A genome-wide map showing common regions of loss of heterozygosity/allelic imbalance in breast cancer.

We report here a new framework map that integrates data from 143 studies on the loss of heterozygosity/allelic imbalance in breast cancer. Full details of these loss of heterozygosity maps can be found at the web site (http://www.nottingham.ac.uk/pdzmgh/loh/) that accompanies this report. By combining results from these data, we have also been able to highlight and identify minimum commonly deleted regions on each chromosome. In addition to finding commonly deleted regions at both the BRCA1 and BRCA2 loci, which confirmed the power of the technique, 24 other regions were identified on 16 different chromosomes.

A deletion unit on chromosome 17q in epithelial ovarian tumors distal to the familial breast/ovarian cancer locus.

Linkage analysis in familial breast and ovarian cancer and studies of allelic deletion in sporadic ovarian tumors have suggested that chromosome 17q may be the location of a gene of importance in ovarian carcinogenesis. We have examined tumor and normal DNA samples from 120 patients with ovarian tumors for allelic deletion at 12 loci on chromosome 17q. Allelic deletion was observed in 64 cases (53%) of which 56 showed loss of heterozygosity at all loci analyzed on 17q. The pattern of allele loss at metastatic sites was consistent with loss of heterozygosity having occurred prior to metastasis. A common region of deletion, defined by 6 cases of invasive epithelial ovarian cancer and a benign serous cystadenoma, spanned 16 cM and was delimited by nm23 and GH. This region is distal to the region on chromosome 17q to which the familial breast/ovarian cancer susceptibility gene has been mapped. The results suggest that a tumor suppressor gene involved in sporadic ovarian carcinogenesis is located on the distal portion of chromosome 17q and is distinct from the gene linked to familial cases.

Mutations in the p53 gene in primary human breast cancers.

Twenty-six primary breast tumors were examined for mutations in the p53 tumor suppressor gene by an RNase protection assay and nucleotide sequence analysis of PCR-amplified p53 complementary DNAs. Each method detected p53 mutations in the same three tumors (12%). One tumor contained two mutations in the same allele. Single strand conformation polymorphism analysis of genomic DNA and complementary DNA proved more sensitive in the detection of mutations. Combining this technique with the other two a total of 12 mutations in the p53 gene were demonstrated in 11 tumors (46%), and a polymorphism at codon 213 was detected in another tumor. Loss of heterozygosity on chromosome 17p was detected by Southern blot analysis in 30% of the tumor DNAs. Not all of the tumors containing a point mutation in p53 also had loss of heterozygosity of the remaining allele, suggesting that loss of heterozygosity may represent a later event.

A randomized trial of two etoposide schedules in small-cell lung cancer: the influence of pharmacokinetics on efficacy and toxicity.

PURPOSE: Etoposide is a schedule-dependent drug, as demonstrated by the superiority of 5 consecutive daily infusions over a continuous 24-hour infusion in patients with small-cell lung cancer. A randomized trial has therefore been conducted to compare an extended 8-day regimen with the 5-day schedule. PATIENTS AND METHODS: Ninety-four patients with small-cell lung cancer (35 limited disease, 59 extensive disease) were randomized to receive single-agent etoposide 500 mg/m2, either as 5 daily 2-hour infusions of 100 mg/m2 or as 8 daily 75-minute infusions of 62.5 mg/m2, both repeated every 3 weeks for six cycles. Single-agent carboplatin was administered at relapse in both arms of the study. Patients were stratified at randomization according to extent of disease and Karnofsky performance status (KPS). RESULTS: The overall response rate was 81% in the 5-day arm and 87% in the 8-day arm, with median survival durations of 7.1 and 9.4 months, respectively (no significant differences). The time over which plasma etoposide exceeded low plasma concentrations was significantly longer in patients who responded compared with patients who did not respond. This was most significant for time at concentrations greater than 1, 1.5, and 2 micrograms/mL. Hematologic toxicity was significantly worse in the 5-day arm of the study (cycle no. 1 nadir neutrophil count, 0.8 x 10(9)/L v 1.7 x 10(9)/L). Stepwise regression analysis found duration of exposure to plasma etoposide greater than 3 micrograms/mL to be predictive of nadir neutrophil count and duration of exposure to plasma etoposide greater than 2 micrograms/mL to be predictive of nadir WBC count. CONCLUSION: The 5-day and 8-day regimens had equivalent activity in small-cell lung cancer. A pharmacokinetic association between concentrations of etoposide and response and toxicity was found. Antitumor activity was associated with the maintenance of lower levels of etoposide than found to be associated with hematologic toxicity. This supports the hypothesis that the schedule of etoposide administration may affect efficacy and toxicity, and that prolonged exposure to low concentrations of etoposide may improve the therapeutic ratio for this drug.

