nm23 gene polymorphisms are associated with survival of patients with epithelial ovarian cancer but not with susceptibility to disease

Objective

nm23, a tumor metastasis suppressor gene, has been linked to protection against tumorigenesis and tumor metastasis. This study evaluated whether genetic variants in the nm23 gene were associated with susceptibility to epithelial ovarian cancer (EOC) or the clinical outcome of patients.

Methods

A case-control study was performed with 302 patients with epithelial ovarian cancer and 302 control women. According to the genotypes, the outcome in 213 EOC patients was compared. Progression-free survival (PFS) and overall survival (OS) were analyzed with Kaplan-Meier plots and Cox models adjusted for clinical factors.

Results

The case-control analysis showed that the rs16949649 and rs2302254 polymorphisms in the nm23 gene promoter were not associated with the risk of developing EOC. In contrast, survival analysis showed that the rs2302254 C/T polymorphism was related to the prognosis of EOC patients. Compared with patients carrying the C/C genotype, patients carrying the T/T genotype had a shorter median PFS and median OS by Kaplan-Meier plots and Cox models adjusted for clinical factors. For rs16949649 T/C polymorphisms, Kaplan-Meier analysis indicated that patients carrying the homozygous C/C genotype had shorter PFS and OS than those carrying the T allele (T/T + T/C genotype). The Cox proportional hazard model analysis suggested that this relationship was only retained in OS when adjusted for clinical factors.

Conclusion

Our studies suggest that rs16949649 and rs2302254 polymorphisms in the nm23 gene promoter may influence the prognosis of patients with epithelial ovarian cancer.     

MMP-1-PAR1 axis mediates LPA-induced epithelial ovarian cancer (EOC) invasion

Objectives

MMP-1 is over-expressed in many cancers, with high expression often associated with poor survival. In the present study, we examined the expression of MMP-1 in EOC and its role in EOC invasion. Moreover, we evaluated the role of a newly identified MMP-1-protease activated receptor (PAR)-1 axis in LPA-induced EOC invasion.

Methods

MMP-1 and PAR1 mRNA expression in EOC cell lines was determined by real time PCR. MMP-1 mRNA expression in 96 normal and carcinoma ovarian tissue specimens was analyzed using a TissueScan real time PCR array. MMP-1 concentration in conditioned medium was measured by MMP-1 ELISA. PAR1 protein expression was detected by Western blotting. Cell invasion was evaluated by in vitro Matrigel invasion assay.

Results

In ovarian tumor tissues more MMP-1 expression was observed than in normal ovarian tissues (p < 0.05), and its expression correlated with tumor grade (grade 3 > grade 2 > grade 1). Human recombinant MMP-1 as well as serum free conditioned medium containing high levels of MMP-1 from DOV13 and R182 cells significantly promoted DOV13 cell invasion (p < 0.05), implicating a direct role of MMP-1 in EOC invasion. Moreover, MMP-1 induced DOV13 invasion was significantly blocked by PAR1 siRNA silencing. Furthermore, MMP-1 and PAR1 were both significantly induced by LPA (20 μM), and siRNA silencing of MMP-1 and PAR1 both significantly reduced LPA's invasion-promoting effect in DOV13 cells (p < 0.05).

Conclusions

Our results suggest that the MMP-1-PAR1 axis is involved in EOC invasion and at least partially mediates LPA-induced EOC invasion. Therefore, blocking MMP-1 or PAR1 may represent a new therapeutic option for metastatic EOC.     

Expression of 67-kDa laminin receptor was associated with tumor progression and poor prognosis in epithelial ovarian cancer

Objective

67-kDa laminin receptor (67LR) has been identified as a prognostic biomarker for a variety of human cancers. We investigated the clinical significance of 67LR expression and its functional role in epithelial ovarian cancer (EOC).

Methods

67LR expression was evaluated by immunohistochemistry in 62 patients with EOC. We assessed the correlation of 67LR expression with clinical characteristics. In vitro experiment was performed for 67LR with inhibition using siRNA to evaluate its role in cell survival, apoptosis, and invasion in EOC cells.

Results

67LR was predominantly expressed on the cell membrane in the majority of EOC samples (45/62, 73%). 67LR expression was significantly correlated with advanced stage (P = 0.001). Patients with 67LR expression had shorter progression-free survival among all the patients (P = 0.010) and in particular among patients with advanced stages (P = 0.046). When 67LR expression was inhibited by siRNA in EOC cells (HeyA8 and A2780), there was a significant decrease of cell proliferation and invasion as well as increase of apoptosis.

