Downregulated exosome-associated gene FGF9 as a novel diagnostic and prognostic target for ovarian cancer and its underlying roles in immune regulation

Hsa_circ_0125356 promotes gemcitabine resistance by modulating WNT canonical and non-canonical pathways via miR-582-5p/FGF9 axis in non-small cell lung cancer

BACKGROUND

Non-small cell lung cancer (NSCLC) is the leading cause of cancer morbidity and mortality worldwide. The prognosis of patients has been significantly improved by chemotherapy, but acquired drug resistance remains a major obstacle to NSCLC treatment. Circular RNAs (circRNAs), which act as miRNA or protein sponges, are critically associated with the development and chemotherapy resistance of NSCLC.

METHODS

CircRNA sequencing was performed to analyze the differential expression of circRNAs between A549 and A549-GR cells. Chromogenic in situ hybridization (CISH) and immunohistochemistry (IHC) technologies were used to detect the expression of hsa_circ_0125356, miR-582-5p,and FGF9 in NSCLC tissues and para-carcinoma tissues. Fluorescence in situ hybridization (FISH), dual-luciferase reporter assays and RNA immunoprecipitation (RIP) were conducted to evaluate the expression and regulation of hsa_circ_0125356, miR-582-5p, and FGF9. Furthermore, the regulation of hsa_circ_0125356/miR-582-5p/FGF9 on gemcitabine sensitivity was confirmed by TUNEL, Transwell, EdU, CCK8 and immunohistochemistry.

RESULTS

We identified a novel hsa_circ_0125356 as a therapeutic target against gemcitabine resistance. Hsa_circ_0125356 was significantly elevated in clinical samples of patients with NSCLC. Moreover, hsa_circ_0125356 overexpression promoted gemcitabine resistance to NSCLC by upregulating FGF9 via sponging miR-582-5p in vivo and in vitro. Notably, WNT canonical (ERK/GSK3β/β-catenin) and non-canonical (Daam1/RhoA/ROCK2) signaling pathways were activated due to hsa_circ_0125356 acting as an endogenous miR-582-5p sponge to regulate the expression of FGF9, and thereby enhancing gemcitabine resistance via promoting DNA damage repair and inhibition of apoptosis. The results were further confirmed by two small molecule antagonists, WAY 316606 and XAV-939,which could inhibit the activation of WNT signaling pathway induced by hsa_circ_0125356.

CONCLUSION

We first demonstrated that hsa_circ_0125356 was significantly upregulated and served as a biomarker for gemcitabine resistance in NSCLC by sponging miR-582-5p/FGF9 axis to regulate the WNT canonical and non-canonical signaling pathways, which provided a new direction for identification of therapeutic targets for the treatment of gemcitabine resistance of NSCLC.

Prognostic value and microenvironmental crosstalk of exosome-related signatures in human epidermal growth factor receptor 2 positive breast cancer

This study aimed to determine the prognostic value and microenvironmental crosstalk of exosome-related signatures in human epidermal growth factor receptor 2 positive breast cancer (HER2+ BC). Transcriptome sequencing and clinicopathological data were downloaded from the Cancer Genome Atlas. The 10X single cell sequencing dataset was downloaded from the National Center for Biotechnology Information Gene Expression Omnibus. Exosomes-Related Genes were extracted from the ExoCarta and Gene Set Enrichment Analysis databases. FGF9, SF3B4, and EPCAM were found and deemed the most accurate predictive signatures. Patients with HER2+ BC were subtyped into three groupings by exosome prognostic gene (EPGs). The expression of SF3B4 was positively linked with the infiltration of macrophages, neutrophils, and CD4+ T cells. The expression characteristics of EPGs were associated with the biological process of "response to xenobiotic stimuli." Interactions were relatively high between malignant epithelial cells and fibroblasts, endothelial cells, monocytes, and macrophages. Malignant epithelial cells interact more with fibroblasts and endothelial cells. The migration inhibitory factor pathway was the primary outgoing signaling pattern, while the C-C motif chemokine ligand pathway was the primary incoming signaling pattern for communication between malignant epithelial cells and macrophages. This study described the role of exosome signatures in the prognosis and microenvironment of HER2+ BC and provided a basis for future research.

