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Dive into the research topics where H. Richard Alexander is active.

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Featured researches published by H. Richard Alexander.


Clinical Cancer Research | 2010

Phase I and Pharmacokinetic Studies of CYT-6091, a Novel PEGylated Colloidal Gold-rhTNF Nanomedicine

Steven K. Libutti; Giulio F. Paciotti; Adriana A. Byrnes; H. Richard Alexander; William E. Gannon; Melissa Walker; Geoffrey Seidel; Nargiza Yuldasheva; Lawrence Tamarkin

Purpose: A novel nanomedicine, CYT-6091, constructed by simultaneously binding recombinant human tumor necrosis factor alpha (rhTNF) and thiolyated polyethylene glycol to the surface of 27-nm colloidal gold particles, was tested in a phase I dose escalation clinical trial in advanced stage cancer patients. Experimental Design: CYT-6091, whose dosing was based on the amount of rhTNF in the nanomedicine, was injected intravenously, and 1 cycle of treatment consisted of 2 treatments administered 14 days apart. Results: Doses from 50 μg/m2 to 600 μg/m2 were well tolerated, and no maximum tolerated dose (MTD) was reached, as the highest dose exceeded the target dosage of 1-mg rhTNF per treatment, exceeding the previous MTD for native rhTNF by 3-fold. The first 2 patients on the study, each receiving 50 μg/m2, did not receive any prophylactic antipyretics or H2 blockade. A predicted, yet controllable fever occurred in these patients, so all subsequently treated patients received prophylactic antipyretics and H2 blockers. However, even at the highest dose rhTNFs dose-limiting toxic effect of hypotension was not seen. Using electron microscopy to visualize nanoparticles of gold in patient biopsies of tumor and healthy tissue showed that patient biopsies taken 24 hours after treatment had nanoparticles of gold in tumor tissue. Conclusions: These data indicate that rhTNF formulated as CYT-6091 may be administered systemically at doses of rhTNF that were previously shown to be toxic and that CYT-6091 may target to tumors. Future clinical studies will focus on combining CYT-6091 with approved chemotherapies for the systemic treatment of nonresectable cancers. Clin Cancer Res; 16(24); 6139–49. ©2010 AACR.


Journal of Clinical Oncology | 2003

Analysis of Factors Associated With Outcome in Patients With Malignant Peritoneal Mesothelioma Undergoing Surgical Debulking and Intraperitoneal Chemotherapy

Andrew L. Feldman; Steven K. Libutti; James F. Pingpank; David L. Bartlett; Tatiana Beresnev; Sharon M. Mavroukakis; Seth M. Steinberg; David J. Liewehr; David E. Kleiner; H. Richard Alexander

PURPOSE Malignant mesothelioma (MM) arising in the peritoneal cavity is a rare neoplasm characterized by peritoneal progression and for which there are limited therapeutic options. We evaluated the peritoneal progression-free and overall survival (PFS and OS, respectively) for patients with peritoneal MM after surgical resection and regional chemotherapy. PATIENTS AND METHODS Forty-nine patients (28 males, 21 females; median age, 47 years; range, 16 to 76 years) with MM underwent laparotomy, tumor resection, continuous hyperthermic peritoneal perfusion with cisplatin (median dose 250 mg/m2), and a single postoperative intraperitoneal dwell of fluorouracil and paclitaxel (n = 35) on protocols approved by the Institutional Review Board. Standard techniques for actuarial analyses of potential prognostic variables (Kaplan-Meier method with two-tailed log-rank test and Cox proportional hazards model) were performed. RESULTS At a median potential follow-up of 28.3 months, median actuarial PFS is 17 months and actuarial OS is 92 months. Factors associated with improved PFS and OS by the Cox proportional hazards model were a history of previous debulking surgery, absence of deep tissue invasion, minimal residual disease after surgical resection (OS only), and age younger than 60 years (OS only). CONCLUSION Surgical resection and regional chemotherapy for MM results in durable PFS and OS. Favorable outcome is associated with age, tumor biology (selection of patients with a history of previous debulking), lack of invasive tumor growth, and minimal residual disease after tumor resection.


Cancer | 2003

Radiofrequency ablation of adrenal tumors and adrenocortical carcinoma metastases

Bradford J. Wood; Jame Abraham; L R N Julia Hvizda; H. Richard Alexander; Tito Fojo

The current study was performed to analyze the feasibility, safety, imaging appearance, and short‐term efficacy of image‐guided percutaneous radiofrequency ablation (RFA) of primary and metastatic adrenal neoplasms including adrenocortical carcinoma.


