scholarly journals Hypoxia-induced up-regulation of miR-27a promotes paclitaxel resistance in ovarian cancer

2020 ◽  
Vol 40 (4) ◽  
Author(s):  
Lanlan Feng ◽  
Fangrong Shen ◽  
Jinhua Zhou ◽  
Yan Li ◽  
Rong Jiang ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Regulatory Mechanism ◽  
Chemotherapy Resistance ◽  
Paclitaxel Resistance ◽  
In Vivo Experiments ◽  
Hypoxic Environment ◽  
Skov3 Cells

Abstract Ovarian cancer (OC) is a malignant tumor with high mortality in women. Although cancer patients initially respond to paclitaxel chemotherapy following surgery, most patients will relapse after 12–24 months and gradually die from chemotherapy resistance. In OC, cancer cells become resistant to paclitaxel chemotherapy under hypoxic environment. The miR-27a has been identified as an oncogenic molecular in ovarian cancer, prostate cancer, liver cancer etc. In addition, the miR-27a is involved in hypoxia-induced chemoresistance in various cancers. However, the role of miR-27a in hypoxia-induced OC resistance remains unclear. The aim of the present study was to investigate the regulatory mechanism of miR-27a in hypoxia-induced OC resistance. The expression of HIF-1α induced Hypoxia overtly up-regulated. At the same time, hypoxia increased viability of Skov3 cells and decreased cell apoptosis when treated with paclitaxel. The expression of the miR-27a was obviously up-regulated under hypoxia and involved in hypoxia-induced paclitaxel resistance. Follow-up experiments portray that miR-27a improved paclitaxel resistance by restraining the expression of APAF1 in OC. Finally, we further elucidated the important regulatory role of the miR-27a-APAF1 axis in OC through in vivo experiments. According to our knowledge, we first reported the regulation of miR-27a in hypoxia-induced chemoresistance in OC, providing a possible target for chemoresistance treatment of OC.

scholarly journals Characterization of SOX2, OCT4 and NANOG in Ovarian Cancer Tumor-Initiating Cells

Cancers ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 262
Author(s):  
Mikella Robinson ◽  
Samuel F. Gilbert ◽  
Jennifer A. Waters ◽  
Omar Lujano-Olazaba ◽  
Jacqueline Lara ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Chemotherapy Resistance ◽  
Tumor Initiating Cells ◽  
In Vivo Experiments ◽  
Nanog Expression ◽  
Ovarian Cancer Cell Lines ◽  
Cancer Tumor ◽  
Early Tumor ◽  
Cycle Regulation

The identification of tumor-initiating cells (TICs) has traditionally relied on surface markers including CD133, CD44, CD117, and the aldehyde dehydrogenase (ALDH) enzyme, which have diverse expression across samples. A more reliable indication of TICs may include the expression of embryonic transcription factors that support long-term self-renewal, multipotency, and quiescence. We hypothesize that SOX2, OCT4, and NANOG will be enriched in ovarian TICs and may indicate TICs with high relapse potential. We evaluated a panel of eight ovarian cancer cell lines grown in standard 2-D culture or in spheroid-enriching 3-D culture, and correlated expression with growth characteristics, TIC marker expression, and chemotherapy resistance. RNA-sequencing showed that cell cycle regulation pathways involving SOX2 were elevated in 3-D conditions. HGSOC lines had longer doubling-times, greater chemoresistance, and significantly increased expression of SOX2, OCT4, and NANOG in 3-D conditions. CD117+ or ALDH+/CD133+ cells had increased SOX2, OCT4, and NANOG expression. Limiting dilution in in vivo experiments implicated SOX2, but not OCT4 or NANOG, with early tumor-initiation. An analysis of patient data suggested a stronger role for SOX2, relative to OCT4 or NANOG, for tumor relapse potential. Overall, our findings suggest that SOX2 may be a more consistent indicator of ovarian TICs that contribute to tumor repopulation following chemotherapy. Future studies evaluating SOX2 in TIC biology will increase our understanding of the mechanisms that drive ovarian cancer relapse.

