Biomedical subjects

John J Kavanagh

Publications and source records attributed to John J Kavanagh.

26 records · Page 2Linked to original sources

PubMed2003

Anticancer therapy targeting the apoptotic pathway.

Apoptosis, or programmed cell death, has an essential role in controlling cell number in many developmental and physiological settings and in chemotherapy-induced tumour-cell killing. It is a genetically regulated biological process, guided by the ratio of proapoptotic and antiapoptotic proteins. Recently, inducers of apoptosis have been used in cancer therapy. Several studies have attempted to induce apoptosis by triggering the tumour-necrosis-factor-related apoptosis-inducing ligand receptor and the BCL2 family of proteins, and others have targeted the caspases, and proteins that inhibit apoptosis. Most of these therapies are still in preclinical development because of their low efficacy and susceptibility to drug resistance, but some of them have shown promising results. In this article, we review the development and clinical efficacy of proapoptotic drugs that have shown promise.

Antineoplastic Agents↗

PubMed2003

Establishment and characterization of cancer cell cultures and xenografts derived from primary or metastatic Mullerian cancers.

PURPOSE: The purpose of this study was to characterize cell cultures and xenografts derived from patients with ovarian cancer. EXPERIMENTAL DESIGN: Ninety specimens from 67 patients were plated in RPMI 1640 or inoculated in nude mice. Growth characteristics of cell cultures and xenografts were determined. Expression of receptors for estrogen, progesterone, androgen, epithelial growth factor, fibroblast growth factor, HER-2/erbB-2/c-neu proto-oncogene, and the P53 expression were characterized by immunocytochemistry in 28 cell cultures. RESULTS: Forty-nine percent of samples were cultured successfully in vitro. Ascitic and pleural effusion specimens were more likely to produce a cell culture or a xenograft than solid tissue specimens (P < 0.005). All of the cell cultures had an epithelial morphology, and 89% were aneuploid with a mean DNA index of 1.6 (range, 0.9-3.0). Of 54 and 61 specimens inoculated into nude mice i.p. and s.c., 15 (28%) and 18 (30%) produced a xenograft, respectively, with two-thirds of these xenografts being reproducibly tumorigenic. The median time to first passage was 21 weeks for cell cultures and 8-12 weeks for xenografts. Expression of epithelial growth factor receptor, HER-2/erbB-2/c-neu proto-oncogene, fibroblast growth factor receptor, estrogen, progesterone, and androgen was seen in 24, 21, 31, 17, 43, and 18%, respectively. P53 was overexpressed in 62% of cell cultures analyzed. CONCLUSIONS: Ovarian cancer cells collected from effusions are easier to grow in vitro than in vivo. The only characteristic that may be associated with tumorigenicity was abnormal P53 expression. This panel of ovarian cancer materials provides useful models for biological or therapeutical studies.

Animals↗

PubMed2002

Safety and efficacy of transfusions of autologous cryopreserved platelets derived from recombinant human thrombopoietin to support chemotherapy-associated severe thrombocytopenia: a randomised cross-over study.

BACKGROUND: The increasing demand for platelet products, and concern over the transfusion-associated risks of alloimmunisation and infections, have motivated a search for improved methods aimed at keeping exposure to donor antigens to a minimum. Transfusion of thrombopoietin-derived autologous platelets might provide an alternative strategy. We aimed to compare the safety and efficacy of this strategy with that of transfusion with fresh allogeneic platelets in patients with severe chemotherapy-induced thrombocytopenia. METHODS: 20 patients with gynaecological malignancies were treated with two doses of 1.2 microg/kg recombinant human thrombopoietin. From day 12, we aimed to collect 50 units of platelets from these patients by plateletpheresis. Harvested platelets were cryopreserved in ThromboSol and 2% dimethyl sulfoxide (DMSO) for use in subsequent autologous transfusions. Patients then received carboplatin for up to six cycles. Patients were randomly assigned to group A (n=10), which received allogeneic fresh platelets at the first instance of severe thrombocytopenia (platelet count <15,000/microL) and then autologous cryopreserved platelets at the next, or to group B (n=10), which received first autologous and then allogeneic platelets. In subsequent cycles, all patients received autologous platelets while available. The primary endpoint was platelet count increment corrected for the number of platelets transfused and the patients' body-surface area. Analysis was by intention to treat. FINDINGS: Treatment with recombinant human thrombopoietin significantly increased platelet count (median 2.3-fold [range 1.5-3.3], p<0.0001) in all but one patient in group A. The median number of platelets collected per patient was 53 units (14-66) in two collections (one to three). There was no significant difference in the corrected platelet count increments (CCIs) between the 19 paired transfusions of cryopreserved autologous platelets and fresh allogeneic platelets (median 1-h CCI 15.7 vs 19.8, p=0.398; median 24-h CCI 13.0 vs 18.1, p=0.398). 14 of the 19 patients had a good response (1-h CCI >7.5) to their first transfusion of allogeneic platelets. By contrast, all patients had a good response to their first transfusion of autologous platelets (p=0.063). Moreover, no significant decrease in the CCIs (p=0.405) was seen over six cycles after autologous platelet transfusions (n=63). No transfusion reactions or any serious adverse event was recorded during autologous platelet transfusions. INTERPRETATION: Recombinant human thrombopoietin facilitated collection of multiple units of platelets, which could be cryopreserved and reinfused to counteract severe thrombocytopenia during multicycle chemotherapy. Transfusion of autologous cryopreserved platelets derived from recombinant human thrombopoietin can provide a viable strategy to minimise the risks of allogeneic platelet transfusions and provide a long-lasting supply of platelet support.

Adult↗

PubMed2002

Patient preferences regarding side effects of chemotherapy for ovarian cancer: do they change over time?

OBJECTIVE: The goals of this study were to: (1) systematically evaluate patient preferences regarding side effects of high-dose chemotherapy with stem cell support for treatment of advanced ovarian cancer; and (2) assess whether patients' preferences changed over time. METHODS: Forty patients with stage III or IV disease were enrolled in this study. Patients' preferences regarding 12 health states (side effects) were assessed using visual analogue scale (VAS) and time trade-off (TTO) methods during mobilization chemotherapy (T(1)) and 6-7 weeks later after high-dose chemotherapy and stem cell transplant (T(2)). Each assessment involved a 45-min interview conducted at the patient's bedside. RESULTS: The three most preferred health states were no evidence of disease (NED), a chemotherapy with few or no side effects, and alopecia, while the least preferred health states were chemotherapy with multiple severe side effects, hepatotoxicity, and nausea and vomiting. These results were observed at both T(1) and T(2) using both preference assessment methods. Pancytopenia scores significantly increased from T(1) to T(2) using the VAS method (P < 0.05), but decreased using the TTO method. CONCLUSIONS: Chemotherapy-experienced women with ovarian cancer have consistent preferences for the best and worst health states associated with the side effects of chemotherapy. Patients are more averse to nausea and vomiting than many other symptoms. Women's perceptions of pancytopenia may be dependent upon the number of prior cycles of chemotherapy and site of care for anemia, thrombocytopenia, and febrile neutropenia.

Adult↗

PubMed2002

Docetaxel in the treatment of ovarian cancer.

