Uterine leiomyosarcoma cell-derived extracellular vesicles induce the formation of cancer-associated fibroblasts.

OBJECTIVE: Uterine leiomyosarcoma (ULMS) is a rare malignant tumor, which is aggressive, and has a poor prognosis even during its early stages. Extracellular vesicles (EVs) carry cargo, such as microRNAs (miRNAs), which are involved in intercellular communication in the tumor microenvironment and other processes. Because there are no studies on EV-related miRNAs in ULMS, we identified EV-related miRNAs in ULMS and examined their function. METHODS: Small EVs (sEVs) and medium/large EVs (m/lEVs) were extracted from ULMS cells by ultracentrifugation and their basic characteristics were evaluated. Then, small RNA sequencing was done to obtain EV-related miRNA profiles. Next, miRNA expression levels in sera and tissues of ULMS patients were compared with those of myoma patients. RESULTS: miR-654-3p and miR-369-3p were indicated to be highly expressed in both sera and tissues of ULMS patients. These two miRNAs are also highly expressed in ULMS cell lines and ULMS-derived EVs. Some cancer-associated fibroblast (CAF) markers were increased when fibroblasts were treated with ULMS-derived EVs. Furthermore, fibroblasts took up EVs derived from ULMS as determined by confocal laser microscopy. In addition, the transfection of the two candidate miRNAs into fibroblasts significantly increased some CAF markers, particularly ACTA2. CONCLUSION: miR-654-3p and miR-369-3p are highly expressed in ULMS-derived EVs, indicating that these EV-related miRNAs induce the formation of cancer-associated fibroblasts.

Small extracellular vesicles in follicular fluids for predicting reproductive outcomes in assisted reproductive technology.

BACKGROUND: Assisted reproductive technology accounts for an increasing proportion of infertility treatments, and assessments to predict clinical pregnancy outcomes are desired. Extracellular vesicles exist in follicular fluid, and small non coding RNAs in extracellular vesicles underline the possibility of reflecting pregnancy potential. METHODS: Follicular fluid samples are collected from 20 ovarian follicles of 15 infertile patients undergoing assisted reproductive technology. Extracellular vesicles are isolated by serial centrifugation and small RNA sequencing is performed to investigate the profiles of microRNAs and P-element-induced wimpy testis-interacting RNAs. RESULTS: Small extracellular vesicles with a size range of approximately 100 nm are successfully isolated, and the small non coding RNA profiles of pregnant samples (n = 8) are different from those of non-pregnant samples (n = 12). Fourteen dysregulated small non coding RNAs are selected to identify the independent candidates [mean read count >100, area under the curve >0.8]. Among them, we find that a specific combination of small non coding RNAs (miR-16-2-3p, miR-378a-3p, and miR-483-5p) can predict the pregnant samples more precisely using a receiver operating characteristics curves analysis (area under the curve: 0.96). Furthermore, even in the same patients, the three microRNAs are differentially expressed between pregnant and non-pregnant samples. CONCLUSIONS: Our results demonstrate that small non coding RNAs derived from small extracellular vesicles in follicular fluid can be potential non-invasive biomarkers for predicting pregnancy, leading to their probable application in assisted reproductive technology. Further large-scale studies are required to validate the clinical usefulness of these small non coding RNAs.

Assisted reproductive technologies (ART) are medical procedures used to address infertility. Follicular fluid (FF)is a liquid that surrounds the immature egg cells (oocytes) and provides hormones and nutrients necessary for their maturation and eventual development into embryos. We analyzed genetic components within the FF as a potential predictor of reproductive outcomes following ART. Here, we show that a specific combination of genetic elements produced by the FF in successful pregnancies did not occur in unsuccessful pregnancies. Our findings may help to provide a non-invasive approach to determining reproductive outcomes during ART procedures.

Leucine zipper protein 1 (LUZP1) regulates the constriction velocity of the contractile ring during cytokinesis.

There has been a great deal of research on cell division and its mechanisms; however, its processes still have many unknowns. To find novel proteins that regulate cell division, we performed the screening using siRNAs and/or the expression plasmid of the target genes and identified leucine zipper protein 1 (LUZP1). Recent studies have shown that LUZP1 interacts with various proteins and stabilizes the actin cytoskeleton; however, the function of LUZP1 in mitosis is not known. In this study, we found that LUZP1 colocalized with the chromosomal passenger complex (CPC) at the centromere in metaphase and at the central spindle in anaphase and that these LUZP1 localizations were regulated by CPC activity and kinesin family member 20A (KIF20A). Mass spectrometry analysis identified that LUZP1 interacted with death-associated protein kinase 3 (DAPK3), one regulator of the cleavage furrow ingression in cytokinesis. In addition, we found that LUZP1 also interacted with myosin light chain 9 (MYL9), a substrate of DAPK3, and comprehensively inhibited MYL9 phosphorylation by DAPK3. In line with a known role for MYL9 in the actin-myosin contraction, LUZP1 suppression accelerated the constriction velocity at the division plane in our time-lapse analysis. Our study indicates that LUZP1 is a novel regulator for cytokinesis that regulates the constriction velocity of the contractile ring.