scholarly journals Hedgehog−Gli2 Signaling Promotes Chemoresistance in Ovarian Cancer Cells by Regulating MDR1

2022 ◽  
Vol 11 ◽  
Author(s):  
Qian Wang ◽  
Xin Wei ◽  
Lanyan Hu ◽  
Lingling Zhuang ◽  
Hong Zhang ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Nude Mice ◽  
Chemotherapy Resistance ◽  
Cell Counting ◽  
Luciferase Reporter ◽  
Ovarian Cancer Cells ◽  
Luciferase Reporter Gene ◽  
Downstream Target ◽  
Skov3 Cells

BackgroundCisplatin (DDP) resistance remains a key challenge in improving the clinical outcome of patients with ovarian cancer (OC). Gli2 overexpression can lead to DDP resistance in OC cells, but the specific underlying regulatory mechanism remains unclear. The membrane transporter encoding gene MDR1 positively regulates chemotherapy resistance in various cancer types. We evaluated MDR1 as a potential Gli2 downstream target and the contribution of the Gli2/MDR1 axis in promoting DDP resistance in OC cells.MethodsTo generate drug-resistant SKOV3/DDP cells, SKOV3 cells were grown for six months under continuous induction wherein the DDP concentration was steadily increased. Gli2 expression in OC cells with varying DDP sensitivities was detected using western blot. Cell counting kit-8 assays were used to assess the DDP sensitivity of SKOV3, SKOV3/DDP, A2780, and A2780/DDP cells and reversal of DDP resistance in SKOV3/DDP and A2780/DDP cells. Cell proliferation was analyzed using 5-ethynyl-2′-deoxyuridine (EdU) incorporation assays. The transcriptional regulation of MDR1 by Gli2 was determined using luciferase reporter assays. Finally, xenograft OC tumors were generated in nude mice, which were then treated with intraperitoneal DDP or phosphate-buffered saline (PBS) injections to investigate if Gli2 affected DDP resistance in OC in vivo.ResultsDDP-resistant SKOV3/DDP and A2780/DDP cells showed higher expression of Gli2 and MDR1 as compared with that in DDP-sensitive OC cells. Gli2 knockdown in SKOV3/DDP cells significantly reduced MDR1 expression, whereas it increased DNA damage, thereby sensitizing OC cells to DDP. Similar results were obtained after targeting Gli2 expression with the Gli-antagonist 61 inhibitor (GANT61) in SKOV3/DDP and A2780/DDP cells. In cells stably overexpressing Gli2, treatment with gradient concentrations of verapamil, an MDR1 inhibitor, significantly inhibited MDR1 expression. Our findings indicate that downregulation of MDR1 expression may reverse OC cell resistance to DDP. Moreover, dual-luciferase reporter gene assays confirmed that MDR1 is a direct downstream target of Gli2, with Gli2 positively regulating MDR1 expression. Finally, subcutaneous xenotransplantation in nude mice demonstrated that Gli2 plays a key role in regulating OC drug resistance.ConclusionsWe identified a mechanism by which Hedgehog-Gli signaling regulates OC chemoresistance by modulating MDR1 expression. Hence, Gli2 and MDR1 are potential biomarkers and therapeutic targets in patients with chemoresistant OC.

scholarly journals Long Noncoding RNA E2F4as Promotes Progression and Predicts Patient Prognosis in Human Ovarian Cancer

Cancers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3626
Author(s):  
Sun-Ae Park ◽  
Lee Kyung Kim ◽  
Young Tae Kim ◽  
Tae-Hwe Heo ◽  
Hee Jung Kim
Keyword(s):  
Ovarian Cancer ◽  
Cell Proliferation ◽  
Cancer Cells ◽  
Noncoding Rna ◽  
Ovarian Cancer Cells ◽  
Serum Samples ◽  
Invasion And Migration ◽  
In Vivo Experiments

