Human Ovarian Carcinoma Tissues Research Articles

Knockdown of LIMD2 inhibits the progression of ovarian carcinoma through ERK1/2 pathway.

The incidence rate of ovarian carcinoma (OC) is the third of the female reproductive system malignant tumors, while its mortality rate ranks first among causes of female reproductive system tumor related death in the world. In the present research, we investigated the specific role of LIMD2 through LIMD2 knockdown in OC cells. The results of online analysis and expression detection proved that LIMD2 was up-regulated in human OC tissues and cells. Knockdown of LIMD2 inhibited the proliferation, migration and invasion in OC cells. LIMD2 knockdown promoted the apoptosis, as well as the expression of Cleaved-Caspase3 and Bax. Importantly, knockdown of LIMD2 promotes cell autophagy. LC3-II/I ratio and Beclin1 expression increased in LIMD2 knockdown cells, while P62 expression declined in LIMD2 knockdown cells. Additionally, the phosphorylation of ERK1/2 was inhibited by the knockdown of LIMD2 in SKOV3 and OVCAR3 cells. Knockdown of LIMD2 inhibits cell proliferation, migration, invasion and autophagy, and promotes the apoptosis through the ERK1/2 signaling pathway, suggesting that LIMD2-siRNA may be an effective molecule to prevent OC progression.

Abstract 1472: Paraoxonase 3 is a novel tumor suppressor protein in xenograft mouse model

Abstract Introduction: Dysfunction of mitochondrial respiratory chains or its associated machinery favors the aerobic glycolysis leading to upregulation of genes related to cell proliferation, metastasis, drug resistant and cancer cell stemness, i.e., the Warburg effect, which has a major role in the pathogenesis of tumor formation. Various studies have documented that perturbation of mitochondria leads to apoptosis suggesting that the precise spatiotemporal regulation of mitochondrial function is a critical regulator of both cell survival and death, whcih determine tumorigenesis. Paraoxonase 3 (PON3) is an intracellular protein localized to the mitochondrial associated membrane. PON3 binds coenzymes Q10 and regulates the respiratory complex activity and prevents the ubisemiquinone-mediated mitochondrial superoxide levels in response to stress conditions. PON3 deficiency leads to dysfunction of mitochondria, which along with an increase in mitochondrial oxidative stress causes systemic inflammation, atherosclerosis, obesity and gall stone formation. PON3 is upregulated in ovarian cancer tissues. However, it's expression in various stages of ovarian cancer and its role on cancer development have not been studied. Hypothesis: PON3 expression may regulate the ovarian cancer development by enhancing the mitochondrial function. Methods and Results: Using human ovarian carcinoma tissue array, we identified that PON3 expression was higher in both early and late stages of ovarian cancer when compared to normal tissue. Interestingly, we demonstrated that overexpression of PON3 prevented tumor formation in a mouse ovarian cancer xenograft model. Overexpression of PON3, (i) reduced the tumor angiogenesis marker, CD31 levels in the tumor microenvironment and (ii) inhibited ovarian cancer cell proliferation in both normoxic and hypoxic condition in vitro. Moreover, PON3 reduced VEGF levels (but not IGF-1 levels) under hypoxic conditions. Furthermore, mechanistically, overexpression of PON3 decreased the VEGF level by accelerating the proteasome-dependent protein degradation of hypoxia inducible factor-1 α (HIF-1α) under hypoxic conditions. Finally, we demonstrate that the inhibitory effect of PON3 on HIF-1α levels is, in part, mediated by mitochondrial function. Conclusion: We report for the first time that PON3 functions as a tumor suppressor in ovarian cancer possibly by suppressing VEGF signaling via HIF-1α by enhancing the mitochondrial function suggesting that PON3 might be a successful strategy to inhibit the ovarian cancer development. Citation Format: Asokan Devarajan, Feng Su, Dawoud Sulaiman, Dorothy Nguyen, Robin Farias-Eisner, Srinivasa T. Reddy. Paraoxonase 3 is a novel tumor suppressor protein in xenograft mouse model [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1472.

PML silencing inhibits cell proliferation and induces DNA damage in cultured ovarian cancer cells.

