PROS1 and head and neck cancer: The GroL2 of M. bovis BCG (also known as 60 kDa chaperonin 2, protein CPN60-2, 65 kDa antigen, heat shock protein 65, cell wall protein A and antigen A46) is a well-known human47 and veterinarian48 vaccine candidate against TB as well as against head and neck cancer,49 that has been widely studied as a DNA vaccine in mice.50 GroL2 has 100% identity to the well-known GroEL2 of M.tb, 94.83% identity with GroEL of M.leprae, 93.37% identity with GroEL of the saprophyte M. smegmatis and 47.16% identity with human heat shock proteins.