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2.
Int J Obes (Lond) ; 42(4): 711-720, 2018 04.
Article En | MEDLINE | ID: mdl-29104286

BACKGROUND/OBJECTIVES: Obesity (body mass index (BMI)⩾30 kg m-2) is associated with an increased risk of estrogen-dependent breast cancer after menopause. Levels of aromatase, the rate-limiting enzyme in estrogen biosynthesis, are elevated in breast tissue of obese women. Recently, the regulation of aromatase by the p53-hypoxia-inducible factor-1α (HIF1α)/pyruvate kinase M2 (PKM2) axis was characterized in adipose stromal cells (ASCs) of women with Li-Fraumeni Syndrome, a hereditary cancer syndrome that predisposes to estrogen-dependent breast cancer. The current study aimed to determine whether stimulation of aromatase by obesity-associated adipokine leptin involves the regulation of the p53-HIF1α/PKM2 axis. SUBJECTS/METHODS: Human breast ASCs were used to characterize the p53-HIF1α/PKM2-aromatase axis in response to leptin. The effect of pharmacological or genetic modulation of protein kinase C (PKC), mitogen-activated protein kinase (MAPK), p53, Aha1, Hsp90, HIF1α and PKM2 on aromatase promoter activity, expression and enzyme activity was examined. Semiquantitative immunofluorescence and confocal imaging were used to assess ASC-specific protein expression in formalin-fixed paraffin-embedded tissue sections of breast of women and mammary tissue of mice following a low-fat (LF) or high-fat (HF) diet for 17 weeks. RESULTS: Leptin-mediated induction of aromatase was dependent on PKC/MAPK signaling and the suppression of p53. This, in turn, was associated with an increase in Aha1 protein expression, activation of Hsp90 and the stabilization of HIF1α and PKM2, known stimulators of aromatase expression. Consistent with these findings, ASC-specific immunoreactivity for p53 was inversely associated with BMI in breast tissue, while HIF1α, PKM2 and aromatase were positively correlated with BMI. In mice, HF feeding was associated with significantly lower p53 ASC-specific immunoreactivity compared with LF feeding, while immunoreactivity for HIF1α, PKM2 and aromatase were significantly higher. CONCLUSIONS: Overall, findings demonstrate a novel mechanism for the obesity-associated increase in aromatase in ASCs of the breast and support the study of lifestyle interventions, including weight management, which may reduce breast cancer risk via effects on this pathway.


Aromatase/metabolism , Breast Neoplasms/metabolism , Leptin/metabolism , Obesity/metabolism , Tumor Suppressor Protein p53/metabolism , Adipocytes/metabolism , Animals , Aromatase/genetics , Body Mass Index , Breast/cytology , Breast/metabolism , Carrier Proteins/metabolism , Cells, Cultured , Female , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/metabolism , Mammary Glands, Animal/metabolism , Membrane Proteins/metabolism , Mice , Signal Transduction , Thyroid Hormones/metabolism , Thyroid Hormone-Binding Proteins
3.
Prostate Cancer Prostatic Dis ; 20(4): 418-423, 2017 12.
Article En | MEDLINE | ID: mdl-28653675

BACKGROUND: Obesity, a cause of subclinical inflammation, is associated with increased risk of high-grade prostate cancer (PC) and poor outcomes. Whether inflammation occurs in periprostatic white adipose tissue (WAT), and contributes to the negative impact of obesity on PC aggressiveness, is unknown. METHODS: In a single-center, cross-sectional design, men with newly diagnosed PC undergoing radical prostatectomy were eligible for study participation. The primary objective was to examine the prevalence of periprostatic WAT inflammation defined by the presence of crown-like structures (CLS-P) as detected by CD68 immunohistochemistry. Secondary objectives were to explore the clinical and systemic correlates of periprostatic WAT inflammation. Tumor characteristics and host factors including BMI, adipocyte diameter, and circulating levels of lipids, adipokines, and other metabolic factors were measured. Wilcoxon rank-sum, Chi-square, or Fisher's exact tests, and generalized linear regression were used to examine the association between WAT inflammation and tumor and host characteristics. RESULTS: Periprostatic fat was collected from 169 men (median age 62 years; median BMI 28.3). Periprostatic WAT inflammation was identified in 49.7% of patients and associated with higher BMI (P=0.02), larger adipocyte size (P=0.004) and Gleason grade groups IV/V tumors (P=0.02). The relationship between WAT inflammation and high Gleason grade remained significant after adjusting for BMI (P=0.04). WAT inflammation correlated with higher circulating levels of insulin, triglycerides, and leptin/adiponectin ratio, and lower high density lipoprotein cholesterol, compared to those without WAT inflammation (P's <0.05). CONCLUSION: Periprostatic WAT inflammation is common in this cohort of men with PC and is associated with high-grade PC.


