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Biomedical subjects

E Hersh

Publications and source records attributed to E Hersh.

At least 19 recordsLinked to original sources

Gene delivery using ultrasound contrast agents.

With the human genome product and continuing advances in molecular biology many therapeutic genes have been discovered. In the cardiovascular system, gene therapy has the potential to improve myocardial vascularization and ameliorate congestive heart failure. For successful development of clinical gene therapy, however, effective gene delivery vectors are needed. Ultrasound contrast agents can be used to develop new, more effective vectors for gene delivery. Ultrasound contrast agents lower the threshold for cavitation by ultrasound energy. Using physical properties of microbubbles and coating materials, genetic drugs have been incorporated into ultrasound contrast agents. Gene-bearing microbubbles can be injected IV and ultrasound energy applied to the target region. As the microbubbles enter the region of insonation, the microbubbles cavitate, locally releasing DNA. Cavitation also likely causes a local shockwave that improves cellular uptake of DNA. With transthoracic ultrasound, using commercially available diagnostic ultrasound system and an IV injection of gene-bearing microbubbles, high levels of transgene expression are observed in the insonated region of the myocardium. This new technology using microbubbles and ultrasound for gene delivery merits further study and development.

Animals↗

Clinical aspects of intratumoral gene therapy.

One of the major obstacles to the development of gene therapy for cancer is our inability to deliver genes to all targets within the body. Thus, effective methodology does not exist to deliver a gene intravenously with the expectation that it will selectively localize within the target tumor, will not localize in other tissues and will be expressed efficiently. While one can take advantage of tissue-specific promoters to activate the gene only in a given target tissue, only a small fraction of the vector will be taken up in the target tissue and expressed. Consequently, since accessible local or regional tumor masses are a major problem in many cancers, there has been a strong emphasis on clinical trials in intratumoral and peritumoral gene delivery.

Adenoviruses, Human↗

Human gene therapy for melanoma: CT-guided interstitial injection.

OBJECTIVE: Our intent is to describe the role of CT in the intratumoral injection of Allovectin-7 (Vical, San Diego, CA), an allogeneic class I major histocompatibility complex antigen, HLA-B7, formulated with cationic lipid, in the treatment of metastatic malignant melanoma. MATERIALS AND METHODS: Ten patients with metastatic malignant melanoma were treated with gene therapy in which we used CT-guided intratumoral injection of plasmid DNA containing the HLA-B7 gene. This therapy was part of a phase I gene therapy trial in patients with metastatic melanoma. CT guidance was chosen as an accurate way to direct gene delivery in patients with deep, impalpable lesions. Tumor locations included pulmonary, mediastinal, hepatic, adrenal, and paracaval sites. Patients in the CT protocol underwent baseline CT studies. Examinations were repeated 2, 4, and 8 weeks after gene therapy and thereafter at 3-month intervals. Both injected and noninjected tumors were measured. CT-guided injections of 10, 50, or 250 micrograms of plasmid DNA were performed with 22-gauge spinal needles. Injection volumes were between 1.0 and 4.0 ml, depending on tumor size. CT-guided core biopsy specimens were obtained (with 18- or 20-gauge needles) from the selected tumor before therapy and 2, 4, and 8 weeks after therapy to assess HLA-B7 plasmid DNA and gene expression. Peripheral blood was analyzed for cytotoxic T lymphocytes directed against HLA-B7. RESULTS: CT-guided intratumoral injections were successful in delivering genetic material to all patients with impalpable tumors. Significant responses (as defined by a decrease of 25% or more in the product of the length and width of the injected tumor) were observed in six of the 10 patients. One of these six patients who had a solitary lesion remains free of disease 19 months after gene therapy. HLA-B7 protein expression was detected in 89% of biopsy specimens, and plasmid DNA and messenger RNA were detected in 56% and 22% of biopsy specimens, respectively. CONCLUSION: CT provides a safe, accurate, and efficacious way to monitor and assess tumor progression and response, and it provides guidance for biopsies and intratumoral injections during gene therapy. Significant responses in injected tumors of six of the 10 patients in our study suggest that further clinical trials of this gene therapy are warranted.

Adult↗

Phase 1 trial of recombinant human interleukin-1 beta (rhIL-1 beta), carboplatin, and etoposide in patients with solid cancers: Southwest Oncology, Group Study 8940.

