Eric A Ross

Fox Chase Cancer Center, Philadelphia, Pennsylvania, United States

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Publications (72)328.37 Total impact

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    ABSTRACT: New methods are needed to improve health behaviors, such as adherence to colorectal cancer (CRC) screening. Personalized genetic information to guide medical decisions is increasingly available. Whether such information motivates behavioral change is unknown.
    Annals of internal medicine 10/2014; 161(8):537-545. · 13.98 Impact Factor
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    ABSTRACT: Among Chinese immigrant populations, increasing duration of US residence is associated with elevated risk for various chronic diseases. Although life-style changes after migration have been extensively studied in immigrant populations, the psychosocial impact of acculturative stress on biological markers of health is less understood. Thus, the purpose of the present study is to examine associations between acculturative stress and inflammatory markers in a Chinese immigrant population.
    Psychosomatic medicine. 05/2014;
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    ABSTRACT: Neoadjuvant cisplatin-based chemotherapy is standard of care for muscle-invasive bladder cancer (MIBC); however, it is infrequently adopted in practice because of concerns regarding toxicity and delay to cystectomy. We hypothesized that three cycles of neoadjuvant accelerated methotrexate, vinblastine, doxorubicin, and cisplatin (AMVAC) would be safe, shorten the time to surgery, and yield similar pathologic complete response (pT0) rates compared with historical controls. Patients with cT2-T4a and N0-N1 MIBC were eligible and received three cycles of AMVAC with pegfilgrastim followed by radical cystectomy with lymph node dissection. The primary end point was pT0 rate. Telomere length (TL) and p53 mutation status were correlated with response and toxicity. Forty-four patients were accrued; 60% had stage III to IV disease; median age was 64 years. Forty patients were evaluable for response, with 15 (38%; 95% CI, 23% to 53%) showing pT0 at cystectomy, meeting the primary end point of the study. Another six patients (14%) were downstaged to non-muscle invasive disease. Most (82%) experienced only grade 1 to 2 treatment-related toxicities. There were no grade 3 or 4 renal toxicities and no treatment-related deaths. One patient developed metastases and thus did not undergo cystectomy; all others (n = 43) proceeded to cystectomy within 8 weeks after last chemotherapy administration. Median time from start of chemotherapy to cystectomy was 9.7 weeks. TL and p53 mutation did not predict response or toxicity. AMVAC is well tolerated and results in similar pT0 rates with 6 weeks of treatment compared with standard 12-week regimens. Further analysis is ongoing to ascertain whether molecular alterations in tumor samples can predict response to chemotherapy.
    Journal of Clinical Oncology 05/2014; · 18.04 Impact Factor
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    ABSTRACT: Patient participation in cancer clinical trials is low. Little is known about attitudinal barriers to participation, particularly among patients who may be offered a trial during an imminent initial oncology consult. The aims of the present study were to confirm the presence of proposed subscales of a recently developed cancer clinical trial attitudinal barriers measure, describe the most common cancer clinical trials attitudinal barriers, and evaluate socio-demographic, medical and financial factors associated with attitudinal barriers. A total of 1256 patients completed a survey assessing demographic factors, perceived financial burden, prior trial participation and attitudinal barriers to clinical trials participation. Results of a factor analysis did not confirm the presence of the proposed four attitudinal barriers subscale/factors. Rather, a single factor represented the best fit to the data. The most highly-rated barriers were fear of side-effects, worry about health insurance and efficacy concerns. Results suggested that less educated patients, patients with non-metastatic disease, patients with no previous oncology clinical trial participation, and patients reporting greater perceived financial burden from cancer care were associated with higher barriers. These patients may need extra attention in terms of decisional support. Overall, patients with fewer personal resources (education, financial issues) report more attitudinal barriers and should be targeted for additional decisional support.
    European Journal of Cancer Care 01/2014; · 1.31 Impact Factor
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    ABSTRACT: Objective This article describes the rigorous development process and initial feedback of the PRE-ACT (Preparatory Education About Clinical Trials) web-based- intervention designed to improve preparation for decision making in cancer clinical trials. Methods The multi-step process included stakeholder input, formative research, user testing and feedback. Diverse teams (researchers, advocates and developers) participated including content refinement, identification of actors, and development of video scripts. Patient feedback was provided in the final production period and through a vanguard group (N = 100) from the randomized trial. Results Patients/advocates confirmed barriers to cancer clinical trial participation, including lack of awareness and knowledge, fear of side effects, logistical concerns, and mistrust. Patients indicated they liked the tool's user-friendly nature, the organized and comprehensive presentation of the subject matter, and the clarity of the videos. Conclusion The development process serves as an example of operationalizing best practice approaches and highlights the value of a multi-disciplinary team to develop a theory-based, sophisticated tool that patients found useful in their decision making process. Practice Implications. Best practice approaches can be addressed and are important to ensure evidence-based tools that are of value to patients and supports the usefulness of a process map in the development of e-health tools.
