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1.  Global acetylation and methylation changes predict papillary urothelial neoplasia of low malignant potential recurrence 
Papillary urothelial neoplasia of low malignant potential (PUNLMP) recurs in approximately 35% of patients. Conventional histopathological assessment does not distinguish non-recurrent from recurrent PUNLMP. The aim of the study was to explore the differences in global histone acetylation and global DNA methylation between non-recurrent and recurrent PUNLMP. Acetylated histone H3 lysine 9 (AcH3K9) and 5-methylcytosine (5MeC) were investigated by immunohistochemistry (IHC) in 20 PUNLMP cases (10 non-recurrent and 10 recurrent), in 5 cases of normal urothelium (NU) and in 5 cases of muscle invasive pT2 urothelial carcinoma (UC). The total optical density of the nuclear staining was measured photometrically in at least 40 nuclei separately for the basal, intermediate and luminal positions in each case. Concerning the total optical density values for both acetylation and methylation, a decrease in staining is observed from non-recurrent PUNLMP to recurrent PUNLMP, at all nuclear locations. For acetylation the mean value in non-recurrent. PUNLMP, intermediate between NU and UC, is closer to the former than to latter. The mean value in recurrent PUNLMP is closer to UC than to NU. In NU, non-recurrent and recurrent PUNLMP the acetylation to methylation ratio decreased from the nuclei in basal position to those in the surface, the average for the above groups being 1.491, 1.611 and 1.746, respectively. Setting the observed values for NU at each sampling location to unity, acetylation shows a steady decrease, the percentages of changes in this nuclear location compared to NU being − 5% in non-recurrent PUNLMP, − 15% in recurrent PUNLMP and − 24% in UC. Concerning methylation, there is slight increase in non-recurrent PUNLMP (+ 5%), a decrease in recurrent PUNLMP (− 19%) followed by a sharp rise for the UC (+ 61%). In conclusion there are differences in global histone acetylation and DNA methylation patterns between non-recurrent and recurrent PUNLMP. Further studies are needed to elucidate the complex interplay between chromatin structure, its modifications and recurrence of PUNLMP.
PMCID: PMC4048711  PMID: 21658323
Urothelium; papillary urothelial neoplasm of low malignant potential; recurrence; global histone acetylation; global DNA methylation
2.  Limits of detection of chemopreventive efficacy 
This study was designed to establish estimates of the smallest effects due to chemopreventive intervention detectable by karyometry in skin biopsies.
Estimates of the smallest change of statistical significance and of the power of the test were derived for a number of key features descriptive of the distribution of nuclear chromatin. Results from triplicate biopsies from the same case were used to provide estimates of the within-case, biopsy-to-biopsy variance.
Generally, a change in feature value due to chemopreventive intervention can be statistically secured when it amounts to 5 to 10%. In clinical trials where matched baseline and end of study biopsies from the same cases are available, paired comparison analysis of variance can detect a 2% change on samples of 25 cases. Establishing efficacy in individual cases requires a change in feature values on the order of 10 to 15%.
Karyometry provides a sensitive, quantitative method for the assessment of efficacy of chemoprevention. The effects of within-case, biopsy-to-biopsy variance need to be considered only in the evaluation of individual cases, and are on the order of 5% in skin biopsies.
PMCID: PMC2574734  PMID: 18583468
Chemoprevention trials; surrogate endpoint biomarkers; karyometry; sampling variance; power estimates
3.  Weight Change During Chemotherapy as a Potential Prognostic Factor for Stage Iii Epithelial Ovarian Carcinoma: A Gynecologic Oncology Group Study 
Gynecologic oncology  2007;107(2):260-265.
Platinum/paclitaxel-based chemotherapy is a current treatment for advanced epithelial ovarian cancer. We sought to explore the association between weight change during treatment and survival, as well as the association between pre-chemotherapy body mass index (BMI) and survival.
