Increased Circulating Level Of The Autocrine Growth Factor Gp88 (Pc Cell-Derived Growth Factor Factor/Progranulin) In Early- And Advanced-Stage Non-Small Cell Lung Cancer And Small Cell Lung Cancer

e18103 Background: GP88, is an 88 kDa glycoprotein autocrine growth factor belonging to a newly identified family of growth modulators characterized by unique cysteine-rich motif and playing a role in the proliferation and survival of human cancers by inhibiting apoptosis, stimulating cell migration and invasiveness, and promoting metastasis. In vitro and in vivo studies have examined the biological activity and expression of GP88 in human breast cancer. In particular, pathological and clinical studies investigating the expression of GP88 in lesions and sera from breast cancer patients demonstrated GP88 expression was associated with clinically poor prognosis. The current study evaluated GP88 in lung cancer. Methods: 28 patients newly diagnosed with SCLC or NSCLC or previously diagnosed lung cancer and undergoing chemotherapeutic regimen change were enrolled. 20 healthy adults with similar background, including history of smoking, were enrolled as control group. Venous blood was collected and serum GP88 was tested by human GP88 ELISA. Results: 28 patients enrolled. 6 SCLC (1 Limited stage SCLC, five extended stage SCLC). 22 NSCLC, stage IV: 16, stage III: 3 and stage I: 3. The mean serum GP88 level in the lung cancer study group was 46.5 ± 15.5 ng/mL while the mean serum GP88 level in the control group was 28.4 ± 5.6 ng/mL, p = 0.0004 (Wilcoxon rank sum test). Conclusions: In patients diagnosed with SCLC/NSCLC, there is a statistically significant increase of serum GP88. Further studies will be planned to explore the role of GP88 as a biomarker for diagnosis and prognosis of lung cancer. We are currently accruing additional pts and analyzing whether GP88 has prognostic or predictive value. No significant financial relationships to disclose.