Inhibiting metastasis is the key to the treatment of malignant tumors. During the development of tumors, the microenvironment plays a significant role, and hypoxia is one of its important characteristics. Exosomes, as an important component of the microenvironment, connect tumor cells with the hypoxic microenvironment and mediate information exchange between cells. Tumor cells secrete more exosomes than normal cells, and hypoxia further stimulates their release. Hypoxia-induced tumor-derived exosomes carry stable genetic material and play key regulatory roles in promoting tumor proliferation, establishing a pre-metastasis microenvironment, and accelerating angiogenesis. This article comprehensively reviews the mechanisms by which tumor-derived exosomes regulate tumor proliferation and metastasis in a hypoxic microenvironment, which has potential clinical significance.
ObjectiveTo summarize the relationship between exosomes and the occurrence and development of gastrointestinal cancer.MethodsThrough online database, we collected the literatures about the relationship between exosomes and the development of gastrointestinal cancer at home and abroad, and then made an review.ResultsExosomes secreted by gastrointestinal cancer cells were related to tumorigenesis, tumor cell survival, chemoresistance, and early metastasis. Exosomes could play the role of information transmission, and regulation of cell physiology and pathological process in the development of gastrointestinal cancer through a variety of intercellular binding ways, and affectted the occurrence and development of gastrointestinal cancer via epigenetic regulation and tumor related signal transduction mechanism. They had been proved to be biomarkers, targets, and drug carriers for the treatment of gastrointestinalcancer.ConclusionIt is a new way to explore the molecular mechanism of exosomes in the development of gastrointestinal cancer.
Objective To summarize the role of exosomal proteins in the occurrence, development, and diagnosis and treatment of pancreatic cancer, providing a reference for the exploration of biomarkers and therapeutic targets in this field. MethodA systematic review of recent domestic and international literature on the mechanisms of exosomes and their proteins in pancreatic cancer was conducted. ResultsProteins carried by tumor-derived exosomes, such as galectin-3 binding protein, V-set andimmunoglobulin domain containing 2, Zrt- and Irt-like protein 4, aspartate aminotransferase 1, could effectively regulate the tumor microenvironment and influence the cell behavior, playing an important role in the occurrence, progression, and metastasis of pancreatic cancer. Additionally, exosomal proteins could serve as potential biomarkers for the early diagnosis of pancreatic cancer. For example, exosomal membrane proteins DNAJ heat shock protein family (HSP40) member B11, and glypican 1 were highly expressed in pancreatic cancer tissues, indicating their potential. ConclusionExosomal proteins are expected to become novel biomarkers and intervention targets for the early diagnosis and targeted therapy of pancreatic cancer, providing new ideas for improving the diagnosis and treatment of pancreatic cancer.
ObjectiveTo investigate the effect of adipose-derived stem cell derived exosomes (ADSC-Exos) on angiogenesis after skin flap transplantation in rats.MethodsADSCs were isolated and cultured by enzymatic digestion from voluntary donated adipose tissue of patients undergoing liposuction. The 3rd generation cells were observed under microscopy and identified by flow cytometry and oil red O staining at 14 days after induction of adipogenesis. After cells were identified as ADSCs, ADSC-Exos was extracted by density gradient centrifugation. And the morphology was observed by transmission electron microscopy, the surface marker proteins (CD63, TSG101) were detected by Western blot, and particle size distribution was measured by nanoparticle size tracking analyzer. Twenty male Sprague Dawley rats, weighing 250-300 g, were randomly divided into ADSC-Exos group and PBS group with 10 rats in each group. ADSC-Exos (ADSC-Exos group) and PBS (PBS group) were injected into the proximal, middle, and distal regions of the dorsal free flaps with an area of 9 cm×3 cm along the long axis in the two groups. The survival rate of the flap was measured on the 7th day, and then the flap tissue was harvested. The tissue morphology was observed by HE staining, and mean blood vessel density (MVD) was measured by CD31 immunohistochemical staining.ResultsADSCs were identified by microscopy, flow cytometry, and adipogenic induction culture. ADSC-Exos was a round or elliptical membrane vesicle with clear edge and uniform size. It has high expression of CD63 and TSG101, and its size distribution was 30-200 nm, which was in accordance with the size range of Exos. The distal necrosis of the flaps in the ADSC-Exos group was milder than that in the PBS group. On the 7th day, the survival rate of the flaps in the ADSC-Exos group was 64.2%±11.5%, which was significantly higher than that in the PBS group (31.0%±6.6%; t=7.945, P=0.000); the skin appendages in the middle region of the flap in the ADSC-Exos group were more complete, the edema in the proximal region was lighter and the vasodilation was more extensive. MVD of the ADSC-Exos group was (103.3±27.0) /field, which was significantly higher than that of the PBS group [(45.3±16.2)/field; t=3.190, P=0.011].ConclusionADSC-Exos can improve the blood supply of skin flaps by promoting the formation of neovascularization after skin flap transplantation, thereby improve the survival rate of skin flaps in rats.
