Helen Mackay

Olaparib in patients with recurrent high-grade serous or poorly differentiated ovarian carcinoma or triple-negative breast cancer: a phase 2, multicentre, open-label, non-randomised study

BACKGROUND Olaparib (AZD2281) is a small-molecule, potent oral poly(ADP-ribose) polymerase (PARP) inhibitor. We aimed to assess the safety and tolerability of this drug in patients without BRCA1 or BRCA2 mutations with advanced triple-negative breast cancer or high-grade serous and/or undifferentiated ovarian cancer. METHODS In this phase 2, multicentre, open-label, non-randomised study, women with advanced high-grade serous and/or undifferentiated ovarian carcinoma or triple-negative breast cancer were enrolled and received olaparib 400 mg twice a day. Patients were stratified according to whether they had a BRCA1 or BRCA2 mutation or not. The primary endpoint was objective response rate by Response Evaluation Criteria In Solid Tumors (RECIST). All patients who received treatment were included in the analysis of toxic effects, and patients who had measurable lesions at baseline were included in the primary efficacy analysis. This trial is registered at ClinicalTrials.gov, number NCT00679783. FINDINGS 91 patients were enrolled (65 with ovarian cancer and 26 breast cancer) and 90 were treated between July 8, 2008, and Sept 24, 2009. In the ovarian cancer cohorts, 64 patients received treatment. 63 patients had target lesions and therefore were evaluable for objective response as per RECIST. In these patients, confirmed objective responses were seen in seven (41%; 95% CI 22-64) of 17 patients with BRCA1 or BRCA2 mutations and 11 (24%; 14-38) of 46 without mutations. No confirmed objective responses were reported in patients with breast cancer. The most common adverse events were fatigue (45 [70%] of patients with ovarian cancer, 13 [50%] of patients with breast cancer), nausea (42 [66%] and 16 [62%]), vomiting (25 [39%] and nine [35%]), and decreased appetite (23 [36%] and seven [27%]). INTERPRETATION Our study suggests that olaparib is a promising treatment for women with ovarian cancer and further assessment of the drug in clinical trials is needed. FUNDING AstraZeneca.

Targeting the protein kinase C family: are we there yet?

Protein kinase C (PKC) comprises a family of serine/threonine kinases that are involved in the transduction of signals for cell proliferation, differentiation, apoptosis and angiogenesis. Unsurprisingly, disruption of PKC regulation is implicated in tumorigenesis and drug resistance. PKC function is complex in this context owing to the differing roles of individual isozymes within the cell and across tumour types. Therapeutically targeting PKC isozymes is not new; however, with many of the early PKC inhibitor cytotoxic drug combinations being discarded at the phase II level, and recent phase III studies in non-small-cell lung cancer proving negative, whats going wrong?

Olaparib combined with chemotherapy for recurrent platinum-sensitive ovarian cancer: a randomised phase 2 trial.

