The biogenesis and secretion of exosomes and multivesicular bodies (MVBs): Intercellular shuttles and implications in human diseases.

Exosomes carry and transmit signaling molecules used for intercellular communication. The generation and secretion of exosomes is a multistep interlocking process that allows simultaneous control of multiple regulatory sites. Protein molecules, mainly RAB GTPases, cytoskeletal proteins and soluble N-ethylmaleimide-sensitive fusion attachment protein receptor (SNARE), are specifically regulated in response to pathological conditions such as altered cellular microenvironment, stimulation by pathogenic factors, or gene mutation. This interferes with the smooth functioning of endocytosis, translocation, degradation, docking and fusion processes, leading to changes in the secretion of exosomes. Large numbers of secreted exosomes are disseminated by the flow of body fluids and absorbed by the recipient cells. By transmitting characteristic functional proteins and genetic information produced under disease conditions, exosomes can change the physiological state of the recipient cells and their microenvironment. The microenvironment, in turn, affects the occurrence and development of disease. Therefore, this review will discuss the mechanism by which exosome secretion is regulated in cells following the formation of mature secretory multivesicular bodies (MVBs). The overall aim is to find ways to eliminate disease-derived exosomes at their source, thereby providing an important new basis for the clinical treatment of disease.

Serum galectin-3 as a biomarker for screening, early diagnosis, prognosis and therapeutic effect evaluation of pancreatic cancer.

Galectin-3 plays an important role in cell-cell adhesion, macrophage activation, angiogenesis, metastasis and apoptosis and is overexpressed in pancreatic cancer. We explored the importance of galectin-3 in the screening, early diagnosis, prognosis and therapeutic effect evaluation of pancreatic cancer. A time-resolved fluorescence immunoassay was performed to detect serum galectin-3 level. Serum samples were collected from healthy controls and patients with pancreatic cancer before and after different treatments, and the relationships between galectin-3 level and clinical parameters were analysed. Among the healthy controls, one individual with an abnormally high concentration of galectin-3 (9.85 µg/L) was diagnosed with pancreatic cancer. Compared to the pre-operative level, galectin-3 concentration significantly decreased in patients with radical excision 1 month after surgery (P < .05), but showed no obvious change in patients who underwent palliative resection. Additionally, among patients with radical excision, carcinoma recurrence rate was significantly higher in those with increased or unchanged galectin-3 level. Retrospective analysis revealed the extraordinarily high value and high specificity of galectin-3 for predicting 3-year survival (P < .001). Thus, galectin-3 may serve as a potential biomarker for the screening and early diagnosis of pancreatic cancer and as an independent prognostic indicator in patients with pancreatic cancer.

The AKR1B1 inhibitor epalrestat suppresses the progression of cervical cancer.

Cervical cancer is the leading cause of cancer-related death among women worldwide. Identifying an effective treatment with fewer side effects is imperative, because all of the current treatments have unique disadvantages. Aldo-keto reductase family 1 member B1 (AKR1B1) is highly expressed in various cancers and is associated with tumor development, but has not been studied in cervical cancer. In the current study, we used CRISPR/Cas9 technology to establish a stable HeLa cell line with AKR1B1 knockout. In vitro, AKR1B1 knockout inhibited the proliferation, migration and invasion of HeLa cells, providing evidence that AKR1B1 is an innovative therapeutic target. Notably, the clinically used epalrestat, an inhibitor of aldose reductases, including AKR1B1, had the same effect as AKR1B1 knockout on HeLa cells. This result suggests that epalrestat could be used in the clinical treatment of cervical cancer, a prospect that undoubtedly requires further research. Moreover, aiming to determine the underlying regulatory mechanism of AKR1B1, we screened a series of differentially regulated genes (DEGs) by RNA sequencing and verified selected DEGs by quantitative RT-PCR. In addition, gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of the DEGs revealed a correlation between AKR1B1 and cancer. In summary, epalrestat inhibits the progression of cervical cancer by inhibiting AKR1B1, and thus may be a new drug for the clinical treatment of cervical cancer.