Annals of Surgery | 1996

A prospective trial evaluating a standard approach to reoperation for missed parathyroid adenoma.

Nora Jaskowiak; Jeffrey A. Norton; H. Richard Alexander; John L. Doppman; Thomas H. Shawker; Monica C. Skarulis; Stephen J. Marx; Allen M. Spiegel; Douglas L. Fraker

OBJECTIVES The authors evaluate the results of preoperative imaging protocols and surgical re-exploration in a series of patients with missed parathyroid adenomas after failed procedures for primary hyperparathyroidism. BACKGROUND The success rate is lower and the complication rate is increased in patients undergoing reoperation for primary hyperparathyroidism compared with initial procedures. Scarring and distortion of tissue planes plus the potential for ectopic gland location leads to this worsened outcome. METHODS Two hundred eighty-eight consecutive patients with persistent/recurrent hyperparathyroidism were treated at a single institution after a failed procedure or procedures at outside institutions. Two hundred twenty-two of these patients (77%) were believed to have a missed single adenoma, and these patients underwent 228 operations and 227 preoperative work-ups. Preoperative evaluation consisted of a combination of four noninvasive imaging studies--neck ultrasound, nuclear medicine scan, neck and mediastinal computed tomography scan, and neck and mediastinal magnetic resonance imaging. Based on the noninvasive testing alone, 27% patients underwent surgery whereas the other patients underwent invasive studies, including selective angiography (58%), selective venous sampling for parathyroid hormone (43%), or percutaneous aspiration of suspicious lesions (15%). RESULTS Abnormal parathyroid adenomas were found in 209 of 222 initial procedures and 6 of 6 second procedures, with an overall success rate in terms of resolution of hypercalcemia in 97% (215/222) of patients. The single most common site of missed adenoma glands was in the tracheal-esophageal groove in the posterior superior mediastinum (27%). The most common ectopic sites for parathyroid adenomas are thymus (17%), intrathyroidal (10%), undescended glands (8.6%), carotid sheath (3.6%), and the retroesophageal space (3.2%). The most sensitive and specific noninvasive imaging test is the sestamibi subtraction scan, with 67% true-positive and no false-positive results. The rate of true-positive and false-positive results for ultrasound, computed tomography, magnetic resonance imaging, and technetium thallium scans were 48%/21%, 52%/16%, 48%/14% and 42%/8%, respectively. The incidence of injury to the recurrent laryngeal nerve was 1.3%. CONCLUSIONS A single missed parathyroid adenoma is the most common cause for a failed initial parathyroid operation. Appropriate use of preoperative imaging tests and knowledge of the potential location or parathyroid adenomas can lead to very high cure rates with minimal morbidity.


Clinical Cancer Research | 2006

The role of interleukin 1 in growth and metastasis of human cancer xenografts.

Dina M. Elaraj; David M. Weinreich; Sheelu Varghese; Markus Puhlmann; Stephen M. Hewitt; Nancy M. Carroll; Elizabeth D. Feldman; Ewa M. Turner; H. Richard Alexander

BACKGROUND: Interleukin 1 (IL-1) is a pluripotent cytokine that promotes angiogenesis, tumor growth, and metastasis in experimental models; its presence in some human cancers is associated with aggressive tumor biology. The purpose of these studies was to characterize the role of IL-1 in human cancers and determine if inhibition of IL-1 via its receptor antagonist, IL-1Ra, alters tumor growth and metastatic potential. METHODS: IL-1 mRNA or protein levels were determined in clinical tumor samples, cancer cell lines, and xenografts using quantitative reverse transcription-PCR or ELISA. Biological activity of tumor-derived IL-1 protein was shown via induction of permeability across endothelial cell monolayers. The effects of recombinant IL-1Ra on tumor lines in culture (cell proliferation and IL-8 secretion) and in xenograft models (tumor growth, metastatic potential, and intratumoral levels of IL-8 and VEGF) were characterized. The effects of IL-1Ra-mediated regression of xenograft growth on angiogenic proteins (IL-8 and VEGF) were evaluated in an IL-1-producing melanoma (SMEL) xenograft model. RESULTS: IL-1 mRNA was highly expressed in more than half of all tested metastatic human tumor specimens including non-small-cell lung carcinoma, colorectal adenocarcinoma, and melanoma tumor samples. Constitutive IL-1 mRNA expression was identified in several cancer cell lines; tumor supernatant from these cell lines produced a significant increase in endothelial cell monolayer permeability, a hallmark event in early angiogenesis, in an IL-1-dependent manner. Moreover, systemic recombinant IL-1Ra resulted in significant inhibition of xenograft growth and neovessel density of IL-1-producing, but not non-IL-1-producing, tumor cell lines. Subsequent analysis of SMEL, a melanoma cell line with constitutive IL-1 production, showed that neither exogenous IL-1 nor IL-1Ra altered tumor cell proliferation rates in vitro. Gene expression analyses of IL-1Ra-treated SMEL xenografts showed a >3-fold down-regulation of 100 genes compared with control including a marked down-regulation of IL-8 and VEGF. CONCLUSIONS: These data show that the IL-1 gene is frequently expressed in metastases from patients with several types of human cancers. IL-1Ra inhibits xenograft growth in IL-1-producing tumors but has no direct antiproliferative effects in vitro; decreased tumor levels of IL-8 and VEGF may be an early surrogate of IL-1Ra-mediated antitumor activity. IL-1Ra may have a role alone or with other agents in the treatment of human cancers.


