A DNA-based hydrogel for exosome separation and biomedical applications.

Exosomes (EXOs) have been proven as biomarkers for disease diagnosis and agents for therapeutics. Great challenge remains in the separation of EXOs with high-purity and low-damage from complex biological media, which is critical for the downstream applications. Herein, we report a DNA-based hydrogel to realize the specific and nondestructive separation of EXOs from complex biological media. The separated EXOs were directly utilized in the detection of human breast cancer in clinical samples, as well as applied in the therapeutics of myocardial infarction in rat models. The materials chemistry basis of this strategy involved the synthesis of ultralong DNA chains via an enzymatic amplification, and the formation of DNA hydrogels through complementary base-pairing. These ultralong DNA chains that contained polyvalent aptamers were able to recognize and bind with the receptors on EXOs, and the specific and efficient binding ensured the selective separation of EXOs from media into the further formed networked DNA hydrogel. Based on this DNA hydrogel, rationally designed optical modules were introduced for the detection of exosomal pathogenic microRNA, which achieved the classification of breast cancer patients versus healthy donors with 100% precision. Furthermore, the DNA hydrogel that contained mesenchymal stem cell-derived EXOs was proved with significant therapeutic efficacy in repairing infarcted myocardium of rat models. We envision that this DNA hydrogel-based bioseparation system is promising as a powerful biotechnology, which will promote the development of extracellular vesicles in nanobiomedicine.

Immune evasion strategy involving propionylation by the KSHV interferon regulatory factor 1 (vIRF1).

Post-translational modifications (PTMs) are essential for host antiviral immune response and viral immune evasion. Among a set of novel acylations, lysine propionylation (Kpr) has been detected in both histone and non-histone proteins. However, whether protein propionylation occurs in any viral proteins and whether such modifications regulate viral immune evasion remain elusive. Here, we show that Kaposi's sarcoma-associated herpesvirus (KSHV)-encoded viral interferon regulatory factor 1 (vIRF1) can be propionylated in lysine residues, which is required for effective inhibition of IFN-ß production and antiviral signaling. Mechanistically, vIRF1 promotes its own propionylation by blocking SIRT6's interaction with ubiquitin-specific peptidase 10 (USP10) leading to its degradation via a ubiquitin-proteasome pathway. Furthermore, vIRF1 propionylation is required for its function to block IRF3-CBP/p300 recruitment and repress the STING DNA sensing pathway. A SIRT6-specific activator, UBCS039, rescues propionylated vIRF1-mediated repression of IFN-ß signaling. These results reveal a novel mechanism of viral evasion of innate immunity through propionylation of a viral protein. The findings suggest that enzymes involved in viral propionylation could be potential targets for preventing viral infections.

Target-Triggered Aggregation of Modified E. coli for Diagnosis of Ovarian Cancer.

Bacteria inherently possess the capability of quorum sensing in response to the environment. In this work, we have proposed a strategy to confer bacteria with the ability to recognize targets with quorum-sensing behavior. Meanwhile, we have successfully achieved artificial control over the target-triggered aggregation of Escherichia coli (E. coli) by modifying the bacteria surface in a new way. Furthermore, by making use of green fluorescent protein (GFP) expressed by E. coli as the output signal, the aggregation of modified E. coli can be observed with the naked eye. Therefore, via the detection of the target, MUC1, an ovarian cancer biomarker, a simple and conveniently operated method to diagnose ovarian cancer is developed in this work. Experimental results show that the developed low-background and enzyme-free amplification method enables the highly sensitive detection of MUC1, achieving a remarkable limit of detection (LOD) of 5.47 fM and a linear detection range spanning from 1 pM to 50 nM and 50 nM to 100 nM, respectively. Clinical samples from healthy donors and patients can give distant assay results, showing great potential for clinical applications of this method.

Research Progress on the Assembly of Large DNA Fragments.