    Patient Education and Counseling 01/2014; · 2.60 Impact Factor
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    ABSTRACT: This study used the Ottawa Decision Support Framework to evaluate a model examining associations between clinical trial knowledge, attitudinal barriers to participating in clinical trials, clinical trial self-efficacy, and clinical trial preparedness among 1256 cancer patients seen for their first outpatient consultation at a cancer center. As an exploratory aim, moderator effects for gender, race/ethnicity, education, and metastatic status on associations in the model were evaluated. . Patients completed measures of cancer clinical trial knowledge, attitudinal barriers, self-efficacy, and preparedness. Structural equation modeling (SEM) was conducted to evaluate whether self-efficacy mediated the association between knowledge and barriers with preparedness. . The SEM explained 26% of the variance in cancer clinical trial preparedness. Self-efficacy mediated the associations between attitudinal barriers and preparedness, but self-efficacy did not mediate the knowledge-preparedness relationship. . Findings partially support the Ottawa Decision Support Framework and suggest that assessing patients' level of self-efficacy may be just as important as evaluating their knowledge and attitudes about cancer clinical trials.
    Medical Decision Making 11/2013; · 2.89 Impact Factor
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    ABSTRACT: Caring for a relative or friend with cancer may be highly demanding and emotionally burdensome. Theory suggests that personal characteristics of a caregiver may contribute directly to a caregiver's emotional health. An underexplored variable is a caregiver's perception of choice in providing care to a relative or friend. Thus, this study sought to characterize perceived choice in providing care among family cancer caregivers and examine its association with emotional stress. This study is a secondary analysis of cross-sectional telephone interviews of 1,247 family caregivers, which included 104 cancer caregivers. The findings indicated that a high majority of cancer caregivers expressed elevated emotional stress. Most caregivers perceived themselves to have had a choice in providing care; however, a perceived lack of choice in providing care was significantly associated with greater emotional stress. Assessing clinical and policy-related strategies for alleviating concerns related to choice may be of value in the cancer context.
    Western Journal of Nursing Research 11/2013; · 1.22 Impact Factor
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    ABSTRACT: Purpose: For cancer patients offered clinical trials, treatment decisions may be especially complex as trials pose uncertain risks and benefits of new approaches. Many patients also have financial concerns, including those regarding insurance coverage. We hypothesize that financial concerns may affect a patient’s ability to make an informed, patient-centered decisions regarding clinical trials. Method: PRE-ACT (PReparatory Education About Clinical Trials) is a web-based educational tool designed to increase cancer patients’ preparation for making decisions about clinical trial enrollment by delivering video content tailored to individuals’ knowledge gaps and attitudes assessed by baseline survey. We conducted a multicenter, randomized study of PRE-ACT vs. written generic clinical trials information. The baseline survey (5-point Likert scales) included questions regarding cost concerns: “How much of a burden on you is the cost of your medical care? (Q1)”, “I'm afraid that my health insurance won't pay for a clinical trial (Q2),” and “I’m worried that I wouldn’t be able to afford the costs of treatment on a clinical trial (Q3).” We summed results, with higher scores indicating greater financial concerns. Multiple linear regression was used to measure the association between concerns and self-reported measures of self-efficacy, preparation for decision making, distress and decisional conflict in separate models, controlling for sociodemographic characteristics. In secondary analyses, similar models were built using the cost questions (Q2 and 3) together and burden (Q1) alone. Result: 1212 patients completed baseline surveys. 27% were 65 or older. 58% were female. 24% had high school education or less. Greater financial concern was associated with lower self-efficacy and preparation for decision making, and greater decisional conflict and distress, even after adjustment for age, race, gender, education, employment and hospital location (p<.0001 for all models). In the self-efficacy, preparation and distress models, age < 65, unemployment and lack of education past high school were also significantly associated with greater concerns (p<.05 for all models) . Similar findings were noted for secondary analyses, except that greater burden (Q3) was not associated with worse self-efficacy. Conclusion: Financial concerns are associated with several psychological constructs that may negatively impact informed decision-making regarding clinical trial participation. Greater attention to patients’ financial needs and available resources may best help them make optimal treatment decisions that reflect their preferences and values.
