Project Description

By harnessing the inherent ability of facultative anaerobic bacteria to colonize and grow in tumoral environments, this project aims to develop a bacterial cancer therapy. A genetically modified E. coli strain will have knockouts in the lpp and msbB genes, which encode for the Braun's lipoprotein and for the myristic acid moiety transporter of the lipopolysaccharide, respectively. These genes are known to trigger an immune response in the human body; by deleting them, the impact originating from a bacterial intravenous administration will be reduced. Furthermore, these bacteria will produce M13-modified bacteriophages under the control of a quorum sensing system. The resulting phages will be capable of binding to the GRP78 receptor, which is usually overexpressed in cancerous cells. Subsequently, they will internalize and transfect the cancerous cells with two different genes: apoptin, responsible for an apoptotic protein specific for cancerous cells which will be regulated by a constitutive promoter and a survivin siRNA. The latter will inhibit the uncontrollable growth characteristic of cancer cells, making them more vulnerable to apoptosis.

Attenuation

The module talks about the a knockout of two genes of the E. coli endotoxins to attenuate the immunological response of the patients.

Phage engineering

Modifications were made in the phage M13, so it could infect cancerous cells and be produced using Quorum sensing.

Quorum sensing

This system was implemented in the knock-out and is used to cause a coordinated attack from the bacteria that infects the phage.

Effectors

The action of our effectors, apoptin and siRNA, against cancerous cells is explained here.