Using Bacteria as a Drug Delivery Device for Cancer Treatments

Salmonella typhimurium has been shown to have tumor suppressing effects with a knock out of the genes msbB and purI loci, creating the strain VNP20009. In my research, I will be assessing the possibility of additional knockouts and mutations within the VNP20009 genome to be used as a targeted delivery for tumor-suppressing agents that are safe for use preclinical trials.

I will be observing the invasion of VNP20009 in monolayer cultures of human breast adenocarcinoma cell line (MCF7) and comparing this to a strain of VNP20009 that has the SipB gene knocked out so that it is unable to function. The primary role of the SipB gene in VNP20009 is to aid in the invasion of host cells via an arm-like structure that is able to latch onto other cells and transfer its proteins to the host cells as a means of intercellular replication. However, the SipB gene is not responsible for the secretion of proteins, so this process will not be interrupted with the SipB knockout. It is hypothesized that the SipB knockout within the bacteria will reduce its invasion in cells, making it a safer cancer treatment by not latching onto and invading healthy cells surrounding the cancerous tissue. This will be quantified by transforming green fluorescent protein (GFP) into VNP20009 with and without the SipB knockout to visually record the cellular invasion in MCF7 under a fluorescent microscope.