Exosomes From Cancer-Associated Mesenchymal Stem Cells Transmit TMBIM6 to Promote the Malignant Behavior of Hepatocellular Carcinoma via Activating PI3K/AKT Pathway

The science of exosomes: Understanding their formation, capture, and role in cellular communication

Extracellular vesicles (EVs) serve as a crucial method for transferring information among cells, which is vital in multicellular organisms. Among these vesicles, exosomes are notable for their small size, ranging from 20 to 150 nm, and their role in cell-to-cell communication. They carry lipids, proteins, and nucleic acids between cells. The creation of exosomes begins with the inward budding of the cell membrane, which then encapsulates various macromolecules as cargo. Once filled, exosomes are released into the extracellular space and taken up by target cells via endocytosis and similar processes. The composition of exosomal cargo varies, encompassing diverse macromolecules with specific functions. Because of their significant roles, exosomes have been isolated from various cell types, including cancer cells, endothelial cells, macrophages, and mesenchymal cells, with the aim of harnessing them for therapeutic applications. Exosomes influence cellular metabolism, and regulate lipid, glucose, and glutamine pathways. Their role in pathogenesis is determined by their cargo, which can manipulate processes such as apoptosis, proliferation, inflammation, migration, and other molecular pathways in recipient cells. Non-coding RNA transcripts, a common type of cargo, play a pivotal role in regulating disease progression. Exosomes are implicated in numerous biological and pathological processes, including inflammation, cancer, cardiovascular diseases, diabetes, wound healing, and ischemic-reperfusion injury. As a result, they hold significant potential in the treatment of both cancerous and non-cancerous conditions.

The anti-hepatocellular carcinoma effect of Aidi injection was related to the synergistic action of cantharidin, formononetin, and isofraxidin through BIRC5, FEN1, and EGFR

ETHNOPHARMACOLOGICAL RELEVANCE

Aidi injection (ADI) is a popular anti-tumor Chinese patent medicine, widely used in clinics for the treatment of hepatocellular carcinoma (HCC) with remarkable therapeutic effects through multiple targets and pathways. However, the scientific evidence of the synergistic role of the complex chemical component system and the potential mechanism for treating diseases are ignored and remain to be elucidated.

AIM OF THE STUDY

This study aimed to elucidate and verify the cooperative association between the potential active ingredient of ADI, which is of significance to enlarge our understanding of its anti-HCC molecular mechanisms.

MATERIALS AND METHODS

Firstly, the anti-HCC effect of ADI was evaluated in various HCC cells and the zebrafish xenograft model. Subsequently, a variety of bioinformatic technologies, including network pharmacology, weighted gene co-expression network analysis (WGCNA), meta-analysis of gene expression profiles, and pathway enrichment analysis were performed to construct the competitive endogenous RNA (ceRNA) network of ADI intervention in HCC and to establish the relationship between the critical targets/pathways and the key corresponding components, which were involved in ADI against HCC in a synergistic way and were validated by molecular biology experiments.

RESULTS

ADI exerted remarkable anti-HCC in vitro cells and in vivo zebrafish model, especially that the Hep 3B2.1-7 cell showed substantial sensibility to ADI. The ceRNA network revealed that the EGFR/PI3K/AKT signaling pathway was identified as the promising pathway. Furthermore, the meta-analysis also demonstrated the critical role of BIRC5 and FEN1 as key targets. Finally, the synergistic effect of ADI was revealed by discovering the inhibitory effect of cantharidin on BIRC5, formononetin on FEN1 and EGFR, as well as isofraxidin on EGFR.

CONCLUSION

Our study unveiled that the incredible protective effect of ADI on HCC resulted from the synergistic inhibition effect of cantharidin, formononetin, and isofraxidin on multiple targets/pathways, including BIRC5, FEN1, and EGFR/PI3K/AKT, respectively, providing a scientific interpretation of ADI against HCC and a typical example of pharmacodynamic evaluation of other proprietary Chinese patent medicine.