Conclusion

These findings suggest that 67LR expression may play an important role in tumor progression into advanced stage with poor prognosis in EOC and down-regulation of 67LR on tumor cells may be a therapeutic target in those patients.     

FDG PET/CT in staging of advanced epithelial ovarian cancer: frequency of supradiaphragmatic lymph node metastasis challenges the traditional pattern of disease spread

Objective

Epithelial ovarian cancer (EOC) spreads intra-abdominally and to the retroperitoneal lymph nodes. A greater number of distant metastases are revealed by ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) compared to conventional imaging methods. We aimed to investigate the presence and anatomic distribution of supradiaphragmatic lymph node metastasis (LNM) detected with pretreatment FDG PET/CT.

Methods

Thirty women with advanced stage (IIC-IV) EOC were scanned with whole body contrast-enhanced FDG PET/CT prior to surgery/neoadjuvant chemotherapy. We performed PET/CT analysis qualitatively and quantitatively. Additionally, contrast-enhanced CT was analyzed blinded to PET/CT scan. Intra-abdominal dissemination was verified by surgery and histopathology. Metabolically active lymph nodes were biopsied when possible. The clinical characteristics of patients with and without supradiaphragmatic LNM were compared.

Results

In 20/30patients (67%) FDG PET/CT detected supradiaphragmatic LNM in one or more locations, whereas conventional CT found LNM in 10 patients (33%). Fourteen patients had parasternal, 14 cardiophrenic, 8 other mediastinal, 6 axillar, and 1 subclavian LNM. Microscopy of all four biopsied lymph nodes (three axillar and one subclavian) confirmed metastatic dissemination. The patients with supradiaphragmatic LNM had significantly more ascites (p < 0.01), higher CA 125 levels, and more frequent subdiaphragmal carcinomatosis (p < 0.03) compared to patients without supradiaphragmatic LNM in preoperative FDG PET/CT.

Conclusions

A significant number of patients with advanced EOC showed supradiaphragmatic LNM in pre-treatment PET/CT. Our findings suggest that the route of EOC cells from the peritoneal cavity to the lymphatic system permeates the diaphragm mainly to the cardiophrenic and continues to parasternal lymph nodes.     

Lymphatic ascites following pelvic and paraaortic lymphadenectomy procedures for gynecologic malignancies

Objective

Lymphatic ascites is an unusual complication in patients with cancer. In the gynecologic oncology patient population, the most common etiology is operative lymph node dissection. The purpose of this study was to explore the incidence, presenting symptoms, methods of diagnosis and treatment modalities utilized for lymphatic ascites in patients undergoing lymph node dissection for gynecologic cancers.

Methods

This observational study retrospectively reviewed the charts of patients who underwent lymphadenectomy as part of the surgical management for a gynecologic cancer. Patients that developed postoperative lymphatic ascites between January 2000 and December 2010 were included for analysis. Data extracted from the medical records included tumor pathology, number of harvested lymph nodes, postoperative course, method of diagnosis and treatment.

Results

From a total of 300 surgical staging procedures, 12 patients with lymphatic ascites were identified (4%). The most common reported symptom was leakage of clear fluid per vagina (7, 58%), followed by abdominal distension (4, 33%). The median interval from surgery to development of symptoms was 12.5 days (range 0-22 days). 5 patients had complete resolution of symptoms with dietary modifications alone while 7 patients required paracentesis. The median time from surgery to resolution of symptoms was 44 days (range 9-99).

Conclusion

Lymphatic ascites is an under recognized and infrequently reported postoperative complication. Although it usually resolves spontaneously or with conservative management without sequelae, this condition can significantly prolong postoperative recovery and cause patient discomfort. To our knowledge this is the largest group of patients undergoing gynecologic surgical staging procedures to be reviewed for the occurrence of lymphatic ascites.     

Elafin selectively regulates the sensitivity of ovarian cancer cells to genotoxic drug-induced apoptosis

Objective

Elafin has been reported to be abundantly expressed in human epithelial ovarian carcinoma (EOC), however, its functions are poorly understood. Here, we evaluated the role of elafin in modulating the sensitivity of human EOC cells to chemotherapeutic drugs.

