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Biomedical subjects

Henry C Pitot

Publications and source records attributed to Henry C Pitot.

At least 19 recordsLinked to original sources
PubMed2006

Identification of biomarkers that distinguish human papillomavirus (HPV)-positive versus HPV-negative head and neck cancers in a mouse model.

Head and neck squamous cell carcinoma (HNSCC) is a leading cause of cancer mortality worldwide. Recent reports have associated a subset of HNSCC with high-risk human papillomaviruses (HPVs), particularly HPV16, the same subset of HPVs responsible for the majority of cervical and anogenital cancers. In this study we describe a mouse model for HPV-associated HNSCC that employs mice transgenic for the HPV16 oncogenes E6 and E7. In these mice, E6 and E7 induce aberrant epithelial proliferation and, in the presence of a chemical carcinogen, they increase dramatically the animal's susceptibility to HNSCC. The cancers arising in the HPV16-transgenic mice mirror the molecular and histopathological characteristics of human HPV-positive HNSCC that distinguish the latter from human HPV-negative HNSCC, including overexpression of p16 protein and formation of more basaloid cancers. This validated model of HPV-associated HNSCC provides the means to define the contributions of individual HPV oncogenes to HNSCC and to understand the molecular basis for the differing clinical properties of HPV-positive and HPV-negative human HNSCC. From this study, we identify minichromosome maintenance protein 7 (MCM7) and p16 as potentially useful biomarkers for HPV-positive head and neck cancer.

4-Nitroquinoline-1-oxide↗
PubMed2006

Randomized controlled trial of reduced-dose bolus fluorouracil plus leucovorin and irinotecan or infused fluorouracil plus leucovorin and oxaliplatin in patients with previously untreated metastatic colorectal cancer: a North American Intergroup Trial.

PURPOSE: Previously, we reported results of Intergroup N9741, which compared standard bolus fluorouracil (FU), leucovorin, plus irinotecan (IFL) with infused FU, leucovorin, plus oxaliplatin (FOLFOX4) and irinotecan plus oxaliplatin in patients with untreated metastatic colorectal cancer. High rates of grade > or = 3 toxicity on IFL (resulting in some deaths) led us to reduce the starting doses of both irinotecan and FU by 20% (rIFL). This article compares rIFL with FOLFOX4. PATIENTS AND METHODS: The primary comparison was time to progression, with secondary end points of response rate (RR), overall survival, and toxicity. RESULTS: Three hundred five patients were randomly assigned. The North Central Cancer Treatment Group Data Safety Monitoring Committee interrupted enrollment at a planned interim analysis when outcomes crossed predetermined stopping boundaries. The results were significantly superior for FOLFOX4 compared with rIFL for time to progression (9.7 v 5.5 months, respectively; P < .0001), RR (48% v 32%, respectively; P = .006), and overall survival (19.0 v 16.3 months, respectively; P = .026). Toxicity profiles were not significantly different between regimens for nausea, vomiting, diarrhea, febrile neutropenia, dehydration, or 60-day all-cause mortality. Sensory neuropathy and neutropenia were significantly more common with FOLFOX4. Approximately 75% of patients in both arms received second-line therapy; 58% of rIFL patients received oxaliplatin-based second-line therapy, and 55% of FOLFOX4 patients received irinotecan-based regimens as second-line therapy. CONCLUSION: FOLFOX4 led to superior RR, time to progression, and overall survival compared with rIFL. The survival benefit for FOLFOX4 observed in the earlier stage of the study was preserved with equal use of either irinotecan or oxaliplatin as second-line therapy.

Adult↗
PubMed2006

Phase II study of erlotinib in patients with advanced biliary cancer.

