Heat oil in a large nonstick skillet over medium-high heat; cook cumin seeds for 30 seconds or until toasted, stirring frequently. Add the corn, onion, and garlic; sauté 5 minutes or until lightly browned. Add the zucchini, yellow squash, salt, and chiles, and sauté 6 minutes or until tender. Stir in cilantro. Remove from heat; sprinkle with cheese. Cover and let stand 5 minutes or until cheese melts.