After yesterday's surprise comments from Fed Chair Janet Yellen regarding the potential for interest rate hikes by next year, many investors weren't sure how stocks would react the morning after. But encouraging economic news from a rise in the Leading Economic Index pointed to a rebound in growth later this year, and stocks responded favorably. Some of the best performers on Thursday included Synta Pharmaceuticals (NASDAQ: SNTA), Herman Miller (MLKN 1.71%), and Tower Semiconductor (TSEM 3.07%).

Synta jumped 9.5% as the small drugmaker released encouraging study results for its ganetespib treatment for metastatic breast cancer. The good news came on the heels of last week's announcement that ganetespib had been chosen to take part in a breast-cancer trial sponsored by a third-party investigator. The drug has the potential to fight a number of different types of cancer, including ovarian and non-small-cell lung cancer, as well as multiple myeloma. With promising study results, investors will get more excited about Synta's prospects to play a key role in treating cancer patients.

Herman Miller climbed more than 9% after reporting strong earnings last night. Revenue for the maker of office furniture and accessories climbed almost 8% year over year, but the more encouraging news came from a 21% jump in order growth, which stretched across its various business lines and geographical areas it serves. Although some of the growth that Herman Miller saw came from its acquisition of Maharam, which bolstered its Specialty and Consumer segment's results, CEO Brian Walker also highlighted gains in order growth from the U.S. government and key international markets. If economic conditions do, in fact, improve, Herman Miller is in a great position to capitalize.

Tower Semiconductor gained just less than 9% as the tech company said this morning that it had come to an agreement with its bondholders to improve the strength of its finances. Although the corporate structure of Tower's various subsidiaries is complex, the essence of the deal is that various Tower entities will issue new convertible bonds due in late 2018 to refinance bonds due next year. The move will reduce net debt by $55 million and extend its overall maturity, ensuring that Tower will have the financing it needs to support its growth initiatives well into the future.