BACKGROUND The poly(ADP-ribose) polymerase inhibitor olaparib has shown antitumour activity in patients with platinum-sensitive, recurrent, high-grade serous ovarian cancer with or without BRCA1 or BRCA2 mutations. The aim of this study was to assess the efficacy and tolerability of olaparib in combination with chemotherapy, followed by olaparib maintenance monotherapy, versus chemotherapy alone in patients with platinum-sensitive, recurrent, high-grade serous ovarian cancer. METHODS In this randomised, open-label, phase 2 study, adult patients with platinum-sensitive, recurrent, high-grade serous ovarian cancer who had received up to three previous courses of platinum-based chemotherapy and who were progression free for at least 6 months before randomisation received either olaparib (200 mg capsules twice daily, administered orally on days 1-10 of each 21-day cycle) plus paclitaxel (175 mg/m(2), administered intravenously on day 1) and carboplatin (area under the curve [AUC] 4 mg/mL per min, according to the Calvert formula, administered intravenously on day 1), then olaparib monotherapy (400 mg capsules twice daily, given continuously) until progression (the olaparib plus chemotherapy group), or paclitaxel (175 mg/m(2) on day 1) and carboplatin (AUC 6 mg/mL per min on day 1) then no further treatment (the chemotherapy alone group). Randomisation was done by an interactive voice response system, stratified by number of previous platinum-containing regimens received and time to disease progression after the previous platinum regimen. The primary endpoint was progression-free survival according to Response Evaluation Criteria in Solid Tumors version 1.1, analysed by intention to treat. Prespecified exploratory analyses included efficacy by BRCA mutation status, assessed retrospectively. This study is registered with ClinicalTrials.gov, number NCT01081951, and has been completed. FINDINGS Between Feb 12 and July 30, 2010, 173 patients at 43 investigational sites in 12 countries were enrolled into the study, of whom 162 were eligible and were randomly assigned to the two treatment groups (81 to the olaparib plus chemotherapy group and 81 to the chemotherapy alone group). Of these randomised patients, 156 were treated in the combination phase (81 in the olaparib plus chemotherapy group and 75 in the chemotherapy alone group) and 121 continued to the maintenance or no further treatment phase (66 in the olaparib plus chemotherapy group and 55 in the chemotherapy alone group). BRCA mutation status was known for 107 patients (either at baseline or determined retrospectively): 41 (38%) of 107 had a BRCA mutation (20 in the olaparib plus chemotherapy group and 21 in the chemotherapy alone group). Progression-free survival was significantly longer in the olaparib plus chemotherapy group (median 12.2 months [95% CI 9.7-15.0]) than in the chemotherapy alone group (median 9.6 months [95% CI 9.1-9.7) (HR 0.51 [95% CI 0.34-0.77]; p=0.0012), especially in patients with BRCA mutations (HR 0.21 [0.08-0.55]; p=0.0015). In the combination phase, adverse events that were reported at least 10% more frequently with olaparib plus chemotherapy than with chemotherapy alone were alopecia (60 [74%] of 81 vs 44 [59%] of 75), nausea (56 [69%] vs 43 [57%]), neutropenia (40 [49%] vs 29 [39%]), diarrhoea (34 [42%] vs 20 [27%]), headache (27 [33%] vs seven [9%]), peripheral neuropathy (25 [31%] vs 14 [19%]), and dyspepsia (21 [26%] vs 9 [12%]); most were of mild-to-moderate intensity. The most common grade 3 or higher adverse events during the combination phase were neutropenia (in 35 [43%] of 81 patients in the olaparib plus chemotherapy group vs 26 [35%] of 75 in the chemotherapy alone group) and anaemia (seven [9%] vs five [7%]). Serious adverse events were reported in 12 (15%) of 81 patients in the olaparib plus chemotherapy group and 16 of 75 (21%) patients in the chemotherapy alone group. INTERPRETATION Olaparib plus paclitaxel and carboplatin followed by maintenance monotherapy significantly improved progression-free survival versus paclitaxel plus carboplatin alone, with the greatest clinical benefit in BRCA-mutated patients, and had an acceptable and manageable tolerability profile. FUNDING AstraZeneca.

Phase II Study of Temsirolimus in Women With Recurrent or Metastatic Endometrial Cancer: A Trial of the NCIC Clinical Trials Group

