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Neuroblastoma (NB) is a challenging pediatric extracranial solid tumor characterized by a poor prognosis and resistance to chemotherapy. Identifying targets to enhance chemotherapy sensitivity in NB is of utmost importance. Increasing evidence implicates long noncoding RNAs (lncRNAs) play important roles in cancer, but their functional roles remain largely unexplored. Here, we analyzed our RNA sequencing data and identified the upregulated lncRNA ZNF674-AS1 in chemotherapy non-responsive NB patients. Elevated ZNF674-AS1 expression is associated with poor prognosis and high-risk NB. Importantly, targeting ZNF674-AS1 expression in NB cells suppressed tumor growth in vivo. Further functional studies have revealed that ZNF674-AS1 constrains cisplatin sensitivity by suppressing pyroptosis and promoting cell proliferation. Moreover, ZNF674-AS1 primarily relies on CA9 to fulfill its functions on cisplatin resistance. High CA9 levels were associated with high-risk NB and predicted poor patient outcomes. Mechanistically, ZNF674-AS1 directly interacted with the RNA binding protein IGF2BP3 to enhance the stability of CA9 mRNA by binding with CA9 transcript, leading to elevated CA9 expression. As a novel regulator of CA9, IGF2BP3 positively upregulated CA9 expression. Together, these results expand our understanding of the cancer-associated function of lncRNAs, highlighting the ZNF674-AS1/IGF2BP3/CA9 axis as a constituting regulatory mode in NB tumor growth and cisplatin resistance. These insights reveal the pivotal role of ZNF674-AS1 inhibition in recovering cisplatin sensitivity, thus providing potential therapeutic targets for NB treatment., (© 2024. The Author(s).)

Diesel exhaust particles (DEP) pollution should be taken seriously because it is an extensive environmental and occupational health concern. Exploring early effect biomarkers is crucial for monitoring and managing DEP-associated health risk assessment. Here, we found that serum levels of 67 miRNAs were dysregulated in DEP exposure group. Notably, 20 miRNAs were identified as each having a significant dose-response relationship with the internal exposure level of DEP. Further, we revealed that the DEP exposure could affect the liver function of subjects and that 7 miRNAs (including the well-known liver injury indicator, miR-122-5p) could serve as the novel epigenetic-biomarkers (epi-biomarkers) to reflect the liver-specific response to the DEP exposure. Importantly, an unprecedented prediction model using these 7 miRNAs was established for the assessment of DEP-induced liver injury risk. Finally, bioinformatic analysis indicated that the unique set of miRNA panel in serum might also contribute to the molecular mechanism of DEP exposure-induced liver damage. These results broaden our understanding of the adverse health outcomes of DEP exposure. Noteworthy, we believe this study could shed light on roles and functions of epigenetic biomarkers from environmental exposure to health outcomes by revealing the full chain of exposure-miRNAs-molecular pathways-disease evidence., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Numerous studies have revealed that ambient long-term exposure to fine particulate matter (PM 2.5 ) is significantly related to the development of lung cancer, but the molecular mechanisms of PM 2.5 exposure-induced lung cancer remains unknown. As an important epigenetic regulator, microRNAs (miRNAs) play vital roles in responding to environment exposure and various diseases including lung cancer development. Here we constructed a PM 2.5 -induced malignant transformed cell model and found that miR-200 family, especially miR-200a-3p, was involved in the process of PM 2.5 induced lung cancer. Further investigation of the function of miR-200 family (miR-200a-3p as a representative revealed that miR-200a-3p promoted cell migration by directly suppressing TNS3 expression. These results suggested that ambient PM 2.5 exposure may increase the expression of miR-200 family and then promote the proliferation and migration of lung cancer cells. Our study provided novel model and insights into the molecular mechanism of ambient PM 2.5 exposure-induced lung cancer., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

