Aurora-A kinase is differentially expressed in the nucleus and cytoplasm in normal Müllerian epithelium and benign, borderline and malignant serous ovarian neoplasms.

BACKGROUND: Aurora-A kinase is important for cellular proliferation and is implicated in the tumorigenesis of several malignancies, including of the ovary. Information regarding the expression patterns of Aurora-A in normal Müllerian epithelium as well as benign, borderline and malignant epithelial ovarian neoplasms is limited. METHODS: We investigated Aurora-A expression by immunohistochemistry in 15 benign, 19 borderline and 17 malignant ovarian serous tumors, and 16 benign, 8 borderline, and 2 malignant ovarian mucinous tumors. Twelve fimbriae from seven patients served as normal Müllerian epithelium controls. We also examined Aurora-A protein expression by western blot in normal fimbriae and tumor specimens. RESULTS: All normal fimbriae (n = 12) showed nuclear but not cytoplasmic Aurora-A immunoreactivity by immunohistochemistry. Benign ovarian tumors also showed strong nuclear Aurora-A immunoreactivity. Forty-eight percent (13/27) of borderline tumors demonstrated nuclear Aurora-A immunoreactivity, while the remainder (52%, 14/27) lacked Aurora-A staining. Nuclear Aurora-A immunoreactivity was absent in all malignant serous tumors, however, 47% (8/17) demonstrated perinuclear cytoplasmic staining. These results were statistically significant when tumor class (benign/borderline/malignant) was compared to immunoreactivity localization or intensity (Fisher Exact Test, p < 0.01). Western blot analysis confirmed the greater nuclear Aurora-A expression in control Müllerian epithelium compared to borderline and malignant tumors. CONCLUSION: Aurora-A kinase is differentially expressed across normal Müllerian epithelium, benign and borderline serous and mucinous ovarian epithelial neoplasms and malignant serous ovarian tumors., with nuclear expression of unphosphorylated Aurora-A being present in normal and benign neoplastic epithelium, and lost in malignant serous neoplasms. Further studies of the possible biological and clinical implications of the loss of nuclear Aurora-A expression in ovarian tumors, and its role in ovarian carcinogenesis are warranted.

Nuclear localization of phosphorylated ERK1 and ERK2 as markers for the progression of ovarian cancer.

We examined the possibility that the localization of phosphorylated ERK1 and ERK2 (pERK1/2) can serve as a marker for the development of benign and borderline tumors as well as carcinoma of the ovary by an immunohistochemical method on ovarian paraffin sections, obtained from women aged 41-83 years. In normal tissue, 28.3% of nuclei were labeled, mainly confined to the epithelial cells at the surface of the ovary. In benign serous tumors, the label rose to 55.0%, while the intensity of the staining was weak. In contrast, in borderline serous tumors and in ovarian serous carcinoma (stage II) 52.1% and 70.3% of nuclei, respectively, were labeled with a high intensity. In mucinous benign tumors, the number of labeled nuclei was as in the control, but in addition, 49.4% of the cells demonstrated high concentration of pERK1/2 in aggregated form that was evident in the cytoplasm of the cells. In the mucinous and endometrioid ovarian carcinomas (stage II) very intensive labeling was found in 60% and 77.3% of cells, respectively. It is, therefore, suggested that since nuclear pERK1/2 can be mitogenic, it can serve as a reliable marker for the progression of ovarian cancer. Interestingly, the intense labeling of pERK1/2 was mainly confined to the peripheral areas of ovarian endometrioid carcinoma (stage II). In addition, all tumor cells in this class of cancer were positively stained with mutated p53. It seems, therefore, that immunohistochemical staining of normal and ovarian tumor cells with anti-pERK1/2 is a reliable marker for early detection of the cancer, which may assist in the early diagnosis and prognosis of this lethal disease.

Expression of transmembrane carbonic anhydrases IX and XII in ovarian tumours.

