Angiogenic oligosaccharides of hyaluronan induce protein tyrosine kinase activity in endothelial cells and activate a cytoplasmic signal transduction pathway resulting in proliferation

We have recently shown that the degradation products of hyaluronan of 3 to 10 disaccharides (o-HA), but not native high molecular weight hyaluronan, can induce angiogenesis in vivo and, as such, o-HA is an important regulator of the neovascularization process. As a continuation of this work, we have studied the cytoplasmic signal transduction pathways responsible for o-HA-activated endothelial cell proliferation. We show that the addition of o-HA (1 microg/ml) to bovine aortic endothelial cells induces tyrosine phosphorylation of multiple proteins within 1 minute and that the activity remains above basal levels for at least 24 hours. Increased phosphorylation of the CD44 receptor was also observed. Pretreatment of cells with an anti-CD44-receptor antibody (5 microg/ml) or the tyrosine kinase inhibitor genistein (10 microM) inhibited both o-HA-induced proliferation (p < 0.05) and protein tyrosine phosphorylation. In comparison, native hyaluronan had little effect on tyrosine phosphorylation across the same time period. Protein kinase C (PKC) activity was increased 2- to 3-fold in the membranes of cells treated with o-HA, and a pretreatment with phorbol 12,13-dibutyrate (PDBu) to down-regulate PKC significantly inhibited o-HA-induced cell proliferation (p < 0.05). Examination by Western blotting showed that only the betaI and epsilon isoforms remained translocated to the membrane for at least 24 hours. These isoforms seem to be involved in modulating the proliferative effects of o-HA, because the transient translocation of PKC isoforms by PDBu was not sufficient to induce mitogenesis. Furthermore, we show that PKC activation of the cytoplasmic kinase cascade (Raf-1 kinase, MAP kinase kinase [MEK-1], and extracellular signal-regulated kinase [ERK-1]) by o-HA culminated in the nuclear translocation of ERK-1. This pathway is essentially linear, as shown by the ability of specific enzyme inhibitors (PDBu and PD98059) to prevent both activation of ERK-1- and o-HA-induced proliferation. We conclude that phosphorylation of the CD44 receptor results in an increase in tyrosine phosphorylation, leading to the activation of a cytoplasmic cascade and cell proliferation; this concurs with previous work, which showed that o-HA-induced proliferation of endothelial cells is CD44-receptor-mediated and accompanied by early response gene activation.

Randomized trial of dose-intensity with single-agent carboplatin in patients with epithelial ovarian cancer. London Gynaecological Oncology Group

PURPOSE

We have examined the role of an increase in cisplatin dose-intensity in patients with advanced epithelial ovarian cancer by means of single-agent carboplatin therapy.

PATIENTS AND METHODS

Two hundred twenty-seven patients were randomized to treatment and eligible for analysis. The dose of carboplatin was calculated according to the Calvert formula. One hundred seventeen patients received carboplatin at an area under the concentration time curve (AUC) of 6 for six courses, administered every 28 days, and 110 patients received carboplatin at an AUC of 12 for four courses, administered every 28 days. Patients were eligible provided they had not received prior chemotherapy or radiotherapy and had International Federation of Gynecology and Obstetrics stages II to IV or relapsed stage I epithelial ovarian cancer.

RESULTS

The planned total-dose increase was 33% for the patients treated with carboplatin AUC 12, but the received percentage total-dose increase was 20%. There were no differences in progression-free or overall survival between the two treatment arms; the overall survival rate at 5 years was 31% and 34% of patients treated at AUCs 6 and 12, respectively. There was significantly more toxicity associated with carboplatin AUC 12, which resulted in more treatment delays and/or dose reductions (52% v 18%; P < .001).

CONCLUSION

We have shown that carboplatin can be delivered at an AUC of 12 for four courses without granulocyte colony-stimulating factor support, although significant hematologic toxicity occurs. Nonhematologic toxicities were not clinically significant. Carboplatin offers an opportunity to intensify cisplatin therapy, but a greater than two-fold increase in dose-intensity probably needs to be achieved before significant effects on survival will be produced and hematologic support will be required.

