SINGAPORE, May 5 (Reuters) - Impact Therapeutics, a Chinese cancer-drug developer, aims to raise up to $117 million in a Hong Kong initial public offering, according to a term sheet seen by Reuters on Tuesday.

o Impact is offering 41.98 million shares at HK$19.75 to HK$21.75 ($2.52 to $2.78) each.

o The deal could rise to $134 million if underwriters use an over-allotment option.

o Six cornerstone investors, including Tencent, will buy about $35.7 million of the stock.

o Impact expects to price the IPO on May 11 and list on May 13.

($1 = 7.8329 Hong Kong dollars)

(Reporting by Yantoultra Ngui; Editing by Muralikumar Anantharaman)