To review the current understanding of the underlying molecular, biologic and genetic mechanisms involved in ovarian cancer development and how these mechanisms can be targets for prevention, detection and treatment of the disease and its recurrence.
In May 2012, we convened a meeting of researchers, clinicians and consumer advocates to review the state of current knowledge on molecular mechanisms and identify fruitful areas for further investigations.
The meeting consisted of seven scientific sessions, ranging from Epidemiology, Early Detection, and Biology to Therapeutics and Quality of Life. Sessions consisted of talks and panel discussions by international leaders in ovarian cancer research. A special career-development session by the CDMRP Department of Defense Ovarian Cancer Academy as well as an oral abstract and poster session showcased promising new research by junior scientists.
Technological advances in the last decade have increased our knowledge of the molecular mechanisms involved in a host of biological activities related to ovarian cancer. Understanding the role these mechanisms play in cancer initiation and progression will help lead to the development of prevention and treatment modalities that can be personalized to each patient, thereby helping to overcome this highly-fatal malignancy.
ovarian neoplasms; epidemiology; etiology; screening; biomarkers; proteomics; genomics; metabalomics; BRCA1/2; cancer stem cells; micro RNA; nuclear receptors; individualized medicine; cancer vaccines; quality of life; patient reportable outcomes; therapeutics; clinical trials; survival
Previous studies examining associations between use of fertility drugs and ovarian cancer risk have provided conflicting results. We used data from a large case-control study to determine whether fertility drug use significantly impacts ovarian cancer risk when taking into account parity, gravidity, and cause of infertility.
Data from the Hormones and Ovarian Cancer Prediction (HOPE) study were used (902 cases, 1802 controls). Medical and reproductive histories were collected via in-person interviews. Logistic regression was used to calculate odds ratios (OR) and 95% confidence intervals (CI). Models were adjusted for age, race, education, age at menarche, parity, oral contraceptive use, breastfeeding, talc use, tubal ligation, and family history of breast/ovarian cancer.
Ever use of fertility drugs was not significantly associated with ovarian cancer within the total HOPE population (OR: 0.93, 95%CI: 0.65–1.35) or among women who reported seeking medical attention for infertility (OR: 0.87, 95%CI 0.54–1.40). We did observe a statistically significant increased risk of ovarian cancer for ever use of fertility drugs among women who, despite seeking medical attention for problems getting pregnant, remained nulligravid (OR: 3.13, 95%CI 1.01–9.67).
These results provide further evidence that fertility drug use does not significantly contribute to ovarian cancer risk among the majority of women; however, women who despite infertility evaluation and fertility drug use remain nulligravid, may have an elevated risk for ovarian cancer.
Our results suggest that fertility drug use does not significantly contribute to overall risk of ovarian cancer when adjusting for known confounding factors.
ovarian cancer; fertility drugs; infertility; case-control
CXCL12 is a chemotactic cytokine that has pro-metastatic functions in several malignancies through interactions with its receptor, CXCR4. CXCL12 is an estrogen-regulated gene, and notably, estrogen is a major risk factor for endometrial cancer (EC) development. As few studies examine concurrent CXCL12, CXCR4, and estrogen receptor (ER) expression in EC patients, we examined this pathway in 199 EC patients with data from the University of Pittsburgh Medical Center Cancer Registry. Immunohistochemistry (IHC) was used to detect CXCR4, CXCL12, and ER protein expression. As CXCR4 expression was positive in all cases, this investigation focused on associations between CXCL12 and ER expression, clinicopathologic factors, and survival outcomes using chi-square tests, Kaplan-Meier graphs, and log-rank tests. CXCL12 expression was negative in 63 cases (32%) and positive in 136 cases (68%). Negative CXCL12 expression was borderline significantly associated with metastasis (χ2 p=0.07). ER expression was negative in 75 cases (38%) and positive in 124 cases (62%). Positive ER expression was significantly associated with low grade and early stage tumors (χ2 p<0.001). CXCL12 and ER were not significantly associated (χ2 p=0.11). Positive CXCL12 expression was associated with longer overall survival (OS) (log-rank p=0.006) and longer recurrence-free survival (RFS) (log-rank p=0.01) in ER negative patients, but not in ER positive patients. We identified a unique molecular signature associated with better OS and RFS in EC patients. In addition to pathological characteristics of the tumor, expression of CXCL12 and ER may be clinically useful for assigning adjuvant treatment to EC cases.
clear cell; papillary serous; prognostic biomarkers; chemokines; metastasis
Aspirin, non-aspirin nonsteroidal anti-inflammatory drugs (NA-NSAIDs) and acetaminophen all have biologic effects that might reduce the risk of ovarian cancer. However, epidemiologic data on this question are mixed.