A prospective study of 123I-labeled monoclonal antibody imaging in ovarian cancer.

Thirty patients presenting with a pelvic mass were entered into a prospective study on the use of radioimmunoscintigraphy with the 123I-labeled monoclonal antibody HMFG2. The imaging data was obtained without knowledge of the clinical data and compared with subsequent surgical findings. A false-positive diagnosis of ovarian cancer was made in five of ten patients subsequently shown not to have ovarian cancer; thus the technique cannot be used as a screening test. A true-positive diagnosis was made in 19 out of 20 patients shown subsequently to have ovarian cancer. In 18 of these patients the distribution of uptake closely fitted the surgical findings. Methods of improving these results are described. In conclusion, radioimmunoscintigraphy is of no use in determining whether a pelvic mass is due to ovarian cancer, but has benefit in the evaluation of chemotherapy and may, in the future, prevent the need for second-look operations in some circumstances.

A randomized trial to evaluate the effect of schedule on the activity of etoposide in small-cell lung cancer.

Etoposide is an increasingly used and well-tolerated drug in cancer medicine. Its cytotoxic action is phase-specific and it has demonstrated schedule dependency in both in vitro and animal studies, but clinical evidence of the importance of drug scheduling is uncertain. The two administration schedules of etoposide that have been compared in this randomized study of 39 patients with previously untreated extensive small-cell lung cancer treated with single-agent etoposide were 500 mg/m2 as a continuous intravenous (IV) infusion over 24 hours or five consecutive daily 2-hour infusions each of 100 mg/m2. Both regimens were repeated every 3 weeks, for a maximum of six cycles. Patients received combination chemotherapy with vincristine, doxorubicin, and cyclophosphamide (VAC) or radiotherapy on failure to respond or at relapse, depending on their Karnofsky performance status. The same therapy was used in both arms of the study. All patients are evaluable for response to etoposide. In the 24-hour arm, two patients achieved a partial remission, resulting in an overall response rate of 10%. In the 5-day schedule, 16 patients had a partial response and one had a complete remission, producing an overall response rate of 89%, which was significantly superior to that in the 24-hour arm (P less than .001). The median duration of remission to etoposide in the 5-day arm was 4.5 months. Bone marrow toxicity was similar in both schedules. Etoposide pharmacokinetics were measured in all patients, and total areas under the concentration versus time curves (AUCs) were equivalent in both regimens. This study has clearly demonstrated the importance of etoposide scheduling in humans, and the superiority of five daily infusions over a 24-hour continuous infusion. The response rate to single-agent etoposide using an efficacious schedule in extensive small-cell lung cancer has been determined to be in excess of 80%.

Phase I study of etoposide with SDZ PSC 833 as a modulator of multidrug resistance in patients with cancer.

PURPOSE: To determine the maximum-tolerated dose (MTD) and toxicity of PSC 833 infusion administered with etoposide for 5 days in patients with cancer, and to determine the effect of PSC 833 on etoposide pharmacokinetics. PATIENTS AND METHODS: Thirty-five patients were entered onto the study, one of whom was ineligible. Etoposide was delivered from day 1 as a 2-hour infusion over 5 consecutive days at a dose of 75 to 100 mg/m2/d. PSC 833 was administered from day 2 as a 2-hour loading dose and as a 5-day continuous infusion. Doses were escalated from 1 to 2 mg/kg (loading dose) and 1 to 15 mg/kg/d (continuous infusion). RESULTS: Thirty-four patients were treated with 53 cycles of PSC 833 and etoposide. Steady-state blood PSC 833 levels more than 1,000 ng/mL were achieved in all patients treated at PSC 833 doses > or = 6.6 mg/kg/d by continuous infusion. Myelosuppression was the most common toxicity. The major dose-related toxicity of PSC 833 was reversible hyperbilirubinemia, which occurred in 83% of cycles. The dose-limiting toxicity of PSC 833 was severe ataxia, which occurred in two of nine patients treated at 12 mg/kg/d and in both of the single patients treated at 13.5 and 15 mg/kg/d. PSC 833 concentrations more than 2,000 ng/mL resulted in an increase in etoposide area under the curve (AUC) of 89%, a decrease in etoposide clearance (Cl) of 45%, a decrease in volume of steady-state distribution (Vss) of 41%, and an insignificant increase in alpha half-life (t 1/2 alpha) and significant increase of beta half-life (t 1/2 beta) of 19% and 77%, respectively. CONCLUSION: PSC 833 can be administered in combination with etoposide with acceptable toxicity. The recommended continuous infusion dose of PSC 833 for this schedule is 10 mg/kg/d over 5 days. PSC 833 results in an increase in etoposide exposure and etoposide doses should be reduced in patients receiving PSC 833.

