March 15, 2021
If one replaces "Tumor" in the above image with "COVID-19" one has a clear clinical picture of COVID, and Long COVID.
It is now clear that patients present markers of tissue wasting at a stage in which tumor is not yet clinically detectable.
A genetically modified mouse (Cre recombinase) was able to have cancer cachexia induced through manipulation of KRAS. The major genetic event in pancreatic ductal adenocarcinoma is the activating point mutation of the KRAS oncogene; the KRAS protein becomes permanently activated, consequently maintaining the cellular processes of proliferation, transformation, invasion and survival. I can find no studies addressing k-Ras in COVID-19. Perhaps this is a marker to be investigated.
Cardiac alterations are typical in cancer patients and ultimately results in heart failure and arrhythmia, which are two of the concurring causes of death during cachexia. Both of these factors have been observed in Long COVID.
Another observation in Cancer Cachexia is low Albumin levels. These are present in COVID and have been considered to be a predictor of outcome. Additional investigation into pathogenesis of COVID with particular focus on Spike Protein signaling may provide additional insight into the processes at work.
Referenced/Related Papers
Modeling Human Cancer-induced Cachexia
https://cell.com/cell-reports/fulltext/S2211-1247(19)30906-4
Cancer cachexia
https://pubmed.ncbi.nlm.nih.gov/3292798/
Understanding cachexia as a cancer metabolism syndrome