Histological expression of angiogenic factors: VEGF, PDGFRalpha, and HIF-1alpha in Hodgkin lymphoma

Angiogenesis is a prerequisite for solid tumor growth, but there is relatively limited data regarding Hodgkin lymphoma. The purpose of this study was to examine the immunohistochemical expression of angiogenic and proliferation markers in Hodgkin biopsies in relation to clinical parameters. Immunostaining was performed on 65 Hodgkin biopsies with vascular endothelial growth factor (VEGF), hypoxia inducible factor-1 alpha (HIF-1alpha), platelet-derived growth factor receptor alpha (PDGFRalpha), Ki-67, and p53. Microvessel density (MVD) was determined by CD31 staining. In all cases, neoplastic cells and reactive background cells were evaluated. The neoplastic population expressed VEGF in 48% of the cases, HIF-1alpha in 54% of the cases, and PDGFRalpha in 95% of the cases. Both Ki-67 and p53 were positive in neoplastic cells in over 60% of the cases. The MVD had a median of 2.6/0.0625mm(2) which was not different from normal lymph nodes. VEGF in the non-neoplastic compartment showed increased staining in Ann Arbor stage I-II versus III-IV. In conclusion, VEGF, HIF-1alpha, and predominantly PDGFRalpha are expressed in neoplastic cells in the majority of Hodgkin lymphomas. As microvessel formation is not increased in Hodgkin, additional functions of these angiogenic molecules should be investigated.     

Advanced stoichiometric analysis of metabolic networks of mammalian systems

Metabolic engineering tools have been widely applied to living organisms to gain a comprehensive understanding about cellular networks and to improve cellular properties. Metabolic flux analysis (MFA), flux balance analysis (FBA), and metabolic pathway analysis (MPA) are among the most popular tools in stoichiometric network analysis. Although application of these tools into well-known microbial systems is extensive in the literature, various barriers prevent them from being utilized in mammalian cells. Limited experimental data, complex regulatory mechanisms, and the requirement of more complex nutrient media are some major obstacles in mammalian cell systems. However, mammalian cells have been used to produce therapeutic proteins, to characterize disease states or related abnormal metabolic conditions, and to analyze the toxicological effects of some medicinally important drugs. Therefore, there is a growing need for extending metabolic engineering principles to mammalian cells in order to understand their underlying metabolic functions. In this review article, advanced metabolic engineering tools developed for stoichiometric analysis including MFA, FBA, and MPA are described. Applications of these tools in mammalian cells are discussed in detail, and the challenges and opportunities are highlighted.     

Multiplexed analysis of angiogenesis and lymphangiogenesis factors predicts outcome for non-small cell lung cancer patients

Angiogenesis and lymphangiogenesis are key components of non-small cell lung cancer (NSCLC) tumor growth and metastatic spread; however, the prognostic and predictive role of angiogenic and lymphangiogenic biomarkers remains controversial for NSCLC patients. We assessed VEGF, VEGFC, VEGFD, VEGFR3 protein expression, tumor microvessel, and lymphatic vessel (LmVD) density by immunohistochemistry in 103 NSCLC; biomarkers were analyzed individually as well as multiplexed with each other. No correlations were identified between VEGF, VEGFC, VEGFD, or LmVD and clinical characteristics. VEGFR3 was correlated with VEGFC (p = 0.03), VEGFD (p < 0.0001), and intratumor LmVD (p = 0.03). Tumors that did not express VEGFR3 had a worse prognosis (log rank p = 0.03). VEGF was significantly correlated with survival in adenocarcinomas (log rank p = 0.014) but not in squamous cell carcinomas (log rank p = 0.5). Multivariate Cox regression analysis confirmed the independent prognostic potential of VEGFR3 (hazard ratio (HR) = 0.05; 95% confidence intervals (CI) = 0.008–0.32, p = 0.002) for all patients and VEGF (HR = 8.69, 95% CI = 1.4–53.69, p = 0.02) for adenocarcinomas. When biomarkers were multiplexed, only stage and VEGFC expression were independent predictors of survival for all patients. Weighted expression of VEGFC, VEGFR3, and stage was used to build a prognostic classifier for stage I–IIIA patients; patients in the low risk group had prolonged survival compared with high risk patients (log rank p = 0.02). There was no association between biomarkers and early recurrence or response to treatment. Angiogenic and lymphangiogenic biomarkers studied define subgroups of patients at high risk and may be useful for prognostic stratification of NSCLC patients especially those with early stage disease.