Adipose Tissue, White/pathology , Inflammation/pathology , Obesity/pathology , Prostatic Neoplasms/pathology , Adipose Tissue, White/metabolism , Aged , Body Mass Index , Humans , Inflammation/complications , Inflammation/metabolism , Inflammation/surgery , Male , Middle Aged , Neoplasm Grading , Obesity/complications , Obesity/metabolism , Obesity/surgery , Prostate/metabolism , Prostate/pathology , Prostate/surgery , Prostatectomy , Prostatic Neoplasms/complications , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/surgery
4.
Breast Cancer Res Treat ; 161(2): 363-373, 2017 01.
Article En | MEDLINE | ID: mdl-27866278

PURPOSE: We examined acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) events among 9679 women treated for breast cancer on four adjuvant Alliance for Clinical Trials in Oncology trials with >90 months of follow-up in order to better characterize the risk for AML/MDS in older patients receiving anthracyclines. METHODS: We used multivariable Cox regression to examine factors associated with AML/MDS, adjusting for age (≥65 vs. <65 years; separately for ≥70 vs. <70 years), race/ethnicity, insurance, performance status, and anthracycline receipt. We also examined the effect of cyclophosphamide, the interaction of anthracycline and age, and outcomes for those developing AML/MDS. RESULTS: On Cancer and Leukemia Group B (CALGB) 40101, 49907, 9344, and 9741, 7290 received anthracyclines; 15% were in the age ≥65 and 7% were ≥70. Overall, 47 patients developed AML/MDS (30 AML [0.3%], 17 MDS [0.2%]); 83% of events occurred within 5 years of study registration. Among those age ≥65 and ≥70, 0.8 and 1.0% developed AML/MDS (vs. 0.4% for age <65), respectively. In adjusted analyses, older age and anthracycline receipt were significantly associated with AML/MDS (adjusted hazard ratio [HR] for age ≥65 [vs. <65] = 3.13, 95% confidence interval [CI] 1.18-8.33; HR for anthracycline receipt [vs. no anthracycline] = 5.16, 95% CI 1.47-18.19). There was no interaction between age and anthracycline use. Deaths occurred in 70% of those developing AML/MDS. CONCLUSIONS: We observed an increased risk for AML/MDS for older patients and those receiving anthracyclines, though these events were rare. Our results help inform discussions surrounding anticipated toxicities of adjuvant chemotherapy in older patients.


Breast Neoplasms/complications , Breast Neoplasms/epidemiology , Leukemia, Myeloid, Acute/epidemiology , Leukemia, Myeloid, Acute/etiology , Myelodysplastic Syndromes/epidemiology , Myelodysplastic Syndromes/etiology , Neoplasms, Second Primary , Age Factors , Aged , Aged, 80 and over , Anthracyclines/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Breast Neoplasms/drug therapy , Chemotherapy, Adjuvant/adverse effects , Cohort Studies , Female , Follow-Up Studies , Humans , Middle Aged , Risk , Time Factors
5.
Ann Oncol ; 28(2): 208-217, 2017 02 01.
Article En | MEDLINE | ID: mdl-27831505

New research questions emerge as medical needs continue to evolve and as we improve our understanding of cancer biology and treatment of malignancies. Although significant advances have been made in some areas of breast cancer research resulting in improvements in therapies and outcomes over the last few decades, other areas have not benefited to the same degree and we continue to have many gaps in our knowledge. This article summarizes the 12 short and medium-term clinical research needs in breast cancer deemed as priorities in 2016 by a panel of experts, in an attempt to focus and accelerate future research in the most needed areas: (i) de-escalate breast cancer therapies in early breast cancer without sacrificing outcomes; (ii) explore optimal adjuvant treatment durations; (iii) develop better tools and strategies to identify patients with genetic predisposition; (iv) improve care in young patients with breast cancer; (v) develop tools to speed up drug development in biomarker-defined populations; (vi) identify and validate targets that mediate resistance to chemotherapy, endocrine therapy and anti-HER2 therapies; (vii) evaluate the efficacy of local-regional treatments for metastatic disease; (viii) better define the optimal sequence of treatments in the metastatic setting; (ix) evaluate the clinical impact of intra-patient heterogeneity (intra-tumor, inter-tumor and inter-lesion heterogeneity); (x) better understand the biology and identify new targets in triple-negative breast cancer; (xi) better understand immune surveillance in breast cancer and further develop immunotherapies; and (xii) increase survivorship research efforts including supportive care and quality of life.