AIMS: Carbonic anhydrase (CA) isozymes IX and XII have been suggested to play a role in oncogenic processes. The aim of the present study was to investigate CA IX and XII expression in patients with ovarian tumours. METHODS AND RESULTS: A series of ovarian tumours was immunostained for CA IX and XII and the results were correlated with histopathological and clinical parameters. Most cases of borderline mucinous cystadenomas, mucinous cystadenocarcinomas and serous cystadenocarcinomas were moderately or strongly positive for CA IX. In malignant tumours, the staining was most prominent in hypoxic regions. Expression of CA XII was detected in all tumour categories, although the mean staining intensity was weaker than for CA IX in all groups except for clear cell carcinomas. CONCLUSIONS: The wide expression of CA IX and XII in ovarian tumours suggests that these isozymes could represent potential targets in ovarian cancer therapy. The expression pattern of CA IX suggests that it could also serve as a useful histopathological marker protein for hypoxia in malignant ovarian tumours.

Expression of cyclooxygenase-2 and inducible nitric oxide synthase in ovarian surface epithelial carcinomas: is there any correlation with angiogenesis or clinicopathologic parameters?

Cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) products have been implicated in the regulation of immune system, tumor cell apoptosis, and angiogenesis in many human tumors. In this study, we investigated the expression of COX-2 and iNOS in ovarian carcinomas by immunohistochemistry and correlated the results with other prognostic parameters. Specimens from 100 ovarian carcinomas were studied by immunohistochemistry for COX-2 and iNOS expression, and angiogenesis microvessel density (MVD) was evaluated by CD34-stained microvessels. High COX-2 expression was observed in 85% of carcinomas. No correlation was found between COX-2 expression and clinicopathologic variables. Patients with high COX-2-expressed tumors had shorter overall survival, but it is not statistically significant. Expression of iNOS in serous and low-grade carcinomas was significantly higher than that in nonserous and high-grade carcinomas (P < 0.05). There was a positive correlation between COX-2 and iNOS expression (P= 0.009). No correlation of COX-2 and iNOS expression with MVD was found. Expression of iNOS showed no effect on survival of the patients. We found that iNOS expression might act in the first steps of carcinogenesis, whereas COX-2 expression was seen in more advanced tumors. Shorter overall survival of patients with high COX-2 expression might indicate new targets for therapy.

Increasing expression of serine protease matriptase in ovarian tumors: tissue microarray analysis of immunostaining score with clinicopathological parameters.

Matriptase is a type II transmembrane serine protease expressed by cells of surface epithelial origin, including epithelial ovarian tumor cells. Matriptase cleaves and activates proteins implicated in the progression of cancer and represents a potential prognostic and therapeutic target. The aim of this study was to examine the expression of matriptase in ovarian tumors and to assign clinicopathological correlations. Immunohistochemical analysis of matriptase was performed in tissue microarrays of 164 ovarian neoplasms including 84 serous adenocarcinomas, 23 mucinous adenocarcinomas, 10 endometrioid adenocarcinomas, six yolk sac tumors, 12 clear cell carcinomas, six dysgerminomas, eight granulosa cell tumors, four transitional cell carcinomas, five fibromas, and six Brenner tumors. All ovarian tumors except the fibromas and Brenner tumors showed significant expression of matriptase. The matriptase scores were significantly higher in the tumors than in their nontumor counterparts (304+/-26 for serous adenocarcinoma; 361+/-28 for mucinous adenocarcinoma; 254+/-17 for endometrioid adenocarcinoma; 205+/-19 for yolk sac tumor; 162+/-16 for clear cell carcinoma; 109+/-11 for dysgerminoma; 105+/-9 for granulosa cell tumor; and 226+/-18 for transitional cell carcinoma). Matriptase scores in serous adenocarcinoma were correlated with TNM stage and FIGO stage. Our findings demonstrate for the first time that matriptase is overexpressed in many malignant ovarian tumors. It may be a novel biomarker for diagnosis and treatment of malignant ovarian tumors.

Expression status and mutational analysis of the ras and B-raf genes in ovarian granulosa cell and epithelial tumors.