The promyelocytic leukemia (PML) gene is a tumor suppressor gene. It was first identified in acute promyelocytic leukemia, in which it is fused to retinoic acid receptor α by the (15;17) chromosomal translocation. The function of the PML protein is frequently lost or aberrant in human solid tumors. In human ovarian carcinoma tissue, PML detected by immunohistochemistry was highly expressed. A PML-silencing vector, pSRG-shPml, was constructed and used to transfect human ovarian cancer cells. Cells were cultured and selected with puromycin for 10–15 days, and then the PML mRNA expression levels were detected by RT-qPCR and immunofluorescence. Proliferation and clone number of PML-depleted cells were detected using MTT assay and colony-forming assay. The protein expression associated with DNA damage and apoptosis was assessed in PML-depleted cells using western blot analysis and immunofluorescence. The results showed that PML was highly expressed in human ovarian tissue. The proliferation and colony formation of ovarian cancer cells were significantly inhibited after PML was depleted. Western blot analysis and immunofluorescence revealed that p-H2AX and cleaved caspase-3 expression significantly increased after PML silencing. PML was located in the nucleus, and it formed foci after X-ray irradiation. PML foci increased significantly with increasing irradiation doses.

Clinical Impact of microRNAs Associated With Cancer Stem Cells as a Prognostic Factor in Ovarian Carcinoma.

Background: Ovarian carcinoma is a highly lethal gynecological malignancy due to its frequent relapses and adoption of chemoresistance. To develop new biomarkers for disease progression in ovarian carcinoma, CSCs, which are considered to contribute to disease relapse and metastasis, were isolated from human ovarian carcinoma tissues, and differentially expressed microRNAs (miRNAs) in CSCs were identified and assessed the clinical implication of expression of these miRNAs.Methods: Primary cancer cells derived from human ovarian carcinomas were cultured and spheroid-forming cells (SFCs) were isolated. Profiles of miRNA expression in CSC-like SFCs were identified by miRNA microarray and the results were validated by quantitative real-time RT-PCR (qRT-PCR). We also assessed the correlations between miRNA expression levels and clinicopathological parameters in ovarian carcinomas.Results: Five miRNAs (miR-5703, miR-630, miR-1246, miR-424-5p, and miR-320b) were significantly dysregulated in CSC-like SFCs compared with primary cancer cells. The qRT-PCR showed that miR-5703 and miR-1246 expression was significantly higher in ovarian cancer cells than in normal control cells, whereas the miR-424-5p level was significantly lower. Decreased expression of miR-424-5p was significantly associated with distant metastasis in high stage (stage IIII & IV) carcinomas (35.5% vs. 72.2%, respectively, p=0.013)Conclusion: Taken together, miR-5703, miR-630, miR-1246, miR-424-5p, and miR-320b are useful markers for enriching ovarian CSCs. Decreased expression of miR-424-5p in ovarian carcinoma might be a putative biomarker for distant metastasis in ovarian carcinoma.

Folic acid-targeted iron oxide nanoparticles as contrast agents for magnetic resonance imaging of human ovarian cancer.

BackgroundImproved methods for the early and specific detection of ovarian cancer are needed.MethodsIn this experimental study, we used folic acid (FA)-targeted iron oxide (Fe3O4) nanoparticles (NPs) as a T2-negative contrast agent for magnetic resonance (MR) imaging to accurately detect ovarian cancer tissues in an intraperitoneal xenograft tumor model. Human serous ovarian cell line (Skov-3), with overexpressed FA receptors, was chosen as the targeted tumor cell mode. For in vivo experiments, the cells were injected intraperitoneally into nude mice to produce intraabdominal ovarian cancers. FA-targeted and non-targeted Fe3O4 NPs were prepared.ResultsFA-targeted Fe3O4 NPs with a mean size of 9.2 ± 1.7 nm have a negligible cytotoxicity to human serous ovarian cell line (Skov-3). Importantly, the results of cellular uptake suggested that FA-targeted Fe3O4 NPs have a targeting specificity to Skov-3 cells overexpressing FA receptors. FA-targeted Fe3O4 NPs could be specifically localized by magnetic resonance (MR) imaging to the intraperitoneal human ovarian carcinoma tissues, as documented by a statistically significant difference (p = 0.002, n = 3) in T2 signal intensities of xenograft tumor tissues when injected with FA-targeted and non-targeted Fe3O4 NPs at 4 h post-injection.ConclusionFA-targeted Fe3O4 NPs appear to be promising agents for the detection of human ovarian carcinoma by MR imaging, and possibly also for the hyperthermal treatment of the tumors.