Recombinant human interleukin-1 beta (rhIL-1 beta) was evaluated in a phase 1 clinical trial in which patients with metastatic or unresectable solid tumors received carboplatin and etoposide in cycle 1 and carboplatin, etoposide, and rhIL-1 beta in cycle 2. Recombinant hIL-1 beta was given intravenously for 5 days in one of three schedules: (1) immediately postchemotherapy, (2) delayed for 5 days after chemotherapy, or (3) concurrently with chemotherapy. Four dose levels of rhIL-1 beta were evaluated: 20, 50, 100, and 200 ng/kg. The doses of carboplatin and etoposide were not changed between cycle 1 and cycle 2 so that the effect of rhIL-1 beta on chemotherapy-induced hemato-toxicity was evaluated; 54 patients were entered on study and 42 patients received at least two cycles of therapy and were thus evaluable for rhIL-1 beta toxicity and for the effect of rhIL-1 beta on hematotoxicity of carboplatin and etoposide. The major toxicities of rhIL-1 beta were chills, rigors, headache, fatigue, and hypotension. The maximum tolerated dose of rhIL-1 beta was not determined since the toxicities at all dose levels were similar. However, only 3/8 patients at the 200 ng/kg level received all 5 IL-1 beta infusions. We compared the effect of rhIL-1 beta on hematotoxicity of carboplatin/etoposide by comparing peripheral blood count parameters between cycles 1 and 2: rhIL-1 beta given postchemotherapy significantly increased absolute neutrophil count (AND) nadirs and improved neutrophil recovery times regardless of rhIL-1 beta dose level. Platelet count parameters were also improved when rhIL-1 beta was given postchemotherapy although these changes did not reach statistical significance. Thus, IL-1 beta exhibited extensive hematological effects but the usefulness of this agent in clinical practice will be limited by extensive toxicity at all tested dose levels.

Adult↗

Inhibition of platelet-derived growth factor-mediated signal transduction and tumor growth by N-[4-(trifluoromethyl)-phenyl]5-methylisoxazole-4-carboxamide.

Many reports have cited coexpression of platelet-derived growth factor (PDGF) and its receptors by tumor cells or cells supporting tumor growth, suggesting both autocrine and paracrine mechanisms for PDGF-mediated tumor growth. We found that a small organic molecule, N-[4-(trifluoromethyl)phenyl] 5-methylisoxazole-4-carboxamide (SU101, leflunomide), inhibited PDGF-mediated signaling events, including receptor tyrosine phosphorylation, DNA synthesis, cell cycle progression, and cell proliferation. SU101 inhibited PDGF-stimulated tyrosine phosphorylation of PDGF receptor (PDGFR) beta in C6 (rat glioma) and NIH3T3 cells engineered to overexpress human PDGFRbeta (3T3-PDGFRbeta). SU101 blocked both PDGF- and epidermal growth factor (EGF)-stimulated DNA synthesis. Previously, this compound was shown to inhibit pyrimidine biosynthesis by interfering with the enzymatic activity of dihydroorotate dehydrogenase. In the current study, EGF-stimulated DNA synthesis was restored by the addition of saturating quantities of uridine, whereas PDGF-induced DNA synthesis was not, suggesting that the compound demonstrated some selectivity for the PDGFR pathway that was independent of pyrimidine biosynthesis. Selectivity was further demonstrated by the ability of the compound to block the entry of PDGF-stimulated cells into the S phase of the cell cycle, without affecting cell cycle progression of EGF-stimulated cells. In cell growth assays, SU101 selectively inhibited the growth of PDGFRbeta-expressing cell lines more efficiently than it inhibited the growth of PDGFRbeta-negative cell lines. SU101 inhibited the s.c., i.p., and intracerebral growth of a panel of cell lines including cells from glioma, ovarian, and prostate origin. In contrast, SU101 failed to inhibit the in vitro or s.c. growth of A431 and KB tumor cells, both of which express EGF receptor but not PDGFRbeta. SU101 also inhibited the growth of D1B and L1210 (murine leukemia) cells in syngeneic immunocompetent mice, without causing adverse effects on the immune response of the animals. In an i.p. model of tumor growth in syngeneic immunocompetent mice, SU101 prevented tumor growth and induced long-term survivors in animals implanted with 7TD1 (murine B-cell hybridoma) tumor cells. Because PDGFRbeta was detected on most of the tumor cell lines in which in vivo growth was inhibited by SU101, these data suggest that SU101 is an effective inhibitor of PDGF-driven tumor growth in vivo.

