Exosomes are extracellular vesicles secreted by most eukaryotic cells and participate in intercellular communication. The components of exosomes, including proteins, DNA, mRNA, microRNA, long noncoding RNA, circular RNA, etc., which play a crucial role in regulating tumor growth, metastasis, and angiogenesis in the process of cancer development, and can be used as a prognostic marker and/or grading basis for tumor patients. Hereby, we mainly summarized as followed: the role of exosome contents in cancer, focusing on proteins and noncoding RNA; the interaction between exosomes and tumor microenvironment; the mechanisms that epithelial-mesenchymal transition, invasion and migration of tumor affected by exosomes; and tumor suppression strategies based on exosomes. Finally, the application potential of exosomes in clinical tumor diagnosis and therapy is prospected, which providing theoretical supports for using exosomes to serve precise tumor treatment in the clinic.

The regulatory loop between long noncoding RNAs (lncRNAs) and microRNAs has a dynamic role in transcriptional and translational regulation, and is involved in cancer. However, the regulatory circuitry between lncRNAs and microRNAs in tumorigenesis remains elusive. Here we demonstrate that a nuclear lncRNA LINC00336 is upregulated in lung cancer and functions as an oncogene by acting as a competing endogenous RNA (ceRNAs). LINC00336 bound RNA-binding protein ELAVL1 (ELAV-like RNA-binding protein 1) using nucleotides 1901–2107 of LINC00336 and the RRM interaction domain and key amino acids (aa) of ELAVL1 (aa 101–213), inhibiting ferroptosis. Moreover, ELAVL1 increased LINC00336 expression by stabilizing its posttranscriptional level, whereas LSH (lymphoid-specific helicase) increased ELAVL1 expression through the p53 signaling pathway, further supporting the hypothesis that LSH promotes LINC00336 expression. Interestingly, LINC00336 served as an endogenous sponge of microRNA 6852 (MIR6852) to regulate the expression of cystathionine-β-synthase (CBS), a surrogate marker of ferroptosis. Finally, we found that MIR6852 inhibited cell growth by promoting ferroptosis. These data show that the network of lncRNA and ceRNA has an important role in tumorigenesis and ferroptosis.

Long noncoding RNAs (lncRNA) have been associated with various types of cancer; however, the precise role of many lncRNAs in tumorigenesis remains elusive. Here we demonstrate that the cytosolic lncRNA P53RRA is downregulated in cancers and functions as a tumor suppressor by inhibiting cancer progression. Chromatin remodeling proteins LSH and Cfp1 silenced or increased P53RRA expression, respectively. P53RRA bound Ras GTPase-activating protein-binding protein 1 (G3BP1) using nucleotides 1 and 871 of P53RRA and the RRM interaction domain of G3BP1 (aa 177-466). The cytosolic P53RRA-G3BP1 interaction displaced p53 from a G3BP1 complex, resulting in greater p53 retention in the nucleus, which led to cell-cycle arrest, apoptosis, and ferroptosis. P53RRA promoted ferroptosis and apoptosis by affecting transcription of several metabolic genes. Low P53RRA expression significantly correlated with poor survival in patients with breast and lung cancers harboring wild-type p53. These data show that lncRNAs can directly interact with the functional domain of signaling proteins in the cytoplasm, thus regulating p53 modulators to suppress cancer progression. A cytosolic lncRNA functions as a tumor suppressor by activating the p53 pathway. .