Breast Neoplasms/drug therapy , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Biomarkers, Tumor/metabolism , Biomedical Research , Breast Neoplasms/diagnosis , Breast Neoplasms/metabolism , Drug Resistance, Neoplasm , Female , Humans , Molecular Targeted Therapy , Quality Improvement , Treatment Outcome
6.
Breast Cancer Res Treat ; 158(1): 91-97, 2016 07.
Article En | MEDLINE | ID: mdl-27306421

We previously reported progression-free survival (PFS) results on a phase II trial of weekly paclitaxel, trastuzumab, and pertuzumab in patients with human epidermal growth factor receptor 2(HER2)-positive metastatic breast cancer (MBC) treated in the first- and second-line setting. Here, we report results for overall survival (OS) and updated PFS after an additional year of follow-up. Patients with HER2-positive MBC with 0-1 prior treatment were eligible. Treatment consisted of paclitaxel (80 mg/m(2)) weekly, and trastuzumab (loading dose 8 mg/kg â†’ 6 mg/kg) and pertuzumab (loading dose 840 mg â†’ 420 mg) every 3 weeks, all given intravenously. Primary endpoint was 6-month PFS. Secondary endpoints included median PFS, 6-month and median OS. Evaluable patients received at least one full dose of treatment. From January 2011 to December 2013, 69 patients were enrolled: 51 (74 %) and 18 (26 %) treated in first- and second-line metastatic settings, respectively. As of July 1, 2015, the median follow-up was 33 months (range 3-49 months; 67 patients were evaluable for efficacy). The median OS was 44 months (95 % CI 37.5-NR) overall and 44 months (95 % CI 38.3-NR) and 37.5 months (95 % CI 30.3-NR) for patients with 0 and 1 prior metastatic treatment, respectively; 6-month OS was 98 % (95 % CI 90-1). The 6-month PFS was 86 % (95 % CI 75-93) overall and 89 % (95 % CI 76-95) and 78 % (95 % CI 51-91) for patients with 0 and 1 prior therapy, respectively; and median PFS was 21.4 months (95 % CI 14.1-NR) overall and 25.7 months (95 % CI 14.1-NR) and 16.9 months (95 % CI 8.5-NR) for patients with 0-1 prior treatment, respectively. Treatment was well tolerated. Updated analysis demonstrates that weekly paclitaxel, when added to trastuzumab and pertuzumab, is associated with a favorable OS and PFS and offers an alternative to docetaxel-based therapy. http://www.ClinicalTrials.gov NCT0127604.


Antibodies, Monoclonal, Humanized/administration & dosage , Breast Neoplasms/drug therapy , Paclitaxel/administration & dosage , Receptor, ErbB-2/metabolism , Trastuzumab/administration & dosage , Administration, Intravenous , Adult , Aged , Aged, 80 and over , Antibodies, Monoclonal, Humanized/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/metabolism , Disease-Free Survival , Drug Administration Schedule , Female , Humans , Middle Aged , Paclitaxel/therapeutic use , Survival Analysis , Trastuzumab/therapeutic use , Treatment Outcome
7.
Br J Cancer ; 111(8): 1532-41, 2014 Oct 14.
Article En | MEDLINE | ID: mdl-25101563

BACKGROUND: In this study, we evaluated the ability of gene expression profiles to predict chemotherapy response and survival in triple-negative breast cancer (TNBC). METHODS: Gene expression and clinical-pathological data were evaluated in five independent cohorts, including three randomised clinical trials for a total of 1055 patients with TNBC, basal-like disease (BLBC) or both. Previously defined intrinsic molecular subtype and a proliferation signature were determined and tested. Each signature was tested using multivariable logistic regression models (for pCR (pathological complete response)) and Cox models (for survival). Within TNBC, interactions between each signature and the basal-like subtype (vs other subtypes) for predicting either pCR or survival were investigated. RESULTS: Within TNBC, all intrinsic subtypes were identified but BLBC predominated (55-81%). Significant associations between genomic signatures and response and survival after chemotherapy were only identified within BLBC and not within TNBC as a whole. In particular, high expression of a previously identified proliferation signature, or low expression of the luminal A signature, was found independently associated with pCR and improved survival following chemotherapy across different cohorts. Significant interaction tests were only obtained between each signature and the BLBC subtype for prediction of chemotherapy response or survival. CONCLUSIONS: The proliferation signature predicts response and improved survival after chemotherapy, but only within BLBC. This highlights the clinical implications of TNBC heterogeneity, and suggests that future clinical trials focused on this phenotypic subtype should consider stratifying patients as having BLBC or not.


