Publications by authors named "Hanna Ala-Hongisto"

Breast cancer is now globally the most frequent cancer and leading cause of women's death. Two thirds of breast cancers express the luminal estrogen receptor-positive (ERα + ) phenotype that is initially responsive to antihormonal therapies, but drug resistance emerges. A major barrier to the understanding of the ERα-pathway biology and therapeutic discoveries is the restricted repertoire of luminal ERα + breast cancer models.

View Article and Find Full Text PDF

Transforming growth factor-beta (TGFβ) is a multifunctional cytokine with a well-established role in mammary gland development and both oncogenic and tumor-suppressive functions. The extracellular matrix (ECM) indirectly regulates TGFβ activity by acting as a storage compartment of latent-TGFβ, but how TGFβ is released from the ECM via proteolytic mechanisms remains largely unknown. In this study, we demonstrate that hepsin, a type II transmembrane protease overexpressed in 70% of breast tumors, promotes canonical TGFβ signaling through the release of latent-TGFβ from the ECM storage compartment.

View Article and Find Full Text PDF

Elevated MYC expression sensitizes tumor cells to apoptosis but the therapeutic potential of this mechanism remains unclear. We find, in a model of MYC-driven breast cancer, that pharmacological activation of AMPK strongly synergizes with BCL-2/BCL-X inhibitors to activate apoptosis. We demonstrate the translational potential of an AMPK and BCL-2/BCL-X co-targeting strategy in ex vivo and in vivo models of MYC-high breast cancer.

View Article and Find Full Text PDF

Breakdown of the basement membrane is a key step that precedes tumor invasion, and accumulating evidence suggests a key role for the type II transmembrane proteases (TTSPs) in that process. Overexpression of a TTSP hepsin characterizes many solid cancers, including prostate, breast, and ovarian cancer, and in experimental tumor models, the elevated proteolytic activity of hepsin simultaneously activates several growth factors and cleaves basement membrane protein laminin-332, which is an essential component of the cell-basement membrane junction hemidesmosome. These hepsin-dependent molecular events associate with dramatic loss of basement membrane integrity in mouse tumor models and in three-dimensional (3D) epithelial culture.

View Article and Find Full Text PDF

Viral diseases remain serious threats to public health because of the shortage of effective means of control. To combat the surge of viral diseases, new treatments are urgently needed. Here we show that small-molecules, which inhibit cellular anti-apoptotic Bcl-2 proteins (Bcl-2i), induced the premature death of cells infected with different RNA or DNA viruses, whereas, at the same concentrations, no toxicity was observed in mock-infected cells.

View Article and Find Full Text PDF