Contact information

Pia Vahteristo,
PhD, Academy Research Fellow

Biomedicum Helsinki 1,
Rm B322b
Haartmaninkatu 8 (PO Box 63)
00014 University of Helsinki

Phone: +358 2941 25600
E-mail: firstname.surname



Tumorigenesis research group


Tumors have traditionally been classified based on tissue of origin and histological appearance. During the last decades, our knowledge on genetic changes in tumors has constantly increased and especially the introduction of next-generation sequencing technology has revolutionized the cancer genetics research. Our lab focuses on identification of novel molecular alterations in tumors and understanding the mechanistic details through which these changes promote tumorigenesis. We are particularly interested in common gynecological neoplasias –uterine leiomyomas, endometrial polyps and endometriotic lesions– and their possible transformation into malignant cancers. We utilize various genome-wide methods such as exome and genome sequencing, genotyping, and global expression profiling. Whenever new potential findings have been discovered their functional effects will be studied with various in vitro experiments.

Another research line focuses on clarifying the role of MED12 in human tumorigenesis. MED12 is part of a Mediator, which is a large, highly conserved protein complex and a key regulator of RNA polymerase II dependent transcription. Very frequent MED12 mutations were first observed in uterine leiomyomas, and recently we identified similar mutations in chronic lymphocytic leukemia. Recurrent MED12 mutations have also been identified in prostate cancer; these mutations are clearly distinct from the mutations observed in leiomyomas and leukemias. We utilize various proteomics and cell biological methods to better understand the functional mechanisms leading to tumor development in various tissue types. These studies are expected to provide new knowledge also on the normal function of MED12 as well as on the Mediator complex in general.