Breast Cancer Research Program

Research

Program Overview  

Breast cancer research has been a strong focus of the cancer center for 15 years. Population-based research by nationally recognized investigators in the Public Health Sciences Division has contributed greatly to our understanding of the risk factors associated with breast cancer development and pioneering work in bone marrow transplant for breast cancer has been essential for determining the appropriate patient group for such aggressive therapy. A formal Breast Cancer Research Program was initiated at Frede Hutch in 1995, when Dr. David Thomas received funds for four years from NCI to develop a multidisciplinary program to promote the translation of basic science findings into clinical advances. The development grant was used to successfully advance interdisciplinary research in breast cancer at the center. It provided funds for a total of 35 pilot projects grants that resulted in 27 manuscripts and external funding for 12 investigators.

The mission of the Breast Cancer Program is to develop a highly interdisciplinary group of investigators dedicated to reducing the incidence and subsequent mortality of breast cancer. The program fosters interdisciplinary research in basic science, genetics, clinical medicine, cancer prevention, and epidemiology at Fred Hutch, the faculty at the University of Washington, and the clinical community to improve breast cancer prevention, detection, diagnosis and treatment.

Researchers with major interests in Breast Program activities come from diverse backgrounds. Faculty are committed to developing and maintaining collaborative translational breast cancer research aims and they participate and present at monthly seminars to facilitate interactions. In addition, the program sponsors at least one workshop each year with a nationally-known breast cancer scientist as an invited speaker. The program also sponsors an evening seminar-dinner program for members and local physicians once a year. This facilitates communication of research activities to the clinical community, who generously allow access to their breast cancer patients and suggest new areas for clinical research.

Scientific Progress and Achievements

  

Genetics/Genomics

Kathleen Malone, with co-investigators Drs. Chu Chen and Janet Daling, Public Health Sciences, FHCRC, and Elaine Ostrander (now Branch Chief, Cancer Genetics, NIH/NHGRI) has led a case-control study of breast cancer in women ages 35 to 64, investigating the role of genetic susceptibility in the disease. This is an ancillary study to the multi-center NICHD Women's CARE Study of Caucasian and African-American women assessing the effects of alterations in a number of estrogen mediating/modulating genes, including CYP17, androgen receptor, CYP19, CYP1A1, CYP1B1, COMT, Vitamin D Receptor, HSD17B1, GST, and others, on breast cancer risk and on modification of the effects of selected exposures in 3,200 women. This study is also investigating mutations in BRCA1 and BRCA2 and will be one of the first population-based studies to directly assess these genes women outside the setting of family studies, high-risk clinics, and studies of early-onset breast cancer. Laboratory analyses for this project were recently completed and data analyses are underway.

Malone, Ostrander, and Daling continue to investigate the genetic contributions to breast cancer in young women within a population-based case-control study. Following up on the recent interest in the role of CHEK2 in breast cancer, they have recently completed an analysis of the risk of breast cancer in relation to several polymorphisms in the CHEK2 gene. [Friedrichson et al. 2004, in press, Breast Cancer Research]

Malone also participates in a multi-center study investigating genetic and radiation-related contributions to the risk of second primary breast cancer. The major focus of this project is on genes involved in the DNA repair pathway, including ATM, BRCA1/2, and others. A preliminary analysis was published this year regarding two ATM variants reported to relate to an increased risk of breast cancer. This study's replication attempt, using a much larger sample size, found these particular mutations not to be associated with an increased risk of second primary breast cancer [Bernstein et al., BJC 2003].

Ostrander, together with John Potter, Division Director, Public Health Sciences, FHCRC, and investigators at Johns Hopkins, has developed and published in PNAS the methodology for using evolutionary approaches to understand the role of missense changes in the BRCA2 gene in breast cancer susceptibility. This sets the stage for long-term studies on understanding the role of weakly penetrant mutations in cancer susceptibility.

Ostrander also collaborated with David Thomas on a study of BRCA1 and BRCA2 mutations in a large cohort of Shanghai women and found novel missense mutations in a subset of the women [Suter, et al., Cancer Epidemiol, Biomarkers and Prev, 2004].

