European stocks opened higher on Wednesday, with mining companies leading the gains thanks to rising metal prices, while Swiss pharmaceutical company Roche boosted healthcare stocks. By 07:07 GMT, the pan-European Stoxx 600 index rose by 0.4 percent. Mining stocks increased by 0.9 percent as most industrial metal prices climbed. Roche's shares jumped by 3.1 percent after the Swiss drugmaker unintentionally released data from its clinical trials for a new lung cancer treatment. The broader healthcare sector index rose by 0.8 percent. Shares of Société Générale increased by two percent.