Pinin interacts with C-terminal binding proteins for RNA alternative splicing and epithelial cell identity of human ovarian cancer cells.

Unlike many other human solid tumors, ovarian tumors express many epithelial markers at a high level for cell growth and local invasion. The phosphoprotein Pinin plays a key role in epithelial cell identity. We showed that clinical ovarian tumors and ovarian cancer cell lines express a high level of Pinin when compared with normal ovarian tissues and immortalized normal ovarian surface epithelial cell lines. Pinin co-localized and physically interacted with transcriptional corepressor C-terminal binding proteins, CtBP1 and CtBP2, in the nuclei of cancer cells. Knockdown of Pinin in ovarian cancer cells resulted in specific reduction of CtBP1 protein expression, cell adhesion, anchorage-independent growth, and increased drug sensitivity. Whole transcriptomic comparison of next-generation RNA sequencing data between control ovarian cancer cell lines and cancer cell lines with respective knockdown of Pinin, CtBP1, and CtBP2 expression also showed reduced expression of CtBP1 mRNA in the Pinin knockdown cell lines. The Pinin knockdown cell lines shared significant overlap of differentially expressed genes and RNA splicing aberrations with CtBP1 knockdown and in a lesser degree with CtBP2 knockdown cancer cells. Hence, Pinin and CtBP are oncotargets that closely interact with each other to regulate transcription and pre-mRNA alternative splicing and promote cell adhesion and other epithelial characteristics of ovarian cancer cells.

Characterization of aldehyde dehydrogenase isozymes in ovarian cancer tissues and sphere cultures.

BACKGROUND: Aldehyde dehydrogenases belong to a superfamily of detoxifying enzymes that protect cells from carcinogenic aldehydes. Of the superfamily, ALDH1A1 has gained most attention because current studies have shown that its expression is associated with human cancer stem cells. However, ALDH1A1 is only one of the 19 human ALDH subfamilies currently known. The purpose of the present study was to determine if the expression and activities of other major ALDH isozymes are associated with human ovarian cancer and ovarian cancer sphere cultures. METHODS: Immunohistochemistry was used to delineate ALDH isozyme localization in clinical ovarian tissues. Western Blot analyses were performed on lysates prepared from cancer cell lines and ovarian cancer spheres to confirm the immunohistochemistry findings. Quantitative reverse transcription-polymerase chain reactions were used to measure the mRNA expression levels. The Aldefluor® assay was used to measure ALDH activity in cancer cells from the four tumor subtypes. RESULTS: Immunohistochemical staining showed significant overexpression of ALDH1A3, ALDH3A2, and ALDH7A1 isozymes in ovarian tumors relative to normal ovarian tissues. The expression and activity of ALDH1A1 is tumor type-dependent, as seen from immunohistochemisty, Western blot analysis, and the Aldefluor® assay. The expression was elevated in the mucinous and endometrioid ovarian epithelial tumors than in serous and clear cell tumors. In some serous and most clear cell tumors, ALDH1A1 expression was found in the stromal fibroblasts. RNA expression of all studied ALDH isozymes also showed higher expression in endometrioid and mucinous tumors than in the serous and clear cell subtypes. The expression of ALDH enzymes showed tumor type-dependent induction in ovarian cancer cells growing as sphere suspensions in serum-free medium. CONCLUSIONS: The results of our study indicate that ALDH enzyme expression and activity may be associated with specific cell types in ovarian tumor tissues and vary according to cell states. Elucidating the function of the ALDH isozymes in lineage differentiation and pathogenesis may have significant implications for ovarian cancer pathophysiology.

Clinical epidemiology and management of gestational trophoblastic neoplasia in Hungary in the past 34 years.

OBJECTIVE: To review our clinical experience in the treatment of patients with gestational trophoblastic neoplasia (GTN) over the past 34 years in our national trophoblastic disease center. STUDY DESIGN: Between January 1, 1977, and December 31, 2010, 331 patients with low-risk GTN and 174 patients with high-risk GTN (altogether 505) were treated. The patients were directed to the national trophoblastic disease center from all parts of Hungary. The patients were between 14 and 54 years of age, with an average age of 28.7 years. Primary chemotherapy was selected based upon the patient's stage and prognostic score of GTN. RESULTS: Among 237 low-risk patients, 228 (96.2%) achieved remission as a result of primary methotrexate (MTX) therapy. Out of 94 low-risk patients 90 (95.7%) achieved remission as a result of primary actinomycin-D (Act-D) therapy. MTX, Act-D and cyclophosphamide (MAC) as a primary therapy was used in 118 high-risk cases, and 110 (93.2%) patients achieved complete remission. A total of 32 high-risk patients were treated with the etoposide, high-dose MTX/folinic acid, Act-D, cyclophosphamide and vincristine (EMA-CO) regimen, and of 26 primary therapies complete remission was achieved in 21 (80.8%) cases. Primary cisplatin, etoposide and bleomycin (CEB) therapy was successful in 16 of 17 high-risk cases (94.1%). Metastases were found in 47.3% (239/505) of the patients. Hysterectomy was performed in 68 of 505 (13.5%) cases. Chemotherapy, surgical intervention or other supplementary treatments resulted in 100% remission in cases of nonmetastatic and metastatic low-risk disease. Comparison of mean prognostic scores resulted in significant differences between CEB and MAC, CEB and EMA-CO, and MAC and EMA-CO. CONCLUSION: Our data indicate that MTX/folinic acid or Act-D should be the primary treatment in patients with nonmetastatic or metastatic low-risk GTN. Patients with high-risk metastatic GTN should be treated primarily with combination chemotherapy. Our data support the effectiveness of MAC, EMA-CO and CEB regimens. Results also show that patient care under the direction of experienced clinicians serves to optimize the opportunity for cure and minimize morbidity.