OBJECTIVES: The molecular pathogenesis of granulosa cell tumors of the ovary (GCT) is not understood. Activating mutations in the K-, N-, and H-ras protooncogenes have been identified in a wide range of human cancers, including ovarian epithelial tumors. Furthermore, an apparent association has recently been reported between the presence of ras and B-raf mutations in the same cancer types. Activation of the ras/raf pathway would be predicted to be tumorigenic in granulosa cells. METHODS: Gene expression patterns of the three ras and B-raf genes were determined in a panel of GCT and ovarian epithelial tumors, and in normal premenopausal ovaries. Expression was determined by RT-PCR using gene-specific primers combined with Southern blot analysis of the PCR products using gene-specific (32)P-labeled probes. Direct sequence analysis was used to screen for known activating mutations. RESULTS: Widespread expression of the four genes was observed in all tumor types examined. Compared to the normal ovaries, none of the genes was expressed at significantly higher levels in any of the tumor types examined. A heterozygous point mutation in codon 12 of the K-ras gene was found in five of the 10 mucinous tumors. No B-raf mutations were detected in the mucinous tumors. No mutations were detected in any of the genes in the cohort of GCT. CONCLUSION: These results suggest that neither overexpression nor activating mutations of the ras or B-raf genes are associated with the development of GCT.

Clinical implication of expression of cyclooxygenase-2 and peroxisome proliferator activated-receptor gamma in epithelial ovarian tumours.

Expression of cyclooxygenase (COX)-2 plays a key role in tumorigenesis and development and peroxisome proliferator-activated receptor gamma (PPARgamma) has been implicated in the control of COX-2 expression in some tissues. The aim of this study is to investigate (1) whether expression of COX-2 and PPARgamma is associated with ovarian carcinogenesis and progression of ovarian tumours and (2) whether COX-2 expression is controlled through ligand-mediated activation of PPARgamma in ovarian carcinoma cells. For this purpose, the presence of COX-2 and PPARgamma was immunohistochemically examined in 71 epithelial ovarian carcinomas, 18 borderline tumours and 23 benign tumours and the levels of COX-2 and PPARgamma proteins were determined by enzyme immunoassay in four benign tumours, three borderline tumours and 12 carcinomas. The frequency of COX-2 and PPARgamma detection was significantly increased and decreased as lesions progressed to carcinoma, respectively. The COX-2 protein was not detected in the three borderline tumours, whereas PPARgamma protein was detected in all of them. COX-2 protein was detected in eight of the 12 carcinomas, whereas PPARgamma protein was detected in only two cases. In addition, PPARgamma protein was not detected in all of the eight carcinomas in which COX-2 protein was detected, suggesting that expression of PPARgamma and COX-2 was in a reciprocal relationship. Furthermore, in cultured ovarian carcinoma cells, Western blot revealed that PPARgamma and COX-2 expression was regulated conversely as a result of stimulation by 15-deoxy-Delta(12, 14) PGJ(2) (15-PGJ(2)), a PPARgamma activator. In addition, 15d-PGJ(2) suppressed tumour necrosis factor-alpha-induced-COX-2 expression, confirming the reciprocal correlation between COX-2 and PPARgamma. From these results, it was suggested that PPARgamma activation might suppress COX-2 expression via the nuclear factor-kappaB pathway in the ovarian carcinoma cells and that low expression of PPARgamma and high expression of COX-2 might be involved in carcinogenesis and progression of ovarian tumours.

u-PA expression in benign, borderline and malignant ovarian tumors.

The malignant potential of solid tumors is related to their ability to invade adjacent tissue and to metastasize. The plasminogen activation system is one of the critical factors in tumor progression since it is involved in tumor invasion and metastasis. This study was performed to examine the expression of u-PA in benign, borderline and malignant tumors of the ovary by immunohistochemical evaluation on formalin-fixed, paraffin-embedded specimens applying monoclonal antibody 3689 directed to the b-chain of u-PA. Normal epithelial cells of the ovary (n = 5) showed no staining of u-PA but some stromal cells were slightly stained. Invasive carcinomas (n = 16) and borderline tumors (n = 15) showed a moderate to strong diffuse cytoplasmic staining. Benign tumors (n = 20) showed a variety of staining. The observation of randomly positive u-PA stromal cells is noteworthy. The percentage of u-PA-positive tumors was higher in carcinomas than in other tumors. There was no correlation with other known risk factors of malignancy such as differentiation, stage or type of tumor. In conclusion there are noticeable differences in u-PA expression among ovarian tumors and u-PA increase in ovarian tumors can be attributed to an increased diffuse cytoplasmic content in the neoplastic epithelial cells.