A population-based, case-control study in western Pennsylvania, eastern Ohio, and western New York State included 902 women with incident epithelial ovarian cancer who were diagnosed between February 2003 to November 2008 and 1,802 matched controls. Regular use (at least 2 tablets per week for 6 months or more) of aspirin, NA-NSAIDs, and acetaminophen before the reference date (9 months before interview date) was assessed by in-person interview. We used logistic regression to calculate adjusted odds ratios (ORs) and 95% confidence intervals (CIs).
The OR for aspirin use was 0.81 (95% CI= 0.63–1.03). Decreased risks were found among women who used aspirin continuously (0.71 [0.54–0.94]) or at a low-standardized daily dose (0.72 [0.53–0.97]), who used aspirin for the prevention of cardiovascular disease (0.72 [0.57–0.97]), who used aspirin more recently, or who used selective COX-2 inhibitors (0.60 [0.39–0.94]). No associations were observed among women using non-selective NA-NSAIDs or acetaminophen.
Risk reductions of ovarian cancer were observed with use of aspirin or selective COX-2 inhibitors. However, the results should be interpreted with caution due to the inherent study limitations and biases.
S-CKD602 is a PEGylated liposomal formulation of CKD-602, a potent topoisomerase I inhibitor. The objective of this study was to characterize the bidirectional pharmacokinetic–pharmacodynamic (PK–PD) interaction between S-CKD602 and monocytes. Plasma concentrations of encapsulated CKD-602 and monocytes counts from 45 patients with solid tumors were collected following intravenous administration of S-CKD602 in the phase I study. The PK–PD models were developed and fit simultaneously to the PK–PD data, using NONMEM®. The monocytopenia after administration of S-CKD602 was described by direct toxicity to monocytes in a mechanism-based model, and by direct toxicity to progenitor cells in bone marrow in a myelosuppression-based model. The nonlinear PK disposition of S-CKD602 was described by linear degradation and irreversible binding to monocytes in the mechanism-based model, and Michaelis–Menten kinetics in the myelosuppression-based model. The mechanism-based PK–PD model characterized the nonlinear PK disposition, and the bidirectional PK–PD interaction between S-CKD602 and monocytes.
population pharmacokinetics; pharmacodynamics; PEGylated liposome; nonlinear kinetics
S-CKD602 is a pegylated liposomal formulation of CKD-602, a semi-synthetic camptothecin analogue. Pegylated (STEALTH®) liposomes can achieve extended drug exposure in plasma and tumor. Based on promising preclinical data, the first phase I study of S-CKD602 was performed in patients (pts) with refractory solid tumors.
S-CKD602 was administered IV every 3 weeks. Modified Fibonacci escalation was used (3–6 pts/cohort), and dose levels ranged from 0.1 to 2.5 mg/m2. Serial plasma samples were obtained over two weeks and total (lactone + hydroxyl acid) concentrations of encapsulated, released, and sum total (encapsulated + released) CKD602 measured by LC-MS/MS.
45 pts (21 male) were treated: median age 62 years (range: 33–79 years); ECOG status: 0 to 1 (43 pts) and 2 (2 pts). Dose-limiting toxicities of grade 3 mucositis occurred in 1/6 pts at 0.3 mg/m2, grade 3/4 bone marrow suppression in 2/3 pts at 2.5 mg/m2, and grade 3 febrile neutropenia and anemia in 1/6 pts at 2.1 mg/m2. The maximum tolerated dose was 2.1 mg/m2. Partial responses occurred in 2 pts with refractory ovarian cancer (1.7 and 2.1 mg/m2). High inter-patient variability occurred in the pharmacokinetic disposition of encapsulated and released CKD-602.
S-CKD602 represents a promising new liposomal camptothecin analogue with manageable toxicity and promising antitumor activity. Phase II studies of S-CKD602 at 2.1 mg/m2 IV once every 3 weeks are planned. Prolonged plasma exposure over 1 to 2 wks is consistent with STEALTH® liposomes and provides extended exposure compared with single doses of non-liposomal camptothecins.
Few studies have examined methods of contraception, beyond oral contraceptives (OCs) and tubal ligation, in relation to ovarian cancer risk.
