Biomedical subjects
Publications and source records attributed to M J Hawkins.
The association of HIV risk-taking behavior with frequency of depressive symptoms varied by specific risk behavior and amount of harm reduction of behavior of men and women (N = 642), 80% of whom were African-American.
Interferon-alpha (IFN-alpha) therapy is frequently associated with significant fatigue, which is often the dominant dose-limiting side effect. The fatigue associated with IFN-alpha therapy is usually dose related, worsens with continued therapy, and is associated with significant depression. Although the direct cause of IFN-alpha-induced fatigue is unknown, it is possible that neuromuscular fatigue, similar to that observed in patients with postpolio syndrome, is one component of this syndrome. The induction of proinflammatory cytokines observed in patients treated with IFN-alpha is consistent with a possible mechanism of neuromuscular pathology that could manifest as fatigue. Further research using established techniques for the study of neuromuscular fatigue is needed to test this hypothesis. Understanding the etiology of IFN-alpha-induced fatigue is the first step toward developing effective therapeutic interventions. Nonpharmacologic interventions for fatigue have begun to be seriously evaluated in cancer patients and patients receiving IFN-alpha therapy. Pharmacologic interventions for neuromuscular fatigue also are being investigated.
9-cis-Retinoic acid (9-cis-RA) and all-trans-RA (ATRA) are naturally occurring hormones. The nuclear receptors that mediate the effects of retinoids are the retinoic acid receptors (RARs) and the retinoid X receptors (RXRs). ATRA binds RAR with high affinity but does not bind to RXR, whereas 9-cis-RA, an isomer of ATRA, is a ligand that binds and transactivates both RARs and RXRs. The goals of this study were to determine the safety, tolerability, pharmacokinetics, and metabolic profile of 9-cis-RA in advanced cancer patients. Forty-one patients received oral 9-cis-RA (ALRT1057; Panretin capsules) at doses ranging from 5-140 mg/m2/day. Twenty-six patients were treated once daily with up to 140 mg/m2; a subsequent cohort of 15 patients were treated twice daily (b.i.d.) at 100-140 mg/m2/day (50, 60, and 70 mg/m2 b.i.d.) to evaluate a b.i.d. dosing regimen. Headache was the most frequent adverse event and was dose limiting in 3 of 41 patients. Skin toxicity was the next most common toxicity and was seen in 11 of 41 patients; it was typically mild and limited to skin dryness and erythema. Other toxicities included conjunctivitis, flushing, diarrhea, transaminitis, hypercalcemia, and asymptomatic hypertryglyceridemia. Toxicities were typically dose related, occurred primarily above 83 mg/m2/day, and were not ameliorated by b.i.d. dosing. No tumor responses were observed. The mean day 1 area under the plasma concentration-time curve and peak plasma concentration values were dose-proportional over all dose levels, whereas day 15 area under the plasma concentration-time curve and peak plasma concentration values were nonlinear above 83 mg/m2/day, suggesting that 9-cis-RA induced its own metabolism at doses equal to and above 140 mg/m2/day. 9-cis-RA is a retinoid receptor pan agonist with a more favorable pharmacokinetic and toxicity profile than that observed with previously studied retinoids and merits further investigation.
The matrix metalloproteinases (MMPs) are a family of at least fifteen secreted and membrane-bound zinc-endopeptidases. Collectively, these enzymes can degrade all of the components of the extracellular matrix, including fibrallar and non-fibrallar collagens, fibronectin, laminin and basement membrane glycoproteins. MMPs are thought to be essential for the diverse invasive processes of angiogenesis and tumor metastasis. Numerous studies have shown that there is a close association between expression of various members of the MMP family by tumors and their proliferative and invasive behavior and metastatic potential. In some of human cancers a positive correlation has also been demonstrated between the intensity of new blood vessel growth (angiogenesis) and the likelihood of developing metastases. Thus, control of MMP activity in these two different contexts has generated considerable interest as a possible therapeutic target. The tissue inhibitors of metalloproteinases (TIMPs) are naturally occurring proteins that specifically inhibit matrix metalloproteinases, thus maintaining balance between matrix destruction and formation. An imbalance between MMPs and the associated TIMPs may play a significant role in the invasive phenotype of malignant tumors. TIMP-1 has been shown to inhibit tumor-induced angiogenesis in experimental systems. These findings raised the possibility of using an agent that affects expression or activity of MMPs as an anti-cancer therapy. TIMPs are probably not suitable for pharmacologic applications due to their short half-life in vivo. Batimastat (BB-94) and marimastat (BB-2516) are synthetic, low-molecular weight MMP inhibitors. They have a collagen-mimicking hydroxamate structure, which facilitates chelation of the zinc ion in the active site of the MMPs. These compounds inhibit MMPs potently and specifically. Batimastat was the first synthetic MMP inhibitor studied in humans with advanced malignancies, but its usefulness has been limited by extremely poor water solubility, which required intraperitoneal administration of the drug as a detergent emulsion. Marimastat belongs to a second generation of MMP inhibitors. In contrast to batimastat, marimastat is orally available. Both of these agents are currently in Phase I/II trials in US, Europe and Canada. Some other new agents, currently in clinical trials, have been shown to inhibit MMP production. Bryostatins, naturally occurring macrocyclic lactones, have both in vitro and in vivo activity in numerous murine and human tumors. In culture, bryostatin-1 has been shown to induce differentiation and halt the growth of several malignant cell lines. While the exact mechanism responsible for anti-tumor activity is unclear, an initial event in the action of bryostatin-1 is activation of protein kinase C (PKC), followed by its down regulation. Bryostatin-1 does not directly affect the activity of MMPs, but it can inhibit the production of MMP-1, 3, 9, 10 and 11 by inhibiting PKC. TIMP-1 levels could also be modulated by bryostatin-1, as it is encoded by a PKC responsive gene.