Molecular genetic analysis of the von Hippel-Lindau disease (VHL) tumour suppressor gene in gonadal tumours.

Chromosome 3p allele loss is frequent in ovarian and testicular tumours. The von Hippel-Lindau (VHL) disease tumour suppressor gene maps to chromosome 3p25. Gonadal tumours may occur in patients with VHL disease, so somatic VHL gene mutations might be involved in the pathogenesis of sporadic gonadal tumours. To investigate this hypothesis, we screened 60 gonadal tumours (36 ovarian and 24 testicular) for VHL gene mutations and chromosome 3p allele loss. Although 38% (10/26) of informative ovarian and 54% (7/13) of testicular tumours demonstrated 3p allele loss, no somatic VHL gene mutations were detected in the 60 gonadal tumours analysed. This suggested that chromosome 3p tumour suppressor gene(s) other than VHL are involved in gonadal tumorigenesis.

The effect of dose on the bioavailability of oral etoposide: confirmation of a clinically relevant observation.

The effect of dose on the bioavailability of oral etoposide was investigated in ten patients with malignant mesothelioma who received single-agent etoposide as part of a phase II study. Etoposide pharmacokinetics were studied in each patient at oral dose levels of 100, 200, 300, 400 and 600 mg. At doses above 200 mg, the AUC and peak concentrations of etoposide were substantially lower than predictions based on the 100-mg dose. This study confirms previous observations that etoposide absorption is dose-dependent and that a mean bioavailability of approximately 50% cannot be assumed at total oral doses greater than 200 mg.

Cell lines from the melolonthine scarab Antitrogus parvulus.

Continuously replicating cell lines have been established from embryonic tissue and circulating hemolymph cells of the melolonthine Antitrogus parvulus Britton. Isozyme analyses demonstrated that cell lines from both tissue sources expressed essentially the same isoforms of enzymes as A. parvulus larvae and thus confirmed the species of their origin. Karyotype analyses showed that cells from both tissue sources had accumulated changes in chromosome number and morphology during culture. Availability of melolonthine-derived cells should assist in vitro studies of the pathogens of this important group of beetles.

Phase II study of carboplatin and adriamycin as second line chemotherapy in small cell lung cancer.

A total of 25 patients with small cell lung cancer (SCLC) were treated with carboplatin and Adriamycin (CA) following symptomatic relapse after initial therapy, or because of static or progressive disease during primary treatment. Nine patients had disease within the thorax, and 16 had extensive metastases at relapse. The overall response rate to CA was 64% (20% complete response: CR; 44% partial response: PR). Survival from presentation in 22 of the patients who have died was 6-36 months (median 13 months), and the median survival from the commencement of CA was 23 weeks (range 1 week-11.5 months). The duration of CR was 4-8 months, and of PR 2-7 months. Hospital admission was required following 12% of cycles for management of the complications of treatment. The increasing use of first line regimens of short duration means that reassessment should be made of the activity of further therapy at relapse.

Expression profile of FSHD supports a link between retinal vasculopathy and muscular dystrophy.