Effects of haemopoietic growth factors in combination with etoposide on sister chromatid exchange frequencies in peripheral blood mononuclear cells

Prior to work on the influence of dosing and scheduling of the drug etoposide in bone marrow cells, the DNA-damaging effects of three haemopoietic growth factors, either alone or in combination with etoposide, were investigated. Sister chromatid exchange (SCE) frequencies in phytohaemagglutinin-stimulated mononuclear cells of six normal volunteers were used as an indicator of DNA damage. The effects of three growth factors on SCEs were investigated at concentrations ranging between 0 and 100 ng/ml and those of etoposide alone, at concentrations varying between 0 and 2 microM. The effect of combinations of growth factor (GF) and etoposide were assessed at a 40-ng/ml concentration of each cytokine and at 0.4 microM etoposide. Results showed not only a dose-dependent rise in SCE frequency in cells treated with etoposide but also a cytokine effect. Stem-cell factor did not cause a significant change in SCE numbers. However, cytokines with activity at the progenitor cell level induced small but significant increases in SCE numbers at concentrations of 50 and 100 ng/ml (P < 0.001). Results of combination studies indicated a significant 60% increase in SCE numbers in cells treated with GF and etoposide as compared with etoposide alone (P < 0.00001). This finding suggests a sensitivity of peripheral blood mononuclear cells to SCE induction by GFs given either as single agents or in combination with etoposide.

Retinopathy of prematurity screening, stress related responses, the role of nesting

AIMS/BACKGROUND

In a prospective study the degree of distress caused by retinopathy of prematurity (ROP) screening in a cohort of preterm infants was assessed and the modifying effects of nesting in reducing their discomfort was evaluated.

METHODS

38 preterm infants were included in the study. 19 infants were placed in a nest with boundaries (intervention group) and 19 infants were placed on a cot blanket (control group). Observations were made 2 minutes before, throughout, and 2 minutes after ROP examination. The factors observed were crying responses, neurobehavioural activity, and physiological changes (heart rate, oxygen saturation). Recordings were made using a video camera for crying and neurobehavioural activity and an Oxypleth monitor for heart rate and oxygen saturation.

RESULTS

During ROP screening, the total group of 38 infants (nested and non-nested combined) displayed increased neurobehavioural activity (p < 0.01) and crying (p < 0.01). The increased activity and crying coincided with the invasive part of the procedure. The distress caused by ROP screening was significantly less for the nested group compared with the non-nested group for both movement activity (p < 0.01) and crying (p < 0.01). The physiological data, heart rate, and oxygen saturation were not statistically significant.

CONCLUSION

ROP screening is distressing for preterm infants. Nesting can significantly reduce this discomfort. The findings in this study are of value in designing more optimal ROP examination schedules for infants.

A putative role for platelet-derived growth factor in angiogenesis and neuroprotection after ischemic stroke in humans

BACKGROUND AND PURPOSE

Growth factors control two important processes in infarcted tissue, ie, angiogenesis and gliosis. We recently reported that transforming growth factor-beta1 (TGF-beta1) might be involved in angiogenesis after ischemic stroke in humans; here we present data of an extensive study on platelet-derived growth factor (PDGF) and its receptors.

METHODS

We studied brain samples from patients who suffered from ischemic stroke for the expression of mRNA encoding PDGF-A, PDGF-B, and PDGF receptors (PDGF-R). Proteins were examined by Western blotting and immunohistochemistry using the antibodies to PDGF-AB, PDGF-BB, PDGF-R alpha, and PDGF-R beta.

RESULTS

At the mRNA level, PDGF-A and PDGF-B were expressed mainly in neurons in penumbra. PDGF-R mRNA was strongly expressed in some astrocytes but mainly in type III/IV neurons in infarct and penumbra. The least expression was seen in the contralateral hemisphere (P<.001). In contrast, both PDGF-AB and PDGF-BB immunoreactive products were present in most cell types: PDGF-R alpha and PDGF-R beta mainly on neurons, and PDGF-R beta on some endothelial cells, with less staining of all the isoforms in the contralateral hemisphere. On Western blots, PDGF-AB and -BB were expressed more within white matter than gray matter of infarct/penumbra, whereas both isoforms of receptor were expressed mainly in gray matter compared with contralateral hemisphere. There was no or very weak expression of the receptor in white matter.