Methods

Elafin expression was determined by ELISA in 9 established human EOC cell lines. A lentivirus encoding elafin-specific shRNA was used to down-regulate elafin expression in OVCAR3 and OV433 cells, and a plasmid encoding elafin was used to ectopically express elafin in elafin-negative SKOV3 cells. Sensitivity to cisplatin and other genotoxic agents and to paclitaxel, an inhibitor of microtubule depolymerization, was examined in OVCAR3, OV433 and SKOV3 sublines. Cell viability was determined by the MTT assay, apoptosis by annexin V/7-AAD staining and caspase activation by fluorimetric assay.

Results

Knockdown of the elafin gene decreases cisplatin IC50 by at least 2-folds in OVCAR3 and OVCAR433 cells (p < 0.01) but does not affect paclitaxel IC50. The sensitivity to other genotoxic agents such as carboplatin, cyclophosphamide and 5-fluorouracil was also increased by silencing the expression of elafin. Apoptosis and caspase-3 activation were significantly augmented in cisplatin-treated OVCAR3 cells with silenced elafin. Overexpression of elafin in SKOV3 cells made them more resistant to cisplatin and decreased cisplatin-induced apoptosis and caspase activation (p < 0.01).

Conclusions

Expression of elafin decreases the sensitivity of human EOC cells to several genotoxic agents, which may have an important implication in predicting the response of patients with EOC to chemotherapy in the clinic.     

Absence of activating somatic mutations of PI3KCA and AKT1 genes in South Indian women with endometriosis

Objective

To investigate whether the PI3KCA and AKT1 gene influences the risk of developing endometriosis in South Indian women.

Study design

Mutations in exon 9 and 20 of PI3KCA gene and E17K mutation in exon 4 of AKT1 gene were tested for association in a case-control study between eutopic and ectopic endometrium tissue from 30 endometriosis cases and eutopic endometrium tissue from 30 controls. The genotype frequencies of these mutations were compared using polymerase chain reaction and direct sequencing analysis of tissue DNA.

Results

The analysis did not reveal any activating somatic mutations in either PI3KCA or AKT1 gene in the cases.

Conclusion

In the present study we could not observe any mutation in PI3KCA and AKT1 gene, indicating that these mutations are rarely associated with endometriosis in South Indian women.     

Outcomes of surgical management of bowel obstruction in relapsed epithelial ovarian cancer (EOC)

Objective

To describe the outcomes of surgical management of bowel obstruction in relapsed epithelial ovarian cancer (EOC) so as to define the criteria for patient selection for palliative surgery.

Methods

90 women with relapsed EOC underwent palliative surgery for bowel obstruction between 1992 and 2008.

Results

Median age at time of surgery for bowel obstruction was 57 years (range, 26 to 85 years). All patients had received at least one line of platinum-based chemotherapy. Median time from diagnosis of primary disease to documented bowel obstruction requiring surgery was 19.5 months (range, 29 days-14 years). Median interval from date of completed course of chemotherapy preceding surgery for bowel obstruction was 3.8 months (range, 5 days-14 years). Ascites was present in 38/90(42%). 49/90(54%) underwent emergency surgery for bowel obstruction. The operative mortality and morbidity rates were 18% and 27%, respectively. Successful palliation, defined as adequate oral intake at least 60 days postoperative, was achieved in 59/90(66%). Only the absence of ascites was identified as a predictor for successful palliation (p = 0.049). The median overall survival (OS) was 90.5 days (range, < 1 day-6 years). Optimal debulking, treatment-free interval (TFI) and elective versus emergency surgery did not predict survival or successful palliation from surgery for bowel obstruction (p > 0.05).

Conclusion

Surgery for bowel obstruction in relapsed EOC is associated with a high morbidity and mortality rate especially in emergency cases when compared to other gynaecological oncological procedures. Palliation can be achieved in almost two thirds of cases, is equally likely in elective and emergency cases but is less likely in those with ascites.     

RhoB mediates antitumor synergy of combined ixabepilone and sunitinib in human ovarian serous cancer

Objective

The aim was to evaluate antitumor activity of the combination of ixabepilone and sunitinib in pre-clinical models of chemotherapy naïve and refractory epithelial ovarian tumors, and to investigate the mechanism of synergy of such drug combination.

Methods

HOVTAX2 cell line was derived from a metastatic serous papillary epithelial ovarian tumor (EOC) and a paclitaxel-resistant derivative was established. Dose response curves for ixabepilone and sunitinib were generated and synergy was determined using combination indexes. The molecular mechanism of antitumor synergy was examined using shRNA silencing.

