Lung cancer and smoking in Finland and the Czech Republic. Recent trends and predictions.

Trends of mortality from lung cancer in 1953-1989, age-specific lung cancer death rates of five-year birth cohorts, and the cigarette consumption were compared in Finland and the Czech Republic. While the lung cancer mortality and the smoking habits were fairly similar in Finland and the Czech Republic in the 1950s and early 1960s, contrasting differences gradually developed over the subsequent three decades in favor of Finland. In the year 1989, the Czech lung cancer death rates were much higher than the Finnish rates: in males 75.

Dipeptidyl peptidase IV in the human lung and spinocellular lung cancer.

The isoelectric point and proportions of soluble and membrane bound dipeptidyl peptidase IV (DPP-IV) in human lung and spinocellular lung cancer tissue were tested. It was found that soluble DPP-IV is relatively less frequent in the cancer than in normal lung tissue. We demonstrated multiple molecular forms of DPP-IV in normal and cancer lung tissues, differing probably not only in the degree of sialylation.

Aminopeptidases and angiotensin I-converting enzyme activities in primary human lung tumors and lung parenchyma.

The activities of alanyl aminopeptidase (AAP), arginyl aminopeptidase (RAP), alpha-glutamyl aminopeptidase (EAP) and angiotensin I-converting enzyme (ACE) were investigated in primary human lung tumors of different histological types and in matched lung parenchyma. In contrast to the studied aminopeptidases whose activity differences between tumor and lung tissues were infrequently significant, the activity of ACE was decreased highly significantly in the majority of lung tumors.

Dipeptidyl peptidase IV, prolyl endopeptidase and cathepsin B activities in primary human lung tumors and lung parenchyma.

The activities of dipeptidyl peptidase IV (DPP-IV), prolyl endopeptidase (PE) and cathepsin B (CB) were investigated in primary human lung tumours and matched lung parenchyma, using continuous-rate fluorometric assays of the enzymes. Squamous-cell lung carcinomas showed significantly higher specific activities of all three enzymes studied. In lung adenocarcinomas only activities of PE and CB were increased significantly.

Lack of benefit from semi-annual screening for cancer of the lung: follow-up report of a randomized controlled trial on a population of high-risk males in Czechoslovakia.

Cigarette-smoking males (6,364), aged 40-64, were randomized into an intervention group which received 6-monthly screening by chest X-ray and sputum cytology, and a control group which received no asymptomatic investigation. After 3 years, both groups entered a follow-up period during which they received annual chest X-rays. Lung cancer cases detected by screening were identified at an earlier stage, more often resectable, and had a significantly better survival than "interval" cases diagnosed mainly because of symptoms.

Increased cathepsin B activity in human lung tumors.

The occurrence and levels of cathepsin B activity were investigated in primary human lung tumors and lung metastases of renal, colorectal and urinary bladder carcinomas as well as in the associated apparently normal lung parenchyma using a continuous rate enzyme assay with Ac-Leu-Arg-Arg-NHMec (7-(N-acetyl-L-leucyl-L-arginyl-L-arginylamido)-4-methylcoumarin) as the fluorogenic substrate. The inhibition studies of the enzymic hydrolysis of the substrate provided evidence for the catalytic action of the cysteine proteinase cathepsin B (CB) in the lung tumor tissues and the lung parenchyma under the assay conditions used. In the studied group of twenty-four patients with primary lung tumors of all major histological types, the level of CB activity in the tumor tissue was increased twofold and more over that in the associated lung parenchyma in 83% and 75% of cases, when expressed on the basis of wet tissue weight and tissue DNA, respectively.

Stimulating effect of blood serums from tumor-bearing rats on cholesteryl ester synthesis in normal rat liver cytosol in vitro.

Addition of diluted blood serum from tumor-bearing rats stimulated significantly the synthesis of cholesteryl esters from labeled cholesterol and endogenous fatty acids in the cytosol derived from normal rat liver. With both Zajdela and Walker transplantable tumors this effect was found to be associated with the most intensive period of tumor growth. During chemical carcinogenesis induced by a single subcutaneous administration of benzo(a)pyrene the stimulating effect of sera was found to precede several weeks the appearance of palpable tumors and persisted during the period of progressive tumor growth.

Survival and mortality in a randomized study of lung cancer detection.

In a randomized prospective study of lung cancer detection in a high-risk population of over 6000 heavy smokers semiannual screening by X-ray and sputum cytology was compared to screening at a 3-year interval. The comparison of Kaplan-Meier estimates of survival curves done without and with correcting for lead-time bias disclosed a rather important impact of lead-time bias on survival comparisons. On the contrary, controlling for possible length bias had no obvious effect on the shape of survival curves.

A kinetic fluorometric assay of dipeptidyl peptidase IV in viable human blood mononuclear cells.

A continuous-rate fluorometric assay of dipeptidyl peptidase IV (DP-IV) in viable human blood mononuclear cells using 7-(L-glycyl-L-prolylamido)-4-methylcoumarin as the substrate is described. The assay method is accurate, rapid, and highly sensitive for measuring the level of cell-surface bound DP-IV activity in suspension of blood mononuclear cells, as well as of other viable cells bearing this enzyme. We believe that the kinetic assay is suitable for studying the regulation of expression and the role of plasma membrane-bound DP-IV on the cellular level.

Micropreparative separation of transfer ribonucleic acids by high-performance liquid chromatography.

A method was developed for the micropreparative separation of individual species of tRNA using reversed-phase high-performance liquid chromatography on large pore spherical silica bonded with C3 alkyl chains. Columns were eluted with linear gradients of decreasing sodium chloride and increasing methanol concentrations. The decreasing salt gradient gradually abolished hydrophobic interactions and a significantly higher selectivity was thus obtained when compared with increasing gradients of salts usually employed in reversed-phase separations of tRNA.

The contribution of discrimination analysis to the diagnostic decision in patients with lung carcinoma.

A set of 620 patients was examined. Out of them, 245 suffered from lung carcinoma of different type and stage, 28 suffered from other malignant tumors, 37 were affected with benign tumors, and 166 were suffering from a nonmalignant respiratory disease (tuberculosis, nonspecific pneumonia, chronic bronchitis, abscesses, cysts, asthma, lung fibrosis, bronchiectasis and sarcoidosis). In addition to these patients, 144 blood donors were examined who represented the control group of healthy individuals.

Cathepsin B in human breast tumor tissue and cancer cells.

The cysteine proteinase cathepsin B (EC 3.4.22.