CONCLUSIONS

PDGF proteins are highly expressed in white matter, suggesting that PDGF may exert its function in white matter participating either in regeneration of damaged axons or in glial scar formation. PDGF-BB and its receptor expressed on microvessel endothelial cells might be involved in angiogenesis after stroke. Thus, PDGF is likely to be angiogenic and neuroprotective in stroke.

Single-agent paclitaxel in patients with previously untreated stage IV epithelial ovarian cancer. London Gynaecological Oncology and North Thames Gynaecological Oncology Groups

The aim of this study was to evaluate the efficacy of high-dose paclitaxel in patients with previously untreated stage IV epithelial ovarian cancer. Paclitaxel was administered intravenously over 3 h at a dose of 225 mg m(-2) on a 21-day cycle for six courses. Thirty-six patients were entered into this study; all 36 were assessed for toxicity and 33 patients were evaluable for response. One patient had a complete response and 12 patients had partial responses (overall response rate 39.4%, 95% CI 23-58%). The overall median duration of response was 9 months (range 3.5-23+ months). The response rate to carboplatin following failure of paclitaxel within 1 year of stopping therapy was 57% (four out of seven patients). The median survival of patients was 17.2 months. The main toxicity encountered was neutropenia which was WHO grade 3 in 11 patients (31%) and WHO grade 4 in seven patients (19%). Granulocyte colony-stimulating factor (GCSF) was not given to any patient during the study. Other toxicities were: grade 3/4 infection (11%) and nausea and vomiting (11%); grade 3 bone pain (22%), fatigue (14%), diarrhoea (3%), myalgia/arthralgia (3%) and dry eyes (3%). Transient peripheral neuropathy occurred in 16 patients (44%), and alopecia was encountered in most patients (grade 2/3, 78%). Paclitaxel given at 225 mg m(-2) to patients with stage IV epithelial ovarian cancer is active, well tolerated and does not require GCSF support.

Continuous infusional topotecan in advanced breast and non-small-cell lung cancer: no evidence of increased efficacy

Two open, phase II studies were performed to evaluate the activity and toxicity of infusional topotecan in patients with advanced non-small-cell lung carcinoma (NSCLC) and advanced breast cancer who had not received previous chemotherapy for metastatic disease. Twenty-five patients with an ECOG performance score < 2 were treated with infusional topotecan administered as a daily, continuous intravenous infusion starting at 0.6 mg m(-2) day(-1) (NSCLC) and 0.5 mg m(-2) day(-1) (breast cancer) for 21 days every 4 weeks. Three patients achieved a partial response as defined by WHO criteria: one with NSCLC (8%; 95% CI 0-39%) and two with advanced breast cancer (15%; 95% CI 2-45%). The major toxicities were neutropenia and thrombocytopenia, with one episode of neutropenic sepsis. These data suggest that topotecan delivered as a continuous intravenous infusion over 21 days as single-agent therapy does not appear to offer a clinical advantage over conventional 5-day schedules against advanced NSCLC and advanced breast cancer.

Therapeutic monitoring of continuous infusion etoposide in small-cell lung cancer

PURPOSE

To investigate the feasibility of therapeutic monitoring of etoposide at different plasma concentrations of the drug, and the resulting pharmacodynamic effects of such an approach.

PATIENTS AND METHODS

Forty-nine previously untreated small-cell lung cancer (SCLC) patients received single-agent etoposide every 3 weeks by continuous infusion over 5 days. Plasma etoposide concentrations were monitored 18 and 66 hours into the infusion to permit dose modification. The first cohort of 15 patients began treatment with etoposide 2 micrograms/mL, with dose escalation to 3 micrograms/mL for cycles 3 and 4 and 4 micrograms/mL for cycles 5 and 6, toxicity permitting. The second cohort of 34 patients commenced at 3 micrograms/mL, with dose escalation to 4 and 5 micrograms/mL on cycles 3 and 5, respectively.