Synthetic biology, a newly and rapidly developing interdisciplinary field, has demonstrated increasing potential for extensive applications in the wide areas of biomedicine, biofuels, and novel materials. DNA assembly is a key enabling technology of synthetic biology and a central point for realizing fully synthetic artificial life. While the assembly of small DNA fragments has been successfully commercialized, the assembly of large DNA fragments remains a challenge due to their high molecular weight and susceptibility to breakage. This article provides an overview of the development and current state of DNA assembly technology, with a focus on recent advancements in the assembly of large DNA fragments in Escherichia coli, Bacillus subtilis, and Saccharomyces cerevisiae. In particular, the methods and challenges associated with the assembly of large DNA fragment in different hosts are highlighted. The advancements in DNA assembly have the potential to facilitate the construction of customized genomes, giving us the ability to modify cellular functions and even create artificial life. It is also contributing to our ability to understand, predict, and manipulate living organisms.

Correction: Sperm associated antigen 9 promotes oncogenic KSHV-encoded interferon regulatory factor-induced cellular transformation and angiogenesis by activating the JNK/VEGFA pathway.

[This corrects the article DOI: 10.1371/journal.ppat.1008730.].

IGF2BP2 promotes ovarian cancer growth and metastasis by upregulating CKAP2L protein expression in an m6 A-dependent manner.

Ovarian cancer (OC) is the second leading cause of gynecological cancer-related death in women worldwide. N6-methyladenosine (m6 A) is the most abundant internal modification in eukaryotic RNA. Human insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2), an m6 A reader, can enhance mRNA stability and promote translation by recognizing m6 A modifications. Its tumor-promoting effects have been demonstrated in several cancers. However, the roles of m6 A modification and IGF2BP2 in OC remain unclear. Here, by using methylated RNA immunoprecipitation sequencing, we demonstrated that there is widespread dysregulation of m6 A modification in OC tissues. The m6 A modification and the mRNA and protein levels of IGF2BP2 were significantly elevated in OC. Overexpression of IGF2BP2 facilitated OC cell proliferation, migration, and invasion in vitro and accelerated tumor growth and metastasis in vivo. While IGF2BP2-knockdown showed the opposite effect. Mechanistically, we identified cytoskeleton-associated protein 2-like (CKAP2L) as a target of IGF2BP2. IGF2BP2 promoted CKAP2L translation dependent on m6 A modification, rather than affecting mRNA and protein stability. Overexpression of CKAP2L rescued the tumor-suppressive effect of IGF2BP2 knockdown in OC cells. In conclusion, this study revealed the potential role of IGF2BP2 in tumor progression, at least partially via promoting the translation of CKAP2L in an m6 A-dependent manner.

Tripartite-motif 3 represses ovarian cancer progression by downregulating lactate dehydrogenase A and inhibiting AKT signaling.

The E3 ubiquitin ligase Tripartite-motif 3 (TRIM3) is known to play a crucial role in tumor suppression in various tumors through different mechanisms. However, its function and mechanism in ovarian cancer have yet to be elucidated. Our study aims to investigate the expression of TRIM3 in ovarian cancer and evaluate its role in the development of the disease. Our findings revealed a significant decrease in TRIM3 mRNA and protein levels in ovarian cancer tissues and cells when compared to normal ovarian epithelial tissues and cells. Furthermore, we observed a negative correlation between the protein level of TRIM3 and the FIGO stage, as well as a positive correlation with the survival of ovarian cancer patients. Using gain and loss of function experiments, we demonstrated that TRIM3 can inhibit cell proliferation, migration and invasion of the ovarian cancer cells in vitro, as well as suppress tumor growth in vivo. Mechanistic studies showed that TRIM3 interacts with lactate dehydrogenase A, a key enzyme in the glycolytic pathway, through its B-box and coiled-coil domains and induces its ubiquitination and proteasomal degradation, leading to the inhibition of glycolytic ability in ovarian cancer cells. RNA-sequencing analysis revealed significant alterations in the phosphatidylinositol signaling pathways upon TRIM3 overexpression. Additionally, overexpression of TRIM3 inhibited the phosphorylation of AKT. In conclusion, our study demonstrated that TRIM3 exerts a tumor-suppressive effect in ovarian cancer, at least partially, by downregulating LDHA and inhibiting the AKT signaling pathway, and thus leading to the inhibition of glycolysis and limiting the growth of ovarian cancer cells.

Asparagine: A key metabolic junction in targeted tumor therapy.

