Expression and signaling of Toll-like receptor 4 (TLR4) and MyD88 in ovarian carcinoma cells

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e16508-e16508 ◽  
Author(s):  
M. E. Szajnik ◽  
M. J. Szczepanski ◽  
M. Czystowska ◽  
E. Elishaev ◽  
M. Mandapathil ◽  
...  

e16508 Background: TLR4, expressed by the cells of the immune system play a role in the protection of the host against pathogens. TLRs are also expressed on human cancer cells, but their role in tumor growth is unknown. The aim of this study was to correlate the presence of TLR4 and MyD88 expression with clinicopathologic outcome in patients with ovarian cancer and to analyze the consequences of signaling via the TLR4/MyD88 pathway in ovarian cancer cell lines. Methods: Tumor specimens from 41 patients with ovarian carcinoma were evaluated for TLR4 and MyD88 by immunohistochemistry and correlated with clinical and pathologic disease features. TLR4/MyD88 expression in OVCAR3, SKOV3, and A2780 was determined using RT-PCR, WB, and immunohistochemistry. NF-kB translocation to nucleus was measured by confocal microscopy. Culture supernatants were tested for levels of cytokines in Luminex-based assays. Proliferation of cancer cells was measured in the CFSE assays. Their sensitivity to paclitaxel (PLX) was measured by Annexin V binding. Western Blot analysis was used to measure activation of the PI3K/Akt, IRAK 1, IRAK 4, and TRIF. Results: In ovarian cancer patients TLR4 and MyD88 expression by the tumor was observed in 100% and 83% of tissues, respectively. The expression of MyD88 was associated with shorter progression-free survival (42 vs 31 months, p < 0.05). Ex vivo studies showed that TLR4 was expressed on OVCAR3, SKOV3, and A2780 cell lines, while A2780 did not expressed MyD88. In MyD88+ tumor cells, LPS increased proliferation (PI 17 vs 8, p < 0.05), activated NF-kB pathway and promoted cytokine production (IL-8, IL-6, RANTES, VEGF and MCP-1). LPS and PLX binding to TLR4 on MyD88+ cells induced activation of PI3K/Akt, IRAK4, and IRAK1, but decreased expression of pro-apoptotic TRIF. In contrast, in MyD88(-) cells LPS did not induce proliferation and neither LPS nor PLX induced secretion of pro-inflammatory cytokines. Further, no changes were noted in IRAK1 expression, but strong signal was observed for TRIF. TLR4+/MyD88+ tumor cells showed grater resistance to PLX. Conclusions: Our ex vivo studies elucidate the molecular mechanisms involved in TLR4/MyD88 signaling. Ligation via TLR4 leads to tumor growth, release of proinflammatory cytokines and induction of resistance to PLX-induced apoptosis. No significant financial relationships to disclose.

2006 ◽  
Vol 1 ◽  
pp. 117727190600100 ◽  
Author(s):  
Akiko Horiuchi ◽  
Cuiju Wang ◽  
Norihiko Kikuchi ◽  
Ryosuke Osada ◽  
Toshio Nikaido ◽  
...  

BRCA1 is a tumor suppressor which plays a crucial role in the repair of DNA double-strand breaks, and its abnormality is responsible for hereditary ovarian cancer syndrome. It has recently been reported that reduced expression of BRCA1 is also common in sporadic ovarian carcinoma via its promoter hypermethylation, and that ovarian carcinoma patients negative for BRCA1 expression showed favorable prognosis. To address if BRCA1 expression plays a role in the chemotherapeutic response, we analyzed the effect of BRCA1 suppression on the sensitivity to cisplatin and paclitaxel in ovarian cancer cells. Specific siRNA for BRCA1 gene was transfected into 3 ovarian cancer cell lines with various p53 status. Reduced expression of BRCA1 by transfection of BRCA1-siRNA resulted in a 5.3-fold increase in sensitivity to cisplatin in p53-wild A2780 cells, but not in p53-mutated A2780/CDDP and p53-deleted SKOV3 cells. Regarding the sensitivity to paclitaxel, BRCA1 suppression caused no significant changes in all the 3 cell lines. For ionizing radiation sensitivity, BRCA1 suppression also showed a significant higher sensitivity in A2780 cells. Growth curve and cell cycle analyses showed no significant differences between BRCA1-siRNA-transfected A2780 cells and control cells. However, cisplatin treatment under suppression of BRCA1 showed a significantly increased apoptosis along with up-regulation of p53 and p21 in A2780 cells. Accordingly, reduced expression of BRCA1 enhances the cisplatin sensitivity and apoptosis via up-regulation of p53 and p21, but does not affect the paclitaxel sensitivity. Expression of BRCA1 might be an important biomarker for cisplatin resistance in ovarian carcinoma.


