Senior Seminar Summary 1

Riya Shah

Senior Seminar

Dr. Ko

September 22, 2022

Summary

Our first talk of the year was led by Dr. Maryanne Snyder, an Assistant Professor in the

Department of Biological Sciences. Her topic of research was Stat3 and its regulation of Breast

Cancer Metastasis and Cellular Differentiation. STAT3 is a member of the STAT family of

transcription factors. This family includes STAT1, 2, 3, 4, 5A, 5B, and 6. STAT3 plays a role in

immune responses, oncogenesis, differentiation, apoptosis, and proliferation. It is also essential

for embryonic development and is involved in wound healing and lung development. Fascin is a

protein which promotes breast cancer metastasis. It localizes to filopodia, and its functions

pertain to cell adhesion and motility.

The NFkB controls the expression of genes that function in inflammation, cell death, and

tumorigenesis. NFkB binds to specific sites to regulate expression. The NFkB binds to

unphosphorylated Stat3 to form a complex which then regulates a specific subset of target cells.

NFkB p50 binds to the Fascin promoter in response to OSM. In the similar manner, the NFkB

p50 does not find to the Fascin promoter in Stat3 RNAi knock down cells.

Looking more closely at Stat3, it is activated by ligands that bind to the p130 receptor. It

has been noted that activated Stat3 promotes tumor growth and metastasis whereas Stat3

knockdown blocks breast cancer cell migration. The Fascin protein promoter contains a STAT

site in a conserved region. It is active in several forms of cancer. Through the research conducted

by Dr. Snyder, it was concluded that Fascin is a direct Stat3 target gene. With regards to

oncostatin M, Stat3 binds to the Fascin promoter in response to OSM. This means that Stat3 is

activated and Fascin expression increases in 4T1 cells treated with OSM. It was also seen that

breast cancer cell migration is dependent on Stat3. Using invitro assay, which measures cell

migration, it was proven that RNAi mediated Stat3 knockdown cells block cell migration. Stat3

also promotes cardiac differentiation.

Senior Biology Seminar (BIOL 4197)