U.S. stock futures are pointing to a lower open Thursday as some investors expressed disappointment over a lackluster sales performance from retailers in July, with a fresh rise in the price of oil further weighing on sentiment. Dow futures were off 32 points at 10,676, Nasdaq 100 futures fell 7 points to 1,625.50 while S&P 500 futures slipped 4 points to 1,243.80. "The retailers are going to be dragging things down here on the open," according to Brian Williamson, vice-president of equity trading at Boston Company Asset Management. "The same-store sales numbers appear fairly weak at this point in the morning. Williamson said the uptick in the price of oil in morning trading would further undermine sentiment. On Wednesday, stocks ended mixed in choppy trading marked by a retreat in crude-oil prices, Adidas-Salomon's $3.8 billion acquisition of Reebok and disappointing earnings from media giant Time Warner Inc.