Targeted inhibition of the JAK/STAT3 pathway inhibits ovarian carcinoma growth

ABSTRACT: Ovarian carcinoma (OC) is the fifth leading cause of death among women in the United States. Persistent activation of signal transducer and activator of transcription (STAT3) is frequently detected in OC. STAT3 is activated by Janus family kinases (JAK) via cytokine receptors, growth factor receptor and non-growth factor receptor tyrosine kinases. Activation of STAT3 mediates tumor cell proliferation, survival, motility, invasion, and angiogenesis, and recent work demonstrates that STAT3 activation suppresses anti-tumor immune responses and supports tumor-promoting inflammation. We hypothesized that therapeutic targeting of the JAK/STAT3 pathway would inhibit tumor growth by direct effects on OC cells and by inhibition of cells in the tumor microenvironment (TME). To test this, we evaluated the effects of a small molecule JAK inhibitor, AZD1480, on cell viability, apoptosis, proliferation, migration and adhesion of OC cells in vitro. We then evaluated the effects of AZD1480 on in vivo tumor growth and progression, gene expression, tumor-associated matrix metalloproteinase (MMP) activity and immune cell populations in a transgenic mouse model of OC. AZD1480-treatment inhibited STAT3 phosphorylation and DNA binding, and migration and adhesion of cultured OC cells and ovarian tumor growth rate, volume and ascites production in mice. In addition, drug treatment led to altered gene expression, decreased tumor-associated MMP activity, and fewer suppressor T cells in the peritoneal tumor microenvironment of tumor-bearing mice than control mice. Taken together, our results show pharmacological inhibition of the JAK2/STAT3 pathway leads to disruption of functions essential for ovarian tumor growth and progression and represents a promising therapeutic strategy. 8 female C57BL/6JTgMISIIR-TAg mice with ovarian tumors of ~500 mm3 were used. 4 vehicle-treated mice (0.5% hypermellose/0.1%Tween 80);4 drug-treated mice (30 mg/kg AZD1480 in 0.5% hypermellose/0.1%Tween 80).

ORGANISM(S): Mus musculus

SUBMITTER: Denise Connolly 

PROVIDER: E-GEOD-63092 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress