The HealthShares Emerging Cancer ( HHJ) exchange-traded fund was one of the best performers during Tuesday's abbreviated session, thanks to a nearly 10% surge in shares of Dendreon ( DNDN). Traders expect that Dendreon will announce positive news on its prostate cancer drug, sending the stock up 68 cents to $7.91. The HealthShares Emerging Cancer ETF was recently adding 30 cents, or 1.4%, to $21.90. The iShares Dow Jones U.S. Broker-Dealer ( IAI) was also gaining ground, thanks to holdings Morgan Stanley ( MS), Merrill Lynch ( MER), Goldman Sachs ( GS) and Bear Stearns ( BSC), all of which were higher by 1% or more. The Broker-Dealer ETF was recently up 66 cents, or 1.2%, to $55.93. Meanwhile, shares of Apple ( AAPL) jumped more than 4%, powering the Internet Architecture HOLDRs ( IAH) higher. Apple's new iPhone should deliver profit margins of 55% on the $600 eight gigabyte version, according to iSuppli. The ETF was rising by 49 cents, or 1%, to $48.18. On the other hand, bundled securities tracking silver and gold were among the worst performers. Silver futures fell by 4 cents to $12.64 an ounce. Gold futures was losing $4.20 to $655 an ounce The PowerShares DB Silver ( DBS) was down 24 cents, or 1%, to $24.69. The iShares Silver Trust ( SLV) was down 97 cents, or 0.8%, to $124.91. The PowerShares DB Gold ( DGL) eased 20 cents, or 0.8%, to $25.80. The PowerShares DB Precious Metals ( DBP) shed 17 cents, or 0.7%, to $25.54.