Growth Of Ovarian Carcinoma Research Articles

Co‐encapsulation of Curcumin and Paclitaxel using Non‐ionic Surfactant Based Nanovesicles Suppresses Growth of Ovarian Carcinoma through the Inhibition of Nuclear Factor κB and AKT1

AbstractCurcumin (Cur) indicates P‐glycoprotein inhibitory activity by downregulating the nuclear factor (NF)‐κB signaling and the PI3K/AKT/mTOR pathway. Curcumin has limited due to its low water‐solubility. Therefore, using novel chemotherapeutic nanoformulations of curcumin or combining it with paclitaxel (PCL) may be more effective against cancer. Recently, we demonstrated that the combination of chemotherapy with PCL and Cur, using non‐ionic surfactant‐based nano‐vesicles (NISV), exhibited enhanced synergistic anticancer efficacy in breast cancer cells. However, the effect of combining these drugs using non‐ionic surfactant‐based nano‐vesicles for treating ovarian cancer, particularly in terms of their influence on AKT1 and NF‐kappa B, has not been investigated. Hereupon, we decided to investigate the single and combination treatment with Cur and PCL on cell apoptosis, expression of the AKT‐1 gene, and determination of p65‐NF‐κB in OVCAR‐3 cell. The combination of chemotherapy with curcumin and paclitaxel, using NISV, resulted in a higher rate of apoptosis, more efficient reduction in AKT‐1 gene expression (91.2 % reduction in PCL‐NISV+Cur‐NISV vs. 72.89 % reduction in PCL+Cur free solution), and 79.42 % reduction in NF‐κB activity compared to individual treatments. The findings indicate that combining curcumin and paclitaxel using non‐ionic surfactant‐based nano‐vesicles may be a promising strategy for reducing ovarian cancer growth.

CBX8 Together with SET Facilitates Ovarian Carcinoma Growth and Metastasis by Suppressing the Transcription of SUSD2.

Our study uncovers a novel mechanism CBX8 explores to execute gene repression, and provides new therapeutic targets for ovarian carcinoma.

Retracted] Downregulation of matrix metalloproteinase9 by small interfering RNA inhibits the tumor growth of ovarian epithelial carcinoma invitro and invivo.

Following the publication of this paper, the authors contacted the Editorial Office to request that the article be retracted on account of an inability to obtain consistent results after having repeated the experiments portrayed in Figs.1B and 3B. Independently, it was drawn to the Editor's attention that certain of the western blotting data shown in these figures were strikingly similar to data appearing in different form in other articles by different authors. Owing to the fact that these other articles were under consideration for publication at the same time as the above article was submitted for publication to Molecular Medicine Reports, the Editor has agreed to the authors' request that this article should be retracted from the Journal. The Editor apologizes to the readership for any inconvenience caused. [the original article was published in Molecular Medicine Reports 12: 753‑759, 2015; DOI: 10.3892/mmr.2015.3425].

Retracted] miR‑338‑3p suppresses tumor growth of ovarian epithelial carcinoma by targeting Runx2.

Following the publication of this paper, it was drawn to the Editors' attention by a concerned reader that the western blotting data shown in Fig.5C and D bore unexpected similarities to data appearing in different form in other articles by different authors. Owing to the fact that some of the contentious data in the above article had already been published elsewhere, or were already under consideration for publication, prior to its submission to Internatiοnal Journal of Oncology, the Editor has decided that this paper should be retracted from the Journal. After having been in contact with the authors, they agreed with the decision to retract the paper. The Editor apologizes to the readership for any inconvenience caused. [the original article was published in International Journal of Oncology 46: 2277‑2285, 2015; DOI: 10.3892/ijo.2015.2929].

