Le mardi 7 janvier 2025, Monsieur Loïc JOANNES, titulaire d’un Master en Sciences biomédicales à finalité spécialisée (UNamur) et d’un Certificat de formation à la recherche en sciences biomédicales et pharmaceutiques, présentera l'examen en vue de l'obtention du grade de Doctorat en sciences biomédicales et pharmaceutiques, sous la direction de Monsieur Alain COLIGE.

Cette épreuve consistera en la défense publique d'une thèse intitulée : «Antagonistic roles of ADAMTS2 in cancer progression: inhibiting primary tumor growth while being essential for metastatic spread». 

Le jury sera composé de :

Nor Eddine SOUNNI (Président), Michael HERFS (Secrétaire), Alain COLIGE, Yvette HABRAKEN, Elisabeth LETELLIER (Univ. Luxembourg), Carine MICHIELS (UNamur), Nor Eddine SOUNNI.

Résumé de la thèse

ADAMTS2 is an extracellular metalloproteinase involved in fibrillar collagen maturation and lymphatic vessel homeostasis. Exploration of cancer datasets showed that high ADAMTS2 expression in primary tumors is associated with reduced overall survival for several cancer types, suggesting that ADAMTS2 could potentially be a driver of cancer progression. 

Using different mouse models, we have shown that the growth of primary tumor is strongly enhanced in the absence of ADAMTS2 (in ADAMTS2-KO mice versus wild-type), identifying ADAMTS2 as an anti-tumor proteinase. In contrast, the spread of metastases is virtually prevented in ADAMTS2-KO mice, which may explain why high ADAMTS2 expression is of poor prognosis for cancer patients. 

We have also shown that the effect of ADAMTS2 on the primary tumor is not linked to collagen biology or a direct effect on mesenchymal or cancer cells.  Rather, we have demonstrated that tumor-infiltrating immune cells possess a more immunosuppressive polarization in the absence of ADAMTS2, which would explain the increased tumor growth. In vitro, we have also provided evidences that ADAMS2 has direct effect on the differentiation and polarization of macrophages. Our study therefore identifies ADAMTS2 as a key enzyme in the regulation of the immune system during cancer progression.