Figure 2. FAVL is expressed at a high level in half of the tested carcinoma tissue samples and cancer cell lines.

(A) FAVL expression is elevated in 50% of lung cancer cell lines tested. Using specific FAVL antibody (Supplemental Figure 1), levels of FAVL protein were found to be higher in 8 out of 16 cancer cell lines tested (arrowheads) compared with 2 normal cell lines (the other normal cell line shown in Supplemental Figure 2A). TaqMan assay was used to confirm FAVL mRNA elevation in lung cancer cell lines carrying elevated FAVL protein levels. The VIC-FAVL splice junction (26mer, synthesized from ABI) was used as TaqMan probe, and 6FAM-actin (purchased from ABI) served as an internal control. Levels of FAVL mRNA are higher in lung cancer cells compared with normal lung cells (Beas2B) (relative expression ratio average ± SEM, with n = 3). (B) FAVL elevation also was found in nearly half of carcinoma tissue samples tested. Using IHC, FAVL shows focal or/and diffuse cytoplasmic staining on 13 out of 25 slides from lung cancer tissue, 30 out of 45 slides from prostate cancer tissue, and 10 out of 10 slides from osteosarcomas. But FAVL staining was negative in all normal samples tested (5 samples from lung tissue and 5 samples from prostate tissue) and in all normal tissue fields integrated in those malignant tissues, further indicating the specificity of FAVL expression in carcinoma cells (Supplemental Figure 2B). Images shown represent FAVL protein expression in lung cancer, prostate cancer, and osteosarcoma. NT, normal tissue.