Malone and Li Hsu, Biostatistics FHCRC, participate in a multi-center study investigating the validity of various statistical models currently used to assess BRCA1/2 mutation carrier probabilities. This collaborative project compared the predicted and observed results for a variety of study populations tested for BRCA1/2 mutations, including both high-risk clinic-based patient series and less selected population-based series. The first paper describing the differences across the models that were investigated has been submitted. [Parmigiani et al., under review, 2004]

Mary-Claire King continues her work to understand BRCA1 and BRCA2 and the genetics of breast and ovarian cancer. She has identified a complex germline rearrangement of BRCA1 that is associated with breast and ovarian cancer, and has worked with groups worldwide to map, clone and evaluate expression of critical genes in informative families and populations. Her lab identified a novel BRCA2 binding protein and reported on risk factors associated with inherited breast cancer in a population in New York [King et al., NEJM, 2004; King et al., Science, 2003]
 

Risk Factors and Tumor Markers of Prognosis

During the past nine years, Janet Daling has been the chair of the steering committee and principal investigator for one of five field sites for a large case-control study of breast cancer in women ages 35 to 64 (4,500+ cases, 4,500+ controls), i.e., the NICHD Women's CARE Study. The primary focus of this study is the role that contraceptive hormones and hormone replacement therapy may play in the development of breast cancer. The study is now complete, and numerous publications have been coauthored by Daling and Malone during the past year. In 2002, Daling and CARE investigators published a paper in Cancer showing that unopposed estrogen was not related to breast cancer risk among women under age 65; however, use of continuous combined hormone replacement therapy (HRT) substantially increased the risk of breast cancer, particularly that of lobular histology. A follow up paper assessing the histopathologic features of breast cancers in women from the CARE study according to use of various regimens of HRT reported that the tumors of women who have used HRT have better prognostic factors; however, for the most part, this advantage is likely due to the racial and age differences in those who use HRT and the effect of more frequent mammographic screening among HRT users [Daling et al., Cancer Epidemiol Biomarkers Prev. 2003]

A five-year case-control study of lobular and ductal breast cancer focusing on the relationship of combined hormone replacement therapy to lobular breast cancer led by Daling and in collaboration with Christopher Li, Malone and Peggy Porter continues in its fourth year. The Porter lab is evaluating molecular differences between lobular and ductal cancers in the study using genome-wide array assays of allelic loss and array CGH in research funded by the Department of Defense and NCI. Their findings that there are specific chromosomal regions associated with loss of estrogen receptor and with the lobular histological type will be published in Cancer Research in late 2004.

Daling's breast cancer study among women ages 65-79 (R01 CA 72787, "Calcium Channel Blockers in Breast Cancer Etiology", PI, Janet Daling) has been completed. Women in this age group were found to have no overall increased risk of breast cancer if they took calcium channel blockers, with the exception of women who used immediate release nondihydropyridines. These women had a significant 1.8-fold risk. A new finding in this study was the increased risk of breast cancer associated with diuretic use, a drug commonly used by women in this age group [Boudreau, et al., Cancer 2004]. Li received funding from the Avon Fund for innovative pilot project to conduct a study aimed at further understanding this relationship. In addition, several manuscripts based on this study were published over the last year, including assessments of the relationships between HRT, alcohol use, reproductive factors, and anthropometric factors and risks of invasive ductal and invasive lobular breast carcinomas. The data presented in these manuscripts suggest that beyond their histopathologic differences, ductal and lobular carcinomas appear to have different etiologies and different risk factors. For example, use of combined estrogen and progestin HRT and alcohol use appear to be more strongly related to risk of lobular carcinoma, while obesity appears to be more strongly related to risk of ductal carcinoma.

Daling, Li, Malone and Porter have initiated a study (R01 CA 97271, "Tamoxifen and Second Breast Cancer: Epidemiology and Pathology") to follow up on their initial finding of an increased risk of ER-negative contralateral tumors among women who were treated with tamoxifen. Malone, Daling and Porter also continue their research on the determinants of prognosis in women diagnosed with breast cancer before age 45 and have recently been funded to launch a large new cohort study examining predictors of survival in 2337 breast cancer patients diagnosed at ages 45-79.

Li if following up on findings from his recently published study on the role of c-erbB-2 in the etiology of contralateral breast cancer [Li, et al., Brit J Cancer 2003]. This work was done in collaboration with Daling, Malone, and Porter. In addition, he has continued his work on lobular breast carcinoma in collaboration with investigators at FHCRC and UW, investigating the changing incidence rates of lobular carcinoma and the relationship between different hormonal therapy regimens and risk of lobular carcinoma. This work resulted in two publications that received extensive national media coverage [Li, et al., JAMA 2003a; Li, et al., JAMA 2003b]. Finally, Li has also pursued his interest in examining differences in breast cancer outcomes by race/ethnicity. In a recently published report, he and his collaborators assessed differences in breast cancer stage, treatment, and survival among women in 17 different racial/ethnic groups, identifying important differences among groups that had not been previously studied.

