Role of tumor/endothelial cell interactions in tumor growth and metastasis.

Background: It is known that interactions between tumor and endothelial cells have a significant influence on the growth and metastasis of malignant tumors.

Aim: To study the reciprocal effect of Lewis lung carcinoma (LLC) and endothelial cells on the growth rate of each other upon their co-cultivation in vitro and to assess the contribution of such tumor/endothelial cell crosstalk to in vivo LLC growth and metastasis.

Materials And Methods: Two variants of Lewis lung carcinoma cells, high-metastatic (LLC) and low-metastatic (LLC/R9), and murine aorta endothelial cell line (MAEC) were used.

Formation of multicellular aggregates under different conditions of microenvironment.

Multicellular aggregates (spheroids) represent an intermittent level between monolayer growing cells and tissue culture. Spheroids are rather objective model of the three-dimensional growth and organization, the cell-to-cell interactions and influence of microenvironmental conditions on tumour microaggregates. In our work formation and growth of spheroids depends on concentration of CMC and FCS.

Changes in VEGF level and tumor growth characteristics during lewis lung carcinoma progression towards cis-DDP resistance.

Aim: To study the relationship between tumor angiogenic potential and its growth and metastasis using Lewis lung carcinoma (LLC) models with different degree of resistance to cis-diamminedichloroplatinum (cis-DDP).

Methods: LLC and its two cis-DDP-resistant variants (LLC-9 LLC-19), were used. For determination of angiogenic potential of LLC, LLC-9 and LLC-19, the level of VEGF production by these tumor cells in vitro and the level of circulating VEGF during tumor growth in vivo was measured by enzyme-linked immunosorbent assay.

Influence of aconitine-containing herbal extract BC1 on proliferative and electrokinetic characteristics of endothelial cells.

Aim: To evaluate the influence of new antitumor preparation BC1 produced on the base of Aconitum species on viability and electrokinetic properties of endothelial cells for estimation of mechanisms of its antitumor and antimetastatic activity.

Materials And Methods: Cytotoxic/cytostatic action of BC1 toward murine aorta endothelial cells (MAEC) and tumor LLC/R9 cells was studied using MTT-test. Apoptotic rate of MAEC was performed by flow cytometry.

Epidermoid carcinoma-derived antimicrobial peptide (ECAP) inhibits phosphorylation by protein kinases in vitro.

Animal peptide antibiotics are thought to mediate their cytotoxic and growth inhibitory action on bacteria, fungi, and cancer cells through a membrane-targeted mechanism. Although the membrane interactions of the peptide antibiotics and their penetration through the membranes have been studied in several models, the precise chain of events leading to cell death or growth arrest is not established yet. In this study we used in vitro kinase assays followed by imaging analyses to examine the effect of human cationic antimicrobial peptide ECAP on the activity of the protein kinases.