MiRNAs are widely acknowledged as regulating gene expression and thus, being involved in broad biological functions, environmental responses, and the process of diseases. Epidemiology could provide exposure- or disease-relevant miRNAs, while toxicology could reveal the underlying mechanisms. Here, a new "Bottom-up" approach was proposed to identify miRNAs that are responsible for environmental exposure-induced adverse outcomes. In our previous study, 5 key toxicity pathways were established underlying BaP-induced lung diseases; further, genes from these 5 pathways that were responsive to BaP exposure in HBE-CYP1A1 cells were identified. In this study, we identified 26 miRNA:mRNA interactions during BaP exposure through RNA-sequencing using the same HBE-CYP1A1 cells. According to the expression alteration and regulatory mechanisms, we summarized 8 action patterns of miRNA:mRNA, which led to the induction of miRNAs that predominantly regulate target genes and responsible are for the pathway perturbations (as "drivers"), and miRNAs that subordinately regulate genes during pathway perturbations (as "symptoms"). 5 corresponding miRNAs: miR-3173-5p, miR-629-3p, miR-9-5p, miR-1343-3p and miR-219a-1-3p were identified as "drivers", and were all validated with expression alteration in lung disease patients from published studies. In conclusion, this study offers a new approach to identification of epigenetic factors that may shed light on the causation of environment-related health outcomes., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

N, N-dimethylformamide (DMF) is a widely existing harmful environmental pollutant from industrial emission which can threat human health for both occupational and general populations. Epidemiological and experimental studies have indicated liver as the primary target organ of DMF. However, the molecular mechanism under DMF-induced hepatoxicity remains unclear. In the present study, we identified that DMF could induce abnormal autophagy flux in cells. We also showed that DMF-induced mitochondrial dysfunction and lethal mitophagy which further leads to autophagic cell death. Next, miRNA microarray analysis identified miR-92a-1-5p as the most down-regulated miRNA upon DMF exposure. Mechanistically, miR-92a-1-5p regulated mitochondrial function and mitophagy by targeting mitochondrial protein BNIP3L. Exogenous miR-92a-1-5p significantly attenuated DMF-induced mitochondrial dysfunction and mitophagy in vitro and in vivo. Our study highlights the mechanistic link between miRNAs and mitophagy under environmental stress, which provided a new clue for the mitochondrial epigenetics mechanism on environmental toxicant-induced hepatoxicity., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Alcohol dehydrogenases (ADHs) play vital roles in alcohol metabolism and alcohol toxicity, yet little is known about microRNA-mediated regulation of the ADH gene cluster. Here, we showed that miR-29c activated ADH gene cluster transcription by targeting an enhancer element within the ADH6 gene. miR-29c is differentially expressed in alcoholic liver disease. Following biochemical and molecular evidence demonstrated that miR-29c increased ADH6 mRNA and protein levels without affecting the stability of the ADH6 transcript. Further evidence showed that exogenous miR-29c translocated into the nucleus and then unconventionally bound an enhancer element within the ADH6 gene. Luciferase reporter assay and chromatin immunoprecipitation data indicated that miR-29c activated the enhancer and increased the enrichment of RNA polymerase II at the promoter regions of ADH1A, ADH1B, ADH1C, ADH4, and ADH6. Finally, exogenous miR-29c transfection promoted the expression of ADH1A, ADH1B, ADH1C, and ADH4 pre-mRNA and mRNA transcripts from the ADH gene cluster. In conclusion, our data suggest that miR-29c might be a novel epigenetic regulator involved in ADH gene cluster activation., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Background: To explore the clinical significance of miR-125b-5p and its potential mechanisms in lung squamous cell carcinoma (LUSC). Materials and Methods: An integrated analysis of data from in-house quantitative real-time polymerase chain reaction (qRT-PCR), microRNA-sequencing, and microarray assays to appraise the expression level of miR-125b-5p in LUSC tissues compared to adjacent noncancerous controls. The authors identified the candidate targets of miR-125b-5p and conducted functional analysis using computational biology strategies from gene ontology, the Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, disease ontology (DO), and protein-protein interaction (PPI) network analyses to investigate the prospective mechanisms. Results: According to qRT-PCR results, the expression level of miR-125b-5p was markedly decreased in LUSC tissues compared to noncancerous control tissues. Receiver operating characteristic and summary receiver operating characteristic analyses showed that miR-125b-5p had good specificity and sensitivity for distinguishing LUSC tissue from noncancerous lung tissue. The standard mean difference revealed that men and women with lower expression levels of miR-125b-5p may have a higher risk for LUSC. KEGG analysis and DO analysis intimated that target genes were evidently enriched in pyrimidine metabolism and pancreatic carcinoma. The PPI network of the top assembled KEGG pathway indicated that RRM2 , UMPS , UCK2 , and CTPS1 were regarded as crucial target genes for miR-125b-5p, and RRM2 was eventually deemed a key target. Conclusions: The authors' findings implicate a low expression level of miR-125b-5p in LUSC. A tumor-suppressive role of miR-125b-5p is proposed, based on its effects on LUSC tumor growth, clinical stage progression, and lymph node metastasis.