Tumor angiogenesis is critically important to tumor growth and metastasis. We have shown that pentosan polysulfate (PPS) is an effective inhibitor of heparin-binding growth factors in vitro and can effectively inhibit the establishment and growth of tumors in nude mice. Following completion of our Phase I trial of s.c. administered PPS, we performed a Phase I trial of p.o. administered PPS in patients with advanced cancer to determine the maximum tolerated dose (MTD) and toxicity profile and to search for any evidence for biological activity in vivo. Patients diagnosed with advanced, incurable malignancies who met standard Phase I criteria and who did not have a history of bleeding complications were enrolled, in cohorts of three, to receive PPS p.o. t.i.d., at planned doses of 180, 270, 400, 600, and 800 mg/m2. Patients were monitored at least every 2 weeks with physical exams and weekly with hematological, chemistry, stool hemoccult, and coagulation blood studies, and serum and urine samples for PPS and basic fibroblastic growth factor (bFGF) levels were also taken. The PPS dose was escalated in an attempt to reach the MTD. Eight additional patients were enrolled at the highest dose to further characterize the toxicity profile and biological in vivo effects of PPS. A total of 21 patients were enrolled in the three cohorts of doses 180 (n = 4), 270 (n = 3), and 400 (n = 14) mg/m2. The most severe toxicities seen were grade 3 proctitis and grade 4 diarrhea; however, 20 of the 21 patients had evidence of grade 1 or 2 gastrointestinal (GI) bleeding. These toxicities became evident at a much earlier time point as the dose was increased, but their severities were similar at all dose levels. There were no objective responses, although three patients had prolonged stabilization of previously progressing disease. Pharmacokinetic analysis suggested marked accumulation of PPS upon chronic administration. Serum and urine bFGF levels failed to show a consistent, interpretable pattern; however the data suggested an inverse relationship between PPS and bFGF levels in vivo. A MTD could not be determined using the daily t.i.d. dosing schedule due to the development of grade 3/4 GI toxicity (proctitis) at all dose levels studied. PPS, administered p.o. at doses of 400 mg/m2 t.i.d., did not cause significant systemic toxicity, but most patients developed moderate-to-severe GI toxicity within 1-2 months. The cause of the GI toxicity was unclear, but it was readily reversible upon cessation of the agent. The suggestion of an inverse relationship between PPS and bFGF supports further study of PPS as an antiangiogenic agent. The tested doses and schedule cannot be recommended for further study. Subsequent murine experiments showed PPS to be more effective as an anticancer agent when it is given intermittently. We propose a study of PPS given on a weekly schedule in further clinical trials.
Degradation of basement membrane and extracellular matrix by matrix metalloproteinases (MMPs) is believed to be required for tumor invasion, tumor-induced angiogenesis and vascular invasion. A synthetic hydroxamate, batimastat (also known as BB-94), inhibits MMPs by binding the zinc ion in the active site of the MMP. Batimastat inhibits at least 50% of MMP activity at concentrations less than or equal to 10 ng/ml in vitro. Batimastat retarded ascites accumulation and increased survival in mice with human ovarian tumor xenografts. Acute and long-term toxicological studies revealed no major toxicity in animals. Batimastat is poorly soluble and was administered intraperitoneally (i.p.) as a suspension. Previous studies in patients with malignant ascites have shown no major toxicities at doses as high as 1350 mg/m2.