RESULTS

Mean plasma etoposide concentration during the first treatment cycle was 93.4% +/- 26.6% of the target level at 18 hours (57% of patients within +/- 20% of the target) and 98.9% +/- 14.5% of the target level at 66 hours (82% of patients within +/- 20%). Hematologic toxicity was more pronounced in those treated with 3 micrograms/mL versus 2 micrograms/mL (median nadir neutrophil count, 1.3 v 2.6 x 10(9)/L, P = .032). Tumor responses, typically documented by the third cycle, were similar in each cohort (71% in patients commenced at 2 micrograms/mL and 70% at 3 micrograms/mL). Treatment cohort was not independently predictive of survival.

CONCLUSION

Therapeutic monitoring of infusional etoposide is feasible and dramatically reduces interpatient pharmacokinetic variability. Although this was a small nonrandomized trial, the observation of different hematologic toxicity at the two starting concentrations but similar antitumor activity further suggests that these effects may be associated with different plasma etoposide concentrations.

The ganglioside profile of human bladder cell lines and the effect of exogenous gangliosides on their growth

The ganglioside composition of three human bladder cell lines, two tumourigenic (RT112 and EJ138) and one non-tumourigenic (Hu609) were analysed by thin-layer chromatography and mass spectroscopy. Sub-confluent cultures of the three cell lines expressed mainly monosialogangliosides. Xenografts of EJ138 cells expressed nearly twice as much GM(3) as tissue cultured cells. Proliferation of Hu609 and EJ138 cells measured by H-3-thymidine incorporation was increased by GM(3) and further enhanced by addition of EGF. Paradoxically the migration of all three cell lines was inhibited by a mixture of monosialogangliosides and the inhibition was abolished by EGF.

Volunteers or victims: patients' views of randomised cancer clinical trials

Randomised clinical trials are essential for the objective evaluation of different treatment strategies in cancer. However, in the field of oncology, very few of the eligible patients are entered into trials, and most treatments have only been tested on a small percentage of patients. For doctors, a major deterrent to participating in trials is the lack of resources--particularly time, but often also the local facilities. This report suggests that patients themselves are willing to take part in clinical research, and are attracted by being treated by a doctor with a specialist interest in the disease and encouraged by the possibility that their progress will be monitored closely. With the recent NHS changes, it is timely for the Department of Health and other national health departments to consider carefully what can be done to ensure that no new treatments are adopted without effective evaluation. This will require departments of health to identify and implement ways to facilitate accrual of appropriate numbers of patients onto research protocols (whether non-randomised phase I or phase II studies or large, multicentre phase III trials) over short time periods.

A randomised study of carboplatin vs sequential ifosfamide/carboplatin for patients with FIGO stage III epithelial ovarian carcinoma. The London Gynaecologic Oncology Group

In a study designed to compare response rates of patients with stage III epithelial ovarian carcinoma to ifosfamide and carboplatin, 152 patients were randomised to receive either sequential therapy with three cycles of ifosfamide followed by three cycles of carboplatin, or to six cycles of single agent carboplatin. Ifosfamide was given every 3 weeks in a dose of 5 gm m-2 as a 24 h infusion with mesna, 1 gm m-2 by i.v. bolus prior to ifosfamide, 3 gm m-2 with ifosfamide, and 1 gm m-2 as an 8 h infusion after ifosfamide. Carboplatin was given in a dose of 400 mg m-2 by short i.v. infusion every 4 weeks. Sixty-eight evaluable patients were randomised to sequential ifosfamide/carboplatin, and 67 to single agent carboplatin. Median follow-up is 36 months (range 5.5-82.3). After three cycles of treatment two patients in the ifosfamide/carboplatin arm achieved complete remission (CR), and 12 partial remission (PR) for an overall response rate of 29%, whereas in the carboplatin arm ten patients achieved CR, and 23 PR, for an overall response rate of 63% (P = 0.0008). Seven of 15 patients with progressive disease, and nine of 20 patients with stable disease at the initial response evaluation, following three cycles of ifosfamide, subsequently responded to carboplatin therapy so that the final response rate to the complete regimen was 65% for the ifosfamide/carboplatin arm, compared to 71% for the carboplatin arm (NS). For the ifosfamide/carboplatin arm, median recurrence free survival and overall survival were 14.1 months and 18.7 months. Corresponding figures for the carboplatin arm were 14.5 months and 21.5 months (NS). Both treatments were generally well tolerated. However 47% of patients in the ifosfamide/carboplatin arm developed alopecia sufficient to require a wig, compared to only 2% in the carboplatin arm. Ifosfamide is clearly less effective, and more toxic than carboplatin. Ifosfamide failures can however be effectively salvaged by subsequent carboplatin treatment. Ifosfamide cannot be recommended for single agent therapy in ovarian carcinoma, however the combination of carboplatin plus ifosfamide might be a suitable treatment to be tested in a future randomised study against carboplatin alone.

