PPFIA1 is located at the 11q13 region, which is one of the most
commonly amplified regions in several epithelial cancers including head
and neck squamous cell carcinoma and breast carcinoma. Considering the
location of PPFIA1 in this amplicon, we examined whether protein encoded by PPFIA1,
liprin-α1, possesses oncogenic properties in relevant carcinoma cell
lines. Our results indicate that liprin-α1 localizes to different
adhesion and cytoskeletal structures to regulate vimentin intermediate
filament network, thereby altering the invasion and growth properties of
the cancer cells. In non-invasive cells liprin-α1 promotes expansive
growth behavior with limited invasive capacity, whereas in invasive
cells liprin-α1 has significant impact on mesenchymal cancer cell
invasion in three-dimensional collagen. Current results identify
liprin-α1 as a novel regulator of the tumor cell intermediate filaments
with differential oncogenic properties in actively proliferating or
motile cells.