Results

The combination of ixabepilone and sunitinib demonstrated robust antitumor synergy in naïve and paclitaxel-resistant HOVTAX2 cell lines due to increased apoptosis. The GTPase, RhoB, was synergistically upregulated in cells treated with ixabepilone and sunitinib. Using shRNA, RhoB was demonstrated to mediate antitumor synergy. These results were validated in two other EOC cell lines.

Conclusions

Ixabepilone plus sunitinib demonstrated antitumor synergy via RhoB in naïve and paclitaxel-resistant cells resulting in apoptosis. This study demonstrates a novel mechanism of action leading to antitumor synergy and provides ‘proof-of-principle’ for combining molecular targeted agents with cytotoxic chemotherapy to improve antitumor efficacy. RhoB could be envisioned as an early biomarker of response to therapy in a planned Phase II clinical trial to assess the efficacy of ixabepilone combined with a receptor tyrosine kinase inhibitor such as sunitinib. To the best of our knowledge, this is the first demonstration of antitumor synergy between these two classes of drugs in EOC and the pivotal role of RhoB in this synergy.     

Prognosis of ovarian clear cell carcinoma compared to other histological subtypes: a meta-analysis

Objective

To compare the survival outcome between clear cell carcinoma (CCC) and other histological subtypes in epithelial ovarian carcinoma (EOC).

Methods

From January 1974 to February 2011, we identified a total of 31,800 (CCC; 2152, non-CCC; 29648) patients from 12 studies meeting the inclusion criteria.

Results

Heterogeneity tests demonstrated significant between-study variation (I² = 92.1%) with no significant difference in hazard ratio (HR) for death between CCC and non-CCC (HR; 1.16, 95% CI; 0.85-1.57, random-effects model). Comparing the HR based on stage I + II, and stage III + IV, between CCC and non-CCC, showed that CCC patients had a higher hazard rate for death than those with non-CCC of the ovary (stage I + II; HR; 1.17, 95% CI; 1.01-1.36, stage III + IV; HR; 1.65, 95% CI; 1.52-1.79). In a comparison of CCC and serous EOC, advanced stage (III and IV) CCC only showed a poorer hazard rate for death than serous EOC (HR; 1.71, 95% CI; 1.57-1.86).

Conclusion

This analysis suggests that ovarian CCC patients had poorer prognosis than those with other histological subtypes of EOC, especially in advanced EOC stages. Different treatment strategies may be needed for patients with ovarian CCC.     

Modulation of redox signaling promotes apoptosis in epithelial ovarian cancer cells

Objective

Epithelial ovarian cancer (EOC) cells are known to be resistant to apoptosis through a mechanism that may involve alteration in their redox balance. NADPH oxidase is a major source of intracellular superoxide, which is converted to the less toxic product by superoxide dismutase (SOD). Superoxide contributes to hypoxia inducible factor (HIF)-1α stabilization. We sought to determine the effects of inhibiting the generation of intracellular reactive oxygen species (ROS) on apoptosis of EOC cells.

Methods

Diphenyleneiodonium (DPI), an irreversible ROS inhibitor, was used to inhibit the generation of ROS in EOC cell lines, SKOV-3 and MDAH-2774, followed by assessment of apoptosis, NADPH oxidase, SOD3 and HIF-1α expression. A combination of immunohistochemistry, immunoprecipitation/western blot, and real-time RT-PCR were utilized to evaluate the expression of these enzymes in EOC cells as well as normal ovarian tissue and ovarian cancer tissue specimens.

Results

DPI treatment significantly induced apoptosis in both EOC cell lines as evident by increased caspase-3 activity and TUNEL assay. Additionally, both EOC cell lines were found to express NADPH oxidase, HIF-1α, and SOD3, which were highly sensitive to DPI treatment. DPI treatment resulted in reduced NADPH oxidase, SOD3 and HIF-1α levels. Furthermore, ovarian cancer tissues were found to manifest higher NADPH oxidase levels as compared to normal ovarian tissues.

Conclusions

These data suggest that lowering oxidative stress, possibly through the inhibition of NADPH oxidase, induces apoptosis in ovarian cancer cells and may serve as a potential target for cancer therapy.     

Characteristics of HPV prevalence among women in Liaoning province, China

Objectives

To investigate the prevalence rates of specific human papillomavirus (HPV) types infecting women in Liaoning Province, China.

