Non-coding RNAs in exosomes and adipocytes cause fat loss during cancer cachexia

Abstract

Cancer Cachexia (CC) is a disease that changes various metabolisms in human body. Fat metabolism is significantly affected in CC, leading to fat loss. Non-coding RNAs (ncRNAs) in adipocytes and exosomes secreted by tumor play an important role in fat loss. However, there is no related reviews summarizing how ncRNAs contribute to fat loss during CC. This review screens recent articles to summarize how ncRNAs are packaged, transported in exosomes, and play the role in fat loss. Not only does this review summarize the mechanisms, we also point out the research orientations in the future.

Keywords: Cancer cachexia; Exosomes; Fat loss; Non-coding RNAs.

Fig. 1

The changed expression level of exosomal and intracellular lncRNAs leads to fat loss during CC. Exosomal lncRNAs from tumor cells always bind with specific microRNAs as a sponge to weaken their function. lncRNAs changed in adipose tissue can bind with a protein or a mRNA to promote fat loss. Some of these lncRNAs effect the genes related to adipogenic differentiation, while some down-regulate two vital proteins of adipogenesis, PPAR-γ and C/EBPα. An antisense lncRNA can suppress the expression of mRNA and then reduce the level of hormone about lipid metabolism.

Fig. 2

The changed expression level of exosomal and intracellular miRNAs leads to fat loss during CC. The highly expressed exosomal miRNAs enter target cells. The expressions’ change of exsomal miRNAs and intracellular miRNAs lead to regulating adipogenesis and lipolysis, inducing adipose tissue inflammation, promoting beige/brown differentiation, etc. Finally, changes of exsomal miRNAs and intracellular miRNAs expression lead to fat loss during CC.