Nutrient bioavailability in the tumor microenvironment plays a pivotal role in tumor proliferation and metastasis. Among these nutrients, glutamine is a key substance that promotes tumor growth and proliferation, and its downstream metabolite asparagine is also crucial in tumors. Studies have shown that when glutamine is exhausted, tumor cells can rely on asparagine to sustain their growth. Given the reliance of tumor cell proliferation on asparagine, restricting its bioavailability has emerged as promising strategy in cancer treatment. For instance, the use of asparaginase, an enzyme that depletes asparagine, has been one of the key chemotherapies for acute lymphoblastic leukemia (ALL). However, tumor cells can adapt to asparagine restriction, leading to reduced chemotherapy efficacy, and the mechanisms by which different genetically altered tumors are sensitized or adapted to asparagine restriction vary. We review the sources of asparagine and explore how limiting its bioavailability impacts the progression of specific genetically altered tumors. It is hoped that by targeting the signaling pathways involved in tumor adaptation to asparagine restriction and certain factors within these pathways, the issue of drug resistance can be addressed. Importantly, these strategies offer precise therapeutic approaches for genetically altered cancers.

Long noncoding RNA RFPL1S-202 inhibits ovarian cancer progression by downregulating the IFN-ß/STAT1 signaling.

BACKGROUND: RFPL1S was first identified as one of the pseudogenes located in the intrachromosomal duplications within 22q12-13. Our previous study found that one of the predicted transcripts of lncRNA RFPL1S, ENST00000419368.1 (GRCh37/hg19), also named as RFPL1S-202 in Ensembl website, is significantly downregulated in the chemoresistant ovarian cancer cells. However, its function and underlying mechanism have not been studied. METHODS: Quantitative Real-time PCR was used to analyze the expression. Cell Counting Kit-8, transwell, flow cytometry analysis and tail vein injected mouse model were used to test the function. RNA-sequencing, RNA pull down, western blot, ELISA and RNA-Binding Protein Immunoprecipitation were performed for studying the mechanism. 5' and 3' rapid amplification of complementary DNA ends were performed to analyze the full length of RFPL1S-202. RESULTS: RFPL1S-202 is significantly downregulated in epithelial ovarian cancer tissues and cell lines. Gain- and loss-of-function study indicated that RFPL1S-202 could enhance cisplatin or paclitaxel in cytotoxicity, inhibit cell proliferation, invasion and migration of ovarian cancer cells in vitro, and inhibit the liver metastasis of ovarian cancer cells in vivo. Mechanistically, RFPL1S-202 could physically interact with DEAD-Box Helicase 3 X-linked (DDX3X) protein, and decrease the expression of p-STAT1 and the IFN inducible genes by increasing the m6A modification of IFNB1. RFPL1S-202 is a spliced and polyadenylated non-coding RNA with a full length of 1071 bp. CONCLUSIONS: Our study suggested that the predicted lncRNA RFPL1S-202 exerts a tumor- suppressive function in oarian cancer chemoresistance and progression by interacting with DDX3X and down-regulating the IFN-ß-STAT1 signaling pathway.

Analysis of the Secreted Peptidome from Omental Adipose Tissue in High-Grade Serous Ovarian Cancer.

High-grade serous ovarian cancer (HGSOC) is a preferential omental metastasis malignancy. Since omental adipose tissue is an endocrine organ, we used liquid chromatography tandem mass spectrometry (LC-MS/MS) to compare the peptides secreted from omental adipose tissues of HGSOC and benign serous ovarian cysts (BSOC). Among the differentially secreted peptides, we detected 58 upregulated peptides, 197 downregulated peptides, 24 peptides that were only in the HGSOC group and 20 peptides that were only in the BSOC group (absolute fold change ≥ 2 and P < 0.05). Then, the basic characteristics of the differential peptides were analyzed, such as lengths, molecular weights, isoelectric points, and cleavage sites. Furthermore, we summarized the possible functions according to the precursor protein functions of the differentially expressed peptides by Gene Ontology (GO) analysis with the Annotation, Visualization, and Integrated Discovery (DAVID) database and canonical pathway analysis with IPA. For the GO analysis, the differentially secreted peptides were mainly associated with binding in molecular function and cellular processes in biology process. For the canonical pathways, the differentially secreted peptides were related to calcium signaling, protein kinase A signaling, and integrin-linked kinase (ILK) signaling. We also identified 67 differentially secreted peptides that located in the functional domains of the precursor proteins. These functional domains were mainly related to energy metabolism and immunoregulation. Our study might provide drugs that could potentially treat HGSOC or omental metastases of HGSOC cells.