(1) Background: LncRNAs could be a promising biomarker to predict the prognosis of various cancers. The significance of E2F4antisense lncRNA remains unclear in cancer. In this study, we examined the expression level of E2F4as in the serum of ovarian cancer patients and the functional role of E2F4as. (2) Methods: Serum samples were obtained from 108 OC patients and 32 normal patients to measure the expression of E2F4as in the serum. Ovarian cancer cells were used to investigate the role of E2F4as in cell proliferation, invasion, migration and apoptosis, and the expression of E2F4as was knocked down using RNA interference. In addition, E2F4as knockdown cell lines were used in in vivo experiments. (3) Results: The expression of E2F4as was significantly higher in the serum of OC patients than in that of control patients (p < 0.05). The knockdown of E2F4as in ovarian cancer cells led to a decrease in cell proliferation, invasion and migration and an increase in apoptosis. E2F4as knockdown also reduced the expression of epithelium–mesenchymal metastasis (EMT) genes. (4) Conclusion: These findings highlight the clinical significance of E2F4as in predicting the prognosis of OC patients and suggest its potential in promoting tumour aggressiveness by the regulation of EMT-related mechanisms.

scholarly journals Down-regulation of PADI2 prevents proliferation and epithelial-mesenchymal transition in ovarian cancer through inhibiting JAK2/STAT3 pathway in vitro and in vivo, alone or in combination with Olaparib

2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Lidong Liu ◽  
Zhiwei Zhang ◽  
Guoxiang Zhang ◽  
Ting Wang ◽  
Yingchun Ma ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Combination Treatment ◽  
Migration And Invasion ◽  
Link Type ◽  
Stat3 Signaling ◽  
Stat3 Signaling Pathway ◽  
Skov3 Cells

Abstract Background Epithelial ovarian cancer (EOC) is the most lethal disease among female genital malignant tumors. Peptidylarginine deiminase type II(PADI II) has been shown to enhance a variety of cancers carcinogenesis, including ovarian cancer. The purpose of this study was to investigate the biological role of PADI2 in ovarian cancer (OC) and the relative mechanism. Methods Gene Expression Profiling Interactive Analysis (GEPIA) (https://gepia.pku.cn/) and ONCOMINE (https://www.oncomine.org/) were used to analyze PADI2 Gene Expression data. The survival curve for the PADI2 gene was generated by using the online Kaplan–Meier mapping site (https://www.kmplot.com/). We conducted MTT assay, cloning formation assay and EdU cell proliferation assay to detect the cell activity of PADI2 knockdown A2780 and SKOV3 ovarian cancer cells treated with Olaparib. Cell migration and invasion were observed by would healing and transwell assay. The pathway changes after the treatment of PADI2 were detected by transcriptome sequencing and western blot. The role of PADI2 combined with Olaparib treatment in vivo was studied in nude mouse model bearing ovarian cancer tumor. Results We investigated the role of PADI2 on EOC in vitro and in vivo. PADI2 was upregulated in ovarian cancer samples and high PADI2 expression was correlated with poor outcome. Downregulating PADI2 suppressed colony formation, proliferation, migration and invasion of A2780 and SKOV3 cells. Furthermore, downregulating PADI2 and Olaparib combination treatment attenuated the viability, migration and invasion of A2780 and SKOV3 cells. We identified differentially expressed genes in A2780-shPADI2 and SKOV3-shPADI2 cell by transcriptome sequencing analysis and verified that downregulating PADI2 and Olaparib combination treatment suppresses EMT and JAK2/STAT3 signaling pathway in A2780 and SKOV3 cells in vitro and in vivo. Conclusions Downregulation of PADI2 and Olaparib combination treatment attenuated the proliferation, migration and invasion of A2780 and SKOV3 cells by inhibiting the EMT through JAK2/STAT3 signaling pathway.

Role of CD10 expression in endometriosis-associated mesenchymal stem cells on the progression of endometriosis-associated carcinoma.

