Aspirin and epithelial ovarian cancer

Aspirin inhibits platelets from reprogramming breast tumor cells and promoting metastasis

It is now recognized that compounds released from tumor cells can activate platelets, causing the release of platelet-derived factors into the tumor microenvironment. Several of these factors have been shown to directly promote neovascularization and metastasis, yet how the feedback between platelet releasate and the tumor cell affects metastatic phenotype remains largely unstudied. Here, we identify that breast tumor cells secrete high levels of interleukin 8 (IL-8, CXCL8) in response to platelet releasate, which promotes their invasive capacity. Furthermore, we found that platelets activate the Akt pathway in breast tumor cells, and inhibition of this pathway eliminated IL-8 production. We therefore hypothesized inhibiting platelets with aspirin could reverse the prometastatic effects of platelets on tumor cell signaling. Platelets treated with aspirin did not activate the Akt pathway, resulting in reduced IL-8 secretion and impaired tumor cell invasion. Of note, patients with breast cancer receiving aspirin had lower circulating IL-8, and their platelets did not increase tumor cell invasion compared with patients not receiving aspirin. Our data suggest platelets support breast tumor metastasis by inducing tumor cells to secrete IL-8. Our data further support that aspirin acts as an anticancer agent by disrupting the communication between platelets and breast tumor cells.

The role of aspirin in the prevention of ovarian, endometrial and cervical cancers

Drug repurposing is the application of an existing licenced drug for a new indication and potentially provides a faster and cheaper approach to developing new anti-cancer agents. Gynaecological cancers contribute significantly to the global cancer burden, highlighting the need for low cost, widely accessible therapies. A large body of evidence supports the role of aspirin as an anti-cancer agent, and a number of randomized trials are currently underway aiming to assess the potential benefit of aspirin in the treatment of cancer. This review summarizes the evidence underpinning aspirin use for the prevention of the development and recurrence of gynaecological cancers (ovarian, endometrial and cervical) and potential mechanisms of action.

Aspirin suppresses tumor cell-induced angiogenesis and their incongruity

Tumor neovascularization/tumor angiogenesis is a pathophysiological process in which new blood vessels are formed from existing blood vessels in the primary tumors to supply adequate oxygen and nutrition to cancer cells for their proliferation and metastatic growth to the distant organs. Therefore, controlling tumor angiogenesis is an attractive target for cancer therapy. Structural abnormalities of the vasculature (i.e., leakiness due to the abnormal lining of pericytes on the microvessels) are one of the critical features of tumor angiogenesis that sensitizes vascular cells to cytokines and helps circulating tumor cells to metastasize to distant organs. Our goal is to repurpose the drugs that may prevent tumor angiogenesis or normalize the vessels by repairing leakiness via recruiting pericytes or both. In this study, we tested whether aspirin (ASA), which could block primary tumor growth, regulates tumor angiogenesis. We investigated the effects of low (1 mM) and high (2.5 mM) doses of ASA (direct effect), and ASA-treated or untreated triple negative breast cancer (TNBC) cells' conditioned media (indirect effect) on endothelial cell physiology. These include in vitro migration using modified Boyden chamber assay, in vitro capillary-like structure formation on Matrigel, interactions of pericytes-endothelial cells and cell permeability using in vitro endothelial permeability assay. We also examined the effect of ASA on various molecular factors associated with tumor angiogenesis. Finally, we found the outcome of ASA treatment on in vivo tumor angiogenesis. We found that ASA-treatment (direct or indirect) significantly blocks in vitro migration and capillary-like structure formation by endothelial cells. Besides, we found that ASA recruits pericytes from multipotent stem cells and helps in binding with endothelial cells, which is a hallmark of normalization of blood vessels, and decreases in vitro permeability through endothelial cell layer. The antiangiogenic effect of ASA was also documented in vivo assays. Mechanistically, ASA treatment blocks several angiogenic factors that are associated with tumor angiogenesis, and suggesting ASA blocks paracrine-autocrine signaling network between tumor cells and endothelial cells. Collectively, these studies implicate aspirin with proper dose may provide potential therapeutic for breast cancer via blocking as well as normalizing tumor angiogenesis.

Associations between aspirin use and the risk of cancers: a meta-analysis of observational studies

Background

Epidemiological studies have clarified the potential associations between regular aspirin use and cancers. However, it remains controversial on whether aspirin use decreases the risk of cancers risks. Therefore, we conducted an updated meta-analysis to assess the associations between aspirin use and cancers.

Methods

The PubMed, Embase, and Web of Science databases were systematically searched up to March 2017 to identify relevant studies. Relative risks (RRs) with 95% confidence intervals (CIs) were used to assess the strength of associations.

Results

A total of 218 studies with 309 reports were eligible for this meta-analysis. Aspirin use was associated with a significant decrease in the risk of overall cancer (RR = 0.89, 95% CI: 0.87–0.91), and gastric (RR = 0.75, 95% CI: 0.65–0.86), esophageal (RR = 0.75, 95% CI: 0.62–0.89), colorectal (RR = 0.79, 95% CI: 0.74–0.85), pancreatic (RR = 0.80, 95% CI: 0.68–0.93), ovarian (RR = 0.89, 95% CI: 0.83–0.95), endometrial (RR = 0.92, 95% CI: 0.85–0.99), breast (RR = 0.92, 95% CI: 0.88–0.96), and prostate (RR = 0.94, 95% CI: 0.90–0.99) cancers, as well as small intestine neuroendocrine tumors (RR = 0.17, 95% CI: 0.05–0.58).

Conclusions

These findings suggest that aspirin use is associated with a reduced risk of gastric, esophageal, colorectal, pancreatic, ovarian, endometrial, breast, and prostate cancers, and small intestine neuroendocrine tumors.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4156-5) contains supplementary material, which is available to authorized users.

Increased Plasma Levels of Pentraxin 3 Are Associated with Poor Prognosis of Colorectal Carcinoma Patients

Colorectal carcinoma (CRC) is one of the most common cancers globally. It is essential to identify a prognostic predictor for CRC. Pentraxin 3 (PTX3) is a glycoprotein that is secreted by a variety of human cells. It plays an important role in inflammation and immune regulation. Increasing evidence reveals that elevated PTX3 expression is related to poor prognosis in various cancers. The aim of the study was to determine the usefulness of plasma PTX3 level as a prognostic predictor in CRC. Total 184 CRC patients and 216 controls were included. Plasma levels of PTX3 were determined using Enzyme-linked immunosorbent assays. On admission, plasma PTX3 levels in CRC patients were higher than those in controls (11.8 ± 2.5 ng/ml vs. 3.1 ± 0.9 ng/ml, P < 0.001). After resection, plasma PTX3 levels in patients were decreased (6.0 ± 1.4 ng/ml, P = 0.007), and were elevated at the time of relapse (10.8 ± 2.8 ng/ml, P < 0.001). During the 60-month follow-up period, 108 patients suffered from relapse. Plasma PTX3 levels of ≥ 12 ng/ml on admission were associated with relapse (OR: 3.11, 95% CI: 1.74 ~ 6.29), and tumor-free survival rate in those patients with plasma PTX3 levels of ≥ 12 ng/ml was lower than that in other patients (P = 0.001). Furthermore, plasma PTX3 levels on admission showed positive linear correlations with plasma complement 3, 4 and 5b9 levels (P < 0.001, P < 0.001, P < 0.001). Therefore, we propose that PTX3 is an independent prognostic indicator in CRC.

Analgesic medication use and risk of epithelial ovarian cancer in African American women

BACKGROUND

Existing literature examining analgesic medication use and epithelial ovarian cancer (EOC) risk has been inconsistent, with the majority of studies reporting an inverse association. Race-specific effects of this relationship have not been adequately addressed.