    The 35th Annual Meeting of the Society for Medical Decision Making; 10/2013
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    ABSTRACT: In an effort to standardize behavioral measures and their data representation, the present study develops a methodology for incorporating measures found in the National Cancer Institute's (NCI) grid-enabled measures (GEM) portal, a repository for behavioral and social measures, into the cancer data standards registry and repository (caDSR). The methodology consists of four parts for curating GEM measures into the caDSR: (1) develop unified modeling language (UML) models for behavioral measures; (2) create common data elements (CDE) for UML components; (3) bind CDE with concepts from the NCI thesaurus; and (4) register CDE in the caDSR. UML models have been developed for four GEM measures, which have been registered in the caDSR as CDE. New behavioral concepts related to these measures have been created and incorporated into the NCI thesaurus. Best practices for representing measures using UML models have been utilized in the practice (eg, caDSR). One dataset based on a GEM-curated measure is available for use by other systems and users connected to the grid. Behavioral and population science data can be standardized by using and extending current standards. A new branch of CDE for behavioral science was developed for the caDSR. It expands the caDSR domain coverage beyond the clinical and biological areas. In addition, missing terms and concepts specific to the behavioral measures addressed in this paper were added to the NCI thesaurus. A methodology was developed and refined for curation of behavioral and population science data.
    Journal of the American Medical Informatics Association 09/2013; · 3.57 Impact Factor
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    ABSTRACT: BACKGROUND: Cancer patients and their oncologists often report differing perceptions of consultation discussions and discordant expectations regarding treatment outcomes. CONNECT, a computer-based communication aid, was developed to improve communication between patients and oncologists. METHODS: CONNECT includes assessment of patient values, goals, and communication preferences; patient communication skills training; and a preconsultation physician summary report. CONNECT was tested in a 3-arm, prospective, randomized clinical trial. Prior to the initial medical oncology consultation, adult patients with advanced cancer were randomized to the following arms: 1) control; 2) CONNECT with physician summary; or 3) CONNECT without physician summary. Outcomes were assessed with postconsultation surveys. RESULTS: Of 743 patients randomized, 629 completed postconsultation surveys. Patients in the intervention arms (versus control) felt that the CONNECT program made treatment decisions easier to reach (P = .003) and helped them to be more satisfied with these decisions (P < .001). In addition, patients in the intervention arms reported higher levels of satisfaction with physician communication format (P = .026) and discussion regarding support services (P = .029) and quality of life concerns (P = .042). The physician summary did not impact outcomes. Patients with higher levels of education and poorer physical functioning experienced greater benefit from CONNECT. CONCLUSIONS: This prospective randomized clinical trial demonstrates that computer-based communication skills training can positively affect patient satisfaction with communication and decision-making. Measurable patient characteristics may be used to identify subgroups most likely to benefit from an intervention such as CONNECT. Cancer 2013. © 2013 American Cancer Society.
    Cancer 01/2013; · 5.20 Impact Factor
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    ABSTRACT: PURPOSEAlthough no specific delay threshold after diagnosis of breast cancer has been demonstrated to affect outcome, delays can cause anxiety, and surgical waiting time has been suggested as a quality measure. This study was performed to determine the interval from presentation to surgery in Medicare patients with nonmetastatic invasive breast cancer who did not receive neoadjuvant chemotherapy and factors associated with a longer time to surgery. METHODS Medicare claims linked to Surveillance, Epidemiology, and End Results data were reviewed for factors associated with delay between the first physician claim for a breast problem and first therapeutic surgery.ResultsBetween 1992 and 2005, 72,586 Medicare patients with breast cancer had a median interval (delay) between first physician visit and surgery of 29 days, increasing from 21 days in 1992 to 32 days in 2005. Women (29 days v 24 days for men; P < .001), younger patients (29 days; P < .001), blacks and Hispanics (each 37 days; P < .001), patients in the northeast (33 days; P < .001), and patients in large metropolitan areas (32 days; P < .001) had longer delays. Patients having breast conservation and mastectomies had adjusted median delays of 28 and 30 days, respectively, with simultaneous reconstruction adding 12 days. Preoperative components, including imaging modalities, biopsy type, and clinician visits, were also each associated with a specific additional delay. CONCLUSION Waiting times for breast cancer surgery have increased in Medicare patients, and measurable delays are associated with demographics and preoperative evaluation components. If such increases continue, periodic assessment may be required to rule out detrimental effects on outcomes.
