Selectively Suppressing Tumor Angiogenesis for Targeted Breast Cancer Therapy by Genetically Engineered Phage

Antiangiogenesis is a promising approach to cancer therapy but is limited by the lack of tumor-homing capability of the current antiangiogenic agents. Angiogenin, a protein overexpressed and secreted by tumors to trigger angiogenesis for their growth, has never been explored as an antiangiogenic target in cancer therapy. Here it is shown that filamentous fd phage, as a biomolecular biocompatible nanofiber, can be engineered to become capable of first homing to orthotopic breast tumors and then capturing angiogenin to prevent tumor angiogenesis, resulting in targeted cancer therapy without side effects. The phage is genetically engineered to display many copies of an identified angiogenin-binding peptide on its side wall and multiple copies of a breast-tumor-homing peptide at its tip. Since the tumor-homing peptide can be discovered and customized virtually toward any specific cancer by phage display, the angiogenin-binding phages are thus universal "plug-and-play" tumor-homing cancer therapeutics.

Enhancement of Photodynamic Cancer Therapy by Physical and Chemical Factors

The viable use of photodynamic therapy (PDT) in cancer therapy has never been fully realized because of its undesirable effects on healthy tissues. Herein we summarize some physicochemical factors that can make PDT a more viable and effective option to provide future oncological patients with better-quality treatment options. These physicochemical factors include light sources, photosensitizer (PS) carriers, microwaves, electric fields, magnetic fields, and ultrasound. This Review is meant to provide current information pertaining to PDT use, including a discussion of in vitro and in vivo studies. Emphasis is placed on the physicochemical factors and their potential benefits in overcoming the difficulty in transitioning PDT into the medical field. Many advanced techniques, such as employing X-rays as a light source, using nanoparticle-loaded stem cells and bacteriophage bio-nanowires as a photosensitizer carrier, as well as integration with immunotherapy, are among the future directions.

Efficient Phage Display with Multiple Distinct Non-Canonical Amino Acids Using Orthogonal Ribosome-Mediated Genetic Code Expansion

Phage display is a powerful approach for evolving proteins and peptides with new functions, but the properties of the molecules that can be evolved are limited by the chemical diversity encoded. Herein, we report a system for incorporating non-canonical amino acids (ncAAs) into proteins displayed on phage using the pyrrolysyl-tRNA synthetase/tRNA pair. We improve the efficiency of ncAA incorporation using an evolved orthogonal ribosome (riboQ1), and encode a cyclopropene-containing ncAA (CypK) at diverse sites on a displayed single-chain antibody variable fragment (ScFv), in response to amber and quadruplet codons. CypK and an alkyne-containing ncAA are incorporated at distinct sites, enabling the double labeling of ScFv with distinct probes, through mutually orthogonal reactions, in a one-pot procedure. These advances expand the number of functionalities that can be encoded on phage-displayed proteins and provide a foundation to further expand the scope of phage display applications.