
 
 
 Proposition de sujet de thèse à l’appui d’une demande de contrat doctoral 2017-2018 
 
Nom, prénom du directeur de l'unité de recherche : BALDACCI Giuseppe 
Numéro de l'unité de recherche (et établissement de rattachement) : Institut Jacques MONOD UMR 
7592 CNRS Université Paris DIDEROT – Paris 7. 
Nom, prénom du responsable de l'équipe d'accueil (EAD) : BALDACCI Giuseppe 
Nom, prénom du directeur de thèse : CADORET Jean-Charles, FAUCHEREAU Fabien (co-directeur)  
Titre du sujet de thèse proposé : Molecular study of the mechanisms of action of CDK4 and CDK6 
inhibitors on adrenocortical carcinomas 
Citer 5 mots clés : cancer, DNA replication, therapeutical targets, drug combination, 
Bioinformatics 
Candidat pressenti :    OUI          NON   
 Contenu scientifique du programme de la thèse 
Adrenocortical carcinomas (ACCs) are deadly cancers with limited opportunities of treatment. We 
studied  transcriptomic  data  generated  from  adrenocortical  tumors  by  "The  Cancer  Genome  Atlas" 
consortium (TCGA). Our study was focused on the expression levels of 136 genes involved in the G1/S 
phase transition and DNA replication. Correlation of mRNA levels with clinical data showed that high 
gene expression of CDK6 was associated with a short time to relapse and death. Thus we tested the 
impact of CDK4 and CDK6 inhibitors (namely palbociclib and ribociclib) on cell viability of the NCI-H295R 
and SW-13 cell lines, which were derived from ACCs. Both drugs decreased cell viability of the ACC-
derived  cell  lines  and  are  possible  candidates  for  clinical  testing.  Reduction  of  cell  viability  was 
associated  with  aberrant  cell  cycle  and  senescence.  Our  observations  also  prompt  us  to  explore 
palbociclib effect on epithelio-mesenchymal transition (EMT), and autophagy. 
Since  previous  cell  cycle  analyses suggested abnormal  DNA  synthesis  during  S-phase  after 
treatments, a precise profile of DNA replication timing-program will be generated on treated cells. The 
PhD  student  will  also  study  the  impact  of  palbociclib  and  ribociclib  on  EMT  by  assessing  cellular 
adherence, migration and invasiveness of NCI-H295R and SW-13 cells. He/she will test their impact on 
cellular pathways that are involved in  EMT  (-catenin, cadherins and vimentin). Since  autophagy  is 
involved in  several cellular  processes  that may either facilitate  or  suppress tumorigenesis, including 
secretion  of  steroid  hormones,  the  student  will  measure  autophagy  after  treatments  with  either 
palbociclib or ribociclib. Hormone secretion will also be assayed on hormone-secreting NCI-H295R cells.  
Second,  the  student  will  test  on  NCI-H295R  and  SW-13  cell  lines  the  possible  synergic 
interactions  between  ribociclib  or  palbociclib  and  other  anti-cancer  drugs.  Such  combinations  can 
potentiate the effects of drugs and reduce the concentration needed to reach therapeutic benefits.  After 
treatment of cells with combined drugs, their impact on cell viability will be tested. Further analyses will 
be performed on mouse xenograft models, in collaboration with other groups. 
Finally, the bioinformatic approach mentioned above brought fresh perspectives to our research 
and we will extend these analyses to all the cancers studied by TCGA. To achieve this, clusters of 
cancers will be defined, based on mRNA levels of genes involved in DNA replication (such clusters may 
include cancers affecting different tissues). Clinical (time of relapse-free survival, or overall survival) and 
molecular (mutation rate, chromosomal abnormalities) features between groups will then be compared. 
This approach will result in a more integrative perspective of DNA replication in cancer. The scientific 
staff of our research group will teach to the student the bioinformatic tools needed for this project. 
 
Indiquez les cinq meilleures publications récentes de l’équipe : 
1. Fauchereau F, Shalev S, Chervinsky E, Beck-Fruchter R, Legois B, Fellous M, Caburet S, Veitia RA. A non-
sense MCM9 mutation in a familial case of primary ovarian insufficiency. Clin Genet. 2016 May;89(5):603-7. 
2. Hadjadj D, Denecker T, Maric C, Fauchereau F, Baldacci G, Cadoret JC. Characterization of the replication 
timing program of 6 human model cell lines. Genom Data. 2016 Jul 15;9:113-7. 
3. Baldacci G, Hoffmann JS, Cadoret JC. Impact of the DNA polymerase Theta on the DNA replication program. 
Genom Data. 2014 Dec 5;3:90-3. 
4.  Maric  C,  Bénard  M.  Replication  forks  reverse  at  high  frequency  upon  replication  stress  in  Physarum 
polycephalum. Chromosoma. 2014 Dec;123(6):577-85. 
5. Fernandez-Vidal A,* Guitton-Sert L,* Cadoret JC,* Drac M, Schwob E, Baldacci G, Cazaux C, Hoffmann JS. A 
role for DNA polymerase θ in the timing of DNA replication. Nat Commun. 2014 Jul 3;5:4285. (* co-first authors)