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M E vd Burg

Publications and source records attributed to M E vd Burg.

4 recordsLinked to original sources

Sporadic CDKN2 (MTS1/p16ink4) gene alterations in human ovarian tumours.

The cell cycle regulatory proteins p16 and p21 cause cell cycle arrest at the G1 checkpoint by inhibiting activity of cyclin D-CDK4 complexes. The TP53 gene, regulating the p21 protein, is mutated at high frequency in ovarian cancer. The CDKN2 gene, encoding the p16 protein, has been mapped to chromosome 9p21 and encompasses three exons. To establish the frequency of CDKN2 gene abnormalities in ovarian tumour specimens, we have studied this gene in five ovarian cancer cell lines and in 32 primary and five metastatic ovarian adenocarcinomas. Using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and sequencing techniques both exon 1 and 2 of the CDKN2 gene, encompassing 97% of the coding sequence, were analysed. In addition, the TP53 gene was studied for the presence of mutations. The cell line HOC-7 showed a 16 bp deletion in exon 2 of the CDKN2 gene, resulting in a stop codon, whereas in cell line SK-OV-3 this gene was found to be homozygously deleted. Nine primary tumour specimens showed a migration shift on SSCP. Sequencing revealed a common polymorphism (Ala148Thr) in seven of these ovarian tumour specimens. The two other tumour samples were found to contain silent mutations, one at codon 23 (GGT-->GGA) and the other at codon 67 (GGC-->GGT). Mutations in the TP53 gene were observed in 46% of the ovarian tumour specimens. We conclude that CDKN2 gene alterations are rare events in human ovarian cancer. The low prevalence of these alterations do not allow for analysis of an association of this gene with prognosis.

Adenocarcinoma↗

Ifosfamide given as a 24-h infusion with mesna in patients with recurrent ovarian cancer: preliminary results.

The continuous 24-h infusion of ifosfamide (IFX) with mesna was studied in 44 patients with therapy-resistant or relapsing ovarian cancer. All patients had stage III disease and had been pretreated with at least one combination comprising an alkylating agent and a cisplatin analogue (22, with one combination; 16, with two; and 6, with three or more). The median number of IFX cycles received was two. Of 40 evaluable patients, 2 achieved a complete response, 5 showed a partial response and 6 had stable disease. A total of 27 patients had tumor progression after one or two treatment cycles. All seven responders had responded to previous treatment for a median duration of 5 months (range, 5-41 months). No patients who progressed during alkylating-agent treatment responded to IFX given subsequently. The median progression-free period was 6 months (range, 4-12 months), and the median overall survival was only 6 months, indicating the advanced stage of disease in these patients. The median overall survival in progressive patients was 5 months (range 2-13+ months) and that in the remaining group was 13 months (ranges 3(+)-24 months) (P less than 0.05). This treatment was moderately well tolerated. Grade 3 nausea and vomiting occurred in 27% of cycles and grade 3-4 leukopenia was observed in 47%, but thrombocytopenia was hardly ever found. In eight patients there was a deterioration of renal function. Among a total of 131 cycles, the dose was reduced for only 9 due to myelotoxicity and for 3 due to nephrotoxicity. IFX seems to be active only in patients who have relapsed after responding to previous cytotoxic treatment.

Antineoplastic Combined Chemotherapy Protocols↗