ObjectiveTo evaluate the changes in the expression and significance of serum exosomal miRNAs in patients with DeBakey typeⅠacute aortic dissection (AAD). MethodsTwelve male patients with AAD and six healthy male medical examiners from our hospital were retrospectively included in this study. According to the time of chest pain, the AAD patients were divided into an AAD group within 24 h of chest pain onset, aged 47.00±8.79 years and an AAD group within 48 h of chest pain onset, aged 50.17±9.99 years. The healthy males were allocated to a control group, aged 49.17±4.26 years. Serum exosomal miRNAs were isolated, identified and quantified, and then differentially expressed exosomal miRNAs were screened. The bioinformatic analyses such as GO and KEGG were performed on the differentially expressed exosomal miRNAs. ResultsHigh-throughput screening results revealed differential expression of AAD serum exosomal miRNAs. The upregulated miRNAs of AAD groups was hsa-miR-574-5p (P<0.05), and downregulated miRNAs were hsa-miR-223-3p, hsa-miR-146b-5p, hsa-miR-15b-5p, and hsa-miR-155-5p (P<0.05). Further bioinformatic analysis of the above miRNAs revealed that they were mainly enriched in signaling pathways such as transforming growth factor-β, cell cycle and endoplasmic reticulum protein synthesis. ConclusionDifferential expressions of serum exosomal miRNAs in AAD patients may be related to the pathogenesis of AAD, providing new ideas and clues for further exploration of AAD diagnostic markers and pathogenesis.
Objective
To summarize the bioactive substances contained in bacterial extracellular vesicles (EVs) and their mechanisms in mediating bacterial-bacterial and bacterial-host interactions, as well as their mechanisms for use in implant infection-associated clinical guidance.
Methods
A wide range of publications on bacterial-derived EVs were extensively reviewed, analyzed, and summarized.
Results
Both gram-negative bacteria (G– bacteria) and gram-positive bacteria (G+ bacteria) can secrete EVs which contain a variety of bioactive substances, including proteins, lipids, nucleic acids, and virulence factors, and mediate bacterial-bacterial and bacterial-host interactions. EVs play an important role in the pathogenic mechanism of bacteria.
Conclusion
Bioactive substances contained within bacteria-derived EVs play an important role in the pathogenesis of bacterial infectious diseases. In-depth study and understanding of their pathogenic mechanisms can provide new insights which will improve early clinical diagnosis, prevention, and treatment of implant-associated infection. However, at present, research in this area is still in its infancy, and many more in-depth mechanisms need to be further studied.
ObjectiveTo explore the involvement of miR-126 and the role of mammalian target of rapamycin (mTOR)/hypoxia-induced factor 1 α (HIF-1 α) pathway in regulating human umbilical cord mesenchymal stem cells (hUCMSCs) exosomes (Exo) on vascular endothelial growth factor (VEGF)-A levels in high glucose-induced human retinal vascular endothelial cells (HRECs). MethodsThe hREC was cultured in EGM-2-MV endothelial cell culture medium with 30 mmol/L glucose and placed in hypoxic cell incubator by 1% oxygen concentration. The cell model of high glucose and low oxygen was established. After modeling, divided HRECs into Exo group, phosphate buffer saline (PBS) group, PBS+anti-miR126 group, Exo+anti-miR126 group, PBS+anti-mTOR group, and PBS+anti-HIF-1 α group. High-glucose and hypoxia-induced hREC in the PBS and Exo groups were respectively co-cultured with PBS and 100 μg/ml hUCMSC Exo. PBS+anti-mTOR group, PBS+anti-HIF-1 α group: 500 nmol/L mTOR inhibitor ADZ2014, 25 μmol/L HIF-1 α inhibitor YC-1 pretreatment for hREC 12 h, and then co-culture with PBS after High-glucose and hypoxia-induced. PBS+anti-miR126 group, Exo+anti-miR126 group: miR-126 LNA power inhibitor probe was transfected with high glucose, and co-cultured with PBS and hUCMSC Exo 6 h after transfection. Real-time polymerase chain reaction (qPCR) measured miRNA-126 expression levels in PBS, and Exo groups for 0, 8, 16 and 24 h. After 24 hof co-culture, the levels of mTOR and HIF-1 α in the cells of PBS and Exo groups were detected by immunofluorescence, Western blot and qPCR, respectively. Western blot, qPCR detection of VEGF-A expression levels in cells of the PBS+anti-mTOR and PBS+anti-HIF-1 α groups. The expression of VE GF-A, mTOR, and HIF-1 α mRNA was measured in cells of PBS+anti-miR126 group and Exo+anti-miR126 group by qPCR. Comparison between two groups was performed by t-test; one-way ANOVA was used for comparison between multiple groups. ResultsAt 0, 8, 16 and 24 h, the relative mRNA expression of miR-126 gradually increased in the Exo group (F=95.900, P＜0.05). Compared with the PBS group, The mTOR, HIF-1 α protein (t=3.466, 6.804), mRNA in HRECs in the Exo group, VEGF-A mRNA expression (t=8.642, 7.897, 6.099) were all downregulated, the difference was statistically significant (P＜0.05). The relative expression level of VEGF-Aprotein (t=3.337, 7.380) and mRNA (t=8.515, 10.400) was decreased in HRECs of the anti-mTOR+PBS group and anti-HIF-1 α+PBS group, differences were statistically significant (P＜0.05). The relative expression of VEGF-A, mTOR, and HIF-1 α mRNA was significantly increased in the cells of the Exo+anti-miR126 group, the differences were all statistically significant (t=4.664, 6.136, 6.247; P＜0.05). ConclusionsmiR-126 plays a role in regulating the effect of hUCMSCs exosomes on VEGF-A levels in high glucose-induced HRECs via mTOR-HIF-1 α pathway.
ObjectiveTo investigate the effects of adipose-derived stem cell released exosomes (ADSC-Exos) on wound healing in diabetic mice.MethodsThe ADSCs were isolated from the adipose tissue donated by the patients and cultured by enzymatic digestion. The supernatant of the 3rd generation ADSCs was used to extract Exos (ADSC-Exos). The morphology of ADSC-Exos was observed by transmission electron microscopy. The membrane-labeled proteins (Alix and CD63) were detected by Western blot, and the particle size distribution was detected by nanoparticle tracking analyzer. The fibroblasts were isolated from the skin tissue donated by the patients and cultured by enzymatic digestion. The 5th generation fibroblasts were cultured with PKH26-labeled ADSC-Exos, and observed by confocal fluorescence microscopy. The effects of ADSC-Exos on proliferation and migration of fibroblasts were observed with cell counting kit 8 (CCK-8) and scratch method. Twenty-four 8-week-old Balb/c male mice were used to prepare a diabetic model. A full-thickness skin defect of 8 mm in diameter was prepared on the back. And 0.2 mL of ADSC-Exos and PBS were injected into the dermis of the experimental group (n=12) and the control group (n=12), respectively. On the 1st, 4th, 7th, 11th, 16th, and 21st days, the wound healing was observed and the wound healing rate was calculated. On the 7th, 14th, and 21st days, the histology (HE and Masson) and CD31 immunohistochemical staining were performed to observe the wound structure, collagen fibers, and neovascularization.ResultsADSC-Exos were the membranous vesicles with clear edges and uniform size; the particle size was 40-200 nm with an average of 102.1 nm; the membrane-labeled proteins (Alix and CD63) were positive. The composite culture observation showed that ADSC-Exos could enter the fibroblasts and promote the proliferation and migration of fibroblasts. Animal experiments showed that the wound healing of the experimental group was significantly faster than that of the control group, and the wound healing rate was significantly different at each time point (P<0.05). Compared with the control group, the wound healing of the experimental group was better. There were more microvessels in the early healing stage, and more deposited collagen fibers in the late healing stage. There were significant differences in the length of wound on the 7th, 14th, and 21st days, the number of microvessels on the 7th and 14th days, and the rate of deposited collagen fibers on the 14th and 21st days between the two groups (P<0.05).ConclusionADSC-Exos can promote the wound healing in diabetic mice by promoting angiogenesis and proliferation and migration of fibroblasts and collagen synthesis.