PURPOSE Phosphatase and tensin homolog (PTEN) is a tumor suppressor gene, and loss of function mutations are common and appear to be important in the pathogenesis of endometrial carcinomas. Loss of PTEN causes deregulated phosphatidylinositol-3 kinase/serine-threonine kinase/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling which may provide neoplastic cells with a selective survival advantage by enhancing angiogenesis, protein translation, and cell cycle progression. Temsirolimus, an ester derivative of rapamycin that inhibits mTOR, was evaluated in this setting. PATIENTS AND METHODS Sequential phase II studies evaluated single-agent activity of temsirolimus in women with recurrent or metastatic chemotherapy-naive or chemotherapy-treated endometrial cancer. Temsirolimus 25 mg intravenously was administered weekly in 4-week cycles. RESULTS In the chemotherapy-naive group, 33 patients received a median of four cycles (range, one to 23 cycles). Of the 29 patients evaluable for response, four (14%) had an independently confirmed partial response and 20 (69%) had stable disease as best response, with a median duration of 5.1 months (range, 3.7 to 18.4 months) and 9.7 months (range, 2.1 to 14.6 months). Only five patients (18%) had progressive disease. In the chemotherapy-treated group, 27 patients received a median of three cycles (range, one to six cycles). Of the 25 patients evaluable for response, one (4%) had an independently confirmed partial response, and 12 patients (48%) had stable disease, with a median duration of 4.3 months (range, 3.6 to 4.9 months) and 3.7 months (range, 2.4 to 23.2 months). PTEN loss (immunohistochemistry and mutational analysis) and molecular markers of PI3K/Akt/mTOR pathway did not correlate with the clinical outcome. CONCLUSION mTOR inhibition with temsirolimus has encouraging single-agent activity in endometrial cancer which is higher in chemotherapy-naive patients than in chemotherapy-treated patients and is independent of PTEN status. The difference in activity according to prior therapy should be factored into future clinical trial designs.

Germline and somatic SMARCA4 mutations characterize small cell carcinoma of the ovary, hypercalcemic type

Small cell carcinoma of the ovary, hypercalcemic type (SCCOHT) is the most common undifferentiated ovarian malignancy in women under 40 years of age. We sequenced the exomes of six individuals from three families with SCCOHT. After discovering segregating deleterious germline mutations in SMARCA4 in all three families, we tested DNA from a fourth affected family, which also carried a segregating SMARCA4 germline mutation. All the familial tumors sequenced harbored either a somatic mutation or loss of the wild-type allele. Immunohistochemical analysis of these cases and additional familial and non-familial cases showed loss of SMARCA4 (BRG1) protein in 38 of 40 tumors overall. Sequencing of cases with available DNA identified at least one germline or somatic deleterious SMARCA4 mutation in 30 of 32 cases. Additionally, the SCCOHT cell line BIN-67 had biallelic deleterious mutations in SMARCA4. Our findings identify alterations in SMARCA4 as the major cause of SCCOHT, which could lead to improvements in genetic counseling and new treatment approaches.

Hormone-receptor expression and ovarian cancer survival: an Ovarian Tumor Tissue Analysis consortium study

BACKGROUND Few biomarkers of ovarian cancer prognosis have been established, partly because subtype-specific associations might be obscured in studies combining all histopathological subtypes. We examined whether tumour expression of the progesterone receptor (PR) and oestrogen receptor (ER) was associated with subtype-specific survival. METHODS 12 studies participating in the Ovarian Tumor Tissue Analysis consortium contributed tissue microarray sections and clinical data to our study. Participants included in our analysis had been diagnosed with invasive serous, mucinous, endometrioid, or clear-cell carcinomas of the ovary. For a patient to be eligible, tissue microarrays, clinical follow-up data, age at diagnosis, and tumour grade and stage had to be available. Clinical data were obtained from medical records, cancer registries, death certificates, pathology reports, and review of histological slides. PR and ER statuses were assessed by central immunohistochemistry analysis done by masked pathologists. PR and ER staining was defined as negative (<1% tumour cell nuclei), weak (1 to <50%), or strong (≥50%). Associations with disease-specific survival were assessed. FINDINGS 2933 women with invasive epithelial ovarian cancer were included: 1742 with high-grade serous carcinoma, 110 with low-grade serous carcinoma, 207 with mucinous carcinoma, 484 with endometrioid carcinoma, and 390 with clear-cell carcinoma. PR expression was associated with improved disease-specific survival in endometrioid carcinoma (log-rank p<0·0001) and high-grade serous carcinoma (log-rank p=0·0006), and ER expression was associated with improved disease-specific survival in endometrioid carcinoma (log-rank p<0·0001). We recorded no significant associations for mucinous, clear-cell, or low-grade serous carcinoma. Positive hormone-receptor expression (weak or strong staining for PR or ER, or both) was associated with significantly improved disease-specific survival in endometrioid carcinoma compared with negative hormone-receptor expression, independent of study site, age, stage, and grade (hazard ratio 0·33, 95% CI 0·21-0·51; p<0·0001). Strong PR expression was independently associated with improved disease-specific survival in high-grade serous carcinoma (0·71, 0·55-0·91; p=0·0080), but weak PR expression was not (1·02, 0·89-1·18; p=0·74). INTERPRETATION PR and ER are prognostic biomarkers for endometrioid and high-grade serous ovarian cancers. Clinical trials, stratified by subtype and biomarker status, are needed to establish whether hormone-receptor status predicts response to endocrine treatment, and whether it could guide personalised treatment for ovarian cancer. FUNDING Carraresi Foundation and others.