Application of exosomes in tumor immunity: recent progresses

Exosomes are small extracellular vesicles secreted by cells, ranging in size from 30 to 150 nm. They contain proteins, nucleic acids, lipids, and other bioactive molecules, which play a crucial role in intercellular communication and material transfer. In tumor immunity, exosomes present various functions while the following two are of great importance: regulating the immune response and serving as delivery carriers. This review starts with the introduction of the formation, compositions, functions, isolation, characterization, and applications of exosomes, and subsequently discusses the current status of exosomes in tumor immunotherapy, and the recent applications of exosome-based tumor immunity regulation and antitumor drug delivery. Finally, current challenge and future prospects are proposed and hope to demonstrate inspiration for targeted readers in the field.

Exosomal circRNAs in gastrointestinal cancer: Role in occurrence, development, diagnosis and clinical application (Review)

Gastrointestinal cancer is frequently detected at an advanced stage and has an undesirable prognosis due to the absence of efficient and precise biomarkers and therapeutic targets. Exosomes are small, living‑cell‑derived vesicles that serve a critical role in facilitating intercellular communication by transporting molecules from donor cells to receiver cells. circular RNAs (circRNAs) are mis‑expressed in a variety of diseases, including gastrointestinal cancer, and are promising as diagnostic biomarkers and tumor therapeutic targets for gastrointestinal cancer. The main features of exosomes and circRNAs are discussed in the present review, along with research on the biological function of exosomal circRNAs in the development and progression of gastrointestinal cancer. It also assesses the advantages and disadvantages of implementing these findings in clinical applications.

Transforming native exosomes to engineered drug vehicles: A smart solution to modern cancer theranostics

Exosomes have been the hidden treasure of the cell in terms of cellular interactions, transportation and therapy. The native exosomes (NEx) secreted by the parent cells hold promising aspects in cancer diagnosis and therapy. NEx has low immunogenicity, high biocompatibility, low toxicity and high stability which enables them to be an ideal prognostic biomarker in cancer diagnosis. However, due to heterogeneity, NEx lacks specificity and accuracy to be used as therapeutic drug delivery vehicle in cancer therapy. Transforming these NEx with their innate structure and multiple receptors to engineered exosomes (EEx) can provide better opportunities in the field of cancer theranostics. The surface of the NEx exhibits numeric receptors which can be modified to pave the direction of its therapeutic drug delivery in cancer therapy. Through surface membrane, EEx can be modified with increased drug loading potentiality and higher target specificity to act as a therapeutic nanocarrier for drug delivery. This review provides insights into promising aspects of NEx as a prognostic biomarker and drug delivery tool along with its need for the transformation to EEx in cancer theranostics. We have also highlighted different methods associated with NEx transformations, their nano-bio interaction with recipient cells and major challenges of EEx for clinical application in cancer theranostics.

Latest progress in low-intensity pulsed ultrasound for studying exosomes derived from stem/progenitor cells

Stem cells have self-renewal, replication, and multidirectional differentiation potential, while progenitor cells are undifferentiated, pluripotent or specialized stem cells. Stem/progenitor cells secrete various factors, such as cytokines, exosomes, non-coding RNAs, and proteins, and have a wide range of applications in regenerative medicine. However, therapies based on stem cells and their secreted exosomes present limitations, such as insufficient source materials, mature differentiation, and low transplantation success rates, and methods addressing these problems are urgently required. Ultrasound is gaining increasing attention as an emerging technology. Low-intensity pulsed ultrasound (LIPUS) has mechanical, thermal, and cavitation effects and produces vibrational stimuli that can lead to a series of biochemical changes in organs, tissues, and cells, such as the release of extracellular bodies, cytokines, and other signals. These changes can alter the cellular microenvironment and affect biological behaviors, such as cell differentiation and proliferation. Here, we discuss the effects of LIPUS on the biological functions of stem/progenitor cells, exosomes, and non-coding RNAs, alterations involved in related pathways, various emerging applications, and future perspectives. We review the roles and mechanisms of LIPUS in stem/progenitor cells and exosomes with the aim of providing a deeper understanding of LIPUS and promoting research and development in this field.

Analysis of the genomic landscape of primary central nervous system lymphoma using whole-genome sequencing in Chinese patients

