Chu is the pinyin romanization of several different Chinese family names, which including 楚 Chǔ, 储 Chǔ, 褚 Chǔ, 触 Chù, etc.
However, in the Wade-Giles romanization system, Chu stands for 朱 (Zhu in pinyin), also can refer to several Chinese family names. In Hong Kong, Macao, this is also the spelling for the surname 朱.
In Taiwan, the last name Chu can be referred to 朱(Zhu in pinyin), 曲(Qu in pinyin), 祝(Zhù in Pinyin), etc.
The name is transliterated as Sở in Vietnamese