Mevastatin in colon cancer by spectroscopic and microscopic methods - Raman imaging and AFM studies

One of the most important areas of medical science is oncology, which is responsible for both the diagnostics and treatment of cancer diseases. Simultaneously one of the main challenges of oncology is the development of modern drugs effective in the fight against cancer. Statins are a group of biologically active compounds with the activity of 3-hydroxy-3-methyl glutaryl-CoA reductase inhibitors, an enzyme catalyzing the reduction of 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) to mevalonic acid. By acting on this enzyme, statins inhibit the endogenous cholesterol synthesis which in turn causes the reduction of its systemic concentrations. However, in vitro and in vivo studies confirm also the cytostatic and cytotoxic effects of statins against various types of cancer cells including colon cancer. In the presented studies the influence of mevastatin on cancerous colon cells CaCo-2 by Raman spectroscopy and imaging is discussed and compared with biochemistry characteristic for normal colon cells CCD-18Co. Based on vibrational features of colon cells: normal cells CCD-18Co, cancerous cells CaCo-2 and cancerous cells CaCo-2 treated by mevastatin in different concentrations and incubation times we have confirmed the influence of this statin on biochemistry composition of cancerous human colon cells. Moreover, the spectroscopic results for colon normal cells and cancerous cells based on data typical for nucleic acids, proteins, lipids have been compared. The cytotoxisity of mevastatin was determined by using XTT tests.

Is stallion epididymal fluid phosphoproteome affected by the equine reproductive season?

Phosphorylation and dephosphorylation of proteins are considered to be the most important processes in sperm maturation during epididymal transit. The main aim of this study was to isolate and identify phosphoproteins from the epididymal milieu obtained from reproductively mature stallions during and out of the breeding season. With the use of 1D-PAGE and nanoLC-MS/MS, we identified phosphoproteins that fulfil various functions: regulatory, transport, motility, ubiquitination, chaperone, antioxidant, apoptotic and enzymatic. Moreover, we characterized tyrosine, serine and threonine phosphorylation patterns, taking into consideration the seasonal and epididymal segment variables. The intensity of phosphorylation and profiles of phosphoproteins varied in subsequent regions of the epididymis. With the use of western and immunoblot tests, we demonstrated that fourteen proteins underwent phosphorylation both during and out of the breeding season. However, significant differences (p≤0.05) in the phosphorylation status were demonstrated in the case of 44 kDa (glutamine synthetase), 38 kDa (malate dehydrogenase), 34 kDa (clusterin/inorganic pyrophosphatase), 31 kDa (clusterin/ /ubiquitin thioesterase), 29 kDa (14-3-3 protein/purine nucleotide phosphorylase) for the season factor and 55 (Rab GDP dissociation inhibitor alpha) and 31 kDa ((clusterin/ubiquitin thioesterase) proteins for the segment factor. The occurrence of the other phosphoproteins was spontaneous among individuals and in both seasons.

Relation between nitric oxide (NO) level in semen and certain properties of boar spermatozoa stored at 17°C

The aim of this study was to measure the NO level in boar semen held in a liquid state and to determine its putative relation to spermatozoa motility, plasma membrane integrity, mitochondrial membrane potential and ATP content. Generally, the percentage of spermatozoa which generated nitric oxide gradually increased, while NO level in the surrounding medium declined during the liquid preservation. NO generation in semen preserved in BTS was higher as compared to those in Androhep®Plus. We demonstrated the positive correlation between the NO level in fresh spermatozoa and their quality. We also showed negative correlation between nitric oxide level in spermatozoa preserved in BTS and sperm cells motility as well as plasma membrane integrity. Results obtained in this study confirm that NO may affect sperm physiology in a dualistic manner.

P2-12-05: Correlation between Quantitative HER2 Protein Expression and Risk of Brain Metastases in HER2−Positive Advanced Breast Cancer Patients Receiving Trastuzumab-Containing Therapy

Background. Patients with HER2−positive breast cancer are at particularly high risk for brain metastases; however, the biological basis is not fully understood. Within HER2−positive breast cancer tumors, it is possible to resolve a ∼1.5-log range of HER2 protein expression using a novel quantitative HER2 assay (HERmark®). We investigated the correlation between quantitative HER2 protein expression in primary breast cancers and the time to brain metastases (TTBM) in HER2−positive advanced breast cancer patients treated with trastuzumab.