Methods

Specimens from 4780 patients with cervical disease and 165 age-matched controls were tested for HPV genotypes using a chip hybridization assay.

Results

The infection rates were 35.66% for patients with cervicitis, 54.61% for those with ASCUS, 64.14% for those with CIN, 83.76% for those with cervical cancer in situ, and 83.12% for those with invasive cervical cancer. The most common HPV genotype was HPV-16, followed by HPV-58, HPV-52, HPV-33, HPV-53, and HPV-31. There were 1529 single and 731 multiple infections among the 4780 patients. Single infections with high-risk genotypes were associated with various cervical diseases. HPV-16 was present in 399 of the patients with multiple infections.

Conclusion

Compared with prevalence rates for other populations, the rates of specific HPV types infecting women are different in Liaoning Province of China.     

Tyrosine kinase A receptor (trkA): a potential marker in epithelial ovarian cancer

Objectives

To evaluate the role of trkA receptor as a potential tumor marker in serous epithelial ovarian cancer and its relationship with the angiogenic factors expression as vascular endothelial growth factor (VEGF) and nerve growth factor (NGF). Additionally, to examine whether NGF and VEGF secreted by epithelial ovarian cancer (EOC) explants and from epithelial ovarian cancer cell line (A2780) are involved in the process of angiogenesis, such as cellular proliferation, migration and differentiation of the human endothelial cell line (EA.hy926).

Methods

The mRNA levels of VEGF, NGF and trkA receptors were measured using PCR in 60 ovarian samples. Cellular localization and semi-quantitative estimation of VEGF, NGF, total trkA and p-trkA was performed using IHC in epithelial cells. NGF, total trkA and p-trkA protein were also evaluated in endothelial cells from the same tissues. Human endothelial cell line EA.hy926 was cultured with conditioned media obtained from both EOC explants and from the A2780 cell line, with or without NGF stimulus.

Results

Significantly higher levels of NGF, total trkA and p-trkA protein expressions were observed in epithelial and endothelial cells in poorly differentiated EOC versus normal ovary. Interestingly, the p-trkA receptor expression level showed the most significant difference and its presence was only found in borderline tumor and EOC samples indicating the importance of trkA receptor in EOC as a potential tumor marker.A significant increase in proliferation, migration and differentiation of EA.hy926 cells was observed with NGF, and this effect was significantly reverted when NGF was immuno-blocked and when a trkA inhibitor was used, showing that NGF is an important angiogenic factor in EOC by activating its trkA receptor.

Conclusion

These results indicate that p-trkA may be considered as a new potential tumor marker in EOC, and that NGF may also act as a direct angiogenic factor in EOC.     

A novel genome-based approach correlates TMPRSS3 overexpression in ovarian cancer with DNA hypomethylation

Objective

In an attempt to analyze more profoundly aberrant DNA hypomethylation in epithelial ovarian cancer (EOC), we applied a novel genome-based approach which includes expression profiling following pharmacologic stimulation of DNA methylation with the methyl donor S-adenosyl-l-methionine (SAM).

Methods

Four different EOC cell lines (OVCAR3, SKOV3, TOV21 and TOV112) were treated with SAM, and gene expression profiling was performed in SAM-treated and control EOC cells. Genes, downregulated upon SAM treatment were considered as potentially hypomethylated in EOC. DNA hypomethylation was independently validated in ovarian tumor and control tissues by bisulfite sequencing PCR (BSP).

Results

Among the genes identified, one of particular interest was the type II serine protease TMPRSS3 gene variants A and D (TMPRSS3-A/D), previously recognized as overexpressed in EOC and representing potential EOC therapeutic targets. Consecutive BSP analysis demonstrated that the common putative promoter region of the TMPRSS3-A/D gene variants was significantly hypomethylated in high-grade serous EOC tumors, compared to low-malignant potential ovarian tumors and normal ovarian tissue.

Conclusions

Our data imply that TMPRSS3-A/D overexpression in EOC is probably due to hypomethylation of their control region thus indicating that TMPRSS3-A/D variants could also represent novel molecular targets for epigenetic therapy of late stages of the disease. Our results also suggest that the frequently observed upregulation of different members of the type II serine proteases gene family in advanced cancer could be due to aberrant DNA hypomethylation. Furthermore, our study introduces a promising discovery approach that could be used for the identification of hypomethylated genes in different experimental cell models.     

