Activity In Ovarian Cancer Cells Research Articles

Lysine demethylase 3A in hypoxic macrophages promotes ovarian cancer development through regulation of the vascular endothelial growth factor A/Akt signaling

BackgroundHypoxia is a vital feature of the tumor microenvironment of OC. Previous evidence exposes that tumor-associated macrophages (TAMs) are connected with the development of ovarian cancer (OC), whereas the accurate regulatory mechanism of hypoxic macrophages regulating tumor advancement remains unclear. Herein, we examined whether the lysine demethylase 3 A (KDM3A) in hypoxic macrophages expedited the development of OC cells. MethodsThe contents of hypoxia inducible factor-1α (HIF-1α), CD163, CD80, KDM3A, and p-Akt/Akt were detected by western blot. Genomic Spatial Event 4630, Molecular Signatures Database, and Comparative Toxicogenomics Database were utilized for correlated gene prediction. The OC cells viability was scrutinized by cell counting kit-8 assay. The cell proliferation was inspected by 5-Ethynyl-2′-deoxyuridine assay. The vascular endothelial growth factor A (VEGF) level was detected by Enzyme-linked immunosorbent assay. ResultsM2 polarization of TAMs was associated with poor prognosis in sufferers with OC. The OC sufferers with high level of CD163 or low level of CD80 were linked with poor overall survival and disease specific survival. Hypoxia induced THP-1-derived macrophages M2 polarization. KDM3A was high-expressed in hypoxia induced macrophages. Upregulated KDM3A in hypoxic macrophages facilitated OC cell proliferation. KDM3A upregulation in hypoxic macrophages stimulated Akt signaling activation in OC cells. KDM3A in hypoxic macrophages promoted VEGF secretion to activate Akt signaling in OC cells. VEGF inhibition or Akt signaling inactivation reversed the effects of KDM3A in hypoxic macrophages on OC cells viability and proliferation. ConclusionThe KDM3A content and M2 polarization were enhanced in hypoxic macrophages, and KDM3A in hypoxic macrophages promoted OC development through regulation of the VEGF/Akt signaling pathway.

ROR1-STAT3 signaling contributes to ovarian cancer intra-tumor heterogeneity

Wnt pathway dysregulation through genetic and non-genetic alterations occurs in multiple cancers, including ovarian cancer (OC). The aberrant expression of the non-canonical Wnt signaling receptor ROR1 is thought to contribute to OC progression and drug resistance. However, the key molecular events mediated by ROR1 that are involved in OC tumorigenesis are not fully understood. Here, we show that ROR1 expression is enhanced by neoadjuvant chemotherapy, and Wnt5a binding to ROR1 can induce oncogenic signaling via AKT/ERK/STAT3 activation in OC cells. Proteomics analysis of isogenic ROR1-knockdown OC cells identified STAT3 as a downstream effector of ROR1 signaling. Transcriptomics analysis of clinical samples (n = 125) revealed that ROR1 and STAT3 are expressed at higher levels in stromal cells than in epithelial cancer cells of OC tumors, and these findings were corroborated by multiplex immunohistochemistry (mIHC) analysis of an independent OC cohort (n = 11). Our results show that ROR1 and its downstream STAT3 are co-expressed in epithelial as well as stromal cells of OC tumors, including cancer-associated fibroblasts or CAFs. Our data provides the framework to expand the clinical utility of ROR1 as a therapeutic target to overcome OC progression.

Regulations of Exosomal-Transmitted AFAP1-AS1 LncRNA on Ovarian Cancer Cell Migration and Invasion.