A retrospective data review was conducted of 792 advanced ovarian cancer patients who participated in a phase III randomized trial of cisplatin/paclitaxel versus carboplatin/paclitaxel. Pre-chemotherapy BMI was calculated following surgery. Weight change was defined as the ratio of body weight at completion of protocol therapy to pre-chemotherapy body weight. Progression-free survival (PFS) and overall survival (OS), classified by BMI or relative weight change, were estimated by Kaplan-Meier, and associations were assessed using a Cox model controlled for known prognostic variables (age, race, performance status, histology, tumor grade, tumor residual and treatment group).
There was no association between pre-chemotherapy BMI and survival. There was a significant relationship between median OS and weight change as follows: >5% decrease=48.0 months; 0-5% decrease=49.3 months; 0-5% increase=61.1 months; and >5% increase=68.2 months. Adjusted for covariates, the relative risk of death increased by 7% for each 5% decrease in body weight (HR=0.93, 95% CI=0.88-0.99; p=0.013)
Change of body weight during primary chemotherapy was a strong prognostic factor for overall survival. Loss of body weight during primary therapy is an indicator for poor OS; weight gain is an indicator for improved survival. This study supports the development of strategies to minimize weight loss that can be assessed in a prospective, randomized study to improve patient outcomes.
PMCID: PMC2517223  PMID: 17675142
body weight; BMI; chemotherapy; ovarian cancer; survival
5.  Chemotherapy in advanced ovarian cancer: four systematic meta-analyses of individual patient data from 37 randomized trials. Advanced Ovarian Cancer Trialists' Group. 
British Journal of Cancer  1998;78(11):1479-1487.
The purpose of this systematic study was to provide an up to date and reliable quantitative summary of the relative benefits of various types of chemotherapy (non-platinum vs platinum, single-agent vs combination and carboplatin vs cisplatin) in the treatment of advanced ovarian cancer. Also, to investigate whether well-defined patient subgroups benefit more or less from cisplatin- or carboplatin-based therapy. Meta-analyses were based on updated individual patient data from all available randomized controlled trials (published and unpublished), including 37 trials, 5667 patients and 4664 deaths. The results suggest that platinum-based chemotherapy is better than non-platinum therapy, show a trend in favour of platinum combinations over single-agent platinum, and suggest that cisplatin and carboplatin are equally effective. There is no good evidence that cisplatin is more or less effective than carboplatin in any particular subgroup of patients.
PMCID: PMC2063202  PMID: 9836481
6.  Expression of the zinc finger gene EVI-1 in ovarian and other cancers. 
British Journal of Cancer  1996;74(10):1518-1525.
The EVI-1 gene was originally detected as an ectopic viral insertion site and encodes a nuclear zinc finger DNA-binding protein. Previous studies showed restricted EVI-1 RNA or protein expression during ontogeny; in a kidney and an endometrial carcinoma cell line; and in normal murine oocytes and kidney cells. EVI-1 expression was also detected in a subset of acute myeloid leukaemias (AMLs) and myelodysplasia. Because EVI-1 is expressed in the urogenital tract during development, we examined ovarian cancers and normal ovaries for EVI-1 RNA expression using reverse transcription polymerase chain reaction (RT-PCR) and RNAase protection. Chromosome abnormalities were examined using karyotypes and whole chromosome 3 and 3q26 fluorescence in situ hybridisation (FISH). RNA from six primary ovarian tumours, five normal ovaries and 47 tumour cell lines (25 ovarian, seven melanoma, three prostate, seven breast and one each of bladder, endometrial, lung, epidermoid and histiocytic lymphoma) was studied. Five of six primary ovarian tumours, three of five normal ovaries and 22 of 25 ovarian cell lines expressed EVI-1 RNA. A variety of other non-haematological cancers also expressed EVI-1 RNA. Immunostaining of ovarian cancer cell lines revealed nuclear EVI-1 protein. In contrast, normal ovary stained primarily within oocytes and faintly in stroma. Primary ovarian tumours showed nuclear and intense, diffuse cytoplasmic staining. Quantitation of EVI-1 RNA, performed using RNAase protection, showed ovarian carcinoma cells expressed 0 to 40 times the EVI-1 RNA in normal ovary, and 0-6 times the levels in leukaemia cell lines. Southern analyses of ovarian carcinoma cell lines showed no amplification or rearrangements involving EVI-1. In some acute leukaemias, activation of EVI-1 transcription is associated with translocations involving 3q26, the site of the EVI-1 gene. Ovarian carcinoma karyotypes showed one line with quadruplication 3(q24q27), but no other clonal structural rearrangements involving 3q26. However, whole chromsome 3 and 3q26 FISH performed on lines with high EVI-1 expression showed translocations involving chromosome 3q26. EVI-1 is overexpressed in ovarian cancer compared with normal ovaries, suggesting a role for EVI-1 in solid tumour carcinogenesis or progression. Mechanisms underlying EVI-1 overexpression remain unclear, but may include rearrangements involving chromosome 3q26.