PM 2.5 (particles matter smaller aerodynamic diameter of 2.5 μm) exposure, a major environmental risk factor for the global burden of diseases, is associated with high risks of respiratory diseases. Heme-oxygenase 1 (HMOX1) is one of the major molecular antioxidant defenses to mediate cytoprotective effects against diverse stressors, including PM 2.5 -induced toxicity; however, the regulatory mechanism of HMOX1 expression still needs to be elucidated. In this study, using PM 2.5 as a typical stressor, we explored whether microRNAs (miRNAs) might modulate HMOX1 expression in lung cells. Systematic bioinformatics analysis showed that seven miRNAs have the potentials to target HMOX1 gene. Among these, hsa-miR-760 was identified as the most responsive miRNA to PM 2.5 exposure. More importantly, we revealed a "non-conventional" miRNA function in hsa-miR-760 upregulating HMOX1 expression, by targeting the coding region and interacting with YBX1 protein. In addition, we observed that exogenous hsa-miR-760 effectively elevated HMOX1 expression, reduced the reactive oxygen agents (ROS) levels, and rescued the lung cells from PM 2.5 -induced apoptosis. Our results revealed that hsa-miR-760 might play an important role in protecting lung cells against PM 2.5 -induced toxicity, by elevating HMOX1 expression, and offered new clues to elucidate the diverse functions of miRNAs., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The alcohol dehydrogenases (ADHs) and aldehyde dehydrogenases (ALDHs) play critical roles in alcoholism development and alcohol toxicology; however, few studies have focused on the miRNA-mediated mechanisms underlying the expressions of alcohol-metabolizing enzymes. In the present study, we showed the expression changes of each alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) in the liver samples of alcoholic hepatitis (AH) patients, and predicted the miRNAs targeting the dysregulated alcohol-metabolizing genes by a systematic in silico analysis. 13 miRNAs were predicted to regulate the expressions of ADH1A, ADH4, and ALDH2, respectively, with hsa-miR-148a-3p (miR-148a) showing the most significant down-regulation in AH patients. Following experimental evidence using HepG2 cells proved that miR-148a promoted ADH4 expression by directly binding to the coding sequence of ADH4 and increasing the mRNA stability via an AGO1-dependent manner. Additional assays showed that secondary structure of ADH4 transcript affected the target accessibility and binding of miR-148a-3p. In sum, our results suggest that the expressions of key alcohol-metabolizing enzymes are repressed in AH patients, and the non-canonical positive regulation of miR-148a on ADH4 reveals a new regulationary mechanism for ADH genes., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Cytochrome P450 (CYP) enzymes play critical roles in drug transformation, and the total CYPs are markedly decreased in alcoholic hepatitis (AH), a fatal alcoholic liver disease. miRNAs are endogenous small noncoding RNAs that regulate many essential biological processes. Knowledge concerning miRNA regulation of CYPs in AH disease is limited. Here we presented the changes of key CYPs in liver samples of AH patients retrieved from GEO database, performed in silico prediction of miRNAs potentially targeting the dysregulated CYP transcripts, and deciphered a novel mechanism underlying miRNA mediated CYPs expression in liver cells. Nine miRNAs were predicted to regulate CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C19, CYP2J2, and CYP3A4, among which hsa-miR-148a-3p was selected as a case study. Biochemical and molecular evidences demonstrated that miR-148a promoted CYP2B6 expression by increasing mRNA stability via directly binding to the 3'UTR sequence, and that this positive posttranscriptional regulation was