Nine hundred two cases with incident ovarian/peritoneal/tubal cancer were compared to 1800 population-based controls. Women self-reported all methods of contraception using life calendars.
Each of the contraceptive methods examined reduced the risk of ovarian cancer as compared to use of no artificial contraception. Comparing ever versus never use, after adjustment for potentially confounding factors and all other methods of contraception, the methods of contraception that emerged as protective were OCs (adj OR 0.75, 95% CI 0.61–0.93); tubal ligation (adj OR 0.63, 95% CI 0.51–0.77); intrauterine devices (IUDs) (adj OR 0.75, 95% CI 0.59–0.95); and vasectomy (adj OR 0.77, 95% CI 0.61–0.99). While for oral contraceptives and tubal ligation, the longer the duration of use, the greater the effect, for IUDs the pattern was reversed: significant protection occurred with short duration and progressively greater risk (albeit non-significant) was seen with longer duration of use.
In the largest case-control study to date, a range of effective methods of contraception reduced the risk for ovarian cancer. OCs and tubal ligation reduced ovarian cancer risk with lower odds ratios with longer duration of use, whereas IUDs reduced risk overall, having the greatest impact with short duration of use.
contraception; contraceptive methods; oral contraceptives; tubal ligation; IUDs; ovarian cancer
Epithelial ovarian cancer (EOC) is the deadliest gynecologic malignancy in the United States. Unfortunately, a validated protein biomarker-screening test to detect early stage disease from peripheral blood has not yet been developed. The present investigation assesses the ability to identify tumor relevant proteins from ovarian cancer proximal fluids, including tissue interstitial fluid (TIF) and corresponding ascites, from patients with papillary serous EOC and translates these findings to targeted blood-based immunoassays.
Paired TIF and ascites collected from four papillary serous EOC patients at the time of surgery underwent immunodepletion, resolution by 1D gel electrophoresis and in-gel digestion for analysis by liquid chromatography-tandem mass spectrometry, which resulted in an aggregate identification of 569 and 171 proteins from TIF and ascites, respectively. Of these, peroxiredoxin I (PRDX1) was selected for validation in serum by ELISA and demonstrated to be present and significantly elevated (p = 0.0188) in 20 EOC patients with a mean level of 26.0 ng/mL (±9.27 SEM) as compared to 4.19 ng/mL (±2.58 SEM) from 16 patients with normal/benign ovarian pathology.
We have utilized a workflow for harvesting EOC-relevant proximal biofluids, including TIF and ascites, for proteomic analysis. Among the differentially abundant proteins identified from these proximal fluids, PRDX1 was demonstrated to be present in serum and shown by ELISA to be elevated by nearly 6-fold in papillary serous EOC patients relative to normal/benign patients. Our findings demonstrate the facile ability to discover potential EOC-relevant proteins in proximal fluids and confirm their presence in peripheral blood serum. In addition, our finding of elevated levels of PRDX1 in the serum of EOC patients versus normal/benign patients warrants further evaluation as a tumor specific biomarker for EOC.
This short communication piece provides an overview of the Latin American Supercourse, a collection of public health lectures in Spanish targeting educators in Mexico, US, and Spanish speaking countries.
Internet; Prevention; Cancer; Education; Communications; Public health
Laparoscopic radical hysterectomy appears to be a feasible alternative to laparotomy for early stage cervical cancer with similar surgical outcomes and lessened morbidity.
Gynecologic oncologists have recently begun using laparoscopic techniques to treat early stage cervical cancer. We evaluated a single institution's experience of laparoscopic radical hysterectomy and staging compared with laparotomy.
A retrospective chart review identified stage IA2 and IB1 cervical cancer patients who underwent laparoscopic radical hysterectomy and pelvic lymph node dissection from July 2003 to April 2009. A 2:1 cohort of patients treated with laparotomy were matched by stage.
Nine laparoscopic patients (3 stage IA2, 6 stage IB1) with 18 matched controls (6 and 12) were identified. Demographics for each group were similar. None had positive margins or lymph nodes. An average of 11.2 vs.13.9 pelvic lymph nodes (P=0.237) were removed. Average operating time was 231.7 vs. 207.2 minutes (P=0.434), and average estimated blood loss was 161.1 vs. 394.4mL (P=0.059). Average length of stay was 2.9 vs. 5.5 days (P=0.012). No transfusions or operative complications were noted in the laparoscopic group vs. 3 each in the open group (P=0.194). No laparoscopic patients and 5 open patients had a postoperative wound infection (P=0.079). No recurrences were noted.