Expression of cyclooxygenase-2 and inducible nitric oxide synthase in human ovarian tumors and tumor-associated macrophages.

This study investigates whether and to what extent cyclooxygenase type-2 (COX-2) and inducible nitric oxide-synthase (iNOS), both known to have an immunosuppressive effect, are expressed in human ovarian tumors. Because COX-2 and iNOS can be expressed by activated macrophages, the presence of tumor-associated macrophages and the expression of COX-2 and iNOS by these tumor-associated macrophages were determined. The results obtained may provide insight into the function of COX-2 and iNOS expression by tumors. The expression of COX-2 and iNOS in tumor cells and macrophages was assessed in 18 malignant, 15 borderline, and 14 benign human ovarian tumors by immunohistochemical staining of frozen tissue sections. The intra- and peritumoral macrophages were stained using an anti-CD68 monoclonal antibody. Most of the malignant tumors (15 of 18), 10 of 15 borderline, and 9 of 14 benign tumors showed COX-2 expression in the epithelial cells, a result which indicates that COX-2 expression is not exclusive to malignancy. In addition, COX-2 staining was more intense in the epithelial cells of benign and borderline tumors than in malignant tumors. Weak iNOS staining was observed in 5 of 18 malignant, 4 of 15 borderline, and 5 of 14 benign tumors. The number of tumor-associated macrophages varied widely between the different tumors. The highest number of tumor-associated macrophages (> or =20/0.125 mm(2)) was observed in malignant tumors, whereas low to moderate intra- and peritumoral macrophage infiltration (5-20/0.125 mm(2)) was observed in the borderline and benign tumors. COX-2-positive tumor-associated macrophages were found in 3 of 18 malignant tumors, 7 of 15 borderline tumors, and 1 of 14 benign tumors. The number of COX-2-positive tumor-associated macrophages ranged from 3 to 30% of the total macrophage population. Some malignant (4 of 18), borderline (5 of 15), and benign (2 of 14) tumors contained iNOS-positive macrophages. Notable was that COX-2- and iNOS-positive macrophages were predominantly located in the tumor stroma, the regions between tumor and stroma, and in the lumina of the tumor when located in the tumor tissue. These data indicate that not only malignant but also borderline and benign ovarian tumors can exhibit increased levels of COX-2 and iNOS expression. In addition, a small proportion of the tumor-associated macrophages found in malignant, borderline, and benign tumors seems to be in an activated state, judged by their iNOS and COX-2 expression. This subpopulation of tumor-associated macrophages was invariably located in the tumor stroma or in the lumina of the tumor, specifically suggesting that macrophages outside the tumor can be tumor cytotoxic.

Expression of 5alpha-reductases in human epithelial ovarian cancer: its correlation with androgen receptor status.

Androgen metabolism and possible actions are considered to play some roles in human epithelial ovarian neoplasms, but the details have not been well studied. We have examined the expression of 5alpha-reductase type 1 and type 2, which catalyze the conversion of testosterone to more active androgen, 5alpha-dehydrotestosterone, and androgen receptor (AR), using immunohistochemistry (104 cases) and reverse transcription-polymerase chain reaction (RT-PCR) (16 cases) as a first step toward understanding the metabolism and possible actions of androgens in human common epithelial ovarian carcinoma. 5alpha-Reductase type 1 was immunopositive in 75 / 104 cases (72.0%), and 5alpha-reductase type 2 in 52 / 104 cases (50.0%) (P < 0.001). There was no significant correlation between patterns of immunolocalization and clinicopathological parameters examined. Median labeling index (LI) for AR was 17.8% (range 0 - 84.4%) which was significantly higher in serous carcinoma than other histological types (P < 0.001). There was a significant positive correlation between 5alpha-reductase type 1 immunoreactivity and AR LI (P = 0.0027), but no significant correlation was detected in 5alpha-reductase type 2. Results of RT-PCR analysis were also consistent with those of immunohistochemistry. The relatively wide distribution of 5alpha-reductase type 1, and its correlation to AR status in human epithelial ovarian malignancies suggest that this isozyme plays important roles in androgen metabolism and actions in these tumors.