LncRNA SLC25A21-AS1 increases the chemosensitivity and inhibits the progression of ovarian cancer by upregulating the expression of KCNK4.

Owing to high mortality rate, ovarian cancer seriously threatens women's health. Extensive abdominal metastasis and chemoresistance are the leading causes of ovarian cancer deaths. Through lncRNA sequencing, our previous study identified lncRNA SLC25A21-AS1, which was significantly downregulated in chemoresistant ovarian cancer cells. In this study, we aimed to evaluate the role and mechanism of SLC25A21-AS1 in ovarian cancer. The expression of SLC25A21-AS1 was analyzed by qRT-PCR and online database GEPIA. The biological functions of SLC25A21-AS1 and KCNK4 were analyzed by CCK-8, transwell, and flow cytometry. The specific mechanism was analyzed by RNA-sequencing, RNA binding protein immunoprecipitation, rescue experiments, and bioinformatic analysis. SLC25A21-AS1 was decreased in ovarian cancer tissues and cell lines. Overexpression of SLC25A21-AS1 enhanced the sensitivity of ovarian cancer cells to paclitaxel and cisplatin, and inhibited cell proliferation, invasion, and migration, while SLC25A21-AS1-silencing showed the opposite effect. Potassium channel subfamily K member 4 (KCNK4) was significantly up-regulated upon enforced expression of SLC25A21-AS1. Overexpression of KCNK4 inhibited cell proliferation, invasion, migration ability, and enhanced the sensitivity of ovarian cancer cells to paclitaxel and cisplatin. Meanwhile, KNCK4-overexpression rescued the promotive effect of SLC25A21-AS1-silencing on cell proliferation, invasion and migration. In addition, SLC25A21-AS1 could interact with the transcription factor Enhancer of Zeste Homolog 2 (EZH2), while EZH2 knockdown increased the expression of KCNK4 in some of the ovarian cancer cell lines. SLC25A21-AS1 enhanced the chemosensitivity and inhibited the proliferation, migration, and invasion ability of ovarian cancer cells at least partially by blocking EZH2-mediated silencing of KCNK4.

CircRNA ARFGEF1 functions as a ceRNA to promote oncogenic KSHV-encoded viral interferon regulatory factor induction of cell invasion and angiogenesis by upregulating glutaredoxin 3.

Circular RNAs (circRNAs) are novel single-stranded noncoding RNAs that can decoy other RNAs to inhibit their functions. Kaposi's sarcoma (KS), caused by oncogenic Kaposi's sarcoma-associated herpesvirus (KSHV), is a highly angiogenic and invasive vascular tumor of endothelial origin commonly found in AIDS patients. We have recently shown that KSHV-encoded viral interferon regulatory factor 1 (vIRF1) induces cell invasion, angiogenesis and cellular transformation; however, the role of circRNAs is largely unknown in the context of KSHV vIRF1. Herein, transcriptome analysis identified 22 differentially expressed cellular circRNAs regulated by vIRF1 in an endothelial cell line. Among them, circARFGEF1 was the highest upregulated circRNA. Mechanistically, vIRF1 induced circARFGEF1 transcription by binding to transcription factor lymphoid enhancer binding factor 1 (Lef1). Importantly, upregulation of circARFGEF1 was required for vIRF1-induced cell motility, proliferation and in vivo angiogenesis. circARFGEF1 functioned as a competing endogenous RNAs (ceRNAs) by binding to and inducing degradation of miR-125a-3p. Mass spectrometry analysis demonstrated that glutaredoxin 3 (GLRX3) was a direct target of miR-125a-3p. Knockdown of GLRX3 impaired cell motility, proliferation and angiogenesis induced by vIRF1. Taken together, vIRF1 transcriptionally activates circARFGEF1, potentially by binding to Lef1, to promote cell oncogenic phenotypes via inhibiting miR-125a-3p and inducing GLRX3. These findings define a novel mechanism responsible for vIRF1-induced oncogenesis and establish the scientific basis for targeting these molecules for treating KSHV-associated cancers.

