Question

What is the advantage of using double negative 3 cells (DN3) cells to analyse gene expression using real time PCR in leukemia research?

Answer 1

T-cell leukemia is a hematological malignancy characterized by abnormal proliferation of immature T-cells in the thymus.

Maturation of T-cells happens in the thymus. During the maturation and differentiation of T-cells in the thymus, there are multiple stages such as Double negative stage (DN1), DN2, DN3, and DN4.

DN3 cells are committed cells which means they don't have self-renewal capacity and will undergo differentiation into mature T-cells.

In order to induce leukemia in mouse models, research groups have expressed oncogenic genes and observed increased expansion of immature DN3 cells. These DN3 populations contain Leukemia-initiating cells (LIC) which can generate leukemia in transplanted mice.

Multiple other groups also showed that expression of oncogenes resulted in increased LIC population in DN3 population.

All these studies suggested that DN3 cells attained self-renewal, stem cell-like properties. They also suggest that at DN3 cell stage is the crucial stage of leukemia development,

Thus, Studying the regulation of transcription in DN3 cells will give important information regarding how uncontrolled proliferation is induced in these cells and which genes play a key role in the transformation of DN3 cells to tumor cells.