Downregulation of SASH1 correlates with tumor progression and poor prognosis in ovarian carcinoma.

SAM- and SH3-domain containing 1 (SASH1) is a recently identified tumor suppressor gene that is required in the tumorigenesis of breast and other solid carcinomas. The SASH1 protein contains SH3 and SAM domains, indicating that it may serve an important role in intracellular signal transduction. The purpose of the present study was to investigate the expression of SASH1 in ovarian carcinoma and the correlation between its expression with clinical pathological features and clinical significance, and the effect of SASH1 on cell proliferation, apoptosis and migration of ovarian SKOV3 cells. The human ovarian carcinoma tissues and adjacent normal tissues were collected following surgery. Reverse transcription-quantitative polymerase chain reaction and western blot analysis were used to detect the expression levels of SASH1 mRNA and protein, respectively. The expression levels of SASH1 mRNA and protein in ovarian carcinoma tissues were significantly lower than that observed in adjacent normal tissues (P<0.05). The expression levels of SASH1 in samples from patients without lymph nodes metastasis and patients with early FIGO stage was lower than those with lymph nodes metastasis and patients with advanced FIGO stage (P<0.05). Flow cytometry analysis and Transwell invasion chamber experiments were used to investigate the effect of SASH1 on the cell proliferation, apoptosis and migration of SKOV3 cells. The recombinant plasmid pcDNA3.1-SASH1 was constructed and transfected into SKOV3 cells. In addition, the SKOV3 cells in the pcDNA3.1-SASH1 group exhibited significantly reduced cell growth, proliferation, and migration ability compared to the empty vector group and normal group (P<0.01). There were a greater number of apoptotic cells in the pcDNA3.1-SASH1 group compared to the empty vector group and normal group (P<0.01). Taken together, these results indicated that SASH1 may be a tumor suppressor gene in ovarian carcinoma, and SASH1 expression inhibited growth, proliferation and migration, and enhanced apoptosis of SKOV3 cells.

Characteristic odour in the blood reveals ovarian carcinoma

BackgroundOvarian carcinoma represents about 4% of all cancers diagnosed in women worldwide. Mortality rate is high, over 50%, mainly due to late diagnosis. Currently there are no acceptable screening techniques available, although ovarian cancer belongs to the group of malignancies for which mortality could be dramatically reduced by early diagnosis.In a recently published study, we clearly demonstrated that human ovarian carcinoma tissues can be characterized by a specific odour, detectable by a trained dog. Another recent study confirmed these results using an electronic nose.MethodsIn the present work, we examined whether the cancer-specific odour can also be found in the blood. Two specially trained dogs were used. Both ovarian cancer tissues and blood from patients with ovarian carcinoma were tested.ResultsThe tissue tests showed sensitivity of 100% and specificity of 95%, while the blood tests showed sensitivity of 100% and specificity of 98%.ConclusionsThe present study strongly suggests that the characteristic odour emitted by ovarian cancer samples is also present in blood (plasma) taken from patients with the disease. This finding opens possibilities for future screening of healthy populations for early diagnosis of ovarian carcinoma. A future challenge is to develop a sensitive electronic nose for screening of ovarian carcinoma by testing the blood/plasma to detect the disease at a stage early enough for treatment to be effective.

Motility-related actinin alpha-4 is associated with advanced and metastatic ovarian carcinoma

Advanced and metastatic ovarian cancer is a leading cause of death from gynecologic malignancies. A more detailed understanding of the factors controlling invasion and metastasis may lead to novel anti-metastatic therapies. To model cellular interactions that occur during intraperitoneal metastasis, comparative cDNA microarray analysis and confirmatory real-time reverse transcription PCR (RT-PCR) were employed to uncover changes in gene expression that may occur in late stage ovarian cancer in response to microenvironmental cues, particularly native three-dimensional collagen I. Gene expression in human ovarian carcinoma tissues was evaluated on the RNA and protein level using real-time RT-PCR and immunohistochemistry. Cell invasion and migration were evaluated in a collagen invasion assay and a scratch wound assay. Three-dimensional collagen I culture led to differential expression of several genes. The role of actinin alpha-4 (ACTN4), a cytoskeleton-associated protein implicated in the regulation of cell motility, was examined in detail. ACTN4 RNA and protein expression were associated with advanced and metastatic human ovarian carcinoma. This report demonstrates that a cytoskeletal-associated protein ACTN4 is upregulated by three-dimensional collagen culture conditions, leading to increased invasion and motility of ovarian cancer cells. Expression of ACTN4 in human ovarian tumors was found to be associated with advanced-stage disease and peritoneal metastases.

