CEACAM5 and squamous cell carcinoma: The conjugation of AlS4Pc to monoclonal antibodies (Mab) lead to an enhanced phototoxicity in different cell lines such as human colon carcinoma LoVo [92], modified human ovarian carcinoma cells SKOV3-CEA-1B9 (SKOV cells transfected with carcinoembryonic antigen (CEA) cDNA and expressing two target antigens CEA and ErbB2) [60], and various squamous carcinoma cells including UM-SCC-11B, UM-SCC-22A, UM-SCC-22B, A431, SCV-7 and OE [56,93].