Small Extracellular Vesicles from adipose-derived stem cells suppress cell proliferation by delivering the let-7 family of microRNAs in ovarian cancer.

INTRODUCTION: Ovarian cancer is the leading cause of death among women with gynecological cancer, and novel treatment options are urgently needed. Extracellular vesicles (EVs), including exosomes, may be one of the most promising therapeutic tools for various diseases. In this study, we aimed to investigate the therapeutic effects of adipose-derived stem cell-derived EVs (ADSC-EVs) on ovarian cancer cell lines. MATERIALS AND METHODS: ADSCs and the ovarian cancer cell lines SKOV3 and OV90 were used for analysis. ADSC-EVs were isolated through ultracentrifugation and validated using a cryotransmission electron microscope, nanoparticle tracking analysis, and western blotting. Then, the effect of ADSC-EVs on ovarian cancer cells was investigated using IncuCyte and microRNA sequencing. Moreover, the potential functions of miRNAs were evaluated by gain-of function analysis and in silico analysis. RESULTS: ADSC-EVs suppressed SKOV3 and OV90 cell proliferation. In particular, small EVs (sEVs) from ADSCs exhibited a stronger antitumor effect than ADSC-medium/large EVs (m/lEVs). Comparison of the miRNA profiles between ADSC-sEVs and ADSC-m/lEVs, along with downstream pathway analysis, suggested the involvement of the let-7 family. Overexpression of hsa-let-7b-5p and hsa-let-7e-5p significantly suppressed the proliferation of SKOV3 cells. In silico analysis revealed that four potential target genes of hsa-let-7b-5p and hsa-let-7e-5p were significantly associated with the prognoses of the patients. CONCLUSION: ADSC-sEVs had a stronger antitumor effect than ADSC-m/lEVs. Hsa-let-7b-5p and hsa-let-7e-5p, which are highly abundant in ADSC-sEVs, suppressed cell proliferation. These findings may open up new possibilities for therapeutic approaches using ADSC-sEVs.

Identifying high-grade serous ovarian carcinoma-specific extracellular vesicles by polyketone-coated nanowires.

Cancer cell-derived extracellular vesicles (EVs) have unique protein profiles, making them promising targets as disease biomarkers. High-grade serous ovarian carcinoma (HGSOC) is the deadly subtype of epithelial ovarian cancer, and we aimed to identify HGSOC-specific membrane proteins. Small EVs (sEVs) and medium/large EVs (m/lEVs) from cell lines or patient serum and ascites were analyzed by LC-MS/MS, revealing that both EV subtypes had unique proteomic characteristics. Multivalidation steps identified FRα, Claudin-3, and TACSTD2 as HGSOC-specific sEV proteins, but m/lEV-associated candidates were not identified. In addition, for using a simple-to-use microfluidic device for EV isolation, polyketone-coated nanowires (pNWs) were developed, which efficiently purify sEVs from biofluids. Multiplexed array assays of sEVs isolated by pNW showed specific detectability in cancer patients and predicted clinical status. In summary, the HGSOC-specific marker detection by pNW are a promising platform as clinical biomarkers, and these insights provide detailed proteomic aspects of diverse EVs in HGSOC patients.

The association of UBAP2L and G3BP1 mediated by small nucleolar RNA is essential for stress granule formation.

Stress granules (SGs) are dynamic, non-membranous structures composed of non-translating mRNAs and various proteins and play critical roles in cell survival under stressed conditions. Extensive proteomics analyses have been performed to identify proteins in SGs; however, the molecular functions of these components in SG formation remain unclear. In this report, we show that ubiquitin-associated protein 2-like (UBAP2L) is a crucial component of SGs. UBAP2L localized to SGs in response to various stresses, and its depletion significantly suppressed SG organization. Proteomics and RNA sequencing analyses found that UBAP2L formed a protein-RNA complex with Ras-GTP-activating protein SH3 domain binding protein 1 (G3BP1) and small nucleolar RNAs (snoRNAs). In vitro binding analysis demonstrated that snoRNAs were required for UBAP2L association with G3BP1. In addition, decreased expression of snoRNAs reduced the interaction between UBAP2L and G3BP1 and suppressed SG formation. Our results reveal a critical role of SG component, the UBAP2L/snoRNA/G3BP1 protein-RNA complex, and provide new insights into the regulation of SG assembly.

Novel therapeutic strategies targeting UCP2 in uterine leiomyosarcoma.

