March 19 (Reuters) - Wall Street's main indexes opened lower on Thursday as crude prices soared on intensifying Middle East hostilities, reviving inflation worries that have prompted the Federal Reserve to take a more cautious stance on interest rate cuts.

The rate-sensitive small-caps Russell 2000 index dropped 10% from its all-time intraday high.

The Dow Jones Industrial Average fell 90.3 points, or 0.20%, at the open to 46,134.87. The S&P 500 fell 41.6 points, or 0.63%, at the open to 6,583.12​, while the Nasdaq Composite dropped 281.4 points, or 1.27%, to 21,871.037 at the opening bell.

(Reporting by Johann M Cherian in Bengaluru; Editing by Devika Syamnath)