PURPOSE: Epidermal growth factor receptor/human epidermal growth factor receptor 1 and ligand expression is common in biliary cancers (BILI) and may be associated with worse outcome. The primary objective of this study was to determine the proportion of patients with advanced BILI who were progression-free at 6 months. METHODS: Patients with either unresectable or metastatic disease were studied. Only one prior systemic or locoregional therapy was allowed. Erlotinib was administered continuously at a dose of 150 mg per day orally. RESULTS: Forty-two patients with BILI were enrolled. The median age was 67 years (range, 33 to 82 years). Fifty-two percent of patients had Eastern Cooperative Oncology Group performance status of 1. Fifty-seven percent of patients had received prior chemotherapy for advanced BILI. HER1/EGFR expression by immunohistochemistry in tumor cells was detected in 29 (81%) of the 36 assessable patients. Seven of the patients (17%; 95% CI, 7% to 31%) were progression free at 6 months. Three patients had partial response by Response Evaluation Criteria in Solid Tumors Group classification of duration 4, 4, and 14 months, respectively. All responding patients had mild (grade 1/2) skin rash and two patients had positive tumoral HER1/EGFR expression. Three patients (7%) had toxicity-related dose reductions of erlotinib due to grade 2/3 skin rash. CONCLUSION: Results suggest a therapeutic benefit for EGFR blockade with erlotinib in patients with biliary cancer. Additional studies with erlotinib as a single agent and in combination with other targeted agents are warranted in this disease.

Adult↗
PubMed2006

A phase I and pharmacologic study of sequences of the proteasome inhibitor, bortezomib (PS-341, Velcade), in combination with paclitaxel and carboplatin in patients with advanced malignancies.

PURPOSE: Bortezomib, a selective inhibitor of the 20S proteasome with activity in a variety of cancers, exhibits sequence-dependent synergistic cytotoxicity with taxanes and platinum agents. Two different treatment schedules of bortezomib in combination with paclitaxel and carboplatin were tested in this phase I study to evaluate the effects of scheduling on toxicities, pharmacodynamics and clinical activity. METHODS: Patients with advanced malignancies were alternately assigned to receive (schedule A) paclitaxel and carboplatin (IV d1) followed by bortezomib (IV d2, d5, d8) or (schedule B) bortezomib (IV d1, d4, d8) followed by paclitaxel and carboplatin (IV d2) on a 21-day cycle. RESULTS: Fifty-three patients (A 25, B 28) were treated with a median of 3 cycles (range 1-8) for schedule A and 3.5 cycles (range 1-10) for schedule B. Grade 3 or higher treatment related hematologic adverse events in all cycles of treatment included neutropenia (A 52%, B 50%), anemia (A 12%, B 7.1%) and thrombocytopenia (A 16%, B 17.9%). Non-hematologic treatment related adverse events were fairly mild (primarily grades 1 and 2). The maximum tolerated dose and the recommended doses for future phase II trials are bortezomib 1.2 mg/m2, paclitaxel 135 mg/m2 and carboplatin AUC = 6 for schedule A and bortezomib 1.2 mg/m2, paclitaxel 175 mg/m2 and carboplatin AUC = 6 for schedule B. Six (21.4%) partial responses (PR) were seen with schedule B. In contrast, only 1 (4%) PR was achieved with schedule A. Similar proteasome inhibition was achieved at MTD for both schedules. CONCLUSION: Administration of sequential bortezomib followed by chemotherapy (schedule B) was well tolerated and associated with an encouraging number of objective responses in this small group of patients. Further studies with this administration schedule are warranted.

Adult↗
PubMed2006

Enzymatic and biochemical properties of a novel human serine dehydratase isoform.

A cDNA clone similar to human serine dehydratase (SDH) is deposited in the GenBank/EMBL databases, but its structural and functional bases remain unknown. Despite the occurrence of mRNA, the expected protein level was found to be low in cultured cells. To learn about physicochemical properties of the protein, we expressed the cDNA in Escherichia coli, and compared the expressed protein with that of a hepatic SDH. The purified protein showed l-serine and l-threonine dehydratase activity, demonstrating to be an isoform of SDH. However, their Km and Vmax constants were different in a range of two-order. Removal of Pro128 from the hepatic SDH consisting of 328 residues, which is missing in the corresponding position of the isoform consisting of 329 residues, significantly changed the Michaelis constants and Kd value for pyridoxal 5'-phosphate, whereas addition of a proline residue to the isoform was without effect. These findings suggest the difference in the structures of the active sites of the two enzymes. Another striking feature was that the expressed level of the isoform in E. coli was 7-fold lower than that of the hepatic SDH. Substitution of Val for Leu287 in the isoform dramatically increased the protein level. The high yield of the mutated isoform was also confirmed by the in vitro transcription and translation experiment. The poor expression of the isoform could be explained by the more stable secondary structure of the mRNA than that of the hepatic SDH mRNA. The present findings may provide a clue as to why the protein level in cultured cells is low.

