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N Blin

Publications and source records attributed to N Blin.

147 records · Page 9Linked to original sources

Characterization of a continuous cell line (MHH-NB-11) derived from advanced neuroblastoma.

A continuous cell line was established from an explanted tumor biopsy obtained from a patient with advanced neuroblastoma, which showed no response to chemotherapy. This cell line MHH-NB-11 retained most properties of the original immature tumor, even after xenotransplantation into nude mice. The cell line consisted of small dense cells with scant cytoplasm and thin; long processes and expressed neuron-specific enolase and synaptophysin, but neither GFAP nor S-100 protein. Karyotyping showed karyograms with 49 to 54 chromosomes, with a modal at 52. Most cells had trisomy 2,7,8,20, but only few structural aberrations were observed. Two of four chromosomes 1 showed a rearrangement of the terminal 1p segment, and all cells had a long HSR on the long arm of one of the chromosomes 13. This region hybridized in situ with the N-myc probe pNB-1. N-myc was amplified 20-fold in this neuroblastoma cell line as determined in Southern blot analysis. This cell line should be a useful tool in vitro or as a xenograft model for neuroblastoma research.

Animals↗

Influence of steroid hormones on pS2/BCEI gene expression in xenografted colon tumors.

The biological function of the hormone inducible human pS2/BCEI gene, cloned from the breast cancer cell line MCF-7, still remains unknown. Our aim was to determine the in vivo influence of steroid hormones on pS2 expression and tumour growth in colorectal tumours. We transplanted aliquots of human colon tumours into male and female nude mice and studied tumour growth and expression of the pS2/BCEI gene by immunostaining and mRNA analysis. Our results show that the sex of the host and therefore the hormonal background does not play a dominant role in pS2 expression and growth of the xenografts.

Animals↗

Debrisoquine hydroxylase gene polymorphism in neurofibromatosis type 1.

Cytochrome P450 CYP2D6 polymorphism is an autosomal recessive trait leading to impaired sparteine/ debrisoquine metabolism in 5-10% of the Caucasian population. Previous studies have associated affected individuals (poor metabolizers = PM) with susceptibility to bladder cancer and various forms of leukemia. In many other cancer forms, the data remain contradictory. A PCR assay allows the convenient screening of about 90% of known mutations resulting in the PM phenotype. Since in patients with neurofibromatosis type 2, we had observed a significantly increased rate of CYP2D6 mutations leading to PM and apparently predisposing for NF2, we extended our investigation to tumor and peripheral blood samples obtained from NF1 patients. Although the number of cases investigated remains low, the study indicated that during tumor formation no changes occurred at the mutational hot spot within the CYP2D6 sequence. Moreover, no loss of heterozygosity was notable. However, the frequency of the mutated allele in the NF1 individuals is comparable to that of neurofibromatosis type 2 and above that observed in breast and colon cancer, or meningiomas.

Adolescent↗