Docetaxel (Taxotere) has extended the armamentarium of agents with significant activity in the treatment of ovarian cancer. As a single agent in advanced ovarian cancer patients previously treated with a platinum agent, docetaxel at 100 mg/m2 every 3 weeks yields a 30% overall response rate and a 6-month duration of response. In vitro data demonstrate a lack of complete cross-resistance between docetaxel and paclitaxel. As a result, antitumor activity has also been demonstrated in patients refractory to a paclitaxel-containing regimen. In both platinum- and paclitaxel-pretreated patients, the highest response rates were obtained in patients with the longest interval of time since receipt of prior chemotherapy. Docetaxel has been successfully combined with the platinum salts for the first-line treatment of ovarian cancer patients. In combination with cisplatin, response rates of 69% were reported. In an effort to minimize hematologic toxicities and asthenia associated with the cisplatin/docetaxel combination, investigators have substituted carboplatin (Paraplatin) for cisplatin. Several phase II studies and the Scottish Randomized Trial in Ovarian Cancer (SCOTROC), a large phase III randomized trial, of the docetaxel/ carboplatin combination have been completed. The most frequent toxicity noted is neutropenia, which is generally of brief duration, predictable, and manageable. The docetaxel/carboplatin combination has a notably low rate of neurotoxicity. Therefore, the SCOTROC comparative trial, demonstrating equivalent overall response rates and progression-free survival rates, suggests that the docetaxel/carboplatin combination may represent a new alternative to paclitaxel/carboplatin as first-line chemotherapy for advanced ovarian cancer.

Antineoplastic Agents, Phytogenic↗

PubMed2002

Phase I study of intraperitoneal recombinant human interleukin 12 in patients with Müllerian carcinoma, gastrointestinal primary malignancies, and mesothelioma.

PURPOSE: The purpose is to determine dose-limiting toxicity, pharmacokinetics,pharmacodynamics, and immunobiology after i.p. injections of recombinant human IL-12 (rhIL-12). EXPERIMENTAL DESIGN: rhIL-12 was administered to 29 previously treated patients with peritoneal carcinomatosis from Müllerian carcinomas, gastrointestinal tract carcinomas and peritoneal mesothelioma in a Phase I trial. rhIL-12 doses were increased from 3 to 600 ng/kg. Three or more patients at each level received weekly i.p. injections of rhIL-12. RESULTS: Dose-limiting toxicity (elevated transaminase) occurred in 2 of 4 patients at the 600 ng/kg dose. More frequent toxicities included fever, fatigue, abdominal pain, nausea, and catheter-related infections. Ten patients received 300 ng/kg with acceptable frequency and severity of side effects. Two patients (one with ovarian cancer and one with mesothelioma) had no remaining disease at laparoscopy. Eight patients had stable disease and 19 progressive disease. At 300 ng/kg i.p., IL-12 was cleared from peritoneal fluid in a biphasic manner with a terminal-phase half-life of 18.7 h; peritoneal fluid levels of IL-12 5 min after i.p. injection were 100-200 pg/ml, and serum levels reached approximately 10 pg/ml between 24 and 36 h. IL-1-alpha, IL-2, IL-10, tumor necrosis factor alpha, and IFN-gamma were determined in serum and peritoneal fluid. IFN-gamma, IL-10, and tumor necrosis factor alpha were detected most frequently. Immunobiological effects included peritoneal tumor cell apoptosis, decreased tumor cell expression of basic fibroblast growth factor and vascular endothelial growth factor, elevated IFN-gamma and IFN-inducible protein 10 transcripts in peritoneal exudate cells, and increased proportions of peritoneal CD3(+) relative to CD14(+) cells. CONCLUSIONS: rhIL-12 at 300 ng/kg by weekly i.p. injection is biologically active and adequately tolerated for Phase II studies.

Adenocarcinoma↗

PubMedDate not supplied

Intraperitoneal fluid neopterin, nitrate, and tryptophan after regional administration of interleukin-12.

