Wijnhoven, B P L; Tilanus, M G J; Morris, A G; Darnton, S J; Tilanus, H W; Dinjens, W N M
doi: 10.1054/bjoc.1999.1170pmid: 10789716
In two recently described human oesophageal adenocarcinoma cell lines JROECL 47 and JROECL 50, derived from one tumour, we detected identical E-cadherin and β-catenin gene mutations as in colon carcinoma cell line HCT 116. We demonstrate by HLA-typing, mutation analysis and microsatellite analysis that cell lines JROECL 47 and JROECL 50 are admixtures of the human colon adenocarcinoma cell line HCT 116. © 2000 Cancer Research Campaign
Dellian, M; Yuan, F; Trubetskoy, V S; Torchilin, V P; Jain, R K
doi: 10.1054/bjoc.1999.1171pmid: 10789717
Molecular charge is one of the main determinants of transvascular transport. There are, however, no data available on the effect of molecular charge on microvascular permeability of macromolecules in solid tumours. To this end, we measured tumour microvascular permeability to different proteins having similar size but different charge. Measurements were performed in the human colon adenocarcinoma LS174T transplanted in transparent dorsal skinfold chambers in severe combined immunodeficient (SCID) mice. Bovine serum albumin (BSA) and IgG were fluorescently labelled and were either cationized by conjugation with hexamethylenediamine or anionized by succinylation. The molecules were injected i.v. and the fluorescence in tumour tissue was quantified by intravital fluorescence microscopy. The fluorescence intensity and pharmacokinetic data were used to calculate the microvascular permeability. We found that tumour vascular permeability of cationized BSA (pI-range: 8.6–9.1) and IgG (pI: 8.6–9.3) was more than two-fold higher (4.25 and 4.65 × 10–7cm s–1) than that of the anionized BSA (pI ≈ 2.0) and IgG (pI: 3.0–3.9; 1.11 and 1.93 × 10–7cm s–1, respectively). Our results indicate that positively charged molecules extravasate faster in solid tumours compared to the similar-sized compounds with neutral or negative charges. However, the plasma clearance of cationic molecules was ~2 × faster than that of anionic ones, indicating that the modification of proteins enhances drug delivery to normal organs as well. Therefore, caution should be exercised when such a strategy is used to improve drug and gene delivery to solid tumours. © 2000 Cancer Research Campaign
Hughes, A N; Griffin, M J; Newell, D R; Calvert, A H; Johnston, A; Kerr, B; Lee, C; Liang, B; Boddy, A V
doi: 10.1054/bjoc.2000.1172pmid: 10789718
A clinical study of nolatrexed dihydrochloride (AG337, Thymitaq™) in combination with paclitaxel was performed. The aims were to optimize the schedule of administration and determine any pharmacokinetic (PK) interactions between the two drugs. In vitro combination studies were performed to assist with schedule optimization. Three patients were entered on each of three different schedules of administration of the two drugs: (1) paclitaxel 0–3 h, nolatrexed 24–144 h; (2) nolatrexed 0–120 h, paclitaxel 48–51 h; (3) nolatrexed 0–120 h, paclitaxel 126–129 h. Paclitaxel was administered at a dose of 80 mg m–2over 3 h and nolatrexed at a dose of 500 mg m–2day–1as a 120-h continuous intravenous infusion. Plasma concentrations of both drugs were determined by high performance liquid chromatography. In vitro growth inhibition studies using corresponding schedules were performed using two head and neck cancer cell lines. In both HNX14C and HNX22B cell lines, synergistic growth inhibition was observed on schedule 2, whereas schedules 1 and 3 demonstrated antagonistic effects. In the clinical study, there was no effect of schedule on the pharmacokinetics of nolatrexed. However, patients on schedules 1 and 3 had a higher clearance of paclitaxel (322–520 ml min–1m–2) than those on schedule 2 (165–238 ml min–1m–2). Peak plasma concentrations (1.66–1.93 vs 0.86–1.32 μM) and areas under the curve (392–565 vs 180–291 μM min–1) of paclitaxel were correspondingly higher on schedule 2. The pharmacokinetic interaction was confirmed by studies with human liver microsomes, nolatrexed being an inhibitor of the major routes of metabolism of paclitaxel. Toxicity was not schedule-dependent. Nolatrexed and paclitaxel may be safely given together when administered sequentially at the doses used in this study. Studies in vitro suggest some synergy, however, due to a pharmacokinetic interaction, paclitaxel doses should be reduced when administered during nolatrexed infusion. © 2000 Cancer Research Campaign