Cancer Research | 2004

Using Gene Expression Profiling to Differentiate Benign versus Malignant Thyroid Tumors

Chiara Maria Mazzanti; Martha A. Zeiger; Nick Costourous; Christopher B. Umbricht; William H. Westra; Danelle Smith; Helina Somervell; Generoso Bevilacqua; H. Richard Alexander; Steven K. Libutti

DNA microarrays allow quick and complete evaluation of a cells transcriptional activity. Expression genomics is very powerful in that it can generate expression data for a large number of genes simultaneously across multiple samples. In cancer research, an intriguing application of expression arrays includes assessing the molecular components of the neoplastic process and utilizing the data for cancer classification (Miller LD, et al. Cancer Cell 2002;2:353-61). Classification of human cancers into distinct groups based on their molecular profile rather than their histological appearance may prove to be more relevant to specific cancer diagnoses and cancer treatment regimes. Several attempts to formulate a consensus about classification and treatment of thyroid carcinoma based on standard histopathological analysis have resulted in published guidelines for diagnosis and initial disease management (Sherman SI. Lancet 2003;361:501-11). In the past few decades, no improvement has been made in the differential diagnosis of thyroid tumors by fine needle aspiration biopsy, specifically suspicious or indeterminate thyroid lesions, suggesting that a new approach to this should be explored. Therefore, in this study, we developed a gene expression approach to diagnose benign versus malignant thyroid lesions in 73 patients with thyroid tumors. We successfully built a 10 and 6 gene model able to differentiate benign versus malignant thyroid tumors. Our results support the premise that a molecular classification system for thyroid tumors is possible, and this in turn may provide a more accurate diagnostic tool for the clinician managing patients with suspicious thyroid lesions.


Annals of Surgery | 2001

Comparison of Surgical Results in Patients With Advanced and Limited Disease With Multiple Endocrine Neoplasia Type 1 and Zollinger-Ellison Syndrome

Jeffrey A. Norton; H. Richard Alexander; Douglas L. Fraker; David Venzon; Fathia Gibril; Robert T. Jensen

ObjectiveTo determine the role of surgery in patients with Zollinger-Ellison syndrome (ZES) and multiple endocrine neoplasia type 1 (MEN1) with either limited or advanced pancreatic endocrine tumors (PETs). Summary Background DataThe role of surgery in patients with MEN1 and ZES is controversial. There have been numerous previous studies of surgery in patients with PETs; however, there are no prospective studies on the results of surgery in patients with advanced disease. MethodsEighty-one consecutive patients with MEN1 and ZES were assigned to one of four groups depending on the results of imaging studies. Group 1 (n = 17) (all PETs smaller than 2.5 cm) and group 3 (n = 8) (diffuse liver metastases) did not undergo surgery. All patients in group 2A (n = 17; single PET 2.5–6 cm [limited disease]) and group 2B (n = 31; two or more lesions, 2.5 cm in diameter or larger, or one lesion larger than 6 cm) underwent laparotomy. Tumors were preferably removed by simple enucleation, or if not feasible resection. Patients were reevaluated yearly. ResultsPancreatic endocrine tumors were found in all patients at surgery, with groups 2A and 2B having 1.7 ± 0.4 and 4.8 ± 1 PETs, respectively. Further, 35% of the patients in group 2A and 88% of the patients in group 2B had multiple PETs, 53% and 84% had a pancreatic PET, 53% and 68% had a duodenal gastrinoma, 65% and 71% had lymph node metastases, and 0% and 12% had liver metastases. Of the patients in groups 2A and 2B, 24% and 58% had a distal pancreatectomy, 0% and 13% had a hepatic resection, 0% and 6% had a Whipple operation, and 53% and 68% had a duodenal resection. No patient was cured at 5 years. There were no deaths. The early complication rate, 29%, was similar for groups 2A and 2B. Mean follow-up from surgery was 6.9 ± 0.8 years, and during follow-up liver metastases developed in 6% of the patients in groups 2A and 2B. Groups 1, 2A, and 2B had similar 15-year survival rates (89–100%); they were significantly better than the survival rate for group 3 (52%). ConclusionsAlmost 40% of patients with MEN1 and ZES have advanced disease without diffuse distant metastases. Despite multiple primaries and a 70% incidence of lymph node metastases, tumor can be removed with no deaths and complication rates similar to those in patients with limited disease. Further, despite previous studies showing that patients with advanced disease have decreased survival rates, in this study the patients with advanced tumor who underwent surgical resection had the same survival as patients with limited disease and patients without identifiable tumor. This suggests that surgical resection should be performed in patients with MEN1 who have ZES and advanced localized PET.


