Novel monofunctional platinum (II) complex Mono-Pt induces apoptosis-independent autophagic cell death in human ovarian carcinoma cells, distinct from cisplatin

Failure to engage apoptosis appears to be a leading mechanism of resistance to traditional platinum drugs in patients with ovarian cancer. Therefore, an alternative strategy to induce cell death is needed for the chemotherapy of this apoptosis-resistant cancer. Here we report that autophagic cell death, distinct from cisplatin-induced apoptosis, is triggered by a novel monofunctional platinum (II) complex named Mono-Pt in human ovarian carcinoma cells. Mono-Pt-induced cell death has the following features: cytoplasmic vacuolation, caspase-independent, no nuclear fragmentation or chromatin condensation, and no apoptotic bodies. These characteristics integrally indicated that Mono-Pt, rather than cisplatin, initiated a nonapoptotic cell death in Caov-3 ovarian carcinoma cells. Furthermore, incubation of the cells with Mono-Pt but not with cisplatin produced an increasing punctate distribution of microtubule-associated protein 1 light chain 3 (LC3), and an increasing ratio of LC3-II to LC3-I. Mono-Pt also caused the formation of autophagic vacuoles as revealed by monodansylcadaverine staining and transmission electron microscopy. In addition, Mono-Pt-induced cell death was significantly inhibited by the knockdown of either BECN1 or ATG7 gene expression, or by autophagy inhibitors 3-methyladenine, chloroquine and bafilomycin A 1. Moreover, the effect of Mono-Pt involved the AKT1-MTOR-RPS6KB1 pathway and MAPK1 (ERK2)/MAPK3 (ERK1) signaling, since the MTOR inhibitor rapamycin increased, while the MAPK1/3 inhibitor U0126 decreased Mono-Pt-induced autophagic cell death. Taken together, our results suggest that Mono-Pt exerts anticancer effect via autophagic cell death in apoptosis-resistant ovarian cancer. These findings lead to increased options for anticancer platinum drugs to induce cell death in cancer.

Challenges of pelvic imaging in obese women

Obesity is a major global health concern affecting all ages, socioeconomic groups, and countries. Although men have higher rates of overweight, women have higher rates of obesity. In the United States, more than 60% of women are overweight or obese, with slightly more than one-third considered frankly obese. Obesity is a major risk factor for noncommunicable diseases such as diabetes mellitus, cardiovascular disease, hypertension, stroke, and specific cancers. Obesity is associated with increased mortality for all cancers, with the highest death rates occurring in the heaviest women. Obesity can contribute to missed diagnoses, nondiagnostic results of imaging studies, imaging examination cancellation because of weight or girth restrictions, scheduling of inappropriate examinations, and increased radiation dose exposure. The utility of the clinical examination is often limited in the obese woman, which results in an even greater reliance on imaging; however, the obese woman may experience a lowered quality of and less access to medical imaging. Recognition of equipment limitations, imaging artifacts, optimization techniques, and appropriateness of modality choices is critical to providing good patient care to this health-challenged group. The clinical indication, the patient's weight, and the body diameters are three key factors to consider when choosing the most appropriate examination. Familiarity with the optimization of imaging techniques across all modalities is important to convert potentially suboptimal examinations into diagnostic-quality studies. The aim of this review is to identify key areas in which obesity affects the imaging care of women with pelvic conditions and to outline strategies to address these areas.

Reproductive factors for ovarian cancer in southern Chinese women

Objective

To investigate the association between reproductive factors and the risk of ovarian cancer among southern Chinese women.

Methods

A hospital-based case-control study was undertaken in Guangzhou, Guangdong Province, between 2006 and 2008. A structured questionnaire was used to obtain information on parity, oral contraceptive use and other reproductive factors in a sample of 500 incident ovarian cancer patients and 500 controls (mean age, 59 years). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using unconditional logistic regression models.

