* Nikkei down 1.5 pct, Topix off 1.0 pct * Exporters, securities firms weaken * Correction may drag Nikkei under 10,500 points - trader By Ayai Tomisawa TOKYO, Jan 16 (Reuters) - Japan's Nikkei share average fell on Wednesday, set to snap a four-day winning streak as investors took profits on exporters from a pause in the yen's weakness, while financial stocks also lost ground. Exporters led the losses, with Toyota Motor Corp falling 1.6 percent, Canon Inc dropping 2.7 percent and Fanuc Corp shedding 2.7 percent. Securities firms, which have been beneficiaries of the strong market, also weakened. Nomura Holdings skidded 1.2 percent and Daiwa Securities Group slipped 2.1 percent. The Nikkei dropped 1.5 percent to 10,720.18. Traders said that a pause in the yen's weakness triggered selling in shares that had gained recently, which could drag the index below the 10,500-mark in coming days. "It's a correction. Some exporters' gains are legitimate, but others aren't, so I am selling exporters which have gained while their fundamentals are still poor such as Panasonic," said Makoto Kikuchi, the chief executive of Myojo Asset Management. "Investors may not sell sharply before the BOJ meeting, but if the outcome of the meeting disappoints the market in any way, the index may be dragged down to near 10,200." The Nikkei has rallied about 24 percent over the past two months, spurred by weakness in the yen after Japan's new leader Shinzo Abe called on the Bank of Japan to adopt aggressive policies to energise the ailing economy, including setting an annual inflation target of 2 percent. The central bank will hold its policy review on Jan. 21-22. Hiroichi Nishi, an assistant general manager of equity research at SMBC Nikko Securities, said yen weakness has already been priced in as a positive catalyst. "Unless the yen weakens further, people may not chase the market higher aggressively," he said. The dollar last traded at 88.33, pulling away from a 2-1/2-year high of 89.67 set on Monday. The broader Topix shed 1.0 percent to 896.83.