AGO1/2-dependent. Further, luciferase reporter gene assay and RNA secondary structure analysis illustrated that the seedless target site, not the seed target site, controlled miR-148a-mediated CYP2B6 upregulation. Moreover, we identified HNF4A as a liver-specific transcription factor of MIR-148A through EMSA and chromatin immunoprecipitation experiments. In conclusion, ethanol downregulated miR-148a in hepatocytes through HNF4A regulation, which eventually decreased CYP2B6 expression. Our finding will benefit the understanding of dysregulated drug metabolism in AH patients and highlight an unconventional mechanism for epigenetic regulation of CYP gene expression., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Self-renewal and differentiation of spermatogonial stem cell (SSC) are critical for male fertility and reproduction, both of which are highly regulated by testicular microenvironment. Exosomal miRNAs have emerged as new components in intercellular communication. However, their roles in the differentiation of SSC remain unclear. Here, we observed miR-486-5p enriched in Sertoli cell and Sertoli cell-derived exosomes. The exosomes mediate the transfer of miR-486-5p from Sertoli cells to SSCs. Exosomes release miR-486-5p, thus up-regulate expression of Stra8 (stimulated by retinoic acid 8) and promote differentiation of SSC. And PTEN was identified as a target of miR-486-5p. Overexpression of miR-486-5p in SSCs down-regulates PTEN expression, which up-regulates the expression of STRA8 and SYCP3, promotes SSCs differentiation. In addition, blocking the exosome-mediated transfer of miR-486-5p inhibits differentiation of SSC. Our findings demonstrate that miR-486-5p acts as a communication molecule between Sertoli cells and SSCs in modulating differentiation of SSCs. This provides a new insight on molecular mechanisms that regulates SSC differentiation and a basis for the diagnosis, treatment, and prevention of male infertility., (© 2021 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Alcohol dehydrogenases (ADHs) and aldehyde dehydrogenases (ALDHs) are vital enzymes involved in the metabolism of a variety of alcohols. Differences in the expression and enzymatic activity of human ADHs and ALDHs correlate with individual variability in metabolizing alcohols and drugs and in the susceptibility to alcoholic liver disease. MicroRNAs (miRNAs) function as epigenetic modulators to regulate the expression of drug-metabolizing enzymes. To characterize miRNAs that target ADHs and ALDHs in human liver cells, we carried out a systematic bioinformatics analysis to analyze free energies of the interaction between miRNAs and their cognate sequences in ADH and ALDH transcripts and then calculated expression correlations between miRNAs and their targeting ADH and ALDH genes using a public data base. Candidate miRNAs were selected to evaluate bioinformatic predictions using a series of biochemical assays. Our results showed that 11 miRNAs have the potential to modulate the expression of two ADH and seven ALDH genes in the human liver. We found that hsa-miR-1301-3p suppressed the expression of ADH6 , ALDH5A1 , and ALDH8A1 in liver cells and blocked their induction by ethanol. In summary, our results revealed that hsa-miR-1301-3p plays an important role in ethanol metabolism by regulating ADH and ALDH gene expression. SIGNIFICANCE STATEMENT: Systematic bioinformatics analysis showed that 11 microRNAs might play regulatory roles in the expression of two alcohol dehydrogenase ( ADH ) and seven aldehyde dehydrogenase ( ALDH ) genes in the human liver. Experimental evidences proved that hsa-miR-1301-3p suppressed the expression of ADH6 , ALDH5A1 , and ALDH8A1 in liver cells and decreased their inducibility by ethanol., (Copyright © 2020 by The American Society for Pharmacology and Experimental Therapeutics.)