RETRACTED: Differential expression of miR-130a-3p modulate ovarian epithelial carcinoma (OEC) cell development and could be a biomarker for OEC

A lot of research investigations, conducted in the recent years, establishes that microRNAs (miRNAs) have an important role in keeping both growth and metastasis of Ovarian Epithelial Carcinoma (OEC) under control. However, the clinical and functional role of miR-130a-3p in OEC is yet to be explored. Through quantitative reaction i.e., qRT-PCR, the expression of miR-130a-3p was assessed in tissues and cell lines of OEC patients. This analysis determined the relationship between the expression of miR-130a-3p and its clinicopathology with the overall survival rate of OEC patients. The author made use of cell counting analysis (CCK8) and in vitro flow cytometry to understand the functional and biological impact of miR-130a-3p expression. In comparison with neighboring normal tissues, the expression of miR-130a-3p was found to be lower in 7 OEC samples. Few reasons are cited for this scenario i.e., low expression of miR-130a-3p, such as low overall OEC patient survival rate, incidence of FIGO and metastasis of lymph nodes. miR-130a-3p has been found as an independent candidate for predicting the prognosis of OEC patients, as per Multivariate Cox research. When miR-130a-3p is over-expressed, as per the enhanced mechanism, it prevents both cell proliferation and cell cycle production in OEC. The current study findings emphasize that miR-130a-3p can be leveraged as a biomarker of prognosis and possibly as a target in the treatment of OEC.

Retracted: Pleuromutilin Inhibits Proliferation and Migration of A2780 and Caov-3 Ovarian Carcinoma Cells and Growth of Mouse A2780 Tumor Xenografts by Down-Regulation of pFAK2.

Some cells or groups of cells in figures appear to be visible multiple times. Because the manuscript contains non-credible results this journal is retracting the above publication. Reference:Bo Zhang, Xiaoli Ma, Yuan Li, Sijing Li, Jiumei Cheng: Pleuromutilin Inhibits Proliferation and Migration of A2780 and Caov-3 Ovarian Carcinoma Cells and Growth of Mouse A2780 Tumor Xenografts by Down-Regulation of pFAK2. Med Sci Monit, 2020; 26: e920407. DOI: 10.12659/MSM.920704.

Redox-sensitive carrier-free nanoparticles self-assembled by disulfide-linked paclitaxel-tetramethylpyrazine conjugate for combination cancer chemotherapy.

Rationale: Combinations of two or more therapeutic agents targeting different signaling pathways involved in tumor progression can have synergistic anticancer effects. However, combination chemotherapies are greatly limited by the different pharmacokinetics, tumor targeting, and cellular uptake capacities of the combined drugs. We have previously demonstrated the potential synergistic efficacy of paclitaxel (PTX) and the natural anti-angiogenic agent tetramethylpyrazine (TMP) for suppressing ovarian carcinoma growth. An efficient, facile, and smart nanosystem to deliver PTX and TMP simultaneously in vivo is greatly desired.Methods: We constructed a redox-sensitive nanosystem based on the amphiphilic PTX-ss-TMP conjugate, in which PTX and TMP are linked by a disulfide bond. We characterized the structure of the drug conjugate by 1H NMR and LC-MS, and then prepared PTX-ss-TMP NPs by a one-step nanoprecipitation method. We investigated the redox sensitivity, tumor-targeting ability, anticancer efficacy, and anti-angiogenesis activity of PTX-ss-TMP NPs in vitro and in vivo.Results: The amphiphilic PTX-ss-TMP conjugate readily self-assembled into stable nanoparticles in aqueous solution with a low critical association concentration of 1.35 µg/mL, well-defined spherical structure, small particle size (152 nm), high drug loading, redox-responsive drug release, high biocompatibility, and high storage stability. In cancer cells pretreated with GSH-OEt, PTX-ss-TMP NPs exhibited higher cytotoxicity, apoptosis rate, and cell-cycle arrest than monotherapy or combination therapy with free drugs, which was attributed to their improved cellular uptake and rapid intracellular drug release. Additionally, PTX-ss-TMP NPs also had a stronger anti-angiogenesis effect in HUVECs than free drug, which was mediated by VEGFR2-involved downstream signals. Finally, PTX-ss-TMP NPs showed tumor-specific accumulation and excellent antitumor activity in A2780 xenograft mice compared with free drug.Conclusions: These in vitro and in vivo results provide clear evidence that this redox-responsive carrier-free nanosystem with intrinsic amphiphilicity has great potential for combination cancer chemotherapy.