Results

High parity was inversely associated with ovarian cancer, with an adjusted OR 0.43 (95% CI, 0.30 to 0.62) for women who had given birth to 3 or more children compared to women who had given no more than one birth. Ever use of oral contraceptives was also protective against ovarian cancer; adjusted OR 0.56 (95% CI, 0.40 to 0.78). No association was found for hormone replacement therapy, menopausal status, hysterectomy and family history of ovarian and/or breast cancer.

Conclusion

High parity and oral contraceptive use are associated with a lower risk of ovarian cancer in southern Chinese women.

Ovarian cancer risk is reduced by prolonged lactation: a case-control study in southern China

BACKGROUND

Ovarian cancer is an important neoplasm that is difficult to diagnose and treat; therefore, prevention is the preferable strategy. Growing evidence indicates a protective effect of breastfeeding on ovarian cancer risk.

OBJECTIVE

The objective was to investigate the association between lactation and the risk of ovarian cancer among southern Chinese women.

DESIGN

A case-control study was undertaken in Guangzhou, Guangdong Province, between August 2006 and July 2008. A validated and reliable questionnaire was used to obtain information on the months of lactation and number of children breastfed in a sample of 493 incident ovarian cancer patients and 472 hospital-based controls (mean age: 59 y). Logistic regression analyses were performed to assess the association between breastfeeding and the risk of ovarian cancer.

RESULTS

Significant inverse dose-response relations were found for both duration of lactation and the number of children breastfed. The adjusted ORs were 0.09 (95% CI: 0.04, 0.19) for women with ≥31 mo of total lactation and those with ≤10 mo of lactation and 0.38 (95% CI: 0.27, 0.55) for women with ≥3 children breastfed compared with those with one child breastfed.

CONCLUSION

Prolonged lactation is associated with a lower risk of ovarian cancer in parous Chinese women.

Microvesicles as potential ovarian cancer biomarkers

Although the incidence of ovarian cancer is low (i.e., less than 5% in European countries), it is the most lethal gynecologic malignancy and typically has a poor prognosis. To ensure optimal survival, it is important to diagnose this condition when the pathology is confined to the ovary. However, this is difficult to achieve because the first specific symptoms appear only during advanced disease stages. To date, the biomarker mainly used for the diagnosis and prognosis of ovarian cancer is CA125; however, this marker has a low sensitivity and specificity and is associated with several other physiological and pathological conditions. No other serum ovarian cancer markers appear to be able to replace or complement CA125, and the current challenge is therefore to identify novel markers for the early diagnosis of this disease. For this purpose, studies have focused on the microvesicles (MVs) released from tumor cells. MVs may represent an ideal biomarker because they can be easily isolated from blood, and they have particular features (mainly regarding microRNA profiles) that strongly correlate with ovarian cancer stage and may be effective for early diagnosis.

Immunohistochemical investigation of the correlation between LIM kinase 1 expression and development and progression of human ovarian carcinoma

OBJECTIVES

LIM kinase 1 (LIMK1) is implicated in cellular mechanisms regulating tumour cell invasion and may be involved in ovarian carcinoma progression. This retrospective study, therefore, investigated expression of the LIMK1 gene in primary ovarian tumour tissue samples and evaluated the correlation between LIMK1 gene expression and progression of ovarian carcinoma.

METHODS

LIMK1 protein levels were detected by immunohistochemistry in ovarian tissue samples from 57 patients with primary ovarian epithelial tumours (benign, n = 13; borderline, n = 14; carcinoma, n = 30) and 10 patients with normal ovaries. LIMK1 protein levels were evaluated by calculating the product of the scores for stain intensity and percentage of cells stained.

RESULTS

There was a significant correlation between increasing LIMK1 protein levels and increasing disease severity, from normal ovarian tissues through benign and borderline tumours to ovarian carcinoma. There was also a significant correlation between increasing LIMK1 protein levels and increasingly poor levels of differentiation of ovarian carcinoma.