The levels of trypsinogen isoenzymes in ovarian tumour cyst fluids are associated with promatrix metalloproteinase-9 but not promatrix metalloproteinase-2 activation.

Proteolysis mediated by matrix metalloproteinases (MMPs) and serine proteinases is associated with cancer invasion and metastasis. Activation of latent proMMPs, and especially the proforms of the type IV collagen degrading gelatinases A and B (proMMP-2 and proMMP-9), is thought to be a critical step in this process. We have recently found that human tumour-associated trypsin-2 is a potent activator of proMMP-9 and it also activates proMMP-2 in vitro. Trypsinogen, MMP-2, and MMP-9 are expressed in ovarian cancer. To elucidate the function of trypsin in vivo, we studied whether high concentrations of trypsinogen-1, trypsinogen-2, their alpha(1)-proteinase inhibitor (API) complexes, and tumour-associated trypsin inhibitor (TATI) are associated with proMMP-2 and proMMP-9 activation in ovarian tumour cyst fluids. Zymography and immunofluorometric analysis of 61 cyst fluids showed a significant association between high trypsin concentrations and the activation of MMP-9 (P = 0.003-0.05). In contrast, the trypsin concentrations were inversely associated with the activation of MMP-2 (P = 0.01-0.02). Immunohistochemical analysis of ovarian tumour tissue demonstrated expression of trypsinogen-2 and TATI in the secretory epithelium. MMP-2 was detected both in stromal and epithelial cells whereas MMP-9 was detected in neutrophils and macrophage-like cells in stromal and epithelial areas. These results suggest that trypsin may play a role in the regulation of the MMP-dependent proteolysis associated with invasion and metastasis of ovarian cancer.

A gonadotropin-releasing hormone-responsive phosphatase hydrolyses lysophosphatidic acid within the plasma membrane of ovarian cancer cells.

Lysophosphatidic acid (LPA) mediates pleomorphic effects on multiple cell lineages, including an increased proliferative response of ovarian cancer cells both in vitro and in vivo, at least in part through the novel expression of LPA receptors. Thus, LPA hydrolysis is necessary to limit the duration of LPA's action on multiple cell types, including ovarian cancer cells. We determined the principal mechanism of LPA hydrolysis by ovarian cancer cells and its regulation by GnRH, which is known to have antiproliferative actions on ovarian carcinomas. LPA-hydrolyzing activity in cell membranes of ovarian cancer specimens was assessed by measuring the conversion of exogenous [3H-oleoyl]LPA to [3H]oleic acid or mono[3H-oleoyl]glycerol. Approximately 98% of LPA hydrolysis could be accounted for by the dephosphorylation of LPA to yield monoglyceride, with the deacylation reaction accounting for less than 1% of LPA hydrolysis. The phosphatase activity in the plasma membrane ovarian cancer cells was approximately 2.5- and 8-fold higher than those in microsome and homogenate fractions, respectively. The membrane phosphatase was Mg2+ independent and insensitive to inhibition by N-ethylmaleimide, characteristics suggestive of phosphatidic acid phosphatase activity. Incubation of membranes from GnRH receptor-positive ovarian cancer specimens with the GnRH agonist, buserelin, induced a dose-dependent increase in LPA phosphatase activity, with a half-maximal effect occurring with 30 nmol/L buserelin. The stimulatory action of buserelin could be neutralized by displacement of GnRH from its receptor by the GnRH antagonist, antide. The plasma membranes from GnRH receptor-negative ovarian cancer specimens did not respond to GnRH stimulation. LPA phosphatase activity was also increased when the ovarian cancer cell line Caov-3 was exposed to GnRH agonist in intact cells before assay of cell membranes. These data demonstrate that LPA is hydrolyzed in the plasma membrane of ovarian cancer cells by the action of LPA phosphatase and provide initial evidence for functional coupling of LPA phosphatase to GnRH receptor occupancy.