Survival impact of capsule rupture in stage I clear cell carcinoma of the ovary in comparison with other histological types

Objective

We analyzed a large number of stage I clear cell carcinoma of the ovary (CCC) patients to estimate the survival impact of the capsule status in stage I CCC patients, particularly in comparison with non-CCC patients.

Methods

Clinicopathologic data on 564 patients with stage I epithelial ovarian cancer (EOC) collected under the central pathological review system were subjected to uni- and multivariable analyses to evaluate the disease-free survival (DFS) and overall survival (OS).

Results

There was no significant difference in both the OS and DFS of CCC patients between IA and IC(ir) (intraoperative capsule rupture) {IA vs. IC(ir); OS: P = 0.1402, DFS: P = 0.2701}. In contrast, CCC patients at IC(non-ir) {IC excluding for IC(ir), such as preoperative capsule rupture, positive ascites/washing, and surface involvement} showed a poorer OS and DFS than those at IC(ir), or those at the corresponding stage in non-CCC. In multivariable analysis, the capsule status was an independent prognostic factor of a poor OS and DFS {OS: HR, 2.832; 95% CI 1.156-6.938; P = 0.023; DFS: HR, 4.327; 95% CI, 1.937-9.667; P = 0.0004)} {In contrast, non-CCC: N.S. (OS/DFS)}. Furthermore, in CCC patients, intraperitoneal recurrences were more frequently observed in IC(non-ir) CCC than IA or IC(ir) CCC (P = 0.0083) {In contrast, non-CCC: N.S.}.

Conclusion

This study suggests that CCC patients other than those with intraoperative capsule rupture show a considerable risk for mortality despite adjuvant chemotherapy.     

MUC16 (CA125) regulates epithelial ovarian cancer cell growth, tumorigenesis and metastasis

Objectives

MUC16 (CA125) protein is a high molecular weight mucin overexpressed in the majority of epithelial ovarian cancers (EOC) but not in the epithelium of normal ovaries suggesting that it might play a role in EOC pathogenesis. Here, we explored the phenotypic consequences of MUC16 knockdown and expression of its C-terminal domain with the aim of establishing a role for MUC16 in tumorigenesis.

Methods

MUC16 was down-regulated by stably expressing an anti-MUC16 endoplasmic reticulum-targeted single-chain antibody which prevented MUC16 cell surface localization in NIH:OVCAR3 cells. In addition, we generated epitope tagged, N-terminal region-deleted MUC16 constructs with (MUC16TMU) and without (MUC16CTD) cytoplasmic tail deletions and stably expressed them in SKOV3 cells.

Results

Although MUC16 knockdown did not affect the cell growth rate, knockdown cells reached a stationary growth phase after 4 days whereas control cells continued to grow for up to 7 days. Colony formation assays in soft agar demonstrated that MUC16 knockdown cells had > 8-fold reduction in their ability to form colonies. Importantly, MUC16 knockdown completely prevents the formation of subcutaneous tumors in nude mice. Conversely, we show that ectopic expression of the MUC16CTD enhances SKOV3 tumor cell growth, colony formation in soft agar and enhances tumor growth and metastases in SCID mice. In addition, MUC16CTD expression increases cell motility, invasiveness, and metastatic property. Deletion of the cytoplasmic tail from the MUC16CTD completely abolished its ability to enhance tumor cell growth, cell motility and invasiveness. Furthermore, the increased invasive properties of MUC16CTD-expressing cells correlated with decreased expression of E-cadherin and increased expression of N-cadherin and vimentin.

Conclusion

These findings provide the first evidence for a critical role of MUC16 in tumor cell growth, tumorigenesis and metastases.     

Clear cell carcinoma of the ovary: a review of the literature

Objective

Different histologic types of epithelial ovarian cancer may represent different diseases with unique clinical and molecular characteristics. Clear cell carcinoma (CCC) of the ovary has been reported as having a worse prognosis than high grade serous epithelial ovarian cancer (EOC). This article critically reviews the literature pertinent to the pathology, pathogenesis, diagnosis, management, and outcome of patients with ovarian CCC.

Methods

MEDLINE was searched for all research articles published in English between January 01, 1977 and January 30, 2012 which reported on patients diagnosed with ovarian CCC. Given the rarity of this tumor, studies were not limited by design or number of reported patients.