Amino Acid Sequence↗
PubMed2006

A software package to improve image quality and isolation of objects of interest for quantitative stereology studies of rat hepatocarcinogenesis.

In the studies of quantitative stereology of rat hepatocarcinogenesis, we have used image analysis technology (automatic particle analysis) to obtain data such as liver tissue area, size and location of altered hepatic focal lesions (AHF), and nuclei counts. These data are then used for three-dimensional estimation of AHF occurrence and nuclear labeling index analysis. These are important parameters for quantitative studies of carcinogenesis, for screening and classifying carcinogens, and for risk estimation. To take such measurements, structures or cells of interest should be separated from the other components based on the difference of color and density. Common background problems seen on the captured sample image such as uneven light illumination or color shading can cause severe problems in the measurement. Two application programs (BK_Correction and Pixel_Separator) have been developed to solve these problems. With BK_Correction, common background problems such as incorrect color temperature setting, color shading, and uneven light illumination background, can be corrected. With Pixel_Separator different types of objects can be separated from each other in relation to their color, such as seen with different colors in immunohistochemically stained slides. The resultant images of such objects separated from other components are then ready for particle analysis. Objects that have the same darkness but different colors can be accurately differentiated in a grayscale image analysis system after application of these programs.

Animals↗
PubMed2006

Combination of paclitaxel and carboplatin as second-line therapy for patients with metastatic melanoma.

BACKGROUND: Patients with metastatic melanoma (MM) have very few therapy options. Based on reports of responses to paclitaxel and carboplatin (PC), 31 patients with MM were treated with PC. METHODS: Data regarding patients treated with PC were abstracted from medical records. Clinical outcomes as determined by the treating oncologist were used for this analysis. Response determination was retrospectively confirmed using Response Evaluation Criteria in Solid Tumors (RECIST). RESULTS: Thirty-one patients with MM were treated with PC. Patients had a median of 2 previous therapies, with the majority (29; 94%) having failed prior temozolomide (TMZ) or dacarbazine (DTIC) therapy. The most commonly used regimen was weekly paclitaxel (at a dose of 100 mg/m(2)) and carboplatin (area under the curve 2) administered on Days 1, 8, and 15 of a 28-day cycle. An objective partial response was noted in 8 patients (26%) with an additional 6 patients (19%) having stable disease; therefore, a clinical benefit was noted in 45% of those patients treated. The median time to disease progression for the entire group was 3 months (range, 0-7 mos), with a median overall survival of 7.8 months (range, 1-14 mos). The clinical benefit derived by the 14 patients, which lasted for a median of 5.7 months (range, 2.5-7.3 mos), was considered to be clinically significant. At the time of last follow-up, eight patients continued to receive PC therapy. CONCLUSIONS: The PC combination appears to have definite and clinically meaningful activity when used as second-line therapy after TMZ or DTIC. Further evaluation of this regimen, alone or as a 'backbone' for other agents, needs to be considered.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2006

Peptide vaccination of patients with metastatic melanoma: improved clinical outcome in patients demonstrating effective immunization.