2021 ◽  
Vol 39 (15_suppl) ◽  
pp. 5561-5561
Author(s):  
Huda Atiya ◽  
Taylor Orellana ◽  
Lan Gardner Coffman
Keyword(s):  
Ovarian Cancer ◽  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Cell Growth ◽  
Tumor Cell ◽  
Chemotherapy Resistance ◽  
Cd10 Expression ◽  
Sphere Formation

5561 Background: Endometriosis-associated carcinomas (EACs) such as ovarian clear cell cancer (OCCC) are rare, aggressive, chemo-resistant malignancies. While endometriosis is a known chronic inflammatory condition, the molecular mechanisms for the malignant transformation of endometriosis is unknown. Mesenchymal stem cells (MSC) are a critical component of the ovarian cancer microenvironment. Cancer cells reprogram MSCs to form carcinoma-associated MSCs (CAMSCs), which promote cancer growth, chemotherapy resistance, and metastases. MSCs are also found within the endometriotic microenvironment. CD10, a surface protein expressed by endometrial stromal cells, is also expressed on endometriosis-associated MSCs (enMSCs). Preliminary data demonstrate CD10 expression is lost in a subset of enMSCs and this loss is correlated with the acquisition of tumor-promoting properties. We hypothesized that the CD10 negative subset of enMSCs behave similarly to CAMSCs and support the growth of OCCC. Methods: EnMSCs were isolated from primary human benign endometriosis deposits involving the ovary or fallopian tubes. Flow cytometry was used to measure surface CD10 expression. We investigated the role of low CD10 enMSCs versus high CD10 enMSCs on OCCC tumor cell growth, chemotherapy resistance and stem-like cell properties in vitro and tumor cell engraftment, growth, and metastases in vivo. Luciferase-expressing OCCC cells were (1) used alone, (2) mixed with low CD10 enMSCs, or (3) mixed with high CD10 enMSCs and injected orthotopically into the ovarian bursa of NSG mice. In vivo imaging system was used to follow tumor progression and metastasis. Results: Our results demonstrated that enMSCs have variable CD10 expression. EnMSCs with low CD10 expression significantly enhanced OCCC proliferation, resistance to cisplatin, and sphere formation compared to OCCC alone. In contrast, high CD10 expressing enMSCs significantly reduce OCCC proliferation and sphere formation. Interestingly, low CD10 enMSCs selectively enhanced OCCC cell growth and had no effect on high grade serious ovarian cancer cell growth. Moreover, a reduction of CD10 expression was observed over time when high CD10 enMSCs were co-cultured with OCCC cells. Our results also showed enhanced tumor engraftment when OCCC cells were co-injected with low CD10 enMSCs to 100% one week post-injection, compared to 40% with OCCC and high CD10 enMSCs and 60% with OCCC alone. Further, mice co-injected with low CD10 enMSCs demonstrated increased metastasis and decreased survival compared to mice co-injected with high CD10 enMSCs. Conclusions: Our results indicate there is a sub population of enMSCs, marked by decreased CD10 expression, which selectively enhances OCCC growth. This highlights the existence of a tumor-promoting stromal cell within endometriosis which may be critical to the formation and propagation of EACs.

scholarly journals Cancer-associated fibroblast-secreted exosomal miR-423-5p promotes chemotherapy resistance in prostate cancer by targeting GREM2 through the TGF-β signaling pathway

2020 ◽  
Vol 52 (11) ◽  
pp. 1809-1822
Author(s):  
Guang Shan ◽  
Juan Gu ◽  
Daoping Zhou ◽  
Lingxun Li ◽  
Wei Cheng ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Drug Resistance ◽  
Drug Sensitivity ◽  
Regulatory Mechanism ◽  
Chemotherapy Resistance ◽  
Drug Resistant ◽  
Cancer Associated Fibroblast ◽  
Pathway Inhibition