Antiangiogenic agents have been recently recognized to be potentially useful in the treatment of malignant processes. There has been a resulting flood of these agents into the clinical research field, forcing researchers to consider the unique problems which these agents pose. As these are agents with a novel, angiostatic mechanism of action, new clinical trial designs may become necessary to move these agents from the phase 1 level on to clinical use. Currently, several of these agents are being or have been tested in clinical trials. In this article, we review the available clinical data with antiangiogenic agents from other investigators, and our own experience with pentosan polysulfate.
Complete inhibition of angiogenesis should be well tolerated in most adults because under physiologic conditions angiogenesis is required only for wound healing and reproduction. However, angiogenesis is required for malignant solid tumor growth beyond 1 to 2 cubic millimeters, and microvessel counts in tumor specimens have been correlated with prognosis in patients with malignancies of the breast, prostate, and central nervous system. Antiangiogenic agents that bind to heparin-binding growth factors, inactivate matrix metalloproteinases, or inhibit endothelial cell proliferation are currently being tested as single agents in clinical trials. Recombinant proteins such as interferon alfa and platelet factor 4 may also have antiangiogenic activity through mechanisms that are not yet completely defined. Because they act through diverse mechanisms of action, antiangiogenic agents may achieve maximum biologic effect when administered together. These agents are particularly attractive in the surgical adjuvant setting because the risk for development of drug resistance and induction of second malignancies is low.
Patients (n = 22) with metastatic or unresectable colorectal carcinoma were treated with interleukin (IL)-2 and lymphokine-activated killer (LAK) cells in a phase II study conducted by the IL-2/LAK Working Group (ILWG). Eligibility criteria for the study included bi-dimensionally measurable disease, performance status 0 or 1, and normal function of all vital organs. The median age of patients was 49 (range, 28-61) years. Eight (36%) patients had never received prior treatment other than their initial surgery; eight (36%) had received prior radiotherapy, and 12 (55%) chemotherapy. No patients had received prior immunotherapy. Treatment consisted of IL-2, 600,000 IU/kg administered by 15-min intravenous infusion every 8 h on days 1-5 and 12-16. Patients underwent 4-h leukapheresis on days 8-12, and cells were placed in in vitro culture with IL-2 for 3-4 days and the activated LAK cells were infused over 1 h on days 12, 13, and 15. All doses of IL-2 and LAK cells were administered to patients in intensive care unit (ICU) settings. The mean +/- SD number of IL-2 doses administered during days 1-5 was 13.4 +/- 1.2, the mean number of LAK cells reinfused was 6.8 +/- 2.2 x 10(10), and the mean number of IL-2 doses administered during the last phase was 9.8 +/- 2.5. Nineteen patients completed the IL-2 priming phase and received at least one LAK cell infusion.(ABSTRACT TRUNCATED AT 250 WORDS)
Treatment with interleukin-2 (IL-2) used alone or in combination with lymphokine-activated killer (LAK) cells is known to be an active therapy for patients with advanced renal cell carcinoma and melanoma. To further explore the activity of IL-2/LAK cell therapy in patients with advanced cancer of various primary sites, the Extramural IL-2/LAK Working Group (ILWG) initiated two phase II trials of high-dose IL-2/LAK therapy: one in patients with advanced breast carcinoma, and one in patients with advanced cancer arising in other sites. Patients with advanced renal cell carcinoma, melanoma, colorectal carcinoma, and lymphoma (Hodgkin's and B-cell non-Hodgkin's) were not eligible for the latter trial, but were treated on other ILWG trials that have been reported previously. Sixty-nine patients received high-dose IL-2 (600,000 IU/kg administered by a 15-min intravenous infusion every 8 h) on days 1-5 and days 11-15. Leukapheresis was performed for collection and ex vivo expansion of LAK cells on days 7-10, and the LAK cells were reinfused on days 11, 12, and 14. The studies were designed to determine whether treatment with IL-2/LAK resulted in at least a 40% response rate, a level of activity that was believed to be sufficient to justify the toxicity and cost of IL-2/LAK therapy. An adequate number of patients with carcinoma of the breast (N = 12), pancreas (N = 8), ovary (N = 7), and lung (non-small cell; N = 6) were accrued to assess response; most of these patients had prior chemotherapy that had failed.(ABSTRACT TRUNCATED AT 250 WORDS)
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PURPOSE: To provide an investigational drug, paclitaxel, now commercially available, to women with refractory ovarian cancer and to evaluate response and toxicity in these patients. PATIENTS AND METHODS: Patients with platinum-refractory ovarian cancer, Eastern Cooperative Oncology Group (ECOG) performance status 0 to 3, at least three prior chemotherapy regimens, adequate hepatic and renal function, and no significant cardiac history were eligible. Patients were treated with paclitaxel 135 mg/m2 administered by 24-hour continuous intravenous infusion every 3 weeks. RESULTS: Leukopenia was the most frequent toxicity, with 78% of patients experiencing grade 3 or 4 toxicity. Other grade 3 and 4 toxicities were less common: fever (33%), infection (12%), thrombocytopenia (8%), vomiting (7%), cardiac (2%), neurologic (2%), and mucositis (1%). Fifteen treatment-related deaths (1.5%) were reported. The objective response rate was 22% (4% complete response [CR], 18% partial response; 95% confidence interval [CI] for overall response, 19% to 25%). The median time to progression from treatment initiation was 7.1 months in responding patients and 4.5 months for all patients. The median survival duration was 8.8 months. CONCLUSION: Paclitaxel has shown activity in women with platinum-refractory ovarian cancer, and it can be administered with an acceptable safety profile. Further research is needed to determine the optimal role of paclitaxel in the primary and salvage treatment of ovarian cancer.