Primary central nervous system lymphoma (PCNSL) is an uncommon non-Hodgkin's lymphoma with poor prognosis. This study aimed to depict the genetic landscape of Chinese PCNSLs. Whole-genome sequencing was performed on 68 newly diagnosed Chinese PCNSL samples, whose genomic characteristics and clinicopathologic features were also analyzed. Structural variations were identified in all patients with a mean of 349, which did not significantly influence prognosis. Copy loss occurred in all samples, while gains were detected in 77.9% of the samples. The high level of copy number variations was significantly associated with poor progression-free survival (PFS) and overall survival (OS). A total of 263 genes mutated in coding regions were identified, including 6 newly discovered genes (ROBO2, KMT2C, CXCR4, MYOM2, BCLAF1, and NRXN3) detected in ⩾ 10% of the cases. CD79B mutation was significantly associated with lower PFS, TMSB4X mutation and high expression of TMSB4X protein was associated with lower OS. A prognostic risk scoring system was also established for PCNSL, which included Karnofsky performance status and six mutated genes (BRD4, EBF1, BTG1, CCND3, STAG2, and TMSB4X). Collectively, this study comprehensively reveals the genomic landscape of newly diagnosed Chinese PCNSLs, thereby enriching the present understanding of the genetic mechanisms of PCNSL.

Application of Extracellular Vesicles in Gynecologic Cancer Treatment

Ovarian, cervical, and endometrial cancer are the three most common gynecological malignancies that seriously threaten women's health. With the development of molecular biology technology, immunotherapy and targeted therapy for gynecologic tumors are being carried out in clinical treatment. Extracellular vesicles are nanosized; they exist in various body fluids and play an essential role in intercellular communication and in the regulation of various biological process. Several studies have shown that extracellular vesicles are important targets in gynecologic cancer treatment as they promote tumor growth, progression, angiogenesis, metastasis, chemoresistance, and immune system escape. This article reviews the progress of research into extracellular vesicles in common gynecologic tumors and discusses the role of extracellular vesicles in gynecologic tumor treatment.

Identification of Downregulated Exosome-Associated Gene ENPP1 as a Novel Lipid Metabolism and Immune-Associated Biomarker for Hepatocellular Carcinoma

Exosome plays an important role in the occurrence and development of tumors, such as hepatocellular carcinoma (LIHC). However, the functions and mechanisms of exosome-associated molecules in LIHC are still underexplored. Here, we investigated the role of the exosome-related gene ENPP1 in LIHC. Comprehensive bioinformatics from multiple databases revealed that ENPP1 was significantly downregulated in LIHC tissues. The patients with downregulated ENPP1 displayed a poor prognosis. Immunohistochemistry (IHC) was used to further confirm the downregulated ENPP1 in LIHC tissues. In addition, the coexpression network of ENPP1 was also explored to understand its roles in the underlying signaling pathways, including fatty acid degradation and the PPAR signaling pathway. Simultaneously, GSEA analysis indicated the potential roles of ENPP1 in the lipid metabolism-associated signaling pathways in the pathogenesis of LIHC, including fatty acid metabolism, fatty acid synthesis, and so on. Finally, immunological analysis indicated that ENPP1 might also be involved in multiple immune-related features, including immunoinhibitors, immunostimulators, and chemokines. Taken together, these findings could enhance our understanding of ENPP1 in LIHC pathogenesis and immune response and provide a new target for ENPP1-related immunotherapy in clinical treatment.

A prognostic exosome-related LncRNA risk model correlates with the immune microenvironment in liver cancer

Background: Emerging studies have shown the important roles of long noncoding RNAs (lncRNAs) in the occurrence and development of liver cancer. However, the exosome-related lncRNA signature in liver cancer remains to be clarified. Methods: We obtained 371 tumor specimens and 50 normal tissues from the TCGA database. These samples were randomly divided into the training queue and verification queue. The exosome-related lncRNA risk model was verified by correlation analysis, Lasso regression analysis, and Cox regression analysis. The differences in the immune microenvironment in the two risk groups were obtained by analyzing the infiltration of different immune cells. Results: Five exosome-related lncRNAs associated (MKLN1-AS, TMCC1-AS1, AL031985.3, LINC01138, AC099850.3) with a poor prognosis were identified and used to construct the signature. Receiver operating curve (ROC) and survival curves were used to confirm the predictive ability of this signature. Based on multivariate regression analysis in the training cohort (HR: 3.033, 95% CI: 1.762-5.220) and validation cohort (HR: 1.998, 95% CI: 1.065-3.751), the risk score was found to be an independent risk factor for patient prognosis. Subsequently, a nomogram was constructed to predict the 1-, 3-, 5-years survival rates of liver cancer patients. Moreover, this signature was also related to overexpressed immune checkpoints (PD-1, B7-H3, VSIR, PD-L1, LAG3, TIGIT and CTLA4). Conclusion: Our study showed that exosome-related lncRNAs and the corresponding nomogram could be used as a better index to predict the outcome and immune regulation of liver cancer patients. This signature might provide a new idea for the immunotherapy of liver cancer in the future.