Extending gains for the fourth straight session, the BSE benchmark Sensex rose by another 53 points in early trade today on sustained buying by funds and retail investors.The 30-share barometer, which had gained nearly 300 points in the previous three sessions, up by 0.31 per cent, at 17,445. All sectoral indices, except capital goods, were trading in the positive zone with gains of up to 0.69 per cent. The wide-based National Stock Exchange index Nifty moved up by 15.90 points, or 0.30 per cent, to 5,315. In the Asian region, the Hong Kong's Hang Seng Index rose by 0.17 per cent, while Japan's Nikkei index shed 0.91 per cent in morning trade today. The US Dow Jones Industrial Average ended 0.63 per cent lower in yesterday's trade.