Adolescent ovarian cancer (OC) has high malignancy. Long non-coding RNAs (lncRNAs) have been implicated in the pathogenesis of various malignancies, but their role in adolescent OC remains poorly understood. This study aims to assess the modulatory role of Exosome-transmitted lncRNA Actin filament-associated protein 1 Antisense RNA 1 (AFAP1-AS1) on the activity of OC cells. We recruited a cohort of 40 adolescent patients diagnosed with OC and a control group of 40 healthy individuals. Serum samples were collected from both groups prior surgical intervention. Exosomes from peripheral blood and ascites were collected via differential centrifugation. The expression levels of AFAP1-AS1 in OC tissues and cell lines (IOSE-80, CAOV3, and SKOV3) were quantified using quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The exosomal particle size and surface markers were characterized through nanoparticle tracking analysis and transmission electron microscopy. Furthermore, siRNA-mediated knockdown of AFAP1-AS1 was performed in IOSE-80, CAOV3, and SKOV3 cell lines. Functional assays, including wound-healing experiments and Transwell migration assays, were conducted to evaluate cellular migration and metastasis. Our findings demonstrate that the expression of AFAP1-AS1 is significantly upregulated in OC patients' serum exosomes and ascitic fluid, correlating with unfavorable pathological features such as advanced federation international of gynecology and obstetrics (FIGO) stage and larger tumor diameter. In-vitro experiments revealed that OC cell lines and primary human OC cells showed enhanced proliferation and metastasis when exposed to ascites-derived exosomes enriched in AFAP1-AS1. Importantly, we observed that AFAP1-AS1 can be transmitted to neighboring cells via exosomal pathways. Additionally, exosomes isolated from ascites treated with siRNA targeting AFAP1-AS1 can inhibit cellular migration and invasion. Our data provide evidence for the oncogenic role of AFAP1-AS1, which is transmitted via exosomes. This finding has significant implications for understanding the molecular mechanisms of AFAP1-AS1 in the pathogenesis of adolescent ovarian cancer.

On a possible mechanism of platinum resistance development in patients with advanced ovarian cancer.

e17549 Background: The question of the mechanisms of platinum resistance development in advanced ovarian cancer (OC) remains open. The aim of the study was to reveal the relationship between the proliferative activity of OC cells, the disruption of apoptosis processes and the changes in the activity of transporter proteins that provide the efflux of chemotherapy drugs. Methods: Patients with advanced OC (T3-4N0-3M0-1) of postmenopausal age, sensitive (SPtPs, n = 23) and resistant to platinum drugs (RPtPs, n = 17), operated on after 3-6 cycles of neoadjuvant chemotherapy, were retrospectively studied. The parameters of proliferative activity (ki67), apoptosis disturbances (p53), as well as the expression of BCRP and Pgp transporter proteins were evaluated in OC tissue using immunohistochemistry methods. Statistical analysis was performed using the Mann-Whitney and Pearson tests (χ2), as well as the Spearman's rank correlation coefficient (SC). Results: In total, the dominance of the RPtPs over the SPtPs was noted in terms of intensity of the studied indicators (p < 0.05-0.003), the most significant for Pgp expression. At the same time, moderate and high values of these indicators were observed in SPtPs in 42-61% of cases, which reduced the predictive value of the revealed differences. It was of interest that statistically significant correlations between the indicators in SPtPs differed from those in RPtPs. Thus, the following values of the SC were observed in SPtPs: +0.848 (ki67-p53), -0.675 (ki67-BCRP), -0.575 (p53-BCR). In RPtPs, another intensity and/or direction of these relations were noted: +0.521 (ki 67-p53), +0.500 (ki 67-BCRP), +0.705 (p53-BCR). There were no statistically significant relationships between ki67-Pgp expression in SPtPs and RPtPs. The direction and intensity of the studied relationships could indicate changes in cell regulation in primary OC in SPtPs compared to RPtPs. Thus, in SPtPs, they reflected a significant contribution of apoptotic disturbances to the enhancement of OC cell proliferation, which was limited by the negative feedback mechanism via BCRP activity suppression indicated by the presence of an inverse correlation ki67-BCRP. In RPtPs, this mechanism was apparently already lost, which resulted in a change in the direction of the statistical relationship ki67-BCRP from reverse to direct one. Under these conditions, the positive contribution of apoptosis disruption to the proliferative activity of OC cells could obviously be supplemented by a synergistic increase in the activity of the BCRP transporter protein, which removes platinum drugs from OC cells. Conclusions: Patients with advanced OC may develop platinum resistance due to discoordination of proliferation, apoptosis, and regulation of the activity of the BCRP transporter protein.

Pardaxin Activates Excessive Mitophagy and Mitochondria-Mediated Apoptosis in Human Ovarian Cancer by Inducing Reactive Oxygen Species.

