Differential inhibition of single and cluster type tumor cell migration.

For the control of tumor metastasis it is important to identify chemical compounds with antimigratory potency. Agents acting against single cell and cluster type migration are necessary for successful antimetastatic therapy. In the present study, the migration of HT-1080 fibrosarcoma cells and OSCORT osteosarcoma cells was compared in a Boyden chamber and in an extracellular matrix (ECM)-based three-dimensional cell culture (3-DCC) model system.

[Study of drugs against neoplastic metastasis].

Further progress in the therapy of malignant diseases is expected from the introduction of potent antimetastatic drugs. Surveying of the complex and multi-step behavior of the metastatic process, compounds showing inhibitory action against tumor cell migration may be ranked among the promising antimetastatic agents. Our present study indicate, however, that the antimigratory actions of certain antitumor drugs (doxorubicin, taxol), and inhibitors of signal transduction (PD-98059, LY-294002, SB-203580) are highly dependent on the assay applied (Boyden-chamber, 3D ECM cell culture).

The site-dependent growth characteristics of a human xenotransplanted basaloid squamous cell carcinoma.

Purpose: To improve our understanding of the aggressive behaviour of basaloid squamous cell carcinoma (BSCC) certain biological features related to malignancy were compared in the basaloid and in the squamous cell population of this tumour.

Methods: Growth rate, cell population kinetics parameters, ploidy and collagenase activity were measured in BSCC xeno-transplanted subcutaneously or into oral submucosa.

Results: The basaloid component of BSCC showed a growth advantage in the subcutaneous location and formed a mainly aneuploid population (69.

The pathomorphology of a human xenotransplanted basaloid squamous cell carcinoma.

To elucidate some factors related to the malignant phenotype of an oral tumor with mixed cell population the question has been raised whether the biological behavior of the basaloid or the squamous cells show any difference in an immunosuppressed host organism. Basaloid squamous cell carcinoma (BSCC) surgically removed from sublingual location was xenotransplanted either subcutaneously or in the oral submucosa and the histology, ultrastructures, LDH isoenzyme pattern were investigated. The epithelial origin of the established tumor line (HTB-1) could be recognized according to the characteristic epithelial ultrastructures, while the type of the LDH isoenzymes proved its human origin.

Establishment and characterization of a new transplantable pancreatic cancer xenograft (PZX-5) in immunosuppressed mice.

Conclusion: A new, stable, transplantable human pancreatic cancer xenograft (PZX-5) model has been established in CBA immunosuppressed mice.

Background: Numerous human pancreatic carcinomas have been successfully transplanted into athymic nude mice. However, artificially immunosuppressed animals have rarely been used as recipients.

The antiproliferative action of a melphalan hexapeptide with collagenase-cleavable site.

Purpose: The objective of the present study was to examine the relevance of collagenase in the antitumor action of a melphalan peptide (MHP) with a collagenase-cleavable sequence. The question was addressed as to whether collagenase may act as an activator or a target in the antiproliferative mechanism of MHP.

Methods: Melphalan was inserted into peptides representing the sequence Pro-Gln-Gly-Ile-Ala.

[Additional roentgen-anatomical examination of OP (orthopantomography) pictures].

The authors examined various anatomical details which appeared in the OP pictures with varying frequency and in various recognisable forms. They sought to help to a more perfect implementation and evaluation of techniques which are considered to be relatively new in our country.