CONCLUSIONS

LIMK1 is associated with the development of ovarian cancer and with the level of tumour differentiation in patients with ovarian carcinoma.

Gold nanorods for ovarian cancer detection with photoacoustic imaging and resection guidance via Raman imaging in living mice

Improved imaging approaches are needed for ovarian cancer screening, diagnosis, staging, and resection guidance. Here, we propose a combined photoacoustic (PA)/Raman approach using gold nanorods (GNRs) as a passively targeted molecular imaging agent. GNRs with three different aspect ratios were studied. Those with an aspect ratio of 3.5 were selected for their highest ex vivo and in vivo PA signal and used to image subcutaneous xenografts of the 2008, HEY, and SKOV3 ovarian cancer cell lines in living mice. Maximum PA signal was observed within 3 h for all three lines tested and increased signal persisted for at least two days postadministration. There was a linear relationship (R(2) = 0.95) between the PA signal and the concentration of injected molecular imaging agent with a calculated limit of detection of 0.40 nM GNRs in the 2008 cell line. The same molecular imaging agent could be used for clear visualization of the margin between tumor and normal tissue and tumor debulking via surface-enhanced Raman spectroscopy (SERS) imaging. Finally, we validated the imaging findings with biodistribution data and elemental analysis. To the best of our knowledge, this is the first report of in vivo imaging of ovarian cancer tumors with a photoacoustic and Raman imaging agent.

Plasma concentrations of the vitamin E-binding protein afamin are associated with overall and progression-free survival and platinum sensitivity in serous ovarian cancer--a study by the OVCAD consortium

OBJECTIVE

Comparative proteomics identified the plasma protein afamin as potential biomarker for ovarian cancer (OC). Significantly decreased afamin plasma concentrations in pre-therapeutic OC patients reconstituted to control values after successful tumor surgery. This study evaluates the association of afamin with survival and response to therapy in serous OC patients within the OVCAD consortium project.

METHODS

We measured afamin in 215 pre-therapeutic plasma samples, 246 tumor lysates and 109 plasma samples taken 6months after finishing platinum-based chemotherapy. Differences in afamin plasma concentrations among FIGO stages were tested by Kruskal-Wallis test; association of afamin concentrations with overall and progression-free survival was evaluated using Kaplan-Meier survival plots and multivariate adjusted COX regression analysis.

RESULTS

Pre-therapeutic afamin correlated significantly with FIGO stages (p=0.012) and was lower in the presence of metastases (p=0.013) and poorly differentiated OC in patients responding to therapy (p=0.016). Afamin ≥48.0mg/L was also associated with a lower hazard ratio for recurrent disease as compared to afamin <48.0mg/L (p=0.007). Post-therapeutic afamin ≥48mg/L was positively correlated with overall (p<0.001) and progression-free (p=0.012) survival and was lower in non-responders than in responders (p=0.048). Thus, afamin returned post-therapeutically to values of healthy controls in responders (p<0.001) but not in non-responders (p=0.114). Afamin in tumor lysates was lower in poorly differentiated OC than in G 1+2 tumors (p=0.041). Higher afamin concentrations in tumor lysates were associated with increased overall survival (p=0.003).

CONCLUSION

These data indicate that afamin is associated with therapy response and survival rate in advanced OC patients.

Expression of cofilin 1 is positively correlated with the differentiation of human epithelial ovarian cancer

The aim of this study was to examine the correlation between cofilin 1 expression and differentiation of epithelial ovarian cancer in patients. We immunohistochemically analyzed 30 patients with primary ovarian epithelial carcinomas, 14 patients with borderline epithelial ovarian tumors, 13 patients with benign epithelial ovarian tumors and 10 normal ovarian tissues. All ovarian cancer patients received the standard therapy, including staging laparotomy and adjuvant chemotherapy consisting of carboplatin and paclitaxel. Cofilin 1 expression gradually increased in normal ovarian tissues, benign tumors, borderline tumors and carcinomas, respectively, and there were significant differences among them (r= 0.94, P<0.05). This suggests a positive correlation between the expression of cofilin 1 and tumor differentiation (r= 0.97, P<0.05). The expression of cofilin 1 may predict the development of ovarian cancer and may be involved in the progression of patients with ovarian carcinoma.

