Lymphoma is a blood cancer which develops from a type of white blood cells present in the lymphatic system; the lymphocytes. There are two types of lymphocytes: B lymphocytes and T lymphocytes. This study focuses on a particular type of blood cancer affecting T lymphomas, anaplastic large-cell lymphoma. This cancer does not represent more than 2% of all non-Hodgkin’s lymphoma cases but is particularly aggressive. While it can affect people of any age, adolescents and young children are mostjy affected. This lymphoma accounts for 15% of childhood lymphoma cases. In addition, some young patients are chemoresistant and there is no consensus protocol to treated these relapse.
NPM-ALK is an oncogenic protein specific of this cancer, however, clinical studies have shown that its presence is associated with a better prognosis, since the NPM-ALK(+) tumors are mostly chemosensitive. Hoewer, the frequency of relapses suggests that some cells are chemoresistante.
Using high-throughput sequencing technique from a large number of patients, a small non-coding RNA molecule (miR-497) was identified. The presence of miR-497 was NPM-ALK dependant and miR-497 controls the presence of three key regulators of tumor growth. Using a scoring based on the expression of these three regulators, it was possible to identify early chemotherapy relapses of pediatric NPM-ALK(+) T lymphomas.
This study carried out by the team of Fabienne Meggetto, team 7 of the CRCT, and published in the journal Haematologica is a promising track for improving the chemotherapy response and developing a new biotool to predict the response of chemotherapy.
This work was carried out in partnership with the Toulouse CHU and the CRCT. It was supported by the TOUCAN Labex, the Carnot Lymphoma/CALYM Institute, the Fondation ARC, the Ligue contre le Cancer (Equipe labellisée LIGUE 2017)
Discover the article :
Haematologica. 2019 Feb;104(2):347-359.
miR-497 suppresses cycle progression through an axis involving CDK6 in ALK-positive cells.
Hoareau-Aveilla C, Quelen C, Congras A, Caillet N, Labourdette D, Dozier C, Brousset P, Lamant L, Meggetto F.
Key word :
- Cancer / T Lymphoma
- on-coding RNA
Team 7 – CRCT