Comment # 5 on bug 1188862 from Dr. Werner Fink

From mc(1) manual page

       If the program is compiled with the Slang screen manager instead of
       ncurses, it will also check the variable COLORTERM,  if
       it is set, it has the same effect as the -c flag.

Don't know why but our mc is using slang instead of ncurses

  ldd /usr/bin/mc | grep slang
          libslang.so.2 => /usr/lib64/libslang.so.2 (0x00007f086fe73000)