Methods. The study group included 142 consecutive patients who were administered trastuzumab-based therapy for HER2−positive metastatic breast cancer, defined as 3+ categorical staining by immunohistochemistry (IHC). HER-2/neu gene copy number was subsequently quantified as HER2/CEP17 ratio by central laboratory fluorescence in situ hybridization (FISH). HER2 protein was quantified as total HER2 protein expression (H2T) by the HERmark assay in formalin-fixed, paraffin-embedded primary tumor samples. HER2 variables were correlated with clinical features and TTBM measured from the initiation of trastuzumab-containing therapy.

Results. H2T level (continuous variable) was correlated with shorter TTBM (HR=2.3; p=0.013), whereas HER2 gene amplification by FISH (p=0.28) and continuous HER2/CEP17 ratio (p=0.25) had no significant prognostic impact. The correlation between continuous H2T level and TTBM was confirmed in a multivariate analysis (HR=3.2; p=0.021). Controlling for the competing risk of death from causes other than brain metastases, continuous H2T remained a strong correlate of TTBM (HR=2.7; p=0.0009). In the subset of patients that was centrally-determined HER2 positive by FISH (117 patients), above-median H2T level was significantly associated with shorter TTBM (HR=2.4; p=0.005), whereas this was not true for median FISH/CEP17 ratio (p=0.4). In a multivariate analysis of this subset, continuous H2T (p=0.021) and a time dependent covariate capturing time to non-brain metastases (p=0.0044) were prognostic for TTBM, whereas FISH/CEP17, ER, PgR and grade were not.

Conclusions. These data reveal a strong relationship between quantitative HER2 protein expression levels and the risk of brain relapse in HER2−positive advanced breast cancer patients. Consequently, quantitative assessment of HER2 protein expression may inform and facilitate refinements in therapeutic treatment strategies for selected subpopulations of patients in this group.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-12-05.

Extracellular superoxide dismutase of boar seminal plasma

Superoxide dismutase (SOD) is an enzymatic component of the antioxidant defense system that protects spermatozoa by catalysing the dismutation of superoxide anions to hydrogen peroxide and oxygen. Age and season effects on SOD activity in the seminal plasma were measured in boars at the onset of 8 months through a 35-month period. It was found that age-related changes in SOD activity in the seminal plasma were markedly higher in boars less than 2 years of age. However, it appeared that SOD activity was established at the early sexual maturity age (8-12 months). There were variations in SOD activity throughout the season, being significantly higher in spring and autumn than in summer. A secretory extracellular form of SOD (EC-SOD) was purified to homogeneity (350-fold) from boar seminal plasma, using a three-step purification protocol (affinity chromatography followed by ion exchange and ceramic hydroxyapatite chromatography). The molecular properties and specificity of SOD (molecular mass, isoelectric point, optimum pH, thermostability and susceptibility to inhibitors) confirmed that the purified enzyme is an extracellular form of Cu/Zn-superoxide dismutase occurring in boar seminal plasma. The results of this study indicate that EC-SOD is an important antioxidant enzyme of boar seminal plasma, which plays an important physiological role in counteracting oxidative stress in spermatozoa.

Isolation and biochemical characteristics of a molecular form of epididymal acid phosphatase of boar seminal plasma

The fluid of boar epididymis is characterized by a high activity of acid phosphatase (AcP), which occurs in three molecular forms. An efficient procedure was developed for the purification of a molecular form of epididymal acid phosphatase from boar seminal plasma. We focused on the epididymal molecular form, which displayed the highest electrophoretic mobility. The purification procedure (dialysis, ion exchange chromatography, affinity chromatography and hydroxyapatite chromatography) used in this study gave more than 7000-fold purification of the enzyme with a yield of 50%. The purified enzyme was homogeneous by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The purified molecular form of the enzyme is a thermostable 50kDa glycoprotein, with a pI value of 7.1 and was highly resistant to inhibitors of acid phosphatase when p-nitrophenyl phosphate was used as the substrate. Hydrolysis of p-nitrophenyl phosphate by the purified enzyme was maximally active at pH of 4.3; however, high catalytic activity of the enzyme was within the pH range of 3.5-7.0. Kinetic analysis revealed that the purified enzyme exhibited affinity for phosphotyrosine (K(m)=2.1x10(-3)M) and was inhibited, to some extent, by sodium orthovanadate, a phosphotyrosine phosphatase inhibitor. The N-terminal amino acid sequence of boar epididymal acid phosphatase is ELRFVTLVFR, which showed 90% homology with the sequence of human, mouse or rat prostatic acid phosphatase. The purification procedure described allows the identification of the specific biochemical properties of a molecular form of epididymal acid phosphatase, which plays an important role in the boar epididymis.