The effects of intracellular and exosomal ncRNAs on cancer progression

Altered gene expression as well as mislocalization of a gene's encoded product (proteins or noncoding RNAs (ncRNAs)) can lead to disease and cancer formation. Multiple studies have indicated that exosomes and their contents act as cell-to-cell communicators and play a key role in cancer progression. Moreover, exosomes contain several functional molecules, including ncRNAs. NcRNAs function as master regulators to coordinate cell growth, cell motility and drug resistance. However, intracellular ncRNAs, which can be transferred to recipient cells via exosomes (exosomal ncRNAs), mediate common/distinct downstream molecules, signaling pathways and functions that are less emphasized concepts in cancer development research. In this study, by using exosomes as a model, we comprehensively discuss the current knowledge regarding (1) the functional role of ncRNAs, both their intracellular and exosomal forms, in cancer progression, (2) the possible mechanism of ncRNA incorporation into exosomes and (3) the therapeutic applications and limitations of exosomes based on current knowledge.

Dual impacts of mesenchymal stem cell-derived exosomes on cancer cells: unravelling complex interactions

Mesenchymal stem cells (MSCs) are multipotent, self-renewing stromal cells found in a variety of adult tissues. MSCs possess a remarkable ability to migrate towards tumor sites, known as homing. This homing process is mediated by various factors, including chemokines, growth factors, and extracellular matrix components present in the tumor microenvironment. MSCs release extracellular vesicles known as exosomes (MSC-Exos), which have been suggested to serve a key role in mediating a wide variety of MSC activities. Through cell-cell communication, MSC-Exos have been shown to alter recipient cell phenotype or function and play as a novel cell-free alternative for MSC-based cell therapy. However, MSC recruitment to tumors allows for their interaction with cancer cells and subsequent regulation of tumor behavior. MSC-Exos act as tumor niche modulators via transferring exosomal contents, such as specific proteins or genetic materials, to the nearby cancer cells, leading to either promotion or suppression of tumorigenesis, angiogenesis, and metastasis, depending on the specific microenvironmental cues and recipient cell characteristics. Consequently, there is still a debate about the precise relationship between tumor cells and MSC-Exos, and it is unclear how MSC-Exos impacts tumor cells. Although the dysregulation of miRNAs is caused by the progression of cancer, they also play a direct role in either promoting or inhibiting tumor growth as they act as either oncogenes or tumor suppressors. The utilization of MSC-Exos may prove to be an effective method for restoring miRNA as a means of treating cancer. This review aimed to present the existing understanding of the impact that MSC-Exos could have on cancer. To begin with, we presented a brief explanation of exosomes, MSCs, and MSC-Exos. Following this, we delved into the impact of MSC-Exos on cancer growth, EMT, metastasis, angiogenesis, resistance to chemotherapy and radiotherapy, and modulation of the immune system. Opposing effects of mesenchymal stem cells-derived exosomes on cancer cells.

Exosomes-regulated lipid metabolism in tumorigenesis and cancer progression

Increasing evidence highlights the role of lipid metabolism in tumorigenesis and tumor progression. Targeting the processes of lipid metabolism, including lipogenesis, lipid uptake, fatty acid oxidation, and lipolysis, is an optimal strategy for anti-cancer therapy. Beyond cell-cell membrane surface interaction, exosomes are pivotal factors that transduce intercellular signals in the tumor microenvironment (TME). Most research focuses on the role of lipid metabolism in regulating exosome biogenesis and extracellular matrix (ECM) remodeling. The mechanisms of exosome and ECM-mediated reprogramming of lipid metabolism are currently unclear. We summarize several mechanisms associated with the regulation of lipid metabolism in cancer, including transport of exosomal carriers and membrane receptors, activation of the PI3K pathway, ECM ligand-receptor interactions, and mechanical stimulation. This review aims to highlight the significance of these intercellular factors in TME and to deepen the understanding of the functions of exosomes and ECM in the regulation of lipid metabolism.

STRIP2 motivates non-small cell lung cancer progression by modulating the TMBIM6 stability through IGF2BP3 dependent

BACKGROUND

Striatin interacting protein 2 (STRIP2) is a core component of the striatin-interacting phosphatase and kinase (STRIPAK) complexes, which is involved in tumor initiation and progression via the regulation of cell contractile and metastasis. However, the underlying molecular mechanisms of STRIP2 in non-small cell lung cancer (NSCLC) progression remain largely unknown.

METHODS

The expressions of STRIP2 and IGF2BP3 in human NSCLC specimens and NSCLC cell lines were detected using quantitative RT-PCR, western blotting, and immunohistochemistry (IHC) analyses. The roles and molecular mechanisms of STRIP2 in promoting NSCLC progression were investigated in vitro and in vivo.

