%hash1 = ("John", 43, "Paul", 25, "Marie", 22);
%hash2 = ("john", 43, "Paul", 25, "marie", 22); 
while (($KEY_2, $VALUE_2) = each %hash2){
    my @matches = grep { m/$KEY_2/i } keys %hash1;
    if (@matches) {
         print "$KEY_2 : Matched ", join(", ", @matches), "\n";
    }
    else{
         print "$KEY_2 : Did not match\n";
    }
}