    Journal of Clinical Oncology 11/2012; · 18.04 Impact Factor
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    ABSTRACT: BACKGROUND: It is accepted that a woman's lifetime risk of developing breast cancer after menopause is reduced by early full term pregnancy and multiparity. This phenomenon is thought to be associated with the development and differentiation of the breast during pregnancy. METHODS: In order to understand the underlying molecular mechanisms of pregnancy induced breast cancer protection, we profiled and compared the transcriptomes of normal breast tissue biopsies from 71 parous (P) and 42 nulliparous (NP) healthy postmenopausal women using Affymetrix Human Genome U133 Plus 2.0 arrays. To validate the results, we performed real time PCR and immunohistochemistry. RESULTS: We identified 305 differentially expressed probesets (208 distinct genes). Of these, 267 probesets were up- and 38 down-regulated in parous breast samples; bioinformatics analysis using gene ontology enrichment revealed that up-regulated genes in the parous breast represented biological processes involving differentiation and development, anchoring of epithelial cells to the basement membrane, hemidesmosome and cell-substrate junction assembly, mRNA and RNA metabolic processes and RNA splicing machinery. The down-regulated genes represented biological processes that comprised cell proliferation, regulation of IGF-like growth factor receptor signaling, somatic stem cell maintenance, muscle cell differentiation and apoptosis. CONCLUSIONS: This study suggests that the differentiation of the breast imprints a genomic signature that is centered in the mRNA processing reactome. These findings indicate that pregnancy may induce a safeguard mechanism at post-transcriptional level that maintains the fidelity of the transcriptional process.
    BMC Medical Genomics 10/2012; 5(1):46. · 3.91 Impact Factor
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    ABSTRACT: Men with familial prostate cancer and African American men are at risk for developing prostate cancer at younger ages. Genetic markers predicting early-onset prostate cancer may provide clinically useful information to guide screening strategies for high-risk men. We evaluated clinical information from six polymorphisms associated with early-onset prostate cancer in a longitudinal cohort of high-risk men enrolled in prostate cancer early detection with significant African American participation. Eligibility criteria include ages 35 to 69 with a family history of prostate cancer or African American race. Participants undergo screening and biopsy per study criteria. Six markers associated with early-onset prostate cancer [rs2171492 (7q32), rs6983561 (8q24), rs10993994 (10q11), rs4430796 (17q12), rs1799950 (17q21), and rs266849 (19q13)] were genotyped. Cox models were used to evaluate time to prostate cancer diagnosis and prostate-specific antigen (PSA) prediction for prostate cancer by genotype. Harrell's concordance index was used to evaluate predictive accuracy for prostate cancer by PSA and genetic markers. Four hundred and sixty participants with complete data and ≥ 1 follow-up visit were included. Fifty-six percent were African American. Among African American men, rs6983561 genotype was significantly associated with earlier time to prostate cancer diagnosis (P = 0.005) and influenced prediction for prostate cancer by the PSA (P < 0.001). When combined with PSA, rs6983561 improved predictive accuracy for prostate cancer compared with PSA alone among African American men (PSA = 0.57 vs. PSA + rs6983561 = 0.75, P = 0.03). Early-onset marker rs6983561 adds potentially useful clinical information for African American men undergoing prostate cancer risk assessment. Further study is warranted to validate these findings. Genetic markers of early-onset prostate cancer have potential to refine and personalize prostate cancer early detection for high-risk men.