METHODS

Utilising data from the largest population-based case-control study of EOC in African Americans, the African American Cancer Epidemiology Study, the relationship between analgesic use (aspirin, non-aspirin nonsteroidal anti-inflammatory drugs (NSAIDs), and acetaminophen) and risk of EOC was estimated by multivariate logistic regression. The association of frequency, duration, and indication of analgesic use on EOC risk was also assessed.

RESULTS

Aspirin use, overall, was associated with a 44% lower EOC risk (OR=0.56; 95% CI=0.35-0.92) and a 26% lower EOC risk was observed for non-aspirin NSAID use (OR=0.74; 95% CI=0.52-1.05). The inverse association was strongest for women taking aspirin to prevent cardiovascular disease and women taking non-aspirin NSAIDs for arthritis. Significantly decreased EOC risks were observed for low-dose aspirin use, daily aspirin use, aspirin use for <5 years, and occasional non-aspirin NSAID use for a duration of ⩾5 years. No association was observed for acetaminophen use.

CONCLUSIONS

Collectively, these findings support previous evidence that any NSAID use is inversely associated with EOC risk.

Aspirin, nonaspirin nonsteroidal anti-inflammatory drug, and acetaminophen use and risk of invasive epithelial ovarian cancer: a pooled analysis in the Ovarian Cancer Association Consortium

BACKGROUND

Regular aspirin use is associated with reduced risk of several malignancies. Epidemiologic studies analyzing aspirin, nonaspirin nonsteroidal anti-inflammatory drug (NSAID), and acetaminophen use and ovarian cancer risk have been inconclusive.

METHODS

We analyzed pooled data from 12 population-based case-control studies of ovarian cancer, including 7776 case patients and 11843 control subjects accrued between 1992 and 2007. Odds ratios (ORs) for associations of medication use with invasive epithelial ovarian cancer were estimated in individual studies using logistic regression and combined using random effects meta-analysis. Associations between frequency, dose, and duration of analgesic use and risk of ovarian cancer were also assessed. All statistical tests were two-sided.

RESULTS

Aspirin use was associated with a reduced risk of ovarian cancer (OR = 0.91; 95% confidence interval [CI] = 0.84 to 0.99). Results were similar but not statistically significant for nonaspirin NSAIDs, and there was no association with acetaminophen. In seven studies with frequency data, the reduced risk was strongest among daily aspirin users (OR = 0.80; 95% CI = 0.67 to 0.96). In three studies with dose information, the reduced risk was strongest among users of low dose (<100 mg) aspirin (OR = 0.66; 95% CI = 0.53 to 0.83), whereas for nonaspirin NSAIDs, the reduced risk was strongest for high dose (≥500 mg) usage (OR = 0.76; 95% CI = 0.64 to 0.91).

CONCLUSIONS

Aspirin use was associated with a reduced risk of ovarian cancer, especially among daily users of low-dose aspirin. These findings suggest that the same aspirin regimen proven to protect against cardiovascular events and several cancers could reduce the risk of ovarian cancer 20% to 34% depending on frequency and dose of use.

Meta-analysis on the association between non-steroidal anti-inflammatory drug use and ovarian cancer

AIM

Animal and in vitro studies suggest that the use of non-steroidal anti-inflammatory drugs (NSAIDs) may be associated with reduced risk for ovarian cancer. However, results from these studies have been inconsistent. The aim of our study was to review and summarize the evidence provided by longitudinal studies on the association between NSAID use and ovarian cancer risk.

METHODS

A comprehensive literature search for articles published up to December 2011 was performed. Prior to performing a meta-analysis, the studies were evaluated for publication bias and heterogeneity. Relative risk (RR) or odds ratios (OR) were calculated.

RESULTS

Seventeen reports (13 case-control studies, one clinical trial and three cohort studies), published between 1998 and 2011 were identified. There was no evidence of an association between aspirin use and ovarian cancer risk based on a random-effects model (RR = 0.91, 95% confidence interval (CI) 0.82, 1.01) or a fixed-effects model (RR = 0.94, 95% CI 0.87, 1.01). Similarly, we did not find strong evidence of an association between non-aspirin NSAID use and ovarian cancer using a random-effects model (RR = 0.89, 95% CI 0.74, 1.08) or a fixed-effects model (RR = 0.86, 95% CI 0.76, 0.98). Furthermore, our analysis did not show a strong association between frequency or duration of non-aspirin-NSAID use and ovarian cancer.

CONCLUSIONS

Our findings indicate that there is no strong evidence of an association between aspirin/NA-NSAID use and ovarian cancer. However, this subject deserves further investigation.

Nonsteroidal anti-inflammatory drugs and risk of ovarian cancer: systematic review and meta-analysis of observational studies

OBJECTIVE

Several observational studies have investigated the association between nonsteroidal anti-inflammatory drug (NSAID) use and ovarian cancer risk, but with conflicting results. We performed a systematic review and meta-analysis of the association between NSAID use and ovarian cancer risk.

DESIGN

Systematic review and meta-analysis of observational studies published until September 2012.

SETTING

Studies were identified from the PubMed database.

POPULATION

Fourteen case-control and seven cohort studies were included.

METHODS

Pooled relative risks (RRs) with corresponding 95% confidence intervals (CI) for aspirin and non-aspirin NSAIDs, separately, were calculated. Both fixed and random effect models were applied, but only random effect pooled RRs are presented. Risk estimates for invasive and borderline ovarian tumors combined and for invasive ovarian tumors only were calculated. Furthermore, heterogeneity and publication bias were evaluated.

MAIN OUTCOME MEASURES

Ovarian cancer.

RESULTS

In the combined analysis, a slight inverse association between use of aspirin (RR 0.93; 95% CI 0.84-1.02) and non-aspirin NSAIDs (RR 0.94; 95% CI 0.84-1.06) and ovarian cancer risk was found, although it was not statistically significant. However, the risk of invasive ovarian cancer was significantly reduced with use of aspirin (RR 0.88; 95% CI 0.79-0.98). A similar tendency was observed for non-aspirin NSAIDs, but the results were not significant.

CONCLUSIONS

This meta-analysis showed a slight inverse association between NSAIDs and risk of ovarian cancer. However, data suggest that a chemopreventive effect of NSAIDs may be restricted to invasive ovarian tumors. Further research on NSAIDs and ovarian cancer is needed before definite conclusions can be drawn.

Use of analgesic drugs and risk of ovarian cancer: results from a Danish case-control study

OBJECTIVE

The role of analgesic drug use in development of ovarian cancer is not fully understood. We examined the association between analgesic use and risk of ovarian cancer. In addition, we examined whether the association differed according to histological types.

DESIGN

Population-based case-control study.

SETTING

Denmark in the period 1995-1999.

POPULATION

We included 756 women with epithelial ovarian cancer and 1564 randomly selected control women aged 35-79 years.

METHODS

Information on analgesic drug use was collected from personal interviews. Analgesic drugs were divided into the following categories: any analgesics; aspirin; non-aspirin non-steroidal anti-inflammatory drugs; paracetamol; and other analgesic drugs. The association between analgesic drug use and ovarian cancer risk was analysed using multiple logistic regression models. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated.

MAIN OUTCOME MEASURES

Epithelial ovarian cancer.

RESULTS

Women with a regular use of any analgesics (OR = 0.79; 95% CI 0.62 - 1.01) or aspirin (OR = 0.68; 95% CI 0.46 - 1.02) had a decreased risk of ovarian cancer, although not statistically significant. Regular use of non-aspirin non-steroidal anti-inflammatory drugs, paracetamol or other analgesics did not decrease ovarian cancer risk. Use of any analgesics (OR = 0.72; 95% CI 0.53-0.98) or aspirin (OR = 0.60; 95% CI 0.36-1.00) resulted in a statistically significant decreased risk of serous ovarian cancer but not mucinous or other ovarian tumors.

