PT - JOURNAL ARTICLE AU - HIDEHARU BESSHO AU - BERNICE WONG AU - DAN HUANG AU - EE YAN SIEW AU - DACHUAN HUANG AU - JING TAN AU - CHOON KIAT ONG AU - SOO YONG TAN AU - KAZUMASA MATSUMOTO AU - MASATSUGU IWAMURA AU - BIN TEAN TEH TI - Inhibition of Placental Growth Factor in Renal Cell Carcinoma DP - 2015 Jan 01 TA - Anticancer Research PG - 531--541 VI - 35 IP - 1 4099 - http://ar.iiarjournals.org/content/35/1/531.short 4100 - http://ar.iiarjournals.org/content/35/1/531.full SO - Anticancer Res2015 Jan 01; 35 AB - Background/Aim: Placental growth factor (PlGF) is up-regulated in major malignant diseases or following antiangiogenic therapy, although it is present in low levels under normal physiological conditions. TB403, a monoclonal antibody against PlGF, was investigated in clear cell renal cell carcinoma (ccRCC) xenografts since it has been proposed as a potential target in oncology. Materials and Methods: Human ccRCCs were implanted in athymic nude mice to evaluate the efficacy of TB403 and to excise xenograft tumors for molecular experiments. Results: TB403 did not significantly inhibit tumor growth in treatment-naïve or sunitinib-resistant ccRCC xenografts. Gene expression profiling resulted in over-expression of the C1orf38 gene, which induced immunoreactivity in macrophages. Angiogenesis PCR arrays showed that VEGFR-1 was not expressed in ccRCC xenografts. Conclusion: PlGF blockade did not have a broad antiangiogenic efficacy; however, it might be effective on-target in VEGFR1-expressing tumors. The inhibition of VEGF pathway may induce the activity of tumor-associated-macrophages for angiogenesis escape.