    Cancer Epidemiology Biomarkers &amp Prevention 12/2011; 21(1):53-60. · 4.56 Impact Factor
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    ABSTRACT: In laboratory studies, acquired resistance to long-term antihormonal therapy in breast cancer evolves through two phases over 5 y. Phase I develops within 1 y, and tumor growth occurs with either 17β-estradiol (E(2)) or tamoxifen. Phase II resistance develops after 5 y of therapy, and tamoxifen still stimulates growth; however, E(2) paradoxically induces apoptosis. This finding is the basis for the clinical use of estrogen to treat advanced antihormone-resistant breast cancer. We interrogated E(2)-induced apoptosis by analysis of gene expression across time (2-96 h) in MCF-7 cell variants that were estrogen-dependent (WS8) or resistant to estrogen deprivation and refractory (2A) or sensitive (5C) to E(2)-induced apoptosis. We developed a method termed differential area under the curve analysis that identified genes uniquely regulated by E(2) in 5C cells compared with both WS8 and 2A cells and hence, were associated with E(2)-induced apoptosis. Estrogen signaling, endoplasmic reticulum stress (ERS), and inflammatory response genes were overrepresented among the 5C-specific genes. The identified ERS genes indicated that E(2) inhibited protein folding, translation, and fatty acid synthesis. Meanwhile, the ERS-associated apoptotic genes Bcl-2 interacting mediator of cell death (BIM; BCL2L11) and caspase-4 (CASP4), among others, were induced. Evaluation of a caspase peptide inhibitor panel showed that the CASP4 inhibitor z-LEVD-fmk was the most active at blocking E(2)-induced apoptosis. Furthermore, z-LEVD-fmk completely prevented poly (ADP-ribose) polymerase (PARP) cleavage, E(2)-inhibited growth, and apoptotic morphology. The up-regulated proinflammatory genes included IL, IFN, and arachidonic acid-related genes. Functional testing showed that arachidonic acid and E(2) interacted to superadditively induce apoptosis. Therefore, these data indicate that E(2) induced apoptosis through ERS and inflammatory responses in advanced antihormone-resistant breast cancer.
    Proceedings of the National Academy of Sciences 11/2011; 108(47):18879-86. · 9.81 Impact Factor
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    ABSTRACT: Early pregnancy and multiparity are known to reduce the risk of women to develop breast cancer at menopause. Based on the knowledge that the differentiation of the breast induced by the hormones of pregnancy plays a major role in this protection, this work was performed with the purpose of identifying what differentiation-associated molecular changes persist in the breast until menopause. Core needle biopsies (CNB) obtained from the breast of 42 nulliparous (NP) and 71 parous (P) postmenopausal women were analyzed in morphology, immunocytochemistry and gene expression. Whereas in the NP breast, nuclei of epithelial cells were large and euchromatic, in the P breast they were small and hyperchromatic, showing strong methylation of histone 3 at lysine 9 and 27. Transcriptomic analysis performed using Affymetrix HG_U133 oligonucleotide arrays revealed that in CNB of the P breast, there were 267 upregulated probesets that comprised genes controlling chromatin organization, transcription regulation, splicing machinery, mRNA processing and noncoding elements including XIST. We concluded that the differentiation process induced by pregnancy is centered in chromatin remodeling and in the mRNA processing reactome, both of which emerge as important regulatory pathways. These are indicative of a safeguard step that maintains the fidelity of the transcription process, becoming the ultimate mechanism mediating the protection of the breast conferred by full-term pregnancy.
    International Journal of Cancer 10/2011; 131(5):1059-70. · 6.20 Impact Factor
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    ABSTRACT: The objective of this study was to comprehensively compare the genomic profiles in the breast of parous and nulliparous postmenopausal women to identify genes that permanently change their expression following pregnancy. The study was designed as a two-phase approach. In the discovery phase, we compared breast genomic profiles of 37 parous with 18 nulliparous postmenopausal women. In the validation phase, confirmation of the genomic patterns observed in the discovery phase was sought in an independent set of 30 parous and 22 nulliparous postmenopausal women. RNA was hybridized to Affymetrix HG_U133 Plus 2.0 oligonucleotide arrays containing probes to 54,675 transcripts, scanned and the images analyzed using Affymetrix GCOS software. Surrogate variable analysis, logistic regression, and significance analysis of microarrays were used to identify statistically significant differences in expression of genes. The false discovery rate (FDR) approach was used to control for multiple comparisons. We found that 208 genes (305 probe sets) were differentially expressed between parous and nulliparous women in both discovery and validation phases of the study at an FDR of 10% and with at least a 1.25-fold change. These genes are involved in regulation of transcription, centrosome organization, RNA splicing, cell-cycle control, adhesion, and differentiation. The results provide initial evidence that full-term pregnancy induces long-term genomic changes in the breast. The genomic signature of pregnancy could be used as an intermediate marker to assess potential chemopreventive interventions with hormones mimicking the effects of pregnancy for prevention of breast cancer.
    Cancer Prevention Research 05/2011; 4(9):1457-64. · 4.89 Impact Factor
  • Journal of Surgical Research - J SURG RES. 01/2011; 165(2):220-220.