Antineoplastic Agents/therapeutic use , Survival Analysis , Triple Negative Breast Neoplasms/drug therapy , Cohort Studies , Female , Humans , Middle Aged , Treatment Outcome , Triple Negative Breast Neoplasms/physiopathology
8.
Pharmacogenomics J ; 14(4): 336-42, 2014 Aug.
Article En | MEDLINE | ID: mdl-24513692

Peripheral neuropathy is a common dose-limiting toxicity for patients treated with paclitaxel. For most individuals, there are no known risk factors that predispose patients to the adverse event, and pathogenesis for paclitaxel-induced peripheral neuropathy is unknown. Determining whether there is a heritable component to paclitaxel-induced peripheral neuropathy would be valuable in guiding clinical decisions and may provide insight into treatment of and mechanisms for the toxicity. Using genotype and patient information from the paclitaxel arm of CALGB 40101 (Alliance), a phase III clinical trial evaluating adjuvant therapies for breast cancer in women, we estimated the variance in maximum grade and dose at first instance of sensory peripheral neuropathy. Our results suggest that paclitaxel-induced neuropathy has a heritable component, driven in part by genes involved in axon outgrowth. Disruption of axon outgrowth may be one of the mechanisms by which paclitaxel treatment results in sensory peripheral neuropathy in susceptible patients.


Antineoplastic Agents, Phytogenic/adverse effects , Axons/physiology , Breast Neoplasms/drug therapy , Multifactorial Inheritance , Paclitaxel/adverse effects , Peripheral Nervous System Diseases/chemically induced , Sensory Receptor Cells/drug effects , Breast Neoplasms/genetics , Female , Humans , Peripheral Nervous System Diseases/genetics , Polymorphism, Single Nucleotide
10.
Ann Oncol ; 25(3): 592-598, 2014 Mar.
Article En | MEDLINE | ID: mdl-24401928

BACKGROUND: Nonpegylated liposomal doxorubicin liposomal doxorubicin, (Myocet™; Sopherion Therapeutics, Inc Canada, and Cephalon, Europe) (NPLD; Myocet(®)) in combination with trastuzumabHerceptin(®) (Hoffmann-La Roche) has shown promising activity and cardiac safety. We conducted a randomized phase III trial of first-line NPLD plus trastuzumab and paclitaxel (Pharmachemie B.V.) (MTP) versus trastuzumab plus paclitaxel (TP) in patients with human epidermal growth factor 2 receptor (HER2)-positive metastatic breast cancer. PATIENTS AND METHODS: Patients were randomly assigned to NPLD (M, 50 mg/m(2) every 3 weeks for six cycles), trastuzumab (T, 4 mg/kg loading dose followed by 2 mg/kg weekly), and paclitaxel (P, 80 mg/m(2) weekly) or T + P at the same doses until progression or toxicity. The primary efficacy outcome was progression-free survival (PFS). RESULTS: One hundred and eighty-one patients were allocated to receive MTP, and 183 to TP. Median PFS was 16.1 and 14.5 months with MTP and TP, respectively [hazard ratio (HR) 0.84; two-sided P = 0.174]. In patients with estrogen receptor (ER)- and progesterone receptor (PR)-negative tumors, PFS was 20.7 and 14.0 months, respectively [HR 0.68; 95% confidence interval (CI) 0.47-0.99]. Median overall survival (OS) was 33.6 and 28.9 months with MTP and TP, respectively (HR 0.79; two-sided P = 0.083). In ER- and PR-negative tumors, OS was 38.2 and 27.9 months, respectively (HR 0.63; 95% CI 0.42-0.93). The frequency of adverse events was higher with MTP, but there was no significant difference in cardiac toxicity between treatment arms. CONCLUSION(S): The trial failed to demonstrate a significant clinical improvement with the addition of M to TP regimen. The clinical benefit observed in an exploratory analysis in the ER- and PR-negative population deserves consideration for further clinical trials. CLINICAL TRIAL NUMBER: NCT00294996.