3T3 Cells↗

Phase I trial of recombinant interleukin 3 before and after carboplatin/etoposide chemotherapy in patients with solid tumors: a southwest oncology group study.

Recombinant human interleukin 3 (rhIL-3, expressed in Escherichia coli) is a hematopoietic growth factor with protean biological effects on bone marrow in animal models, including enhanced granulocyte and platelet production and the capacity to ameliorate chemotherapy-induced bone marrow toxicity. We, therefore, undertook a Phase I trial in patients with advanced solid tumors and normal bone marrow function. Cohorts of four to six patients each received daily s.c. doses of rhIL-3 (SDZ-ILE-964; Sandoz) at dose levels of 1. 0, 2.5, 5.0, and 10.0 microgram/kg according to the following schedule: cycle 1, rhIL-3 days 1-14; cycle 2, carboplatin (350 mg/m2) on day 1 and etoposide (100 mg/m2) on days 1-3; and cycle 3, carboplatin (350 mg/m2) on day 1, etoposide (100 mg/m2) on days 1-3, and rhIL-3 on days 4-17. Each cycle was a total of 28 days. An analysis of 20 patients entered into all four escalating dose levels revealed that, during cycle 1, absolute neutrophil count (ANC) increased from a median baseline of 6,643/mm3 to a median of 12,692/mm3, and platelets increased from a median baseline of 314,000/mm3 to a median of 465,000/mm3. When cycle 2 was compared with cycle 3, the median ANC nadir increased from 192/mm3 to 988/mm3, and the mean ANC nadir increased from 458/mm3 to 1,297/mm3. Median platelet count nadirs increased from 29,000/mm3 to 84,000/mm3, and the mean nadir platelet counts increased from 72,000/mm3 to 129,000/mm3. Total days on which platelets were <50,000/mm3 was 52 for cycle 2 and 19 for cycle 3. The maximum tolerated dose of rhIL-3 was 5.0 microgram/kg/day; dose-limiting toxicities included fatigue, chills, fever, and headache. These data suggest a clear but variable biological activity observed with IL-3, as measured by the reduction in the depth and duration of thrombocytopenia and/or neutropenia when cycle 2 was compared with cycle 3. rhIL-3 is a promising cytokine that may help to ameliorate the bone marrow toxicity observed with the use of chemotherapeutic agents.

Adult↗

Diethyldithiocarbamate, a novel immunomodulator, prolongs survival in autoimmune MRL-lpr/lpr mice.

MRL-lpr/lpr mice die at an early age from a spontaneously developing systemic lupus erythematosus-like disease and are characterized by massive lymphadenopathy, hyperproliferation of Lyt-2/L3T4 (null) T cells, decreased responses to mitogens, thymic atrophy, and very high serum autoantibody levels. Diethyldithiocarbamate (DTC), an immunomodulator suggested to enhance T cells, was used to treat 12-week-old female MRL-lpr/lpr mice (25 mg/kg/week). DTC treatment significantly prolonged survival (50% mortality, 43 weeks vs 20 weeks). Increased survival was associated with decreased lymphadenopathy, decreased proliferation of null cells, restoration of impaired mitogen responses, decreased thymic atrophy, and decreased serum levels of anti-DNA and anti-histone antibodies. Studies of cell surface antigen phenotype demonstrated increased expression of Lyt-2 and macrophage surface antigens. No effect on L3T4 single staining cells was observed. These results show that DTC significantly alters the disease course in these mice and suggest that DTC may be a useful treatment for autoimmune disease.

Adjuvants, Immunologic↗

Human monoclonal antibodies to the human immunodeficiency virus type 1 (HIV-1) transmembrane glycoprotein gp41 enhance HIV-1 infection in vitro.