Circular RNA hsa_circ_0007444 inhibits ovarian cancer progression through miR-23a-3p/DICER1 axis.

Ovarian cancer is the second leading cause of death in women with gynecological malignancy in China. Circular RNAs are a class of noncoding regulatory RNAs reported to be involved in cancer development and progression. Previous studies, including our own, have indicated that hsa_circ_0007444 is downregulated in ovarian cancer tissues. This study aims to elucidate the function and mechanism of hsa_circ_0007444 in ovarian cancer progression. The expression of hsa_circ_0007444 is determined by quantitative real-time PCR (qRT-PCR). Cell proliferation, invasion, migration and apoptosis are examined by cell counting-kit 8 (CCK-8), transwell and flow cytometry assays. Tumor growth and metastasis are assessed in vivo using Balb/c nude mouse xenograft model and tail vein injection model. And the mechanism of action of hsa_circ_0007444 is analysed by RNA-binding protein immunoprecipitation (RIP), luciferase reporter and rescue assays. hsa_circ_0007444 is downregulated in ovarian cancer tissues and cell lines compared with that in normal ovarian tissues and normal epithelial cell line. Gain- and loss-of-function results indicate that hsa_circ_0007444 inhibits cell proliferation, invasion, migration and increases cell apoptosis of ovarian cancer cells in vitro, and inhibits tumor growth and lung metastasis in vivo. Mechanistically, hsa_circ_0007444 can interact with AGO2 and sponge miR-23a-3p, thereby upregulating DICER1 expression, which is an important tumor suppressor in ovarian cancer. And miR-23a-3p mimics can rescue the inhibitory effect of hsa_circ_0007444 on ovarian cancer cell proliferation, invasion and migration. Therefore, hsa_circ_0007444 can inhibit ovarian cancer progression through the hsa_circ_0007444/miR-23a-3p/DICER1 axis.

Circulating CD4+ Treg, CD8+ Treg, and CD3+ γδ T Cell Subpopulations in Ovarian Cancer.

Background and Objectives: Regulatory T cells (Tregs) are usually enriched in ovarian cancer (OC), and their immunosuppressive function plays a key role in tumorigenesis and progression. We mainly explored the phenotypical characterization of Treg-related markers on αß and γδ T cell subsets in patients with OC. Materials and Methods: Thirty-six untreated patients with OC at the Women's Hospital of Nanjing Medical University from September 2019 to August 2021 were enrolled. Phenotypical characterization of Tregs-related markers were detected by flow cytometry (FCM). Enzyme-linked immunosorbent assay was used to detect the levels of carbohydrate antigen (CA125) and transforming growth factor ß (TGF-ß). The level of human epididymis protein 4 (HE4) was detected by electrochemiluminescence immunoassay. Results: Circulating CD4+ Tregs, CD8+ Tregs, and CD3+γδ T cell subpopulations from OC patients have elevated Foxp3, CD25, CD122, Vδ1, and reduced CD28 expression compared to benign ovarian tumor (BOT) patients and healthy controls (HC). The upregulation of Foxp3 and Vδ1 and the downregulation of CD28 were highly specific for maintaining the immunosuppression function of CD4+ Tregs, CD3+γδ T cells, and CD8+ Tregs in OC patients. These Treg subpopulations were able to discriminate OC from BOT and HC. The levels of CA125, HE4, and TGF-ß were increased in OC patients. A significant positive correlation between Treg subpopulations and CA125, HE4, and TGF-ß was revealed. Conclusions: Proportions of CD4+ Tregs, CD8+ Tregs, and CD3+γδ T cell subsets were significantly increased in OC patients and were positively correlated with FIGO stage/metastasis status, CA125, HE4, and TGF-ß. These indicators have the potential to be used as immunosurveillance biomarkers for OC.

Sperm associated antigen 9 promotes oncogenic KSHV-encoded interferon regulatory factor-induced cellular transformation and angiogenesis by activating the JNK/VEGFA pathway.

