Urinary angiostatin levels are elevated in patients with epithelial ovarian cancer.

OBJECTIVE: The poor prognosis associated with epithelial ovarian cancer (EOC) is due to the lack of overt early symptoms and the absence of reliable diagnostic screening methods. Since many tumors over express angiogenic regulators, the purpose of this study was to determine whether elevated levels of the angiogenic or angiostatic molecules vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), endostatin (ES), and angiostatin (AS) were elevated in plasma and urine from patients with EOC. METHODS: VEGF, HGF, ES and AS were assayed by ELISA in samples from pilot cohort consisting of healthy women (N=48; pre-menopausal N=23, post-menopausal N=25), women with benign gynecological disease (N=54), patients with primary peritoneal cancer (PP) (N=2) and EOC (N=35). Wherever possible, parallel serum samples were measured for CA125 levels by ELISA. RESULTS: AS was the angioregulator that independently discriminated EOC patients from healthy individuals. Levels of urinary AS (uAS) from healthy individuals or women with benign gynecological disease averaged 21.4 ng/mL+/-3.7 and 41.5 ng/mL+/-8.8, respectively. In contrast, uAS averaged 115 ng/mL+/-39.2 and 276 ng/mL+/-45.8 from women with Stage I (N=6) and late stage (N=31) EOC, respectively. Furthermore, uAS was elevated in EOC patients regardless of tumor grade, stage, size, histological subtype, creatinine levels, menopausal status, or patient age, but appeared to complement CA125 measurements. CONCLUSIONS: Levels of AS are elevated in the urine of patients with EOC and may be of diagnostic and/or prognostic clinical importance. Further studies of uAS as a biomarker for EOC alone or in combination with other markers are warranted.

Aberrant regulation of argininosuccinate synthetase by TNF-alpha in human epithelial ovarian cancer.

The pro-inflammatory cytokine, tumour necrosis factor-alpha, TNF-alpha, is dysregulated in malignant compared with normal ovarian surface epithelium (OSE). Several epidemiological studies have associated inflammation with ovarian tumorigenesis, with TNF-alpha playing a key role in modulating invasion, angiogenesis and metastasis. Here, we show that TNF-alpha also induces expression of arate-limiting enzyme in arginine synthesis, argininosuccinate synthetase (AS), thereby linking inflammation with several arginine-dependent metabolic pathways, implicated in accelerated carcinogenesis and tumour progression. Having identified AS mRNA induction in TNF-alpha-treated IGROV-1 ovarian cancer cells, using RNA-arbitrarily primed-PCR, we then observed differential regulation of AS mRNA and protein in malignant, compared with normal, OSE cells. A cDNA cancer profiling array with matched normal ovarian and ovarian tumour samples revealed increased expression of AS mRNA in the latter. Moreover, AS protein co-localised with TNF-alpha in ovarian cancer cells, with significantly higher levels of AS in malignant compared with normal ovarian tissue. Increased co-expression of AS and TNF-alpha mRNA was also observed in 2 other epithelial tumours, non-small cell lung and stomach cancer, compared with normal corresponding tissues. In summary, high levels of AS expression, which may be required for several arginine-dependent processes in cancer, including the production of nitric oxide, proline, pyrimidines and polyamines, is regulated by TNF-alpha and may provide an important molecular pathway linking inflammation and metabolism to ovarian tumorigenesis.

Expression and regulation of tumor necrosis factor alpha in normal and malignant ovarian epithelium.

