjects with treatment-naïve metastatic PDAC with or without cachexia, defined as a loss of > 2% weight and evidence of sarcopenia (n = 43). The abundance of saturated, monounsaturated, and polyunsaturated FAs was not different between subjects with cachexia and those without. Oleic acid was significantly higher in subjects with cachexia (p = 0.0007) and diabetes (p = 0.015). Lauric (r = 0.592, p = 0.0096) and eicosapentaenoic (r = 0.564, p = 0.015) acids were positively correlated with age in cachexia patients. Subjects with diabetes (p = 0.021) or both diabetes and cachexia (p = 0.092) had low palmitic:oleic acid ratios. Linoleic acid was lower in subjects with diabetes (p = 0.018) and correlated with hemoglobin (r = 0.519, p = 0.033) and albumin (r = 0.577, p = 0.015) in subjects with cachexia. Oleic or linoleic acid may be useful treatment targets or biomarkers of cachexia in patients with metastatic PDAC, particularly those with diabetes.

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Objectives: Chronic pancreatitis (CP) is an inflammatory disease that affects the absorption of nutrients like fats. Molecular signaling in pancreatic cells can be influenced by fatty acids (FAs) and changes in FA abundance could impact CP-associated complications. Here, we investigated FA abundance in CP compared to controls and explored how CP-associated complications and risk factors affect FA abundance. Methods: Blood and clinical parameters were collected from subjects with (n=47) and without CP (n=22). Plasma was analyzed for relative FA abundance using gas chromatography and compared between controls and CP. Changes in FA abundance due to clinical parameters were also assessed in both groups. Results: Decreased relative abundance of polyunsaturated fatty acids (PUFAs) and increased monounsaturated fatty acids (MUFAs) were observed in subjects with CP in a sex-dependent manner. The relative abundance of linoleic acid increased, and oleic acid decreased in CP subjects with exocrine pancreatic dysfunction and a history of substance abuse. Conclusions: Plasma FAs like linoleic acid are dysregulated in CP in a sex-dependent manner. Additionally, risk factors and metabolic dysfunction further dysregulate FA abundance in CP. These results enhance our understanding of CP and highlight potential novel targets and metabolism-related pathways for treating CP.

Cachexia is a multifactorial syndrome characterized by weight loss and tissue wasting, which is associated with reduced quality of life, responsiveness to chemotherapy, and decreased survival. We aim to determine whether changes in plasma fatty acid content in pancreatic ductal adenocarcinoma (PDAC): 1) are predictive of developing cachexia, and 2) whether these changes are influenced by other clinical parameters, like diabetes, that could contribute to malnutrition. Treatment-naïve metastatic PDAC subjects (n=51) were enrolled in NCT01280058 in which plasma samples and clinical data were collected prior to treatment. Subjects were assigned to either weight stable (<5% relative body weight loss, n=26) or “cachectic” (≥5% weight loss, n=25). Plasma fatty acid composition was analyzed via gas chromatography and reported as a percentage of the total identified fatty acids. Oleic (p=0.004) and adrenic acids (p=0.018) were significantly increased in cachectic subjects, regardless of age, sex, or BMI. Docosapentaenoic n-6 acid was more commonly elevated in older cachectic subjects compared to younger subjects (p=0.048). Adrenic acid levels were higher in subjects with cachexia and diabetes compared to subjects without diabetes with cachexia (p=0.0019) or stable weight (p=0.029). Additionally, linoleic acid was lower in subjects with cachexia and diabetes compared to subjects with cachexia and no diabetes (p=0.015) and subjects with stable weight (p=0.017). Area under the receiver operator curves (AUC) showed that oleic acid (AUC=0.726) and adrenic acid (AUC=0.706) are mildly effective at predicting cachexia, and the combination slightly improved the predictive ability (AUC=0.757). Our pilot study identified several plasma fatty acids that are associated with PDAC-associated cachexia, and are influenced by age and diabetes status. Further studies examining how fatty acids contribute to or arise from the development of cachexia may create opportunities for developing effective therapies for cachexia. Citation Format: Kristyn Gumpper, Phil A. Hart, Martha Belury, Olivia Crowe, Rachel M. Cole, Niharika Badi, Alice Hinton, Mitchell L. Ramsey, Anne Noonan, Darwin L. Conwell, Zobeida Cruz-Monserrate. Plasma fatty acid levels in treatment-naïve metastatic pancreatic cancer patients are associated with clinical indicators of cachexia [abstract]. In: Proceedings of the AACR Virtual Special Conference on Pancreatic Cancer; 2020 Sep 29-30. Philadelphia (PA): AACR; Cancer Res 2020;80(22 Suppl):Abstract nr PO-022.