Laparoscopic radical hysterectomy is a feasible alternative to laparotomy for early stage cervical cancer. Similar surgical outcomes are achieved with significantly less morbidity.
Laparoscopic radical hysterectomy; Cervical cancer
Aberrant glycosylation is a well-described hallmark of cancer. In a previous ovarian cancer case control study that examined polymorphisms in 26 glycosylation-associated genes, we found strong statistical evidence (P = 0.00017) that women who inherited two copies of a single-nucleotide polymorphism in the UDP-N-acetylgalactosamine:polypeptide N-acetylgalactosaminyltransferase, GALNT1, had decreased ovarian cancer risk. The current study attempted to replicate this observation. The GALNT1 single-nucleotide polymorphism rs17647532 was genotyped in 6,965 cases and 8,377 controls from 14 studies forming the Ovarian Cancer Association Consortium. The fixed effects estimate per rs17647532 allele was null (odds ratio, 0.99; 95% confidence interval, 0.92–1.07). When a recessive model was fit, the results were unchanged. Test for hetero geneity of the odds ratios revealed consistency across the 14 replication sites but significant differences compared with the original study population (P = 0.03). This study underscores the need for replication of putative findings in genetic association studies.
With advances in surgical techniques and chemotherapeutic agents, mortality rates from epithelial ovarian cancer (EOC) have slightly decreased over the last 30 years. However, EOC still ranks as the most deadly gynecologic cancer with an overall 5-year survival rate of 45%. Prognosis is especially disappointing for women with platinum-resistant disease, where 80% of patients will fail to respond to available therapies. Emerging treatment strategies have sub-sequently focused on targets which are integral to tumor growth and metastasis. In this review, we will focus on those innovative agents currently under investigation in clinical trials.
platinum-resistant; ovarian cancer; targeted therapy; immunotherapy; angiogenesis; growth factors
Disparities in cervical cancer incidence and mortality rates exist among women of African ancestry (African-American, African-Caribbean and African). Persistent cervical infection with Human papillomavirus (HPV) is associated with cervical dysplasia and if untreated, could potentially progress to invasive cervical cancer. Very few studies have been conducted to examine the true prevalence of HPV infection in this population. Comparisons of cervical HPV infection and the type-specific distribution of HPV were performed between cancer-free Caribbean and US women.
The Caribbean population consisted of 212 women from Tobago and 99 women from Jamaica. The US population tested, consisted of 82 women from Pittsburgh. The majority of the US subjects was Caucasian, 74% (61/82) while 12% (10/82) and 13% (11/82) were African-American or other ethnic groups, respectively. The age-adjusted prevalence of any HPV infection among women from Tobago was 35%, while for Jamaica, it was 81% (p < 0.0001). The age-adjusted prevalence of HPV infection for Caribbean subjects was not statistically significantly different from the US (any HPV: 47% vs. 39%, p > 0.1; high-risk HPVs: 27% vs. 25%, p > 0.1); no difference was observed between US-Blacks and Jamaicans (any HPV: 92% vs. 81%, p > 0.1; high-risk HPV: 50% vs. 53%, p > 0.1). However, US-Whites had a lower age-adjusted prevalence of HPV infections compared to Jamaican subjects (any HPV: 29% vs. 81%, p < 0.0001; high-risk HPV: 20% vs. 53%, p < 0.001). Subjects from Jamaica, Tobago, and US-Blacks had a higher proportion of high-risk HPV infections (Tobago: 20%, Jamaica: 58%, US-Blacks: 40%) compared to US-Whites (15%). Similar observations were made for the presence of infections with multiple high-risk HPV types (Tobago: 12%, Jamaica: 43%, US-Blacks: 30%, US-Whites: 8%). Although we observed similar prevalence of HPV16 infections among Caribbean and US-White women, there was a distinct distribution of high-risk HPV types when comparisons were made between the ethnic groups.
The higher prevalence of cervical HPV infections and multiple high-risk infections in Caribbean and US-Black women may contribute to the high incidence and prevalence of cervical cancer in these populations. Evaluation of a larger sample size is currently ongoing to confirm the distinct distribution of HPV types between ethnic groups.