OBJECTIVES: Therapeutic peptide vaccines for melanoma continue to only demonstrate anecdotal success. We set out to evaluate the impact of low-dose GM-CSF emulsified in Montanide ISA-51 on the immunogenicity of HLA-A2 restricted melanoma differentiation antigen peptide vaccines (MART-1, gp100 and tyrosinase) administered in separate subcutaneous injections. METHODS: We conducted a randomized phase II clinical trial of HLA-A2+ patients with metastatic melanoma that were immunized every 3 weeks with one of the following vaccine preparations: (A) peptides + Montanide ISA-51; (B) peptides + Montanide ISA-51 + GM-CSF (10 microg); (C) peptides + Montanide ISA-51 + GM-CSF (50 microg). Immunization efficacy was determined by quantification of vaccine specific tetramer positive cytotoxic T cells in peripheral blood. Global assessment of immune competence was ascertained using DTH testing to common recall antigens as well as peripheral blood immunophenotyping. RESULTS: Twenty-five eligible patients were equally distributed across all 3 treatment groups. Only 9 patients demonstrated evidence of immunization. Most commonly, immune response was achieved to the gp100 peptide. The addition of low-dose GM-CSF did not impact immunization efficacy. DTH reactivity to Candida appeared predictive of successful immunization. Successful immunization with the peptide vaccines was associated with improved clinical outcomes. CONCLUSIONS: The addition of low dose GM-CSF to peptide vaccines did not enhance immunogenicity. Higher doses of GM-CSF may be needed to achieve this effect and this is a testable hypothesis. Likewise, better patient selection based on immunologic status (DTH reactivity) may be helpful to better understand the clinical impact of therapeutic cancer vaccines.

Adjuvants, Immunologic↗
PubMed2005

A phase I and pharmacokinetic study of a powder-filled capsule formulation of oral irinotecan (CPT-11) given daily for 5 days every 3 weeks in patients with advanced solid tumors.

PURPOSE: Intravenous (i.v.) irinotecan is a cytotoxic topoisomerase I inhibitor with broad clinical activity in metastatic colorectal cancer and other tumors. The development of an oral formulation of irinotecan could enhance convenience and lessen the expense of palliative irinotecan delivery. This phase I study evaluated the dose-limiting toxicities (DLT), maximum tolerated dose (MTD), and pharmacokinetics (PK) of irinotecan given as a powder-filled capsule (PFC) daily for 5 days every 3 weeks. PATIENTS AND METHODS: Patients with advanced solid tumors received escalating doses of oral irinotecan daily for 5 days every 3 weeks. Plasma samples were collected following the first and fifth doses of irinotecan during Cycle 1 to determine the PK of irinotecan and its major circulating metabolites: SN-38, SN-38G, and APC. RESULTS: 20 patients (median age 61.5 years, range 40-75; M/F 12/8; ECOG PS 0=5, 1=11, 2=4) received oral irinotecan at dose levels of 30 (n=3), 40 (n=3), 50 (n=6), and 60 (n=8) mg/m(2)/day. Of the eight patients enrolled at 60 mg/m(2), three patients experienced DLT (> or = grade 3) consisting of nausea (three patients), vomiting (three patients), diarrhea (two patients), and febrile neutropenia (two patients) for which all the three patients required hospitalization. Treatment of six patients at the 50-mg/m(2) dose level resulted in no DLT. Other toxicities observed include abdominal pain, alopecia, anorexia, and asthenia. After oral administration, irinotecan was rapidly absorbed into systemic circulation and converted to the active metabolite SN-38. Increasing dose levels resulted in a dose-dependent increase in mean exposure parameters (Cmax and AUC) of irinotecan and metabolites. Systemic exposure parameters (Cmax and AUC(0-24)) of irinotecan and SN-38 were comparable between days 1 and 5. The extent of conversion from irinotecan to SN-38 was approximately threefold higher after the oral administration compared to that previously observed after i.v. administration. The exposure parameters of irinotecan or SN-38 are of limited value in predicting severity of Cycle 1 toxicities in the twofold dose range evaluated. CONCLUSION: Daily oral administration of irinotecan as the PFC formulation for 5 days every 3 weeks can safely deliver protracted exposure to SN-38, with the MTD of 50 mg/m(2)/d.

Administration, Oral↗
PubMed2005

Phase II study of Erlotinib (OSI-774) in patients with advanced hepatocellular cancer.