AbstractTherapeutic failure in prostate cancer (PC) is believed to result from its unusually invasive and metastatic nature. Cancer-associated fibroblasts (CAFs) are essential in the tumor microenvironment. We intended to study the role of CAF-derived exosomes in the context of PC and the potential regulatory mechanism associated with miR-423-5p and GREM2. CAF-derived exosomes decreased the chemosensitivity of parental PC cells and enhanced the drug resistance of drug-resistant cells. PC-associated fibroblast-derived exosomes carrying miR-423-5p increased the resistance of PC to taxane by inhibiting GREM2 through the TGF-β pathway. Inhibition of the TGF-β pathway partially reversed the increased drug resistance in PC cells induced by CAF-derived exosomes. Inhibition of miR-423-5p enhanced the drug sensitivity of PC cells in vivo. We showed that CAF-secreted exosomal miR-423-5p promoted chemotherapy resistance in PC by targeting GREM2 through the TGF-β pathway. This study may allow the development of novel approaches for PC.

scholarly journals Group III phospholipase A2 downregulation attenuated survival and metastasis in ovarian cancer and promotes chemo-sensitization

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Upasana Ray ◽  
Debarshi Roy ◽  
Ling Jin ◽  
Prabhu Thirusangu ◽  
Julie Staub ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Cell Viability ◽  
Phospholipase A2 ◽  
Mtt Assay ◽  
Metabolic Inhibitor ◽  
Autophagic Flux ◽  
Ciliated Cells ◽  
Group Iii

Abstract Background Aberrant lipogenicity and deregulated autophagy are common in most advanced human cancer and therapeutic strategies to exploit these pathways are currently under consideration. Group III Phospholipase A2 (sPLA2-III/PLA2G3), an atypical secretory PLA2, is recognized as a regulator of lipid metabolism associated with oncogenesis. Though recent studies reveal that high PLA2G3 expression significantly correlates with poor prognosis in several cancers, however, role of PLA2G3 in ovarian cancer (OC) pathogenesis is still undetermined. Methods CRISPR-Cas9 and shRNA mediated knockout and knockdown of PLA2G3 in OC cells were used to evaluate lipid droplet (LD) biogenesis by confocal and Transmission electron microscopy analysis, and the cell viability and sensitization of the cells to platinum-mediated cytotoxicity by MTT assay. Regulation of primary ciliation by PLA2G3 downregulation both genetically and by metabolic inhibitor PFK-158 induced autophagy was assessed by immunofluorescence-based confocal analysis and immunoblot. Transient transfection with GFP-RFP-LC3B and confocal analysis was used to assess the autophagic flux in OC cells. PLA2G3 knockout OVCAR5 xenograft in combination with carboplatin on tumor growth and metastasis was assessed in vivo. Efficacy of PFK158 alone and with platinum drugs was determined in patient-derived primary ascites cultures expressing PLA2G3 by MTT assay and immunoblot analysis. Results Downregulation of PLA2G3 in OVCAR8 and 5 cells inhibited LD biogenesis, decreased growth and sensitized cells to platinum drug mediated cytotoxicity in vitro and in in vivo OVCAR5 xenograft. PLA2G3 knockdown in HeyA8MDR-resistant cells showed sensitivity to carboplatin treatment. We found that both PFK158 inhibitor-mediated and genetic downregulation of PLA2G3 resulted in increased number of percent ciliated cells and inhibited cancer progression. Mechanistically, we found that PFK158-induced autophagy targeted PLA2G3 to restore primary cilia in OC cells. Of clinical relevance, PFK158 also induces percent ciliated cells in human-derived primary ascites cells and reduces cell viability with sensitization to chemotherapy. Conclusions Taken together, our study for the first time emphasizes the role of PLA2G3 in regulating the OC metastasis. This study further suggests the therapeutic potential of targeting phospholipases and/or restoration of PC for future OC treatment and the critical role of PLA2G3 in regulating ciliary function by coordinating interface between lipogenesis and metastasis.

scholarly journals The Extracellular Small Leucine-Rich Proteoglycan Biglycan Is a Key Player in Gastric Cancer Aggressiveness

Cancers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1330
Author(s):  
Filipe Pinto ◽  
Liliana Santos-Ferreira ◽  
Marta T. Pinto ◽  
Catarina Gomes ◽  
Celso A. Reis
Keyword(s):  
Clinical Value ◽  
Knock Out ◽  
Angiogenic Potential ◽  
In Vivo Experiments ◽  
Cancer Aggressiveness ◽  
Advanced Stages ◽  
Oncogenic Gene

