Shulamith Rizel

D538G Mutation in Estrogen Receptor-α: A Novel Mechanism for Acquired Endocrine Resistance in Breast Cancer

Resistance to endocrine therapy occurs in virtually all patients with estrogen receptor α (ERα)-positive metastatic breast cancer, and is attributed to various mechanisms including loss of ERα expression, altered activity of coregulators, and cross-talk between the ERα and growth factor signaling pathways. To our knowledge, acquired mutations of the ERα have not been described as mediating endocrine resistance. Samples of 13 patients with metastatic breast cancer were analyzed for mutations in cancer-related genes. In five patients who developed resistance to hormonal therapy, a mutation of A to G at position 1,613 of ERα, resulting in a substitution of aspartic acid at position 538 to glycine (D538G), was identified in liver metastases. Importantly, the mutation was not detected in the primary tumors obtained prior to endocrine treatment. Structural modeling indicated that D538G substitution leads to a conformational change in the ligand-binding domain, which mimics the conformation of activated ligand-bound receptor and alters binding of tamoxifen. Indeed, experiments in breast cancer cells indicated constitutive, ligand-independent transcriptional activity of the D538G receptor, and overexpression of it enhanced proliferation and conferred resistance to tamoxifen. These data indicate a novel mechanism of acquired endocrine resistance in breast cancer. Further studies are needed to assess the frequency of D538G-ERα among patients with breast cancer and explore ways to inhibit its activity and restore endocrine sensitivity.

Doxorubicin-induced ovarian toxicity

BackgroundYoung cancer patients may occasionally face infertility and premature gonadal failure. Apart from its direct effect on follicles and oocytes, chemotherapy may induce ovarian toxicity via an impact on the entire ovary. The role of doxorubicin in potential ovarian failure remains obscure. Our intention was to elucidate doxorubicin-related toxicity within ovaries.MethodsFemale mice were injected intraperitoneally with 7.5 or 10 mg/kg doxorubicin and their ovaries were visualized in vivo by high resolution MRI, one day and one month following treatment. Ovaries of other treated mice were excised and weighed at the same post-treatment intervals. Ovarian histological sections were stained for TUNEL or active caspase-3 and follicles were counted and categorized. Ovulation rates were evaluated in superovulated female mice treated with doxorubicin.ResultsA single injection of doxorubicin resulted in a major reduction in both ovarian size and weight that lasted even one month post treatment. A dramatic reduction in ovulation rate was observed one week after treatment, followed by a partial recovery at one month. Histological examination revealed positive staining of TUNEL and active caspase-3. We observed a significant reduction in the population of secondary and primordial follicles one month following treatment.ConclusionsOur results may imply a mechanism of chemotherapy-induced ovarian toxicity, manifested by reduced ovulation and accompanied by a reduction in ovarian size, caused probably by an acute insult to the ovary.

Lapatinib or Trastuzumab Plus Taxane Therapy for Human Epidermal Growth Factor Receptor 2–Positive Advanced Breast Cancer: Final Results of NCIC CTG MA.31

PURPOSE The efficacy of lapatinib versus trastuzumab combined with taxanes in the first-line setting of human epidermal growth factor receptor 2 (HER2) -positive metastatic breast cancer (BC) is unknown. PATIENTS AND METHODS The MA.31 trial compared a combination of first-line anti-HER2 therapy (lapatinib or trastuzumab) and taxane therapy for 24 weeks, followed by the same anti-HER2 monotherapy until progression. Stratification was by prior (neo)adjuvant anti-HER2 therapy, prior (neo)adjuvant taxane, planned taxane, and liver metastases. The primary end point was intention-to-treat (ITT) progression-free survival (PFS), defined as time from random assignment to progression by RECIST (version 1.0) criteria, or death for patients with locally assessed HER2-positive tumors. The primary test statistic was a stratified log-rank test for noninferiority. PFS was also assessed for patients with centrally confirmed HER2-positive tumors. RESULTS From July 17, 2008, to December 1, 2011, 652 patients were accrued from 21 countries, resulting in 537 patients with centrally confirmed HER2-positive tumors. Median follow-up was 21.5 months. Median ITT PFS was 9.0 months with lapatinib and 11.3 months with trastuzumab. By ITT analysis, PFS was inferior for lapatinib compared with trastuzumab, with a stratified hazard ratio (HR) of 1.37 (95% CI, 1.13 to 1.65; P = .001). In patients with centrally confirmed HER2-positive tumors, median PFS was 9.1 months with lapatinib and 13.6 months with trastuzumab (HR, 1.48; 95% CI, 1.20 to 1.83; P < .001). More grade 3 or 4 diarrhea and rash were observed with lapatinib (P < .001). PFS results were supported by the secondary end point of overall survival, with an ITT HR of 1.28 (95% CI, 0.95 to 1.72; P = .11); in patients with centrally confirmed HER2-positive tumors, the HR was 1.47 (95% CI, 1.03 to 2.09; P = .03). CONCLUSION As first-line therapy for HER2-positive metastatic BC, lapatinib combined with taxane was associated with shorter PFS and more toxicity compared with trastuzumab combined with taxane.

