Dr. Spencer Gibson, PhD

In maintaining integrity and homeostasis of multicellular organisms, the balance between cell death and survival is fundamentally important. When this balance is altered, diseases such as cancer occur. One protein important in the regulation of cell death is BNIP3 which is induced under low oxygen (hypoxia) conditions and is over expressed in solid tumours. This paradox of BNIP3 killing cancer cells while being over expressed in live cells within tumours is a focus of our research. Three explanations could account for these differences and act as a mechanism for cancer progression.

Cell survival is as important as cell death. The epidermal growth factor receptor (EGFR) is expressed at high levels in several cancers including breast cancer. We discovered that pretreatment of breast cancer cell lines with epidermal growth factor (EGF) effectively blocked drug and death receptor induced apoptosis. This protection from apoptosis is mediated by a serine threonine kinase (AKT) through up-regulation of the Bcl-2 anti-apoptotic family member Mcl-1. Besides breast cancer, we have found that a lipid, lysophosphatic acid (LPA) blocks apoptosis in chronic lymphocytic leukemia (CLL) cells using a similar mechanism. We are currently investigating the regulatory elements controlling Mcl-1 expression.

The goal of my research is to define the signal transduction pathways leading to cell death or survival. This will elucidate targets that could tip balance in favour of cell death and will be the foundation to establish clinical trials using molecular targeted therapies to increase effectiveness of chemotherapy in cancer.

Contact Information:

5008b-675 McDermot Ave
Winnipeg, Mb
R3E 0V9
Phone: 204-787-2051
Email: Dr Spencer Gibson PhD 

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