PURPOSE: Epidermal growth factor receptor/human epidermal growth factor receptor 1 (EGFR/HER1) and ligand expression is frequently seen in hepatocellular cancers (HCCs). Erlotinib (Tarceva, OSI-774; OSI Pharmaceuticals, Melville, NY) is a receptor tyrosine kinase inhibitor with specificity for the EGFR/HER1. METHODS: The primary objective of this study was to determine the proportion of patients with advanced HCC who were progression-free at 6 months. Patients with either unresectable or metastatic disease were studied. Only one prior systemic or locoregional therapy was allowed. Erlotinib was given continuously at a dose of 150 mg per day orally. RESULTS: Thirty-eight patients with HCC were enrolled. Median age of the patients was 69 years (range, 27 to 83 years). A majority of patients (63%) had an Eastern Cooperative Oncology Group performance status of 1. Forty-seven percent of patients had received prior chemotherapy for advanced HCC. EGFR/HER1 expression was detected in 88% of the patients. Median number of cycles per patient was two (range, 1 to 26). Twelve (32%; CI 95%, 18 to 49) of the 38 patients with HCC were progression-free at 6 months. Three patients had partial radiologic responses of duration of 2, 10, and 11 months, respectively. Disease control was seen in 59% of the patients. Median overall survival time was 13 months. Ten patients (26%) had toxicity-related dose reductions of erlotinib. Grade 3/4 skin toxicity or diarrhea was encountered in five and three patients, respectively. CONCLUSION: Results of this trial suggest a benefit for EGFR/HER1 blockade with erlotinib in patients with HCC manifested by disease control. Additional studies with erlotinib as a single agent or in combination with other agents are warranted.

Administration, Oral↗
PubMed2005

A phase I and pharmacologic trial of two schedules of the proteasome inhibitor, PS-341 (bortezomib, velcade), in patients with advanced cancer.

PURPOSE: To define the toxicities, pharmacodynamics, and clinical activity of the proteasome inhibitor, PS-341 (bortezomib), in patients with advanced malignancies. PATIENTS AND METHODS: Twenty-eight patients (14 male and 14 female) received PS-341 twice weekly for 4 of 6 weeks (schedule I). Because toxicity necessitated dose omissions on this schedule, 16 additional patients (12 male and 4 female) received PS-341 twice weekly for 2 of every 3 weeks (schedule II). A total of 73 courses of treatment was given (median, 2; range, 1-4). Inhibition of 20S proteasome activity in peripheral blood mononuclear cells (PBMC) and accumulation of proteasome-targeted polypeptides in tumor tissue were evaluated as pharmacodynamic markers of PS-341 activity. RESULTS: The most common toxicity was thrombocytopenia, which was dose limiting at 1.7 mg/m2 (schedule I) and 1.6 mg/m2 (schedule II), respectively. Sensory neuropathy was dose-limiting in a patient in schedule I. Grade > or =3 toxicities for schedule I were constipation, fatigue, myalgia, and sensory neuropathy. Grade > or =3 toxicities for schedule II were dehydration resulting from diarrhea, nausea and vomiting, fatigue, hypoglycemia, and hypotension. The maximum tolerated dose was 1.5 mg/m2 for both schedules. Reversible dose-dependent decreases in 20S proteasome activity in PBMCs were observed, with 36% inhibition at 0.5 mg/m2, 52% at 0.9 mg/m2, and 75% at 1.25 mg/m2. Accumulation of proteasome-targeted polypeptides was detected in tumor samples after treatment with PS-341. A patient with multiple myeloma had a partial response. CONCLUSION: PS-341 given 1.5 mg/m2 twice weekly for 2 of every 3 weeks is well tolerated and should be further studied.

Adult↗
PubMed2005

A phase IB study of the pharmacokinetics of gemcitabine and pemetrexed, when administered in rapid sequence to patients with advanced solid tumors.