The Role of Irradiation of the Internal Mammary Lymph Nodes in High-Risk Stage II to IIIA Breast Cancer Patients After High-Dose Chemotherapy: A Prospective Sequential Nonrandomized Study

PURPOSE This phase II single-institution prospective, nonrandomized trial investigates high-dose adjuvant chemotherapy and locoregional radiotherapy in patients with breast cancer. We compared the outcome of patients in this study treated with radiotherapy fields including the internal mammary nodes (IMN) to a group of patients who did not receive IMN irradiation. PATIENTS AND METHODS 100 patients with high-risk stage II-III breast cancer received doxorubicin-based adjuvant chemotherapy followed by high-dose chemotherapy, stem-cell support, and locoregional radiotherapy. The radiotherapy included electron-beam irradiation to the IMN. For 20 months during the study, no electron-beam facility was available and we were unable to deliver the IMN irradiation as planned to 33 patients. The remaining 67 patients (32 treated before and 35 treated after this period) received IMN irradiation. Patients with receptor-positive tumors received tamoxifen for 5 years. RESULTS At a median follow-up of 77 months for all of the patients, disease-free survival (DFS) was significantly prolonged in patients receiving IMN radiation compared to those without IMN radiation (73% v 52%; P =.02). A trend was seen for overall survival (OS; 78% v 64%; P =.08). Cox regression multivariate analysis found IMN radiotherapy to be significant both for DFS and OS. Estrogen receptor positivity was also significant for DFS. There was no treatment related mortality. CONCLUSION In patients with high-risk stage II to III breast cancer, the inclusion of the IMN in the radiotherapy field was associated with a statistically significant increase in DFS and a borderline increase in OS.

Chemotherapeutic and surgical induction of pathological complete remission and whole abdominal irradiation for consolidation does not enhance the cure of stage III ovarian carcinoma.

Thirty-eight patients with stage III ovarian carcinoma were treated with a protocol consisting of an initial phase of induction of remission with cyclophosphamide, hexamethylmelamine, doxorubicin, and cisplatin (CHAD) combination chemotherapy and a second laparotomy for resection of residual tumors, followed by a consolidation phase with curative doses of whole abdominal radiation. Six patients (16%) had stage IIIA disease, ten (26%) IIIB, and 22 (58%) had stage IIIC disease. All patients received three to 14 courses of CHAD chemotherapy with a clinical response rate (complete [CR] and partial [PR]) of 91%. Thirty-three patients underwent the second operation. In 14 patients no residual tumor was found, and in another 11 residual tumors found were totally resected. Thus, 25 of 33 (76%) were classified as in pathological complete remission (PCR) after this operation. Whole abdominal irradiation was well tolerated, although 12 of 29 (42%) of the irradiated patients required more than a 2-week interruption o...

Doxorubicin-induced apoptosis in germinal vesicle (GV) oocytes.

Ovarian failure is a-known side-effect observed in women treated for cancer. Doxorubicin (DXR) was found to be detrimental to MII mouse oocytes. We aimed at characterizing the effect of DXR on germinal vesicle (GV) oocytes that comprise the majority of oocytes within ovaries encountering chemotherapy. Mouse follicles and oocytes were exposed to DXR in vitro. DXR localization and its possible cellular targets were examined by fluorescence confocal microscopy. We demonstrated that DXR crosses the blood-follicle barrier and accumulates in oocytes and granulosa cells. The mechanism of DXR-induced apoptosis involves chromosomal disintegration, activation of the mitochondria followed by activation of PERK and caspase-12 and inactivation of PARP. The follicular GV oocytes were more vulnerable to the toxic effect of DXR than ovulated MII oocytes. We suggest that DXR elicits apoptotic signal within GV oocytes that involves activation of the mitochondria, induction of ER-stress and a possible increase in intracellular calcium.