With respect to future research directions, Li is leading an effort to study the relationship between use of the injectable contraceptive depot-medroxyprogesterone acetate (DMPA, Depo-Provera) and breast cancer risk. A handful of international studies have evaluated this association and suggest that women who are current DMPA users or who started using it at a young age have an elevated risk of breast cancer. However, a large-scale U.S.-based study is warranted, and Li and his colleagues have submitted a grant to NCI/NIH to fund such a study.

Peggy Porter continues to focus on identifying and understanding the molecular events associated with the initiation and progression of human cancer, particularly the role of abnormal cell proliferation and cell death. Defects in the pathways responsible for cell proliferation and death are likely to yield new markers for breast cancer detection and treatment. Analyses this year of data from a large population-based studies done in collaboration with colleagues at Emory University and James Roberts indicated that African American women are more likely to have breast cancers that are aggressive and that show aberrant expression of cell cycle regulators cyclin E, p16, p53 and cyclin D1. The differences observed in tumors of African American and white women, independent of stage and age at diagnosis, indicated that race might be a determinant, or surrogate for other determinants, of aggressive breast cancer and specific tumor cell cycle defects.

To further determine the clinical value of cell cycle abnormalities in breast cancer, Porter is collaborating with members of the Breast Committee of the Southwest Oncology Group (SWOG), including Robert Livingston and Stephanie Green, PhD, Public Health Sciences, to assess expression of cyclin E and p27 in tumors from a large randomized clinical trial. To rapidly test and evaluate immunohistochemical assays on the 3,000 tumors in the trial, Porter is constructing tissue microarrays (TMA) that contain 360 tissue cores each. The entire set of tumors from the clinical trial is represented in 18 master TMA blocks and slides from each master block are being assayed for expression of cyclin E and p27. This study will provide the first data concerning the association between cell cycle defects and response to therapy and survival in a randomized clinical trial.

Porter continues to collaborate with Hsu, Daling and Malone to evaluate genome-wide allelic loss in lobular and ductal type breast cancer using the new Affymetrix 10K SNP assay as part of an ongoing R01-funded project. Over the past year, Porter also collaborated with Jeff Delrow, PhD, FHRCR Genome Resource, Barbara Trask, PhD, Division Director, Human Biology, and Hsu to construct and test a human BAC array for CGH (Comparative Genome Hybridization). They have preliminarily tested over 40 breast tumors on the BAC array for gene copy changes throughout the genome and have identified specific chromosomal regions that are associated with loss of estrogen receptor or with specific histological tumor type. An R01 application has been submitted to investigate gene copy changes in breast tumors of African American and white women.

Early Detection and Screening

Emily White, Porter, and Constance Lehman are members of the Group Health Cooperative (GHC) "Breast Cancer Surveillance in a Defined Population" study (PI, Steve Taplin), a site in the NCI-sponsored Breast Cancer Surveillance Consortium. Through this collaboration and studies of the mammographically-screened population seen at GHC, reports concerning the relationship of breast density, tumor phenotype, and hormone replacement therapy use with mammographic efficacy have been published.

Constance Lehman's research interests and publications this year are focused on new methods and applications of breast MRI, including MR-guided biopsy, and on factors that influence the performance of mammography in early cancer detection. Since September 2002 and throughout this past year, Lehman has been working on studies to assess the clinical performance of breast MRI interpreted without, versus in conjunction with, computer aided diagnosis (CAD) through grants and partnerships with Confirma Corporation and through funding from the NCI. Lehman is currently serving as the PI on the American College of Radiology Imaging Network (ACRIN) study 6667: "MRI Screening of the Contralateral Breast in Women with a Recent Diagnosis of Breast Cancer". This is a definitive study to demonstrate the feasibility of using MRI to screen high-risk patients for breast cancer.

Future studies planned by Lehman include collaboration with William Perman, PhD, PI on the Department of Defense Congressionally Directed Medical Research Program grant: "Non-Invasive Detection and Characterization of Breast Neoplasms Using Sodium-23 Magnetic Resonance Mammography". This study will develop a highly sensitive and specific non-invasive technique for the detection and staging of breast tumors without the use of expensive contrast agents and, hopefully, provide a safe and effective means for the early detection of breast cancers.