Kaposi's sarcoma (KS), caused by Kaposi's sarcoma-associated herpesvirus (KSHV), is a highly angioproliferative disseminated tumor of endothelial cells commonly found in AIDS patients. We have recently shown that KSHV-encoded viral interferon regulatory factor 1 (vIRF1) mediates KSHV-induced cell motility (PLoS Pathog. 2019 Jan 30;15(1):e1007578). However, the role of vIRF1 in KSHV-induced cellular transformation and angiogenesis remains unknown. Here, we show that vIRF1 promotes angiogenesis by upregulating sperm associated antigen 9 (SPAG9) using two in vivo angiogenesis models including the chick chorioallantoic membrane assay (CAM) and the matrigel plug angiogenesis assay in mice. Mechanistically, vIRF1 interacts with transcription factor Lef1 to promote SPAG9 transcription. vIRF1-induced SPAG9 promotes the interaction of mitogen-activated protein kinase kinase 4 (MKK4) with JNK1/2 to increase their phosphorylation, resulting in enhanced VEGFA expression, angiogenesis, cell proliferation and migration. Finally, genetic deletion of ORF-K9 from KSHV genome abolishes KSHV-induced cellular transformation and impairs angiogenesis. Our results reveal that vIRF1 transcriptionally activates SPAG9 expression to promote angiogenesis and tumorigenesis via activating JNK/VEGFA signaling. These novel findings define the mechanism of KSHV induction of the SPAG9/JNK/VEGFA pathway and establish the scientific basis for targeting this pathway for treating KSHV-associated cancers.

Efficient Charge Carrier Transfer Route Induced by an S-Scheme α-Fe2O3/RP Heterojunction with Enhanced Photocatalytic Activity of Overall Water Splitting.

Photocatalytic overall water splitting simultaneously generates O2 and H2; this is a potential strategy to solve the energy shortage problem. Elemental phosphorus (RP) displays ultralow visible light performance for O2 and H2 generation; thus, a novel α-Fe2O3/RP composite is designed and prepared by a low-temperature hydrothermal method via loading a trace amount of α-Fe2O3. In the experiment, the 1.5% α-Fe2O3/RP composite showed the best overall water splitting performance, which is 6.9 times that of bare RP. Through various characterization studies, the recombination rate of charges is significantly reduced. It is largely ascribed to the matched energy band structure of the two photocatalysts and the interface contact between α-Fe2O3 and RP, which efficiently separates the photocarriers through an S-scheme mode and realizes the obvious enhancement of overall water splitting performance. Moreover, α-Fe2O3/RP maintains high activity when it is persistently irradiated for 15 cycles. The research provides insight into the exploitation of low-cost, high-activity, and stable RP-based photocatalysts to achieve visible light induced overall water splitting activity to generate O2 and H2.

A DNA Nanocomplex Containing Cascade DNAzymes and Promoter-Like Zn-Mn-Ferrite for Combined Gene/Chemo-dynamic Therapy.

Sequential control of exogenous chemical events inside cells is a promising way to regulate cell functions and fate. Herein we report a DNA nanocomplex containing cascade DNAzymes and promoter-like Zn-Mn-Ferrite (ZMF), achieving combined gene/chemo-dynamic therapy. The promoter-like ZMF decomposed in response to intratumoral glutathione to release a sufficient quantity of metal ions, thus promoting cascade DNA/RNA cleavage and free radical generation. Two kinds of DNAzymes were designed for sequential cascade enzymatic reaction, in which metal ions functioned as cofactors. The primary DNAzyme self-cleaved the DNA chain with Zn2+ as cofactor, and produced the secondary DNAzyme; the secondary DNAzyme afterwards cleaved the EGR-1 mRNA, and thus downregulated the expression of target EGR-1 protein, achieving DNAzyme-based gene therapy. Meanwhile, the released Zn2+ , Mn2+ and Fe2+ induced Fenton/Fenton-like reactions, during which free radicals were catalytically generated and efficient chemo-dynamic therapy was achieved. In a breast cancer mouse model, the administration of DNA nanocomplex led to a significant therapeutic efficacy of tumor growth suppression.

Long noncoding RNA ZEB1-AS1 affects paclitaxel and cisplatin resistance by regulating MMP19 in epithelial ovarian cancer cells.

