# Thirty Years of Mentoring by “Bob Chan” of Young Japanese Surgeons to Become Scientists: An Adventure of Love

## TL;DR

A 30-year mentorship program helped Japanese surgeons become leading scientists by combining advanced cancer research tools with international collaboration.

## Contribution

A successful model for training surgeon-scientists through international collaboration and innovative translational research tools.

## Key findings

- FUCCI imaging revealed most solid cancer cells are non-cycling and resistant to conventional therapies.
- PDOX models and A1-R bacteria provided clinically relevant platforms for evaluating novel cancer treatments.
- Mentees now lead research labs in Japan, continuing global partnerships in precision cancer therapy.

## Abstract

Over the past three decades, we have mentored a generation of young Japanese surgeons, guiding them to become internationally recognized surgeon‐scientists. Through a unique collaboration between Japanese academic institutions and our laboratories at AntiCancer Inc. and the University of California, San Diego (UCSD), these trainees engaged in immersive translational research. They mastered advanced imaging and therapeutic tools including fluorescent‐protein technology, patient‐derived orthotopic xenograft (PDOX) models, the FUCCI cell‐cycle imaging system, tumor‐targeting
Salmonella typhimurium
A1‐R (A1‐R), and recombinant methioninase (rMETase) to treat the methionine addiction of cancer. These technologies enabled real‐time visualization of cancer biology in vivo, accurate modeling of tumor behavior, and the development of strategies to target quiescent, treatment‐resistant cancer cells. FUCCI imaging revealed that most solid cancer cells within tumors exist in non‐cycling states, which are largely unaffected by conventional therapies. Our team explored methods to decoy these cells into vulnerable phases of the cell cycle. PDOX models provided a clinically‐relevant platform to evaluate such strategies, while A1‐R and rMETase offered novel therapeutic avenues by exploiting cancer‐specific vulnerabilities. The present review highlights the scientific advances achieved through this collaboration, but also the human story of mentorship, cultural exchange, and the formation of a lasting international academic network and permanent friendship. Many of our mentees now lead research laboratories and academic departments across Japan, continuing the cycle of innovation and global partnership. We reflect on this journey as a successful model for training surgeon‐scientists and advancing precision cancer therapy through visualization, imagination, and mentorship.

This article reflects on a 30‐year collaboration between Bob Chan's laboratory in San Diego and Japanese surgical institutions, highlighting the mentorship of young surgeons who became surgeon‐scientists. Through the development of advanced models such as PDOX models, FUCCI cell‐cycle imaging, A1‐R bacteria, and rMETase, this partnership fostered both scientific innovation and the academic surgeon mindset. The narrative underscores the value of international exchange in revitalizing surgical research and inspiring future generations.