Epidemiologic studies implicate inflammatory stimuli in the development of ovarian cancer. The proinflammatory cytokine tumor necrosis factor alpha (TNF-alpha) and both its receptors (TNFRI and TNFRII) are expressed in biopsies of this malignancy. Here, we tested the hypothesis that TNF-alpha is a regulator of the proinflammatory microenvironment of ovarian cancer. A cancer profiling array showed higher expression of TNF-alpha in ovarian tumors compared with normal ovarian tissue, and cultured ovarian cancer cells expressed up to 1,000 times more TNF-alpha mRNA than cultured normal ovarian surface epithelial cells; TNF-alpha protein was only detected in the supernatant of tumor cell cultures. Treatment with TNF-alpha induced TNF-alpha mRNA via TNFRI in both malignant and normal cells with evidence for enhanced TNF-alpha mRNA stability in tumor cells. TNF-alpha induced TNF-alpha protein in an autocrine fashion in tumor but not in normal ovarian surface epithelial cells. The TNF-alpha neutralizing antibody infliximab reduced the constitutive levels of TNF-alpha mRNA in tumor cell lines capable of autocrine TNF-alpha production. Apart from TNF-alpha mRNA expression, several other proinflammatory cytokines were constitutively expressed in malignant and normal ovarian surface epithelial cells, including interleukin (IL)-1alpha, IL-6, CCL2, CXCL8, and M-CSF. TNF-alpha treatment further induced these cytokines with de novo transcription of IL-6 mRNA contrasting with the increased stability of CCL2 mRNA. RNA interference directed against TNF-alpha was highly effective in abolishing constitutive IL-6 production by ovarian tumor cells. In summary, we show that TNF-alpha is differentially regulated in ovarian cancer cells compared with untransformed cells and modulates production of several cytokines that may promote ovarian tumorigenesis. Infliximab treatment may have a role in suppressing the TNF-alpha-driven inflammatory response associated with ovarian cancer.

BRCA1 and BRCA2 mutations account for a large proportion of ovarian carcinoma cases.

BACKGROUND: It is believed that BRCA1 and BRCA2 germline mutations account for the majority of hereditary ovarian carcinomas; however, to the authors' knowledge, there are scant data on the prevalence and spectrum of mutations, genotype/phenotype correlations, tumor histology, and family history characteristics. To address this gap, the authors conducted a population-based study of 232 incident epithelial ovarian carcinomas in the Tampa Bay area. METHODS: Genetic testing for the BRCA1 and BRCA2 genes was performed through full sequencing and BRCA1 rearrangement testing. RESULTS: Of 209 women with invasive ovarian carcinoma, 32 women (15.3%) had mutations in BRCA1 or BRCA2, including 20 BRCA1 mutations and 12 BRCA2 mutations. Of the BRCA2 mutations, 58% were outside the "ovarian cancer cluster region" (OCCR). Variants of uncertain significance were detected in 8.2% of women with invasive ovarian carcinoma. No mutations were identified in women with borderline or invasive mucinous tumors. Among the BRCA mutation-positive women, 63% had serous tumors. A family history of breast and/or ovarian carcinoma was reported in 65%, 75%, and 43.5% of relatives of BRCA1 carriers, BRCA2 carriers, and non-BRCA1/BRCA2 carriers, respectively. CONCLUSIONS: The data from this study suggested that 1) previous studies may have underestimated the frequency of BRCA1 and BRCA2 mutations in ovarian carcinomas, especially outside the OCCR; 2) it may be reasonable to offer genetic counseling to any woman with an invasive, nonmucinous epithelial ovarian tumor; and 3) among patients with invasive ovarian carcinoma, family history is not sufficiently accurate to predict mutation status.

Lysophospholipids are potential biomarkers of ovarian cancer.