The United States (US) Food & Drug Administration (FDA) recently approved a human papillomavirus (HPV) vaccine with the purpose of reducing the risk of cervical cancers caused by HPV 16 and HPV 18. It is important that the general population be educated about HPV and the HPV vaccine in order to make the appropriate decision whether or not to vaccinate against this virus. Participants from the adult US general population of Pittsburgh, Pennsylvania, USA and Hampton, Virginia, USA (18+ years old) were surveyed to determine their knowledge about HPV and the HPV vaccine, and to evaluate their perception of the vaccine efficacy and safety.
We report herein preliminary data for 202 participants. Fifty-five percent (55%) of the study population was White, 45% Black, and 1% was from other ethnic groups or did not disclose their ethnicity. A large proportion of participants had heard of the human papillomavirus (overall population: 93.6%; Pittsburgh: 95%; Hampton: 90%). Participants of African descent were slightly less aware of HPV than Whites (Black 89% vs. Whites 97%, p > 0.1). Although the majority of participants knew that HPV caused cervical cancer (84%), Whites were more informed than Black participants (91% vs. 73%, p = 0.044). Eighty-seven percent (87%) of participants had heard of the HPV vaccine (Pittsburgh: 92% and Hampton: 74%, p = 0.029); a higher proportion of Whites were aware of the vaccine when compared with Blacks (93% vs. 76%, p = 0.031). However, only 18% of the population knew that the current FDA-approved vaccine protected against genital warts and most cervical cancer (20% of Blacks and 16% of Whites, p > 0.1).
These data suggest that although the general population might be aware of HPV and the HPV vaccine, knowledge of the benefits of the HPV vaccination may not be apparent. Knowledge of HPV and the HPV vaccine could result in a likely choice of HPV vaccination and would subsequently reduce the incidence of cervical cancer.
The purpose of this study was to evaluate the efficacy of HDR brachytherapy for primary or recurrent vaginal cancer.
Between the years 2000 to 2006, 18 patients with primary or recurrent vaginal cancer were treated with brachytherapy (HDRB). Six patients had primary vaginal cancer (stage II to IVA) while 12 were treated for isolated vaginal recurrence (primary cervix = 4, vulva = 1 and endometrium = 7). Five patients had previous pelvic radiation therapy. All except one patient received external beam radiation therapy to a median dose of 45 Gy (range 31.2–55.8 Gy). The HDRB was intracavitary using a vaginal cylinder in 5 patients and interstitial using a modified Syed-Nesblett template in 13 patients. The dose of interstitial brachytherapy was 18.75 Gy in 5 fractions delivered twice daily. The median follow-up was 18 months (range 6–66 months).
Complete response (CR) was achieved in all but one patient (94%). Of these 17 patients achieving a CR, 1 had local recurrence and 3 had systemic recurrence at a median time of 6 months (range 6–22 months). The 2-year actuarial local control and cause-specific survival for the entire group were 88% and 82.5%, respectively. In subset analysis, the crude local control was 100% for primary vaginal cancer, 100% for the group with recurrence without any prior radiation and 67% for group with recurrence and prior radiation therapy. Two patients had late grade 3 or higher morbidity (rectovaginal fistula in one patient and chronic vaginal ulcer resulting in bleeding in one patient). Both these patients had prior radiation therapy.
Our small series suggests that HDRB is efficacious for primary or recurrent vaginal cancer. Patients treated with primary disease and those with recurrent disease without prior irradiation have the greatest benefit from HDRB in this setting. The salvage rate for patients with prior radiation therapy is lower with a higher risk of significant complications. Additional patients and follow-up are ongoing to determine the long-term efficacy of this approach.
Measurement of immune components in mucosal secretions is important for the evaluation of local immunity at the mucosal surfaces. The Weck-Cel ophthalmic sponge provides a method for the collection of these secretions. The sponge absorbs a relatively large volume of material, therefore allowing for quantitation of multiple immune components. Additionally, it provides a method in which the same device may be used to collect specimens from different mucosal sites, such as the genital tract and oral cavity. This sampling technique has successfully been applied for collection and measurement of antibody in oral and genital tract secretions. The purpose of this work was to optimize the extraction of protein from the sponge matrix. Of particular interest was the recovery of cytokines from the sponge. Satisfactory recovery of the cytokines interleukin 1β (IL-1β), IL-2, IL-5, IL-12, IL-6, IL-8, IL-10, and granulocyte-macrophage colony-stimulating factor was obtained. However, IL-4 and gamma interferon recovery rates remained low. Using an alteration of the published extraction method, cytokine concentrations were measured in cervical secretions from women using oral contraceptives. The data revealed detectable concentrations of IL-6, IL-10, IL-8, and IL-12 on cycle days 9 and 20. The proposed technique provides an easy, practical, and consistent method for collection of nonconventional body fluids, such as cervicovaginal fluids and saliva, for the assay of immunoglobulins and several cytokines.