BACKGROUND: We have previously demonstrated that pemetrexed is clinically active when administered 90 min after gemcitabine in a phase I study. The present study was undertaken to evaluate the efficacy, toxicity, and pharmacokinetics of gemcitabine and pemetrexed when pemetrexed is administered immediately after gemcitabine. PATIENTS AND METHODS: A total of 14 patients received 84 cycles of treatment. Gemcitabine 1250 mg/m(2) was administered on days 1 and 8 of each 21-day cycle, and pemetrexed 500 mg/m(2) on day 8 immediately following gemcitabine administration. Toxicities were graded according to the National Cancer Institute Common Toxicity Criteria and recorded as maximum grade per patient for all treatment cycles. Pharmacokinetic analyses of plasma gemcitabine and pemetrexed concentrations were performed. RESULTS: Neutropenia was the most common severe toxicity. Non-hematologic toxicities, which included nausea, vomiting, fatigue, diarrhea, rash, and elevated transaminases were of mild-to-moderate severity. No increased toxicity was observed with this schedule in comparison to the previous phase I schedule. There was no pharmacokinetic interaction between the two drugs. One partial response was documented in a patient with non-small-cell lung cancer. Eight patients had disease stabilization for five or more cycles. CONCLUSION: Gemcitabine immediately followed by pemetrexed is well tolerated and clinically active, and deserves further evaluation in phase II trials.

Adult↗
PubMed2005

A phase I trial of the novel farnesyl protein transferase inhibitor, BMS-214662, in combination with paclitaxel and carboplatin in patients with advanced cancer.

PURPOSE: This phase I study was conducted to determine the toxicities, pharmacokinetics, and pharmacodynamics of BMS-214662, a farnesyl transferase inhibitor, in combination with paclitaxel and carboplatin, in patients with advanced solid tumors. EXPERIMENTAL DESIGN: Patients with solid tumors received one of six escalating dose levels of BMS-214662 infused over 1 hour given following paclitaxel and carboplatin on the first day of a 21-day cycle. Toxicities were graded by the National Cancer Institute common toxicity criteria and recorded as maximum grade per patient for each treatment cycle. Inhibition of farnesyl transferase activity in peripheral blood mononuclear cells (PBMCs) was evaluated. Accumulation of unfarnesylated HDJ-2 in PBMCs of patients was evaluated as a marker of farnesyl transferase inhibition by BMS-214662. RESULTS: Thirty patients received 141 cycles of treatment through six dose levels. Dose-limiting toxicities were neutropenia, thrombocytopenia, nausea, and vomiting. There was no pharmacokinetic interaction between BMS-214662 and paclitaxel. The maximum tolerated dose was established as BMS-214662 (160 mg/m(2)), paclitaxel (225 mg/m(2)) and carboplatin (area under the curve = 6 on day 1), every 21 days. Inhibition of HDJ-2 farnesylation in PBMCs of patients was shown. One measurable partial response was observed in a patient with taxane-resistant esophageal cancer. There was partial regression of evaluable disease in two other patients (endometrial and ovarian cancer). Stable disease (> 4 cycles) occurred in eight other patients. CONCLUSIONS: The combination of BMS-214662 with paclitaxel and carboplatin was well tolerated, with broad activity in solid tumors. There was no correlation between dose level and accumulation of unfarnesylated HDJ-2 in PBMCs nor tumor response.

Adult↗
PubMed2005

Some biochemical and histochemical properties of human liver serine dehydratase.

In rat, serine dehydratase (SDH) is abundant in the liver and known to be a gluconeogenic enzyme, while there is little information about the biochemical property of human liver serine dehydratase because of its low content and difficulty in obtaining fresh materials. To circumvent these problems, we purified recombinant enzyme from Escherichia coli, and compared some properties between human and rat liver serine dehydratases. Edman degradation showed that the N-terminal sequence of about 75% of human serine dehydratase starts from MetSTART-Met2-Ser3- and the rest from Ser3-, whereas the N-terminus of rat enzyme begins from the second codon of MetSTART-Ala2-. The heterogeneity of the purified preparation was totally confirmed by mass spectrometry. Accordingly, this observation in part fails to follow the general rule that the first Met is not removed when the side chain of the penultimate amino acid is bulky such as Met, Arg, Lys, etc. There existed the obvious differences in the local structures between the two enzymes as revealed by limited-proteolysis experiments using trypsin and Staphylococcus aureus V8 protease. The most prominent difference was found histochemically: expression of rat liver serine dehydratase is confined to the periportal region in which many enzymes involved in gluconeogenesis and urea cycle are known to coexist, whereas human liver serine dehydratase resides predominantly in the perivenous region. These findings provide an additional support to the previous notion suggested by physiological experiments that contribution of serine dehydratase to gluconeogenesis is negligible or little in human liver.

