The optimal model included genes such as GGTLC1, SLPI, SFTPB, CXCL17, POLR2F, KRT18, CHCHD2, and GPRC5A. Immunohistochemical data demonstrated elevated expression levels of CHCHD2 in lung cancer tissues compared to normal tissues [70, 71]. Here, POLR2F is linked to lung cancer.