Serum cytokine levels as predictive biomarkers of benefit from ipilimumab in small cell lung cancer.

Background. Immunotherapy has shown efficacy in small cell lung cancer (SCLC), but only a subset of patients benefits. Surrogate biomarkers are urgently needed. Our aim was to evaluate serum Th1, Th2, and proinflammatory cytokines in two cohorts of SCLC patients before and during treatment with chemotherapy with or without ipilimumab and to correlate them with survival. Patients and methods. Two cohorts of SCLC patients were studied: patients treated with chemotherapy (n = 47), and patients treated with chemotherapy plus ipilimumab (n = 37). Baseline, on-treatment and after-treatment serum samples were evaluated for the presence of IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-8, IL-10, IFN-gamma, TNF-alpha, GM-CSF, and Mip-1alpha using a Luminex assay. Differential changes in cytokines between cohorts were analyzed. Associations between cytokine levels and their changes with overall survival were evaluated. Results. Patients treated with ipilimumab showed a global increase of all cytokines after treatment initiation. A high level of IL-8 at baseline was associated with worse prognosis regardless of treatment. Baseline increased IL-2 levels predicted sensitivity to ipilimumab, while high IL-6 and TNF-alpha predicted resistance. An on-treatment increase in IL-4 levels in patients treated with immune-chemotherapy was associated with a better overall survival. Conclusions. The addition of ipilimumab to standard chemotherapy in SCLC modulates the serum levels of cytokines. Baseline levels and their change over time relate to overall survival. Blood-based biomarkers are convenient for patients, and our results support prospective validation of cytokines as predictive biomarkers for ipilimumab in SCLC.

Angiopoietin-2 is a negative prognostic marker in small cell lung cancer.

BACKGROUND: Small cell lung cancer (SCLC) is a highly lethal disease due to its chemorefractory nature after initial treatment. Angiogenesis plays an important role in tumor growth, metastasis and chemoresistance. We hypothesized that angiogenesis could predict chemoresistance in SCLC patients and be potentially a therapeutic target in this disease. METHODS: Serum samples from forty-three SCLC patients were prospectively obtained at diagnosis, response evaluation and progression. Angiogenesis-related cytokines (Angiopoietin-2, VEGF-A, C and D) were simultaneously quantified by Luminex Technology. Clinical data were prospectively recorder. RESULTS: Significantly higher concentration of angiogenesis-related cytokines were found in SCLC patients at diagnosis compared to healthy volunteers. High baseline serum concentration of Angiopoietin-2 (sAngiopoietin-2) were associated with a worse overall survival (p=0.006) and remained independently associated with survival in the multivariate analysis (p=0.008). In addition, sAngiopoietin-2 significantly increased at progression when compared to baseline. CONCLUSION: These data provide novel evidence on a role of sAngiopoietin-2 in the adverse clinical behavior of SCLC and could be a potential therapeutic target in this disease.

High circulating hepatocyte growth factor levels associate with epithelial to mesenchymal transition and poor outcome in small cell lung cancer patients.

We have previously shown that Met activation through the hepatocyte growth factor (HGF) increases tumorogenesis, induces epithelial-to-mesenchymal transition (EMT) and chemoresistance in SCLC. We sought to evaluate circulating HGF levels in SCLC patients and assess correlation with outcome and EMT features in the tumor. Serum samples from patients with SCLC were prospectively obtained at diagnosis, response evaluation and progression. HGF serum (sHGF) was quantified by ELISA. EMT markers and p-Met/Met were assayed by immunohistochemistry in tumor samples. Clinical data were prospectively recorder. One-hundred twelve patients were included. High baseline levels of sHGF were associated with shorter overall survival (p=0.006) and remained independently associated with survival in the multivariate analysis (p=0.016). For stage IV patients, an increase of sHGF levels at response evaluation (p=0.042) and at progression (p=0.003) were associated with poor outcome. sHGF levels were associated (p<0.05) with a mesenchymal phenotype in the tumor. In conclusion, high sHGF at diagnosis and increases during the course of the disease predict for poor outcome in SCLC patients and associate with EMT in the tumor. These data provide novel evidence on a role of sHGF in the adverse clinical behavior of SCLC and supports testing Met inhibitors in patients with high sHGF.