Denis R Clohisy

University of Minnesota Duluth, Duluth, Minnesota, United States

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Publications (63)310.74 Total impact

  • Patrick W. O’Donnell · Denis R. Clohisy
    Bone Cancer, 01/2015: pages 571-577; , ISBN: 9780124167216
  • International journal of radiation oncology, biology, physics 09/2014; 90(1):S765. DOI:10.1016/j.ijrobp.2014.05.2215 · 4.26 Impact Factor
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    ABSTRACT: Background and objectives:: The purpose of this study was to review the outcomes after preoperative radiotherapy and definitive surgery for patients who initially had inadvertent excision for sarcoma. Materials and methods:: Treatment records of 44 consecutive patients, who initially underwent unplanned excision of soft-tissue sarcoma between January 2004 and January 2012, were reviewed. All patients had clinically localized disease before treatment and received preoperative external-beam radiotherapy followed by definitive oncologic surgery at our institution. Results:: The median follow-up was 36 months. Residual tumor after preoperative radiotherapy and wound bed excision was identified in 39% (17/44) of the cases. Kaplan-Meier estimates for 5-year local control, recurrence-free survival, and overall survival are 95% (95% confidence interval [CI], 80-99), 86% (95% CI, 69-94), and 94% (95% CI, 79-99) respectively. Perioperative morbidity occurred in 25% of patients (11/44.) All patients with perioperative wound complications had lower extremity sarcomas. Conclusions:: Optimal management for unplanned excision of soft-tissue sarcoma is unknown. Our institution has adopted the approach of preoperative radiotherapy, followed by definitive surgery. In our series of 44 patients, local control was excellent at 95%, with perioperative complications seen only in patients with lower extremity sarcomas, suggesting that this is a reasonable approach to manage inadvertently resected sarcoma.
    International Journal of Radiation OncologyBiologyPhysics 05/2014; 87(2). DOI:10.1097/COC.0000000000000095 · 4.26 Impact Factor
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    ABSTRACT: Background: Cardiovascular-related toxicities have been reported among survivors of osteosarcoma. Methods: Fasting blood samples from 24 osteosarcoma survivors were analyzed for high-sensitivity C-reactive protein (hsCRP), triglycerides, total cholesterol, high-density lipoprotein (HDL), apolipoprotein-ß, lipoprotein (a), fibrinogen, circulating endothelial cells (CECs), and surface expression of vascular cell adhesion molecule-1 (VCAM-1). Values were compared to subjects in the natural history Coronary Artery Risk Development in Young Adults (CARDIA) cohort study except for CECs and VCAM-1 expression, which were compared to controls studied at the University of Minnesota Lillehei clinical trials unit. Procedure: Survivors (54.2% male), median age 18 years (9-32) at diagnosis, 36.5 years (20-56) at evaluation were treated with a variety of chemotherapeutic exposures, all but one were exposed to doxorubicin (median dose 450 mg/m(2) ; range: 90-645 mg/m(2)), 14 (58.3%) received cisplatin, and 3 (12.5%) were exposed to carboplatin. Two survivors (8.3%) received radiation therapy for disease relapse. Compared to CARDIA subjects, mean hsCRP (3.0 mg/L ± 2.0 vs. 1.6 ± 2.3), triglycerides (151 mg/dl ± 81.7 vs. 95.4 ± 101.3), lipoprotein (a) (34.9 mg/dl ± 17.7 vs. 13.8 ± 22.0), and fibrinogen (315.0 mg/dl ± 49.3 vs. 252.4 ± 61.7) were significantly elevated. The number of CECs (0.47 cells/ml ± 2.5 vs. 0.92 ± 2.5) did not differ while surface expression of VCAM-1 (86.4% ± 34.0 vs. 42.1 ± 33.8) was significantly elevated compared to controls. Conclusions: Among survivors of osteosarcoma, assessed a median of 14 years from diagnosis, there is evidence of vascular inflammation, dyslipidemia, and early atherogenesis.
