Differential expression of c-Met in Kaposi's sarcoma according to progression stage and HIV infection status

Plasma biomarkers of clinical response during chemotherapy plus combination antiretroviral therapy (cART) in HIV+ patients with advanced Kaposi sarcoma

This study aimed to evaluate plasma concentration of selected cancer-associated inflammatory and immune-modulated cytokines in HIV+ patients with advanced Kaposi sarcoma (KS), and to explore candidate biomarkers capable of predicting clinical outcome in response to chemotherapy (CT) plus combination antiretroviral therapy (cART).

Thirty-seven plasma cytokines/chemokines were assessed by Luminex technology in 27 consecutive HIV+ KS patients, followed-up during CT and cART of maintanence (m-cART). Associations between plasma concentration of biomarkers and patient clinical response to m-cART were evaluated by means of Hazard Ratios (HRs) and corresponding 95% Confidence Intervals (CIs).

Plasma baseline concentration of Granulocyte colony-stimulating factor (G-CSF), Hepatocyte growth factor (HGF) and endoglin were found to be associated with m-cART clinical response (HR:1.56, 95%CI:1.09–2.22, p = 0.01; HR:0.32, 95% CI:0.10–0.99, p = 0.05; HR:0.72, 95% CI:0.54–0.96, p = 0.03, respectively). The multivariate analysis confirmed the associations of baseline plasma G-CSF and HGF concentration with m-cART clinical complete remission response (HR:1.78, 95% CI:1.15–2.74, p = 0.009; HR:0.19, 95% CI:0.04–0.95, p = 0.04).

Our exploratory study suggested that plasma G-CSF, HGF and endoglin may be novel predictors of clinical response during m-cART in HIV+ KS patients. Nonetheless, these findings should be further validated in an independent population study.

Coexpression of hepatocyte growth factor and its receptor c-Met correlates with high MIB-1 proliferative index in malignant fibrous histiocytoma

Hepatocyte growth factor (HGF) is a multifunctional cytokine that variably affects cell motility, proliferation, and morphogenesis. Little information is currently available on the HGF and its receptor c-Met expression in malignant fibrous histiocytoma (MFH). We immunohistochemically investigated the HGF and c-Met expression in 43 MFH tissue specimens. Furthermore, the correlation of the HGF and c-Met expression with tumor proliferative activity assessed by MIB-1 indices was analyzed. Our results showed that positive cytoplasmic immunoreactivity for HGF and c-Met was identified in tumor cells in 36 (84%) and 20 (47%) of the 43 MFH cases analyzed, respectively. Coexpression of HGF and c-Met was observed in 20 (47%) of the 43 MFHs, and was correlated with high MIB-1 proliferative indices (p = 0.0446). These findings strongly indicate that the HGF/c-Met signaling system plays an important role in promoting cell proliferation of human MFHs via an autocrine loop.