Proliferation Of Ovarian Cancer Cell Lines Research Articles

Moringa oleifera compounds from seeds and extracts from leaves: anticancer and cancer chemopreventive properties; preparation of leaf extract-based herbal syrup

There is significant interest to use Moringa oleifera or “malunggay” as a source of anticancer and cancer chemopreventive agents to develop pharmaceutical drugs and herbal preparations. In this study, we isolated niazirin, niazinin, niazimicin, niaziminin and other glucosinolates, i.e., nitrile and O-thiocarbamate glycosides, from the ethanolic extract of M. oleifera seeds. These compounds were tested for antiproliferative activity in the MTT assay in human cancer cell lines, apoptotic activity in the annexin V/propidium iodide (PI) assay, antimigration activity in the matrigel wound healing assay, antiangiogenesis activity in the in ovo chorioallantoic membrane (CAM) assay, and activation of antioxidant response elements (ARE) in the ARE-luciferase reporter assay. The following activities were observed in the following compounds from seeds: antimigration and antiangionesis in niazirin; antimigration in niazinin; apoptosis, antimigration and antiangionesis in niazimicin; and antiproliferation and apoptosis in niaziminin. Several seed and leaf fractions activated ARE. We prepared a syrup formulation from an ethanolic leaf extract found to contain flavonoids, lipids and derivatives and a tetrapyrrole, which activated ARE and selectively inhibited SKOV-3 ovarian cancer cell line proliferation and showed no inhibition of the MDCK normal cell line.

Evidences for involvement of estrogen receptor induced ERK1/2 activation in ovarian cancer cell proliferation by Cadmium Chloride

Cadmium (Cd) as a human carcinogen and one of the most toxic industrial and environmental pollutant mimics the estrogenic effects in cell proliferation. So, it might have a role in the incidence and etiology of hormone-related cancers such as ovarian cancer as the most lethal gynecologic malignancy. This study aimed to evaluate the estrogenic effect and underlying mechanism of Cd in ovarian cancer cell line proliferation. OVCAR3 and SKOV3 cell lines were treated with different concentrations of CdCl2 (0- 50 μM). Cell proliferation was analyzed using MTT and BrdU assay. To evaluate the estrogenic effect of Cd, the cells were pre-incubated with estrogen receptor (ER) antagonist ICI 182,780. The expression of ER was determined using western blotting method. Real-time RT-PCR method was used to assess c-fos, c-jun and FOXO3a mRNA level. The results showed that Cd has an estrogenic proliferative effect at nM concentration range and ICI 182,780 significantly reversed the CdCl2-induced cell proliferation. Cd also increased the expression of ERs. Cd exposure induced activation of p-ERK1/2 in these cells. Cd also intensified c-jun, c-fos, and FOXO3a mRNA expression. Taken together, the current work suggests that Cd induces ovarian cancer cell proliferation in an ER-dependent mechanism induced ERK1/2 activation pathway. Understanding of downstream targets by which Cd deregulates cell proliferation can be noteworthy to define its underlying carcinogenesis mechanism.

Abstract 1209: Istiratumab (MM-141), a bispecific antibody targeting IGF-1R and ErbB3, inhibits pro-survival signaling in vitro and potentiates the activity of standard of care chemotherapy in vivo in ovarian cancer models

Abstract Insulin-like growth factor receptor 1 (IGF-1R) signaling has been implicated in the pathogenesis of ovarian cancer. However, clinical trials evaluating monospecific IGF-1R inhibitors have demonstrated limited clinical efficacy. Our data indicate that ErbB3, a member of the ErbB receptor tyrosine kinase family, can activate pro-survival AKT signaling in response to IGF-1R blockade and may represent a potential escape route in the development of resistance to therapy. Istiratumab (MM-141), an IGF-1R and ErbB3 directed bispecific antibody, inhibits ligand activation of these signaling pathways and degrades IGF-1R and ErbB3 receptor-containing complexes, leading to inhibition of downstream pro-survival signaling. Here we tested the activity of istiratumab, alone and in combination with chemotherapy, in in vitro and in vivo models of ovarian cancer. Anti-proliferative activity of istiratumab monotherapy was evaluated in a panel of ovarian cancer cell lines in vitro. The effects of istiratumab and the ligands IGF-1 and heregulin on IGF-1R- and ErbB3-mediated survival signaling were tested by ELISA and immunoblotting. Co-treatment assays with istiratumab and chemotherapy investigated mechanisms of synergy and additivity. Anti-tumor activity of istiratumab, alone and in combination with chemotherapy, was tested in in vivo ovarian xenograft tumor models. Our results indicated that istiratumab monotherapy inhibits ovarian cancer cell line proliferation in vitro. In addition, istiratumab blocked ligand-mediated resistance to chemotherapy. Co-treatment of istiratumab, ligands or chemotherapy indicated a strong correlation between drug activity and IGF-1R expression. Furthermore, co-treatment of chemotherapies and ligands potentiated AKT activation, which was inhibited by istiratumab. In vivo studies showed that istiratumab potentiates the activity of chemotherapy in ovarian xenograft tumor models. Our findings demonstrate that co-inhibition of IGF-1R and ErbB3 signaling with istiratumab can potentiate standard of care chemotherapies in ovarian tumor models and warrant further investigation of istiratumab as a potential therapy for ovarian cancer patients. Citation Format: Michael D. Curley, Gege Tan, Isabel Yannatos, Adam Camblin, Sergio Iadevaia, Chrystal Louis, Alexey Lugovskoy. Istiratumab (MM-141), a bispecific antibody targeting IGF-1R and ErbB3, inhibits pro-survival signaling in vitro and potentiates the activity of standard of care chemotherapy in vivo in ovarian cancer models. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1209.