Expression of matrix metalloproteinases and related tissue inhibitors in the cyst fluids of ovarian mucinous neoplasms.

OBJECTIVES AND METHODS: The growth of an ovarian cystic neoplasm often involves its invasion into and destruction of the extracellular matrix. We examined neoplastic cysts of ovarian mucinous tumors for the presence of matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMPs) using zymography (in situ zymography, gelatin zymography, and casein zymography) and enzyme-linked immunosorbent assay. RESULTS: Matriolytic activity was detected within the cystic contents and cytoplasm of the lining epithelial cells of the cyst by in situ zymography. This intracystic matriolytic activity was thought to originate mainly in the epithelial cells. The activated form of MMP-9 was seen in all carcinoma and borderline fluids and in 7 of 15 adenomas. The concentration of MMP-9 was higher in carcinoma fluids than in borderline and adenoma fluids (P < 0.05). TIMP-1, which specifically binds to MMP-9, was also higher in carcinoma and borderline fluids than in adenoma fluids (P < 0.05). MMP-2 activity was nearly ubiquitously present in all cyst fluids, irrespective of the fluid's histologic category. The amount of MMP-2 was highest in the carcinoma category, although not to a statistically significant degree. TIMP-2, a specific inhibitor for MMP-2, was significantly lower in the borderline category than in the adenoma category. The molar ratios of TIMP-1/MMP-9 (not significant) and TIMP-2/MMP-2 (P < 0.05) were higher in the adenoma category. Expressions of trypsin, MMP-7, and MMP-9 were generally higher in carcinoma and borderline fluids than in adenoma fluids. CONCLUSIONS: These observations indicate the importance of ovarian cystic fluids for analyzing tumor-associated matriolytic activities. The findings suggest that these matriolytic enzymes, together with the presence of their inhibitors, play an important role in the growth of ovarian mucinous tumors.

Differential expression of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 protein and mRNA in epithelial ovarian tumors.

OBJECTIVE: Matrix metalloproteinase-9 (MMP-9) can degrade gelatin and type IV collagen and is known to play an important role in tumor cell invasion across the basement membrane. The tissue inhibitor of metalloproteinase-1 (TIMP-1) is able to prevent activation of pro-MMP-9 and forms a 1:1 complex with the active form of MMP-9. The aim of the present study was to investigate the expression of MMP-9 and TIMP-1 in benign, borderline, and invasive epithelial ovarian tumors. MATERIALS AND METHODS: A total of 90 patients with epithelial ovarian tumor were treated at the Brigham and Women's Hospital and were used as the study population. Immunohistochemistry and in situ hybridization were performed to detect protein and mRNA expression of MMP-9 and TIMP-1. RESULTS: In the 90 epithelial ovarian tumors tested, MMP-9 expression in tumor cells was found to be significantly enhanced in serous and mucinous ovarian carcinomas compared with benign and borderline tumors. We also observed the immunostaining of MMP-9 in stromal cells of benign, borderline, and invasive epithelial ovarian tumors. Moreover, the expression levels of TIMP-1 in tumor cells were significantly higher in borderline and invasive ovarian tumors than in benign tumors. CONCLUSION: Using an in situ hybridization technique, we disclosed a direct correlation between the presence of mRNA and protein expression for both MMP-9 and TIMP-1. The present data suggest that high levels of MMP-9 protein in invasive epithelial ovarian carcinoma are strongly associated with tumor cell invasion. Enhanced expression of TIMP-1 protein in borderline and invasive tumors indicates that endogenous TIMP-1 protein may play a paradoxical role in ovarian tumor progression.

Induction of matrix metalloprotease-7 is common in mucinous ovarian tumors including early stage disease.