WWOX protein expression varies among ovarian carcinoma histotypes and correlates with less favorable outcome

BackgroundThe putative tumor suppressor WWOX gene spans the common chromosomal fragile site 16D (FRA16D) at chromosome area 16q23.3-24.1. This region is a frequent target for loss of heterozygosity and chromosomal rearrangement in ovarian, breast, hepatocellular, prostate carcinomas and other neoplasias. The goal of these studies was to evaluate WWOX protein expression levels in ovarian carcinomas to determine if they correlated with clinico-pathological parameters, thus providing additional support for WWOX functioning as a tumor suppressor.MethodsWe performed WWOX protein expression analyses by means of immunobloting and immunohistochemistry on normal ovaries and specific human ovarian carcinoma Tissue Microarrays (n = 444). Univariate analysis of clinical-pathological parameters based on WWOX staining was determined by χ2 test with Yates' correction. The basic significance level was fixed at p < 0.05.ResultsImmunoblotting analysis from normal ovarian samples demonstrated consistently strong WWOX expression while 37% ovarian carcinomas showed reduced or undetectable WWOX protein expression levels. The immunohistochemistry of normal human ovarian tissue sections confirmed strong WWOX expression in ovarian surface epithelial cells and in epithelial inclusion cysts within the cortex. Out of 444 ovarian carcinoma samples analyzed 30% of tumors showed lack of or barely detectable WWOX expression. The remaining ovarian carcinomas (70%) stained moderately to strongly positive for this protein. The two histotypes showing significant loss of WWOX expression were of the Mucinous (70%) and Clear Cell (42%) types. Reduced WWOX expression demonstrated a significant association with clinical Stage IV (FIGO) (p = 0.007), negative Progesterone Receptor (PR) status (p = 0.008) and shorter overall survival (p = 0.03).ConclusionThese data indicate that WWOX protein expression is highly variable among ovarian carcinoma histotypes. It was also observed that subsets of ovarian tumors demonstrated loss of WWOX expression and is potentially associated with patient outcome.

Suppression of the TIG3 tumor suppressor gene in human ovarian carcinomas is mediated via mitogen‐activated kinase‐dependent and ‐independent mechanisms

The TIG3 gene is a retinoic acid inducible class II tumor suppressor gene downregulated in several human tumors and malignant cell lines. Diminished TIG3 expression correlates with decreased differentiation whereas forced expression of TIG3 suppresses oncogenic signaling pathways and subsequently induces differentiation or apoptosis in tumor cells. Analysis of TIG3 mRNA expression in a large set of cDNA pools derived from matched tumor and normal human tissues showed a significant downregulation of TIG3 in 29% of the cDNA samples obtained from ovarian carcinomas. Using in situ hybridization, we demonstrated expression of TIG3 in the epithelial lining of 7 normal ovaries but loss of TIG3 expression in 15/19 of human ovarian carcinoma tissues. In SKOV-3, CAOV-3 and ES-2 ovarian carcinoma cell lines, downregulation of TIG3 mRNA was reversible and dependent on an activated MEK-ERK signaling pathway. Re-expression of TIG3 mRNA in these cells upon specific interference with the MEK-pathway was correlated with growth inhibition of the cells. In OVCAR-3 and A27/80 ovarian carcinoma cells, TIG3 suppression is MEK-ERK independent, but expression could be reconstituted upon interferon gamma (IFNgamma) induction. Overexpression of TIG3 in A27/80 ovarian carcinoma cells significantly impaired cell growth and despite increased mRNA levels, TIG3 protein was hardly detectable. These results suggest that TIG3 is negatively regulated by an activated MEK-ERK signaling pathway. Further mechanisms must interfere with TIG3 expression that are independent of MEK and partially include interferon-responsive components.

Cross-linked telopeptides of type I and III collagens in malignant ovarian tumours in vivo.

