Lucie Jeannotte

Prof. Lucie Jeannotte is a regular researcher at CHU de Québec-Université Laval Research Centre, Oncology program, and Professor in the Department of Molecular Biology, Medical Biochemistry, and Pathology of the Faculty of Medicine at Université Laval. She is also a regular researcher at the Centre for Cancer Research at Université Laval. Her research aims to understand the molecular mechanisms involved in the formation of the mammalian embryo, with a specific interest in Hox genes. Hox genes encode transcription factors that play key roles in the developmental hierarchy leading to the pattern formation of the embryo. Loss of Hox gene function in mice results in numerous malformations of skeletons and organs, among others, that can impair survival. The developmental origin of several diseases, including cancer, reveals how important it is to understand the mechanisms that control embryogenesis.

Function of the Hoxa5 gene in the formation of the respiratory system
Lung development implies coordinated regulation of numerous molecules and factors. Prof. Jeannotte and her team have characterized the Hoxa5 mutant mouse line and revealed the critical and unique role of this gene for survival at birth. The loss of Hoxa5 function causes severe defects of the respiratory system that result in the death of mutants at birth. The malformations mimic pediatric congenital diseases, such as tracheal stenosis, lung hypoplasia, and congenital diaphragmatic hernia, as well as chronic obstructive pulmonary diseases (COPD), a major cause of death in the human population. Hoxa5 mutant mice thus provide a unique animal model to further study these pathologies. Prof. Jeannotte is interested in identifying the transcriptional targets of the HOXA5 protein in the respiratory system to define the molecular mechanisms perturbed by the Hoxa5 mutation that underlie the observed phenotypes and may lead to future therapies.

Role of YY1 in the pathogenesis of pleuropulmonary blastoma
Pleuropulmonary blastoma (PPB) is a very rare pediatric lung tumor that arises during fetal life. It results from the progression of abnormal lung cysts to an aggressive sarcoma with poor survival. Prof. Jeannotte’s team has produced mutant mice devoid of Yy1 function in lung epithelium. This mutation causes lung cysts as those seen in PPB patients. YY1 is a transcription factor essential for embryo development and survival. YY1 expression is reduced in PPB lung tumors, raising the hypothesis that the loss of Yy1 function is important for PPB pathogenesis. To determine the role and mechanisms of action of YY1 in PPB, Prof. Jeannotte aims to identify the mechanisms of action of YY1 in lung formation to resolve its implication in PPB formation. These studies may reveal novel molecular targets for designing effective and innovative therapies and better tools for the diagnosis and prognosis of this severe cancer.