Antibodies, Monoclonal, Humanized/therapeutic use , Breast Neoplasms/drug therapy , Doxorubicin/analogs & derivatives , Paclitaxel/therapeutic use , Receptor, ErbB-2/metabolism , Antibiotics, Antineoplastic/adverse effects , Antibiotics, Antineoplastic/therapeutic use , Antibodies, Monoclonal, Humanized/adverse effects , Antineoplastic Agents, Phytogenic/adverse effects , Antineoplastic Agents, Phytogenic/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Disease-Free Survival , Doxorubicin/adverse effects , Doxorubicin/therapeutic use , Drug Administration Schedule , Female , Humans , Neoplasm Metastasis/drug therapy , Paclitaxel/adverse effects , Polyethylene Glycols/adverse effects , Polyethylene Glycols/therapeutic use , Prospective Studies , Trastuzumab , Treatment Outcome
11.
Ann Oncol ; 23(12): 3075-3081, 2012 Dec.
Article En | MEDLINE | ID: mdl-22767584

BACKGROUND: Cyclophosphamide-methotrexate-5-fluorouracil (CMF) is often selected as adjuvant chemotherapy for older patients with early-stage breast cancer due to perceived superior tolerability. We sought to measure persistence with CMF, adherence to oral cyclophosphamide, and the association of these with toxic effects. PATIENTS AND METHODS: CALGB 49907 was a randomized trial comparing standard chemotherapy (CMF or AC, provider/patient choice) with capecitabine in patients aged ≥65 with stage I-IIIB breast cancer. Those randomized to standard therapy and choosing CMF were prescribed oral cyclophosphamide 100 mg/m(2) for 14 consecutive days in six 28-day cycles. Persistence was defined as being prescribed six cycles of at least one of the three CMF drugs. Adherence was the number of cyclophosphamide doses that women reported they had taken divided by the number prescribed. Persistence and adherence were based on case report forms and medication calendars. RESULTS: Of 317 randomized to standard chemotherapy, 133 received CMF. Median age was 73 (range 65-88). Seventy-one percent submitted at least one medication calendar; 65% persisted with CMF. Non-persistence was associated with node negativity (P = 0.019), febrile neutropenia (P = 0.002), and fatigue (P = 0.044). Average adherence was 97% during prescribed cycles. CONCLUSIONS: Self-reported adherence to cyclophosphamide was high, but persistence was lower, which may be attributable to toxic effects.


Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Medication Adherence , Patient Compliance , Age Factors , Aged , Aged, 80 and over , Capecitabine , Chemotherapy, Adjuvant/adverse effects , Cyclophosphamide/adverse effects , Cyclophosphamide/therapeutic use , Deoxycytidine/adverse effects , Deoxycytidine/analogs & derivatives , Deoxycytidine/therapeutic use , Female , Fluorouracil/adverse effects , Fluorouracil/analogs & derivatives , Fluorouracil/therapeutic use , Humans , Methotrexate/adverse effects , Methotrexate/therapeutic use
12.
Ann Oncol ; 22(12): 2575-2581, 2011 Dec.
Article En | MEDLINE | ID: mdl-21406471

BACKGROUND: SRC plays an important role in the pathogenesis of metastatic breast cancer (MBC). In preclinical models, paclitaxel and the oral SRC inhibitor dasatinib showed greater antitumor activity than either agent. To determine the maximum tolerated dose of this combination, we conducted a phase I study. PATIENTS AND METHODS: Patients with MBC; Eastern Cooperative Oncology Group performance status of zero to one; normal hepatic, renal and marrow function were eligible. Paclitaxel 80 mg/m(2) was given 3 weeks of 4. The starting dasatinib dose was 70 mg and was increased, using a standard 3 + 3 dose-escalation scheme. RESULTS: Fifteen patients enrolled (median age 54 years, range 35-74). No dose-limiting toxic effects (DLTs) occurred at dasatinib doses of 70-120 mg. One DLT (grade 3 fatigue) occurred in the dasatinib 150-mg cohort, which was expanded (six patients) with no further DLTs. However, due to cumulative toxic effects (rash, fatigue, diarrhea), the recommended phase II dose is dasatinib 120 mg. Of 13 assessable patients, a partial response was seen in 4 patients (31%), including 2 patients previously treated with taxanes; all received ≥120 mg dasatinib. An additional five patients (29%) had stable disease. CONCLUSION: In combination with weekly paclitaxel, the recommended phase II dose of dasatinib is 120 mg daily and preliminary activity has been seen in patients with MBC.


Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms, Male/drug therapy , Breast Neoplasms/drug therapy , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Breast Neoplasms/pathology , Breast Neoplasms, Male/pathology , Dasatinib , Edema/chemically induced , Female , Humans , Male , Middle Aged , Neoplasm Metastasis , Paclitaxel/administration & dosage , Pleural Effusion, Malignant/chemically induced , Pyrimidines/administration & dosage , Thiazoles/administration & dosage , Treatment Outcome
13.
Ann Oncol ; 22(12): 2597-2603, 2011 Dec.
Article En | MEDLINE | ID: mdl-21427063

BACKGROUND: Development of brain metastasis in patients with breast carcinoma correlates with poor outcome. Identification of tumor characteristics associated with breast cancer brain metastases (BCBM) could help identify patients at risk. PATIENTS AND METHODS: We studied 209 patients with BCBM. We evaluated a panel of proteins relevant to the biology of breast carcinoma on tissue microarrays of 133 primary tumors and 56 BCBM, including paired samples from 43 patients, and correlated the findings with the clinical outcome. RESULTS: The median survival after BCBM diagnosis was 19 months (95% confidence interval, 13-23 months). Patients presenting with solitary metastasis had a significantly longer median survival than those with multiple lesions (25 versus 11 months, P ≤ 0.0001). We found no significant discordance in the expression of tested markers, but identified a possible association between the expression of basal cytokeratin CK5/6 in the primary carcinoma and the development of multiple rather than solitary brain metastases. CONCLUSIONS: Expression of antigens commonly associated with breast carcinoma does not differ significantly between the primary tumor and the corresponding brain metastases. Although no specific immunoprofile identifies breast carcinomas that develop brain metastases, we observed a possible association between CK5/6 expression in the primary tumor and multiple versus solitary BCBM.


Biomarkers, Tumor/metabolism , Brain Neoplasms/secondary , Breast Neoplasms/pathology , Carcinoma/secondary , Tissue Array Analysis , Adult , Aged , Aged, 80 and over , Brain Neoplasms/metabolism , Brain Neoplasms/mortality , Breast Neoplasms/metabolism , Breast Neoplasms/mortality , Carcinoma/metabolism , Carcinoma/mortality , Disease-Free Survival , Female , Humans , Kaplan-Meier Estimate , Keratin-5/metabolism , Keratin-6/metabolism , Middle Aged
14.
Oncogene ; 29(3): 325-34, 2010 Jan 21.
Article En | MEDLINE | ID: mdl-19855434

The anti-HER2 antibody Trastuzumab (Herceptin) has been proven to be effective in the treatment of HER2-overexpressing breast cancer; resistance, however, invariably emerges in metastatic tumors. The expression of p95-HER2, a form of HER2 with a truncated extracellular domain that lacks the Trastuzumab binding epitope, has been implicated as a mechanism of resistance to the antibody. We utilized an in vivo tumor model that overexpresses p95-HER2 and showed it to be resistant to the signaling and antitumor effects of Trastuzumab. We find that both full-length and p95-HER2 interact with the HSP90 chaperone protein and are degraded in tumor cells exposed to HSP90 inhibitors in tissue culture and in vivo. Loss of expression of p95-HER2 is accompanied by downregulation of the phosphoinositide-3 kinase/AKT and extracellular signal-regulated kinase signaling pathways and inhibition of cell proliferation. Chronic administration of HSP90 inhibitors in vivo results in sustained loss of HER2 and p95-HER2 expression and inhibition of AKT activation, together with induction of apoptosis and complete inhibition of tumor growth in Trastuzumab-resistant, p95-HER2-overexpressing models. Thus, p95-HER2 is an HSP90 client protein, the expression and function of which can be effectively suppressed in vivo by HSP90 inhibitors. HSP90 inhibition is therefore a potentially effective therapeutic strategy for p95-HER2-mediated Trastuzumab-resistant breast cancer.


Antibodies, Monoclonal/pharmacology , HSP90 Heat-Shock Proteins/metabolism , Neoplasms/drug therapy , Receptor, ErbB-2/metabolism , 3T3 Cells , Animals , Antibodies, Monoclonal, Humanized , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Binding Sites/genetics , Cell Line, Tumor , Drug Resistance, Neoplasm , Female , HSP90 Heat-Shock Proteins/antagonists & inhibitors , HSP90 Heat-Shock Proteins/genetics , Heterocyclic Compounds, 4 or More Rings/pharmacology , Humans , Immunoblotting , Mice , Mice, Inbred BALB C , Mice, Nude , Mutation , Neoplasms/metabolism , Neoplasms/pathology , Phosphatidylinositol 3-Kinases/metabolism , Protein Binding , Proto-Oncogene Proteins c-akt/metabolism , Receptor, ErbB-2/genetics , Signal Transduction/drug effects , Trastuzumab , Tumor Burden/drug effects , Xenograft Model Antitumor Assays
15.
Curr Cancer Drug Targets ; 8(6): 522-32, 2008 Sep.
Article En | MEDLINE | ID: mdl-18781898