Uterine leiomyosarcoma (ULMS) is a malignant stromal tumor arising from the myometrium with a poor prognosis and very limited response to current chemotherapy. This study aimed to identify novel targets for ULMS through a three-step screening process using a chemical library consisting of 1271 Food and Drug Administration-approved drugs. First, we evaluated their inhibitory effects on ULMS cells and identified four candidates: proscillaridin A, lanatoside C, floxuridine, and digoxin. Then, we subcutaneously or orthotopically transplanted SK-UT-1 cells into mice to establish mouse models. In vivo analyses showed that proscillaridin A and lanatoside C exerted a superior antitumor effect. The results of mRNA sequencing showed that uncoupling protein 2 (UCP2) was suppressed in the sirtuin signaling pathway, increasing reactive oxygen species (ROS) and inducing cell death. Moreover, the downregulation of UCP2 induced ROS and suppressed ULMS cell growth. Furthermore, analyses using clinical samples showed that UCP2 expression was significantly upregulated in ULMS tissues than in myoma tissues both at the RNA and protein levels. These findings suggested that UCP2 is a potential therapeutic target and can contribute to the development of novel therapeutic strategies in patients with ULMS.

Clinical Significance of Ubiquitin-associated Protein 2-like in Patients With Uterine Cervical Cancer.

BACKGROUND: Ubiquitin-associated protein 2-like (UBAP2L) has been demonstrated to be associated with the progression of multiple types of cancer. However, the function of UBAP2L in uterine cervical cancer remains unclear. MATERIALS AND METHODS: Between 2005 and 2015, 84 patients who underwent surgery were included in this study. The patients were stratified into two groups on the basis of immunohistochemical staining for UBAP2L, and survival analysis was performed. Moreover, loss-of-function analysis was performed using the cervical cancer cell lines CaSki and SiHa. RESULTS: Based on immunohistochemistry, the overall survival in patients with low UBAP2L expression was significantly longer than that of those with high UBAP2L expression (p=0.045). The in vitro experiment revealed that knockdown of UBAP2L remarkably inhibited cell proliferation in both live cell imaging and the MTS assay. CONCLUSION: Patients with high UBAP2L expression had unfavorable prognosis and UBAP2L appears to play an important role in proliferation.

FAM98A is localized to stress granules and associates with multiple stress granule-localized proteins.

Stress granules are evolutionally conserved ribonucleoprotein structures that are formed in response to various stress stimuli. Recent studies have demonstrated that proteins with low complexity (LC) regions play a critical role for the formation of stress granules. In this study, we report that FAM98A, whose biological functions are unknown, is a novel component of stress granules. FAM98A is localized to stress granules, but not to P-bodies, after various stress stimuli. Analysis with deletion mutants revealed that C-terminal region that contains LC region was essential for FAM98A accumulation to stress granules. Depletion of FAM98A using two different siRNAs decreased the number of stress granules formed per cell. Finally, we show that FAM98A associates with stress granule-localized proteins, such as DDX1, ATXN2, ATXN2L, and NUFIP2. Our results show a partial role of FAM98A for the organization of stress granules.

Phosphorylation of DEPDC1 at Ser110 is required to maintain centrosome organization during mitosis.

DEPDC1 (DEP domain containing 1) is overexpressed in multiple cancers and is associated with cell cycle progression. In this report, we have investigated the expression, localization, phosphorylation and function of DEPDC1 during mitosis. DEPDC1 has two isoforms (isoform a and isoform b), and both of them are increased in mitosis and degraded once cells exit mitosis. DEPDC1a is localized to the centrosome in metaphase, whereas DEPDC1b is localized to the entire cell cortex during mitosis. DEPDC1a, but not DEPDC1b, was required for the integrity of centrosome and organization of the bipolar spindle. Mass spectrometry and biochemical analyses revealed phosphorylation of DEPDC1 at Ser110. The phosphorylation of Ser110 is essential for localization of DEPDC1a to the centrosome. Consistently, non-phosphorylation mutants of DEPDC1a did not rescue disruption of centrosome organization by depletion of endogenous DEPDC1. Our results show a novel role for DEPDC1 in maintaining centrosome integrity during mitosis for the accurate distribution of chromosomes.

A regulatory subunit of protein phosphatase 2A, PPP2R5E, regulates the abundance of microtubule crosslinking factor 1.

Dynamic changes in microtubule organization are regulated by numerous microtubule-associating proteins and their post-translational modification. Microtubule crosslinking factor 1 (MTCL1) is a recently identified protein that regulates microtubule organization. To obtain further insight into its functions, we searched for proteins that associate with it using mass spectrometry analysis. We found that PPP2R5E, a regulatory subunit of protein phosphatase 2A, interacted with MTCL1. Depletion of PPP2R5E reduced the abundance of MTCL1 abundance, whereas exogenous expression of PPP2R5E increased endogenous MTCL1. Furthermore, inhibition of phosphatase activity by okadaic acid reduced MTCL1, which was restored by the addition of the protease inhibitor MG132. Finally, we show that cells depleted of PPP2R5E and MTCL1 exhibited defects in microtubule organization. Our results suggest that the PPP2R5E phosphatase may contribute to microtubule organization by stabilizing MTCL1.