Bone marrow failure is a characteristic effect of benzene exposure. Our previous study has shown that miR-486-5p is involved in benzene induced-suppression of erythroid differentiation. However, the mechanism of miR-486-5p to initiate the above process remains unclear. In this study, we used miRTar software to predict putative miRNA targets and pathway. We found that miR-486-5p may target Ras-associated protein-1 (Rap1) signaling pathway-associated genes. Our in vitro study further showed significant dose-dependent upregulation of MAGI1 and RASSF5 expressions in hydroquinone (HQ)-induced suppression of erythroid differentiation of K562 cells. Over-expression or down-regulation of miR-486-5p altered MAGI1 and RASSF5 expression and modified erythroid differentiation. Dual-luciferase reporter assay and fluorescence-based RNA electrophoresis mobility assay (FREMSA) further confirmed that miR-486-5p directly bound to the 3'-untranslated region (3'-UTR) of MAGI1 and RASSF5. In addition, the expressions of RAPGEF2 and RAP1A, which are downstream genes of MAGI1, were also significantly increased when HQ inhibited erythroid differentiation. Knockdown of MAGI1 reversed HQ-induced inhibition of erythroid differentiation via downregulation of RAPGEF2, RAP1A and RASSF5. Together, these data indicate that miR-486-5p directly targets MAGI1 and RASSF5 and integrates with Rap1 signaling to modify HQ-induced inhibition of erythroid differentiation in K562 cells., Competing Interests: Declaration of Competing Interest The authors declare that there are not conflicts of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Lung squamous cell carcinoma (LUSC) is the main pathological type of pulmonary malignant tumors; at present, less than 10% of patients with advanced metastatic LUSC live for more than 5 years. We previously reported that low expression of miRNA-126-3p is associated with the occurrence and progression of lung adenocarcinoma (LUAD). Here, we examined expression of miRNA-126-3p in 23 samples from patients with LUSCs and 23 normal control specimens by quantitative real-time PCR (RT-qPCR). Associations between miRNA-126-3p expression and clinical features were studied from materials derived from Gene Expression Omnibus (GEO) chips and The Cancer Genome Atlas (TCGA) database. Twelve online platforms were used to identify candidate target genes of miRNA-126-3p. Further analyses of the Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and protein-protein interaction (PPI) network were performed on the target genes. GEO microarray analysis, TCGA data mining, RT-qPCR, and integration analysis consistently reported low expression of miRNA-126-3p in LUSC. A total of 42 genes were identified as potential target genes of miRNA-126-3p from online platforms, GEO microarrays, and the TCGA database. GO and KEGG analyses demonstrated that the target genes are involved in several biological processes that promote the progression of LUSC. SOX2, E2F2, and E2F3 were selected as hub genes from the PPI network for further analysis. In summary, our results suggest that the low expression of miRNA-126-3p may play a role in promoting the development of LUSC and miRNA-126-3p may be a biomarker for LUSC early diagnosis and prognosis., (© 2020 The Authors. Published by FEBS Press and John Wiley & Sons Ltd.)

Arsenic exposure contributed to the development of human diseases. Arsenic exerted multiple organ toxicities mainly by triggering oxidative stress. However, the signaling pathway underlying oxidative stress is unclear. We previously found that the expression of SFPQ, a splicing factor, was positively associated with urinary arsenic concentration in an arsenic-exposed population, suggesting an oxidative stress regulatory role for SFPQ. To test this hypothesis, we established cell models of oxidative stress in human hepatocyte cells (L02) treated with NaAsO 2 . Reactive oxygen species (ROS) synthesis displayed a time- and dose-dependent increase with NaAsO 2 treatment. SFPQ suppression resulted in a 36%-53% decrease in ROS generation, leading to enhanced cellular damage determined by 8-OHdG, comet tail moment, and micronucleus analysis. Particularly, SFPQ deficiency attenuated expression of the oxidase genes DUOX1, DUOX2, NCF2, and NOX2. A fluorescent-based RNA electrophoretic mobility shift assay (FREMSA) and dual-luciferase reporter system revealed that