Long noncoding RNA HOTTIP promotes the metastatic potential of ovarian cancer through the regulation of the miR-615-3p/SMARCE1 pathway.

Upregulation of lncRNA HOXA transcript at the distal tip (HOTTIP) plays important roles in cancer progression. Nevertheless, its functions in the growth and metastasis of ovarian carcinoma are unknown. In this study, we demonstrated overexpression of HOTTIP in ovarian cancer cell lines and clinical tissues. Further, we showed that higher level of HOTTIP was associated with poor survival of ovarian cancer patients. Notably, HOTTIP silencing restrained proliferation, migration, and invasiveness of ovarian carcinoma cells. On the other hand, upregulation of HOTTIP remarkably exacerbated the aggressive traits of ovarian carcinoma cells. In addition, HOTTIP served as a sponge of miR-615-3p to upregulate SMARCE1 level. Further, upregulation of miR-615-3p or downregulation of SMARCE1 reversed the carcinogenic impacts of HOTTIP in ovarian cancer. HOTTIP and miR-615-3p expression levels in ovarian cancer cells were negatively correlated, whereas HOTTIP and SMARCE1 expression levels were positively correlated. In nude mice, downregulation of HOTTIP reduced cell growth in vivo. In summary, lncRNA HOTTIP promotes the growth and metastatic phenotypes of ovarian cancer via regulating miR-615-3p/SMARCE1 pathway.

Pleuromutilin Inhibits Proliferation and Migration of A2780 and Caov-3 Ovarian Carcinoma Cells and Growth of Mouse A2780 Tumor Xenografts by Down-Regulation of pFAK2.

BackgroundPleuromutilin is a natural tricyclic, derived from the fungus, Pleurotus mutilus. This study aimed to investigate the effects of pleuromutilin on migration and proliferation of A2780 and Caov-3 human ovarian carcinoma cells and the growth of A2780 tumor xenografts in mice and the molecular mechanisms involved.Material/MethodsA2780 and Caov-3 human ovarian carcinoma cells were cultured with and without 40, 160, and 200 μM of pleuromutilin. The Edu fluorescence assay, the wound-healing assay, and Matrigel were used to measure A2780 and Caov-3 cell proliferation, migration, invasion, and adhesion in vitro, respectively. Western blot measured protein levels of FAK, p-FAK, MMP-2, and MMP-9. A2780 cells were injected subcutaneously into mice to determine the effects of pleuromutilin on the growth of tumor xenografts.ResultsPleuromutilin significantly reduced A2780 and Caov-3 cell proliferation at 48 h in a dose-dependent manner (P<0.05), and at 200 μM, pleuromutilin reduced cell proliferation by 21.43% and 23.65%, respectively. Treatment of A2780 cells with pleuromutilin significantly reduced cell migration, invasion, and adhesion and the expression of p-FAK, MMP-2, and MMP-9 compared with untreated controls. In the mouse tumor xenograft model, treatment with pleuromutilin significantly reduced tumor size compared with the untreated group and inhibited tumor metastasis to the intestine, spleen, and peritoneal cavity.ConclusionsIn A2780 and Caov-3 human ovarian carcinoma cells, pleuromutilin inhibited cell proliferation, migration, invasion, and adhesion in a dose-dependent manner, and reduced tumor growth and metastases in a mouse A2780 cell tumor xenograft model.

Niclosamide inhibits ovarian carcinoma growth by interrupting cellular bioenergetics.