    Pediatric Blood & Cancer 10/2013; 60(10). DOI:10.1002/pbc.24610 · 2.39 Impact Factor
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    ABSTRACT: BACKGROUND: Soft tissue sarcomas are a heterogeneous group of malignant tumors. Standard treatment for soft tissue sarcoma of the extremity is surgical excision and adjuvant therapy; however, the role of neoadjuvant chemotherapy is controversial. QUESTIONS/PURPOSES: We sought to (1) define the histologic characteristics of the pseudocapsule in soft tissue sarcomas; (2) compare the appearance of this structure in chemotherapy-treated versus untreated soft tissue sarcomas; and (3) evaluate the effect of chemotherapy on the presence and viability of tumor cells at the host-sarcoma interface. METHODS: Twenty-eight patients with biopsy-proven, deep, high-grade extremity soft tissue sarcomas greater than 5 cm (AJCC stage III) treated with chemotherapy and surgical excision were compared histologically with 47 matched control subjects treated with surgery alone. RESULTS: A pseudocapsule was identifiable in the majority of tumors and consisted of two identifiable layers, each with specific histological characteristics suggesting the biologic processes occurring in these layers are different. The pseudocapsule was more frequently observed in the group treated with chemotherapy and it was more frequently continuous, thicker, and better developed in this group. Chemotherapy decreased the number of tumors with malignant cells identified within and beyond the pseudocapsule. CONCLUSIONS: Neoadjuvant chemotherapy contributed to the development of a pseudocapsule and decreased the number of tumors with malignant cells identified within and beyond the pseudocapsule. CLINICAL RELEVANCE: These findings may provide a histological explanation for the clinical effect of chemotherapy in soft tissue sarcoma. LEVEL OF EVIDENCE: Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
    Clinical Orthopaedics and Related Research 05/2013; 472(3). DOI:10.1007/s11999-013-3022-7 · 2.77 Impact Factor
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    Margaret L Ramnaraine · Wendy E Mathews · Denis R Clohisy
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    ABSTRACT: Gene transfer into stem cells has been an ongoing priority as a treatment for genetic disease and cancer for more than two decades. Methods described herein, form the basis for providing the cell source to determine if osteoclast precursor cells (OcP) can be used as therapeutic gene delivery systems in vivo. Osteoclasts and tumor associated macrophages or OcP, support survival, tumor progression and osteolysis in bone cancers. Two sources of precursor cells are compared: CD14+ cells, the standard OcP, found abundantly in peripheral blood and CD34+ cells, hematopoietic stem cells that are rare, but which can be expanded into OcP. Our findings characterize cell yield at each step of the transduction process and thus provide essential data for planning future in vivo experiments. In addition we demonstrate that essential functions of OcP are preserved following lentiviral transduction. Specifically, neither the transduction method nor the lentiviral transduction influence the OcP's ability to form osteoclasts, express the marker gene, EGFP, or resorb bone. Finally, we conclude that CD34+ cells yield significantly more transduced cells and form functionally superior osteoclasts in vitro. This study represents a step towards considering human gene therapy for bone cancer by demonstrating successful transduction of human OcP for use as cellular delivery vehicles to sites of bone cancer.
    Bone 01/2012; 50(1):97-103. DOI:10.1016/j.bone.2011.09.050 · 3.97 Impact Factor
  • Patrick W. O’Donnell · Nancy M. Luger · Denis R. Clohisy
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    ABSTRACT: In 2005, cancer was second only to heart disease as the leading cause of death in the United States. There are 1.4 million new cases of cancer diagnosed each year resulting in over one-half of a million deaths. Due to improvements in detection and treatment, longer patient survival after diagnosis is now possible. Unfortunately, the quality of life in patients dealing with advanced cancer is significantly reduced. A major contributor to the overall decreased quality of life in such patients is bone cancer pain [12, 45].
