Targeting Fn14 as a therapeutic target for cachexia reprograms the glycolytic pathway in tumour and brain in mice.

Purpose: Cachexia is a complex syndrome characterized by unintentional weight loss, progressive muscle wasting and loss of appetite. Anti-Fn14 antibody (mAb 002) targets the TWEAK receptor (Fn14) in murine models of cancer cachexia and can extend the lifespan of mice by restoring the body weight of mice. Here, we investigated glucose metabolic changes in murine models of cachexia via [¹⁸F]FDG PET imaging, to explore whether Fn14 plays a role in the metabolic changes that occur during cancer cachexia.

Methods: [¹⁸F]FDG PET/MRI imaging was performed in cachexia-inducing tumour models versus models that do not induce cachexia. SUV_average was calculated for all tumours via volume of interest (VOI) analysis of PET/MRI overlay images using PMOD software.

Results: [¹⁸F]FDG PET imaging demonstrated increased tumour and brain uptake in cachectic versus non-cachectic tumour-bearing mice. Therapy with mAb 002 was able to reduce [¹⁸F]FDG uptake in tumours (P < 0.05, n = 3). Fn14 KO tumours did not induce body weight loss and did not show an increase in [¹⁸F]FDG tumour and brain uptake over time. In non-cachectic mice bearing Fn14 KO tumours, [¹⁸F]FDG tumour uptake was significantly lower (P < 0.01) than in cachectic mice bearing Fn14 WT counterparts. As a by-product of glucose metabolism, l-lactate production was also increased in cachexia-inducing tumours expressing Fn14.

Conclusion: Our results demonstrate that Fn14 receptor activation is linked to glucose metabolism of cachexia-inducing tumours.