Activated monocytes-macrophages may be associated with antitumor activity, and activation of these cells by certain cytokines, primarily interferon gamma (IFN-gamma), can be indicated by alterations in the concentrations of neopterin, nitrate, or tryptophan. Specimens of peritoneal fluid were obtained from patients with intra-abdominal neoplasia who were undergoing treatment in a phase I trial of weekly intraperitoneal recombinant interleukin-12 (rhIL-12), an inducer of IFN-gamma. Concentrations of neopterin, nitrate, tryptophan, IFN-gamma, and tumor necrosis factor alpha (TNF-alpha) were determined at various times during the first 48 hours in 11 patients who received intraperitoneal rhIL-12 in doses ranging from 100 to 1,500 ng/kg. An increase in peritoneal fluid nitrate concentrations was observed in nine of these patients. Increased concentrations of TNF-alpha and IFN-gamma were detected in 3 of 9 and 8 of 11 patients, respectively. Increased peritoneal fluid neopterin concentrations were detected by 24 hours after the injection in all patients studied. A significant increase in the ascitic fluid neopterin level could still be detected after 1 or 2 weeks of treatment (mean +/- standard error, 7.8 +/- 1.5 nM vs. 4.6 +/- 0.3 nM; Wilcoxon test, p = 0.0019), which is consistent with monocyte-macrophage activation. In contrast, the tryptophan concentration was lower (4.7 +/- 1.1 microM vs. 6.1 +/- 1.2 microM; p = 0.0428) after 1 or 2 weeks of treatment. There was a significant correlation between the dose of rhIL-12 and posttreatment neopterin concentrations (r(s) = 0.559, p = 0.0102). The intraperitoneal delivery of rhIL-12 appears to be associated with an immediate, sustained, and dose-dependent increase in peritoneal fluid neopterin, associated in most patients by an increase in IFN-gamma and in certain patients by an increase in nitrate and a decrease in tryptophan concentrations.

Abdominal Neoplasms↗

PubMedDate not supplied

Increased expression of heat shock protein 70 in adherent ovarian cancer and mesothelioma following treatment with manumycin, a farnesyl transferase inhibitor.

Since farnesylation by farnesyltransferase (FTase) is the first obligatory step in the signaling transduction pathway of ras p21, FTase has been the target of new anticancer treatment modalities. Famesyl transferase inhibitors (FTIs), a novel class of antitumor drugs that blocks the oncogenic activity of ras, were first developed as therapy for ras-mutated human tumors. FTIs are also capable of inhibiting tumors without ras mutations, while different mechanisms of cell growth inhibition by FTI have been proposed. In cell culture and in animal models, FTIs have been shown to be potent inhibitors of cancer cell growth. We showed that manumycin, a farnesyl pyrophosphate competitive inhibitor, inhibits ovarian and mesothelioma cancer cell growth. To examine the molecular changes after exposure to manumycin, total proteins from treated and untreated 2774 cell line were extracted and separated by two dimensional gel electrophoresis (2-DE) and detected by colloidal coomassie blue staining. The 2-DE was found reliable for comparison of protein profiles before and after manumycin treatment. Two protein spots (spot 1 and 2) appeared after manumycin treatment. Generated peptide peaks were matched by database query (prowl.rockefeller.edu/cgi-bin/ProFound) to a heat shock protein (HSP) and a modified HSP, both with MW 70 KD. The expression status of HSP 70 was confirmed by Western blot and HSP 70 ELISA using an antibody against HSP 70. The expression of HSP70 increased with the length of exposure to, and the dose of manumycin as demonstrated by ELISA. Increase in HSP70 expression was also observed by Western blot after a 48-hour treatment with manumycin in ovarian cancer cell line OVCAR3 and three other cell cultures derived from samples of patients diagnosed with ovarian cancer and mesothelioma. Our study is the first report demonstrating an up-regulation of HSP 70 in ovarian cancer cell lines and mesothelioma cell cultures after treatment with the FTI, manumycin. This up-regulation of HSP 70 may be a cellular mechanism of cell self-protection against the apoptotic process and cell death, and it may enhance resistance and account for the altered sensitivity of certain cancers to FTIs agents. HSPs may therefore be an important molecular target for drug intervention strategies.

Alkyl and Aryl Transferases↗