Bisphosphonates in the Adjuvant Setting of Breast Cancer Therapy—Effect on Survival: A Systematic Review and Meta-Analysis

Background The role of bisphosphonates (BP) in early breast cancer (BC) has been considered controversial. We performed a meta-analysis of all randomized controlled trials (RCTs) that appraised the effects of BP on survival in early BC. Methods RCTs were identified by searching the Cochrane Library, MEDLINE databases and conference proceedings. Hazard ratios (HRs) of overall survival (OS), disease-free survival (DFS) and relative risks of adverse events were estimated and pooled. Results Thirteen trials met the inclusion criteria, evaluating a total of 15,762 patients. Meta-analysis of ten trials which reported OS revealed no statistically significant benefit in OS for BP (HR 0.89, 95% CI = 0.79 to 1.01). Meta-analysis of nine trials which reported the DFS revealed no benefit in DFS (HR 0.95 (0.81–1.12)). Meta-analysis upon menopausal status showed a statistically significant better DFS in the BP-treated patients (HR 0.81(0.69–0.95)). In meta-regression, chemotherapy was negatively associated with HR of survival. Conclusions Our meta-analysis indicates a positive effect for adjuvant BP on survival only in postmenopausal patients. Meta-regression demonstrated a negative association between chemotherapy use BP effect on survival. Further large scale RCTs are warranted to unravel the specific subgroups that would benefit from the addition of BP in the adjuvant setting.

Combined modality treatment for stage III ovarian carcinoma.

Thirty-eight Stage III ovarian carcinoma patients were treated with a combined modality protocol consisting of sequential initial surgery with a maximal tumor reduction, CHAD combination chemotherapy, second look reductive surgery and whole abdominal irradiation. Sixteen patients (42%) had minimal residual tumors (less than 2 cm) after initial surgery (Stage IIIA) and 22 (58%) had large residual tumors (greater than 2 cm) (Stage IIIB). The patients received 3-14 courses of CHAD combination chemotherapy, with a response rate (CR + PR) in the evaluable (Stage IIIB) patients of 91%. Twenty-eight patients had a second attempt of cytoreductive operation (10 Stage IIIA patients and 18 Stage IIIB patients). In 10 patients no residual tumor was found. In another 12 patients residual tumor (less than 2 cm) was found and completely resected, whereas in six patients a complete resection of large residual tumors (greater than 2 cm) was not possible. Twenty-one of the patients also completed a course of whole abdominal radiotherapy. Radiation was well-tolerated with the usual expected amounts of nausea, vomiting, diarrhea and transient leukopenia and thrombocytopenia. 11/21 (52%) of the patients relapsed within the first 18 months after completion of radiotherapy. The actuarial relapse-free survival at 36 months from completions of radiotherapy was 44%. The actuarial survival for the whole group from diagnosis was 43% at 3 years (70% for Stage IIIA and 41% for Stage IIIB). The data indicated that this combined modality protocol is both feasible and well-tolerated but its curative potential for patients with advanced ovarian carcinoma is as yet unknown.

Different schedules of granulocyte growth factor support for patients with breast cancer receiving adjuvant dose-dense chemotherapy: a prospective nonrandomized study.

PurposeThis prospective, nonrandomized study evaluates 4 schedules of granulocyte colony-stimulating factor (G-CSF) for patients with breast cancer receiving adjuvant dose-dense chemotherapy regarding febrile neutropenia, treatment delays, and costs. Patients and MethodsTwo hundred and thirty-one patients were enrolled to receive adjuvant dose-dense chemotherapy with 4 G-CSF schedules: filgrastim (300 mcg) days 3 to 10 [n = 84 (36.4%) group A]; days 3 to 7 [n = 26 (11.3%) group B]; days 5, 7, 9, and 11 [n = 64 (27.7%) group C], or pegfilgrastim (6 mg) on day 2 [n=57 (24.6%) group D]. ResultsThirteen patients were hospitalized due to 14 episodes of febrile neutropenia; 3 in group A, 3 in group B, 1 in group C, and 6 in group D. No statistically significant difference was observed among the 4 groups. Fewer febrile neutropenic events were observed in group C than in group D (P=0.041). No statistically significant differences were observed in treatment delays or other hematological toxicities. Average overall G-CSF cost per patient in groups A and D was

Abstract P5-08-02: Real-life analysis evaluating 1594 N0/Nmic breast cancer patients for whom treatment decisions incorporated the 21-gene recurrence score result: 5-year KM estimate for breast cancer specific survival with recurrence score results ≤30 is >98%

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