The pharmacokinetics of morphine and morphine glucuronides in kidney failure

The pharmacokinetics of morphine and its glucuronide metabolites were investigated in three groups of patients with kidney failure (nondialyzed, receiving dialysis, and transplantation) and compared with a group of normal healthy volunteers. Patients in all three renal groups were undergoing surgical procedures (nondialyzed group undergoing arteriovenous fistula formation, dialysis group undergoing placement of a peritoneal dialysis catheter, and the transplant group undergoing live donor kidney transplant). A sensitive, specific high-performance liquid chromatographic assay was used to quantitate morphine, morphine-3-glucuronide, and morphine-6-glucuronide. Patients with kidney failure had a significantly increased morphine area under the curve (AUC) compared with control subjects. There was also an increase in the metabolites morphine-3-glucuronide and morphine-6-glucuronide that was severalfold greater than the increase in morphine AUC. This metabolite accumulation was reversed by kidney transplantation, providing an elegant confirmation on the role of the kidney in morphine pharmacology.

Pharmacokinetics of 5-fluorouracil in colorectal cancer patients receiving interferon

BACKGROUND

The outlook for patients with advanced colorectal cancer remains poor. Recent reports of the combination of 5-fluorouracil (5-FU) and alpha-interferon in colorectal cancer have suggested better response rates. One possible explanation for interaction between 5-FU and interferon is that interferon alters the pharmacokinetics of 5-FU, increasing plasma 5-FU levels.

PATIENTS AND METHODS

To investigate the possibility of interaction between the two agents, steady state 5-FU pharmacokinetics was evaluated in patients with colorectal cancer who received 5-FU by continuous i.v. infusion with and without concurrent administration of subcutaneous alpha-interferon. 5-FU levels were measured by reverse-phase high-performance liquid chromatography.

RESULTS

Twenty-six patients were evaluated. There were 4 partial responses (15%). There was no significant difference in steady state 5-FU levels whether or not alpha-interferon was administered concurrently.

CONCLUSION

Any synergistic activity that may exist between this combination of 5-FU and alpha-interferon is not simply due to altered 5-FU pharmacokinetics.

A double blind placebo controlled trial of medroxyprogesterone acetate (MPA) in cancer cachexia

Patients with breast cancer treated with MPA often report an improvement in appetite. Similar appetite stimulation is seen in patients treated with some corticosteroids, but MPA has a potential advantage over these drugs in that it does not exert a catabolic effect. MPA (100 mg tds orally) has therefore been compared with placebo in 60 patients with advanced malignant disease. Twenty-one patients in the MPA group and 20 in the placebo group were receiving chemotherapy. Patients were treated for 6 weeks and were assessed at weeks 0, 3 and 6 for appetite, energy, mood and pain using visual analogue scales. Nutritional status was assessed by the measurement of serum proteins and anthropometrics. Karnofsky score was recorded as a measure of performance status. There was a significant improvement in appetite in the MPA group between weeks 0 (pre-study) and 3 (P = 0.0002) and 0 and 6 (P = 0.015). There was no significant improvement in appetite in the placebo group. Supporting this finding was the significant increase in serum thyroid binding pre-albumin and retinol binding protein in the MPA group between weeks 0 and 3 and 0 and 6 (P = 0.023 and P = 0.039 respectively). These two parameters showed no significant change in the placebo group. There was no change in anthropometric measurements, weight, performance status, energy, mood or pain in either group. These data indicate that there was a significant increase in appetite in anorexic patients with advanced cancer treated with MPA which was reflected in increases in rapid turnover proteins reported to reflect nutritional status. However, this apparent increase in appetite did not result in improved weight, performance status, energy levels, mood or relief of pain. Further studies to investigate the effect of higher doses of MPA are indicated.