Matrix metalloproteases are known to play an important role in tumor invasion by mediating degradation of the extracellular matrix. In this study, we have investigated the immunohistochemical expression of matrix metalloprotease -7 (MMP-7) in 44 mucinous ovarian tumors (9 adenomas, 13 low malignant potential tumors, 22 adenocarcinomas) and 6 normal ovaries. Positive staining of MMP-7 is observed in all mucinous ovarian tumors, whereas little or no staining was observed in surface epithelium as well as the epithelial cells of germinal inclusion cyst of the normal ovary. Positive immunostaining of MMP-7 is also observed in the secreted mucin in the tumor glands, which suggests the secretion of the MMP-7 protein from tumor cells. mRNA expression of MMP-7 was confirmed using RT-PCR. The MMP-7 gene was amplified in parallel with an internal control gene beta-tubulin using a thermal cycler. mRNA expression levels of MMP-7 were significantly elevated in mucinous tumor samples compared with that in normal ovaries. Our results suggest that MMP-7 is frequently overexpressed in mucinous ovarian tumors and secreted with the mucin which is produced from the tumor cells. MMP-7 may therefore contribute to mucinous ovarian tumor development or enhanced growth capacity of mucinous ovarian tumors. MMP-7 may also serve as a target for therapeutic intervention in the down regulation of tumor progression.

Telomerase activity is a useful marker to distinguish malignant pancreatic cystic tumors from benign neoplasms and pseudocysts.

BACKGROUND: Pancreatic serous cystadenoma, mucinous cystic neoplasms, ductal adenocarcinoma with cystic change, and pseudocysts are a spectrum of pancreatic cystic lesions. Their management strategy and prognosis are extremely diverse. Imaging study, cytology, and analysis of the tumor markers of cyst fluid are not always reliable in differentiation of these disease entities. MATERIALS AND METHODS: Fifteen patients with pancreatic cystic neoplasms (including six mucinous cystadenocarcinomas, two mucinous cystic neoplasms with borderline malignancy, two mucinous cystadenomas, and five serous cystadenomas), 4 patients with pancreatic ductal adenocarcinomas with cystic change, and 10 patients with pseudocysts were studied. Echo-guided or computed tomography-guided biopsies of pancreatic cystic lesions and their normal counterparts were conducted on all patients prior to operation or other management. The specimens were assayed for telomerase activity by using TRAP (telomere repeat amplification protocol). The level of telomerase activity in each specimen was semiquantitated as strong, moderate, weak, and none. The final diagnoses were made from histopathological examination of surgically resected or biopsied specimens. The efficacy of telomerase activity as a tumor marker to predict malignancy of pancreatic cystic lesions was evaluated. RESULTS: Three of the four pancreatic ductal adenocarcinomas with cystic change had strong or moderate telomerase activity; four of the six mucinous cystadenocarcinomas had moderate or weak telomerase activity; one of the two mucinous cystadenomas with borderline malignancy had weak telomerase activity; and none of their normal counterparts had detectable telomerase activity. In contrast, none of the two mucinous cystadenomas, five serous cystadenomas, and 10 pseudocysts had detectable telomerase activity. Based on these results, the sensitivity of telomerase activity for prediction of malignancy or premalignancy of pancreatic cystic lesions was 67%, the specificity was 100%, and the positive and negative predictive values were 1.0 and 0.81, respectively. The overall accuracy was 86%. CONCLUSIONS: The differential expressions of telomerase activity have been detected specifically in malignant and premalignant pancreatic cystic tumors, but not in benign cystic neoplasms or pseudocysts. The implications of these results are that telomerase activation takes part in the malignant transformation of pancreatic cystic neoplasms and that telomerase activity is a useful marker to distinguish malignant pancreatic cystic tumors from benign neoplasms and pseudocysts.

Effects of sex steroids and growth factors on invasive activity and 5'-deoxy-5-fluorouridine sensitivity in ovarian adenocarcinoma OMC-3 cells.