PMCID: PMC2074868  PMID: 8932329
9.  Cimetidine enhancement of cyclophosphamide antitumour activity. 
British Journal of Cancer  1982;45(1):35-43.
Male DBA2 mice were given 10(6) P-388 leukaemic cells i.p. and cimetidine (CMT) at 100 mg/kg 1 day for 10 days, or as a single 100 mg/kg injection 30 min before cyclophosphamide (CTX). CMT significantly prolonged the survival of groups of mice receiving 50, 100 and 200 mg/kg of CTX 3 days after tumour inoculation. Median survival increased by 5.5 days (P less than 0.05), 10 days (P less than 0.05) and 13 days (P less than 0.05) respectively. The addition of CMT had the effect of roughly doubling the CTX dose, without increasing the lethality. CMT produced the only long-term survival seen in the study (1-2/10) CMT alone had no apparent antitumour activity. CMT significantly prolonged mean pentobarbital sleep to 28.6-60 min vs only 10 min for phenobarbital treated mice. Both CMT regimens increased the plasma concentration time products for CTX-induced metabolites (NBP) by about 1.3 fold (in contrast to a 33% reduction with phenobarbital). On average the single-dose CMT regimen produced the greatest effect on survival, on pentobarbital sleep duration and on total NBP reactive species. Probable mechanisms for the CMT-CTX interaction include competitive microsomal enzyme inhibition and/or acutely depressed hepatic blood flow. Caution should be used in combining CMT with full doses of CTX and any other highly metabolized antineoplastic agents in man.
PMCID: PMC2010952  PMID: 7059463
10.  Effect of renal dysfunction in dogs on the disposition and marrow toxicity of melphalan. 
British Journal of Cancer  1981;43(3):330-334.
The effect of renal failure on melphalan pharmacology and toxicity has been poorly understood. Such information is of interest because melphalan is the most commonly used anticancer drug in the treatment of multiple myeloma, which is frequently associated with renal failure. We have studied the disposition and marrow toxicity of parenteral melphalan in dogs before and after induction of renal failure with subtotal nephrectomy. The surgical procedure decreased the creatinine clearance by an average of 62% (P = 0.001). The lowest neutrophil counts following i.v. melphalan (1 mg/kg) averaged 4.9 x 10(3)/mm3 pre-nephrectomy and 0.9 x 10(3)/mm3 post-nephrectomy, respectively (P = 0.002). The mean lowest recorded platelet counts after melphalan (1 mg/kg) were 115 x 10(3)/mm3 in the pre-nephrectomized dogs, and 9.7 x 10(3/mm3 in those who had been nephrectomized (P = 0.002). Following nephrectomy, i.v. melphalan's terminal-phase plasma half-life and renal clearance were both raised (P = 0.02) to 75% over pre-nephrectomy values. These studies show that i.v. melphalan-induced myelosuppression is markedly increased and its plasma elimination and renal clearance significantly decreased in the presence of renal dysfunction in dogs. These data suggest that parenteral melphalan's starting dose be decreased by at least 50% when used in myeloma patients with renal failure.
PMCID: PMC2010602  PMID: 7225283
11.  Antitumour activity and plasma kinetics of bleomycin by continuous and intermittent administration. 
British Journal of Cancer  1980;41(4):644-647.