Loss of tumorigenicity of murine colon carcinoma MC38/0 cell line after transduction with a retroviral vector carrying murine IL-12 genes

Cells of transplantable MC38 colon carcinoma of C57BL/6 mice were adapted to growth in vitro as the MC38/0 cell line. Along the establishing process, MC38/0 cells preserved their tumorigenicity. After transduction with a retroviral vector carrying murine interleukin 12 (mIL-12) genes and further selection, stable MC38/IL-12 transductant cells were obtained. These cells produced IL-12 (approx. 2500 ng/ml/5x10(5) cells/48 h) as evaluated in the optimized bioassay. After subcutaneous inoculation into syngeneic mice, the IL-12-modified cells demonstrated reduced tumorigenicity as compared to parental MC38/0 cells. Mice that rejected the MC38/IL-12 tumour became protected against subsequent challenge with MC38/0 cells. The obtained data indicate that the IL-12-transduced murine colon carcinoma cells could be used both as a model tumour for the study of mechanisms of anticancer immunity and/or as an adjuvant to cancer vaccines.

Purification and characterization of a protein tyrosine acid phosphatase from boar seminal vesicle glands

A protein tyrosine phosphatase (PTPase) with acid phosphatase activity was purified (500-fold) from the fluid of boar seminal vesicles. Preparative purification was performed with a 3-step procedure, employing FPLC S-Sepharose Fast Flow, Mono Q and Superdex 75 column. Protein tyrosine acid phosphatase (PTAPase) was homogeneous by polyacrylamide gel electrophoresis (PAGE, SDS-PAGE). PTAPase is a glycoprotein which has a molecular weight of about 41-42 kDa. This enzyme was maximally active at pH 5.5, and its thermostability was less than 80 degrees C. The K(m) value for p-nitrophenylphosphate, a specific synthetic substrate, was 0.87 x 10(-3)M, however, higher substrate specificity was shown when phosphotyrosine (K(m)=0.37 x 10(-3)M) and protein fragments, such as gastrin (K(m)=0.0032 x 10(-3)M) and hirudin (K(m)=0.0075 x 10(-3)M), were used as substrates. Activity of PTAPase was inhibited by dephostatin, molybdate and orthovanadate by 100, 95 and 70%, respectively, when phosphotyrosine was used as the substrate. Immunofluorescence study has shown that the seminal vesicles are the only source of PTAPase in boar seminal plasma.

[Growth of enterococci in normal and iron saturated serum]

Among 20 strains of genus Enterococcus isolated from different sources 12 strains multiplied in iron unsupplemented normal human serum. The excess of iron did not increase the rate of multiplication. Three strains survived in serum and growth of five strains was inhibited. The siderophores production had no effect on the multiplication of enterococci in serum unsupplemented with iron.

[Susceptibility of staphylococci to natural and synthetic iron chelators]

A total of 237 strains of staphylococci belonging to 27 species were tested for susceptibility to natural and synthetic iron-chelators. Coagulase-negative staphylococci were much more susceptible than coagulase-positive ones: 82 out of 148 coagulase-negative strains were susceptible to desferrioxamine B, rhodotorulic acid and ovotransferrin and 7 out of 89 coagulase-positive strains. A correlation between the susceptibility to iron-chelators species affiliation and the origin of strain was not found.

Effect of depletion tests (DT) on the composition of boar semen

We conducted two depletion tests during the summer (DT 1) and winter (DT 2) to study their effect on selected biochemical parameters of boar semen. We subjected three boars to DT for 10 consecutive days. The first 3 days (Period 1) of ejaculate collections represented the reserves of the extragonadal spermatozoa and accessory sex gland secretions, whereas the other seven days (Period 2) represented the daily spermatozoa output and the secretory capacity of the accessory sex glands. We observed noticeable changes in the quantity and quality of the semen in DT 1 and 2. There was an increase in the number of spermatozoa with morphological defects, particularly coiled tails and detached acrosomes. The secretory activity of the accessory sex glands, particularly the vesicular glands, was slightly influenced by season. Depletion tests caused disturbances in the qualitative relations of secretions of the accessory sex glands, which were related to changes in the sperm plasmalemma integrity. These tests can be used to determine the total spermatozoa output, and to assess the secretory capacity of the accessory sex glands of boars.