OBJECTIVE: To determine whether lysophosphatidic acid (LPA) and other lysophospholipids (LPL) are useful markers for diagnosis and/or prognosis of ovarian cancer in a controlled setting. METHOD: Plasma samples were collected from ovarian cancer patients and healthy control women in Hillsborough and Pinellas counties, Florida, and processed at the University of South Florida H. Lee Moffitt Cancer Center and Research Institute (Moffitt). Case patients with epithelial ovarian cancer (n = 117) and healthy control subjects (n = 27) participated in the study. Blinded LPL analysis, including 23 individual LPL species, was performed at the Cleveland Clinic Foundation using an electrospray ionization mass spectrometry-based method. LPL levels were transmitted to Moffitt, where clinical data were reviewed and statistical analyses were performed. RESULTS: There were statistically significant differences between preoperative case samples (n = 45) and control samples (n = 27) in the mean levels of total LPA, total lysophosphatidylinositol (LPI), sphingosine-1-phosphate (S1P), and individual LPA species as well as the combination of several LPL species. The combination of 16:0-LPA and 20:4-LPA yielded the best discrimination between preoperative case samples and control samples, with 93.1% correct classification, 91.1% sensitivity, and 96.3% specificity. In 22 cases with both preoperative and postoperative samples, the postoperative levels of several LPL, including S1P, total LPA, and lysophosphatidylcholine (LPC) levels and some individual species of LPA and LPC, were significantly different from preoperative levels. CONCLUSION: LPA, LPI, LPC, and S1P appear useful as diagnostic and prognostic biomarkers of ovarian cancer.

A modified medium that significantly improves the growth of human normal ovarian surface epithelial (OSE) cells in vitro.

Approximately 90% of malignant ovarian tumours are epithelial and thought to arise from a single cell layer, the ovarian surface epithelium. In culture, human normal ovarian surface epithelial (OSE) cells have a very limited lifespan before they senesce, rarely progressing beyond 10 population doublings. This has restricted the use of normal OSE cells for studying the biology of ovarian surface epithelium and identifying molecular events that contribute to malignant transformation. We have investigated the conditions for culturing human, normal OSE cells in vitro using modified media. Culturing normal OSE cells in a modified medium (NOSE-CM) supplemented with epidermal growth factor, hydrocortisone, insulin and bovine pituitary extract led to significant improvements in the seeding and cloning efficiencies, overall cell growth and lifespan compared to culturing in a basic, nonsupplemented medium (BM) and previously used media (F-12 K medium and William's medium E). Cells cultured in NOSE-CM underwent, on an average, 19.0 population doublings (95% CI 16.3-21.7); cells cultured in BM underwent 0.43-3.52 population doublings over a similar time period. Growth curves established for different lines indicated that OSE cells continued to grow beyond passage 11 and up to passage 18 in NOSE-CM, but never beyond passage 7 when cultured in BM. It is likely that establishing optimal conditions for the growth of OSE cells in vitro will enable studies of the biological and genetic mechanisms of transformation in epithelial ovarian cancers.

Insulin-like growth factors, insulin-like growth factor-binding proteins, and endometrial cancer in postmenopausal women: results from a U.S. case-control study.

OBJECTIVE: To assess whether circulating insulin-like growth factor-1 (IGF-1), IGF-2, insulin-like growth factor-binding protein-1 (IGFBP-1), or IGFBP-3 were associated with endometrial cancer in postmenopausal women. STUDY DESIGN: Between 1987 and 1990, we conducted a case-control study of 405 women with endometrial cancer and 297 matched population-based controls. This analysis included 174 postmenopausal cases and 136 controls. RESULTS: In logistic regression models adjusted for potential confounders, higher IGF-1 levels were not positively associated with endometrial cancer: odds ratio (OR) for the highest tertile versus the lowest tertile = 0.63, 95% confidence interval (CI) = 0.30-1.32. Endometrial cancer was inversely associated with IGF-2 (OR for the highest tertile = 0.35, 95% CI = 0.18-0.69) and IGFBP-3 (OR for the highest tertile = 0.40, 95% CI = 0.21-0.77), and not associated with IGFBP-1. CONCLUSION: Serum IGF-1, IGF-2, and IGFBP-3, but not IGFBP-1, were inversely associated with endometrial cancer in postmenopausal women. These associations and the potential role of the IGF system in endometrial proliferation and carcinogenesis warrant further research.

