Melanie Mackean

A role for methylation of the hMLH1 promoter in loss of hMLH1 expression and drug resistance in ovarian cancer

Experimental evidence from several sources has identified a link between mismatch repair deficiency and cytotoxic drug resistance. Selection for cisplatin resistance in the human ovarian cancer cell line A2780, results in loss of expression of the mismatch repair protein hMLH1 in most (90%) of the resultant cisplatin-resistant cell lines. Here we demonstrate that the cisplatin sensitive parental cell line displays methylation of the promoter of only one hMLH1 allele, but that the resistant cell lines all exhibit hyper-methylation of the promoters of both hMLH1 alleles. Full methylation of all sites tested was found to be invariably associated with loss of hMLH1 expression, whereas a partial increase in methylation appears compatible with either loss or maintenance of expression. In addition treatment of two of the resistant cell lines with 5-azacytidine, a known inhibitor of methylation, results in re-expression of hMLH1. Clonogenic assays demonstrate that the 5-azacytidine treated cells show increased sensitivity to cisplatin. Furthermore, 12.5% (3/24) of ovarian tumours show hypermethylation of the hMLH1 promoter. Expression of hMLH1 is absent in the tumours that are hypermethylated, while all the unmethylated tumours still express the protein. This analysis suggests that methylation of the hMLH1 promoter may be a common mechanism for loss of hMLH1 expression, and possibly for cisplatin-resistance, in ovarian cancer.

Antiestrogen Therapy Is Active in Selected Ovarian Cancer Cases: The Use of Letrozole in Estrogen Receptor–Positive Patients

Purpose: To evaluate the efficacy of the aromatase inhibitor letrozole in preselected estrogen receptor (ER)–positive relapsed epithelial ovarian cancer patients and to identify markers that predict endocrine-sensitive disease. Experimental Design: This was a phase II study of letrozole 2.5 mg daily until clinical or marker evidence of disease progression in previously treated ER-positive ovarian cancer patients with a rising CA125 that had progressed according to Rustins criteria. The primary end point was response according to CA125 and response evaluation criteria in solid tumors (RECIST) criteria. Marker expression was measured by semiquantitative immunohistochemistry in sections from the primary tumor. Results: Of 42 patients evaluable for CA125 response, 7 (17%) had a response (decrease of >50%), and 11 (26%) patients had not progressed (doubling of CA125) following 6 months on treatment. The median time taken to achieve the CA125 nadir was 13 weeks (range 10-36). Of 33 patients evaluable for radiological response, 3 (9%) had a partial remission, and 14 (42%) had stable disease at 12 weeks. Eleven patients (26%) had a PFS of >6 months. Subgroup analysis according to ER revealed CA125 response rates of 0% (immunoscore, 150-199), 12% (200-249), and 33% (250-300); P = 0.028, χ2 for trend. Expression levels of HER2, insulin-like growth factor binding protein 5, trefoil factor 1, and vimentin were associated with CA125 changes on treatment. Conclusions: This is the first study of a hormonal agent in a preselected group of ER-positive ovarian cancer patients. A signature of predictive markers, including low HER2 expression, predicts response.

Reduced MLH1 expression in breast tumors after primary chemotherapy predicts disease-free survival

PURPOSE Loss of function or expression of the mismatch repair protein MLH1 and the tumor suppressor protein p53 have been implicated in acquired resistance to anticancer drugs. We have compared the expression of MLH1 and p53 in tumors from women with clinically node-positive breast cancer before and after primary (neoadjuvant) chemotherapy. Further, we have assessed the value of these markers as predictors of response to therapy by correlation with disease-free survival. PATIENTS AND METHODS Immunohistochemistry scores of MLH1 and p53 expression were made on 36 tru-cut prechemotherapy biopsies and 29 paired postchemotherapy tumor samples. The significance of the change in scores and their correlation with disease-free survival were evaluated by the Wilcoxon signed rank sum test and Cox proportional hazards regression analysis, respectively. RESULTS Primary chemotherapy results in a significant reduction in the percent of cells expressing MLH1 (P =.010). This change in MLH1 expression after chemotherapy is strongly associated with poor disease-free survival (P =.0025). Expression of p53 was not significantly altered by chemotherapy. Neither MLH1 nor p53 expression before chemotherapy predicted disease-free survival or tumor response to chemotherapy. Low MLH1 expression after chemotherapy was an independent predictor of poor disease-free survival on multivariate Cox analysis when considered with other clinicopathologic prognostic factors. CONCLUSION Tumor cells that have reduced MLH1 expression seem to have a survival advantage during combined chemotherapy of locally advanced breast cancers, which supports the hypothesis that loss of MLH1 has a role in drug resistance. MLH1 expression after chemotherapy is an independent predictive factor for poor disease-free survival and may, therefore, define a group of patients with drug-resistant breast cancer.