2020 ◽  
Vol 40 (1) ◽  
Author(s):  
Nanumi Han ◽  
Delnur Anwar ◽  
Naoki Hama ◽  
Takuto Kobayashi ◽  
Hidefumi Suzuki ◽  
...  

Abstract Background Interleukin (IL)-34 acts as an alternative ligand for the colony-stimulating factor-1 receptor and controls the biology of myeloid cells, including survival, proliferation, and differentiation. IL-34 has been reported to be expressed in cancer cells and to promote tumor progression and metastasis of certain cancers via the promotion of angiogenesis and immunosuppressive macrophage differentiation. We have shown in our previous reports that targeting IL-34 in chemo-resistant tumors in vitro resulted in a remarkable inhibition of tumor growth. Also, we reported poor prognosis in patients with IL-34-expressing tumor. Therefore, blocking of IL-34 is considered as a promising therapeutic strategy to suppress tumor progression. However, the molecular mechanisms that control IL-34 production are still largely unknown. Methods IL-34 producing ovarian cancer cell line HM-1 was treated by bromodomain and extra terminal inhibitor JQ1. The mRNA and protein expression of IL-34 was evaluated after JQ1 treatment. Chromatin immunoprecipitation was performed to confirm the involvement of bromodomain-containing protein 4 (Brd4) in the regulation of the Il34 gene. Anti-tumor effect of JQ1 was evaluated in mouse tumor model. Results We identified Brd4 as one of the critical molecules that regulate Il34 expression in cancer cells. Consistent with this, we found that JQ1 is capable of efficiently suppressing the recruitment of Brd4 to the promotor region of Il34 gene. Additionally, JQ1 treatment of mice bearing IL-34-producing tumor inhibited the tumor growth along with decreasing Il34 expression in the tumor. Conclusion The results unveiled for the first time the responsible molecule Brd4 that regulates Il34 expression in cancer cells and suggested its possibility as a treatment target.


2011 ◽  
Vol 21 (2) ◽  
pp. 280-288 ◽  
Author(s):  
Chunjie Peng ◽  
Xiaolei Zhang ◽  
Hongli Yu ◽  
Donglai Wu ◽  
Jianhua Zheng

Introduction:Wnt5a regulates numerous signaling pathways controlling a wide range of cellular processes, including cell proliferation, differentiation, and apoptosis. However, it is still unclear whether Wnt5a is involved in mediating chemoresistance in cancer. We studied the correlation of Wnt5a expression with clinicopathologic parameters and survival in epithelial ovarian cancer and the effect of Wnt5a expression on chemoresistance of ovarian cancer cells.Methods:Wnt5a expression was immunohistochemically examined in ovarian cancer, benign tumor, and normal ovarian tissues. Two stable cell lines were established, namely, SKOV3/Wnt5a, which overexpressed Wnt5a, and SKOV3/miRNA, which downregulated Wnt5a expression using microRNA (miRNA). Wnt5a expression level was evaluated by semiquantitative reverse transcription-polymerase chain reaction, Western blot analysis, and immunofluorescence assay. The sensitivity of all transfected and untransfected cell lines to chemotherapeutic drugs (paclitaxel, oxaliplatin, 5-fluorouracil, epirubicin, and etoposide) was detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay.Results:Wnt5a was found to be significantly higher in ovarian cancer compared with benign tumors and normal ovaries. High levels of Wnt5a expression were associated with the International Federation of Gynecology and Obstetrics stage and significantly predicted a poorer overall survival and progression-free survival compared with low Wnt5a expression. In addition, Wnt5a overexpression in SKOV3/Wnt5a cells decreased chemosensitivity compared with normal and empty vector controls (P < 0.05). Alternatively, Wnt5a down-regulation in SKOV3/miRNA cells led to a significant increase in chemosensitivity (P < 0.05).Conclusions:Wnt5a immunoreactivity may be a useful prognostic indicator in patients with ovarian cancer. These results clarified for the first time the possibility that Wnt5a plays an important role in regulating chemosensitivity to anticancer drugs in ovarian cancer cells.


Cancers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1369
Author(s):  
Mikhail S. Chesnokov ◽  
Imran Khan ◽  
Yeonjung Park ◽  
Jessica Ezell ◽  
Geeta Mehta ◽  
...  