    06/2009: pages 167-179;
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    ABSTRACT: Aggressive fibromatosis (AF) is usually a slowly growing locally invasive tumor, but may exhibit a much more aggressive phenotype. The role of chemotherapy in AF is not well defined, but can be useful in some cases. We examined the response of a case to both imatinib and sunitinib. We report a case of an aggressive multicentric extra-abdominal AF that was responsive to sunitinib, but resistant to imatinib. A 23-year-old woman developed painful multifocal AF of both legs and gluteal muscles that progressed after surgery and treatment with methotrexate/vinblastine and pegylated-liposomal doxorubicin. She received six cycles of ifosfamide/etoposide (IMV), and obtained a good response with elimination of pain. After 5 months, she developed progression and again received six cycles of IMV, with cessation of symptoms. After 13 months, tumors recurred. Although the AF was symptomatic and progressing, she was hesitant to receive chemotherapy and began treatment with sunitinib 50 mg/day for 28 days of a 42-day cycle. At 4 months, she could walk on her heels without pain. After 13 months of sunitinib, therapy was changed to imatinib 400 mg/day; after 7 days she noticed increasing pain in the AF lesions and decreased knee flexibility. Imatinib was continued, but after 2 months of imatinib, she could only walk a few steps due to pain. Sunitinib was reinstituted at 37.5 mg/day and symptoms improved within 1.5 weeks, with a marked reduction of symptoms at 1 month. She was doing well with a normal activity level, 32 months after initially beginning sunitinib. We conclude that sunitinib may be useful in some cases of AF.
    Cancer Chemotherapy and Pharmacology 05/2009; 64(3):635-40. DOI:10.1007/s00280-009-1010-0 · 2.77 Impact Factor
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    ABSTRACT: Subpubic cartilaginous cysts were initially described in 1996 with few reports to date. We describe a 62-year-old woman with a history of breast cancer who presented with a painful, fixed, vulvar mass. MRI revealed an 18 x 10 x 12 mm3 mass extending from the anterior portion of the symphysis pubis without bony involvement. Excision was performed. Histologically, the mass consisted of fibrocartilage with extensive degenerative changes, compatible with a subpubic cartilaginous cyst. Over 24 months later, there has been no recurrence. Subpubic cartilaginous cyst is a rare, benign lesion occurring on the vulva and should be considered in the differential diagnosis of a painful, superior vulvar mass.
    Archives of Gynecology 12/2008; 280(1):107-9. DOI:10.1007/s00404-008-0847-5 · 1.36 Impact Factor
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    ABSTRACT: The receptor tyrosine kinase inhibitor, SU11248, was added to localised radiation to evaluate the response of bone metastases and to define the basic mechanism of radiosensitisation. Treatment with SU11248 and radiation was assessed in vitro using cultured 4T1 breast cancer cells and in vivo using an orthotopic 4T1 murine mammary tumour model of breast cancer bone metastasis. Cultured 4T1 cells treated with SU11248 (1 microM) and radiation (10 Gy) showed an almost 7.5-fold increase in caspase-mediated apoptosis after 24 h of incubation, compared to either treatment alone. Mice treated with SU11248 (40 mg/kg/daily) and radiation (15 Gy/single-dose) had a relatively greater reduction in tumour growth, bone osteolysis, osteoclast maturation and microvessel density. Combined modality treatment resulted in improvements in behavioural pain assessment scores and normalisation of neurochemical changes in the spinal cord receiving primary afferent innervation from tumour-bearing femora. Our study demonstrates that SU11248 enhances the radiation control of metastatic breast tumours in bone and tumour-induced pain.
    European journal of cancer (Oxford, England: 1990) 09/2008; 44(16):2506-17. DOI:10.1016/j.ejca.2008.07.011 · 5.42 Impact Factor
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    Balaji Krishnan · Gaurav Khanna · Denis Clohisy
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    ABSTRACT: Establishing the best diagnosis for musculoskeletal neoplasms requires a multidisciplinary approach using clinical, radiographic, and histologic analyses. Despite this rigorous approach, establishing accurate diagnoses and prognoses remains challenging. Improved diagnostic methods are expected as unique molecular signals for specific bone and soft tissue cancers are identified. We performed a systematic review of the best available evidence to explore three major applications of molecular genetics that will best benefit clinical management of musculoskeletal neoplasms: diagnostic, prognostic, and therapeutic applications. The specific questions addressed in this systematic review are: (1) What sets of histopathologic sarcoma subtypes will benefit from molecular evaluation and diagnosis? (2) What molecular methods are best applied to histopathologic sarcomas to distinguish between major subtypes? (3) How do the molecular patterns discovered on genetic diagnosis affect prognosis of certain sarcomas? (4) Which sarcoma translocations can benefit from an improved response and outcome using existing and forthcoming pharmacogenetic approaches targeting molecular events? This review summarizes recent advances in molecular genetics that are available and will soon be available to clinicians to better predict outcomes and subsequently help make future treatment decisions. Level of Evidence: Level IV, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.