Building on previous studies evaluating and the performance of mammography and on a previous collaboration developing innovative statistical methods for combining multiple biomarkers to maximize their performance, Nicole Urban is collaborating with laboratory investigators Kiviat, Disis and others to investigate whether a panel of biomarkers used in conjunction with current screening methods may improve early detection of all breast cancers, particularly aggressive cancers and those frequently missed by mammography. Markers under consideration include mammaglobin, lipid markers, and antibodies to oncogenic proteins. This study focuses on markers that can be measured in serum, and will include molecular profiling to identify aggressive subsets of breast cancer that are most in need of early detection. This 5-year study is funded by the DOD and includes collaborators from Cedars Sinai Medical Center and MD Anderson Cancer Center.

Mammography has been shown in several trials to decrease breast cancer mortality but its sensitivity is relatively poor in the young women with dense breasts who are typical of the high-risk population. In related work funded by the NCI/Avon collaboration, Urban collaborates with investigators at the four institutions with ovarian SPORE grants to investigate markers that may be useful in women at high risk for breast cancer. The goal of this two-year study is to use modern quantitative methods to identify and validate a panel of serum-based markers that can distinguish malignant from benign and normal breast conditions, to be used as an adjunct to mammography.
  

Prevention and Behavior Modification

Anne McTiernan and colleagues have published data this year showing that a moderate-intensity exercise intervention reduces serum estrogens and androgens in sedentary, overweight/obese postmenopausal women, with greater reduction in women who lost body fat. Additional publications show no effect of the exercise on estrogen metabolites; associations between gene polymorphisms, menstrual and reproductive factors, and serum hormones in postmenopausal women and breast cancer patients; and the role of the aromatase gene in exercise-induced weight loss in postmenopausal women. McTiernan and her colleagues have also published data from the HEAL cohort of breast cancer patients, showing an association between obesity and markers of breast cancer prognosis, decreases in physical activity levels after diagnosis, and the effect of physical activity on change in weight after diagnosis. In addition, she has been funded by NCI to conduct a 5-year trial comparing exercise vs weight loss in normal postmenopausal women on serum estrogens, androgens, mammogram density, and other breast cancer biomarkers, and by NCI Canada to be a center for a multi-center 7+-year clinical trial testing exemestane and celecoxib in breast cancer prevention. She submitted several projects for funding including: 1) a trial testing a Yoga intervention on immune function and stress in breast cancer patients; 2) a trial testing NSAIDs on mammogram density and other breast cancer biomarkers; and 3) a trial testing aerobic exercise effect on mammogram density and other breast cancer biomarkers in premenopausal women. She is leading the FHCRC response to an NCI RFA for a TREC Center focused on energy balance and cancer.

David Thomas continues research activities based on studies conducted on the cohort of women who were recruited into a randomized trial of breast self-examination in Shanghai between 1989 and 1991. All women in the cohort have been followed through 2000 for vital status, continued association with the Shanghai textile bureau, and the occurrence of any type of cancer. Thomas' main breast cancer-related research activity this year has been analysis of data from a study of nutrition, mammary cell proliferation, and breast cancer risk in Shanghai. Statistical analyses for four papers have been completed, and reports are currently being prepared. These papers will be based on information collected using a food frequency questionnaire. During the rest of this year, statistical analyses of data based on assays of serum and plasma from the women in the Shanghai study for selected nutrients will be completed. In collaboration with Dr. Chu Chen, assays for polymorphisms of genes responsible for hormone metabolism are being assessed. The aims of these studies are to identify nutritional and hormone-related risk factors for breast cancer, fibroadenoma of the breast, and proliferative changes in the non-cancerous mammary epithelium. In collaboration with Karen Rosenblatt, University of Illinois at Urbana-Champaign, data from the Shanghai cohort are being analyzed to investigate possible associations between risks of various cancers in relation to various contraceptive practices (oral, injectable, tubal ligation, IUD), induced and spontaneous abortions, childbearing factors and lactation. A paper on induced abortions and colon cancer has been provisionally accepted for publication.

