S. Barlati

Different stages of transformation of Rous virus-infected cells evidenced by methylene blue staining.

Foci of Rous cells produced by various Rous sarcoma virus (RSV) strains stain with methylene blue and can be distinguished from the background of unstained density-inhibited normal cells. RSV-infected

Role of Fibronectin Degradation Products on Cellular Transformation

Abstract Plasminolytic fragments of Fibronectin but not of Fibrinogen have a potent transformation enhancing activity and may act, in vivo , as “natural tumor promoters”.

Activation of DNA Polymerase of Murine Leukemia Virus by Rifamycin Derivatives

Some rifamycin derivatives are strong inhibitors of DNA polymerase of RNA tumor viruses. However, when this activity is assayed in intact virions, in the presence of limiting concentrations of detergent, some concentrations of these drugs stimulate enzyme activity. Activation of the polymerase was achieved even in the absence of detergent in the presence of appropriate concentrations of these antibiotics. This property seems to be restricted to rifamycin derivatives possessing bulky non-polar side chains which give the molecule a ‘detergent-like’ character. It is not clear whether this property is also responsible for inhibition of the viral polymerase.

216 MIR-100 IS DOWNREGULATED FROM EARLY STAGES OF HEPATOCARCINOGENESIS AND CORRELATES WITH OVEREXPRESSION OF ITS TARGET PLK1

available kits. DNA samples were typed for SNPs: −1195 G>A of COX-2, −308 G>A of TNF-a, +936 C>T of VEGF-A and −174 G>C of IL-6 genes. RFLP-PCR method was used to type the SNPs. sIL-6 were dosed with a commercially available ELISA kit. Results: Our data show a statistically significant difference only for the SNP of VEGF-A +936 C>T between HCC and LC patients (P = 0.039). sIL-6 were higher in G/G compared to C/C genotypes in HCC (z = 2; P = 0.04) and G/G vs G/C (z = 1.8; P < 0.03). sIL-6 in G carriers (G/G+G/C) were higher in HCC 4.8 (0.2–17.5) vs LC patients 2.2 (0.07–11.5) (z = 2.8; P = 0.004). sIL-6 in HCC correlated with G carriers (G/G+G/C) (r = 0.25, P = 0.05). A positive correlation was found between sIL-6 levels and some liver function tests both in LC and in HCC. Conclusions: Our results show that C allele carriers in VEGF-A gene are more frequent in HCC vs LC, and confirm the association between the G carriers in IL-6 gene and higher sIL-6, suggesting that these genetic factors could contribute to the development of HCC.

Transformation-Enhancing Activity Present in the Plasma of Cancer Patients Binds to Gelatin

Abstract Transformation-enhancing activity (TEF activity) present in the plasma cryopre-cipitates (cryo) of cancer patients binds to gelatin. The gelatin-binding (GB) fraction from TEF positive plasma cryos contains high levels of high molecular weight fibronectin (FN) fragments, almost absent in the gelatin-nonbinding (GNB) fraction. A higher concentration of tissue-plasminogen activator (t-PA) is also present in the GB as compared to the GNB fraction.