CONCLUSION

In accordance with most previous studies, our results indicate a possible inverse association between analgesic use, particularly aspirin, and ovarian cancer risk.

Non-steroidal anti-inflammatory drug use and ovarian cancer risk: findings from the NIH-AARP Diet and Health Study and systematic review

BACKGROUND

Chronic inflammation has been proposed as a risk factor for ovarian cancer. Some data suggest that anti-inflammatory medications may be protective against ovarian cancer; however, results have been inconsistent.

METHODS

We evaluated the risk of epithelial ovarian cancer with regular use of NSAIDs prospectively in the NIH-AARP Diet and Health Study, using Cox proportional hazard models. We also examined the risk of common subtypes of epithelial ovarian cancer (serous, mucinous, endometrioid, clear cell, and other epithelial) with regular use of NSAIDs. In addition, we performed meta-analyses summarizing the risk of ovarian cancer with "regular use" of NSAIDs in previously published studies.

RESULTS

We did not observe a significant association between regular use of NSAIDs with ovarian cancer risk in the AARP cohort (aspirin: RR 1.06, 95 % CI 0.87-1.29; non-aspirin NSAIDs: RR 0.93, 95 % CI 0.74-1.15); however, summary estimates from prospective cohort studies demonstrated that use of non-aspirin NSAIDs may reduce the risk of ovarian cancer (RR 0.88, 95 % CI 0.77-1.01). Although not significant, we found that mucinous tumors were inversely associated with non-aspirin NSAID use (RR 0.69, 95 % CI 0.23-2.10) in the AARP cohort, which was supported by the meta-analysis (RR 0.69, CI 0.50-0.94.)

CONCLUSION

Although results from the NIH-AARP cohort study were not statistically significant, our meta-analysis suggests that non-aspirin NSAIDs may be protective against ovarian cancer. Additional analyses, focusing on dose, duration, and frequency of NSAID use and accounting for ovarian cancer heterogeneity are necessary to further elucidate the association between NSAID use and ovarian cancer risk.

Migraine history, nonsteroidal anti-inflammatory drug use, and risk of postmenopausal endometrial cancer

Endometrial cancer is primarily a hormonally mediated disease. As such, factors that mediate or reflect exposure to estrogens, or that mediate response to such exposure, may plausibly be associated with endometrial cancer risk. History of migraines, another hormonally mediated condition, has recently been associated with a reduced risk of hormone receptor-positive breast cancer; however, the relationship between migraines and endometrial cancer has not previously been explored. We evaluated the relationship between migraine history and endometrial cancer risk in postmenopausal women, considering also the potential impact of nonsteroidal anti-inflammatory drug (NSAID) use, given the relationship of NSAIDs to hormones and to migraine history. We identified 93,384 women participating in the Women's Health Initiative prospective cohort who had an intact uterus at the time of study entry. Using Cox proportional hazards regression, we assessed risk of endometrial cancer during study follow-up according to history of migraines and according to current NSAID use at the time of study entry, adjusting for age, study arm, race, and hormone therapy use. We also evaluated interaction in these associations by body mass index. Having a history of migraines was not associated with endometrial cancer risk [hazard ratio (HR) = 0.91, 95% confidence interval (CI) = 0.75-1.11], regardless of body mass index (BMI) or NSAID use status. Similarly, current NSAID use was not associated with endometrial cancer risk (HR = 1.01, 95% CI = 0.88-1.16), regardless of BMI. Migraine history and NSAID use do not appear to be associated with risk of endometrial cancer.

Use of nonsteroidal anti-inflammatory drugs and risk of ovarian and endometrial cancer: the Multiethnic Cohort

BACKGROUND

Chronic inflammation may play an etiologic role in ovarian and endometrial cancer, and it is hypothesized that nonsteroidal anti-inflammatory drugs (NSAID) decrease the risk of developing these malignancies. No prospective study with a large multiethnic population has explored this hypothesis.

METHODS

We investigated whether NSAID use was associated with risks of ovarian and endometrial cancer in the Multiethnic Cohort Study. Medication use of at least twice a week for ≥1 month was assessed at baseline. Multivariable relative risks (RR) and 95% confidence intervals (CI) were estimated using Cox proportional hazards models.

RESULTS

During 13.3 years of follow-up, 275 ovarian and 620 endometrial incident cases were identified among approximately 64,000 women included in this analysis (16.5% African Americans, 30.8% Japanese, 7.7% Native Hawaiians, 18.9%, Latinas, and 26.0% whites). The RR (95% CI) for ovarian cancer associated with aspirin, non-aspirin NSAIDs, and acetaminophen were 0.87 (0.68-1.14), 0.97 (0.74-1.26), and 0.86 (0.67-1.12), respectively. The RR (95% CI) for endometrial cancer associated with aspirin, non-aspirin NSAIDs, and acetaminophen were 0.93 (0.79-1.10), 0.88 (0.74-1.05), and 0.96 (0.81-1.13), respectively. No heterogeneity across ethnic groups (P ≥ 0.29) or dose-response relation with increased duration of use (P(trend) ≥ 0.16) was observed. The results did not differ by tumor histology.

CONCLUSIONS

We found no compelling evidence to support an association between the use of NSAIDs and risk of ovarian and endometrial cancers in a multiethnic population.

IMPACT

It is unlikely that NSAID is involved in the etiology of endometrial and ovarian cancer.

Nonsteroidal antiinflammatory drugs and progestins synergistically enhance cell death in ovarian epithelial cells

OBJECTIVE

There is growing evidence that progestins and nonsteroidal antiinflammatory drugs (NSAIDs) may prevent ovarian cancer. Because both induce apoptosis, we investigated the potential for synergistic impact of combined drug treatment on cell death.

STUDY DESIGN

Using normal and malignant human ovarian epithelial cells and an NSAID-sensitive human colon cancer cell line, we evaluated the effects of progestins and NSAIDs alone and in combination on apoptosis.

RESULTS

Both progestins and NSAIDs dose dependently inhibited cell growth (P < .0001). Doses of NSAIDs or progestins that independently reduced cell viability by less than 30% synergistically reduced cell viability by 70-95% when combined. Similarly, the NSAID/progestin combination conferred 4- to 18-fold (P < .05) increased apoptosis over either treatment alone.

CONCLUSION

Our results suggest it may be possible to combine progestins and NSAIDs to achieve ovarian cancer prevention at lower doses of each than are required for single administration, thereby lessening the risk of side effects posed by these agents.

Synergistic cytotoxic effect of sulindac and pyrrolidine dithiocarbamate against ovarian cancer cells

Sulindac, a non-steroidal anti-inflammatory drug, suppresses carcinogenesis and inhibits growth of tumor cells. Pyrrolidine dithiocarbamate (PDTC), a potent NF-κB inhibitor, has been also identified as a potential anti-neoplastic agent. We hypothesized that combination of sulindac and PDTC could result in augmentation of cytotoxicity against ovarian cancer cells. The effect of sulindac and PDTC was examined on several ovarian cancer lines. Tumor cell viability was assessed using the MTT assay. Annexin-V/PI staining was used to detect apoptosis, cell cycle distribution was analyzed in FACS, and expression of cellular proteins was detected by Western blotting. Incubation of OVA-14, OVP-10 and CAOV-1 ovarian cancer cells with sulindac and PDTC resulted in significantly greater inhibition of cell viability compared to either compound alone. In a model of OVA-14 cells it was evident that this effect was not related to the expression of COX enzymes since both active (sulindac sulfide) and inactive (sulindac) in vitro compounds affected the growth of tumor cells to a similar extent and synergized in cytotoxicity with PDTC. Combination of sulindac and PDTC lead to G0 arrest and massive apoptosis in co-treated cultures. Western blotting analysis argued for induction of the mitochondrial apoptotic pathway. These data demonstrate the synergistic cytotoxic effect of sulindac and PDTC on ovarian cancer cells through apoptosis and cell cycle arrest and prompt to test the efficacy of this combination in animal models.