Most ovarian cancer (OC) patients are diagnosed with stage III or higher disease, resulting in a poor prognosis. Currently, paclitaxel combined with carboplatin shows the best treatment outcome for OC. However, no effective drug is available for patients that do not respond to treatment; thus, new drugs for OC are needed. We evaluated the antimicrobial peptide, pardaxin, in PA-1 and SKOV3 cells. Pardaxin induced apoptosis as determined by MTT and TUNEL assays, as well as activation of caspases-9/3, Bid, t-Bid, and Bax, whereas Bcl-2 was downregulated. The IC50 values for pardaxin were 4.6–3.0 μM at 24 and 48 h. Mitochondrial and intracellular reactive oxygen species (ROS) were overproduced and associated with disrupted mitochondrial membrane potential and respiratory capacity. Additionally, the mitochondrial network was fragmented with downregulated fusogenic proteins, MFN1/2 and L-/S-OPA1, and upregulated fission-related proteins, DRP1 and FIS1. Autophagy was also activated as evidenced by increased expression of autophagosome formation-related proteins, Beclin, p62, and LC3. Enhanced mitochondrial fragmentation and autophagy indicate that mitophagy was activated. ROS-induced cytotoxicity was reversed by the addition of N-acetylcysteine, confirming ROS overproduction as a contributor. Taken together, pardaxin demonstrated promising anticancer activity in OC cells, which warrants further preclinical development of this compound.

NF-κB Signaling in Ovarian Cancer

The NF-κB signaling pathway is a master and commander in ovarian cancer (OC) that promotes chemoresistance, cancer stem cell maintenance, metastasis and immune evasion. Many signaling pathways are dysregulated in OC and can activate NF-κB signaling through canonical or non-canonical pathways which have both overlapping and distinct roles in tumor progression. The activation of canonical NF-κB signaling has been well established for anti-apoptotic and immunomodulatory functions in response to the tumor microenvironment and the non-canonical pathway in cancer stem cell maintenance and tumor re-initiation. NF-κB activity in OC cells helps to create an immune-evasive environment and to attract infiltrating immune cells with tumor-promoting phenotypes, which in turn, drive constitutive NF-κB activation in OC cells to promote cell survival and metastasis. For these reasons, NF-κB is an attractive target in OC, but current strategies are limited and broad inhibition of this major signaling pathway in normal physiological and immunological functions may produce unwanted side effects. There are some promising pre-clinical outcomes from developing research to target and inhibit NF-κB only in the tumor-reinitiating cancer cell population of OC and concurrently activate canonical NF-κB signaling in immune cells to promote anti-tumor immunity.

Resveratrol and STAT inhibitor enhance autophagy in ovarian cancer cells.

Autophagic activity reflects cellular response to drug treatment and can be regulated by STAT3 signaling. Resveratrol inhibits STAT3 activation and causes remarkable growth arrest and cell death of ovarian cancer (OC) cells. However, the autophagic status and its relevance with resveratrol’s anti-OC effects remain unclear. We analyzed the states of autophagic activities, the nature of autophagosomes and the levels of autophagy-related proteins (LC-3, Beclin 1 and STAT3) in resveratrol-treated CAOV-3 and OVCAR-3 OC cells using multiple approaches. We elucidated the correlation of STAT3 inhibition with autophagic activity by treating OC cells with an upstream inhibitor of STAT proteins, AG490. Resveratrol efficiently suppressed growth, induced apoptosis and inactivated STAT3 signaling of the two OC cell lines. We found enhanced autophagic activity accompanied with Beclin-1 upregulation and LC3 enzymatic cleavage in resveratrol-treated OC cells. Immunofluorescent (IF) microscopic and IF-based confocal examinations demonstrated the accumulation of cytoplasmic granules co-labeled with LC3 and cytochrome C in resveratrol- or AG490-treated OC cells. Using electron microscopy, we confirmed an increase in autophagosomes and mitochondrial spheroids in either resveratrol- or AG490-treated OC cells. This study demonstrates the abilities of resveratrol to enhance apoptotic and autophagic activities in OC cells, presumably via inactivating STAT3 signaling. Resveratrol or the selective JAK2 inhibitor also leads to mitochondrial turnover, which would be unfavorable for OC cell survival and sensitize OC cells to resveratrol.