Transcription of genes of p53-dependent apoptosis in acute leukaemia.

Tumour suppressor protein p53 prevents cancer development through various mechanisms, including the induction of apoptosis. We demonstrated that acute leukaemia, myeloblastic (AML) and lymphoblastic (ALL), is associated with significantly elevated levels of p53 and Bax mRNA in leukaemic cells. Regarding ALL, significantly elevated levels of Bcl-xL mRNA may explain the relative resistance of ALL cells to p53-dependent apoptosis. Altered alternative processing of Bcl-x and myeloid cell leukaemia-1 (MCL1) primary transcripts were observed in the case of AML and AML and ALL, respectively. We assumed that increased glyceraldehyde-3-phosphate dehydrogenase (gapdh) transcription and decreased MCL1s mRNA were not fully responsible for the dysregulation of p53-dependent apoptosis in the case of AML. In addition, transcription of hsp70.1 and Bcl-2 producing anti-apoptotic proteins was not affected in acute leukaemia.