Acute promyelocytic leukemia (APL) represents the first example o f a human cancer successfully treated with a differentiation reducer, all-trans retinoic acid. APL is also characterized by a specific chromosome trans...Acute promyelocytic leukemia (APL) represents the first example o f a human cancer successfully treated with a differentiation reducer, all-trans retinoic acid. APL is also characterized by a specific chromosome translocution t (15; 17). In this work, using techniques of molecular biology, we demonstrated that the gene coding for the retinoic acid receptor alpha (RARA), normally located on chromosome 17, was disrupted by the t (15; 17) and fused with the PML gene on chromosome 15. The chromosome 17 breaks were mapped consistently within the second intron of the RARA gene while the chromosome 15 breaks were clustered in two limited regions within the PML gene. Molecular cloning and sequence analysis of part of the PML gene allowed to establish a specific "nested" reverse transcription/polymerase chain reaction (PCR) procedure to characterize the expression patterns of the PML-RARA fusion gene. Different iso forms of the fusion transcripts were discovered which were produced as a result of distinct PML gene rearrangements. The biological activity of the PML-RARA fusion gene and its iso forms should be further explored.展开更多
Objective: To investigate the distribution and clonality of TCR Vα subfamily T cells in patients with acute promyelocytic leukemia (APL). Methods: The complementary determining region 3 (CDR3) of TCR Vα 29 subfamily...Objective: To investigate the distribution and clonality of TCR Vα subfamily T cells in patients with acute promyelocytic leukemia (APL). Methods: The complementary determining region 3 (CDR3) of TCR Vα 29 subfamily genes in peripheral blood mononuclear cells from 9 APL patients were amplified using RT-PCR. The positive products were further analyzed to identify the clonality of T cells by GeneScan technique. Results: One to seven of TCR Vα subfamilies could be detected in peripheral blood T cells from 9 cases with APL, the frequent expression of Vα subfamilies predominated in Vα3 and Vα19. Clonal expanded T cells could be detected in 8 APL patients, which predominant used Vα3, Vα26 or Vα27 (3 out of 8 cases). However, almost all Vα subfamilies with polyclonal expansion could be detected in peripheral blood T cells from 10 cases of normal individuals. Conclusion: Remarkable skew distribution and clonal expansion of TCR Vα subfamilies T cells is the common feature in patients with APL. Clonal expansion of T cells might reflect a response in host to APL cell as- sociated antigen, whether these expanded T cells have the ability for specific cytotoxicity against APL cells, remains an open question.展开更多
文摘Acute promyelocytic leukemia (APL) represents the first example o f a human cancer successfully treated with a differentiation reducer, all-trans retinoic acid. APL is also characterized by a specific chromosome translocution t (15; 17). In this work, using techniques of molecular biology, we demonstrated that the gene coding for the retinoic acid receptor alpha (RARA), normally located on chromosome 17, was disrupted by the t (15; 17) and fused with the PML gene on chromosome 15. The chromosome 17 breaks were mapped consistently within the second intron of the RARA gene while the chromosome 15 breaks were clustered in two limited regions within the PML gene. Molecular cloning and sequence analysis of part of the PML gene allowed to establish a specific "nested" reverse transcription/polymerase chain reaction (PCR) procedure to characterize the expression patterns of the PML-RARA fusion gene. Different iso forms of the fusion transcripts were discovered which were produced as a result of distinct PML gene rearrangements. The biological activity of the PML-RARA fusion gene and its iso forms should be further explored.
基金Supported by grants from National Natural Science Foundation of China (No. 39870358)Natural Science Foundation of Guangdong Province (No. 2005B50301016).
文摘Objective: To investigate the distribution and clonality of TCR Vα subfamily T cells in patients with acute promyelocytic leukemia (APL). Methods: The complementary determining region 3 (CDR3) of TCR Vα 29 subfamily genes in peripheral blood mononuclear cells from 9 APL patients were amplified using RT-PCR. The positive products were further analyzed to identify the clonality of T cells by GeneScan technique. Results: One to seven of TCR Vα subfamilies could be detected in peripheral blood T cells from 9 cases with APL, the frequent expression of Vα subfamilies predominated in Vα3 and Vα19. Clonal expanded T cells could be detected in 8 APL patients, which predominant used Vα3, Vα26 or Vα27 (3 out of 8 cases). However, almost all Vα subfamilies with polyclonal expansion could be detected in peripheral blood T cells from 10 cases of normal individuals. Conclusion: Remarkable skew distribution and clonal expansion of TCR Vα subfamilies T cells is the common feature in patients with APL. Clonal expansion of T cells might reflect a response in host to APL cell as- sociated antigen, whether these expanded T cells have the ability for specific cytotoxicity against APL cells, remains an open question.