Clear cell carcinoma of the ovary: A report from the first Ovarian Clear Cell Symposium, June 24th, 2010

OBJECTIVES Recent literature has highlighted histological types of ovarian carcinoma as distinct diseases, each with unique clinical and molecular features. Historically, the diagnosis of ovarian clear cell carcinoma (CCC) has been of concern to both patients and physicians due to reports that CCC is associated with a worse prognosis than the more common serous type of ovarian carcinoma (HGSC). This review discusses the unique features of ovarian CCC. METHODS In June of 2010, a group of researchers and clinicians convened in Vancouver to review and discuss the clinical, pathological, molecular, and treatment-related features of CCC. RESULTS CCC is the second most common type of ovarian epithelial cancer, representing 5-25% of ovarian carcinomas. It is characterised by its association with endometriosis, and frequent mutations of ARID1A and PIK3CA. Low-stage CCC appears to have a better outcome than stage matched HGSC, while the opposite is true for high-stage disease, suggesting that the current standard treatments applied to HGSC are ineffective for CCC. CONCLUSIONS Ovarian CCC is highly distinct from HGSC, and a clearer understanding of the basic biology of this disease is needed. Alternative therapies should be explored: irradiation and targeting disease-specific molecular markers should be examined in greater detail. Finally, novel approaches to clinical trial design are needed due to the smaller numbers of patients affected.

Phase II trial of the histone deacetylase inhibitor belinostat in women with platinum resistant epithelial ovarian cancer and micropapillary (LMP) ovarian tumours

AIM Micropapillary/borderline (LMP) ovarian tumours are rarely included in clinical trials and are intrinsically resistant to radiation and chemotherapy. Platinum resistant epithelial ovarian cancer (EOC) has a poor prognosis. The histone deacetylase inhibitor belinostat demonstrated antitumour activity in pre-clinical ovarian cancer models. METHODS A phase II study was performed to evaluate the activity of belinostat in two patient populations: women with metastatic or recurrent platinum resistant (progression within 6 months) EOC and LMP ovarian tumours, both groups had received no more than 3 prior lines of chemotherapy. Belinostat 1000 mg/m(2)/d was administered iv days 1-5 of a 21 d cycle. Peripheral blood mononuclear cells (PBMCs) and tumour biopsies, where possible, for correlative studies were obtained prior to and following treatment. RESULTS Eighteen patients with EOC and 14 patients with LMP tumours were enrolled on study. Belinostat was well tolerated with no grade four toxicity (179 cycles). Grade 3 toxicity consisted of thrombosis (3 patients), hypersensitivity (1) and elevated ALP (1). One patient with LMP tumour had a partial response (unconfirmed) and 10 had stable disease (SD), 3 were non-evaluable. Median progression-free survival (PFS) was 13.4 months (95% confidence interval (CI), 5.6--not reached). Best response in patients with EOC was SD (nine patients) and median PFS was 2.3 months (95% CI, 1.2-5.7 months). An accumulation of acetylated histones H3 and H4 was noted in PBMCs and in tumour tissue. CONCLUSIONS Belinostat is well tolerated in both patient groups and shows some activity in patients with micropapillary (LMP) disease.