Background: Ovarian carcinoma is a common malignant tumor of the female reproductive organs with an incidence rate second only to cervical and endometrial cancers. In the past 10 years, anticancer therapy has focused on Niclosamide, an anthelmintic teniacide that is commonly used against tapeworms and has been approved for use in humans for nearly 50 years. Importantly, Niclosamide has been confirmed to target the Wnt/β-catenin, mTOR, STAT3, NF-κB, and Notch pathways has been widely investigated in multiple cancer types. However, the potential benefits of Niclosamide therapy for treatment of ovarian carcinoma have not been established.Methods: CCK-8 colony formation assays were performed to evaluate cell viability and tumor growth. Cell apoptosis was measured by flow cytometry. A Seahorse XF96 analyzer was used to measure cellular bioenergetics. Mito-tracker stained mitochondria were visualized by confocal microscopy. Western blotting was used to detect expressed proteins. A nude mouse transplanted-tumor model was used to evaluate the antitumor activity of Niclosamide in ovarian carcinoma.Result: Niclosamide treatment significantly suppressed ovarian carcinoma growth and induced cell apoptosis by inactivating MEK1/2-ERK1/2 mediated signal transduction. Overall, mitochondrial respiration and aerobic glycolysis were both decreased by Niclosamide treatment. Niclosamide dramatically enhanced ROS-activated and JNK-mediated apoptosis in cells subjected to glucose deprivation. Niclosamide also showed in vivo antitumor activity in the nude mouse transplanted-tumor model.Conclusion: Collectively, these data highlight a novel anti-tumor mechanism of Niclosamide that involves an interruption of cell metabolism. The finding also indicates a potential for the application of Niclosamide in ovarian carcinoma therapy.

Ginsenoside-Rg5 inhibits growth and metastasis of ovarian carcinoma via suppressing expression of fibroblast growth factor-8b (FGF8b)

Ginsenoside-Rg5, a protopanaxadiol ginsenoside originates from ginseng, is known for its anti-cancer activities. This study aimed to explore the underlying mechanism of ginsenoside-Rg5 on ovarian carcinoma. We found that 10 µM–50 µM of ginsenoside-Rg5 could reduce viability, adhesive capacity and migration potential of ovarian cancer OCI-P9a culture cells in a dose dependent manner. Treatment of ovarian cancer mice using 25 mg/kg of ginsenoside-Rg5 for one month could significantly reduce tumor volume (165.5 ± 29.6 mm3 in treated group versus 979.2 ± 134.5 mm3 in control group). In contrast to control mice, no tumor metastasis was seen in ginsenoside-Rg5 treated mice. OCI-P9a cells were found to have a high level of fibroblast growth factor-8 (FGF8b) expression, and ginsenoside-Rg5 could significantly reduce the expression of FGF8b in these cells. Therefore, anti-cancer and anti-metastasis effects of ginsenoside-Rg5 may be related with FGF8b-associated pathways. This ginsenoside from ginseng can be a good therapy candidate for ovary cancer.

Phenethyl isothiocyanate hampers growth and progression of HER2-positive breast and ovarian carcinoma by targeting their stem cell compartment.