doi: 10.1054/bjoc.2000.1173pmid: 10789719
Angiogenesis of tumours might develop as a result of environmental conditions, such as hypoxia, and/or as a result of genetic alterations specific for tumour cells. The relative contributions of these mechanisms were investigated by comparing the in vivo expression of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) to the hypoxic fraction, the angiogenic potential and the vascular density of four human melanoma lines (A-07, D-12, R-18, U-25) grown intradermally in Balb/c nu/nu mice. VEGF expression, bFGF expression and expression of pimonidazole, a marker of hypoxic cells, were investigated by immunohistochemistry. An association between high VEGF and bFGF expression and high angiogenic potential was detected, suggesting an important role for VEGF/bFGF in the angiogenesis of melanomas. High VEGF/bFGF expression was also related to low hypoxic fraction and high vascular density. Thus, the constitutive, genetically determined level of VEGF was probably more important than hypoxia-induced upregulation in the angiogenesis of the melanoma xenografts. © 2000 Cancer Research Campaign
doi: 10.1054/bjoc.2000.1174pmid: 10789720
Currently the only tumour marker to have a well-defined and validated role in the management of ovarian cancer is CA125. Changes in the level of CA125 can be used as a reliable indication of response or progression according to various criteria, but it does not yet have a clear place in diagnosis or prognosis. Its value as part of a screening tool and during routine follow-up remain the subject of ongoing trials. Other markers remain experimental and do not have a well-defined contribution to make at present. © 2000 Cancer Research Campaign
Vahrmeijer, A L; van Dierendonck, J H; Keizer, H J; Beijnen, J H; Tollenaar, R A E M; Pijl, M E J; Marinelli, A; Kuppen, P J K; van Bockel, J H; Mulder, G J; Velde, C J H van de
doi: 10.1054/bjoc.2000.1175pmid: 10789721
A phase I dose-escalation study was performed to determine whether isolated hepatic perfusion (IHP) with melphalan (L-PAM) allows exposure of the liver to much higher drug concentrations than clinically achievable after systemic administration and leads to higher tumour concentrations of L-PAM. Twenty-four patients with colorectal cancer confined to the liver were treated with L-PAM dosages escalating from 0.5 to 4.0 mg kg–1. During all IHP procedures, leakage of perfusate was monitored. Duration of IHP was aimed at 60 min, but was shortened in eight cases as a result of leakage from the isolated circuit. From these, three patients developed WHO grade 3–4 leukopenia and two patients died due to sepsis. A reversible elevation of liver enzymes and bilirubin was seen in the majority of patients. Only one patient was treated with 4.0 mg kg–1L-PAM, who died 8 days after IHP as a result of multiple-organ failure. A statistically significant correlation was found between the dose of L-PAM, peak L-PAM concentrations in perfusate (R = 0.86, P≤ 0.001), perfusate area under the concentration-time curve (AUC; R = 0.82, P< 0.001), tumour tissue concentrations of L-PAM (R = 0.83, P = 0.011) and patient survival (R = 0.52, P = 0.02). The peak L-PAM concentration and AUC of L-PAM in perfusate at dose level 3.0 mg kg–1(n = 5) were respectively 35- and 13-fold higher than in the systemic circulation, and respectively 30- and 5-fold higher than reported for high dose oral L-PAM (80–157 mg m–2) and autologous bone marrow transplantation. Median survival after IHP (n = 21) was 19 months and the overall response rate was 29% (17 assessable patients; one complete and four partial remissions). Thus, the maximally tolerated dose of L-PAM delivered via IHP is approximately 3.0 mg kg–1, leading to high L-PAM concentrations at the target side. Because of the complexity of this treatment modality, IHP has at present no place in routine clinical practice. © 2000 Cancer Research Campaign
Dobson, L S; Lorigan, P C; Coleman, R E; Hancock, B W
doi: 10.1054/bjoc.2000.1176pmid: 10789722
