Interstitial collagenase MMP-1 and EMMPRIN in cell lines and in clinical specimens of cervical squamous cell carcinoma.

BACKGROUND: The aim of this study was to elucidate the features of the expression of matrix metalloproteinases inducer-EMMPRIN (EMN) and matrix metalloproteinase 1 (MMP-1) in cell lines and in clinical samples of cervical squamous cell carcinoma (SCC). MATERIAL AND METHODS: The study was carried out using RT-PCR, densitometry and immunohistochemical studies (IHC) on commercial cell lines Siha, Caski, transformed with HPV16; HeLa, and C33A transformed with HPV18, line C33A without HPV, and in clinical samples of SCC and morphologically normal tissue adjacent to the tumor. RESULTS: The data obtained indicate that the expression of mRNA EMN and MMP-1 occurs in all cell lines at different levels. HPV type and number of genes copies had no effect on expression degree both EMN and MMP-1. Gene expression of EMN and MMP-1 has been investigated in tumor and normal tissues. MMP-1 expression in tumor tissue in SCC, as a rule, has been significantly increased (2-6 times) compared to normal tissue. It was found in 90% of tumor samples. It is known, that MMP-1 promotes the development of invasive and metastatic processes. EMN expression was lower in the tumor tissue than in normal tissue in most cases. An increase in EMN expression was noted only in some cases of SCC. CONCLUSION: The data obtained indicate that MMP-1 can serve as a marker of the invasive potential of SCC. EMN, apparently, is not a major factor responsible for MMP-1 expression in SCC. Data are important for understanding the process of tumor development and may have prognostic value for the patient.

N-domain of angiotensin-converting enzyme hydrolyzes human and rat amyloid-ß(1-16) peptides as arginine specific endopeptidase potentially enhancing risk of Alzheimer's disease.

Alzheimer's disease (AD) is a multifactorial neurodegenerative disorder. Amyloid-ß (Aß) aggregation is likely to be the major cause of AD. In contrast to humans and other mammals, that share the same Aß sequence, rats and mice are invulnerable to AD-like neurodegenerative pathologies, and Aß of these rodents (ratAß) has three amino acid substitutions in the metal-binding domain 1-16 (MBD). Angiotensin-converting enzyme (ACE) cleaves Aß-derived peptide substrates, however, there are contradictions concerning the localization of the cleavage sites within Aß and the roles of each of the two ACE catalytically active domains in the hydrolysis. In the current study by using mass spectrometry and molecular modelling we have tested a set of peptides corresponding to MBDs of Aß and ratAß to get insights on the interactions between ACE and these Aß species. It has been shown that the N-domain of ACE (N-ACE) acts as an arginine specific endopeptidase on the Aß and ratAß MBDs with C-amidated termini, thus assuming that full-length Aß and ratAß can be hydrolyzed by N-ACE in the same endopeptidase mode. Taken together with the recent data on the molecular mechanism of zinc-dependent oligomerization of Aß, our results suggest a modulating role of N-ACE in AD pathogenesis.

Computer-aided selection of potential antihypertensive compounds with dual mechanism of action.

The prediction of biological activity spectra for substances as an approach for searching compounds with complex mechanisms of action was studied. New compounds with dual mechanisms of antihypertensive action were found by this approach. Biological activity spectra for substances were predicted on the basis of their structural formulas by the computer program PASS. Thirty molecular mechanisms of action of compounds from the MDDR 99.2 database, which cause the antihypertensive effect and can be predicted by PASS, have been identified. The analysis of predictions for compounds with 15 dual antihypertensive mechanisms of action from the MDDR 99.2 database has confirmed high accuracy of prediction. This approach was applied to databases of commercially available compounds (AsInEx and ChemBridge) and allowed us to select four substances that are potential inhibitors of angiotensin converting enzyme (ACE) and of neutral endopeptidase (NEP). At a later time, all these compounds were found to be the inhibitors of both ACE and NEP. The most potent compounds had IC(50) of 10(-7)-10(-9) M for ACE and 10(-5) M for NEP. New combinations of dual mechanisms of action never before found for antihypertensive compounds were predicted.