Hsp90 (heat shock protein 90) is a molecular chaperone that modulates the stability and/or transport of a diverse set of critical cellular regulatory, metabolism, organization, and signaling proteins. Binding to Hsp90 is required for normal function of many proteins. In addition, Hsp90 has an extra-cellular function. It is found in two isotypes: alpha which is inducible and beta which is constitutive. Tumor cells frequently over express Hsp90alpha, and Hsp90 is implicated in cancer progression. Hence Hsp90 has emerged as a potential target for cancer treatment. A variety of agents have been found to interfere with Hsp function, mainly by binding to an ATP binding site on the molecule. More recent agents interfere with protein binding or the dimerization of Hsp90 needed for function. Preclinical studies have demonstrated that disruption of the many client proteins chaperoned by Hsp90 is achievable and associated with significant growth inhibition, both in vitro and in tumor xenografts. As a result, agents which interfere with this protein's function are being tested in the clinic as a targeted method of interfering with malignant growth. We review the current clinical status of therapeutic efforts to perturb this pathway and discuss future directions.


HSP90 Heat-Shock Proteins/metabolism , Animals , HSP90 Heat-Shock Proteins/antagonists & inhibitors , HSP90 Heat-Shock Proteins/chemistry , Humans , Immunotherapy , Neoplasms/metabolism , Neoplasms/therapy , Protein Binding , Protein Conformation
16.
J Clin Oncol ; 19(11): 2771-7, 2001 Jun 01.
Article En | MEDLINE | ID: mdl-11387347

PURPOSE: The randomized study reported by Bezwoda et al of high-dose chemotherapy (HDC) for treatment of metastatic breast cancer was audited on site to verify the study results. Additional published studies were reviewed to determine whether they had been subject to the required institutional oversight. PATIENTS AND METHODS: Ninety patients were reported to have been randomized and treated on this trial. A log of the names, hospital numbers, entry dates, and regimen received had been provided by the principal investigator. A search of more than 15,000 sets of medical records available from two Johannesburg hospitals was performed to locate records for as many of these 90 patients as possible. Standard auditing techniques were used. Additional clinical trials published by Bezwoda were compared against the minutes of the University of the Witwatersrand Committee for Research on Human Subjects to verify review and approval. RESULTS: Records for only 61 of the 90 patients could be found. Of these 61, only 27 had sufficient records to verify eligibility for the trial by the published criteria. Of these 27, 18 did not meet one or more eligibility criteria. Only 25 patients appeared to have received their assigned therapy temporally associated with their enrollment date, and all but three of these 25 received HDC. The treatment details of individual patients were at great variance from the published data. Nine other trials reported by Bezwoda were not reviewed or approved by the appropriate institutional committee despite statements to the contrary in the publications. CONCLUSION: The multiple publications of this study do not report verifiable data, and nine other publications coauthored by the principal investigator contain at least one major untrue statement.


Antineoplastic Agents/therapeutic use , Breast Neoplasms/drug therapy , Fraud , Medical Audit , Randomized Controlled Trials as Topic/standards , Aged , Dose-Response Relationship, Drug , Female , Humans , Medical Records , Middle Aged , Randomized Controlled Trials as Topic/statistics & numerical data , Reproducibility of Results , Treatment Outcome
17.
J Clin Oncol ; 19(10): 2587-95, 2001 May 15.
Article En | MEDLINE | ID: mdl-11352950