As principal investigator of a program project under review by NCI, Deborah Bowen continues to research the effects of behavioral interventions on outcomes important to patients and family members. She, and colleagues from the UWMC and FHCRC, are beginning studies to test specific interventions in a large population of women with breast cancer and their families. The patient-specific interventions include exercise, diet and psychosocial and cognitive-behavioral outcomes to improve functioning after initial treatment. Bowen, McTiernan and Julie Gralow have also reported on factors that affect screening and genetic testing rates-data that can be used to design health policy.

In answer to the growing global impact of breast cancer and shared challenges among countries worldwide, Benjamin Anderson helped establish and chair a biennial program called "The Breast Health Global Initiative for Countries of Limited Resources: Consensus Guidelines for Early Detection, Diagnosis and Treatment" (originally titled the "Global Summit on International Breast Health"). The program aims to address breast healthcare measures in countries where access to healthcare is a challenge, where awareness is limited, and where cultural barriers need to be overcome. It is a collaboration among numerous partnering organizations and individuals who support the ongoing growth and development of international breast care guidelines, and who wish to promote communication in multiple areas, including dialogue around social barriers to women's health and breast cancer advocacy. The guidelines process advances systemic change for improved breast healthcare, as well as provides an essential instrument to elevate and standardize care. The first global summit of the Initiative took place in 2002 and resulted in publication of the first international breast healthcare guidelines for countries with limited healthcare resources in The Breast Journal in 2003. The second iteration of the guidelines was developed for publication at the second global summit January 12-15, 2005 in Bethesda, MD, in collaboration with the NCI Office of International Affairs. The Breast Health Global Initiative Global Summit on International Breast Health for Countries with Limited Resources is sponsored by the FHCRC and the Agency of Healthcare Research and Quality and co-sponsored by the Susan G. Komen Breast Cancer Foundation.
 

Treatment/Clinical Studies

The UW group of breast physicians is nationally recognized for breast cancer expertise and leadership in clinical trials research. Robert Livingston heads the solid tumor section at the SCCA and is the senior breast medical oncologist. He and Julie Gralow are Chair and Co-Chair, respectively, of the Southwest Oncology Group (SWOG) breast cancer committee. Through leadership in local investigator-initiated trials and national clinical trials, Livingston, Gralow, Georgiana Ellis, David Byrd, Constance Lehman, and David Mankoff actively develop, coordinate and accrue to clinical trials investigating interventions at all stages of the breast cancer continuum, including patients who are high-risk, early stage, metastatic, and long-term survivors. Examples of recent and ongoing clinical trials led by the UW breast cancer group include: 1) maximizing adjuvant doxorubicin-cyclophosphamide therapy through a continuous, "metronomic" dosing schedule, 2) optimizing schedule and dosing of anti-tubulin combination regimens for metastatic disease, with evaluation of biologic predictors of response, 3) defining the efficacy and sensitivity of sentinel lymph node mapping, 4) testing techniques for partial breast radiation, 5) studying the value of PET imaging for detecting breast cancer recurrences and monitoring response to therapy, 6) understanding the clinical value of magnetic resonance imaging (MRI) for breast imaging, 7) exploring state-of-the-art imaging techniques and biological factors as predictors of response to neoadjuvant chemotherapy regimens in early-stage disease, 8) evaluating the effect of phytoestrogens on normal breast tissue and menopausal symptoms in post-menopausal breast cancer survivors, and 9) studying the effect of exercise on osteoporosis, heart disease and quality of life in breast cancer survivors. Breast cancer treatment trials are frequently piloted within the University of Washington system and, if promising, taken to SWOG for testing and validation in the larger, multi-institution cooperative group setting.

The nuclear imaging Positron Emission Tomography (PET) Group at the UWMC was one of the first to focus on cancer imaging and as a longstanding NCI PO-1 (Kenneth Krohn, PhD, P.I.) to support research using PET to measure in vivo tumor biology. Mankoff continues his studies on the application of radiotracer imaging methods for breast cancer evaluation, focusing on both clinical questions related to staging and response monitoring and also translational questions related to factors affecting response and resistance of breast cancer to systemic therapy. His studies of locally advanced breast cancer (LABC) have identified a physiologic phenotype of tumors resistant to neo-adjuvant chemotherapy. Resistant tumors have unexpectedly high glucose metabolism, a high ratio of glucose metabolism per unit tumor blood flow, and persistent tumor blood flow with treatment. These factors predict poor response to chemotherapy, and in recent, they also predict poor disease-free and overall survival. These are the first data of their kind looking and in vivo tumor biology to infer mechanisms of resistance. Studies are underway (supported by a renewal of RO1 CA72064) to investigate the role of tumor hypoxia and response to therapy using PET hypoxia imaging and immunohistochemical approaches to measure hypoxia and its downstream effects. With resources from Avon pilot funding, and the FHCRC/UWMC Breast Specimen Repository, correlation of PET signatures with patterns of gene expression will be investigated.