    Clinical Orthopaedics and Related Research 07/2008; 466(9):2131-46. DOI:10.1007/s11999-008-0342-0 · 2.77 Impact Factor
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    ABSTRACT: Skeletal metastases are a major source of morbidity for cancer patients. The purpose of this study was to evaluate the effects of megavoltage irradiation and antiangiogenic therapy on metastatic bone cancer. A tumor xenograft model was prepared in C3H/Scid mice using 4T1 murine breast carcinoma cells. Twenty-eight mice bearing tumors were treated with either bevacizumab (15 mg/kg), local megavoltage irradiation (30 Gy in 1 fraction), combination of bevacizumab and local megavoltage irradiation or physiologic saline solution (control group). Tumor area, bone destruction, tumor microvessel density, pain-associated behaviors and expression of substance P were assessed. Combined modality treatment reduced the frequency of pain-associated behaviors, decreased levels of nociceptive protein expression in the spinal cord, maintained cortical integrity and decreased the density of microvessels as compared to single modality treatments. We conclude that concurrent antiangiogenic therapy and localized radiotherapy for the treatment of bone metastases warrants further evaluation in human clinical trials.
    International Journal of Cancer 02/2008; 122(3):681-8. DOI:10.1002/ijc.23157 · 5.09 Impact Factor
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    ABSTRACT: 2-Methoxyestradiol (2ME(2)), a physiologic metabolite of 17beta-estradiol (estrogen), has emerged as a promising cancer therapy because of its potent growth-inhibitory and proapoptotic effects on both endothelial and tumor cells. 2ME(2) also suppresses osteoclast differentiation and induces apoptosis of mature osteoclasts, and has been shown to effectively repress bone loss in an animal model of postmenopausal osteoporosis. Given these observations, we have examined whether 2ME(2) could effectively target metastasis to bone, osteolytic tumors, and soft tissue tumors. A 4T1 murine metastatic breast cancer cell line was generated that stably expressed Far Red fluorescence protein (4T1/Red) to visualize tumor development and metastasis to bone. In an intervention study, 4T1/Red cells were injected into bone marrow of the left femur and the mammary pad. In the latter study, 2ME(2) (10, 25, and 50 mg/kg/d) treatment began on the same day as surgery and was continued for the 16-day duration of study. Tumor cell growth and metastasis to bone were monitored and bone volume was determined by micro-computed tomography. 2ME(2) inhibited tumor growth in soft tissue, metastasis to bone, osteolysis, and tumor growth in bone, with maximum effects at 50 mg/kg/d. Furthermore, tumor-induced osteolysis was significantly reduced in mice receiving 2ME(2). In vitro, 2ME(2) repressed osteoclast number by inducing apoptosis of osteoclast precursors as well as mature osteoclasts. Our data support the conclusion that 2ME(2) could be an important new therapy in the arsenal to fight metastatic breast cancer.
    Cancer Research 12/2007; 67(21):10106-11. DOI:10.1158/0008-5472.CAN-07-1362 · 9.33 Impact Factor
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    ABSTRACT: The best treatment for intramuscular hemangiomas is unclear in part because the outcome is variable, with recurrence rates ranging from 18% to 61%. This variance is due to deficiencies in previous reports such as an inadequate population size, lack of life table analyses, lack of uniform pathologic criteria, and loose or absent definition of surgical margins. Our goal was to address these deficiencies and support or refute previous results. We identified 110 patients between 1981 and 2005. There were 48 males and 62 females with an average age of 22 years at the time of consult. Kaplan-Meier analysis showed 76% of patients managed initially without excision were surgery-free at 2 years and 66% at 5 years. For patients treated with surgery, 86% and 73% were recurrence free at 2 and 5 years, respectively. There were substantial differences in local recurrence when stratified by margin: 93% of patients were recurrence free at 5 years when the excision was marginal and wide, 65% when intralesional without any gross remaining tumor, and 33% when intralesional with gross remaining tumor. Surgical margins and tumor size were the only identified risk factors for recurrence.
