Although this is ‘my thesis’, I am proud to say that the research presented in it was a joint effort of many people. I have had the pleasure to work with many supervisors, mentors, collaborators and helpful colleagues. In this section I would like to thank everyone that has contributed to the creation of this thesis, in English, so everyone will be able to read how grateful I am for all the help!

KWF (Dutch Cancer Society)
Without the KWF grant written by Adrian Begg, Frank Hoebers and Michiel van den Brekel it would not have been possible for me to have started this research at the NKI.

Thesis supervisors (promotores)
Prof. dr. Marcel Verheij and prof. dr. Michiel W.M. van den Brekel: thank you for the useful discussions, your quick responses to new versions of papers and your support throughout the years. It has been a pleasure to work with both of you!

Thesis co-supervisor (copromotor)
Prof. dr. Hein te Riele: thank you for taking over after Adrian died and for helping me out with your useful comments during the analyses and writing of chapter 4 and 5.

Thesis committee
I would like to thank the members of the thesis committee for taking the time to read this thesis and for their willingness to take part in it’s defence: prof. dr. Ruud H. Brakenhoff, dr. Conchita Vens, prof. dr. J.H. Kaanders, prof. dr. Chris H.J. Terhaard, prof. dr. Johannes (Hans) A. Langendijk and dr. Marie-Louise F. van Velthuysen.

Other supervisors
Dr. Frank J. Hoebers and prof. dr. Coen R. N. Rasch: thank you for initiating this line of research. I have always appreciated your supervision, comments and suggestions and was very sorry you went to work at other institutes before the project was finished.
Dr. Marie-Louise (Loes) F. van Velthuysen: without the hours you spent behind the microscope to check my slides for tumor cells and CD44 staining percentage we would have been nowhere. Thank you for good conversations while teaching me the basics of pathology.
Prof dr. Alfons J.M. Balm and dr. Jan Paul de Boer: thank you for joining our lunch meetings with useful comments and suggestions.

Laboratory (divions of ‘Experimental therapy’ and ‘Biological stress response’)
It has always been wonderful to be a member of the ‘Begg group’. I would like to thank all the previous members for the pleasant collaboration.
Dr. Jimmy Pramana: you did all the hard work in the years before I came to the NKI. Thank you for letting me take over and kickstarting my project.
Dr. Sari Neijenhuis: you took me by the hand when I first came to the lab, taught me how to pipet, do a PCR and how to treat my cells ‘like they were my children’. I am glad you started your big sister duties on H6, but even happier you didn’t stop them after finishing your PhD.
Dr. Conchita Vens: thank you so much for teaching me. I have learned a lot from you, from your sharp questions to teaching me about mycoplasma and retroviral work.
Manon Verwijs and Ingrid Hofland: thank you for all the support. It was great to work with both of you.
Sometimes I have wondered why they let a medical doctor in the lab. When I first started I did not know any laboratory techniques. A lot of people from different departments have been very patient in explaining things to me and answering all the questions I had. With a special thanks to: Linde Braaf, Hans Halfwerk, Hans te Poele, Renske Fles, Marleen Kok, Ben Floot, Josien de Bois and Thea Eggenhuizen.

Collaborators and co-authors
I am  grateful for the collaboration with many co-authors. I would like to especially thank all co-authors of chapter 3, it was hard to obtain fresh frozen material of small larynx carcinomas. Thank you for being willing to collaborate and having me in your institute with my box of dry ice to collect the material.
Professor Reidar Grénman and Leila Reunanen: thank you for the fruitful collaboration. The visit to your lab was very helpful. Thank you for sharing so many cell lines and data with us.
Prof. dr. Ed M.D. Schuuring and dr. Jacqueline E. van der Wal: it was a pleasure to collaborate with you. Thank you for sharing your ideas, data and time with us.

NKI-AVL Bioinformatics department
Jelle ten Hoeve: the collaboration with you took my R skills to a new level. Without you chapter 3 would have looked very different. Thank you for helping me find a website name and suggesting I use WordPress software to make this website, it made life much easier.
Prof. dr. Lodewyk F. Wessels, dr. Sander Canisius and dr. Michael Hauptmann: thank you for providing us with bioinformatical support and suggestions for study designs.

NKI-AVL Genomics core facility (formerly known as the Microarray facility)
Dr. Ron Kerkhoven: I would like to thank you and your group for the excellent microarray, sequencing and bioinformatics support.
A special thanks to Mike Heimerikx, Wim Brugman, Janneke Kruizinga, and Marja Nieuwland for conducting many experiments and to Daoud Sie, Arno Velds and Iris de Rink for helping out with bioinformatical problems.

NKI-AVL Core facility molecular pathology and biobanking
Dr. Annegien Broeks, Dennis Peters and Linde Braaf: thank you for supplying NKI-AVL Biobank material and laboratory support.

NKI-AVL Department of radiation oncology
All colleagues at the department of radiation oncology: thank you for allowing me to combine research with clinical work and for taking over work while I was on research time.

Professor Rob Bristow and professor Padraig Warde: thank you for mentoring a fifth-year medical student and introducing her to the unknown world of radiobiology. Without you, my career would have been very different.
Prof. dr. Harry Bartelink: thank you for allowing me to perform my research in Adrian Begg’s group. It has been very motivating to try to prove to you I made the right decision after all.
Professor Paul M. Harari and professor Michael Baumann: your support has been very special to me. I hope I will one day be able to motivate a young PhD student like you did for me.
Dr. Fiona A. Stewart: thank you for being a great example, for adopting an ‘orphan’ PhD student, for proofreading this thesis, but most of all for your never-ending support and friendship.

Dr. Annemarie de Vries: dear Annemarie, you have already given me the perfect example. All I have to do now is follow in your footsteps. I am glad you’ll be by my side during my defence.
Marieke van Eenennaam: dear Marieke, you are always there for me and manage to put things into perspective. Of course I want you by my side during my defence.

Colleagues, family and friends
During my time at the NKI-AVL I have worked in a lot of different departments. I am happy to say that I found great colleagues and friends in all of them. Thank you for making work such a pleasant place to be!

Dear family and friends, thank you for your interest in my research and your support along the way. I would like to especially thank my parents and brothers Maarten and Bart for always and unconditionally being there for me. Thank you for being who you are and letting me be who I am. You’re the best!

Thank you!