Annals of the New York Academy of Sciences | 2004

Molecular Pathology of the MEN1 Gene

Sunita K. Agarwal; A. Lee Burns; Karen E. Sukhodolets; Patricia A. Kennedy; Victor H. Obungu; Alison Burgess Hickman; Michael E. Mullendore; Ira Whitten; Monica C. Skarulis; William F. Simonds; Carmen M. Mateo; Judy S. Crabtree; Peter C. Scacheri; Youngmi Ji; Elizabeth A. Novotny; Lisa Garrett-Beal; Jerrold M. Ward; Steven K. Libutti; H. Richard Alexander; Aniello Cerrato; Michael Parisi; Sonia Santa Anna-A; Brian Oliver; Settara C. Chandrasekharappa; Francis S. Collins; Allen M. Spiegel; Stephen J. Marx

Abstract: Multiple endocrine neoplasia type 1 (MEN1), among all syndromes, causes tumors in the highest number of tissue types. Most of the tumors are hormone producing (e.g., parathyroid, enteropancreatic endocrine, anterior pituitary) but some are not (e.g., angiofibroma). MEN1 tumors are multiple for organ type, for regions of a discontinuous organ, and for subregions of a continuous organ. Cancer contributes to late mortality; there is no effective prevention or cure for MEN1 cancers. Morbidities are more frequent from benign than malignant tumor, and both are indicators for screening. Onset age is usually earlier in a tumor type of MEN1 than of nonhereditary cases. Broad trends contrast with those in nonneoplastic excess of hormones (e.g., persistent hyperinsulinemic hypoglycemia of infancy). Most germline or somatic mutations in the MEN1 gene predict truncation or absence of encoded menin. Similarly, 11q13 loss of heterozygosity in tumors predicts inactivation of the other MEN1 copy. MEN1 somatic mutation is prevalent in nonhereditary, MEN1‐like tumor types. Compiled germline and somatic mutations show almost no genotype/phenotype relation. Normal menin is 67 kDa, widespread, and mainly nuclear. It may partner with junD, NF‐kB, PEM, SMAD3, RPA2, FANCD2, NM23β, nonmuscle myosin heavy chain II‐A, GFAP, and/or vimentin. These partners have not clarified menins pathways in normal or tumor tissues. Animal models have opened approaches to menin pathways. Local overexpression of menin in Drosophila reveals its interaction with the jun‐kinase pathway. The Men1+/− mouse has robust MEN1; its most important difference from human MEN1 is marked hyperplasia of pancreatic islets, a tumor precursor stage.


Cancer Gene Therapy | 2000

Vaccinia as a vector for tumor-directed gene therapy: Biodistribution of a thymidine kinase-deleted mutant

Markus Puhlmann; Charles K. Brown; Michael Gnant; James Huang; Steven K. Libutti; H. Richard Alexander; David L. Bartlett

