Connection of Cancer Exosomal LncRNAs, Sponging miRNAs, and Exosomal Processing and Their Potential Modulation by Natural Products

SIMPLE SUMMARY: Cancer cells generally release special vesicles (exosomes) showing tumor-promoting effects. Some natural products blocking exosome processing (assembly and secretion) can inhibit cancer progression. Long noncoding RNAs (lncRNAs), enclosed in exosomes, can bind and modulate several microRNAs (miRNAs), and, in turn, miRNAs can regulate their targets, such as exosome processing genes. However, there is a gap in the correlation between exosomal lncRNAs and exosomal processing of natural product treatments. After collecting and organizing literature reports, we introduce bioinformatics for retrieving miRNA targets of lncRNAs and exosomal processing gene targets of miRNAs to fill this gap. Consequently, the function of exosomal lncRNAs of cancer cells in regulating miRNA targets that potentially modulate exosomal processing genes is summarized, particularly for the anticancer effects of natural products. ABSTRACT: Cancerous exosomes contain diverse biomolecules that regulate cancer progression. Modulating exosome biogenesis with clinical drugs has become an effective strategy for cancer therapy. Suppressing exosomal processing (assembly and secretion) may block exosomal function to reduce the proliferation of cancer cells. However, the information on natural products that modulate cancer exosomes lacks systemic organization, particularly for exosomal long noncoding RNAs (lncRNAs). There is a gap in the connection between exosomal lncRNAs and exosomal processing. This review introduces the database (LncTarD) to explore the potential of exosomal lncRNAs and their sponging miRNAs. The names of sponging miRNAs were transferred to the database (miRDB) for the target prediction of exosomal processing genes. Moreover, the impacts of lncRNAs, sponging miRNAs, and exosomal processing on the tumor microenvironment (TME) and natural-product-modulating anticancer effects were then retrieved and organized. This review sheds light on the functions of exosomal lncRNAs, sponging miRNAs, and exosomal processing in anticancer processes. It also provides future directions for the application of natural products when regulating cancerous exosomal lncRNAs.