TOKYO, May 22 (IFR) - Japanese government bond prices were slightly softer on Thursday as share markets rose, but remained in a familiar range, with immediate focus on a 400 billion yen sale of long-dated bonds.

The 10-year cash JGB yield rose 0.5 basis point to 0.595 percent while the 10-year JGB futures price dipped 0.04 point to 145.18. The Nikkei share average rose 1.6 percent.

The Ministry of Finance is holding a "liquidity enhancement auction", in which it will re-offer existing issues with five to 15 years to maturity. Market players expect decent demand at the auction.

(Reporting by Masatsugu Hisatsune; Editing by Jacqueline Wong)