# Protein Nanocarriers: Targeted Theranostics for Cancer Treatment and Imaging

## TL;DR

This review explores how protein nanocarriers can deliver cancer drugs and imaging agents together, improving treatment and tracking while reducing side effects.

## Contribution

The paper provides a comprehensive review of recent advances in targeted protein-based nanocarriers for cancer theranostics.

## Key findings

- Protein nanocarriers offer biocompatible and biodegradable platforms for targeted drug and imaging agent delivery.
- They utilize receptor-specific targeting mechanisms to selectively reach cancer cells.
- Recent preclinical studies show their potential for improving cancer diagnosis and therapy.

## Abstract

Cancer treatment and imaging are still limited since many drugs and imaging agents can neither effectively nor selectively reach tumour tissues. Therefore, new strategies are needed to improve drug and imaging agent delivery and reduce side effects. This review focuses on targeted protein-based nanocarriers as innovative devices for cancer diagnosis and therapy (theranostics), capable of delivering drug(s) and imaging agent(s) simultaneously. We discuss overexpressed protein receptors in cancer cells that differ from normal tissue expression and can be exploited for targeted delivery. This review summarises recent preclinical studies using protein nanocarriers as targeted theranostic platforms to improve cancer treatment, reduce side effects, and enable non-invasive tracking of treatment progress. Overall, protein nanocarriers represent promising devices that combine imaging modalities and targeting strategies for more effective cancer diagnosis and therapy in the future.

Protein-based nanocarriers have gained considerable attention for targeted cancer theranostic applications due to their inherent biocompatibility, biodegradability, and facile functionalisation. In addition, some of their properties, such as self-assembling nature, low immunogenicity (if species matched), molecular recognition ability, and lack of persistence due to degradation into proteinogenic amino acids, make them highly suitable for oncology-related applications. Each protein-based nanocarrier exhibits unique physicochemical and biological properties. In this review, we summarise recent advances in targeted protein-based nanocarriers, including albumin, lipoproteins, ferritin, viral protein capsids, fibrin type proteins and silk proteins, emphasising receptor-specific targeting mechanisms, the integration of various imaging modalities along with their advantages and limitations, and the importance of employing advanced preclinical models for translational theranostic applications. This review also discusses the most recent and significant studies in the field, providing useful insights into future directions of protein-based nanocarriers for cancer theranostics.