Mankoff also continues to investigate PET estrogen receptor (ER) imaging as a method for selecting patients for hormonal therapy. Data were presented at the 2004 Society of Nuclear Medicine (SNM) meeting showing the level of uptake of the PET ER tracer, [F-18]-fluoroestradiol (FES), strongly predicts response to aromatase inhibitors in patients with recurrent or metastatic breast cancer. This work is supported by a longstanding. P01 grant in PET cancer imaging that supports PET ER imaging (CA42045, Krohn, PI). The group is working with NCI to forge approaches for further testing and clinical trials of this PET compound. UW is one of 5 sites desinated by NCI to carry early trials of imaging agents.

Mankoff also continues to investigate PET estrogen receptor (ER) imaging as a method for selecting patients for hormonal therapy. Data were presented at the 2004 Society of Nuclear Medicine (SNM) meeting showing the level of uptake of the PET ER tracer, [F-18]-fluoroestradiol (FES), strongly predicts response to aromatase inhibitors in patients with recurrent or metastatic breast cancer. This work is supported by a longstanding. P01 grant in PET cancer imaging that supports PET ER imaging (CA42045, Krohn, PI). The group is working with NCI to forge approaches for further testing and clinical trials of this PET compound. UW is one of 5 sites desinated by NCI to carry early trials of imaging agents.

Julie Gralow is PI on several local and national breast cancer clinical trials, and as co-chair of the Southwest Oncology Group Breast Cancer Committee (SWOG) she is involved in the development and direction of major trials within SWOG and the North American Breast Cancer Intergroup. A major area of personal research interest is anti-tubulin therapy. University of Washington pilots in metastatic breast cancer optimizing combined anti-tubulin therapy with vinca alkaloids and taxanes led to two ongoing phase II clinical trials in SWOG, S0102 and S0215, the former being chaired by Gralow. Biological factors predicting response to these anti-tubulin agents are being explored in both the local pilots and the SWOG trials, with a focus on Beta-tubulin isoforms and mutations. Understanding mechanisms of bone metastases continues to be a research focus. A major effort in the past year has included updating the American Society of Clinical Oncology Clinical Practice Guideline on bisphosphonates in breast cancer. Collaborations with the division of nuclear medicine are investigating FDG and [F-18]-fluoride PET compared to standard testing modalities for disease response evaluation in patients with bone-dominant metastatic breast cancer. A 6,000 patient SWOG/intergroup trial chaired by Gralow comparing three bisphosphonate agents in preventing bone metastasis in the adjuvant breast cancer setting, S0307, is in its final stages of development. Patient and tumor factors predicting the development of bone disease and benefit from bisphosphonate therapy will be explored in S0307. An investigation of potentially interesting bone metastasis biological correlates is ongoing using a University of Washington patient database. Other active studies chaired by Gralow include a phase III investigator-initiated multicenter trial of weekly docetaxel dosing in metastatic breast cancer, a multicenter phase II study of gemcitabine in combination with a new multi-targeted anti-folate (pemetrexed), a limited institution SWOG trial investigating barriers to accrual to clinical trials in the elderly, and a University of Washington/Fred Hutchinson trial of the effect of phytoestrogens on breast density and proliferation in breast cancer survivors.

Ellis and Livingston have conducted a series of UW pilots evaluating and optimizing a continuous, or "metronomic" regimen of adjuvant doxorubicin and cyclophosphamide (AC), using weekly doxorubicin, daily oral cyclophosphamide, and continuous filgrastim (G-CSF). Promising results in the Seattle pilots led to testing in SWOG S9625 as a neoadjuvant regimen in locally advanced breast cancer. A pathologic complete response rate of 25% (compared to 13% for the more conventional q3 weekly dosing schedule seen in two prior NSABP studies) generated sufficient enthusiasm to pursue further testing. SWOG S0012, led by Ellis, is currently comparing the conventional q3 weekly dosing of AC with the Seattle-generated continuous AC regimen (both followed by weekly paclitaxel) in a randomized phase III trial in a locally advanced population. The North American Intergroup will open SWOG S0221 this fall, a 5,000 patient phase III adjuvant study asking two questions: 1) how does the Seattle/SWOG continuous AC regimen compare to the new "dose-dense" q2 weekly AC dosing approach? And 2) how does weekly paclitaxel compare to the "dose-dense" q2 weekly paclitaxel schedule? Although the UW group and SWOG also have a strong interest in evaluating exciting new therapies in breast cancer, it is clear that optimizing dosing and schedules of "standard" breast cancer drugs may have significant impact on patient survival and toxicity.