Effects of sex steroids (estradiol-17 beta, E2; progesterone, Prog) and growth factors (epidermal growth factor, EGF; transforming growth factor-alpha, TGF-alpha) on invasive activity and 5'-deoxy-5-fluorouridine (5'-dFUrd) sensitivity of ovarian adenocarcinoma OMC-3 cells were investigated. Tumor cell migration along a gradient of substratum-bound fibronectin and invasion into reconstituted basement membrane were inhibited by 10 microM Prog, but stimulated by 0.1-10 nM EGF and TGF-alpha in a concentration-dependent manner. E2 did not have any effect on tumor cell migration or invasion. The zymography of tumor conditioned medium showed that the treatment of OMC-3 cells with EGF and TGF-alpha resulted in increases of type IV collagenase, stromelysin and urokinase-type plasminogen activator (uPA). EGF and TGF-alpha up-regulated thymidine phosphorylase (dThdPase) expression of tumor cells and consequently enhanced the antiproliferative action of 5'-dFUrd, which is converted to 5-fluorouracil by dThdPase. E2 and Prog did not have significant effects on the expression of proteolytic enzymes and dThdPase, or on the 5'-dFUrd sensitivity of tumor cells. The inhibitory effect of Prog on tumor cell invasion may depend on its inhibitory action on the motility of tumor cells. These results suggest that EGF and TGF-alpha simultaneously up-regulate the potential of ovarian adenocarcinoma cells to invade extracellular matrices and their dThdPase expression, both of which are associated with the specific action of 5'-dFUrd selectively to kill tumor cells with high invasive and metastatic potential.

Peritoneal fluid lactate dehydrogenase in ovarian cancer.

In attempt to identify patients with ovarian carcinoma and differentiate them from patients with benign ovarian tumor or other gynecological malignancies, peritoneal fluid and serum lactate dehydrogenase (LDH) levels were measured in 51 patients: 15 with ovarian carcinoma, 15 with endometrial carcinoma, 4 with cervical carcinoma, and 17 with benign ovarian tumor. Peritoneal fluid and serum LDH levels in ovarian cancer patients were significantly higher than those in patients with benign ovarian tumor (P < 0.001) or other gynecological malignancies (P < 0.001 and P < 0.03, respectively). Yet, peritoneal fluid LDH demonstrated higher diagnostic sensitivity (87%) and greater diagnostic accuracy (90%) than serum LDH (60 and 77%, respectively) or serum CA-125 (73 and 83%, respectively). Comparing the histological types of ovarian cancer, serous cystadenocarcinoma presented higher peritoneal fluid LDH levels than endometrioid or mucinous cystadenocarcinoma. No difference in peritoneal fluid LDH was observed comparing different stages of ovarian cancer. The results suggest that peritoneal fluid LDH may be an efficient biochemical marker in diagnosis of ovarian cancer.

[Expression of glutathione S-transferase-pi in operative specimens as marker of chemoresistance in patients with ovarian cancer].

OBJECTIVE: To study the relationship between the expression of glutathione S-transferase-pi (GST-pi) in operative specimens and chemoresistance in patients with ovarian cancer. METHODS: The expression of GST-pi in 87 epithelial ovarian cancer tissues and 30 normal ovarian epithelial tissues was determined with labelled streptavidin biotin method (LSAB). All the patients had not received chemotherapy before operation. We used Chi-Square and Cox-Mantel test to analyze the relativity between the expression of GST-pi and clinical pathological data, chemotherapeutic response, prognosis in patients with ovarian cancer. RESULTS: (1) 59 (67.8%) of 87 ovarian cancer tissue were demonstrated to be positive expression with GST-pi, but all 30 normal ovarian epithelial tissue were negative. (2) There was no direct correlation between the expression of GST-pi and clinical pathological data. (3) 43 (43/59) of GST-pi positive cases were chemoresistant, while only 3 (3/28) of GST-pi negative ones were chemoresistant. (4) The difference in the chemotherapeutic response between the two groups was obviously significant (P < 0.005). The survival period of the patients with GST-pi positive expression was also obviously shorter than that of those with GST-pi negative expression (P = 0.004). CONCLUSION: These results strongly suggest that GST-pi expression in epithelial ovarian cancer tissues is closely related to chemoresistance clinically and it may be served as a useful marker to predict the prognosis of patients.