High-grade serous ovarian carcinoma (HGSOC) is the deadliest of gynecological cancers due to its high recurrence rate and acquired chemoresistance. RAS/MEK/ERK pathway activation is linked to cell proliferation and therapeutic resistance, but the role of MEK1/2-ERK1/2 pathway in HGSOC is poorly investigated. We evaluated MEK1/2 pathway activity in clinical HGSOC samples and ovarian cancer cell lines using immunohistochemistry, immunoblotting, and RT-qPCR. HGSOC cell lines were used to assess immediate and lasting effects of MEK1/2 inhibition with trametinib in vitro. Trametinib effect on tumor growth in vivo was investigated using mouse xenografts. MEK1/2 pathway is hyperactivated in HGSOC and is further stimulated by cisplatin treatment. Trametinib treatment causes cell cycle arrest in G1/0-phase and reduces tumor growth rate in vivo but does not induce cell death or reduce fraction of CD133+ stem-like cells, while increasing expression of stemness-associated genes instead. Transient trametinib treatment causes long-term increase in a subpopulation of cells with high aldehyde dehydrogenase (ALDH)1 activity that can survive and grow in non-adherent conditions. We conclude that MEK1/2 inhibition may be a promising approach to suppress ovarian cancer growth as a maintenance therapy. Promotion of stem-like properties upon MEK1/2 inhibition suggests a possible mechanism of resistance, so a combination with CSC-targeting drugs should be considered.


Biomedicines ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 871
Author(s):  
Giulia Gorini ◽  
Francesca Magherini ◽  
Tania Fiaschi ◽  
Lara Massai ◽  
Matteo Becatti ◽  
...  

Au2phen ((2,9-dimethyl-1,10-phenanthroline)2Au2(µ-O)2)(PF6)2 and Auoxo6 ((6,6′-dimethyl-2,2′-bipyridine)2Au2(µ-O)2)(PF6)2 are two structurally related gold(III) complexes that were previously reported to display relevant and promising anticancer properties in vitro toward a large number of human cancer cell lines. To expand the knowledge on the molecular mechanisms through which these gold(III) complexes trigger apoptosis in cancer cells, further studies have been performed using A2780 ovarian cancer cells as reference models. For comparative purposes, parallel studies were carried out on the gold(III) complex AuL12 (dibromo(ethylsarcosinedithiocarbamate)gold(III)), whose proapoptotic profile had been earlier characterized in several cancer cell lines. Our results pointed out that all these gold(III) compounds manifest a significant degree of similarity in their cellular and proapoptotic effects; the main observed perturbations consist of potent thioredoxin reductase inhibition, disruption of the cell redox balance, impairment of the mitochondrial membrane potential, and induction of associated metabolic changes. In addition, evidence was gained of the remarkable contribution of ASK1 (apoptosis-signal-regulating kinase-1) and AKT pathways to gold(III)-induced apoptotic signaling. Overall, the observed effects may be traced back to gold(III) reduction and subsequent formation and release of gold(I) species that are able to bind and inhibit several enzymes responsible for the intracellular redox homeostasis, in particular the selenoenzyme thioredoxin reductase.


Blood ◽  
2003 ◽  
Vol 102 (1) ◽  
pp. 377-387 ◽  
Author(s):  
Chandini M. Thirukkumaran ◽  
Joanne M. Luider ◽  
Douglas A. Stewart ◽  
Tina Cheng ◽  
Sasha M. Lupichuk ◽  
...  

Abstract Hematologic stem cell rescue after high-dose cytotoxic therapy is extensively used for the treatment of many hematopoietic and solid cancers. Gene marking studies suggest that occult tumor cells within the autograft may contribute to clinical relapse. To date purging of autografts contaminated with cancer cells has been unsuccessful. The selective oncolytic property of reovirus against myriad malignant histologies in in vitro, in vivo, and ex vivo systems has been previously demonstrated. In the present study we have shown that reovirus can successfully purge cancer cells within autografts. Human monocytic and myeloma cell lines as well as enriched ex vivo lymphoma, myeloma, and Waldenström macroglobulinemia patient tumor specimens were used in an experimental purging model. Viability of the cell lines or purified ex vivo tumor cells of diffuse large B-cell lymphoma, chronic lymphocytic leukemia, Waldenström macroglobulinemia, and small lymphocytic lymphoma was significantly reduced after reovirus treatment. Further, [35S]-methionine labeling and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of cellular proteins demonstrated reovirus protein synthesis and disruption of host cell protein synthesis as early as 24 hours. Admixtures of apheresis product with the abovementioned tumor cells and cell lines treated with reovirus showed complete purging of disease. In contrast, reovirus purging of enriched ex vivo multiple myeloma, Burkitt lymphoma, and follicular lymphoma was incomplete. The oncolytic action of reovirus did not affect CD34+ stem cells or their long-term colony-forming assays even after granulocyte colony-stimulating factor (G-CSF) stimulation. Our results indicate the ex vivo use of an unattenuated oncolytic virus as an attractive purging strategy for autologous stem cell transplantations. (Blood. 2003;102:377-387)


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Maëva Chauvin ◽  
Véronique Garambois ◽  
Pierre-Emmanuel Colombo ◽  
Myriam Chentouf ◽  
Laurent Gros ◽  
...  