Collection of cervical secretions for local immunological assessment requires that the secretions be collected prior to the Pap smear to avoid contamination with blood. The objective of the present study was to determine whether gentle collection of cervical secretions prior to a Pap smear collection influences the quality of the Pap smear. A total of 266 women were recruited. Half of the participants were assigned to collection of cervical secretions prior to Pap smear collection with Weck-cel sponges. The remaining half had only the Pap smear collection performed. Pap smear slides were reviewed and evaluated for quality by the Bethesda System adequacy criteria without knowledge of randomization. The proportions of limited or inadequate slides in the two study groups were compared by using the Pearson chi-square test. No significant differences were observed between the two study groups when overall Pap smear quality was evaluated (P = 0.29). Comparison of the two study groups with respect to individual adequacy criteria, including presence of air drying artifact, presence of obscuring blood, absence of metaplastic or endocervical cells from the transformation zone, scant cellularity, and presence of obscuring inflammatory cells, also revealed no significant differences between the two study groups. Results from the present study suggest that the collection of cervical secretions with Weck-cel sponges does not adversely impact the quality of subsequently obtained Pap smears.
We investigated risk factors for Type II (n = 176) vs. Type I (n = 1,576) endometrial cancer (EC) in cases treated at Magee-Womens Hospital between 1996 and 2008.
Clinical data were available from the University of Pittsburgh Medical Center (UPMC) Network Cancer Registry. Logistic regression was used to estimate the adjusted odds of having Type II EC vs. Type I EC. Risk factors of interest in this analysis were age, race, body mass index (BMI), year of diagnosis, parity, menopausal status, and history of additional primary tumors.
Relative to women with Type I EC, women with Type II EC were more likely to be older at diagnosis (OR: 1.03 per 1 year increase in age, 95% CI 1.01–1.05), of non-white race (OR: 2.95, 95% CI 1.66–5.27), have a history of additional primary tumors (OR: 1.56, 95% CI 1.05–2.32), and less likely to be obese (OR: 0.45, 95% CI 0.29–0.70).
In this large retrospective cohort of patients with EC, the striking difference in risk factors associated with Type II vs. Type I tumors suggests that these subtypes represent different disease entities that require different treatment modalities. Currently, Type II cases have a significantly worse prognosis compared to Type I. Further characterization of risk factors associated with developing Type II tumors is needed to prevent this aggressive malignancy.
Endometrial cancer; Epidemiology; Type I; Type II
The Ovarian Cancer Association Consortium selected 7 candidate single nucleotide polymorphisms (SNPs), for which there is evidence from previous studies of an association with variation in ovarian cancer or breast cancer risks. The SNPs selected for analysis were F31I (rs2273535) in AURKA, N372H (rs144848) in BRCA2, rs2854344 in intron 17 of RB1, rs2811712 5′ flanking CDKN2A, rs523349 in the 3′ UTR of SRD5A2, D302H (rs1045485) in CASP8 and L10P (rs1982073) in TGFB1. Fourteen studies genotyped 4,624 invasive epithelial ovarian cancer cases and 8,113 controls of white non-Hispanic origin. A marginally significant association was found for RB1 when all studies were included [ordinal odds ratio (OR) 0.88 (95% confidence interval (CI) 0.79-1.00) p = 0.041 and dominant OR 0.87 (95% CI 0.76-0.98) p = 0.025]; when the studies that originally suggested an association were excluded, the result was suggestive although no longer statistically significant (ordinal OR 0.92, 95% CI 0.79-1.06). This SNP has also been shown to have an association with decreased risk in breast cancer. There was a suggestion of an association for AURKA, when one study that caused significant study heterogeneity was excluded [ordinal OR 1.10 (95% CI 1.01-1.20) p = 0.027; dominant OR 1.12 (95% CI 1.01-1.24) p = 0.03]. The other 5 SNPs in BRCA2, CDKN2A, SRD5A2, CASP8 and TGFB1 showed no association with ovarian cancer risk; given the large sample size, these results can also be considered to be informative. These null results for SNPs identified from relatively large initial studies shows the importance of replicating associations by a consortium approach.
association study; neoplasms; ovarian cancer; replication; single nucleotide polymorphism