Isothiocyanates elicit anticancer effects by targeting cancer stem cells (CSCs). Here, we tested the antitumor activity of phenethyl-isothiocyanate (PEITC), either alone or in combination with trastuzumab, in HER2-positive tumor models. We assessed the in vitro anticancer activity of PEITC, alone or combined with trastuzumab, in HER2-positive BT474, SKBR3, HCC1954 and SKOV3 cancer cells by measuring their sphere forming efficiency (SFE). The expression of the human/rodent CSC biomarkers aldehyde-dehydrogenase (ALDH) and CD29High/CD24+/Sca1Low was evaluated by cytofluorimetric analysis. The expression of wild type HER2 (WTHER2), its splice variant d16HER2 and NOTCH was analysed by quantitative RT-PCR and Western blotting. The in vivo activity of PEITC and trastuzumab was evaluated in mice orthotopically implanted with MI6 tumor cells transgenic for the human d16HER2 splice isoform. Magnetic resonance imaging/spectroscopy and immunohistochemistry were used to assess morpho-functional and metabolic profiles of treated versus untreated mice. We found that PEITC significantly impaired the SFE of HER2-positive human cancer cells by decreasing their ALDH-positive compartments. The anti-CSC activity of PEITC was demonstrated by a reduced expression/activation of established cancer-stemness biomarkers. Similar results were obtained with MI6 cells, where PEITC, alone or in combination with trastuzumab, significantly inhibited their SFE. We also found that PEITC hampered the in vivo growth of MI6 nodules by inducing hemorrhagic and necrotic intra-tumor areas and, in combination with trastuzumab, by significantly reducing spontaneous tumor development in d16HER2 transgenic mice. Our results indicate that PEITC targets HER2-positive CSCs and that its combination with trastuzumab may pave the way for a novel therapeutic strategy for HER2-positive tumors.

Liquid Biopsies for Ovarian Carcinoma: How Blood Tests May Improve the Clinical Management of a Deadly Disease.

Ovarian cancers (OvC) are frequent, with more than 22,000 new cases each year for 14,000 deaths in the United States. Except for patients with BRCA1 or BRCA2 mutations, diagnostic methods, prognostic tools, and therapeutic strategies have not much improved in the last two decades. High throughput tumor molecular analyses have identified important alterations involved in ovarian carcinoma growth and spreading. However, these data have not modified the clinical management of most of patients. Moreover, tumor sample collection requires invasive procedures not adapted to objectives, such as the screening, prediction, or assessment of treatment efficacy, monitoring of residual disease, and early diagnosis of relapse. In recent years, circulating tumor biomarkers (also known as “liquid biopsies”) such as circulating tumor cells, circulating nucleotides (DNA or miRNA), or extracellular vesicles, have been massively explored through various indications, platforms, and goals, but their use has not yet been validated in routine practice. This review describes the methods of analysis and results related to liquid biopsies for ovarian epithelial cancer. The different settings that a patient can go through during her journey with OvC are explored: screening and early diagnosis, prognosis, prediction of response to systemic therapies for advanced stages, and monitoring of residual subclinical disease.

Dinaciclib persistently inhibits patient-derived high-grade ovarian carcinoma growth

Dinaciclib persistently inhibits patient-derived high-grade ovarian carcinoma growth

Bovine milk-derived exosomes mediated delivery of resibufogenin and its effect on platinum-resistant ovarian carcinoma.

e17065 Background: Platinum-resistant ovarian carcinoma presents poor prognosis owing to its chemotherapeutic resistance. Resibufogenin is a kind of traditional Chinese medicine with potential anti-cancer ability. Exosomes are naturally occurring membrane particles that mediate intercellular communication by delivering molecular information between cells. The purpose of the current study was to evaluate the effect of bovine-milk-derived exosomes as carriers of resibufogenin to Platinum-resistant ovarian carcinoma and investigate the mechanism. Methods: Exosomes were isolated from bovine-milk using differential centrifugation and characterized by electron microscopy, nanoparticle tracking analysis, and western blot. Drug screening among 172 traditional Chinese medicines to find out resibufogenin. The exosomes were loaded with resibufogenin and the effectiveness of exosome-mediated drug was assessed with viability assay, transwell assay and flow cytometry assay. The distribution of exosome-delivered resibufogenin in cells was inspected by confocal microscopy. Xenograft mouse models were constructed to clarify the treatment response in vivo. mRNA sequencing assay, qPCR assay, immunohistochemistry assay and western blotting assay were used to detect and verify the targeted pathways. Results: Our main finding that resibufogenin inhibits the proliferation, migration and invasion in platinum-resistant ovarian carcinoma. Bovine-milk-derived exosomes delivered resibufogenin into platinum-resistant ovarian carcinoma and enhanced the cytotoxicity of resibufogenin. In vivo experiment demonstrated that resibufogenin suppressed the growth of xenograft tumors, with lower ki-67 expression and higher tunel expression. The mRNA sequencing assay, qPCR assay, immunohistochemistry assay and western blotting assay showed that the PI3K/AKT and Regulation of actin cytoskeleton signaling pathways account for the results above. Conclusions: Bovine-milk-derived exosomes can be used as effective carriers of resibufogenin to platinum-resistant ovarian carcinoma. Bovine-milk-derived exosomes-loading resibufogenin inhibits platinum-resistant ovarian carcinoma growth and migration in vitro and in vivo through PI3K/AKT and Regulation of actin cytoskeleton signaling pathway.