Results

Ovarian CCC tumors represent 5-25% of ovarian cancers. Its histologic diagnosis can be challenging, resulting often times in misclassification of these tumors. Ovarian CCC tends to present at earlier stages and has been associated with endometriosis, ARID1A and PIK3CA mutations. When compared to stage-matched controls, patients with early-stage ovarian CCCs may have a better prognosis than patients with high-grade serous tumors. For those with advanced stage disease, high-grade serous histology confers a better prognosis than ovarian CCC. Patients with Stage IC-IV have a relatively poor prognosis and efforts should center in discovery of more effective treatment strategies.

Conclusions

Ovarian CCC is a biologically distinct entity, different from high-grade serous EOC. Future studies should explore the role of targeted therapies in the management of ovarian CCC.     

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy as upfront therapy for advanced epithelial ovarian cancer: multi-institutional phase-II trial

Objective.

The primary end-point of this multi-institutional phase-II trial was to assess results in terms of overall survival after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) in treatment-naive epithelial ovarian cancer (EOC) with advanced peritoneal involvement. Secondary end-points were treatment morbi-mortality and outcome effects of time to subsequent adjuvant systemic chemotherapy (TTC).

Methods.

Twenty-six women with stage III-IV EOC were prospectively enrolled in 4 Italian centers to undergo CRS and closed-abdomen HIPEC with cisplatin and doxorubicin. Then they received systemic chemotherapy with carboplatin (AUC 6) and paclitaxel (175 mg/m²) for 6 cycles.

Results.

Macroscopically complete cytoreduction was achieved in 15 patients; only minimal residual disease (≤ 2.5 mm) remained in 11. Major complications occurred in four patients and postoperative death in one. After a median follow-up of 25 months, 5-year overall survival was 60.7% and 5-year progression-free survival 15.2% (median 30 months). Excluding operative death, all the patients underwent systemic chemotherapy at a median of 46 days from combined treatment (range: 29-75). The median number of cycles per patient was 6 (range: 1-8). The time to chemotherapy did not affect the OS or PFS.

Conclusions.

In selected patients with advanced stage EOC, upfront CRS and HIPEC provided promising results in terms of outcome. Morbidity was comparable to aggressive cytoreduction without HIPEC. Postoperative recovery delayed the initiation of adjuvant systemic chemotherapy but not sufficiently to impact negatively on survival. These data warrant further evaluation in a randomized clinical trial.     

MicroRNA let-7a: a potential marker for selection of paclitaxel in ovarian cancer management

Objectives

Let-7 is a family of small non-coding RNAs regulating the expression of many genes that control important cellular activities. Let-7 is shown in vitro to sensitize cancer cells to platinum, but induce ovarian cancer resistance to paclitaxel. This study aims to investigate the effect of let-7a expression on survival outcomes of epithelial ovarian cancer (EOC) patients treated with different chemotherapy.

Methods

Let-7a expression was measured with qRT-PCR in ovarian tumors of 178 EOC patients who received platinum-based chemotherapy with and without paclitaxel after surgery. Survival analysis was performed to assess the effects of let-7a and chemotherapy on disease outcomes.

Results

Let-7a expression was detectable in the EOC samples, but the expression was not associated with disease stage, tumor grade, histology and debulking results. Patients who responded to platinum with paclitaxel had significantly lower let-7a than those who did not. Survival analyses showed that patients with high let-7a had better survival compared to those with low let-7a when they were treated with platinum without paclitaxel. The hazards ratios (HRs) for death and disease progression were 0.52 (95% CI: 0.29-0.96) and 0.48 (0.26-0.89) for high let-7a when compared to low let-7a, respectively. However, when patients were treated with platinum and paclitaxel, high let-7a was associated with worse progression-free and overall survival. The HRs for death and disease progression were 3.87 (95% CI: 1.28-11.66) and 3.48 (95% CI: 1.25-9.67) for high let-7a when compared to low let-7a, respectively. Further studies showed that among patients with low let-7a, those treated with paclitaxel in addition to platinum survived better than those treated without paclitaxel [adjusted-HRs were 0.31 (95% CI: 0.15-0.66) for death and 0.40 (95% CI: 0.22-0.75) for disease], while among those with high let-7a, the two types of treatment made no difference in patient survival.

Conclusions

The study suggests that the beneficial impact of the addition of paclitaxel on EOC survival was significantly linked to let-7a levels, and that miRNAs such as let-7a may be a useful marker for selection of chemotherapeutic agents in EOC management.