A randomised, phase II trial of the DNA-hypomethylating agent 5-aza-2 '-deoxycytidine (decitabine) in combination with carboplatin vs carboplatin alone in patients with recurrent, partially platinum-sensitive ovarian cancer

Background:Our previous laboratory and clinical data suggested that one mechanism underlying the development of platinum resistance in ovarian cancer is the acquisition of DNA methylation. We therefore tested the hypothesis that the DNA hypomethylating agent 5-aza-2′-deoxycytodine (decitabine) can reverse resistance to carboplatin in women with relapsed ovarian cancer.Methods:Patients progressing 6–12 months after previous platinum therapy were randomised to decitabine on day 1 and carboplatin (AUC 6) on day 8, every 28 days or carboplatin alone. The primary objective was response rate in patients with methylated hMLH1 tumour DNA in plasma.Results:After a pre-defined interim analysis, the study closed due to lack of efficacy and poor treatment deliverability in 15 patients treated with the combination. Responses by GCIG criteria were 9 out of 14 vs 3 out of 15 and by RECIST were 6 out of 13 vs 1 out of 12 for carboplatin and carboplatin/decitabine, respectively. Grade 3/4 neutropenia was more common with the combination (60% vs 15.4%) as was G2/3 carboplatin hypersensitivity (47% vs 21%).Conclusions:With this schedule, the addition of decitabine appears to reduce rather than increase the efficacy of carboplatin in partially platinum-sensitive ovarian cancer and is difficult to deliver. Patient-selection strategies, different schedules and other demethylating agents should be considered in future combination studies.

Increased Incidence of Visceral Metastases in Scottish Patients With BRCA1/2-Defective Ovarian Cancer: An Extension of the Ovarian BRCAness Phenotype

PURPOSE To compare the frequency of visceral relapse of BRCA1/2-deficient ovarian cancer to that of nonhereditary controls. PATIENTS AND METHODS All patients diagnosed in Scotland with epithelial ovarian cancer (EOC) or primary peritoneal cancer (PPC) and a germline BRCA1/2 mutation were identified. Those with previous malignancy were excluded. Each remaining patient who experienced relapse was matched with two nonhereditary controls. RESULTS Seventy-nine patients with EOC/PPC and germline BRCA1/2 mutations were identified. Fifteen had inadequate clinical data, two had carcinosarcoma, 27 had previous breast cancer, and 16 were in remission. Of the remaining 19 patients who were BRCA1/2 deficient, 14 patients (74%) developed visceral metastases compared with six (16%) of 38 patients in the control group. The percentages of liver, lung, and splenic metastases were 53%, 32%, and 32%, respectively, in the patients compared with 5%, 3%, and 5%, respectively, in the controls. When events occurring outside the matched follow-up period were omitted, the percentages of visceral, liver, lung, and splenic metastases were 58%, 42%, 16%, and 32% in the patients compared with 5%, 0%, 0%, and 3% in controls (P < .001, P < .001, P = .066, and P = .011, respectively). In an independent validation set, the corresponding percentages of visceral, liver, lung, and splenic metastases were 63%, 46%, 13%, and 17% in the patients compared with 11%, 4%, 2%, and 2% in controls (P < .001, P < .001, P = .153, and P = .052, respectively). CONCLUSION Although sporadic EOC commonly remains confined to the peritoneum, BRCA1/2-deficient ovarian cancer frequently metastasizes to viscera. These data extend the ovarian BRCAness phenotype, imply BRCA1/2-deficient ovarian cancer is biologically distinct, and suggest that patients with visceral metastases should be considered for BRCA1/2 sequencing.

Improved Treatment and Survival for Lung Cancer Patients in South-East Scotland

Introduction: Lung cancer survival in Scotland has historically been poor but many changes to the lung cancer services have been introduced and this study was conducted to investigate the impact of these changes on treatment and survival. Methods: Data obtained from the Scottish Cancer Registry, South-East Scotland Cancer Network audit and Edinburgh Cancer Centre database were used to conduct a comparison of the management and outcomes of lung cancer patients from South-East Scotland diagnosed in 1995 and in 2002. Results: Data on 971 patients diagnosed in 2002 and 927 in 1995 were analyzed and demonstrated that though the use of treatment overall had not changed (62% in 2002 versus 63% in 1995) the use of potentially curative radiotherapy (15 versus 5% &khgr;2 p < 0.001) and chemotherapy for non-small cell lung cancer (18 versus 7% &khgr;2 p < 0.001) had increased, but not resection rates (11 versus 10%). The use of palliative radiotherapy declined (38% versus 31% &khgr;2 p < 0.001). Patients diagnosed in 2002 had an adjusted hazard of death of 0.7 (95% confidence interval, 0.6–0.8) compared with 1995, with median survival from date of diagnosis of 5.2 versus 4.1 month and 2 year overall survival 15 versus 11% (log rank p = 0.004). Localized disease and younger age were also associated with a reduced hazard of death. Conclusions: Patients diagnosed with lung cancer in Scotland in 2002 had a reduced hazard of death and improved survival compared with 1995. It is hypothesized that this was due in part to improvements in service organization and increased use of treatments likely to increase survival.