METTL3 promotes ovarian carcinoma growth and invasion through the regulation of AXL translation and epithelial to mesenchymal transition

ObjectiveAs the most prevalent internal modification in mammalian messenger RNA, N6‑methyladenosine (m6A) plays an important role in posttranscriptional gene regulation. METTL3 is a key component of the m6A methyltransferase complex and has recently been shown to play important roles in cancer development and progression. The current study was aimed to explore the function and underlying mechanism of METTL3 in ovarian cancer. MethodsMETTL3 expression was assessed by immunohistochemistry in 162 ovarian carcinoma patients. Stable cell lines with METTL3 gene overexpression or knockdown were established to investigate the function of METTL3 in ovarian cancer in vitro and in vivo. ResultsMETTL3 was frequently upregulated in ovarian carcinoma and that a high level of METTL3 was significantly associated with tumor grade (P = 0.001), pT status (P = 0.002), pN/pM status (P < 0.001), FIGO stage (P < 0.001), and overall survival rate (P < 0.001). Stable overexpression of METTL3 in the OVCAR3 and COV504 cell lines significantly increased cellular proliferation, focus formation, motility, invasion, and tumor formation in nude mice. Silencing METTL3 expression in the SKOV3 and HO-8910 cell lines with short hairpin RNA effectively inhibited its oncogenic function. Further study found that METTL3 promoted epithelial-mesenchymal transition (EMT) by upregulating the receptor tyrosine kinase AXL. ConclusionOur findings suggest that METTL3 plays very important oncogenic roles in ovarian carcinoma development and/or aggressiveness by stimulating AXL translation and EMT and that METTL3 may serve as a novel prognostic and/or therapeutic target of interest in ovarian cancer.

Abstract LB-253: Suppression of clear cell ovarian carcinoma growth by glutaminase-1 inhibitor as single agent and in combination with PARP-1 inhibitor

Abstract Tumor hypoxia and cancer-associated mutations reprogram central carbon metabolism and enhance the dependence of cancer cells on glutamine for growth. Clear cell ovarian cancer (CCOC) is a unique epithelial ovarian cancer histotype that is less responsive to chemotherapy and has poorer prognosis than serous histotype. Whole genomic analysis identified major pathways activated in clear cell involving in hypoxic cell growth and carbohydrate metabolism, which were driven by hypoxia-inducible factors HIF1a and/or 2a. We demonstrated before that treatment of HIF-expressing cancer cells with glutaminase 1 (GLS1) inhibitor CB-839, restricts nucleotide synthesis and causes DNA replication stress, which sensitizes cells to the PARP-1 inhibitor. Herein, we observed a range of sensitivities to CB-839 treatment in vitro in CCOC cell lines, from which we selected 4 most sensitive cell lines (ES2, SMOV2, TOV21G and RMG1) and 4 most resistant cell lines (OVSAYO, KK, HAC2 and OVISE) for further study. The synergistic effect of combination treatment of CB-839 and olaparib was achieved in all eight cell lines in vitro. To identify more molecular and metabolic biomarkers of CCOC sensitivity to GLS1 inhibitors, we are currently profiling the gene expression signatures of the most sensitive and resistant CCOC cell lines by RNAseq as well as and the metabolic profile of the CCOC lines. To test the sensitivity of the ES2 cells in vivo to a GLS1 as a single agent or in combination with PARP-1 inhibitors we injected them orthotopically in nude mice. Thirty mice bearing growing ES2 derived tumors were randomly assigned into four groups: vehicle control (n=8), treatment with CB-839 (200mg/kg, gavage, twice daily, n=7), olaparib (75mg/kg, gavage, once daily, n=7) or their combination (n=8). We monitored tumor growth by serial bioluminescence imaging, animal body weight as well as animal survival. To date, after 15-day treatment, we detected a synergistic effect between the 2 agents CB-839 and olaparib in controlling ovarian tumor growth in vivo. Our work discovered a range of sensitivities of CCOC cell lines to GLS1 inhibitor and supports the therapeutic strategies of combining GLS1 inhibitor and PARP inhibitor for targeting HIF-driven CCOC. Citation Format: Tianjin Yi, Danos Christodoulou, Arimichi Okazaki, Michael Birrer, Othon Iliopoulos. Suppression of clear cell ovarian carcinoma growth by glutaminase-1 inhibitor as single agent and in combination with PARP-1 inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr LB-253.

