Preheat a grill or grill pan to high heat.
Grill the corn, turning occasionally, until browned in spots and the kernels are tender, 15 to 20 minutes.
Meanwhile, in a small bowl, mash together the mayo, sour cream, lime juice and chipotle chiles. Season with salt and pepper.
In a medium saucepan over medium-low heat, melt the butter. Add the panko and oregano and season with salt. Toast in the pan for a few minutes, tossing to combine.
Smear the chipotle mayo on the grilled corn and coat with the panko mixture. Garnish with the chopped cilantro.