Detection of novel biomarkers for ovarian cancer with an optical nanotechnology detection system enabling label-free diagnostics

Ovarian carcinoma has the highest lethality rate of gynecologic tumors, largely attributed to the late-stage diagnosis of the disease. Reliable tools for both accurate diagnosis and early detection of disease onset are lacking, and presently less than 20% of ovarian cancers are detected at an early stage. Protein biomarkers that allow the discrimination of early and late stages of ovarian serous carcinomas are urgently needed as they would enable monitoring pre-symptomatic aspects of the disease, disease progression, and the efficacy of intervention therapies. We compare the absolute and relative protein levels of six protein biomarkers for ovarian cancer in five different established ovarian cancer cell lines, utilizing both quantitative immunoblot analysis and a guided-mode resonance (GMR) bioassay detection system that utilizes a label-free optical biosensor readout. The GMR sensor approach provided highly accurate, consistent, and reproducible quantification of protein biomarkers as validated by quantitative immunoblotting, as well as enhanced sensitivity, and is therefore suitable for quantification and detection of novel biomarkers for ovarian cancer. We identified fibronectin, apolipoprotein A1, and TIMP3 as potential protein biomarkers for the differential diagnosis of primary versus metastatic ovarian carcinoma. Future studies are needed to confirm the suitability of protein biomarkers tested herein in patient samples.

Immunosignaturing can detect products from molecular markers in brain cancer

Immunosignaturing shows promise as a general approach to diagnosis. It has been shown to detect immunological signs of infection early during the course of disease and to distinguish Alzheimer’s disease from healthy controls. Here we test whether immunosignatures correspond to clinical classifications of disease using samples from people with brain tumors. Blood samples from patients undergoing craniotomies for therapeutically naïve brain tumors with diagnoses of astrocytoma (23 samples), Glioblastoma multiforme (22 samples), mixed oligodendroglioma/astrocytoma (16 samples), oligodendroglioma (18 samples), and 34 otherwise healthy controls were tested by immunosignature. Because samples were taken prior to adjuvant therapy, they are unlikely to be perturbed by non-cancer related affects. The immunosignaturing platform distinguished not only brain cancer from controls, but also pathologically important features about the tumor including type, grade, and the presence or absence of O⁶-methyl-guanine-DNA methyltransferase methylation promoter (MGMT), an important biomarker that predicts response to temozolomide in Glioblastoma multiformae patients.

Impact of screening test performance and cost on mortality reduction and cost-effectiveness of multimodal ovarian cancer screening

Ongoing ovarian cancer screening trials are investigating the efficacy of a two-step screening strategy using currently available blood and imaging tests [CA125 and transvaginal sonography (TVS)]. Concurrently, efforts to develop new biomarkers and imaging tests seek to improve screening performance beyond its current limits. This study estimates the mortality reduction, years of life saved, and cost-effectiveness achievable by annual multimodal screening using increasing CA125 to select women for TVS, and predicts improvements achievable by replacing currently available screening tests with hypothetical counterparts with better performance characteristics. An existing stochastic microsimulation model is refined and used to screen a virtual cohort of 1 million women from ages 45 to 85 years. Each woman is assigned a detailed disease course and screening results timeline. The preclinical behavior of CA125 and TVS is simulated using empirical data derived from clinical trials. Simulations in which the disease incidence and performance characteristics of the screening tests are independently varied are conducted to evaluate the impact of these factors on overall screening performance and costs. Our results show that when applied to women at average risk, annual screening using increasing CA125 to select women for TVS achieves modest mortality reduction (~13%) and meets currently accepted cost-effectiveness guidelines. Screening outcomes are relatively insensitive to second-line test performance and costs. Identification of a first-line test that does substantially better than CA125 and has similar costs is required for screening to reduce ovarian mortality by at least 25% and be reasonably cost-effective.

