TOKYO (Kyodo) -- Tokyo stocks ended mixed Thursday, with the Nikkei index giving up earlier gains, as investors became increasingly wary over the business outlook as the earnings season gets into full swing.

The 225-issue Nikkei Stock Average ended down 128.39 points, or 0.34 percent, from Wednesday at 38,073.98. The broader Topix index finished 7.03 points, or 0.26 percent, higher at 2,713.46.

On the top-tier Prime Market, gainers were led by insurance and bank issues, while nonferrous metal and electric appliance issues led decliners.

The U.S. dollar moved narrowly around the mid-155 yen zone in Tokyo, supported by the likelihood of a continued wide gap in U.S.-Japan interest rates, while there remained caution over a possible intervention by Japanese authorities to prop up the yen, dealers said.

Stocks opened higher after the Nikkei benchmark lost more than 600 points the previous day. But the market was top-heavy as investors awaited company earnings reports for the fiscal year ended March and their projections for the current business year.

Earnings projections "have been weaker than what investors had anticipated," said Makoto Sengoku, senior equity market analyst at the Tokai Tokyo Intelligence Laboratory Co.

"Investors were reluctant to actively engage in buying as a notable number of companies are reporting forecasts that fall below consensus," he said.

While the downside of stocks is expected to remain solid on dip-buying, the market lacks incentives to help the Nikkei recover the 40,000 threshold, Sengoku said.