(Updates at 0600 GMT)

TOKYO, July 26 (Reuters) - Japan's Nikkei share average

closed lower on Friday, reversing early gains and extending its

losing streak to an eighth session, as investors adjusted

positions amid uncertainties about Wall Street following a

fickle session.

The Nikkei fell 0.53% to close at 37,667.41, its

lowest close since April 25, after rising as much as 0.6% as

investors scooped up stocks that appeared undervalued.

For the week, it fell 5.48%, marking its worst week since

mid-April.

The broader Topix fell 0.38% to 2,699.54 and lost

5.28% for the week.

"There were no particular negative cues for the market, but

investors sold stocks to adjust positions ahead of the weekend,

as the U.S. market has been volatile and there could be a big

decline overnight," said Shoichi Arisawa, general manager of the

investment research department at IwaiCosmo Securities.

The S&P 500 and Nasdaq Composite ended a fickle session

weaker on Thursday, failing to regain lost ground as investors

grappled with the likely direction of megacaps.

The market was also cautious about the Bank of Japan's

policy decision due next week amid growing expectations that the

central bank could raise its policy rate, Arisawa said.

Heavyweight chip-related stocks fell, with Tokyo Electron ( TOELF )

falling 4.77% to drag the Nikkei the most. Advantest ( ADTTF )

lost 3.56%.

Renesas Electronics ( RNECF ) fell 5.48% to become the

biggest percentage loser on the Nikkei, extending declines after

the chipmaker reported a 29% fall in net profit for six months

to June on Thursday.

The bright side was that the market bought companies that

reported a positive outlook, said Shuutarou Yasuda, a market

analyst at Tokai Tokyo Intelligence Laboratory.

Hino Motors ( HINOF ) surged 12.76% to become the top

percentage gainer on the Nikkei after the truck maker narrowed

its quarterly net loss.

"With the earnings season continuing after next week, a

strong corporate outlook is expected to support the Nikkei,"

Yasuda said.

(Reporting by Junko Fujita; Editing by Christian Schmollinger

and Varun H K)