The University of Hongkong

National Institutes of Health, a Component of the US Dept. of Health & Human Services

Jian-Dong Huang

Lei Shi

Bin Yu

Donald L Court

Nina Costantino

Ye Jin

Julian Alexander Tanner

Xin-tian Li

Depei Liu

Mei Yang

Xin-Mei Zhang

Therapeutic methods for cancer treatments using a combined prokaryotic-eukaryotic delivery and expression system for the delivery of multiple therapeutic factors via a modified tumor-targeted bacteria. A targeted bacteria-vector system elicits an inter-kingdom dual expression (IKDE) of antitumor agents, in the nucleus or cytoplasm of eukaryotic cells, with priming and maintenance of the vector in the bacterium. The therapeutic factors include small interfering RNAs, tumoricidal proteins, DNA molecules, or a combination thereof. The system provides direct killing of tumor cells and alters the tumor microenvironment by expressing anti-angiogenic factors and cytokines in intracellular and/or extracellular environments. Also provided are methods of using natural exosomes comprising cargoes obtained from the bacterially infected cells. The bacteria-vector system is useful for many types of tumor and cancer as well as recombinant vaccines. The method causes significant regression of tumor and prolongs survival of tumor-bearing mice and subject without detectable systemic toxicity.

Therapeutic delivery and expression system, methods and uses thereof

A regulatable gene expression construct comprising a nucleic acid molecule comprising a two-way riboswitch operably linked to a target sequence. Also provided is a library screening strategy for efficient creation of target-specific riboswitches. A theophylline-repressible and IPTG-inducible riboswitch device achieves portable control of gene expression control in a 'two-way' manner. The default state of target genes is ON; the targets are switched off by adding theophylline, and switched back to the ON-state by adding IPTG without changing growth medium. The riboswitch device regulates gene expression in a portable, adjustable, and two-way manner with a variety of scientific and biotechnological applications.

Two-way, portable riboswitch mediated gene expression control device

Described herein is a method of treatment of cancer or tumor using a modified bacteria or composition comprising the modified bacteria. In certain embodiments, the method is in combination with other treatment. In certain embodiments, the treatment is chemotherapy, radiation therapy, gene therapy, surgery or a combination thereof. The method makes modified facultative anaerobic bacteria into a conditional obligate anaerobe. The modified bacteria are strictly hypoxia regulated and comprise an essential gene expressing cassette. The vectors of this method comprise the essential gene expressing cassette. Also described herein are therapeutic and prophylactic compositions comprising the modified bacteria. The therapeutic and prophylactic compositions contain a purified form of the modified bacteria, while in certain embodiments, they do not contain other strain of microorganisms. The modified bacteria grow within the solid tumor/cancer, retarding its growth and are rapidly eliminated from normal tissues. The solid tumor/cancer includes breast cancer, liver cancer or neuroblastoma.

Modified bacteria and their uses thereof for the treatment of cancer or tumor

This invention provides a method for combining overlapping DNA molecules comprising: (a) providing first and second DNA fragments, the first having a region homologous to a region in the second; (b) tagging the first DNA fragment with a selectable marker; (c) cloning the first DNA sequence into a retrieval vector to form a DNA-vector complex; (d) linearizing the DNA-vector complex; and (e) inserting the first DNA fragment from the DNA-vector complex into the second DNA fragment using homologous recombination to form a combined DNA molecule; and (f) removing the selectable marker, thereby generating a combined DNA molecule. The invention further provides a vector for retrieving and inserting a selected DNA molecule into a target DNA molecule.

Method for constructing and modifying large DNA molecules

Methods are disclosed herein for inducing homologous recombination in a host cell comprising a target nucleic acid, using a single-stranded nucleic acid molecule. The single-stranded nucleic acid molecule has a sufficient number of nucleotides homologous to the target nucleic acid to enable homologous recombination with the target nucleic acid. The host cell includes a de-repressible promoter operably linked to a nucleic acid encoding a single-stranded binding protein and is deficient for mismatch repair. Isolated host cells of use in this method are also disclosed.

Growing community of inventors

Hong Kong, China

Jian-Dong Huang