Share prices closed slightly lower amid concern about the yen's continuing strength against the US dollar, dealers said. The benchmark Nikkei 225 Stock Average closed 89.79 points or 0.5 pct lower at 16,862.14, after touching a low of 16,840.85. The TOPIX index of all first-section issues fell 13.75 points or 0.8 pct to 1,711.31, off a low of 1,708.99. Losers overwhelmed winners 1,218 to 377, with 98 issues unchanged. Volume fell to 1.75 bln shares from 2.07 bln shares yesterday. The dollar was changing hands at 111.21 yen at the close of stock trading here.