1/4. p53 intronic point mutation, aberrant splicing and telomeric associations in a case of B-chronic lymphocytic leukaemia.We report a case of chronic lymphocytic leukaemia (CLL) with telomeric associations and a p53 intronic point mutation. Karyotypic analysis revealed clonal and non-clonal telomeric associations, accompanied by clonal cytogenetic abnormalities and also in isolation. The p53 mutation, which occurred at the invariant base pair -2 of the splice acceptor site in intron 7 resulted in the abolition of correct splicing of exon 7 to exon 8. Multiple aberrant splice products were characterized, all of which differed from wildtype in the dna binding domain. fluorescence in situ hybridization demonstrated that the clone retained two copies of the p53 gene and wild-type p53 transcript was detected on cloning of reverse transcriptase polymerase chain reaction (RT-PCR) product, indicating that one wild-type allele remained. However, a plasmid clone with correct splicing at the exon 7/8 boundary, but with a 21 bp deletion in exon 8, was also found at low frequency. This finding indicates clonal evolution, resulting in complete loss of wild-type p53. The intronic point mutation was not present in dna extracted from cervical tissue indicating that it was a leukaemic phenomenon. This is the first case of an intronic point mutation to be reported in CLL. This mutation led to chaotic p53 expression and, interestingly, occurred in a case showing telomeric associations, a rare phenomenon in B-CLL.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/4. The therapy of virus-associated epithelial tumors of the face and the lips in organ transplant recipients.The risk of developing malignant cutaneous neoplasms is increased after organ transplantation. We report three patients with malignant tumors of the epithelium of the facial skin and the lips after kidney and heart transplantation, respectively. They showed an aggressive course of the disease with more than five synchronous or metachronous basal cell and squamous cell carcinomas. Tissue samples were Epstein-Barr virus (EBV) positive by PCR. Using an in situ hybridization technique EBV-encoded rna (EBER) was detected in tumor-infiltrating lymphocytes. The aggressive course was not alone controllable by surgical or radiological therapy. The systemic and topical application of cidofovir (Vistide) led to remarkable remissions, to a better confinement and operability of the tumors, and to a cessation of tumor pain. The photodynamic therapy represents another opportunity for managing superficial local recurrences and multiple tumors. In conclusion, the results of these case reports demonstrate that combined antiviral, photodynamic and surgical therapy may be used successfully to treat aggressive cutaneous malignancies in patients after organ transplantation.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/4. Infantile condylomata of the oral cavity.A child had condylomata acuminata localized to the oral cavity. Main points of interest were this exclusive localization, the extremely high number of papillary lesions, not reported in the literature until now, and the excellent response to interferon and local applications of podophyllin. Histologic, ultrastructural, and in situ molecular hybridization techniques were performed to make a correct diagnosis. Transmission of the etiologic agent and therapeutic approaches are discussed.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
4/4. Recurrent oral condylomata acuminata and hairy leukoplakia: an early sign of myelodysplastic syndrome in an HIV-seronegative patient.Oral hairy leukoplakia (OHL) has been observed in all risk groups seropositive for HIV infection. Recently, this lesion has also been described in HIV-seronegative patients with immunosuppression of iatrogenic origin. We report on a hiv-1 and hiv-2 seronegative, heterosexual man affected by refractory anemia with ringed sideroblasts (myelodysplastic syndrome), who developed recurrent oral condylomata acuminata and OHL as an early clinical manifestation. The diagnosis of OHL was confirmed by identifying Epstein-Barr viral particles by electron microscopy and by in situ dna hybridization. HIV infection was ruled out using polymerase chain reaction and testing for hiv-1 and hiv-2 antibodies.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |