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 (CSCO 0.44%) will report its fiscal second-quarter results, with growth expected to be sluggish due to macroeconomic uncertainty. Also on Wednesday, Twitter (TWTR) and Whole Foods Market (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.

The next billion-dollar iSecret
The world's biggest tech company forgot to show you something at its recent event, but a few Wall Street analysts and the Fool didn't miss a beat: There's a small company that's powering their brand-new gadgets and the coming revolution in technology. And we think its stock price has nearly unlimited room to run for early in-the-know investors! To be one of them, just click here.

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.