Les gliomes malins prolifèrent d’une manière très anarchique et elles s’infiltrent dans le parenchyme cérébral. Plusieurs facteurs de croissance, tels que le Transforming Growth Factor Beta (TGF-ß), sont surexprimés dans les gliomes malins. La voie de signalisation du TGF-ß joue un rôle clé dans la régulation des mécanismes liés au métabolisme et à la prolifération cellulaire. L’objectif principal de cette étude est d’évaluer les effets de l’inhibition de la voie de signalisation du TGF-ß sur le phénotype des gliomes malins. Deux méthodes ont été utilisées pour inhiber la voie du TGF-ß. La première est un traitement à la chloroquine, un agent alcalinisant lysosomotropique, qui module à la hausse le pH du Trans Golgi Network (TGN )/endosome. Cet agent inhibe la furine, une protéase nécessaire à la maturation du TGF-ß, ainsi que la métalloprotéases-2 (MMP-2) qui permet la libération du TGF-ß de la matrice extracellulaire (MEC). La deuxième méthode est un traitement avec l’Avasimibe™, un agent qui inhibe l'Acyl-CoA-Acétyltransférase (ACAT) démontrée comme étant activé par le TGF-ß. Les effets de ces deux agents ont été testés sur la sécrétion de TGF-ß, sur le métabolisme et la prolifération cellulaire de la lignée de gliomes murins F98. Par l’immunobuvardage de type Western blot, notre étude a révélé la présence de la forme immature de TGF-ß1 et de Latency Associated Peptide (LAP) dans le surnageant de la lignée de gliomes murins F98. Par le test Enzyme Linked Immunosorbent Assay (ELISA), l’étude a indiqué que la chloroquine et l’Avasimibe™ diminuent de 85 ± 3 % et 65 ± 1 % la concentration de TGF-ß1 mature sécrétée dans le surnageant cellulaire. Les essais WST-1 et BrdU ont montré que des expositions de 24 h et 48 h à la chloroquine et l’Avasimibe™ diminuent significativement de plus de 74 ± 9 % et 86 ± 2 % % le métabolisme et la prolifération cellulaire. La zymographie pousse à croire que les effets de chloroquine étaient associés à une inhibition de 75 ± 1 % de l’activité de la MMP-2 en 48 h. L’ajout de la chloroquine et de l’Avasimibe™ pourrait être bénéfique au traitement standard des gliomes malins en réduisant leur phénotype.

Idiopathic pulmonary fibrosis (IPF) is an interstitial lung disease of unknown etiology, in which excessive accumulation of scar tissue in the interstitial spaces of the lung obstruct normal pulmonary function. Currently, the only curative treatment is lung transplantation. While pharmaceutical therapeutics have been recently approved for use in IPF in 2014, they are still unable to provide a truly curative treatment. While genetic risk factors have been identified, the most commonly occurring mutation is only detected in approximately 38% of IPF patients, leaving an uncertainty in the very existence of a common genetic factor in IPF. Cigarette smoke and other environmental particulates have been significantly linked to the diagnosis of IPF, implicating an initial immunological response to trigger the pathogenesis of IPF. Nintedanib, a potent tyrosine kinase receptor inhibitor was first developed in 1998 as a candidate for cancer treatment. Investigation of its effects in fibrosis in the past few decades has led to a significant discovery of its application in IPF. Nintedanib significantly inhibits the fibrotic activity of fibrotic myofibroblasts in the lungs by inhibiting signaling cascades necessary for cell proliferation and progression of the disease. However, nintedanib falls short in that it cannot fully inhibit the advancement of the disease and mortality rates of IPF still remain high. Pirfenidone, the other currently available pharmaceutical therapeutic, was discovered in 1976 as a potent inhibitor of inflammation. Subsequent experiments further reviled its potency as an anti-fibrotic drug. After decades of research, pirfenidone’s mechanism of antifibrotic characteristics were revealed as a potent inhibitor of fibrocyte recruitment and chemotaxis, and as an inhibitor of transcription growth factor beta (a growth factor heavily implicated in the activity of myofibroblasts) mediated pathways. However, like nintedanib, pirfenidone fails as a curative treatment, only delaying the progression of the disease. In the search for new molecular targets for pharmaceutical therapy, forkhead box M1 (FOXM1), programmed cell death protein-1 (PD-1), and prostaglandin E2, have been identified to play a mediatory role in many of the pathways involved in myofibroblast activity. Many of these targets have also been identified in other disease models such as cancer and immunological inflammatory disease. Avasimibe has been recently identified as a potent inhibitor of aldo-ketoreductase through a FOXM1 mediated pathway. Its molecular mechanism in osteosarcoma cancer disease model may prove to be a novel pharmaceutical therapeutic for IPF. BI 853250, a novel focal adhesion kinase (FAK) inhibitor also demonstrates potential to be a new pharmaceutical therapeutic for IPF patients. Exploring signaling pathways that involve these newly found targets and collaborative research with cancer and immunological diseases shows promise in providing steps to cure IPF in the future.