We have studied the cytotoxicity of bleomycin (4--10 u/kg/day for 6 days) given by continuous i.p. infusion (using an osmotic minipump) compared to daily i.p. bolus administration, against P388 leukaemic spleen colony-forming-units(LCFU-S). Continuous i.p. bleomycin at 8 u/kg/day caused a 0.5 log greater reduction of LCFU-S than did an identical dose given by intermittent bolus administration. The infusion minipump provided constant bleomycin plasma levels of 0.62 +/- 0.03 mu/ml and a total plasma AUC (area under the plasma decay curve) of 89.0 mu.h/ml for 6 days at 8 u/kg/day. Intermittent bolus bleomycin at 8 had a terminal-phase plasma t1/2 of 15 min and a total 6-day plasma AUC of 90.8mu.h/ml. These pharmacokinetic data validate the osmotic minipump as a constant drug-delivery system, and suggest that the two administration schedules resulted in equal total bleomycin dosages. Although high peak bleomycin plasma levels (i.e. 32 mu/ml) were achieved with the intermittent bolus administration, continuous-infusion bleomycin's greater inhibition of LCFU-S was probably related to the drug's schedule-dependent cell-killing characteristics. The results of this study provide further rationale for the continuing use of infusion bleomycin schedules in cancer patients.
PMCID: PMC2010280  PMID: 6155927
12.  Effect of phenobarbital on plasma levels of cyclophosphamide and its metabolites in the mouse. 
British Journal of Cancer  1978;38(2):316-324.
We have studied the quantitative pharmacokinetic differences of individual metabolites and unchanged cyclophosphamide (CPA) in control and phenobarbital-treated animals, using radiolabelled CPA together with thin-layer chromatography. On Day 0, one group was started on phenobarbital drinking water and one group stayed on regular acid water. P388 leukaemia, (10(6) cells i.p.) was administered to all mice on Day 8, and 2 days later both groups of mice were given i.p. CPA (200 mg/kg) with 14C-CPA (0.2 muCi per mouse). At 5--60 min after CPA administration, groups of 10 mice were killed and their blood collected for assay of parent compound and metabolites in plasma. Phenobarbital pretreatment reduced CPA and phosphoramide mustard CXT (concentration x time) by 66+% and 27+%, respectively. Assuming that phosphoramide mustard is both the ultimate cytotoxic form of CPA and the blood-transport form, the reduction of CPA by phenobarbital would predict a decreased therapeutic effect. The assay methods in this study will be used in the future to determine the importance of this potential drug interaction in man.
PMCID: PMC2009716  PMID: 698048
13.  Rubidazone vs adriamycin: an evaluation of their differential toxicity in the spleen colony assay system. 
British Journal of Cancer  1976;34(1):64-68.
Rubidazone, the new semi-synthetic benzol hydrazone hydrochloride derivative of dauorubicin, has proved on a molecular weight basis to be less toxic than adriamycin and similar to daunorubicin in cardiac toxicity studies in the hamster as well as in other in vivo and in vitro test systems. It has proven effectiveness against several animal tumours and human acute leukaemias. We have compared the inhibitory effect of rubidazone to that of adriamycin on P388 leukaemia and normal bone marrow colony-forming units (CFU) using the spleen colony assay system in male DBA2 mice. The efficacy ratios (i.e., the ratio of the slopes of the normal bone marrow CFU to leukaemic CFU dose-survival curves) in the spleen colony assay system for rubidazone and adriamycin were 7-8 and 7-5 respectively. This near identity of efficacy ratios fro rubidazone and adriamycin correlated with the results of median survival time studies in the leukaemic mice. Their dose-median survival time curves were almost parallel, having nearly identical slopes. Rubidazone's equal therapeutic index as compared to adriamycin in the spleen colony assay system together with its known decreased toxicity to cardiac muscle cells makes it an extremely promising new anthracycline derivative to study in comparison to adriamycin in human malignancies.
PMCID: PMC2025119  PMID: 952715

Results 1-13 (13)