miR-92b-5p targeted DUOX2 mRNA degradation. An RNA immunoprecipitation assay showed an interaction between SFPQ and miR-92b-5p of the miRNA-induced silencing complex (miRISC). Notably, NaAsO 2 treatment diminished the interaction between SFPQ and miR92b-5p, accompanied by decreased binding between miR-92b-5p and 3'-UTR of DUOX2. However, SFPQ deficiency suppressed the dissociation of miR-92b-5p from 3'-UTR of DUOX2, indicating that miR-92b-5p regulated the SFPQ-dependent DUOX2 expression. Taken together, we reveal that SFPQ responds to arsenic-induced oxidative stress by interacting with the miRISC. These findings offer new insight into the potential role of SFPQ in regulating cellular stress response., Competing Interests: Declaration of competing interest All authors declared that they have no conflict of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Recent studies have shown that microRNAs and long noncoding RNAs (lncRNAs) regulate the expression of drug metabolizing enzymes (DMEs) in human hepatic cells and that a set of DMEs, including UDP glucuronosyltransferase (UGT) 2B15, is down-regulated dramatically in liver cells by toxic acetaminophen (APAP) concentrations. In this study we analyzed mRNA, microRNA, and lncRNA expression profiles in APAP-treated HepaRG cells to explore noncoding RNA-dependent regulation of DME expression. The expression of UGT2B15 and lncRNA LINC00574 was decreased in APAP-treated HepaRG cells. UGT2B15 levels were diminished by LINC00574 suppression using antisense oligonucleotides or small interfering RNA. Furthermore, we found that hsa-miR-129-5p suppressed LINC00574 and decreased UGT2B15 expression via LINC00574 in HepaRG cells. In conclusion, our results indicate that LINC00574 acts as an important regulator of UGT2B15 expression in human hepatic cells, providing experimental evidence and new clues to understand the role of cross-talk between noncoding RNAs. SIGNIFICANCE STATEMENT: We showed a molecular network that displays the cross-talk and consequences among mRNA, micro RNA, long noncoding RNA, and proteins in acetaminophen (APAP)-treated HepaRG cells. APAP treatment increased the level of hsa-miR-129-5p and decreased that of LINC00574, ultimately decreasing the production of UDP glucuronosyltransferase (UGT) 2B15. The proposed regulatory network suppresses UGT2B15 expression through interaction of hsa-miR-129-5p and LINC00574, which may be achieved potentially by recruiting RNA binding proteins., (Copyright © 2020 by The American Society for Pharmacology and Experimental Therapeutics.)

Aims: Recently, cancer-derived exosomes were shown to have pro-metastasis function in cancer, but the mechanism remains unclear. Angiogenesis is essential for tumor progression and is a great promising therapeutic target for advanced cervical cancer. Here, we investigated the role of cervical cancer cell-secreted exosomal miR-221-3p in tumor angiogenesis., Methods and Results: miR-221-3p was found to be closely correlated with microvascular density in cervical squamous cell carcinoma (CSCC) by evaluating the microvascular density with immunohistochemistry and miR-221-3p expression with in situ hybridization in clinical specimens. Using the groups of CSCC cell lines (SiHa and C33A) with miR-221-3p overexpression and silencing, the CSCC exosomes were characterized by electron microscopy, western blotting, and fluorescence microscopy. The enrichment of miR-221-3p in CSCC exosomes and its transfer into human umbilical vein endothelial cells (HUVECs) were confirmed by qRT-PCR. CSCC exosomal miR-221-3p promoted angiogenesis in vitro in Matrigel tube formation assay, spheroid sprouting assay, migration assay, and wound healing assay. Then, exosome intratumoral injection indicated that CSCC exosomal miR-221-3p promoted tumor growth in vivo. Thrombospondin-2 (THBS2) was bioinformatically predicted to be a direct target of miR-221-3p, and this was verified by using the in vitro and in vivo experiments described above. Additionally, overexpression of THBS2 in HUVECs rescued the angiogenic function of miR-221-3p., Conclusions: Our results suggest that CSCC exosomes transport miR-221-3p from cancer cells to vessel endothelial cells and promote angiogenesis by downregulating THBS2. Therefore, CSCC-derived exosomal miR-221-3p could be a possible novel diagnostic biomarker and therapeutic target for CSCC progression.