Three of 16 human monoclonal antibodies (hu-mAbs) enhanced human immunodeficiency virus type 1 (HIV-1) infection of MT-2 target cells by means of a mechanism that is dependent on complement. Enhanced infections are characterized by an increase in cytopathic effects and antigen synthesis as well as an increase in the production of progeny virus as detected by release of reverse transcriptase activity and infectious virus into the culture medium. Analyses by radioimmunoprecipitation, Western blot, and ELISA using the pENV9 envelope fragment localize the antigenic specificities of these three hu-mAbs to the N-terminal two-thirds of the transmembrane protein gp41. Competitive binding experiments indicate that the hu-mAbs are reactive with immunodominant epitopes of gp41 recognized by sera from essentially all HIV-1-infected subjects. Combination dose-effect experiments demonstrate that these hu-mAbs can act synergistically in vitro to enhance HIV-1 infection. These data demonstrate that hu-mAbs directed against the HIV-1 transmembrane glycoprotein gp41 can enhance HIV-1 infection in vitro. The availability of these reagents allows for the mapping of enhancing epitopes on HIV-1 and provides a means for studying whether deletion of such enhancing epitopes from candidate HIV-1 vaccines might improve the protective immune response to HIV-1 in immunized humans and chimpanzees.

Antibodies, Monoclonal↗

Oxytocin during labor after previous cesarean section: results of a multicenter study.

The use of oxytocin for labor induction or augmentation in patients with previous cesarean delivery is controversial. This paper presents a series of 1776 patients allowed to labor after a previous cesarean section, of whom 485 (27%) were treated with oxytocin. When the patients who received oxytocin were compared with those who did not, no significant differences were found with respect to uterine rupture, maternal morbidity, fetal morbidity, or fetal mortality. We conclude that the judicious use of oxytocin is safe in the patient with a previous low transverse cesarean section.

Cesarean Section↗

Thymosin alpha 1 and thymosin beta 4 in serum: comparison of normal, cord, homosexual and AIDS serum.

Thymosin alpha 1 and thymosin beta 4 were first isolated from thymosin fr. 5 and have demonstrated biological activities on the immune system. They are chemically distinct and differ in their immunological activity profiles. The levels of thymosin alpha 1 and thymosin beta 4 were assessed by radioimmunoassay in the same serum samples. Normal thymosin alpha 1 levels were 670 +/- 163 pg/ml for males and 652 +/- 162 pg/ml for females. Normal thymosin beta 4 levels were 974 +/- 400 ng/ml for males and 889 +/- 345 ng/ml for females. No correlation between the levels of the peptides in serum from normal donors was observed. Although many samples of serum from neonates (cord blood), homosexuals and AIDS patients had elevated levels of one or both peptides, no correlation between the two peptides was found. Of potential significance is the observation that while thymosin alpha 1 and beta 4 are elevated in many individuals with AIDS (57 and 48% respectively), the individuals with AIDS related immune dysfunctions had predominantly elevated thymosin alpha 1 (54 vs 15%). These studies suggest that serum levels of the two peptides are modulated separately and that both are of potential value in defining the risk of individuals for developing AIDS.

Acquired Immunodeficiency Syndrome↗

Nonbacterial thrombotic endocarditis in a male homosexual with Kaposi's sarcoma.

Nonbacterial thrombotic endocarditis (NBTE), or marantic endocarditis, was found at autopsy in a young male homosexual with Kaposi's sarcoma. Vegetations were seen in the mitral and aortic valves. Embolic phenomena and cytomegalovirus infection were noted in the brain, spleen, liver, lung, gastrointestinal tract, and bone marrow. To our knowledge, this is the first reported case of NBTE in a young immunosuppressed homosexual man with Kaposi's sarcoma.

Adult↗

Phase I study of MVE-2 therapy in human cancer.

MVE-2, a polymer of maleic anhydride and divinyl-ether (molecular weight, 15,500), was given to 57 patients in a phase I study. The agent was selected for study because it was a potent macrophage activator, interferon inducer, and immunotherapeutic agent in animal tumor models. The drug was administered by iv infusion over a 1-hour period using three schedules of administration: (a) weekly at doses of 25-650 mg/m2, (b) every other week at doses of 500-1200 mg/m2, and (c) every 3 weeks at doses of 1200-1500 mg/m2. No cardiac, pulmonary, hematologic, or hepatic toxicity was observed. There were 25 episodes of asymptomatic proteinuria in 26 patients who received MVE-2 dose levels of greater than or equal to 500 mg/m2. It was not associated with changes in BUN or creatinine. The proteinuria began approximately 4 weeks after the start of therapy and lasted approximately 4-6 weeks after the therapy was terminated. Proteinuria resolved in all patients followed. At present, proteinuria appears to be the major dose-limiting toxicity. None of the patients had a partial or complete response although there was evidence of biologic activity with measurable tumor regression in five patients. No major modification of host defense parameters was noted. Further studies should be directed towards determining the nature of the proteinuria and whether changes in the rate or schedule of administration can modify the proteinuria or increase the host defense modification.