Nonsteroidal anti-inflammatory drugs and esophageal inflammation - Barrett's esophagus - adenocarcinoma sequence: a meta-analysis

The incidence of esophageal adenocarcinoma has markedly increased in the last few decades and Barrett's esophagus is regarded as the precursor lesion of this cancer. The aim of the study was to quantify the adenocarcinoma risk associated with nonsteroidal anti-inflammatory drug use and to determine at which stage chemoprevention with this drug is the most effective in esophageal inflammation - Barrett's esophagus - adenocarcinoma sequence. A literature search was performed to identify studies published between 1998 and 2009 for relevant risk estimates. Fixed and random effect meta-analytical techniques were conducted for aspirin, nonaspirin nonsteroidal anti-inflammatory drugs, and all nonsteroidal anti-inflammatory drugs. Four cohort and 10 case-control studies were included. Use of aspirin and nonaspirin nonsteroidal anti-inflammatory drugs in normal population was associated with a reduced risk of adenocarcinoma (odds ratio [OR]: 0.73, 95% confidence interval [CI]: 0.65-0.83; OR: 0.84, 95% CI: 0.72-0.98, respectively). The use of all nonsteroidal anti-inflammatory drugs was associated with a reduced risk of adenocarcinoma (relative risk [RR]: 0.64, 95% CI: 0.42-0.96) in Barrett's esophagus patients. However, no obvious dose-effect relationships were found. In addition, we discovered a reverse association between drugs use and adenocarcinoma risk in people without a history of upper gastrointestinal tract disorders (OR: 0.57, 95% CI: 0.43-0.77, P= 0.12). Our meta-analyses suggest a protective effect of nonsteroidal anti-inflammatory drugs on the risk of adenocarcinoma. Our results also suggest that the drugs might act after the formation of Barrett's epithelium in the esophageal inflammation - Barrett's esophagus - adenocarcinoma sequence.

Polycystic Ovary Syndrome: Update on Treatment Options and Treatment Considerations for the Future

Polycystic ovary syndrome is an endocrine disorder characterized by insulin resistance, hyperandrogenemia, obesity, and inflammation, and is the most common cause of infertility. Women with PCOS are at higher risk than non-PCOS women for diabetes, cardiovascular disease, endometrial cancer, and psychiatric disorders. Because many abnormalities present in PCOS and symptoms vary considerably among PCOS women, treatment is guided by presentation and does not consist of simply one modality. Often, however, one type of medication can ameliorate more than one abnormality in PCOS. This review summarizes current research on several treatment modalities for PCOS, including drugs that are fairly well-established as efficacious and other agents that may prove efficacious in the future, with particular emphasis on the benefits and barriers of lifestyle change.

Pooled analysis of the association of PTGS2 rs5275 polymorphism and NSAID use with invasive ovarian carcinoma risk

Inflammation is postulated to play an important role in ovarian carcinogenesis. Prostaglandin endoperoxide synthase 2 (PTGS2) is responsible for the conversion of arachidonic acid to prostaglandins in response to inflammation. In a pooled analysis of two population-based studies, the Hawaii Ovarian Cancer Case-Control Study and the New England Case-Control Study, including 1,025 women with invasive ovarian carcinoma and 1,687 cancer-free controls, the association of ovarian cancer risk with the PTGS2 rs5275 polymorphism and the use of nonsteroidal antiinflammatory drugs (NSAIDs) were examined. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression. In the pooled analysis, the CC genotype was associated with a reduced risk of nonserous ovarian carcinoma (OR = 0.66; CI: 0.44-0.98). In addition, the lowest risk was observed among carriers of the CC genotype who were users of only nonaspirin NSAIDs (OR = 0.43; CI:0.20-0.93) in all women combined. The association of PTGS2 rs5275 with nonserous ovarian carcinoma and possible effect modification by NSAID use needs further validation, preferably in prospective studies.

Nonsteroidal anti-inflammatory drugs and risk for ovarian and endometrial cancers in the Iowa Women's Health Study

BACKGROUND

Several epidemiologic studies have shown inverse associations between use of nonsteroidal anti-inflammatory drugs (NSAID) and incident ovarian cancer, but the results are inconsistent. There have been only a few studies examining possible links between NSAIDs and endometrial cancer risk. We investigated associations between use of NSAIDs and incident ovarian and endometrial cancers in a prospective cohort of about 20,000 women with ages from 58 to 76 years in 1992. Participants were asked how often they used aspirin and nonaspirin NSAIDs. Over 15 years, 311 endometrial and 167 ovarian incident malignancies were identified. Multivariate-adjusted hazard ratios were estimated using Cox proportional regression.

RESULTS

Compared with women who reported no use of aspirin, the relative risks for ovarian cancer for those who used aspirin <2, 2 to 5 times, and > or = 6 times per week were 0.83, 0.77, and 0.61, respectively (P trend = 0.04). We did not observe any association between nonaspirin NSAIDs use and ovarian cancer risk. Neither did we find associations between aspirin or nonaspirin NSAIDs use and risk for endometrial cancer.

CONCLUSIONS

Our results suggest a possible inverse association between frequency of aspirin use and risk for ovarian cancer.

Epidemiological and genetic factors associated with ovarian cancer

The purpose of this article was to provide a comprehensive review of the epidemiological and genetic factors associated with ovarian cancer. A more complete understanding of the determinants of ovarian cancer may lead to the development of better screening and detection methods for this disease. The first section of this article reviews current literature on screening and early detection of ovarian cancer. The second section reviews the epidemiology of ovarian cancer, specifically highlighting the risk factors associated with the development of this disease. The article concludes with a discussion of how oncology nurses can apply this information to improve patient care.

Use of nonsteroidal antiinflammatory agents and incidence of ovarian cancer in 2 large prospective cohorts

Epidemiologic data on the association between nonsteroidal antiinflammatory drugs (NSAIDs) and ovarian cancer risk have been inconsistent. The authors prospectively examined the association between regular use of aspirin and nonaspirin NSAIDs and ovarian cancer incidence among 197,486 participants of the Nurses' Health Study (NHS) and the Nurses' Health Study-II (NHS-II) over 24 and 16 years of follow-up, respectively. Information on aspirin was initially assessed in 1980 (NHS) and 1989 (NHS-II) and on nonaspirin NSAIDs and acetaminophen in 1990 (NHS) and 1989 (NHS-II) and updated throughout follow-up. The authors used Cox proportional hazards models adjusting for ovarian cancer risk factors. A total of 666 confirmed cases of epithelial ovarian cancer were identified over 2,790,986 person-years of follow-up. The hazard ratios associated with regular use of aspirin, nonaspirin NSAIDs, and acetaminophen were 1.11 (95% confidence interval (CI): 0.92, 1.33), 0.81 (95% CI: 0.64, 1.01), and 1.14 (95% CI: 0.92, 1.43), respectively. The authors did not observe a dose-response relation with increased frequency or duration of regular use of any of these medications and ovarian cancer incidence. The results did not differ substantially by tumor histology. In this large prospective study, the authors found no compelling evidence to support an association between regular use of aspirin, nonaspirin NSAIDs, or acetaminophen and ovarian cancer incidence.