AbstractIn ovarian carcinoma, anti-Müllerian hormone (AMH) type II receptor (AMHRII) and the AMH/AMHRII signaling pathway are potential therapeutic targets. Here, AMH dose-dependent effect on signaling and proliferation was analyzed in four ovarian cancer cell lines, including sex cord stromal/granulosa cell tumors and high grade serous adenocarcinomas (COV434-AMHRII, SKOV3-AMHRII, OVCAR8 and KGN). As previously shown, incubation with exogenous AMH at concentrations above the physiological range (12.5–25 nM) decreased cell viability. Conversely, physiological concentrations of endogenous AMH improved cancer cell viability. Partial AMH depletion by siRNAs was sufficient to reduce cell viability in all four cell lines, by 20% (OVCAR8 cells) to 40% (COV434-AMHRII cells). In the presence of AMH concentrations within the physiological range (5 to 15 pM), the newly developed anti-AMH B10 antibody decreased by 25% (OVCAR8) to 50% (KGN) cell viability at concentrations ranging between 3 and 333 nM. At 70 nM, B10 reduced clonogenic survival by 57.5%, 57.1%, 64.7% and 37.5% in COV434-AMHRII, SKOV3-AMHRII, OVCAR8 and KGN cells, respectively. In the four cell lines, B10 reduced AKT phosphorylation, and increased PARP and caspase 3 cleavage. These results were confirmed in ovarian cancer cells isolated from patients’ ascites, demonstrating the translational potential of these results. Furthermore, B10 reduced COV434-MISRII tumor growth in vivo and significantly enhanced the median survival time compared with vehicle (69 vs 60 days; p = 0.0173). Our data provide evidence for a novel pro-survival autocrine role of AMH in the context of ovarian cancer, which was targeted therapeutically using an anti-AMH antibody to successfully repress tumor growth.


2019 ◽  
Author(s):  
Mikhail Chesnokov ◽  
Imran Khan ◽  
Yeonjung Park ◽  
Jessica Ezel ◽  
Geeta Mehta ◽  
...  

AbstractRationaleHigh-grade serous ovarian carcinoma (HGSOC) is the deadliest of gynecological cancers due to high rate of recurrence and acquired chemoresistance. Mutation and activation of the RAS/MAPK pathway has been linked to cancer cell proliferation and therapeutic resistance in numerous cancers. While RAS mutations are not commonly observed in HGSOC, less is known about downstream pathway activation. We therefore sought to investigate the role of MEK1/2 signaling in ovarian cancer.MethodsMEK1/2 pathway activity was evaluated in clinical HGSOC tissue samples and ovarian cancer cell lines by using tissue microarray-based immunohistochemistry, immunoblotting, and RT-qPCR. OVCAR8 and PEO4 HGSOC cell lines were used to assess the effect of MEK1/2 inhibition on cell viability, proliferation rate, and stem-like characteristics. Xenografts were used in mice to investigate the effect of MEK1/2 inhibition on tumor growth in vivo. A drug washout experimental model was used to study the lasting effects of MEK1/2 inhibition therapy.ResultsMEK1/2 signaling is active in a majority of HGSOC tissue samples and cell lines. MEK1/2 is further stimulated by cisplatin treatment, suggesting that MEK1/2 activation may play a role in chemotherapy resistance. The MEK1/2 inhibitor, trametinib, drastically inhibits MEK1/2 downstream signaling activity, causes prominent cell cycle arrest in the G1/0-phase in cell cultures, and reduces the rate of tumor growth in vivo, but does not induce cell death. Cells treated with trametinib display a high CD133+ fraction and increased expression of stemness-associated genes. Transient trametinib treatment causes long-term increases in a high ALDH1 activity subpopulation of cells that possess the capability of surviving and growing in non-adherent conditions.ConclusionsMEK1/2 inhibition in HGSOC cells efficiently inhibits proliferation and tumor growth and therefore may be a promising approach to suppress ovarian cancer cell growth. MEK1/2 inhibition promotes stem-like properties, thus suggesting a possible mechanism of resistance and that a combination with CSC-targeting drugs should be considered.


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