Tokyo stocks opened lower Friday after overnight losses on Wall Street, with investors remaining wary due to the prospect of further aggressive interest rate hikes by the U.S. Federal Reserve. In the first 15 minutes of trading, the 225-issue Nikkei Stock Average fell 293.80 points, or 1.05 percent, from Thursday to 27,582.11. The broader Topix index was down 10.84 points, or 0.56 percent, at 1,939.59. On the top-tier Prime Market, decliners were led by marine transportation, mining, and electric appliance issues. At 9 a.m., the dollar fetched 143.33-34 yen compared with 143.44-54 yen in New Y…