[Hydroxamate siderophores in enterococci]

In 70 enterococcal strains of diverse origin belonging to 16 species a hydrooxamate class siderophore was detected with chemical and biological tests. A correlation between hydrooxamate siderophore production, species affilIation and pathogenicity of enterococci was not found.

Occurrence of siderophores in enterococci

In 70 strains of the genus Enterococcus belonging to 16 species and isolated from clinical material, animals and the environment, a hydroxamic class of siderophores was detected with the aid of chemical and biological tests. A correlation between siderophore activity and species affiliation was found: E. faecalis strains showed the highest siderophore activity. A correlation between siderophore activity and pathogenicity could not be confirmed.

Biochemical properties and usefulness of boar semen for liquid preservation following atropine administration

Four sexually mature boars were used in two different experiments. In Experiment I, two boars were injected once subcutaneously with atropine and, ejaculates were collected after 30, 60 and 90 min. In Experiment II, each boar was injected weekly with 25, 37.5 and 50 mg of atropine, and ejaculates were collected after 30 min. Ejaculates obtained in Exp. II were diluted with Kortowo-3 extender (Olsztyn, Poland), with and without the addition of low density lipoprotein fraction (LDF) isolated from hen egg yolk,and stored at 5 degrees C and 16 degrees C for 5-6 days. Atropine caused a decrease in semen volume and an increase in sperm concentration with fewer agglutinated spermatozoa. Changes in sperm motility were not significant. There was a significant increase in the content of fructose, zinc, citric acid and protein in the seminal plasma of atropine-injected boars. Furthermore, increased antiproteolytic and antiperoxidant activity as well as seminal phosphatases were also observed. No significant changes were observed in the content of free sialic acid, whereas bound sialic acid was significantly increased in Exp. II. A decrease in osmolality and pH of seminal plasma was observed. Electrophoretic studies revealed that there were alterations in the molecular forms of seminal phosphatases and proteinase inhibitors. There were no significant changes in the percentage of morphologically abnormal spermatozoa, osmotic plasmalemma resistance at the acrosomal region (ORT) and malondialdehyde production in the spermatozoa. AspAT activity recovered from cold shocked spermatozoa was significantly reduced, whereas disturbances in plasma membrane permeability to fluorochrome HO 258 were observed in Exp. I. Semen of atropine-injected boars had increased sperm viability during liquid preservation at 5 and 16 degrees C.

The change of therapy in esophagus carcinoma between 1975-1996

196 patients were assigned to an operation because of esophagus carcinoma between 20.05.1975 and 30.09.1996. Whereas until 1984 the surgical treatment was predominantly characterized by the uni-cavity operation, we increasingly practice the bi-cavity operation since them. By this procedure the resection rate could be extended up to 70.1%. As to be expected, most of the carcinomas were positioned in the medium third of the esophagus, the predominant tumor type was the squamos cell carcinoma, 85% of the patients had a stage three tumor. The mortality rate was 19.1% within the period of 6 weeks after the operation.

The oncological approach to pylorus preserving pancreatoduodenectomy (PPPD) in pancreas malignancies

There has been a considerable debate about whether pylorus preservation significantly detracts from the radicality in a palliative procedure where a conventional Whipple operation would have been curative. We know now, that the extending radicality of the Whipple operation does not improve the long-term survival rates. Our results of 127 PPPD and 54 Whipple procedures in pancreas malignancies from 1985 to 1996 showed the nutritional benefits of the PPPD group as compared to the standard Whipple group. 84% (99/121) vs. 24% (13/50) were able to gain postoperatively. The long-term survival rates of both groups and the results in the literature are similar.

[Usefulness of volumetric studies in the evaluation of respiratory efficiency in nervous system diseases]

In nervous system diseases impairing the efficiency of respiratory muscles the authors determined vital capacity, minute ventilation and respiratory capacity. On the basis of volumetric investigations the authors tried to find an optimal schedule for administration of drugs in myasthenia and determine the usefulness of volumetric and gasometric measurements for the evaluation of respiratory efficiency in neurological diseases.