DEVELOPMENT OF CELLULAR LINEAGE DERIVED FROM A PATIENT WITH ALL PORTING TRANSLOCATION 8;22 (q24;q11) and DUP (1) (q21;q32).

INTRODUCTION AND OBJECTIVES: During a prospective study of acute lymphoblastic leukemias in childhood, several bone marrow cell samples from patients were placed in culture. One of these samples was able to create an immortal cell line. This work was carried out through experimental descriptive research type Case Study, where several techniques were used, including cariotypic analyses during and after establishment of the lineage, which could identify chromosomal aberrations and the possible implications in the creation of the lineage. The Lymphoblastid Cell Line B called 199 presented t (8;22)(q32;q11) and dup (1)(q21;q32). Our results showed that the cell line 199 originates from FAB L3 b lymphoblastide cell. Karyotypic studies revealed that the cell line 199 carries the karyotype of 53 XY, +X, dup (1)(q21;q32), -4, +6, +7, t (8;22)(q24;q11), +8, +11, +15, +16, +20 deriving therefore from one of the clones originally present in the patient's bone marrow. MATERIAL AND METHODS: During the beginning of the study, several different clones were found. Most of them present ing several chromosomal aberrations: t (1;6)(q21;q23-q26); t (1;11)(q21;p15), t (1;12)(q21;q24); t (1;14)(q21;q32) and t (1;22)(q21;q11). However, these clones did not last long in culture. After the culture was established, cariotypic studies were performed and RNA was extracted from the sample and submitted to RT-PCR reactions to verify the expression of some genes involved with cell immortalization and to identify possible expression alterations. The primers were designed using the sequences already existing in several works already published. RESULTS AND CONCLUSION: It is believed that clone t (8;22) and dup (1), because it presents duplication of chromosome 1 in regions q 21 to q 32, where immortalization genes, such as the CLK-2 gene, were of crucial importance for the creation of the lineage. Other possible explanations are the fact that the presence of translocation t (8;22) also allowed a high expression of genes of genetic transcription factors, such as: Ikaros, NF-EM5, NFAT-1, c-myc, GATA-1 and 2. All involved in hematopoietic development. The c-MYC gene acts directly on cell proliferation, however other samples driving translocation with c-MYC have not been able to become immortal. This type of translocation is estimated to occur in 2% of all Leukemias and Type B lymphomas, including Burkitt Lymphomas. Probably the duplication of chromosome 1 in the regions q21 and q32 allowed the creation of the lineage, because in this region it presents genes that control not only cell proliferation, but are also responsible for regulating telomere size, a very important structure in cell aging. In other studies it was also possible to observe that the duplication of chromosome 1 in regions q21 to q32 are extremely important in the formation of strains being this the main event of transformation and generation of the cell lineage 199.