Markers of inflammation and risk of ovarian cancer in Los Angeles County

Factors that increase inflammation have been suggested to influence the development of ovarian cancer, but these factors have not been well studied. To further investigate this question, we studied the role of talc use, history of endometrioisis and use of non-steroidal anti-inflammatory drugs (NSAIDs) and risk of ovarian cancer in a population-based case-control study in Los Angeles County involving 609 women with newly diagnosed epithelial ovarian cancer and 688 population-based control women. Risk of ovarian cancer increased significantly with increasing frequency and duration of talc use; compared to never users risk was highest among long-duration (20+ years), frequent (at least daily) talc users (adjusted relative risk (RR) = 2.08, 95% confidence interval (CI) = 1.34-3.23). A history of physician-diagnosed endometriosis was statistically significantly associated with risk (RR = 1.66, 95% CI = 1.01-2.75). Women who were talc users and had a history of endometriosis showed a 3-fold increased risk (RR = 3.12, 95% CI = 1.36-7.22). Contrary to the hypothesis that risk of ovarian cancer may be reduced by use of NSAIDs; risk increased with increasing frequency (per 7 times/week, RR = 1.27, 95% CI = 1.14-1.43) and years of NSAID use (per 5 years of use, RR = 1.25, 95% CI = 1.10-1.42); this was consistent across types of NSAIDs. We conclude that risk of ovarian cancer is significantly associated with talc use and with a history of endometriosis, as has been found in previous studies. The NSAID finding was unexpected and suggests that factors associated with inflammation are associated with ovarian cancer risk. This result needs confirmation with careful attention to the reasons for NSAID use.

Effects of a selective cyclooxygenase-1 inhibitor in SKOV-3 ovarian carcinoma xenograft-bearing mice

To evaluate the effect of a cyclooxygenase-1 (COX-1) inhibitor, SC-560, on the growth inhibition of s.c. human ovarian SKOV-3 carcinoma and on angiogenesis. Human ovarian SKOV-3 carcinoma cells xenograft-bearing mice were treated with SC-560, a COX-1-selective inhibitor, 6 mg/kg alone i.g. daily, and i.p. injections of cisplatin 3 mg/kg every other day for 21 days. Prostaglandin E(2) (PGE(2)) levels were determined by ELISA. Microvessel density (MVD) of ovarian carcinoma was determined with anti-CD(34) as the label by immunohistochemistry. In addition, the expression of COX-1 at protein levels in the control group was detected by immunohistochemistry. SC-560 reduced the growth of tumors when SKOV-3 cells were xenografted in nude female mice. The inhibitory rates in SC-560 group and cisplatin group were 47.1% and 51.7%, respectively, which is significant statistically compared to that of control group (all, P < 0.05). In treatment groups, SC-560 significantly reduced intratumor PGE(2) levels (P < 0.01). MVDs in SC-560 group were 35.73 +/- 9.87, which are significant statistically compared to that of control group (74.33 +/- 9.50) (P < 0.01). COX-1, not COX-2, protein levels are elevated in tumor tissues. These findings may implicate COX-1 as a suitable target for the treatment of ovarian cancer and that antiangiogenic therapy can be used to inhibit ovarian cancer growth.

Aspirin and cancer risk: a summary review to 2007

Aspirin has been associated with a reduced risk of colorectal cancer and--based on limited evidence--to cancers of the oesophagus, stomach, breast, ovary and lung. The role of aspirin on other cancers, such as pancreatic, prostate and bladder cancer and non-Hodgkin's lymphomas and myeloma is less clear, and an increase of risk has been suggested for kidney cancer. For most cancer sites, however, significant heterogeneity between studies, and particularly between study design, was found, with a reduction in risk generally stronger in case-control studies than in cohort ones.

Dietary aspirin decreases the stage of ovarian cancer in the hen

OBJECTIVE

We aimed to determine the effects of dietary aspirin treatment on ovarian cancer incidence and progression in the hen as a model for the human disease.

METHODS

Hens were fed a standard layer diet (control) or the same diet containing 0.1% aspirin for 1 year. Liver prostaglandin E(2) (PGE(2)) was measured using an enzyme immunoassay. Incidence and stage of ovarian cancer were determined through necropsy and immunohistochemical analysis of ovarian sections for each hen.

RESULTS

Aspirin treatment decreased liver PGE(2) in treated hens as compared to control hens. Treatment with aspirin did not decrease ovarian cancer incidence. Significantly more control hens developed late stage ovarian cancer than early stage, while the same was not true for aspirin-treated hens. Hens that developed ovarian cancer, even early ovarian cancer, produced significantly fewer eggs in the year prior to diagnosis than hens without ovarian cancer.

CONCLUSIONS

Aspirin treatment may inhibit the progression of ovarian cancer in the hen and egg production may be used to identify hens with early stages of the disease.

VEGF expression and the effect of NSAIDs on ascites cell proliferation in the hen model of ovarian cancer

OBJECTIVES

We aimed to determine the expression of vascular endothelial growth factor (VEGF) and the effect of nonsteroidal anti-inflammatory drugs (NSAIDs) on the proliferation of cells isolated from ascites in the hen model of ovarian cancer.

METHODS

Ovarian tumor and normal ovary were collected from hens and ascites cells were isolated from hens with ovarian cancer. Quantitative real-time PCR was used to quantify mRNA expression. Immunohistochemical and/or Western blot analyses were used to localize protein expression in ovarian tumors, normal ovaries, and ascites cells. Cells were treated with a nonspecific, COX-1-specific, or COX-2-specific NSAID and proliferation was determined.

RESULTS

VEGF mRNA was increased in ascites cells and there was a trend for a correlation between VEGF mRNA in ascites cells and ascites volume. VEGF protein was localized to theca cells of normal ovaries, in glandular areas of tumors, and to the cytoplasm of ascites cells. Aspirin and a COX-1-specific inhibitor decreased the proliferation of ascites cells, whereas a COX-2-specific inhibitor did not.

CONCLUSIONS

VEGF may play a role in ovarian cancer progression in the hen and the proliferation of ascites cells can be decreased by targeting the COX-1 but not COX-2 pathway.

Inverse association of NSAID use and ovarian cancer in relation to oral contraceptive use and parity

We examined the association between non-steroidal anti-inflammatory drug (NSAID) use and ovarian cancer by potential effect modifiers, parity and oral contraceptive use, in a population-based case–control study conducted in Wisconsin and Massachusetts. Women reported prior use of NSAIDs and information on risk factors in a telephone interview. A total of 487 invasive ovarian cancer cases and 2653 control women aged 20–74 years were included in the analysis. After adjustment for age, state of residence and other covariates, ever use of NSAIDs was inversely associated with ovarian cancer in never users of oral contraceptives (odds ratio (OR)=0.58, 95% confidence interval (CI) 0.42–0.80) but not for ever users (OR=0.98, 95% CI 0.71–1.35) (P-interaction=0.03). A reduced risk with NSAID use was also noted in nulliparous women (OR=0.47, 95% CI 0.27–0.82) but not among parous women (OR=0.81, 95% CI 0.64–1.04) (P-interaction=0.05). These results suggest that use of NSAIDs were beneficial to women at greatest risk for ovarian cancer.

Anti-tumor effect of non-steroidal anti-inflammatory drugs on human ovarian cancers

Many reports have demonstrated that non-steroidal anti-inflammatory drugs (NSAIDs) suppress malignant transformation and tumor growth, and some NSAIDs are expected to be new anti-cancer agents. In this study, we examined the anti-tumor effects of the non-specific cyclooxygenase (COX) inhibitors aspirin and piroxicam, and the selective COX-2 inhibitor meloxicam on xenotransplanted ovarian cancer. Tumor growth and survival were compared in female nu/nu mice, xenografted with subcutaneous OVCAR-3 tumors or with intraperitoneal DISS tumors and treated with aspirin (200 ppm in diet, everyday), piroxicam (150 ppm in diet, everyday) or meloxicam (162 ppm in diet, everyday). Al, of the agents tested significantly suppressed the growth of OVCAR-3 tumors xenotransplanted subcutaneously as compared to the control. There was a significant difference in inhibition of OVCAR-3 tumor growth between meloxicam and aspirin treatment. Meloxicam and piroxicam treatment significantly prolonged survival of mice with malignant ascites derived from DISS cells as compared to control and aspirin treatment. Mice treated with meloxicam survived significantly longer than those treated with piroxicam. There was no significant difference in survival between control and aspirin treatment. Necropsy revealed that one of the 6 cancer-bearing mice treated with piroxicam suffered from stomach perforation. These results indicate that a selective COX-2 inhibitor produces greater anti-tumor effect against ovarian cancer than a nonselective COX inhibitor and that meloxicam may have a potential of leading to a novel therapeutic strategy against ovarian cancer.