Vascular endothelial growth factors and their receptors and regulators in gestational trophoblastic diseases and normal placenta.

OBJECTIVE: To study the expression of vascular endothelial growth factors (VEGFs), placental growth factor (PLGF) and their receptors (VEGFR-1, -2, -3) and their regulators (IL-6, CD147) in normal placenta and gestational trophoblastic disease (GTD) in order to evaluate their potential role in the biology of GTD. STUDY DESIGN: Paraffin sections of 10 normal, first-trimester placentas, 10 partial moles, 10 complete moles, 5 choriocarcinomas and 5 placental site trophoblastic tumors (PSTTs) were studied immunohistochemically for expression of VEGFR-1, VEGFR-2, VEGFR-3, IL-6, PLGF and CD147. Immunolocalization of VEGF, Angiopoietin-1 and Angiopoietin-2 was performed on 5 choriocarcinomas and 5 PSTTs. The levels of VEGF and VEGFR-2 were determined in supernatants and lysates of normal trophoblast, JEG-3 and JAR choriocarcinoma cells with electrochemiluminescence assays. RESULTS: The normal placenta had significantly stronger expression of VEGFR-2 than did those of partial and complete mole (p = 0.001, p = 0.003). VEGF, Angiopoietin-1 and Angiopoietin-2 expression in PSTT were significantly higher than those in choriocarcinoma (p = 0.002, p= 0.01, p = 0.038). Choriocarcinoma showed stronger intensity of staining for VEGFR-3 than did normal placenta, partial and complete mole (p = 0.036, p = 0.038, p = 0.05). Choriocarcinoma had significantly stronger staining of CD147 than did partial and complete mole (p<0.01, p<0.01). PSTT exhibited significantly stronger staining for IL-6 than did choriocarcinoma (p = 0.03). CONCLUSION: PSTTs exhibited strong staining for VEGF, and choriocarcinoma showed strong staining for VEGFR-3. Agents that inhibit the activity of VEGF and VEGF receptors may prove to be useful in the therapy of gestational trophoblastic neoplasia.

Matrix metalloproteinases and their inhibitors and inducer in gestational trophoblastic diseases and normal placenta.

OBJECTIVES: This study aimed to investigate the expression of recently identified matrix metalloproteinases (MMPs), their inhibitors (TIMPs), and inducer (CD147) in a wide range of gestational trophoblastic diseases (GTD) thereby expanding our understanding of the potential role of MMPs in GTD. METHODS: Paraffin sections of 10 normal first-trimester placentas (NP), 10 partial moles (PM), 10 complete moles (CM), 5 choriocarcinomas (CCA) and 5 placental site trophoblastic tumors (PSTT) were studied immunohistochemically for expression of MMP-7, MMP-14, MMP-21, MMP-28, TIMP-3, TIMP-4 and CD147. Immunolocalization of MMP-1, MMP-2, MMP-3, MMP-9, MMP-13 and TIMP-1 was performed on 5 CCA and 5 PSTTs. RESULTS: CCA showed stronger intensity for MMP-14 and MMP-28 than PSTT (p<0.05, p<0.05). CCA and PSTT had stronger expression of MMP-21 than NP, PM and CM (p<0.05, p<0.05, p<0.01). PSTT (p<0.05, p<0.05), NP (p<0.01, p<0.01) and CM (p<0.01, p<0.05) showed stronger staining for TIMP-3 and TIMP-4 than CCA. CONCLUSION: Choriocarcinoma's high expression of MMPs and low expression of MMP inhibitors may contribute to its invasiveness and metastatic potential. Similarly, PSTT's lower expression of MMPs and high expression of MMP inhibitors may partly explain its lower invasiveness. Agents that inhibit MMP may prove useful in treating GTD.