Vallenius lab

Contact information

Tea Vallenius MD, PhD
Principal Investigator
Academy research fellow
Tel. +358 2 941 25571
Fax. +358 2 941 25610

Biomedicum Helsinki 1
P.O.Box. 63, (Haartmaninkatu 8)
00014 University of Helsinki



Roles of actin fibers in regulating E-cadherin and integrin based adhesions

90% of cancer mortality results from the dissemination of cancer cells from the primary tumor to secondary sites. To disseminate, cancer cells acquire an efficient remodelling ability to migrate over tissue boundaries. The E-cadherin and integrin complexes and their associated actin fibers at cell-cell and cell-extracellular matrix junctions represent major remodeling sites. In some invading cancers E-cadherin is lost, but in others E-cadherin function perturbs through uncharacterized mechanisms, where actin fibers and their regulators have been implicated. Our main interests include the characterization of the molecular composition of E-cadherin-associated actin fibers and the investigation of their contribution to invasion in cancer cells. The approach takes advantage of data mining approaches in various cancer related databases. To investigate how various candidate proteins regulate E-cadherin adhesions, we are developing assays to elucidate dynamics of E-cadherin – actin signaling. Using both in vitro and in vivo assays we aim to narrow down critical regulators for cancer cell migration and invasion.
Another research interest involves the characterization of the molecular composition of actin stress fibers subtypes associated with integrin-based adhesions and their functional significance in mesenchymally migrating cells. Our recent results demonstrate striking molecular and functional differences between dorsal stress fibers and other actin stress fiber subtypes (Kovac et al., jCS 2013). We are currently extending these initial results to other models and establishing screening strategies to further characterize molecular and functional differences between actin stress fiber subtypes.