The fourth retreat of the SYSU-CUHK State Key Laboratory (SKL) of Oncology in South China was held in Foshan from 21 to 22 April. Over 200 researchers and students from Sun Yat-sen University (SYSU) and the Chinese University took part. Prof. Ling Wen-hua, director of the Office of International Collaboration & Exchange—Office for Hong Kong, Macau & Taiwan Affairs, SYSU; and Prof. Chan Tak-cheung Anthony, CUHK, delivered the opening addresses. Prof. Zeng Yixin, Prof. Kung Hsiangfu, Prof. Ma Jun, Prof. Chan Tak-cheung Anthony and Prof. To Ka-fai, co-chaired the meeting. Collaborative projects particularly in cancers common in southern China were discussed. Around 60 posters were presented and adjudicators from both universities awarded joint first prize to PhD student Fan Yichao and research associate Kang Wei, both from CUHK.