Anti-KDEL-coated nanoparticles: a promising tumor targeting approach for ovarian cancer?

The purpose of this study was to target ovarian cancer cells by coupling paclitaxel (Tx)-loaded nanoparticles (NPs-Tx) to antibodies against KDEL sequence, able to recognize GRP94 and GRP78 that are located at cell surface in cancer cells whereas they are in the endoplasmic reticulum in healthy cells. Tx-loaded poly (DL-lactic acid) nanoparticles coated with anti-KDEL antibodies (NPs-Tx-KDEL) were successfully prepared and characterized. Interaction between tumor cells and NPs-Tx or NPs-Tx-KDEL was observed by microscopy with fluorescently labeled NPs and the efficacy of the different formulations was compared by a viability assay. Particles functionalized with monoclonal antibodies (mAb) showed a higher binding to the cells even though the internalization rate appeared limited. The effect of NPs-Tx-KDEL on cell viability (proliferation) was compared to Tx, NPs, NPs-Tx, anti-KDEL mAb or anti-KDEL mAb in combination with NPs-Tx in Bg-1 ovarian cell line. Our data indicate that NPs-Tx-KDEL significantly increase sensitivity of Bg-1 cells to Tx compared to other treatments. This study confirms the interest of anti-cancer therapy by targeting cell surface GRP78 and GRP94 on cancer cells, and demonstrates the efficiency of coupling KDEL antibodies to NPs.

Translational genomics: the challenge of developing cancer biomarkers

Early detection and definitive treatment of cancer have been shown to decrease death and suffering in epidemiologic and intervention studies. Application of genomic approaches to many malignancies has produced thousands of candidate biomarkers for detection and prognostication, yet very few have become established in clinical practice. Fundamental issues related to tumor heterogeneity, cancer progression, natural history, and biomarker performance have provided challenges to biomarker development. Technical issues in biomarker assay detection limits, specificity, clinical deployment, and regulation have also slowed progress. The recent emergence of biomarkers and molecular imaging strategies for treatment selection and monitoring demonstrates the promise of cancer biomarkers. Organized efforts by interdisciplinary teams will spur progress in cancer diagnostics.

HE4 combined with MDCT imaging is a good marker in the evaluation of disease extension in advanced epithelial ovarian carcinoma

The purpose of the study was to evaluate the expression of the biomarkers CA125 and HE4 combined with imaging, in patients with advanced epithelial ovarian cancer (EOC). Forty-six women with EOC were included in the study all affected with peritoneal carcinomatosis. Twenty-two of 46 patients (group I) had peritoneal carcinomatosis with small implants in single or in multiple sites (score 1); 24/46 patients (group II) had macro-nodular implants and omental thickening (score 2). High levels of CA125 (350 ± 11, mean ± SEM) have been observed in 21/22 patients of group I, and a similar value (370 ± 13) has been observed in all patients belonging to group II. HE4 positivity values (350 ± 9) have been observed in all group I patients, whereas all patients belonging to group II showed a higher value of HE4 (600 ± 12). Statistically significant differences were observed between the HE4 levels observed in group I patients in comparison with group II patients (p < 0.0001). In addition, we expressed the extension of lymph nodal disease in three scores: L1-L2-L3, and a statistically significant correlation was observed between high HE4 levels and severity of lymph nodal disease L3 (p < 0.0001). The availability of biomarkers, particularly HE4, together with sophisticated imaging techniques, strengthens the clinical relevance of this study, for the follow-up of patients with peritoneal carcinomatosis.