Cytology of human ovarian surface epithelial brushings.

BACKGROUND: The human ovarian surface epithelium (HOSE) is the putative source of ovarian epithelial cancer, the most lethal gynecologic malignancy that affects women in the United States. The current study was designed to provide a database of normal HOSE cell features for diagnostic and research applications. METHODS: HOSE was harvested from 42 women undergoing laparoscopy or laparotomy for benign gynecologic disorders, infertility problems, or pregnancy. Of the 42 women, 12 were postovulatory and 20 were receiving hormonal regimens. Cells were harvested with a sterile brush inserted through a laparoscopic port or with a sterile cell scraper at laparotomy. RESULTS: Two HOSE populations were identified, ranging in size from 8 to 10 microm and from 15 to 20 microm, respectively. The cells measuring 15-20 microm exhibited slight anisonucleosis, more prominent nucleoli, fine cytoplasmic metachromasia, and an overall reparative or squamoid morphology. Cells were single or arranged in small clusters, sheets, or papillae. They coexpressed cytokeratin and vimentin but did not overexpress p53. Cellularity and proliferation (up to 3.2% +/- 0.8) were higher and papillae more frequent in postovulatory and cyst-bearing ovaries, including polycystic ovaries, suggesting underlying ovarian or hormonal influences. Representative HOSE brushings yielded a mean of 23,133 cells per patient (range, 4250-64,500 cells), equivalent to an estimated 0.58, 0.46, and 0.14 microg of nuclear protein, cell RNA, and nuclear DNA, respectively. Within 7-10 days of explantation, HOSE cells formed confluent monolayers with immunohistochemical and ultrastructural epithelial features. CONCLUSIONS: The current study defined baseline features of HOSE cells important to pathologists and clinicians evaluating women at risk for ovarian epithelial cancer and to researchers investigating the pathobiology of this aggressive gynecologic malignancy.

Molecular assessment of depth of myometrial invasion in stage I endometrial cancer: a model based on K-ras mutation analysis.

INTRODUCTION: Overall nearly 20% of endometrial cancer (EC) patients die of the disease and over half of these had initially presented with clinical stage I disease. There is a strong correlation between disease mortality and depth of myometrial invasion. Current assessment of depth of invasion relies on light microscopy. Tumor cells can evade detection by light microscopy if they are vastly outnumbered by myometrial cells. Molecular techniques have a great potential in the detection of such isolated cells. OBJECTIVE: The objective was to develop a model for the application of molecular techniques to advance the assessment of risk status in patients with clinical stage I EC. METHODS: The study sample included 21 stage I ECs with a documented K-ras mutation from two series of 96 and 106 ECs from the United Kingdom and Norway, respectively. K-ras was documented using heteroduplex mobility analysis and amplified created restriction site, followed by sequencing to identify the specific base substitution at codon 12 and 13 of K-ras oncogene. For each case with a K-ras mutation, a modified mutant allele-specific amplification technique was carried out on a series of tissue strips microdissected at increasing depths from the myometrium underlying tumor. The microdissected myometrium had been previously examined histologically for absence of infiltrating tumor cells on light microscopy. Presence of K-ras mutations was used to identify the tumor cells within the histologically normal myometrium. Correlations between submicroscopic myometrial tumor cell infiltration and clinicopathological factors were studied. RESULTS: Of 21 cases with K-ras mutation, 6 cases (28%) showed molecular evidence of tumor cell infiltration beyond the histological boundary. The depth of submicroscopic myometrial infiltration was found to be variable. The staging of the tumors would have changed in 3 cases (14%) if tumor cells been detected histologically. A borderline significant correlation between presence of submicroscopic myometrial invasion and depth of myometrial invasion was noted (P = 0.053). The recurrence rate and survival of patients without submicroscopic invasion were better than those with, although it did not reach statistical significance (recurrence rate P = 0.13, recurrence free survival P = 0.14, cause-specific survival P = 0.12, and total survival P = 0.2). CONCLUSIONS: Molecular assessment of depth of myometrial invasion using K-ras mutation is feasible and may add information to conventional light microscopy. Further prospective studies are required to define the clinical significance of this technology.