Based on the above considerations, there are a number of implications for the clinical development of rIL-2 that depend on the putative effector cell. If the effector cell responsible for rIL-2-mediated antitumor effects is the LAK cell, effective treatment regimens will likely continue to require extremely high doses of rIL-2. Based on preclinical models, one would also predict that LAK cell-mediated tumor killing against nonimmunogenic tumors would be most effective in low tumor burden states and could only be demonstrated clinically in large-scale, randomized, adjuvant trials. On the other hand, some weakly immunogenic tumors might be susceptible to CTL-mediated killing even when disease was further advanced. The antitumor activity of rIL-2 in patients with large tumors suggests that this might be the case for some patients with RCC. Treatment approaches that result in the generation of relevant effector cell populations would be expected to markedly enhance CTL-dependent rIL-2 antitumor activity. However, unless antigenic heterogeneity was minimal, multiple tumor antigen-specific T-cell populations would have to be generated for responses to be complete and durable.
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BACKGROUND: Interferon alfa has been found to be effective as an antitumor agent (with a response rate of 30 percent) in patients with low-grade non-Hodgkin's lymphoma, but its effectiveness in those with intermediate-grade non-Hodgkin's lymphoma has been less adequately tested. In a prospective randomized study we evaluated the effectiveness of adding interferon alfa to cytotoxic chemotherapy in patients with clinically aggressive, low-grade non-Hodgkin's lymphoma and certain histologic variants of intermediate-grade non-Hodgkin's lymphoma, not including diffuse histiocytic lymphoma. METHODS: The patients were randomly assigned to a regimen of cyclophosphamide, vincristine, prednisone, and doxorubicin or to this regimen combined with recombinant interferon alfa. Treatment was administered every four weeks, for 8 to 10 cycles. RESULTS: The two regimens produced comparable objective responses, but the regimen including interferon had a greater effect in prolonging the time to treatment failure (P < 0.001) and the duration of complete response (P = 0.03). Interferon alfa also had a greater effect on overall survival (P = 0.014) when the results were adjusted for important covariates. CONCLUSIONS: Interferon alfa, when added to a four-drug doxorubicin-based chemotherapy regimen, is an effective antitumor agent in patients with clinically aggressive low-grade or intermediate-grade non-Hodgkin's lymphoma.
University students (n = 234) enrolled in sections of a required undergraduate course were administered the Center for Epidemiologic Studies Depression (CES-D) Scale and the Maladaptive Eating Behavior (MEB) Scale to determine if selected maladaptive eating practices correlated with depressive symptoms. Stepwise multiple regression on data from female subjects (n = 138) revealed that four eating practices related to depression, and produced a multiple R = .68, accounting for 46.2% of the variance. Maladaptive eating practices were not predictive of depression among males (n = 96) with "feeling uncomfortable eating in the presence of others" the only significantly correlated variable. This study confirms previous research that has found an association between maladaptive eating practices and depressed mood in nonclinical samples of university students.
This study examined the correlations of 21 variables categorized into sociodemographic, subjective quality of life, stress, problem behavior, and health behavior predictors of at-risk and low-risk depressive symptomatology for a sample of 1056 adolescents attending public school. Discriminant function analysis showed lower life satisfaction, higher stress, and perceived unattractiveness as major discriminating variables for at-risk (CES-Depression score greater than 23) versus low-risk depressed adolescents. Only two problem behaviors were significant, smoking for girls and hard drug use for boys.