Complementary and alternative medicine use among women receiving chemotherapy for ovarian cancer in 2 patient populations.

Objective The authors evaluated attitudes toward complementary and alternative medicine (CAM) use in 2 populations of women receiving chemotherapy for epithelial ovarian cancer (EOC). Methods Women with EOC currently being treated with chemotherapy at 2 tertiary cancer centers, in Canada and the United Kingdom, completed a self-administered questionnaire on attitudes and perceptions of CAM and types of CAM used within the previous month. Results One hundred ninety-two patients (94 from Canada, 98 from United Kingdom) completed the questionnaire. Overall, 85 women (44%) were identified as CAM users. Complementary and alternative medicine use was more common among Canadian women (52%) compared with women from the United Kingdom (37%), P = 0.02. Participants used 71 different types of CAM, the majority (61%) taking multiple CAM. The frequency of CAM use was the same in primary compared with recurrent disease. Eighty-nine percent of CAM users considered it important for their oncologist to be aware of CAM use. Canadian women, however, were less likely to inform their physician (Canada: 50%; United Kingdom: 81%), P = 0.02. Motivations for CAM use were the same in both populations including assist healing (60%), boost the immune system (57%), improve quality of life (48%), and relieve symptoms (45%). Thirteen percent thought CAM could cure cancer, whereas 17% thought it would prevent recurrence. Conclusions Complementary and alternative medicine use is common in women receiving chemotherapy for EOC. Increasingly, interactions between CAM and prescribed medication are being identified. Oncologists should be aware and actively inquire about CAM use. Although patterns of CAM use differed, the motivation for starting CAM was similar, highlighting the need to address supportive care in all patients.

Higher incidence of isolated brain metastases in ovarian cancer patients with previous early breast cancer.

Background: The pathogenesis of brain metastasis as a relatively rare complication of epithelial ovarian cancer is poorly understood. Some observations suggest that brain metastases from ovarian cancer are becoming more common and that ovarian cancers, which metastasize to the brain, may have a different biological pattern. Methods: Data were extracted from the Edinburgh Ovarian Cancer Database on a cohort of patients managed at the Edinburgh Cancer Centre (UK) between 1998 and 2004. The incidence of brain metastases was compared between patients with previous treatment for early breast cancer and patients without previous treatment for early breast cancer. Baseline characteristics, the time to cancer antigen 125 relapse, the time to brain metastasis, and the radiological pattern of relapse were also compared between these patients. Results: We demonstrate a higher incidence of serous histology (P = 0.02) in patients in remission from early breast cancer and that the incidence of brain metastases in this group is 11.6% compared with 1.1% in patients without prior breast cancer (relative risk = 10.5, P < 0.001). Brain metastases were clinically evident after 45.6 months in patients with previous breast cancer compared with 21 months in patients without previous breast cancer (P = 0.008). Among the patients who developed brain metastases, isolated retroperitoneal lymph node recurrence was noticed in patients in remission from early breast cancer but rarely in other patients. Conclusions: Ovarian cancer patients with a history of early breast cancer have a higher incidence of brain metastases and a different pattern of disease recurrence. We speculate that a higher incidence of breast cancer early onset mutations in patients with previous early breast cancer underlies these observed differences.

Routine germline BRCA1 and BRCA2 testing in ovarian carcinoma patients: analysis of the Scottish real life experience

To determine the rates of germline BRCA1 and BRCA2 mutations in Scottish patients with ovarian cancer, before and after a change in testing policy.

Three Years of Erlotinib in Routine Practice for Non-small Cell Lung Cancer in South East Scotland

We present a review of 111 patients who were treated over an initial 3-year period with erlotinib. The median treatment time was 68 days and 59% of patients had stopped treatment within the first 3 months. However, 20 patients were on erlotinib for more than 12 months. Performance status and smoking history were the significant prognostic factors. The overall 3-year survival in patients who had never smoked was 26%.