Multiple actions of the chemokine CXCL12 on epithelial tumor cells in human ovarian cancer.

Of 14 chemokine receptors investigated, only CXCR4 was expressed on ovarian cancer cells [C. J. Scotton et al., Cancer Res., 61: 4961-4965, 2001]. To further understand the role of this chemokine receptor in ovarian tumor biology, we studied the action of its ligand, CXCL12 (stromal cell-derived factor 1), on the CXCR4-expressing ovarian cancer cell lines IGROV. Ligand stimulation of the CXCR4 receptor resulted in sustained activation of Akt/protein kinase B and biphasic phosphorylation of p44/42 mitogen-activated protein kinase in IGROV. When IGROV cells were cultured under suboptimal conditions, CXCL12 stimulated their in vitro growth, an effect that was abrogated by neutralizing antibodies to CXCR4. This increase in cell number was attributable to stimulation of DNA synthesis, not protection from apoptosis. CXCL12 treatment of IGROV cells also induced mRNA and protein for tumor necrosis factor alpha, a cytokine that is expressed by tumor cells in ovarian cancer biopsies. IGROV cells invaded through Matrigel toward a CXCL12 gradient. Invasion was abrogated by the broad spectrum matrix metalloproteinase and TNFalpha converting enzyme inhibitor Marimastat and was partially inhibited by neutralizing antitumor necrosis factor alpha antibodies. These effects were not limited to the IGROV cell line. They could also be demonstrated in the CAOV-3 ovarian cancer cell line and primary ovarian tumor cells isolated from ovarian ascites. These biological effects of CXCL12 on IGROV cells were also inhibited by the small molecular weight CXCR4 antagonist AMD3100. Finally, we found abundant intracellular CXCL12 protein in tumor cells in 15 of 18 ovarian cancer biopsies but not in epithelial cells from normal ovary or borderline disease. The chemokine CXCL12 may have multiple biological effects in ovarian cancer, stimulating cell migration and invasion through extracellular matrix, as well as DNA synthesis and establishment of a cytokine network in situations that are suboptimal for tumor cell growth.

Insights from gene arrays on the development and growth regulation of uterine leiomyomata.

OBJECTIVE: To use microarray analysis as an unbiased approach to identify genes involved in the induction and growth of uterine leiomyomata. DESIGN: Screen by arrays for up to 12,000 genes in leiomyoma (L) and control myometrium (M) from nine patients. SETTING: University research laboratories. PATIENT(S): Nine patients in the follicular and luteal phases of the menstrual cycle. INTERVENTION(S): mRNA from L and M was converted to biotin-labeled cRNA and hybridized to cDNA oligonucleotide sequences on the arrays. MAIN OUTCOME MEASURE(S): Greater than two-fold change in gene expression between leiomyoma and matched myometrium. RESULT(S): Prominent among the 67 genes overexpressed in L relative to M were dlk or Pref-1, doublecortin, JM27, ionotropic glutamate receptor subunit 2, apolipoprotein E3, IGF2, semaphorin F, myelin proteolipid protein, MEST, frizzled, CRABP II, stromelysin-3, and TGFbeta3. The genes dlk, IGF2, and MEST are paternally expressed imprinted genes, and the others are involved in tissue differentiation and growth. Prominent among the 78 genes down-regulated in L relative to M were alcohol dehydrogenases 1alpha-gamma, tryptase, dermatopontin, thrombospondin, coxsackievirus receptor, nur77, and c-kit. CONCLUSION(S): Arrays offer large-scale screening of mRNA expression, which will help us differentiate between the genes and metabolic pathways necessary for leiomyoma growth and those regulating myometrial contractions.