Amino Acid Sequence↗
PubMed2004

The aryl hydrocarbon receptor is required for developmental closure of the ductus venosus in the neonatal mouse.

A developmental role for the Ahr locus has been indicated by the observation that mice harboring a null allele display a portocaval vascular shunt throughout life. To define the ontogeny and determine the identity of this shunt, we developed a visualization approach in which three-dimensional (3D) images of the developing liver vasculature are generated from serial sections. Applying this 3D visualization approach at multiple developmental times allowed us to demonstrate that the portocaval shunt observed in Ahr-null mice is the remnant of an embryonic structure and is not acquired after birth. We observed that the shunt is found in late-stage wild-type embryos but closes during the first 48 h of postnatal life. In contrast, the same structure fails to close in Ahr-null mice and remains open throughout adulthood. The ontogeny of this shunt, along with its 3D position, allowed us to conclude that this shunt is a patent developmental structure known as the ductus venosus (DV). Upon searching for a physiological cause of the patent DV, we observed that during the first 48 h, most major hepatic veins, such as the portal and umbilical veins, normally decrease in diameter but do not change in Ahr-null mice. This observation suggests that failure of the DV to close may be the consequence of increased blood pressure or a failure in vasoconstriction in the developing liver.

Animals↗
PubMed2004

Intratumoral administration of a 1,2-dimyristyloxypropyl-3- dimethylhydroxyethyl ammonium bromide/dioleoylphosphatidylethanolamine formulation of the human interleukin-2 gene in the treatment of metastatic renal cell carcinoma.

BACKGROUND: Leuvectin (Vical Inc., San Diego, CA) is a gene transfer product in which a plasmid encoding the human interleukin-2 (IL-2) gene is complexed with the cationic lipid 1,2-dimyristyloxypropyl-3-dimethylhydroxyethyl ammonium bromide/dioleoylphosphatidylethanolamine (DMRIE/DOPE). In the current study, the authors investigated the safety and efficacy of in situ vaccination with Leuvectin in patients with metastatic renal cell carcinoma. METHODS: Thirty-one patients with metastatic renal cell carcinoma were treated with intratumorally administered Leuvectin at doses ranging from 0.75 to 4 mg. These patients subsequently were evaluated for response and for treatment-related toxicity. RESULTS: Treatment was well tolerated: no Grade 3 or 4 toxicities were observed in association with the study agent. Documented side effects included Grade 1 pain at the injection site (20%); mild (i.e., Grade 1 or 2) constitutional symptoms, including malaise/myalgia, low-grade fever, and chills (74%); Grade 1 fatigue (19%); Grade 1 or 2 nausea (10%); and Grade 2 allergy (1 occurrence). Two patients experienced partial responses, which endured for 32 months and 6 years, respectively, and 1 patient currently is experiencing a pathologic complete response, which, to date, has persisted for 50 months; thus, the overall response rate was 10%. In addition, 7 patients (23%) experienced disease stabilization for a median of 8 months (range, 4-48 months). The median duration of survival from the start of Leuvectin treatment was 11 months (range, 2-72 months), with a 1-year survival rate of 48% and a 3-year survival rate of 19%. Laboratory analysis of tumor samples revealed the presence of IL-2 plasmid DNA in six of eight patients posttreatment, increased IL-2 expression in tumor cells in four of eight patients posttreatment, and increased tumor infiltration by CD8-positive lymphocytes in five of eight patients posttreatment. CONCLUSIONS: Immunotherapy with intratumorally administered Leuvectin is safe and can lead to durable objective responses in patients with metastatic renal cell carcinoma.

Adult↗