Cross-linked hyaluronan gel inhibits the growth and metastasis of ovarian carcinoma

BackgroundThe recurrence, metastasis and poor prognosis are important characteristics of ovarian carcinoma (OC), which are associated with exfoliation of cells from the primary tumor and colonization of the cells in pelvic cavity. On the other hand, the life quality of the patients undergoing surgical resection of OC was influenced by postoperative adhesions. Therefore, preventing postoperative implant tumor and adhesion may be effective methods to improve OC treatment. HyaRegen Gel, a cross-linked hyaluronan gel (CHAG), has been widely used as an anti-adhesive agent following pelvic operation in clinic. However, whether it can affect the implantation and growth of OC cells or not is still not clear.MethodsMigration and invasion assays were applied to detect the effect of CHAG on migration and invasion of OC cells. Western blotting was performed to detect the phosphorylation/activation of EGFR and ERK, and the expression of PCNA and MMP7. Pull down assay was used to analyze the effect of CHAG on the activation of small G protein Rac1. Nude mice implantation tumor model was applied to observe the effect of CHAG on implantation tumor of OC cells.ResultsThe results of in vitro experiments showed that CHAG suppressed both basic and EGF-induced migration and invasion of OC cells, blocked the activation of EGF-initiated EGFR activation, inhibited downstream signal transduction of EGFR, and decreased expression of proliferation and migration/invasion related proteins. Meanwhile, results of in vivo experiments showed that CHAG not only inhibited the formation of implantation tumor of OC cells but also delayed the of the growth of the tumors.ConclusionsCHAG inhibited migration, invasion and proliferation of OC cells in vitro, and suppressed development of implantation tumor of OC in vivo. This made it as both anti-tumor and anti-adhesion agents.

Down-regulation of HECTD3 by HER2 inhibition makes serous ovarian cancer cells sensitive to platinum treatment

Resistance to platinum-based chemotherapy is a major cause of treatment failure in patients with epithelial ovarian cancer and predicts a poor prognosis. Previously, we found that HECTD3 confers cancer cell resistance to apoptosis. However, the significance of HECTD3 expression in ovarian cancer and its regulatory mechanisms were unknown. Here, we found that HECTD3 depletion promotes carboplatin-induced apoptosis in both an ovarian cancer cell model and a xenograft mouse model. Moreover, high HECTD3 expression is significantly associated with poor platinum response and prognosis in ovarian cancer patients. We further demonstrated that HER2 can up-regulate HECTD3 expression through activating STAT3. Furthermore, HER2 inhibitors, such as lapatinib, down-regulate HECTD3 expression and thus promote the chemosensitivity of ovarian cancer cells to carboplatin. Lapatinib combined with carboplatin also significantly inhibits serous ovarian carcinoma growth compared with each drug alone in a xenograft mouse model. HECTD3 may be considered a promising molecular predictor of platinum chemosensitivity and prognosis for serous ovarian cancer. Through decreasing HECTD3, lapatinib possesses significantly increased anti-tumor activity when combined with carboplatin compared with each agent alone, which provides an optional therapeutic regimen for serous ovarian cancer.