RESULTS

Here, we found that STRIP2 expression was significantly elevated in NSCLC tissues and high STRIP2 expression was associated with a poor prognosis. Knockdown of STRIP2 suppressed tumor growth and metastasis in vitro and in vivo, while STRIP2 overexpression obtained the opposite effect. Mechanistically, P300/CBP-mediated H3K27 acetylation activation in the promoter of STRIP2 induced STRIP2 transcription, which interacted with insulin-like growth factor 2 mRNA-binding protein 3 (IGF2BP3) and upregulated IGF2BP3 transcription. In addition, STRIP2-IGF2BP3 axis stimulated m6A modification of TMBIM6 mRNA and enhanced TMBIM6 stability. Consequently, TMBIM6 involved NSCLC cell proliferation, migration and invasion dependent on STRIP2 and IGF2BP3. In NSCLC patients, high co-expression of STRIP2, IGF2BP3 and TMBIM6 was associated with poor outcomes.

CONCLUSIONS

Our findings indicate that STRIP2 interacts with IGF2BP3 to regulate TMBIM6 mRNA stability in an m6A-dependent manner and may represent a potential prognostic biomarker and therapeutic target for NSCLC.

Biological impact and therapeutic perspective of targeting PI3K/Akt signaling in hepatocellular carcinoma: Promises and Challenges

Cancer progression results from activation of various signaling networks. Among these, PI3K/Akt signaling contributes to proliferation, invasion, and inhibition of apoptosis. Hepatocellular carcinoma (HCC) is a primary liver cancer with high incidence rate, especially in regions with high prevalence of viral hepatitis infection. Autoimmune disorders, diabetes mellitus, obesity, alcohol consumption, and inflammation can also lead to initiation and development of HCC. The treatment of HCC depends on the identification of oncogenic factors that lead tumor cells to develop resistance to therapy. The present review article focuses on the role of PI3K/Akt signaling in HCC progression. Activation of PI3K/Akt signaling promotes glucose uptake, favors glycolysis and increases tumor cell proliferation. It inhibits both apoptosis and autophagy while promoting HCC cell survival. PI3K/Akt stimulates epithelial-to-mesenchymal transition (EMT) and increases matrix-metalloproteinase (MMP) expression during HCC metastasis. In addition to increasing colony formation capacity and facilitating the spread of tumor cells, PI3K/Akt signaling stimulates angiogenesis. Therefore, silencing PI3K/Akt signaling prevents aggressive HCC cell behavior. Activation of PI3K/Akt signaling can confer drug resistance, particularly to sorafenib, and decreases the radio-sensitivity of HCC cells. Anti-cancer agents, like phytochemicals and small molecules can suppress PI3K/Akt signaling by limiting HCC progression. Being upregulated in tumor tissues and clinical samples, PI3K/Akt can also be used as a biomarker to predict patients' response to therapy.

Mesenchymal stem cell-derived exosomes as new tools for delivery of miRNAs in the treatment of cancer

Although ongoing medical research is working to find a cure for a variety of cancers, it continues to be one of the major causes of death worldwide. Chemotherapy and immunotherapy, as well as surgical intervention and radiation therapy, are critical components of cancer treatment. Most anti-cancer drugs are given systemically and distribute not just to tumor tissues but also to normal tissues, where they may cause side effects. Furthermore, because anti-cancer drugs have a low delivery efficiency, some tumors do not respond to them. As a result, tumor-targeted drug delivery is critical for improving the safety and efficacy of anti-cancer treatment. Exosomes are microscopic extracellular vesicles that cells produce to communicate with one another. MicroRNA (miRNA), long non-coding RNA (lncRNA), small interfering RNA (siRNA), DNA, protein, and lipids are among the therapeutic cargos found in exosomes. Recently, several studies have focused on miRNAs as a potential therapeutic element for the treatment of cancer. Mesenchymal stem cells (MSC) have been known to have angiogenic, anti-apoptotic, anti-inflammatory and immunomodulatory effects. Exosomes derived from MSCs are gaining popularity as a non-cellular alternative to MSC-based therapy, as this method avoids unwanted lineage differentiation. Therefore more research have focused on transferring miRNAs to mesenchymal stem cells (MSC) and targeting miRNA-loaded exosomes to cancer cells. Here, we initially gave an overview of the characteristics and potentials of MSC as well as the use of MSC-derived exosomes in cancer therapy. Finally, we emphasized the utilization of MSC-derived exosomes for miRNA delivery in the treatment of cancer.