Chromosomal translocation t(15; 17) is a specific marker of acute promyelocytic leukemia (APL). In this study, molecular cloning of the t(15;17) breakpoint was carried out in a Chinese APL patient. It has been shown t...Chromosomal translocation t(15; 17) is a specific marker of acute promyelocytic leukemia (APL). In this study, molecular cloning of the t(15;17) breakpoint was carried out in a Chinese APL patient. It has been shown that the retinoic acid receptor alpha (RARA) gene, normally located on chromosome 17, was fused with a new transcription unit PML, normally localized on chromosome 15. We have subsequently cloned a portion of the PML gene and generated a panel of probes. A PML gene rearrangement was detected in 33 out of 36 APL cases studied. 24 rearrangements were clustered in a 4.4 kb region, designated here as PML^(bcr1) whereas 9 rearrangements were concentrated in a 6.5 kb region, defining another breakpoint cluster region (PML^(bcr2)). These two types of rearrangement constitute the basis for the heterogeneity of the PML-RARA fusion gene and its possible biological significance remains to be explored.展开更多
Introduction:Acute promyelocytic leukemia(APL)is mostly due to the chromosome translocation t(15;17)(q22;q12),leading to the formation of PML-RARA fusion protein.Some patients carried rare translocation involving RARA...Introduction:Acute promyelocytic leukemia(APL)is mostly due to the chromosome translocation t(15;17)(q22;q12),leading to the formation of PML-RARA fusion protein.Some patients carried rare translocation involving RARA gene,who were called variant APL caused by RAR family(RARA,RARB,and RARG)and partner genes.STAT5b-RARA was a rare type of molecular genetic abnormality with unfavorable prognosis which have been reported in only 18 cases in variant APL.Knowledge of STAT5b-RARA(+)APL treatment is still limited.Case report:We presented a 38-year-old female variant APL case,who was STAT5b-RARA positive detected by reverse transcription polymerase chain reaction.The patient failed to respond after four-drug combined induction chemotherapy:idarubicin,cytarabine,all trans retinoic acid,and arsenic trioxide(As 2 O 3).Then,the patient was re-induced with azacytidine,but still failed to achieve complete remission(CR).Next,she was treated with Venetoclax combining with homoharringtonine and cytarabine as the salvage therapy and achieved CR.Later,the patient received hematopoietic stem cell transplantation after 4 cycles of consolidation therapy.Conclusion:Venetoclax combining with homoharringtonine and cytarabine has been used as the salvage therapy in the STAT5b-RARA positive APL successfully.展开更多
基金Preject supported by grant from the Chinese Foundation for High Technology (863).
文摘Chromosomal translocation t(15; 17) is a specific marker of acute promyelocytic leukemia (APL). In this study, molecular cloning of the t(15;17) breakpoint was carried out in a Chinese APL patient. It has been shown that the retinoic acid receptor alpha (RARA) gene, normally located on chromosome 17, was fused with a new transcription unit PML, normally localized on chromosome 15. We have subsequently cloned a portion of the PML gene and generated a panel of probes. A PML gene rearrangement was detected in 33 out of 36 APL cases studied. 24 rearrangements were clustered in a 4.4 kb region, designated here as PML^(bcr1) whereas 9 rearrangements were concentrated in a 6.5 kb region, defining another breakpoint cluster region (PML^(bcr2)). These two types of rearrangement constitute the basis for the heterogeneity of the PML-RARA fusion gene and its possible biological significance remains to be explored.
基金The authors would like to appreciate the funding of National Key Research and Development Program of China(2019YFC0840605).
文摘Introduction:Acute promyelocytic leukemia(APL)is mostly due to the chromosome translocation t(15;17)(q22;q12),leading to the formation of PML-RARA fusion protein.Some patients carried rare translocation involving RARA gene,who were called variant APL caused by RAR family(RARA,RARB,and RARG)and partner genes.STAT5b-RARA was a rare type of molecular genetic abnormality with unfavorable prognosis which have been reported in only 18 cases in variant APL.Knowledge of STAT5b-RARA(+)APL treatment is still limited.Case report:We presented a 38-year-old female variant APL case,who was STAT5b-RARA positive detected by reverse transcription polymerase chain reaction.The patient failed to respond after four-drug combined induction chemotherapy:idarubicin,cytarabine,all trans retinoic acid,and arsenic trioxide(As 2 O 3).Then,the patient was re-induced with azacytidine,but still failed to achieve complete remission(CR).Next,she was treated with Venetoclax combining with homoharringtonine and cytarabine as the salvage therapy and achieved CR.Later,the patient received hematopoietic stem cell transplantation after 4 cycles of consolidation therapy.Conclusion:Venetoclax combining with homoharringtonine and cytarabine has been used as the salvage therapy in the STAT5b-RARA positive APL successfully.
