Exosomal miR-328 originated from pulmonary adenocarcinoma cells enhances osteoclastogenesis via downregulating Nrp-2 expression

Exosome-capturing scaffold promotes endogenous bone regeneration through neutrophil-derived exosomes by enhancing fast vascularization

Exosomes (Exos), extracellular vesicles of endosomal origin, are a promising therapeutic platform for tissue regeneration. In the current study, an exosome-capturing scaffold (ECS) was designed to attract and anchor exosomes via electrostatic adherence followed by lipophilic interactions. Our findings demonstrate that local enrichment of exosomes in the ECS implanted into critical mandibular defects could significantly accelerate endogenous bone regeneration by enhancing vascularization at the defect site. Notably, neutrophil (PMN)-derived exosomes (PMN-Exos) were identified as the predominant exosome subtype among all captured exosomes. During endogenous bone regeneration, PMN-Exos promoted endogenous vascularization primarily by stimulating the proliferation of endothelial progenitor cells (EPCs), which play a pivotal role in the vasculogenesis of new blood vessels. Mechanistically, vascularization involved PMN-Exo-derived miR455-3p, which promotes EPC proliferation by targeting the Smad4 pathway. In conclusion, this study offers an ECS with broad application prospects for enhancing tissue regeneration by accelerating vascularization. The elucidation of underlying mechanisms paves the way for developing novel strategies to regenerate various tissues and organs.

Exosomal Manf originated from endothelium regulated osteoclast differentiation by down-regulating NF-κB signaling pathway

BACKGROUND

Endothelium-derived exosomes has been reported to enhanced osteogenesis. However, the role of endothelial exosomes on osteoclastgenesis is still unknown.

METHODS

Human umbilical vein endothelial cells (HUVECs) were used to isolate exosomes. PBS or HUVEC-Exos were used to treat RAW 264.7 cells. Then, the preconditioned RAW 264.7 cells were subjected to TRAP staining and RT-qPCR assays. In vivo, we constracted osteoporosis mice model. PBS or HUVEC-Exos were injected through tail vein after ovariectomy surgery. Bone mass was assessed by micro-CT and TRAP staining. Furthermore, we conducted RNA sequencing and found the genes that were differentially expressed.

RESULTS

Osteoclast differentiation was inhibited by endothelium-derived exosomes in this study. Moreover, HUVEC-Exos demonstrated a specific action on bones to promote in vivo bone resorption. Furthermore, exosomal Manf promoted bone resorption via down-regulating NF-κB signaling, and HUVEC-Exos Manf inhibited osteoclast differentiation in vivo.

CONCLUSION

HUVEC-exosomal Manf suppressed osteoclastogenesis via down-regulating NF-κB signaling.

Lung cancer exosomal Gal3BP promotes osteoclastogenesis with potential connotation in osteolytic metastasis

New insights into cellular interactions and key biomolecules involved in lung cancer (LC) bone metastasis could offer remarkable therapeutic benefits. Using a panel of four LC cells, we investigated LC-bone interaction by exposing differentiating osteoclasts (OCs) to LC cells (LC-OC interaction) directly in a co-culture setting or indirectly via treatment with LC secretomes (conditioned media or exosomes). LC-OC interaction facilitated the production of large-sized OCs (nuclei > 10) coupled with extensive bone resorption pits. Proteomic analysis of LC exosomes identified galectin-3-binding protein (Gal3bp) as a potential biomarker which was released primarily by most of LC-derived exosomes. The facilitation of OC differentiation and function by LC-exosomal Gal3bp was supported by the application of recombinant Gal3bp and anti-Gal3bp in OC treatment. Further, our results exhibited a dysregulation of crucial OC markers (TRAF6, p-SAPK/JNK, p-44/42 MAPK, NFAT2 and CD9) during LC-OC interaction that possibly contributed to the facilitation of osteoclastogenesis. Simulation of bone metastasis via intratibial injection of LC cells revealed Gal3bp's possible roles in enhancing OC activation leading to osseous tissue resorption. Overall, this work implicated LC-exosomal Gal3bp in osteolytic metastasis of LC which warrants further studies to assess its potential prognostic and therapeutic relevance.

Bone marrow adipocytes and lung cancer bone metastasis: unraveling the role of adipokines in the tumor microenvironment

Bone is a common site of metastasis for lung cancer. The "seed and soil" hypothesis suggests that the bone marrow microenvironment ("soil") may provide a conducive survival environment for metastasizing tumor cells ("seeds"). The bone marrow microenvironment, comprising a complex array of cells, includes bone marrow adipocytes (BMAs), which constitute about 70% of the adult bone marrow volume and may play a significant role in tumor bone metastasis. BMAs can directly provide energy for tumor cells, promoting their proliferation and migration. Furthermore, BMAs participate in the tumor microenvironment's osteogenesis regulation, osteoclast(OC) regulation, and immune response through the secretion of adipokines, cytokines, and inflammatory factors. However, the precise mechanisms of BMAs in lung cancer bone metastasis remain largely unclear. This review primarily explores the role of BMAs and their secreted adipokines (leptin, adiponectin, Nesfatin-1, Resistin, chemerin, visfatin) in lung cancer bone metastasis, aiming to provide new insights into the mechanisms and clinical treatment of lung cancer bone metastasis.

The Role of Exosome-Derived microRNA on Lung Cancer Metastasis Progression

The high mortality from lung cancer is mainly attributed to the presence of metastases at the time of diagnosis. Despite being the leading cause of lung cancer death, the underlying molecular mechanisms driving metastasis progression are still not fully understood. Recent studies suggest that tumor cell exosomes play a significant role in tumor progression through intercellular communication between tumor cells, the microenvironment, and distant organs. Furthermore, evidence shows that exosomes release biologically active components to distant sites and organs, which direct metastasis by preparing metastatic pre-niche and stimulating tumorigenesis. As a result, identifying the active components of exosome cargo has become a critical area of research in recent years. Among these components are microRNAs, which are associated with tumor progression and metastasis in lung cancer. Although research into exosome-derived microRNA (exosomal miRNAs) is still in its early stages, it holds promise as a potential target for lung cancer therapy. Understanding how exosomal microRNAs promote metastasis will provide evidence for developing new targeted treatments. This review summarizes current research on exosomal miRNAs' role in metastasis progression mechanisms, focusing on lung cancer.

The diagnostic, prognostic role and molecular mechanism of miR-328 in human cancer

MicroRNA are non-coding small RNAs that bind to their target mRNA and cause mRNA degradation or translation inhibition. MiRNA dysregulation is linked to a variety of human cancers and has a role in the genesis and development of cancer pathology. MiR-328 has been reported to be involved in various human cancers. And miR-328 is considered a key regulator in human cancer. It participates in biological processes such as proliferation, apoptosis, invasion, migration, and EMT. The present review will combine the basic and clinical studies to find that miR-328 promotes tumorigenesis and metastasis in human cancer. And we will describe the diagnostic, prognostic, and therapeutic value of miR-328 in various human cancers.