Tumor-directed gene therapy, such as “suicide gene” therapy, requires high levels of gene expression in a high percentage of tumor cells in vivo to be effective. Current vector strategies have been ineffective in achieving these goals. This report introduces the attenuated (thymidine kinase (TK)-negative) replication-competent vaccinia virus (VV) as a potential vector for tumor-directed gene therapy by studying the biodistribution of VV in animal tumor models. A TK-deleted recombinant VV (Western Reserve strain) expressing luciferase on a synthetic promoter was constructed. Luciferase activity was measured in vitro after transduction of a variety of human and murine tumor cell lines and in vivo after intraperitoneal (i.p.) delivery in C57BL/6 mice with 7-day i.p. tumors (106 MC-38 cells). Three other in vivo tumor models were examined for tumor-specific gene expression after intravenous delivery of VV (human melanoma in nude mice, adenocarcinoma liver metastasis in immunocompetent mice, and subcutaneous sarcoma in the rat). In addition, a replication-incompetent vaccinia (1 μg of psoralen and ultraviolet light, 365 nm, 4 minutes) was tested in vitro and in vivo and compared with active virus. Luciferase activity in i.p. tumors at 4 days after i.p. injection of VV was >7000-fold higher than lung, >3000-fold higher than liver, and >250-fold higher than ovary. In addition, intravenous injection of VV resulted in markedly higher tumor luciferase activity compared with any other organ in every model tested (up to 188,000-fold higher than liver and 77,000-fold higher than lung). Inactivation of the virus resulted in negligible gene expression in vivo. In summary, VV has a high transduction efficiency in tumor cells with high levels of gene expression. The results suggest a selective in vivo replication of TK-deleted VV in tumor cells. Replication competent, TK-deleted VV appears to be an ideal vector for testing the in vivo delivery of toxic genes to tumor cells.


Annals of Surgical Oncology | 1999

Treatment of primary peritoneal mesothelioma by continuous hyperthermic peritoneal perfusion (CHPP)

Bernard J. Park; H. Richard Alexander; Steven K. Libutti; Peter Wu; Dan Royalty; Karen Kranda; David L. Bartlett

AbstractBackground: Primary peritoneal mesothelioma is a locally aggressive disease that is difficult to treat or even palliate. Continuous hyperthermic peritoneal perfusion (CHPP) with cisplatin (CDDP) allows uniform, high regional delivery of chemotherapeutics and hyperthermia to the peritoneal surface for the treatment of peritoneal tumors. This article summarizes the results of 18 patients with peritoneal mesothelioma treated with CHPP. Methods: From June 1993 through April 1998, 18 patients with primary peritoneal mesothelioma (13 male, 5 female; median age, 51 years) underwent surgical exploration and tumor debulking followed by a 90-minute CHPP with CDDP and hyperthermia as part of three consecutive phase I trials conducted at the National Cancer Institute. Seventeen of 18 patients had malignant peritoneal mesothelioma, 13 with associated ascites. One patient had a symptomatic, multiply recurrent, benign, cystic peritoneal mesothelioma. Three patients who had a recurrence after a prolonged progression-free interval (>6 months) after CHPP underwent re-treatment. CHPP parameters included median cisplatin dose of 530 mg (range, 187–816), perfusate volume 6.0 liter (range, 4–9), flow 1.5 liter/min (range, 1–2), intraperitoneal temperature 41°C (range, 38.7–43.2), and central temperature 38.6°C (range, 36.8–39.7). Results: Median follow-up after CHPP is 19 months (range, 2–56) with no operative or treatment-related mortality. Overall operative morbidity was 24% and included two patients with superficial wound infection and one patient each with atrial fibrillation, pancreatitis, fascial dehiscence, ileus, line sepsis, and clostridium difficile colitis. The major treatment-related toxicity was systemic renal toxicity at doses above what was defined as the maximum tolerated dose of cisplatin. Nine of 10 patients had resolution of their ascites postoperatively. Three patients who developed recurrent ascites (27, 22, and 10 months after initial treatment) were re-treated and had resolution of their ascites with ongoing responses at 24, 6, and 4 months after the second perfusion. The median progression-free survival was 26 months, and the overall 2-year survival was 80%. The median overall survival has not been reached. Conclusions: CHPP with cisplatin can be performed safely with no mortality and minimal morbidity. In selected patients, successful palliation in the abdomen and long-term survival, compared with historical controls, can be achieved with aggressive surgical debulking and CHPP. Re-treatment after initial response can result in a second long-term response.

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Steven K. Libutti

Albert Einstein College of Medicine

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Douglas L. Fraker

University of Pennsylvania

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Monica C. Skarulis

National Institutes of Health

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Stephen J. Marx

National Institutes of Health

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John L. Doppman

National Institutes of Health

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Nader Hanna

University of Maryland

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Robert T. Jensen

National Institutes of Health

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