Over the last year research by the Tumor Vaccine Group led by Nora Disis at the UWMC has focused on in vitro studies, evaluation of breast cancer-based immunotherapeutics in animal models, and the completion and initiation of several human clinical trials. This year, further long term follow-up of Disis' initial peptide-based vaccine studies (R01 CA7516) confirmed prolonged persistent immunity (>4 years) in evaluable patients and some indication of prolonged survival. Based on the conclusions of these trials, the Tumor Vaccine Group has launched 2 additional Phase II clinical trials that will address whether immunization against HER-2/neu in the setting of no evidence of disease can improve survival in patients with advance breast and ovarian cancer. Additionally, a Phase I clinical trial was initiated that will examine the safety and immunogenicity of a DNA vaccine targeting HER-2/neu. Pre-clinical animal studies demonstrated that DNA can be an effective vaccine approach by prolonging the duration of exposure of the immune system to tumor antigens. Disis has also initiated a phase I clinical trial of adoptive T cell therapy for the treatment of advanced malignancy in breast and ovarian cancer patients where vaccines may not be effective. In this trial, HER-2/neu-specific T cells will be expanded ex vivo and re-infused into patients. The Phase I clinical trial will address the feasibility and safety of this novel therapeutic strategy. Another Phase I clinical trial was also finalized and reported demonstrating that the dose of tumor antigen protein vaccine affects the time to the generation of a detectable immune response rather than the overall magnitude of the response. Several preclinical studies have been reported or are under way in the Tumor Vaccine Group. In a recent publication, Disis has shown that a disadvantage of targeting a single antigen is that immunoescape variants can arise as a result of the therapeutic strategy. To compensate for the evasive abilities of tumor, studies are also underway to identify additional breast and ovarian tumor antigens that can be formulated into multiantigen vaccines. Disis has recently joined in collaboration with other leaders in the field of vaccine development to begin preclinical analysis of peptide vaccines that target multiple breast and ovarian cancer associated antigens. Studies are underway in several other areas of immune-based approaches for the treatment and prevention of cancer. Preclinical studies are developing new adjuvant strategies to improve the immune response to tumor antigens by promoting mobilization and vaccine site infiltration of skin dendritic cell. Early studies by Disis and her colleagues are looking at how the tumor suppresses the immune response by recruiting regulatory T cells. Clinical trials are being planned to evaluate novel therapeutics to reduce the impact of tumor-induced immunosuppression.

Hannah Linden, a recent faculty addition to medical oncology, is working to define the role of the Androgen Receptor (AR) in breast cancer. She and Dr. Nick Agoff (Pathology, UWMC) published data this year regarding the favorable prognosis, and unexpectedly high prevalence of the AR in estrogen receptor negative breast cancer. A grant to the DOD to investigate steroid receptor associations in breast cancer has been funded and will proceed in collaboration with Mankoff and endocrinologists at the VAMC.

Linden has also partnered with the school of nursing to improve the supportive care of breast cancer patients, and their entry into clinical trials with two Susan Komen funded projects, including a "breast cancer buddy" program, and a research nurse on site at HMC. In collaboration with Dr. Debbie Ward (School of Nursing, UW), a separate proposal to the Komen Foundation has been submitted that will target patients with low medical literacy for extra assistance in navigating their breast related care.

The Cancer Genetics Clinic in the Medical Genetics Division of the UW assesses approximately 300 women annually for familial breast cancer risk. The Cancer Genetics Clinic receives referrals from the entire WAMI region and is the highest volume cancer genetics service in the Pacific Northwest. Women are seen by a genetic counselor and one of several medical geneticists with expertise in cancer genetics.