BACKGROUND: Facioscapulohumeral muscular dystrophy (FSHD) is caused by deletions within a tandem array of D4Z4 repeats on chromosome 4q35. In addition to muscle degeneration, most patients with FSHD develop abnormalities of the retinal vasculature. Previous work has suggested that muscle degeneration in FSHD results from increased expression of genes proximal to the deletion, including FRG1. OBJECTIVES: To reexamine this mechanism and identify pathways that are abnormally regulated early in the disease process. METHODS: We prospectively studied gene expression in skeletal muscle in patients with FSHD (n = 19) vs healthy individuals (n = 30) and patients with myotonic dystrophy type 1 (n = 12). We used oligonucleotide microarrays for global analysis of gene expression and reverse transcriptase-PCR (RT-PCR) to assess expression or alternative splicing for particular genes. RESULTS: Expression of FRG1 was not increased in patients with FSHD, either by microarray analysis or quantitative RT-PCR. Among genes on 4q35, only LRP2BP showed upregulation that was specific to FSHD. However, neither LRP2BP nor FRG1 showed imbalance of allelic expression by RT-PCR. After filtering out genes that showed similar dysregulation in other forms of muscular dystrophy, only 44 genes were specifically upregulated early in FSHD. Among these, 34 genes were characterized or partially characterized, of which 11 (32%) had a role in vascular smooth muscle or endothelial cells. CONCLUSION: Expression of genes on chromosome 4q35 was normally regulated in the early stages of facioscapulohumeral muscular dystrophy. Our results support a possible link between muscular dystrophy and retinal vasculopathy in facioscapulohumeral muscular dystrophy.

Polymerase chain reaction allelotyping of human ovarian cancer.

We have used a set of microsatellite polymorphisms (MSPs) to examine the location and frequency of allele loss throughout the genome in a panel of 25 human epithelial ovarian tumours. When more than one MSP was employed per arm, mean informativity was 85.2% (range 64-100%). The average fractional allelic loss was 0.28 (range 0-0.65). A high frequency of allele loss was seen at 5q (40%), 9q (48%), 11p (43%), 14q (46%), 15q (40%), 17p (61%), 17q (64%), 19p (45%) and Xp (40%), confirming previous findings at some sites, but also suggesting the existence of new tumour-suppressor genes in regions (9q, 14q, 15q) which have not previously been studied in ovarian cancer. For 9q and 14q, partial loss of the arm was more common than loss of heterozygosity for all loci. There was a significant relationship between allele loss affecting the short arm of chromosome 17 and allele loss affecting 17q (P < 0.001). No other relationship was detected between allele losses at different sites. Polymerase chain reaction allelotyping is suitable for the examination of very small tumour samples and tumours in which classical karyotyping is problematic.

Endometrial neoplasia--screening the high-risk patient.

Increased longevity and use of exogenous estrogens appear to have placed more women at risk of developing endometrial carcinoma. Too infrequently, a diagnosis is made in these women at the premalignant stage of their disease. We assessed cytologically, by means of the Milan-Markley helix technique, 170 women seen at our institutions. These patients were classified in one of the following groups: late menstruators, periclimacteric bleeders, women receiving hormone replacement therapy, and women with endometrial pathologic conditions at the time of curettage. The diagnostic accuracy of the helix technique was assessed. Histologic confirmation was obtained with either Vabra or formal curettage. Tolerance on the part of the patient was excellent. Discomfort sufficient to terminate the procedure occurred in two of 189 samples. There were no complications. Tissue adequate for diagnosis was obtained in 180 of 189 samples. Sensitivity was 97%, specificity was 96%, and predictive value of a positive result was 97%. No cases of adenocarcinoma failed to be detected. We conclude that the Milan-Markley helix technique is safe and dependable in assessing women at risk of developing uterine pathologic conditions.

Mapping of the Heliothis armigera entomopoxvirus (HaEPV) genome, and analysis of genes encoding the HaEPV spheroidin and nucleoside triphosphate phosphohydrolase I proteins.