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    ABSTRACT: Negative margins in breast conservation therapy (BCT) decrease local recurrence risk. Excision may be performed via two techniques: either as a single lumpectomy specimen or as a central segment with simultaneously resected peripheral segments (PSs). There is little data directly comparing these methods for their effect on margin status. A retrospective review of all patients undergoing BCT for invasive breast cancer was conducted to evaluate and compare the two techniques. Presentation, pathologic characteristics, surgical technique, specimen volume, and final margin status were recorded. Among 259 cancers in 257 women, 33 had positive margins. A single segment was removed in 69 patients, while 190 patients had 1-6 PSs simultaneously removed. By univariate analysis, smaller tumor size (P = .017) and greater numbers of segments removed (P = .01) lowered the risk of positive margins. In a multivariate model, smaller tumor size (P = .0024), lack of EIC (P = .049), and greater numbers of segments removed (P = .0061) lowered the risk of margin positivity. Despite this last predictor, the total resected specimen volume did not increase with the number of PSs removed (P = .4). There was no residual tumor in 49.2% of PSs despite a compromised primary segment margin. Smaller tumor size, lack of EIC, and greater numbers of simultaneous PSs excised decrease the likelihood of positive margins, despite a lack of correlation between segment numbers and excised volume. These findings suggest that excision of simultaneous PSs may assist in achieving negative margins, in part, because of avoidance of pathologic artifact.
    Annals of Surgical Oncology 11/2010; 17(11):2933-9. · 4.12 Impact Factor
  • Journal of Clinical Oncology 08/2010; · 18.04 Impact Factor
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    ABSTRACT: We have previously demonstrated that prolonged treatments with raloxifene (RAL) in vitro will result in phase II RAL resistance and RAL-induced tumor growth. Clinical interest prompted us to re-examine RAL resistance in vivo, particularly the effects of long-term treatments (a decade or more) on the evolution of RAL resistance. In this study, we have addressed the question of this being a reproducible phenomenon in wild-type estrogen receptor (ER)-positive human breast cell line MCF-7. MCF-7 cells cultured under estrogen-deprived conditions in the presence of 1 microM RAL for more than a year develop RAL resistance resulting in an independent cell line, MCF7-RAL. The MCF7-RAL cells grow in response to both estradiol E2 and RAL. Fulvestrant (FUL) blocks RAL and E2-mediated growth. Transplantation of MCF7-RAL cells into athymic ovariectomized mice and treatment with physiologic doses of E2 causes early E2-stimulated tumor growth. In contrast, continuous treatment of implanted animals with daily oral RAL (1.5 mg daily) causes growth of small tumors within 15 weeks. Continuous re-transplantation of the tumors growing in RAL-treated mice indicated that RAL stimulated tumor growth. Tumors in the untreated mice did not grow. Bi-transplantation of MCF7-E2 and MCF7-RAL tumors into the opposing mammary fat pads of the same ovariectomized animal demonstrated that MCF7-E2 grew with E2 stimulation and not with RAL. Conversely, MCF7-RAL tumors grew with RAL and not E2, a characteristic of phase II resistance. Established phase II resistance of MCF7-RAL tumors was confirmed following up to 7 years of serial transplantation in RAL-treated athymic mice. The ERalpha was retained in these tumors. The cyclical nature of RAL resistance was confirmed and extended during a 2-year evolution of the resistant phases of the MCF7-RAL tumors. The MCF7-RAL tumors that initially were inhibited by E2 grew in the presence of E2 and subsequently grew with either RAL or E2. RAL remained the major grow stimulus and RAL enhanced E2-stimulated growth. Subsequent transplantation of E2 stimulated tumors and evaluations of the actions of RAL, demonstrated robust E2-stimulated growth that was blocked by RAL. These are the characteristics of the anti-estrogenic actions of RAL on E2-stimulated breast cancer growth with a minor component of phase I RAL resistance. Continuous transplantation of the phase I RAL-stimulated tumors for >8 months causes reversion to phase II resistance. These data and literature reports of the cyclical nature of anti-androgen/androgen responsiveness of prostate cancer growth, illustrate the generality of the evolution of anti-hormonal resistance in sex steroid-sensitive target tissues.
    International Journal of Oncology 08/2010; 37(2):387-98. · 2.66 Impact Factor

Publication Stats

1k Citations
328.37 Total Impact Points

Institutions

  • 1998–2014
    • Fox Chase Cancer Center
      • • Department of Radiation Oncology
      • • Department of Surgery
      Philadelphia, Pennsylvania, United States
  • 2013
    • George Mason University
      • Department of Health Administration and Policy
      Fairfax, VA, United States
  • 2010
    • Dartmouth–Hitchcock Medical Center
      Lebanon, New Hampshire, United States
  • 2002
    • Temple University
      • Section of Surgical Oncology
      Philadelphia, PA, United States