The Breast and Ovarian Cancer Prevention Program (BOCPP) is directed by Elizabeth Swisher and continues to expand its clinical activities and outreach efforts. The BOCPP is designed to serve women who have an elevated risk of breast and/or ovarian cancer and helps them formulate a tailored cancer prevention plan. The clinic meets monthly and involves a multi-disciplinary format that includes Swisher (gynecologic oncologist), Gralow, (oncologist), Robin Bennet (genetic counselor), Janet Abrams (psychologist) and Jean Stern (nutritionist). This year the BOCPP has increased its educational outreach efforts in the areas of recognition of increased cancer risk and cancer prevention to both medical providers and patients. Education on these topics has been provided to local providers attending continuing medical education seminars in women's health, breast cancer, and family medicine. BOCPP providers have traveled to outlying areas in Washington State to provide CME lectures. Next year, the BOCPP plans to expand physician education outreach to those areas in the WAMI region beyond Washington State. The BOCPP refers many patients to local and national clinical trials in prevention and screening. The BOCPP collaborated this year with Bonnie MacGregor (Psychology) and opened a prospective study for women undergoing prophylactic oophorectomy. This study will assess the impact of this surgery on quality of life and psychosocial functioning as well identifying predictors of poor outcome among women at high risk of breast and ovarian cancer.
 

Basic and Animal Model Studies

In 2003, James Roberts' lab had two major accomplishments that relate to breast cancer research. The first concerns new studies on telomerase, an enzyme that maintains chromosome ends (telomeres) by replacing the small amount of DNA that is lost each time the chromosome ends replicate. Normal cells contain a very low amount of telomerase and, consequently, can only duplicate a limited number of times before the loss of telomeric DNA triggers an irreversible block to further cell divisions. Cancer cells overcome this limitation by reactivating expression of telomerase, thereby stabilizing chromosome ends and bypassing the normal limit to their proliferative lifespan. In new work, Roberts' group has determined that maintenance of chromosome ends is not the only mechanism whereby telomerase contributes to cell proliferation. The expression of telomerase in human mammary epithelial cells is accompanied by changes in expression of a group of genes that directly stimulate cell division. These observations provide new insight into the oncogenic effects of telomerase, and may excite renewed interest in telomerase as a target for anti-tumor drug development.

The second significant accomplishment concerns new insights into the pathways that regulate the abundance of cyclin E, an important oncogene in human breast cancer. Autophosphorylation-triggered ubiquitination has been proposed as the major pathway regulating cyclin E protein abundance: phosphorylation of cyclin E on T380 by its associated CDK allows binding to the receptor subunit, Fbw7, of the multiprotein SCFFbw7 ubiquitin ligase. The Roberts' lab has tested this model in vivo and found it to be an inadequate representation of the pathways that regulate cyclin E degradation. They have shown that assembly of cyclin E into cyclin E-Cdk2 complexes is required in vivo for turnover by the Fbw7 pathway; that Cdk2 activity is required for cyclin E turnover in vivo because it phosphorylates S384; that phosphorylation of T380 in vivo does not require Cdk2, and is mediated primarily by GSK-3; and that two additional phosphorylation sites are also required for turnover, T62 and S372. Thus, cyclin E turnover is controlled by multiple biological inputs, and cannot be understood in terms of autophosphorylation alone.

The Roberts lab has made important progress on other research goals, in particular, in understanding the pathways that regulate the abundance of the tumor suppressor, p27Kip1. Mouse models now suggest that transcriptional mis-regulation of p27 may be much more important in tumorigenesis than previously thought. These transcriptional pathways have been identified and plans are underway to study their importance in human breast cancer. Progress in understanding the biological functions of p27 has also been made. New studies suggest that in addition to suppressing cell division, p27 may also enhance cell migration. Thus, p27 may have both tumor suppressor (anti-proliferative) and tumor promoting (pro-invasive) attributes, which may explain its complex regulation in human cancers.

Karen Swisshelm continues to investigate retinoid-mediated pathways that may suppress the tumor phenotype. As a model for gene therapy, she has performed xenograft studies in which the retinoic acid receptor beta 2 (RARb2) gene essentially prevented metastasis in a tumor resection model. As RARb2 is itself a transcription factor, she is currently investigating the down-stream targets of RARb2 regulatory pathways by expression mRNA profiling. Intriguingly, breast cancer cells produce a N-terminally truncated RARb protein isoform, RARb-prime (RARb'), that prevents retinoid activated gene transcription and normally differentiating functions from occurring in the cancer cells. Future focus will be to understand aberrant translational regulation in breast cancer. A collaboration with Peggy Porter is ongoing to validate biochemical studies in human breast cancer tissue specimens and to eventually translate these basic findings for future clinical studies.