[Chemoprevention and prophylactic surgery in ovarian carcinoma]

INTRODUCTION

Ovarian cancer is the leading cause of death from gynaecological malignancy, especially because of late diagnosis. The objective of the study was to provide the clinician with current concepts regarding prevention of ovarian cancer.

MATERIAL AND METHODS

A computerized search of articles published was performed using the Medline database We performed a review of the literature (PubMed, Embase) using the following search terms (MeSH and non-MeSH): prevention, chemoprevention, chemoprevention, ovarian cancer, ovarian, ovary, carcinoma, tumor, tumour.

RESULTS

Oral contraceptive and acetaminophen use may provide substantial protection against ovarian cancer, whereas aspirin, carotenoids and non-steroidal anti-inflammatory agents do not decrease the risk. However, to date, there is no recommendation concerning low risk population. At the opposite, young women (<35-40 years old) presenting with BRCA1 or 2 mutation or Lynch syndrome may be counseled for chemoprevention using oral contraceptive. For high risk women over 35-40 years old, prophylactic bilateral salpingo-oophorectomy should be performed. Indeed, it has been showed that prophylactic surgery significantly decrease mortality rates in high risk women.

CONCLUSION

Large randomized studies are required to assess the efficacy of ovarian cancer chemoprevention in low risk women. High-risk women over 35-40 years old should be counseled for prophylactic salpingo-oophorectomy or for chemoprevention using oral contraceptive.

Cyclooxygenase-2 (cox-2) and the inflammogenesis of cancer

Cohesive scientific evidence from molecular, animal, and human investigations supports the hypothesis that aberrant induction of COX-2 and up-regulation of the prostaglandin cascade play a significant role in carcinogenesis, and reciprocally, blockade of the process has strong potential for cancer prevention and therapy. Supporting evidence includes the following: [1] expression of constitutive COX-2-catalyzed prostaglandin biosynthesis is induced by most cancer-causing agents including tobacco smoke and its components (polycylic aromatic amines, heterocyclic amines, nitrosamines), essential polyunsaturated fatty acids (unconjugated linoleic acid), mitogens, growth factors, proinflammatory cytokines, microbial agents, tumor promoters, and other epigenetic factors, [2] COX-2 expression is a characteristic feature of all premalignant neoplasms, [3] COX-2 expression is a characteristic feature of all malignant neoplasms, and expression intensifies with stage at detection and cancer progression and metastasis, [4] all essential features of carcinogenesis (mutagenesis, mitogenesis, angiogenesis, reduced apoptosis, metastasis, and immunosuppression) are linked to COX-2-driven prostaglandin (PGE-2) biosynthesis, [5] animal studies show that COX-2 up-regulation (in the absence of genetic mutations) is sufficient to stimulate the transformation of normal cells to invasive cancer and metastatic disease, [6] non-selective COX-2 inhibitors, such as aspirin and ibuprofen, reduce the risk of human cancer and precancerous lesions, and [7] selective COX-2 inhibitors, such as celecoxib, reduce the risk of human cancer and precancerous lesions at all anatomic sites thus far investigated. Results confirming that COX-2 blockade is effective for both cancer prevention and therapy have been tempered by observations that some COX2 inhibitors pose a risk to the cardiovascular system, and more studies are needed in order to determine if certain of these drugs can be taken at dosages that prevent cancer without increasing cardiovascular risk. It is emphasized that the "inflammogenesis model of cancer" is not mutually exclusive and may in fact be synergistic with the accumulation of somatic mutations in tumor suppressor genes and oncogenes or epigenetic factors in the development of cancer.

Regular analgesic use and risk of multiple myeloma

Analgesic use has been implicated in the chemoprevention of a number of solid tumors, but to date no previous research has focused on the role of analgesics in the etiology of multiple myeloma (MM). We conducted a hospital-based case-control study of 117 patients with primary, incident MM and 483 age and residence matched controls without benign or malignant neoplasms. All participants received medical services at Roswell Park Cancer Institute in Buffalo, NY, and completed a comprehensive epidemiological questionnaire. Participants who reported analgesic use at least once a week for at least 6 months were classified as regular users; individuals who did not use analgesics regularly served as the reference group throughout the analyses. We used unconditional logistic regression analyses to compute crude and adjusted odds ratios (ORs) with corresponding 95% confidence intervals (CIs). Compared to non-users, regular aspirin users were not at reduced risk of MM (adjusted OR=0.99; 95% CI 0.65-1.49), nor were participants with the highest frequency or duration of aspirin use. A significant risk elevation was found for participants who were regular acetaminophen users (adjusted OR=2.95; 95% CI 1.72-5.08). Further, marked increases in risk of MM were noted with both greater frequency (>7 tablets weekly; adjusted OR=4.36; 95% CI 1.70-11.2) and greater duration (>10 years; adjusted OR=3.26; 95% CI 1.52-7.02) of acetaminophen use. We observed no evidence of a chemoprotective effect of aspirin on MM risk, but observed significant risk elevations with various measures of acetaminophen use. Our results warrant further investigation in population-based case-control and cohort studies and should be interpreted with caution in light of the limited sample size and biases inherent in hospital-based studies.

Association between Nonsteroidal Anti-inflammatory Drug Use and the Incidence of Lung Cancer in the Iowa Women's Health Study

BACKGROUND

Previous studies have suggested that use of aspirin or other nonsteroidal anti-inflammatory drugs (NSAIDs) may be associated with reduced risk of lung cancer, but the data are inconsistent and are limited particularly with respect to the effects of aspirin, separate from other NSAIDs.

METHODS

The Iowa Women's Health Study is a prospective cohort of 41,836 Iowa women ages 55 to 69 years old at baseline in 1986. NSAID use was assessed in 1992. Over 10 years of follow-up, 403 incident cases of lung cancer were identified. The association of incident lung cancer with current use of aspirin or non-aspirin NSAIDs was analyzed after adjustment for lung cancer risk factors. Hazard ratios (HR) were estimated using multivariate COX proportional hazards regression.

RESULTS

There were 27,162 women in the analytic cohort. After controlling for age, education, alcohol intake, pack-years, smoking status, body mass index, and total fruit intake, the RR of women taking six or more aspirin weekly was 1.21 (95% confidence interval, 0.92-1.59). The HR was 1.23 for women taking six or more non-aspirin NSAIDs weekly (95% confidence interval, 0.92-1.65). There was no statistically significant trend by frequency of use for either aspirin (P(trend) = 0.22) or non-aspirin NSAIDs (P(trend) = 0.53). Analyses by histologic type and smoking status yielded similar null results. Information on dosage and duration of use were not available for this analysis.

CONCLUSION

These findings do not suggest that aspirin or other NSAIDs reduce risk of lung cancer in this cohort of postmenopausal women.

Alpha-lipoic acid modulates ovarian surface epithelial cell growth

OBJECTIVE

The intracellular redox state plays an important role in controlling inflammation. Clinical and laboratory data suggest that inflammation can lead to tumor progression. We hypothesized that restoring intracellular redox control would inhibit inflammation and subsequently tumor progression. Our studies were designed to investigate the effect of alpha-lipoic acid (ALA), a naturally occurring antioxidant, on a key inflammatory signaling pathway and cell proliferation in normal and tumorigenic ovarian surface epithelial cells.

