Polymorphism of the proto-oncogene ETS-1 in hematological malignancies.

We studied a novel restriction fragment length polymorphism (RFLP) of the proto-oncogenes ETS-1 that we detected in a patient with an acute monocytic leukemia by the presence of two, 3.7 and 10 kb, Xbal fragments on Southern blots of DNA from blast cells and remission blood samples. RFLP analysis of a series of 114 normal donors revealed that only four (3.6%) shared the 10 kb fragment. By contrast, this unusual allele was found in 20 (all lymphocytic or monocytic) of 108 (18.5%) hematological malignancies (p less than 0.001). DNA sequence analysis indicated the disappearance in the rare allele of a Xbal site due to a single point mutation at the 3' end of ETS-1 locus. Molecular consequences of this mutation point to a possible pathogenic involvement of ETS-1 in these disorders and to the question of genetic susceptibility to hematological malignancies.

The relationship between the cancer cell and the oocyte.

What causes cancer? To date, this question is left with no answer. The scientific community keeps defining cancer as a proliferation of cells in an uncontrolled and uncontrollable manner. The hypothesis developed here through an understanding of the cancer cell's behaviour led to its re-definition, providing answers to the questions arising from cancer. Through striking similarities in cell behaviour, I have concluded that the cancer cell is a reprogrammed cell with the launch of the egg cell's genetic program. The unique cell to express this program is the oocyte, therefore this oocyte cell should become the subject of significant study to understand the genesis of cancer. Above all, it will enable us to eradicate in a specific manner the cancer cell.

Serum, AP-1 and Ets-1 stimulate the human ets-1 promoter.

The ets-1 proto-oncogene codes for a transcription factor. In order to understand how ets-1 is regulated, we have cloned its promoter. We show that the promoter is inducible by serum and expression of c-Fos and c-Jun, and it is positively auto-regulated by its gene product. A 50 base-pair sequence is sufficient to confer c-Fos + c-Jun and c-Ets-1 responsiveness to a heterologous promoter. This element contains two AP1 and one Ets-1 like motifs. Striking, AP-1 and Ets-1 motifs are found in oncogene responsive units (ORU's) of other promoters, suggesting that combining these motifs is a common mechanism for generating mitogen responsive transcription elements.

Splicing with inverted order of exons occurs proximal to large introns.

Following our studies which showed that the alpha and beta exons of the chicken c-ets-1 gene are not conserved in the human homologue, we succeeded in identifying a novel human c-ets-1 transcript in which the normal order of exons is scrambled. By PCR and RNase protection assays, we demonstrated that while the order of exons is different from that in genomic DNA, splicing of these exons in aberrant order occurs in pairs and at the same conserved consensus splice sites used in the normally spliced transcript. The scrambled transcript is non-polyadenylated and is expressed at much lower levels than the normal transcript. It is not the consequence of genomic rearrangement at the ets-1 locus nor is it due to the transcription of any ets-1 pseudogene. These results confirm previous observations of scrambled splicing.