    Clinical Orthopaedics and Related Research 07/2007; 459(459):186-91. DOI:10.1097/BLO.0b013e318063c61b · 2.77 Impact Factor
  • Pawel Zwolak · Carlos Manivel · Denis R Clohisy
    Clinical Orthopaedics and Related Research 06/2007; 458:235-40. DOI:10.1097/ · 2.77 Impact Factor
  • Michael J Goblirsch · Pawel P Zwolak · Denis R Clohisy
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    ABSTRACT: Bone cancer pain is a devastating manifestation of metastatic cancer. Unfortunately, current therapies can be ineffective, and when they are effective, the duration of the patient's survival typically exceeds the duration of pain relief. New, mechanistically based therapies are desperately needed. Study of experimental animal models has provided insight into the mechanisms that drive bone cancer pain and provides an opportunity for developing targeted therapies. Mechanisms that drive bone cancer pain include tumor-directed osteoclast-mediated osteolysis, tumor cells themselves, tumor-induced nerve injury, stimulation of transient receptor potential vanilloid type 1 ion channel, endothelin A, and host cell production of nerve growth factor. Current and future therapies include external beam radiation, osteoclast-targeted inhibiting agents, anti-inflammatory drugs, transient receptor potential vanilloid type 1 antagonists, and antibody therapies that target nerve growth factor or tumor angiogenesis. It is likely that a combination of these therapies will be superior to any one therapy alone.
    Clinical Cancer Research 11/2006; 12(20 Pt 2):6231s-6235s. DOI:10.1158/1078-0432.CCR-06-0682 · 8.72 Impact Factor
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    ABSTRACT: Primary and metastatic bone cancers are difficult to eradicate and novel approaches are needed to improve treatment and extend life. As bone cancer grows, osteoclasts, the principal bone-resorbing cells of the body, are recruited to and activated at sites of cancer. In this investigation, we determined if osteoclast lineage cells could function as a cell-based gene delivery system to bone cancers. We used the cytosine deaminase (CD) 5-fluorocytosine (5-FC) enzyme/prodrug system and studied bone marrow and bones from transgenic mice expressing a novel CD gene regulated by the osteoclast tartrate-resistant acid phosphatase (TRAP) gene promoter (Tg/NCD). DsRed2-labeled 2472 sarcoma cells were placed in Tg/NCD osteoclastogenic cultures and treated with 5-FC. 5-FC treatment resulted in profound bystander killing (90%; P < 0.05). The effect of 5-FC treatment on osteoclast lineage cells was most dramatic when administered at the beginning of the 7-day cultures, suggesting that mature osteoclasts are less sensitive to 5-FC. Evaluation of osteoclast-directed bystander killing in vivo revealed dramatic killing of bone cancer with only a modest effect on osteoclast number. Specifically, 5-FC treatment of tumor-bearing Tg/NCD mice or Tg/NCD bone marrow transplanted C3H mice (Tg/NCD-C3H) resulted in 92% and 44% reductions in tumor area, respectively (P < 0.05). Eight of ten 5-FC-treated Tg/NCD mice had complete bone tumor killing and five of six 5-FC-treated Tg/NCD-C3H mice had reduced tumor compared with controls. In addition, Tg/NCD osteoclasts were resistant to 5-FC treatment in vivo, a very important feature, as it identifies osteoclasts as an ideal CD gene delivery system.