The analgesic activity of morphine-6-glucuronide

1. The pharmacokinetics, cardio-respiratory effects and analgesic effects of intravenous morphine-6-glucuronide were studied in 20 cancer patients with pain. Four different dose levels (0.5, 1, 2, and 4 mg 70 kg-1) were studied. Plasma concentrations of morphine-6-glucuronide were measured for 12 h after dosing. Pulse rate, respiratory rate and blood pressure were monitored, and pain relief was measured using two rating scales and a visual analogue scale. 2. The mean elimination half-life (+/- s.d.) of morphine-6-glucuronide was 3.2 +/- 1.6 h. The mean AUC standardised to a dose of 1 mg 70 kg-1 was 390 +/- 263 nmol l-1 h. Mean morphine-6-glucuronide clearance was 96 +/- 38 ml min-1. There was a direct relationship between morphine-6-glucuronide plasma clearance and calculated creatinine clearance (r = 0.81, P less than 0.001). 38 +/- 22% of the dose of morphine-6-glucuronide was recovered unchanged in the urine in 24 h. No morphine or morphine-3-glucuronide was detected in the plasma or urine of any patient after morphine-6-glucuronide treatment. 3. Morphine-6-glucuronide exerted a useful analgesic effect in 17/19 assessable patients for periods ranging between 2 and 24 h. No correlation was observed between dose or plasma morphine-6-glucuronide concentrations, and duration or degree of analgesia. No clinically significant changes in cardio-respiratory parameters were observed. No patients reported sedation or euphoria. Nausea and vomiting were notably absent in all cases. 4. Morphine-6-glucuronide is an effective and well-tolerated analgesic. It is likely that the majority of the therapeutic benefit of morphine is mediated by morphine-6-glucuronide.(ABSTRACT TRUNCATED AT 250 WORDS)

A multicenter phase II study of carboplatin in advanced ovarian carcinoma: final report

A phase II trial of single-agent carboplatin in advanced ovarian cancer was performed by 19 institutions from 10 European countries. A total of 260 patients were treated, with a median age of 55 (range: 20-79) years. Karnofsky performance status was 80-100 in about two-thirds of the patients. Prior therapy consisted of surgery only in 31 patients, irradiation in 9, chemotherapy without cisplatin in 45, and with cisplatin in 175. Carboplatin was administered as second-line therapy in about one-half and as third-line or more in one additional third of the study population. Initial dose was 400 mg/m2 in 90, 360 mg/m2 in 152, and 320 mg/m2 or less in 18 patients. A total of 971 courses (mean 3.7, median 2, range: 1-13) of therapy were administered. A total of 16 complete and 46 partial responses were observed in 226 evaluable patients, for an objective response rate of 27%. Efficacy was greater in chemotherapy-untreated patients (51% vs. 23%, p = 0.002). In cisplatin-pretreated patients activity was significantly higher in non-refractory patients (26% vs. 4%, p = 0.015). Myelosuppression was the most significant side effect. However, low hematologic counts seldom translated into clinically significant complications. Patients with impaired baseline creatinine clearance and poor performance status were at higher risk of developing severe myelosuppression during the initial course of treatment. Non hematologic side effects were rare and mild, except for emesis. Carboplatin has a definite role in the treatment of ovarian cancer, but almost complete cross-resistance with the parent compound was observed clinically.

Peritoneal mesothelioma: the role of computed tomography in diagnosis and follow up

Computed tomography (CT) was performed on 15 patients with proven peritoneal mesothelioma. Eight of these patients underwent follow-up CT. It was found that a discrete and measurable mass is unusual in comparison with the common occurrence of ascites and that therefore CT has little role in quantifying the disease. Ascites is usually a prominent feature. Other features (e.g. omental infiltration) were evaluated and these could be used to assess disease progression.