Persistent gestational trophoblastic disease is potentially fatal, but the majority of patients are cured with chemotherapy. Any developments in treatment are therefore being directed towards maintaining efficacy and reducing toxicity. We evaluated efficacy and toxicity of methotrexate, etoposide and dactinomycin (MEA) as first-line therapy for high risk disease and etoposide and dactinomycin (EA) as second-line therapy for methotrexate-refractory low risk disease in a retrospective analysis of 73 patients (38 MEA, 35 EA) treated since 1986 at a supra-regional centre. The median follow-up period was 5.5 years and the median number of cycles received was 7. The overall complete response rate was 85% (97% for EA, 75% for MEA). Of eight patients who failed to respond, four have since died and four were cured with platinum-based chemotherapy. Alopecia was universal. Grade II or worse nausea, emesis, or stomatitis was observed in 29%, 30% and 37% respectively. Fifty-one per cent experienced grade II/III anaemia, 8% grade II or higher thrombocytopenia and 64% grade III or IV neutropenia; in six cases this was complicated by sepsis. Fifty-four per cent of patients went on to have a normal pregnancy. No patient has developed a second malignancy. In conclusion, the MEA and EA chemotherapy regimens for persistent trophoblastic disease are very well tolerated, do not appear to affect future fertility and are associated with excellent, sustained complete response rates. © 2000 Cancer Research Campaign
Butler, S A; Ikram, M S; Mathieu, S; Iles, R K
doi: 10.1054/bjoc.2000.1177pmid: 10789723
Ectopic production of free beta human chorionic gonadotrophin (hCGβ) by bladder carcinoma is well described and occurs in approximately 35% of cases. hCGβ secreting tumours are more aggressive, radioresistant and have a greater propensity to metastasize. We proposed that the ectopic production of hCGβ was contributing in an autocrine fashion to the radioresistance and metastatic potential of such secreting tumours. Though we demonstrated that the addition of hCGβ to the culture media of bladder, cervical and endometrial carcinoma cell lines brought about an increase in cell populations this was not accompanied by a significant increase in the rate of replication. Since a cell population size is a balance of mitosis and mortality, we proposed that hCGβ was inhibiting apoptosis. Here we have demonstrated that following incubation with recombinant hCGβ, bladder carcinoma cells refrain from undergoing apoptosis. Quantitation of apoptotic bodies was carried out by immunoassay and corrected to cell number as determined by MTT assay. In each cell line, addition of hCGβ reduced the number of apoptotic bodies dose-dependently, indicating a diminished apoptotic rate. Furthermore, TGFβ1-induced apoptosis could be dose-dependently inhibited by co-incubation with hCGβ. We propose, therefore, that such a decline in apoptosis may account for the cell population increase previously reported. It may also explain the radioresistance and aggressive nature of hCGβ-secreting tumours and the poor prognosis associated therein. © 2000 Cancer Research Campaign
Tanaka, Shinji; Mori, Masaki; Mafune, Ken-ichi; Ohno, Shinji; Sugimachi, Keizo
doi: 10.1054/bjoc.1999.1178pmid: 10789724
Recent investigations revealed microsatellite instability in colon cancers are associated with mutations of the transforming growth factor-β receptor type II gene (TGF-β RII) that encodes a transmembrane protein containing an intracellular serine/threonine kinase domain. Activation of TGF-β receptor type I (RI) and RII by TGF-β induces nuclear translocation of Smad proteins including Smad2 and Smad4 that have been originally identified as tumour suppressor genes. We have previously reported six cases with microsatellite instability in 32 oesophageal carcinomas. In this study, we analysed genetic mutations of TGF-β RII, Smad2 and Smad4 in these oesophageal carcinoma tissues and established 16 cell lines. No genetic mutation was detected in any tissues or cell lines except one tissue sample of microsatellite stable oesophageal carcinoma, that is, a mis-sense mutation of glutamic acid to glutamine at codon 526 (E526Q) in the TGF-β RII serine/threonine kinase domain. Interestingly, the mutant TGF-β RII E526Q can completely inhibit TGF-β-induction of nuclear translocation of Smad4 protein in oesophageal carcinoma cells. This mutation of TGF-β RII that is not associated with microsatellite instability might make a dominant negative effect on TGF-β signal transduction in oesophageal carcinoma. © 2000 Cancer Research Campaign
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