METHODS

Normal and tumorigenic ovarian surface epithelial cells were isolated as described by Roby and coworkers [Roby KF, Taylor CC, Sweetwood JP, Cheng Y, Pace JL, Tawpik O, Persons DL, Smith PG, Terranova PF, Development of a syngeneic mouse model for events related to ovarian cancer. Carcinogen 2000;21 (4):585. [1]]. The effect of ALA on cellular function was measured in cell proliferation and apoptosis assays. p27(kip1) protein levels were measured by Western analysis. Activation of NF-kappaB dependent transcription was assessed in cell cultures transiently transfected with NF-kappaB controlled reporter constructs.

RESULTS

Our results reveal that ALA selectively inhibits the growth of tumorigenic as compared to non-tumorigenic ovarian surface epithelial cells. The growth inhibitory effect of ALA is not due to induction of apoptosis but instead is associated with an increase in the half-life of the cyclin-dependent kinase inhibitor, p27(kip1). In parallel to the growth inhibitory effect, ALA also affects a key inflammatory signaling pathway by inhibiting TNFalpha-induced NF-kappaB signaling activity.

CONCLUSIONS

Our studies are the first to show that ALA treatment has a growth inhibitory effect on malignant surface epithelial cells of ovarian origin. We have also confirmed the reproducibility of the immunocompetent mouse ovarian cancer model originally described by Roby and coworkers [Roby KF, Taylor CC, Sweetwood JP, Cheng Y, Pace JL, Tawpik O, Persons DL, Smith PG, Terranova PF, Development of a syngeneic mouse model for events related to ovarian cancer. Carcinogen 2000;21 (4):585].

Aspirin and cancer risk: an updated quantitative review to 2005

Aspirin has been associated to a reduced risk of colorectal, and possibly of a few other common cancers. Epidemiological studies on aspirin and cancer risk published up to December 2005 have been reviewed, and pooled relative risks (RR) for several cancers have been provided. Besides a reduction in the risk of cancer of the colorectum (RR = 0.71, 95% confidence interval, CI: 0.67-0.75), there is evidence-although more limited, and mainly from case-control studies-that aspirin has a favourable effect on cancers of the esophagus (RR = 0.72, 95% CI: 0.62-0.84), stomach (RR = 0.84, 95% CI: 0.76-0.93), breast (RR = 0.91, 95% CI: 0.88-0.95), ovary (RR = 0.89, 95% CI: 0.78-1.02) and lung (RR = 0.94, 95% CI: 0.89-1.00). The role of aspirin on other cancers, such as pancreatic, prostate, bladder cancer, and non-Hodgkins' lymphomas is less clear, and an increase of risk has been suggested for kidney cancer. For most cancer sites, however, significant heterogeneity between studies, and particularly across study design, was found, with a reduction in risk generally stronger in case-control than in cohort studies. Further, notwithstanding the large amount of epidemiological evidence, substantial uncertainties remain about the proper aspirin dose and duration of treatment.

Celecoxib Inhibits Cellular Growth, Decreases Ki-67 Expression and Modifies Apoptosis in Ovarian Cancer Cell Lines

BACKGROUND

There is controversy on the safety of inhibitors of cyclooxygenase administered at high doses; however, these drugs have been reported to be effective in the prevention of a variety of human cancers. To determine if celecoxib influences cellular growth, we evaluated several effects in ovarian carcinoma cell lines.

METHODS

CAOV3, OVCAR3 and SKOV3 cell lines were exposed to different concentrations of celecoxib (0-100 microM) for 24-96 h. Cellular growth was assessed using a cell viability assay. Immunohistochemistry was performed to evaluate Ki-67 and cleaved caspase-3. Apoptosis was determined by a TUNEL assay, and Western blot was used to determine COX-2 protein expression.

RESULTS

We observed a significant decrease in the cellular growth of all cell lines studied exposed to > or = 70 microM of celecoxib for 72 and 96 h (p < 0.02). All cells demonstrated pancytotoxicity at 100 microM of celecoxib. A significant decrease in Ki-67 expression in all cell lines exposed to > or = 30 microM of celecoxib (p < or = 0.05) for 72 h was observed. We observed significant changes in apoptosis and cleaved caspase-3 expression in SKOV3 cells exposed to 50 microM of celecoxib. Downregulation of COX-2 protein expression caused by celecoxib was observed in SKOV3 cells.

CONCLUSIONS

We found that celecoxib inhibits cellular growth and proliferation in a dose-dependent manner in all cell lines studied. SKOV3 cells showed an increase in cleaved caspase-3 expression. Additional studies are in progress to evaluate the effects of celecoxib on other aspects of the control of the cell cycle in cancer cells.

Endometriosis as a model for inflammation–hormone interactions in ovarian and breast cancers

Chronic inflammation has been implicated in a variety of cancers. In this review, we consider associations between endometriosis and cancers both local (ovarian) and distant (breast). We review the epidemiological data linking endometriosis to ovarian and breast cancers. We then consider evidence for a role for sex steroid hormones and for inflammation in the aetiology of each of these cancers. Finally, we consider that endometriosis may promote alterations in sex steroid hormones and inflammatory mediators. A possible explanation for the association between endometriosis and these reproductive cancers may then be local and systemic enhancement of aberrant inflammatory and hormonal mediators. If this hypothesis is true, endometriosis may need to be considered as a risk factor for ovarian and breast cancers, triggering increasingly intensive surveillance. Moreover, treatments for endometriosis may require consideration of the impact on long-term cancer risk.

A Pooled Analysis of 12 Cohort Studies of Dietary Fat, Cholesterol and Egg Intake and Ovarian Cancer

Fat and cholesterol are theorized to promote ovarian carcinogenesis by increasing circulating estrogen levels. Although case-control studies have reported positive associations between total and saturated fat intake and ovarian cancer risk, two cohort studies have observed null associations. Dietary cholesterol and eggs have been positively associated with ovarian cancer risk. A pooled analysis was conducted on 12 cohort studies. Among 523,217 women, 2,132 incident epithelial ovarian cancer cases were identified. Study-specific relative risks (RR) and 95% confidence intervals (CI) were calculated by Cox proportional hazards models, and then pooled using a random effects model. Total fat intake was not associated with ovarian cancer risk (pooled multivariate RR = 1.08, 95% CI 0.86-1.34 comparing > or =45 to 30-<35% of calories). No association was observed for monounsaturated, polyunsaturated, trans-unsaturated, animal and vegetable fat, cholesterol and egg intakes with ovarian cancer risk. A weakly positive, but non-linear association, was observed for saturated fat intake (pooled multivariate RR = 1.29, 95% CI: 1.01-1.66 comparing highest versus lowest decile). Results for histologic subtypes were similar. Overall, fat, cholesterol and egg intakes were not associated with ovarian cancer risk. The positive association for saturated fat intake at very high intakes merits further investigation.

Incessant ovulation, inflammation and epithelial ovarian carcinogenesis: revisiting old hypotheses

Epithelial ovarian cancer (EOC) is often a lethal disease because in many cases early symptoms go undetected. Although research proceeds apace, as yet there are few reliable and specific biomarkers for the early stages of the disease. EOC is an umbrella label for a highly heterogeneous collection of cancers, which includes tumours of low malignant potential, serous cystadenomas, mucinous and clear cell carcinomas, all of which are likely to arise from a number of epithelial cell types and a variety of progenitor lesions. Many, but not all types of EOC are thought to arise from the cells lining ovarian inclusion cysts. In this review, we discuss the hypotheses that have driven our ideas on epithelial ovarian carcinogenesis and examine the morphological and genetic evidence for pathways to EOC. The emergence of laser-capture microdissection and expression profiling by microarray technologies offers the promise of defining these pathways more accurately, as well as providing us with the tools for earlier diagnosis.