Lung cancer is the malignant tumor with the highest incidence and mortality rates worldwide, and its high lethality is primarily due to its subtle early symptoms, with most cases being diagnosed at an advanced stage. Currently, the diagnosis of lung cancer mainly relies on tissue biopsy to obtain pathological evidence, but this method has limitations such as high invasiveness, restricted sampling, and the risk of complications. Therefore, developing safe, effective, and non-invasive strategies for the early screening and diagnosis of lung cancer (stages Ⅰ/Ⅱ) holds significant clinical importance. As a key component of liquid biopsy, exosomes can stably carry a variety of biological molecular information from their cells of origin. Studies have shown that microRNAs, long non-coding RNAs, circular RNAs, and specific proteins abundantly present in exosomes exhibit abnormal expression during the development of lung cancer, demonstrating high diagnostic value. Compared to traditional detection methods, exosome-based detection offers advantages such as non-invasiveness, repeatability, ease of operation, and cost-effectiveness. This article systematically reviews recent research progress on exosomes as liquid biopsy biomarkers for the early diagnosis and screening of lung cancer, focusing on their potential clinical applications, and explores the prospects of exsomes in the early intervention, precise diagnosis, and prognosis improvement for lung cancer.
ObjectiveTo investigate whether exosomes derived from miR-27a-overexpressing human umbilical vein endothelial cells (HUVECs)—exo (miR-27a) can promote bone regeneration and improve glucocorticoids (GC) induced osteonecrosis of femoral head (ONFH) (GC-ONFH).MethodsThe exo (miR-27a) were intended to be constructed and identified by transmission electron microscopy, nanoparticle tracking analysis, Western blot, and real-time fluorescent quantitative PCR (qRT-PCR). qRT-PCR was used to evaluate the effect of exo (miR-27a) in delivering miR-27a to osteoblasts (MC3T3-E1 cells). Alkaline phosphatase staining, alizarin red staining, and qRT-PCR were used to evaluate its effect on MC3T3-E1 cells osteogenesis. Dual-luciferase reporter (DLRTM) assay was used to verify whether miR-27a targeting Dickkopf WNT signaling pathway inhibitor 2 (DKK2) was a potential mechanism, and the mechanism was further verified by qRT-PCR, Western blot, and alizarin red staining in MC3T3-E1 cells. Finally, the protective effect of exo (miR-27a) on ONFH was verified by the GC-ONFH model in Sprague Dawley (SD) rats.ResultsTransmission electron microscopy, nanoparticle tracking analysis, Western blot, and qRT-PCR detection showed that exo (miR-27a) was successfully constructed. exo (miR-27a) could effectively deliver miR-27a to MC3T3-E1 cells and enhance their osteogenic capacity. The detection of DLRTM showed that miR-27a promoted bone formation by directly targeting DDK2. Micro-CT and HE staining results of animal experiments showed that tail vein injection of exo (miR-27a) improved the osteonecrosis of SD rat GC-ONFH model.Conclusionexo (miR-27a) can promote bone regeneration and protect against GC-ONFH to some extent.