A Phase II Trial with Pharmacodynamic Endpoints of the Proteasome Inhibitor Bortezomib in Patients with Metastatic Colorectal Cancer

Purpose: To evaluate the effects of the proteasome inhibitor bortezomib on tumor growth in patients with advanced colorectal cancer, and to explore the relationship between correlative studies and clinical outcome. Design: Bortezomib (1.3 mg/m2) was administered i.v. on days 1, 4, 8, and 11 of a 21-day cycle. Tumor response was assessed after every two cycles. Tumor biopsies were done prior to treatment and on day 9 of the first treatment cycle. Biopsies were examined for Ser32/36-IκB, Ser276-nuclear factor κB (NFκB), hypoxia-inducible factor-1α (HIF-1α), carbonic anhydrase IX (CAIX), p53, and microvessel density using immunohistochemistry. Results: Nineteen patients received 42 cycles (range 1-4) of bortezomib. No objective response was seen; three patients had stable disease at cycle 2, two patients had progressive disease after cycle 1, and 11 patients had progressive disease at cycle 2. Of the three patients with stable disease, one had progressive disease after cycle 4, and two were withdrawn due to toxicity. The median time to progression was 5.1 weeks (95% confidence interval, 5.1-11.1 weeks). There was a significant increase in the expression of HIF-1α relative to its transcriptional target CAIX following bortezomib, and a similar effect was also observed in a companion study using a human tumor xenograft model. Expression of p53, Ser276-NFκB, and Ser32/36-IκB was unchanged. Conclusion: Single agent bortezomib is inactive in metastatic colorectal cancer. Using this regimen, there was no detectable effect on NFκB, but a significant accumulation of HIF-1α was seen relative to CAIX. This suggests that proteasome inhibition alters the response to tumor hypoxia, and further investigation of this effect is indicated.

Refining prognosis and identifying targetable pathways for high-risk endometrial cancer; a TransPORTEC initiative

This study aimed to investigate whether molecular analysis can be used to refine risk assessment, direct adjuvant therapy, and identify actionable alterations in high-risk endometrial cancer. TransPORTEC, an international consortium related to the PORTEC3 trial, was established for translational research in high-risk endometrial cancer. In this explorative study, routine molecular analyses were used to detect prognostic subgroups: p53 immunohistochemistry, microsatellite instability and POLE proofreading mutation. Furthermore, DNA was analyzed for hotspot mutations in 13 additional genes (BRAF, CDKNA2, CTNNB1, FBXW7, FGFR2, FGFR3, FOXL2, HRAS, KRAS, NRAS, PIK3CA, PPP2R1A, and PTEN) and protein expression of ER, PR, PTEN, and ARID1a was analyzed. Rates of distant metastasis, recurrence-free, and overall survival were calculated using the Kaplan–Meier method and log-rank test. In total, samples of 116 high-risk endometrial cancer patients were included: 86 endometrioid; 12 serous; and 18 clear cell. For endometrioid, serous, and clear cell cancers, 5-year recurrence-free survival rates were 68%, 27%, and 50% (P=0.014) and distant metastasis rates 23%, 64%, and 50% (P=0.001), respectively. Four prognostic subgroups were identified: (1) a group of p53-mutant tumors; (2) microsatellite instable tumors; (3) POLE proofreading-mutant tumors; and (4) a group with no specific molecular profile (NSMP). In group 3 (POLE-mutant; n=14) and group 2 (microsatellite instable; n=19) patients, no distant metastasis occurred, compared with 50% distant metastasis rate in group 1 (p53-mutant; n=36) and 39% in group 4 (NSMP; P<0.001). Five-year recurrence-free survival was 93% and 95% for group 3 (POLE-mutant) and group 2 (microsatellite instable) vs 42% (group 1, p53-mutant) and 52% (group 4, NSMP; P<0.001). Targetable FBXW7 and FGFR2 mutations (6%), alterations in the PI3K-AKT pathway (60%) and hormone receptor positivity (45%) were frequently found. In conclusion, molecular analysis of high-risk endometrial cancer identifies four distinct prognostic subgroups, with potential therapeutic implications. High frequencies of targetable alterations were identified and may serve as targets for individualized treatment.