Malignant tumours often induce a fibroproliferative response in the adjacent stroma, characterized by increased expression of type I and type III procollagens. In normal tissues, fibrillar collagens normally undergo extensive intermolecular cross-linking that provides tensile strength to the tissue. Here we set out to characterize collagen cross-linking in human ovarian carcinoma tissue in vivo. Biochemical and immunochemical methods were used for cross-linked telopeptides of type I and III collagens in samples of benign and malignant serous tumours. The locations and staining patterns of these proteins were visualized immunohistochemically. The contents of both total collagen and the cross-linked type I and type III collagens in the malignant samples were only about 20% of those in the benign tumours. The cross-linked telopeptide antigens derived from the collagens were smaller and more heterogeneous in size in the malignant than in the benign tumours, indicating a defective cross-linking process scarcely leading to the formation of mature cross-links in the collagen fibres in malignancy. Immunostaining revealed disorganized type I and type III collagen bundles in carcinomas. These findings suggest that the collagen cross-linking process is aberrant in malignant tumours, possibly resulting in increased susceptibility of tumour collagens for the proteolysis often associated with tumour invasion. © 1999 Cancer Research Campaign

Trypsinogen expression in human ovarian carcinomas.

Increased secretion of matrix metalloproteinases and serine proteinases is well known to be associated with cancer invasion and metastasis. We aimed to elucidate the implication of trypsin, a serine proteinase and a representative digestive enzyme in invasion and metastasis of human carcinomas. Northern blot, RT-PCR and Western blot analyses and immunohistochemical studies were performed to detect and analyze trypsinogen expression in 5 ovarian carcinoma cell lines and 10 human ovarian carcinoma tissues using a DNA probe for trypsinogen I, and monoclonal and polyclonal antibodies to human trypsin I. Among the 5 ovarian carcinoma cell lines, only the MCAS (mucinous cystadenocarcinoma) cell line showed a high level of trypsinogen production and mRNA expression by Western and Northern blot analyses, respectively. However, Southern blot analysis of RT-PCR products could detect considerable levels of trypsinogen mRNA in all ovarian cancer cell lines. In Northern analysis of ovarian cancer tissues, all advanced cancer samples showed trypsinogen gene expression. Serous cystadenocarcinomas exhibited particularly high levels of gene expression. Immunohistochemical staining also detected trypsin in ovarian carcinoma tissues. In contrast, normal ovaries and tumors with low malignant potential did not show trypsinogen expression. Our results demonstrate the extra-pancreatic production and distribution of trypsinogen in human ovarian carcinomas.

Monoclonal Antibody Against Human Ovarian Tumor-Associated Antigens

Mouse monoclonal antibodies (OV-TL 3) were raised against human ovarian tumor-associated antigens for diagnostic purposes. A cloned hybridoma cell line was obtained by fusion of murine myeloma cells with spleen lymphocytes from BALB/c mice immunized with a tumor cell suspension prepared from an ovarian endometrioid carcinoma. The antibodies were initially screened for their ability to bind on frozen sections of human ovarian carcinoma tissue and a negative reaction on gastric carcinoma tissue by indirect immunofluorescence. The reactivity of the selected OV-TL 3 clone (IgG1 subclass) was studied on normal and neoplastic tissues as well as on a cell line derived from the original tumor cell suspension used for immunization. OV-TL 3 antibodies stained frozen sections of human ovarian carcinomas of the following histological types: serous, mucinous, endometrioid, and clear cell. No reaction was found with breast cancers or other nongynecological tumors. No differences in staining pattern were observed between primary and metastatic ovarian carcinomas. OV-TL 3 antibodies brightly stained ovarian carcinoma cell clusters in ascitic fluids and left unstained mesothelial cells and peripheral blood cells. The OV-TL 3-defined antigen also remained strongly expressed on a cell line derived from the endometrioid ovarian carcinoma originally used for generation of OV-TL 3 clone. Reactivity was weak and irregular in a few ovarian cysts, while traces of fluorescence were sometimes detected in epithelial cells lining the female genital tract. In only 3 specimens of 15 endometrium carcinomas was weak focal reactivity with OV-TL 3 antibodies observed. The results of the immunofluorescence study were confirmed by the more sensitive avidin-biotin method and by 125I-labeled OV-TL 3 antibodies. Thus OV-TL 3 recognizes a common antigen for most ovarian carcinomas and may be a useful tool for rapid diagnosis of ovarian carcinomas.