Abstract 963: Ovarian-dependent SSM2ucd mouse mammary carcinoma cells depend on Cyp3a11 epoxygenase activity for proliferation

Abstract Introduction: Silencing of the human cytochrome P450 (CYP) monooxygenase enzyme CYP3A4 in the ER+ MCF-7 tumor cell line inhibits tumor growth in the mammary fat pad, but the relative roles of tumor cell intrinsic CYPs vs. vascular/microenvironment CYPs remain to be determined and a syngeneic animal model is needed to answer this question. The SSM2ucd ovarian dependent mouse mammary carcinoma cell line forms a transplantable estrogen-receptor positive (ER+) mouse mammary tumor in which growth dependence on cell intrinsic CYPs may be tested in vitro and in vivo. The SSM2ucd cell line is derived from 129SvJ: homozygous Stat1-null female mice, which develop ER+ mammary tumors (1,2). Expression profiling of spontaneously arising mouse mammary carcinomas in a TP53 KO model revealed that the CYP3A4 ortholog Cyp3a11 is up-regulated in these tumors. Methods: Cyp3a11 bactosomes were used to assay for NADPH dependent biosynthesis of EETs from arachidonic acid using an LC-MS/MS method. siRNA silencing and CRISPR/Cas9 knock out of the Cyp3a11 exons 2 and 3 was performed and the cell lines were characterized for EET dependence using an MTT assay. The highly potent inhibitor and chemical probe of CYP epoxygenase activity, hexyl-benzyl-biguanide (HBB), was used to test dependence of SSM2ucd cells on CYP epoxygenase activity. Total cellular EETs in SSM2ucd cells exposed to HBB at the IC50were measured by the LC-MS/MS method. Results: Cyp3a11 was shown to have robust NADPH dependent epoxygenase activity, while SSM2ucd cells were EET dependent for growth. Silencing of Cyp3a11 was demonstrated to inhibit proliferation of the SSM2ucd cell line, which was partly abrogated by EETs. CRISPR/Cas9 knock out of the Cyp3a11 in the SSM2ucd cell line was performed and exon 2 and exon 3 deleted cell lines were derived. SSM2ucd Cyp3a11 knock out cell lines were more sensitive to EET-induced proliferation under serum free condition than control lines. HBB potently inhibits the SSM2ucd cell line in vitro (IC50=25 uM) and reduces total cellular EET levels in this cell line at IC50. These results suggest that we may see inhibitory activity of HBB in a syngeneic 129/SvJ tumor transplantation model. Conclusions: The Cyp3a11 gene can be silenced in the SSM2ucd cell line, without disrupting cell viability, allowing further study of the roles of EETs in mouse mammary carcinoma proliferation, survival and clonogenicity. The Cyp3a11 gene has been knocked out in the SSM2 ucd cell line, allowing in vitro and in vivo studies of the roles of Cyp3a11 in the growth of ovarian dependent mouse mammary carcinoma. 1. Breast Cancer Res. 2012 Jan 20;14(1):R16 2. PLoS One. 2015 Jun 15;10(6):e0129895] Citation Format: Zhijun Guo, Patrick McGrarrah, Ted Bebi, Ashley Mooneyham, Alejandra Osorio, Cesar Herrera, Victor Arrieta, Sebastian Mohar, Irwin Hernandez, Robert Klink, Robert Cardiff, David A. Potter. Ovarian-dependent SSM2ucd mouse mammary carcinoma cells depend on Cyp3a11 epoxygenase activity for proliferation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 963. doi:10.1158/1538-7445.AM2017-963