The genome of Heliothis armigera entomopoxvirus (HaEPV) has been mapped with four restriction endonuclease enzymes (BamHI, HindIII, PstI and XhoI), and its length estimated at 233 kbp. An EcoRI-generated HaEPV genomic fragment hybridized to all fragments identified as genomic termini, providing the first experimental evidence for the presence of terminal repeat elements in an EPV genome. The HaEPV spheroidin and nucleoside triphosphate phosphohydrolase I (NPHI) genes have been cloned and sequenced, and their deduced products shown to possess high levels of identity with homologues from other Genus B entomopoxviruses (EPVs). The genomic locations of these and other HaEPV genes and open reading frames have been determined; comparison of their locations with those of homologues in the Amsacta moorei EPV genome largely supports an hypothesis that the Genus B EPVs share a conserved genomic organization which differs from that of chordopoxviruses. It is proposed that genes of EPVs can be assigned to five actual or predicted homology-based groups, a categorization which is useful for directing and interpreting investigations of EPV gene functions and relationships.

Who wants second-line, palliative chemotherapy?

This paper reports on a study designed to measure the value attached to second-line, palliative chemotherapy by people with advanced cancer, compared with the value healthy people assume they would attach if they had cancer and to assess reasons for accepting or declining treatment. Subjects comprised 92 people with cancer, 76 healthy control subjects, 60 medical oncologists, 128 clinical oncologists, 72 palliative care physicians, 58 general practitioners and 59 qualified nurses working within oncology. Using a questionnaire presenting two typical but imaginary treatment scenarios, subjects indicated whether treatment would be acceptable to them and, if so, what minimum chance and duration of benefit would make treatment worthwhile. Demographic and social data were also collected. Patients accepted a lower chance of benefit than all other groups. Although the minimum worthwhile duration of benefit was more evenly spread, patients choosing lower time values were over-represented. These results were consistent even when treatment involved greater toxicity. The conclusion drawn from this study is that people with advanced cancer are more willing to accept second-line chemotherapy with a lower chance and shorter duration of benefit than others may imagine. Health care professionals must recognize this when discussing treatment options with patients.

Morphine intoxication in renal failure: the role of morphine-6-glucuronide.

Patients with impaired renal function may experience severe and prolonged respiratory depression when treated with morphine. This has been attributed to accumulation of the drug during renal failure. Three patients are described who had classical signs of intoxication with morphine in the absence of measurable quantities of morphine in the plasma. The observed clinical effect is attributed to accumulation of the pharmacologically active metabolite morphine-6-glucuronide, which is usually renally excreted. It is concluded that morphine does not accumulate in patients with renal failure but that accumulation of metabolites does occur. The previously reported observations of morphine accumulation during renal failure probably result from the use of radioimmunoassays that cannot distinguish between morphine and morphine-6-glucuronide. Thus the apparent morphine concentration measured with these assays in fact reflects the total quantity of morphine and morphine-6-glucuronide present.

Measurements of resting energy expenditure and body composition before and after treatment of small cell lung cancer.

BACKGROUND: Many patients with small cell lung cancer are reported to lose weight, but the mechanism of this effect is unclear. PATIENTS AND METHODS: Measurements of resting energy expenditure (REE), using indirect calorimetry and body composition (fat, fat-free mass and organ mass), using dual energy X-ray absorptiometry (DXA) and abdominal CT scans were measured in 38 patients with newly-diagnosed small cell lung cancer. Twenty-eight patients were restudied at the end of treatment. RESULTS: In those who responded to treatment there was no change in body weight, but a decrease in REE of 15.7 +/- 11.7 kJ/kg fat free mass/day, whilst in the non-responders body weight decreased 4.33 +/- 5.4 kg, but REE was unchanged. CONCLUSIONS: This study provides evidence for tumour-induced hypermetabolism which is independent of changes in gross body composition, although the absolute increase is small, approximately 0.8 MJ/day. However since body weight was maintained in those patients who responded to treatment either total energy expenditure was decreased, implying decreases in physical activity, or energy intake was increased.

Cardiac arrhythmias during cytotoxic chemotherapy: role of domperidone.

Four patients receiving platinum-containing chemotherapy were treated with domperidone (20 mg) by slow intravenous injection followed by a continuous infusion for 24 h at a dose of 10 mg 24 h-1 kg-1. Cardiac monitoring and plasma potassium and domperidone concentration measurements were performed. Severe cardiac arrhythmias occurred in two patients. A control group of 14 patients treated with similar chemotherapy, without domperidone, also underwent cardiac and plasma potassium monitoring. No significant arrhythmias were seen. The electrophysiologic effects of domperidone are discussed. It is concluded that treatment with intravenous domperidone is associated with the occurrence of cardiac arrhythmias.