Dendreon (NASDAQ: DNDN ) added 14.71% to $5.85 in the pre-market session. Analysts at Bernstein upgraded Dendreon from “market perform” to “outperform.” Best Buy Co (NYSE: BBY ) surged 6.55% to $13.01 in the pre-market session. Best Buy reported a 1.4% drop in its same-store sales in the nine