Reverse-QTY code design of active human serum albumin self-assembled amphiphilic nanoparticles for effective anti-tumor drug doxorubicin release in mice

Abstract

H uman s erum a lbumin (HSA) is a highly water-soluble protein with 67% alpha-helix content and three distinct domains (I, II, and III). HSA offers a great promise in drug delivery with enhanced permeability and retention effect. But it is hindered by protein denaturation during drug entrapment or conjugation that result in distinct cellular transport pathways and reduction of biological activities. Here we report using a protein design approach named r everse- QTY (rQTY) code to convert specific hydrophilic alpha-helices to hydrophobic to alpha-helices. The designed HSA undergo self-assembly of well-ordered nanoparticles with highly biological actives. The hydrophilic amino acids, asparagine (N), glutamine (Q), threonine (T), and tyrosine (Y) in the helical B-subdomains of HSA were systematically replaced by hydrophobic leucine (L), valine (V), and phenylalanine (F). HSA rQTY nanoparticles exhibited efficient cellular internalization through the cell membrane albumin binding protein GP60, or SPARC ( s ecreted p rotein, a cidic and r ich in c ysteine)-mediated pathways. The designed HSA rQTY variants displayed superior biological activities including: i) encapsulation of drug doxorubicin, ii) receptor-mediated cellular transport, iii) tumor cell targeting, and iv) antitumor efficiency compare to denatured HSA nanoparticles. HSA rQTY nanoparticles provided superior tumor targeting and antitumor therapeutic effects compared to the albumin nanoparticles fabricated by antisolvent precipitation method. We believe that the rQTY code is a robust platform for specific hydrophobic modification of functional hydrophilic proteins with clear-defined binding interfaces.

GP60 and SPARC as albumin receptors: key targeted sites for the delivery of antitumor drugs

“…We proposed a strategy to make albumin self-assemble into nanoparticles without the addition of organic reagents using the technology of reverse QTY code several months ago. The experimental results showed that albumin nanoparticles modified by the technology of reverse QTY code can maintain its biological activities and target tumor tissue or cells efficiently via the GP60 receptor and SPARC pathway ( Meng et al, 2023 ). Next, we will continue to conduct research to show better effects of tumor treatment in pigs, monkeys, and even human applications as well.…”

“…These data thus provided new scientific rationale for the development of a novel albumin drug delivery strategy via a denatured albumin receptor ( Hama et al, 2021 ). Our previous work showed that biologically active albumin nanoparticles can effectively target solid tumors via GP60 and SPARC pathways and can effectively inhibit tumor growth and prolong the survival time of tumor-bearing mice ( Meng et al, 2023 ). Albumin drug delivery systems constructed based on the GP60 or SPARC pathway are numerous.…”

PRO-LDM: Protein Sequence Generation with a Conditional Latent Diffusion Model

“…S17D-G). This diminished the purpose of generating proteins with higher fluorescence with the current dataset and was not further pursued, but may be relevant in other property-tuning tasks, such as designing lower-solubility proteins for selfassembly (56). Moreover, when 𝑤𝑤 reached values above 500, the generated sequences gradually lost their foldability and stability, resulting in a significant decline in pLDDT scores (fig.…”

Structural bioinformatics studies of glutamate transporters and their AlphaFold2 predicted water-soluble QTY variants and uncovering the natural mutations of L->Q, I->T, F->Y and Q->L, T->I and Y->F

“…Additionally, we developed a program and website for designing water-soluble QTY variants of membrane proteins [ 19 ]. The reverse QTY-code was recently described based on similar biochemical characteristics [ 20 ]. AlphaFold2 greatly accelerated research on predictions of protein structures with high accuracy, enabling the design of novel proteins, and the identification of new protein interactions and functions [ 21 ].…”