PURPOSE: This phase II study evaluated weekly trastuzumab and paclitaxel therapy in women with HER2-normal and HER2-overexpressing metastatic breast cancer. Efficacy was correlated with immunohistochemical and fluorescent in situ hybridization (FISH) assay results. PATIENTS AND METHODS: Eligible patients had bidimensionally measurable metastatic breast cancer. Up to three prior chemotherapy regimens, including prior anthracycline and taxane therapy, were allowed. Trastuzumab 4 mg/kg and paclitaxel 90 mg/m2 were administered on week 1, with trastuzumab 2 mg/kg and paclitaxel 90 mg/m2 administered on subsequent weeks. HER2 status was evaluated using four different immunohistochemical assays and FISH. RESULTS: Patients received a median of 25 weekly infusions (range, one to 85 infusions). Median delivered paclitaxel dose-intensity was 82 mg/m2/wk (range, 52 to 90 mg/m2/wk). The intent-to-treat response rate for all 95 patients enrolled was 56.8% (95% confidence interval, 47% to 67%). A response rate of 61.4% (4.5% complete response, 56.8% partial response) was observed in 88 fully assessable patients. In patients with HER2-overexpressing tumors, overall response rates ranged from 67% to 81% compared with 41% to 46% in patients with HER2-normal expression (ranges reflect the different assay methods used to assess HER2 status). Differences in response rates between patients with HER2-overexpressing tumors and those with normal HER2 expression were statistically significant for all assay methods, with CB11 and TAB250 antibodies and FISH having the strongest significance. Therapy was generally well tolerated, although three patients had serious cardiac complications. CONCLUSION: Weekly trastuzumab and paclitaxel therapy is active in women with metastatic breast cancer. Therapy was relatively well tolerated; however, attention to cardiac function is necessary.


Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Genes, erbB-2/immunology , Adult , Aged , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal, Humanized , Breast Neoplasms/genetics , Breast Neoplasms/secondary , Drug Administration Schedule , Female , Gene Amplification , Humans , Immunophenotyping , In Situ Hybridization, Fluorescence , Middle Aged , Paclitaxel/administration & dosage , Trastuzumab , Treatment Outcome
18.
Proc Natl Acad Sci U S A ; 98(6): 3270-5, 2001 Mar 13.
Article En | MEDLINE | ID: mdl-11248068

The carbohydrate antigen globo H commonly found on breast cancer cells is a potential target for vaccine therapy. The objectives of this trial were to determine the toxicity and immunogenicity of three synthetic globo H-keyhole limpet hemocyanin conjugates plus the immunologic adjuvant QS-21. Twenty-seven metastatic breast cancer patients received five vaccinations each. The vaccine was well tolerated, and no definite differences were observed among the three formulations. Serologic analyses demonstrated the generation of IgM antibody titers in most patients, with minimal IgG antibody stimulation. There was significant binding of IgM antibodies to MCF-7 tumor cells in 16 patients, whereas IgG antibody reactivity was observed in a few patients. There was evidence of complement-dependent cytotoxicity in several patients. Affinity column purification supported the specificity of IgM antibodies for globo H. On the basis of these data, globo H will constitute one component of a polyvalent vaccine for evaluation in high-risk breast cancer patients.


Breast Neoplasms/therapy , Cancer Vaccines/therapeutic use , Vaccines, Conjugate/therapeutic use , Adult , Bone Neoplasms/secondary , Bone Neoplasms/therapy , Cancer Vaccines/adverse effects , Cancer Vaccines/immunology , Carbohydrate Sequence , Female , Humans , Immunization , Liver Neoplasms/secondary , Liver Neoplasms/therapy , Lung Neoplasms/secondary , Lung Neoplasms/therapy , Lymphatic Metastasis , Middle Aged , Molecular Sequence Data , Neoplasm Metastasis , Treatment Outcome , Vaccines, Conjugate/adverse effects , Vaccines, Conjugate/immunology
20.
Psychooncology ; 9(1): 44-56, 2000.
Article En | MEDLINE | ID: mdl-10668059

A single-arm pilot study explored the feasibility of adapting in Interpersonal Psychotherapy (IPT) by telephone to reduce psychological distress and to enhance coping during cancer treatment. Therapy focuses on role transitions, interpersonal conflicts, and grief precipitated by cancer. Breast cancer patients receiving high-dose chemotherapy received weekly sessions with a psychologist throughout chemotherapy and for 1 month afterwards. Patients could invite one 'partner' to receive individual telephone IPT. Psychosocial functioning was assessed using standardized measures at study entry, after chemotherapy, and following telephone IPT. Accrual and participation supplied evidence of feasibility: 14 patients and 10 partners were recruited, 82.5% of those eligible. Patients had a mean of 16 sessions; partners had a mean of 11. Participants rated their satisfaction with the program between 'good' and 'excellent'. A test of the efficacy of telephone IPT requires a larger, randomized trial. In order to standardize the intervention, a treatment manual was developed. This study indicated the importance of outreach to family members as well as to cancer patients, intensive patient education about oncology treatment and the medical care setting, and psychosocial services that continue after cancer treatment has been completed.


Breast Neoplasms/psychology , Couples Therapy , Psychotherapy , Telephone , Adaptation, Psychological , Adult , Caregivers/psychology , Feasibility Studies , Female , Grief , Humans , Middle Aged , Pilot Projects , Sick Role , Treatment Outcome
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