Opposing effects of aspirin and acetaminophen use on risk of adult acute leukemia

Regular use of aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) has been hypothesized to be associated with reduced risk of hematologic cancer, although previous results have been inconsistent. The current study investigated the effects of aspirin or acetaminophen use on adult acute leukemia risk among 169 individuals with leukemia and 676 age and sex matched hospital controls with non-neoplastic conditions who completed a comprehensive epidemiologic questionnaire. Results indicate that regular aspirin use may be associated with a modest decrease in leukemia risk [adjusted odds ratio (aOR), 0.84; 95% confidence interval (CI), 0.59-1.21]. In contrast, ever using acetaminophen was associated with elevated leukemia risk (aOR, 1.53; 95% CI, 1.03-2.26). Results did not differ between men and women. Other studies have demonstrated that acetaminophen is associated with transient decreases in DNA repair, and lymphocytes may be particularly susceptible to DNA damage, suggesting a mechanism for the elevated acute leukemia risk observed among acetaminophen users.

Do nonsteroidal anti-inflammatory drugs affect the risk of developing ovarian cancer? A meta-analysis

AIM

The relationship between the use of nonsteroidal anti-inflammatory drugs (NSAIDs), including aspirin, and the risk of ovarian cancer has been controversial. This study examines the strength of this association by conducting a detailed meta-analysis of the studies published in peer-reviewed literature on the subject.

METHODS

A comprehensive search for articles published up to April 2004 was performed, reviews of each study were conducted and data were abstracted. Prior to meta-analysis, the studies were evaluated for publication bias and heterogeneity. Pooled relative risk estimates (RR) and 95% confidence intervals (CIs) were calculated.

RESULTS

Ten reports (six case-control and four cohort studies), published between 1998 and 2004, were identified. There was no evidence of an association between aspirin use and ovarian cancer risk either assuming a random-effects model (RR = 0.92, 95% CI 0.80, 1.06), or a fixed-effects model (RR = 0.93, 95% CI 0.81, 1.06). Similarly, we did not find evidence of an association between non-aspirin NSAID use and ovarian cancer, both on the basis of a random-effects model (RR = 0.86, 95% CI 0.68, 1.08), and on the basis of a fixed-effects model (RR = 0.88, 95% CI 0.76, 1.01). When the analyses were stratified into subgroups, there was no evidence that study design substantially influenced the estimate of effects. Furthermore, our analysis did not show decreasing risks with increasing frequency or duration of use, features often associated with causal relationships.

CONCLUSIONS

Our meta-analysis findings do not support that NSAID use plays a role in the chemoprevention of ovarian cancer. Future research should examine potential relationships between specific NSAIDs and ovarian cancer, taking into account the possible biases that may have affected this meta-analysis.

Regular aspirin use and esophageal cancer risk

Given the high mortality rate and the rapidly increasing incidence rate of esophageal carcinoma, chemopreventive agents are highly desirable. Aspirin has been shown to be associated with reduced risk of developing colorectal carcinoma and other cancers. Even though previous studies have shown reduced risk of esophageal cancer associated with aspirin use, results were inconsistent with respect to frequency and duration of use. In this hospital-based case-control study, 163 esophageal cancer cases were compared to 482 age- and sex-matched hospital controls with nonneoplastic conditions. Participants were classified as regular aspirin users if they had taken the drug at least once a week for 6 months. Results suggest that esophageal cancer risk is significantly lower for regular aspirin users compared to nonusers [adjusted odds ratio (aOR) 0.54; 95% confidence interval (CI) 0.36-0.86]. Individuals who used an equivalent of at least 1 aspirin a day (> or =7 tablets/week) were half as likely to have been diagnosed with esophageal carcinoma (aOR 0.47; 95% CI 0.26-0.85), and a linear trend was noted with increasing frequency of use (p(trend) 0.007). Similar protective effects were noted with < or =20 years of use, whereas no risk reduction was noted with >20 years of use. Consistent reduction in risk associated with aspirin use was noted among both the major histological subtypes, but the protective effect appears to be more pronounced in adenocarcinoma compared to squamous cell carcinoma. Overall, results from the current study suggest that regular aspirin use may be associated with reduced risk of esophageal cancer.

Selective induction of cyclooxygenase-2 plays a role in lysophosphatidic acid regulated Fas ligand cell surface presentation

Previous studies found that lysophosphatidic acid (LPA) upregulated Fas ligand (FasL) presentation on the ovarian cancer cell surface and lead to apoptosis of activated lymphocytes. In this report, we investigated the role of selective induction of cyclooxygenase-2 (Cox-2) in FasL cell surface presentation stimulated by LPA. Ovarian cancer cells pretreated with general aspirin derivative acetylsalicylic acid and specific Cox-2 inhibitor (NS-398) before stimulation with LPA, FasL cell surface presentation was significantly blocked, so was the apoptosis of activated lymphocytes mediated by increasing FasL on the ovarian cancer cell surface. Using the specific inhibitors PD98059, AG1478 or dominant-negative epidermal-growth-factor receptor (EGFR-DN) plasmid, we found that the activation of ERK1/2 played a role in Cox-2 induction, and the transactivation of EGFR worked as an upstream signaling pathway in ERK1/2 phosphorylation. This study first revealed the selective induction of Cox-2 by LPA led to FasL presentation on ovarian cancer cell surface and provide cancer cell immune privilege, and might provide important information of Cox-2 in cancer progression and Cox-2 inhibitors' application in cancer chemoprevention.

Inflammation and Endometrial Cancer: A Hypothesis

Endometrial cancer is the most common gynecologic malignancy in the United States. Substantial epidemiologic data implicate an imbalance of estrogens and progestogens in the etiology of this disease. We propose that inflammation also plays a role in endometrial cancer development. Emerging laboratory data suggest that elevated levels of prostaglandin E(2) may underlie the transformation of normal endometrium to neoplastic tissue and that in vitro nonsteroidal anti-inflammatory drugs may inhibit endometrial cancer cell growth. In this review, we suggest that the risk factors for endometrial cancer--unopposed estrogens, anovulation, polycystic ovary syndrome, excessive menstruation, early menarche, and late menopause--may be viewed as factors increasing the exposure of the endometrium to inflammation, whereas pregnancy and smoking, two likely protective factors, have the opposite effect. Chronic inflammation can induce rapid cell division, increasing the possibility for replication error, ineffective DNA repair, and subsequent mutations. A proinflammatory milieu can also directly increase estrogen production. Hence, inflammation may work in conjunction with or in addition to estrogen exposure in the development of endometrial cancer.

Regular Analgesic Use and Risk of Endometrial Cancer

BACKGROUND

Analgesic use has been implicated in the chemoprevention of a number of solid tumors, but thus far, no previous research has focused on the role of aspirin in endometrial cancer etiology.

METHODS

We conducted a hospital-based case-control study of 427 women with primary, incident endometrial cancer, and 427 age- and residence-matched controls without benign or malignant neoplasms. All participants received medical services at Roswell Park Cancer Institute in Buffalo, NY, and completed a comprehensive epidemiologic questionnaire. Women who reported analgesic use at least once a week for at least 6 months were classified as regular users and served as the reference group throughout the analyses. We used unconditional logistic regression analyses to compute crude and adjusted odds ratios (OR) with corresponding 95% confidence intervals (CI).

RESULTS

Compared with nonusers, regular aspirin users were not at reduced risk of endometrial cancer (adjusted OR, 0.91; 95% CI, 0.66-1.26), nor were women with the highest frequency, duration, or cumulative lifetime aspirin use. When the sample was divided by body mass index status, regular aspirin use was not associated with risk among women classified as normal weight or overweight, but a significant risk reduction was seen for obese women (adjusted OR, 0.50; 95% CI, 0.27-0.92). Significant decreases in risk were also observed for obese women with the greatest frequency, duration, and cumulative aspirin use. No significant associations in the overall sample or among obese women were noted for acetaminophen use.

CONCLUSION

We observed no evidence of an overall chemoprotective effect of aspirin on endometrial cancer risk, but the significant risk reductions among obese women warrant further investigation.