Blood Urea Nitrogen↗

Inflammatory breast cancer treated with surgery, chemotherapy and allogeneic tumor cell/BCG immunotherapy.

Thirteen consecutive patients with inflammatory breast cancer were treated with a regimen consisting of cyclic chemotherapy, extended simple mastectomy, and immunotherapy utilizing irradiated allogeneic breast cancer cells admixed with BCG. When surgery was performed after two or more cycles of 5-U, doxorubicin hydrochloride, and cyclophosphamide, there was complete eradication of detectable tumor in three of 11 operative specimens. Two patients had surgery prior to our evaluation and four had prior chemotherapy. Chest wall radiation was initiated after 8-10+ months of chemotherapy at the doxorubicin cardiotoxicity limits. Seven untreated patients, all premenopausal, were compared to our previous series which employed either irradiation after several courses of chemotherapy or irradiation alone. The current series has two relapses (eight months, 25 months) at a median follow-up time of 21 months (range, 8-26 months). In the previous chemoradiotherapy trial, all nine premenopausal patients had relapsed within 25 months, with a median disease free interval of 17 months. In the trial using radiotherapy alone, all ten patients had relapsed by 19 months (median disease free interval, nine months). The present regimen appears to improve control of the disease and further investigation of both surgery and immunotherapy intercalated with cyclic chemotherapy appears warranted in this disease.

Adult↗

Immunological studies in a double blind randomized trial comparing intrapleural BCG against placebo in patients with resected stage I non-small cell lung cancer.

Immunological data were obtained during the course of a randomized trial comparing intrapleural BCG plus oral isoniazid (INH) with intrapleural saline plus oral placebo after resection of stage I non-small cell lung cancer. Immunological testing with a variety of assays was carried out with good standardization among six collaborating laboratories and with good reproducibility within each laboratory. Those patients with larger tumors tended to have higher initial white cell counts. The percentage of lymphocytes in the differential was greatest in those with non-squamous cancer histology. Otherwise, no associations were found between initial immunologic parameters and baseline variables. The main effect of BCG/INH therapy was to cause statistically significant increases in purified protein derivative (PPD) skin test induration and PPD in vitro blastogenesis compared with controls. Other skin tests and in vitro assays increased more in the saline/placebo control group, but these treatment differences were usually not statistically significant. Initial white count and neutrophil count elevations were found to be associated with increased risk of recurrence. Even after adjustment for treatment and tumor stage, initial neutrophil count elevation was associated with increased risk of recurrence. Surprisingly, a low 29 degrees C T cell rosette index was associated with a decreased risk of recurrence, though the differences were minimal. Serial immunological tests were carried out to evaluate their potential for monitoring disease recurrence. White count elevations continued to be significantly associated with increased risk of recurrence, but more follow-up data are needed before other associations can be assessed.

BCG Vaccine↗

Factors related to length of complete remission in adult acute leukemia.

Two hundred and two adult patients with acute leukemia were analyzed to determine pretreatment and treatment factors that could predict for duration of bone marrow remission. Several factors had a significant effect on remission duration, including morphologic diagnosis (AML greater than ALL greater than AUL), initial blast cell count, age, serum LDH, fibrinogen level, labeling index, and in vitro agar colony growth. Patients who attained a remission quickly or in whom leukemic cells in blood and bone marrow were rapidly cleared had long remissions. After applying regression model fitting methods, the six major factors, in order of significance, were the initial serum LDH level, pretreatment fibrinogen level, the number of courses of treatment to obtain a remission, morphologic diagnosis, the halving rate of leukemic cells in the blood, and the age of the patient. The model derived from this study was applied to the 202 patients and suggested that patients likely to have short or long bone marrow remission can be identified.

Adolescent↗