Hundreds of companies are set to report their quarterly results next week, but there are a few that investors should keep an eye on. On Wednesday, networking giant Cisco Systems (NASDAQ:CSCO) will report its fiscal second-quarter results, with growth expected to be sluggish due to macroeconomic uncertainty. Also on Wednesday, Twitter (NYSE:TWTR) and Whole Foods Market (NASDAQ:WFM) will report their results. Both companies have seen their stock prices tumble over the past year as investors have reined in their expectations.

Click through the following slideshow for more details on these three stocks to watch.

Cisco is facing quite a few challenges, including the growing popularity of software-defined-networking and the shift to cloud computing. However, Cisco does enjoy some important competitive advantages, including meaningful switching costs. 2016 is unlikely to be a blowout year for Cisco, but the company should do just fine.

Twitter is facing a genuine crisis. I called Twitter stock a disaster waiting to happen last April, and the stock has fallen off a cliff since then. Here are a few things investors should pay attention to when Twitter reports its fourth-quarter results.

Whole Foods is facing increasing competition, both from natural grocers as well as traditional supermarket chains, and its results have suffered as a result. Whole Foods is certainly capable of turning things around, but there are a few risks that investors should know about. 

John Mackey, co-CEO of Whole Foods Market, is a member of The Motley Fool's board of directors. Timothy Green owns shares of Cisco Systems. The Motley Fool owns shares of and recommends Twitter and Whole Foods Market. The Motley Fool recommends Cisco Systems. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.