Tokyo stocks opened lower Thursday as sentiments of cashing in gains were boosted after overnight falls in U.S. shares and the yen's advance. At 9:15 a.m., the 225-issue Nikkei Stock Average declined 141. 02 points, or 0.91 percent, from Wednesday to 15,374.04. The broader Topix index of all First Section issues on the Tokyo Stock Exchange was down 7.06 points, or 0.56 percent, to 1, 243.39.