PURPOSE: The long noncoding RNA (lncRNA) ZEB1-AS1 is reported overexpressed in sensitive ovarian cancer cells A2780 compared with paclitaxel (PTX)-and cisplatin (DDP)- resistant. However, the function and mechanism of ZEB1-AS1 in EOC cells still unknown. METHODS: We used quantitative real-time PCR (qPCR) to detect ZEB1-AS1 expression in A2780 and A2780/R cells. A combination of siRNA, plasmids, CCK8 and flow cytometry was used to detect the effect of ZEB1-AS1 on ovarian cancer cell A2780 PTX and DDP resistance. Transcriptome sequencing, qPCR, and western blot were used for further mechanistic studies. RESULTS: ZEB1-AS1 depletion using siRNA in chemosensitive A2780 cells significantly increased PTX and DDP resistance. In contrast, ZEB1-AS1 overexpression in PTX- and DDP-resistant A2780/resistant (A2780/R) cells reversed the observed drug resistance. Thus, ZEB1-AS1 plays an important role in PTX and DDP resistance in EOC cells. However, quantitative real-time PCR (qPCR) and western blot results suggested that ZEB1-AS1 did not regulate chemoresistance through regulation of ZEB1 protein. We used sequencing to detect mRNA expression changes in A2780 cells after ZEB1-AS1 silencing. The results indicated that MMP19 was the likely downstream factor of ZEB1-AS1. We further examined whether ZEB1-AS1 played an important role in chemoresistance by silencing MMP19 in ZEB1-AS1-overexpressing cells. CCK8 assay results suggested that MMP19 knockdown promoted ZEB1-AS1-induced chemoresistance to PTX and DDP in A2780 cells. CONCLUSION: This study is the first to reveal that ZEB1-AS1 plays a pivotal role in cancer chemoresistance.

Multidrug resistant lncRNA profile in chemotherapeutic sensitive and resistant ovarian cancer cells.

Most ovarian cancer patients are chemosensitive initially, but finally relapse with acquired chemoresistance. Multidrug-resistance is the extremely terrible situation. The mechanism for the acquired chemoresistance of ovarian cancer patients is still not clear. LncRNAs have been recognized as the important regulator of a variety of biological processes, including the multidrug-resistant process. Here, we carried out the lncRNA sequencing of the ovarian cancer cell line A2780 and the paxitaxel resistant cell line A2780/PTX which is also cross resistant to the cisplatin and epirubicin. Through integrating the published data with the cisplatin resistant lncRNAs in ovarian cancer cell line or ovarian cancer patients, 5 up-regulated and 21 down-regulated lncRNAs are considered as the multidrug-resistant lncRNAs. By real-time PCR analysis, we confirmed the 5 up-regulated and 4 down-regulated multidrug resistant lncRNAs were similarly changed in both the multidrug resistant ovarian cancer cell lines and the multidrug resistant colon cancer cell lines. Furthermore, we conducted the lncRNA-mRNA co-expression network to predict the potential multidrug resistant lncRNAs' targets. Interestingly, the multidrug resistant genes ABCB1, ABCB4, ABCC3, and ABCG2 are all co-expressed with lncRNA CTD-2589M5.4. Our results provide the valuable information for the understanding of the lncRNA function in the multidrug resistant process.

[Effect of germ cell Wdr1 deletion on the ovarian function of mice].

OBJECTIVE: To study the effect of Wdr1 deletion in germ cells on ovarian function of mice. METHODS: Oocyte-specific gene knockout mouse model was constructed by crossing Wdr1fl/flfemale mice with Cre recombinase transgenic male mice which was driven by a germ cell-specific promoter. Wdr1fl/-; Ddx4-Cre mice and control mice were sacrificed at 14 days, 28 days and 4 months after birth, whose ovaries were subjected to photography, paraffin sectioning and Hematoxylin-Eosin (HE) staining. The ovarian volume and follicular numbers were recorded at various time points. RESULTS: The ovarian volume of Wdr1 fl/-; Ddx4-Cre mice was slightly lower than that of the controls at 14 days. HE staining showed that primordial follicles, primary follicles and secondary follicles were slightly reduced compared with the control mice at 14 days. The ovarian volume of Wdr1 fl/-; Ddx4-Cre mice was significantly lower than that of the control mice at 28 days and 4 months. HE staining showed that all developmental follicles were significantly reduced compared with the control mice. CONCLUSION: Wdr1 gene deletion in germ cells can influence early ovarian function of mice and lead to premature ovarian failure.