Is Development of High-Grade Gliomas Sulfur-Dependent?

We characterized γ-cystathionase, rhodanese and 3-mercaptopyruvate sulfurtransferase activities in various regions of human brain (the cortex, thalamus, hypothalamus, hippocampus, cerebellum and subcortical nuclei) and human gliomas with II to IV grade of malignancy (according to the WHO classification). The human brain regions, as compared to human liver, showed low γ-cystathionase activity. The activity of rhodanese was also much lower and it did not vary significantly between the investigated brain regions. The activity of 3-mercaptopyruvate sulfurtransferase was the highest in the thalamus, hypothalamus and subcortical nuclei and essentially the same level of sulfane sulfur was found in all the investigated brain regions. The investigations demonstrated that the level of sulfane sulfur in gliomas with the highest grades was high in comparison to various human brain regions, and was correlated with a decreased activity of γ-cystathionase, 3-mercaptopyruvate sulfurtransferase and rhodanese. This can suggest sulfane sulfur accumulation and points to its importance for malignant cell proliferation and tumor growth. In gliomas with the highest grades of malignancy, despite decreased levels of total free cysteine and total free glutathione, a high ratio of GSH/GSSG was maintained, which is important for the process of malignant cells proliferation. A high level of sulfane sulfur and high GSH/GSSG ratio could result in the elevated hydrogen sulfide levels. Because of the disappearance of γ-cystathionase activity in high-grade gliomas, it seems to be possible that 3-mercaptopyruvate sulfurtransferase could participate in hydrogen sulfide production. The results confirm sulfur dependence of malignant brain tumors

The example of real time migration assay of stimulated and controlled HUVECs directly from the X-Celligence system.

<p>The assay was repeated seven times with similar result during 25h observation at 37^°C. The difference between migration curves for cells in cultures with presence of hAM CCM and in control medium was significant. (p < 0.05).</p

Effect of hAM CCM on HUVECs migration assayed by scratch test.

<p>There are results of 160 measurements, 8 independent assays with 10 measurements for test and control each. Median values and (P25, P75) are shown (n = 8, p < 0.05). Detailed description of the assay is in Material and methods.</p

Growth factors in hAM CCM.

<p>Forty-one growth factors were quantitated by antibody array and the obtained values were combined into following growth factor families: EGF family (EGF-2, HB-EGF, EGF-R); FGF family (bFGF, FGF-4, FGF-6, FGF-7); Hematopoietic factors HF (MCSF, MCSF-R, SCF, SCF-R); IGF family (IGF-1, IGF-2, IGF-1SR); IGFBP family (IGFBP-1, IGFBP-2, IGFBP-3, IGFBP-4, IGFBP-6); Neurotrophic factors NF (bNGF, GDNF, NT-3, NT-4); PDGF family (PDGF-AA, PDGF-AB, PDGF-BB, PDGF-Ra, PDGF-Rb); TGF family (TGF-α, TGF-β, TGF-β2, TGF-β3); Vasculogenic factors VF (PLGF, VEGF, VEGF-R3, VEGF-D, VEGF-R2); some growth factors are presented separately: AR; G-CSF; GM-CSF; HGF. Each growth factor fluorescence value (FV) was measured and calculated as described in Materials and methods. (n = 4) (p < 0.05).</p