Open a profile view for the element in question. Then select the profile element and use the element information tool to list the elements the profile "DependsOn".
Multiple profiles can be assigned to horizontal geometry so just use the Profile By Slope From Element tool again to generate the desired profile and then set it active in the profile view. If the original profile is no longer needed then just delete it. I am not aware of any method to directly swap the parent element where the profile was projected from in the current version.