Abstract 678: SOCS-1 inhibits proliferation of ovarian cancer cell lines by regulating JAK/STAT3 pathway and p53

Abstract [BACKGROUND]Ovarian cancer (OC) is a leading cause of the gynecological malignancy death in United States and many developed nations, and the number of OC patients is increasing. Patients with OC have poor prognosis because most OCs are detected at late stage and they often recur after chemotherapy with chemoresistance. So we need novel therapies for refractory OC. Recently, lines of evidence showed that constitutive activation of IL-6/JAK/STAT3 (signal transducers and activators of transcription 3) pathway is involved in proliferation of many kinds of cancer, including OC. SOCS (suppressor of cytokine signaling) families are known as negative regulators of JAK /STAT signal pathway. The aim of this study is to evaluate the effect of SOCS-1 in proliferation of OC and to develop a new therapy for intractable OC. [MATERIAL and METHOD]We overexpressed SOCS-1 in ten human OC cell lines (MCAS, OVISE, OVCAR-3, OVSAHO, OVTOKO, OVMANA, ES-2, A2780, SKOV-3, RMG-1) by infecting cells with adenovirus vector expressing SOCS-1. Adenovirus vector expressing LacZ was used as a control. Anti-proliferative effect of SOCS-1 in OC was assessed by WST-8 assay. Proteins related to apoptosis and other signal pathways were assessed by Western blot analysis. The interaction between SOCS-1 and p53 was examined by immunoprecipitation assays. [RESULT] Overexpression of SOCS-1 inhibited proliferation of 9 OC cell lines. Significantly enhanced apoptosis was observed in these cell lines. In most cell lines, STAT3 pathway was constitutively activated and was downregulated by SOCS-1 overexpression. However, growth inhibition by SOCS-1 was also observed in cell lines in which STAT3 activation at baseline was hardly detectable. Our screening analyses indicated that AKT, FAK and p44/p42 MAPK pathways were not affected by overexpression of SOCS-1. Finally, we found that in cell lines possessing wild type p53, overexpressed SOCS-1 associated with p53 and increased its protein levels. In contrast, JAK inhibitor failed to influence p53 expression. [Conclusion]SOCS-1 inhibited proliferation of OC cell lines by regulating JAK/STAT3 pathway and interacting with p53. SOCS-1 contributed to the enhancement of the stability and/or transcription activity of p53. In addition, signal pathways other than JAK/STAT3 and p53 pathways seemed to be regulated by SOCS-1. Now we analyze these unidentified signal pathways which may be regulated by SOCS-1 in OC. Citation Format: Satoshi Nakagawa, Satoshi Serada, Yusuke Takahashi, Yutaka Ueda, Minoru Fujimoto, Kiyoshi Yoshino, Takayuki Enomoto, Tadashi Kimura, Tetsuji Naka. SOCS-1 inhibits proliferation of ovarian cancer cell lines by regulating JAK/STAT3 pathway and p53. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 678. doi:10.1158/1538-7445.AM2015-678

Specific Thiazolidinediones Inhibit Ovarian Cancer Cell Line Proliferation and Cause Cell Cycle Arrest in a PPARγ Independent Manner

BackgroundPeroxisome Proliferator Activated Receptor gamma (PPARγ) agonists, such as the thiazolinediones (TZDs), have been studied for their potential use as cancer therapeutic agents. We investigated the effect of four TZDs—Rosiglitazone (Rosi), Ciglitazone (CGZ), Troglitazone (TGZ), and Pioglitazone (Pio)—on ovarian cancer cell proliferation, PPARγ expression and PPAR luciferase reporter activity. We explored whether TZDs act in a PPARγ dependent or independent manner by utilizing molecular approaches to inhibit or overexpress PPARγ activity.Principal FindingsTreatment with CGZ or TGZ for 24 hours decreased proliferation in three ovarian cancer cell lines, Ovcar3, CaOv3, and Skov3, whereas Rosi and Pio had no effect. This decrease in Ovcar3 cell proliferation was due to a higher fraction of cells in the G0/G1 stage of the cell cycle. CGZ and TGZ treatment increased apoptosis after 4 hours of treatment but not after 8 or 12 hours. Treatment with TGZ or CGZ increased PPARγ mRNA expression in Ovcar3 cells; however, protein levels were unchanged. Surprisingly, luciferase promoter assays revealed that none of the TZDs increased PPARγ activity. Overexpression of wild type PPARγ increased reporter activity. This was further augmented by TGZ, Rosi, and Pio indicating that these cells have the endogenous capacity to mediate PPARγ transactivation. To determine whether PPARγ mediates the TZD-induced decrease in proliferation, cells were treated with CGZ or TGZ in the absence or presence of a dominant negative (DN) or wild type overexpression PPARγ construct. Neither vector changed the TZD-mediated cell proliferation suggesting this effect of TZDs on ovarian cancer cells may be PPARγ independent.ConclusionsCGZ and TGZ cause a decrease in ovarian cancer cell proliferation that is PPARγ independent. This concept is supported by the finding that a DN or overexpression of the wild type PPARγ did not affect the changes in cell proliferation and cell cycle.