Biglycan (BGN gene), an extracellular proteoglycan, has been described to be associated with cancer aggressiveness. The purpose of this study was to clarify the clinical value of biglycan as a biomarker in multiple independent GC cohorts and determine the in vitro and in vivo role of biglycan in GC malignant features. We found that BGN is commonly over-expressed in all analyzed cohorts, being associated with disease relapse and poor prognosis in patients with advanced stages of disease. In vitro and in vivo experiments demonstrated that biglycan knock-out GC cells display major phenotypic changes with a lower cell survival, migration, and angiogenic potential when compared with biglycan expressing cells. Biglycan KO GC cells present increased levels of PARP1 and caspase-3 cleavage and a decreased expression of mesenchymal markers. Importantly, biglycan deficient GC cells that were supplemented with exogenous biglycan were able to restore biological features, such as survival, clonogenic and migratory capacities. Our in vitro and in vivo findings were validated in human GC samples, where BGN expression was associated with several oncogenic gene signatures that were associated with apoptosis, cell migration, invasion, and angiogenesis. This study provided new insights on biglycan role in GC that should be taken in consideration as a key cellular regulator with major impact in tumor progression and patients’ clinical outcome.

Paradoxical effect of salbutamol in a model of acute organophosphates intoxication in guinea pigs: role of substance P release

2007 ◽  
Vol 292 (4) ◽  
pp. L915-L923 ◽  
Author(s):  
Jaime Chávez ◽  
Patricia Segura ◽  
Mario H. Vargas ◽  
José Luis Arreola ◽  
Edgar Flores-Soto ◽  
...  
Keyword(s):  
Substance P ◽  
Guinea Pigs ◽  
Smooth Muscle Contraction ◽  
In Vivo Experiments ◽  
Intracellular Ca ◽  
Neurokinin 1 ◽  
Substance P Release

Organophosphates induce bronchoobstruction in guinea pigs, and salbutamol only transiently reverses this effect, suggesting that it triggers additional obstructive mechanisms. To further explore this phenomenon, in vivo (barometric plethysmography) and in vitro (organ baths, including ACh and substance P concentration measurement by HPLC and immunoassay, respectively; intracellular Ca2+ measurement in single myocytes) experiments were performed. In in vivo experiments, parathion caused a progressive bronchoobstruction until a plateau was reached. Administration of salbutamol during this plateau decreased bronchoobstruction up to 22% in the first 5 min, but thereafter airway obstruction rose again as to reach the same intensity as before salbutamol. Aminophylline caused a sustained decrement (71%) of the parathion-induced bronchoobstruction. In in vitro studies, paraoxon produced a sustained contraction of tracheal rings, which was fully blocked by atropine but not by TTX, ω-conotoxin (CTX), or epithelium removal. During the paraoxon-induced contraction, salbutamol caused a temporary relaxation of ∼50%, followed by a partial recontraction. This paradoxical recontraction was avoided by the M2- or neurokinin-1 (NK1)-receptor antagonists (methoctramine or AF-DX 116, and L-732138, respectively), accompanied by a long-lasting relaxation. Forskolin caused full relaxation of the paraoxon response. Substance P and, to a lesser extent, ACh released from tracheal rings during 60-min incubation with paraoxon or physostigmine, respectively, were significantly increased when salbutamol was administered in the second half of this period. In myocytes, paraoxon did not produce any change in the intracellular Ca2+ basal levels. Our results suggested that: 1) organophosphates caused smooth muscle contraction by accumulation of ACh released through a TTX- and CTX-resistant mechanism; 2) during such contraction, salbutamol relaxation is functionally antagonized by the stimulation of M2 receptors; and 3) after this transient salbutamol-induced relaxation, a paradoxical contraction ensues due to the subsequent release of substance P.

Sign in / Sign up

Export Citation Format

Share Document