    Cancer Research 11/2006; 66(22):10929-35. DOI:10.1158/0008-5472.CAN-06-1295 · 9.33 Impact Factor
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    ABSTRACT: The First Cambridge Conference on Advances in Treating Metastatic Bone Cancer, a symposium held in Cambridge, Massachusetts, October 28 to 29, 2005, was convened to discuss recent advances and research related to the natural history of bone metastases and skeletal complications, bone cancer biology, treatment of myeloma and other solid tumors, and treatment-induced bone loss. The conference format combined brief presentations with extended periods of discussion. The conclusions reached during the 2-day meeting are summarized in this article and presented in more detail in the individual articles and accompanying discussion sessions that comprise the conference proceedings.
    Clinical Cancer Research 11/2006; 12(20 Pt 2):6209s-6212s. DOI:10.1158/1078-0432.CCR-06-1213 · 8.72 Impact Factor
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    ABSTRACT: Painful breast carcinoma metastases in bone are a common manifestation of malignant disease. Eradication of these tumors can be evasive, and as a result, skeletal morbidity increases with disease progression. The treatment potential of cytosine deaminase (CD) gene therapy combined with radiation treatment was evaluated in vitro and in vivo using a 4T1 murine breast carcinoma model. 4T1 carcinoma cells were transduced with a fusion gene encoding the extracellular and transmembrane domains of the human nerve growth factor receptor and the cytoplasmic portion of the yeast CD gene (NGFR-CD(y)). CD-expressing tumor cells (4TCD(y)) were highly sensitive to treatment by 5-fluorocytosine prodrug (P < 0.0001). 5-Fluorocytosine treatment of 4TCD(y), but not 4T1 cells, enhanced the effects of radiation in vitro (P < 0.0001). 5-Fluorocytosine prodrug treatment also increased the therapeutic potential of radiation in vivo. Mice with 4TCD(y) intrafemoral tumors showed increased effectiveness of radiation based on improved reductions in tumor size, reductions in tumorigenic osteolysis, and a decrease in skeletal fractures (P < 0.01).
    Clinical Cancer Research 06/2006; 12(10):3168-76. DOI:10.1158/1078-0432.CCR-05-2729 · 8.72 Impact Factor
  • Daniel J Selski · Denis R Clohisy
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    ABSTRACT: Osteoclasts play a seminal role in many skeletal diseases and therefore are candidates for cell-based gene delivery systems to treat disorders of bone. As an initial step toward developing osteoclast-mediated gene delivery systems, we have made and analyzed a customized Molony-Murine leukemia virus (MMLV)-based retroviral vector containing elements of the osteoclast-specific tartrate-resistant acid phosphatase (TRAP) gene. RAW 264.7 cells were transduced with the customized vector (E3) and differentiated along macrophage or osteoclast lineages. E3 contained a truncated form of the human nerve growth factor receptor (NGFR) as a reporter gene. NGFR expression increased with RANK-ligand (RANK-L) treatment but not with macrophage (gamma-IFN/LPS treatment) differentiation. Enhanced NGFR expression peaked 48 h after RANK-L treatment. Electrophoretic mobility shift assays (EMSA) analysis of the TRAP gene regulatory elements in E3 identified a single 27 bp DNA probe, which specifically bound protein from RANK-L-treated cells. DNA sequence revealed AP-1 binding sites, and analysis with mutant probes implied that the sites were functional. EMSA supershift analysis identified Fos protein interacting with the 27 bp probe. In summary, insertion of sequence -962 to -868 from the TRAP gene into the U3 region of the MMLV LTR confers RANK-L induced retroviral gene expression via Fos family protein interaction at AP-1 sites.
    Journal of Cellular Biochemistry 02/2006; 97(3):641-50. DOI:10.1002/jcb.20679 · 3.26 Impact Factor

Publication Stats

3k Citations
310.74 Total Impact Points


  • 1995–2013
    • University of Minnesota Duluth
      • • Laboratory Medicine and Pathology
      • • Medical School
      Duluth, Minnesota, United States
  • 2008
    • University of Minnesota Twin Cities
      • Department of Orthopaedic Surgery
      Minneapolis, Minnesota, United States
  • 2005
    • Beth Israel Deaconess Medical Center
      Boston, Massachusetts, United States