Comparison of serum and bronchoalveolar lavage fluid sialic acid levels between malignant and benign lung diseases

BACKGROUND: It is known that tissue and serum sialic acid levels may be altered by malignant transformation. In this study, sialic acid levels were determined in bronchoalveolar lavage fluid (BAL) and serum in two groups of patients with lung cancer and non-malignant diseases of the lung. METHODS: Colorimetric methods were used for determination sialic acid in serum and in BAL samples. Flexible bronchoscopy was used to obtain the latter. RESULTS: Sialic acid levels in bronchoalveolar lavage fluid and serum did not show any statistically significant difference between subjects with malignant and the non-malignant lung diseases (p > 0.05). Sialic acid levels were also unrelated to the stage and localization of the tumor (p > 0.05). CONCLUSIONS: Sialic acid levels do not appear to be a good marker for discriminating malignant from non-malignant diseases of the lung

CK2 Enzyme Affinity Against c-myc(424-434) Substrate in Human Lung Cancer Tissue

CK2 is a serine threonine kinase that participates in a variety of cellular processes with more than 300 defined substrates. This critical enzyme is known to be upregulated in cancers, but the role of this upregulation in carcinogenesis is not yet fully understood but c-myc, one of the defined CK2 substrates, is a well-known proto-oncogene that is normally essential in developmental process but is also involved in tumor development. We evaluated the optimal enzyme and substrate concentrations for CK2 activity in both neoplastic and non-neoplastic human lung tissues using the c-myc(424-434) peptide (EQKLISEEDL) as a substrate. The activities measured for the neoplastic tissue were 600-750 U/mg protein while those for the control tissue was in the range of 650-800 U/mg. K-m value for c-myc peptide was determined as 0.33 mu M in non-neoplastic tissue and 0.18 mu M in neoplastic tissue. In this study, we did not observe an increased activity in the neoplastic tissue when compared with the non-neoplastic lung tissue, but we recorded two times higher affinity for c-myc(424-434) in cancer tissue. Considering the metabolic position of c-myc(424-434), our results suggest that phosphorylation by CK2 may be important in dimerization and thus it might affect the regulation of c-myc in cancer tissues

CK2 Enzyme Affinity Against c-myc 424-434

CK2 is a serine threonine kinase that participates in a variety of cellular processes with more than 300 defined substrates. This critical enzyme is known to be upregulated in cancers, but the role of this upregulation in carcinogenesis is not yet fully understood but c-myc, one of the defined CK2 substrates, is a well-known proto-oncogene that is normally essential in developmental process but is also involved in tumor development. We evaluated the optimal enzyme and substrate concentrations for CK2 activity in both neoplastic and non-neoplastic human lung tissues using the c-myc(424-434) peptide (EQKLISEEDL) as a substrate. The activities measured for the neoplastic tissue were 600-750 U/mg protein while those for the control tissue was in the range of 650-800 U/mg. K-m value for c-myc peptide was determined as 0.33 mu M in non-neoplastic tissue and 0.18 mu M in neoplastic tissue. In this study, we did not observe an increased activity in the neoplastic tissue when compared with the non-neoplastic lung tissue, but we recorded two times higher affinity for c-myc(424-434) in cancer tissue. Considering the metabolic position of c-myc(424-434), our results suggest that phosphorylation by CK2 may be important in dimerization and thus it might affect the regulation of c-myc in cancer tissues

Association of CTLA4 and CD28 Gene Variants and Circulating Levels of Their Proteins in Patients with Breast Cancer

Background/Aim: Breast cancer is one of the most common and lethal types of cancer among women. We focused on the importance of the immune system in the etiology of breast cancer by investigating critical polymorphisms of cytotoxic T-lymphocyte-associated protein 4 (CTLA4) and cluster of differentiation 28 (CD28) gene, and circulating levels of these proteins. Materials and Methods: A total of 79 patients with breast cancer and 76 healthy controls were enrolled. Molecular assessment of CTLA4 (rs231775& rs5742909) and CD28 (rs3116496) variants were determined with polymerase chain reaction restriction fragment length polymorphism techniques. Circulating levels of soluble forms of CTLA4 and CD28 were analyzed by ELISA. Results: Although no significant association was found between study groups, CTLA4 +49AA genotypic frequency, and sCTLA4 and sCD28 levels were higher in patients. Some clinicopathological features were also related with CTLA4 and CD28 variants and blood levels. Conclusion: While CTLA4 +49AA genotype is increased in patients with breast cancer, the CTLA4 -318T allele may have a prognostic value. In addition, sCTLA4 and sCD28 can be used for diagnostic purposes in patients with breast cancer

Association between Laryngeal Squamous Cell Carcinoma and Polymorphisms in Tumor Necrosis Factor Related Apoptosis Induce Ligand (TRAIL), TRAIL Receptor and sTRAIL Levels

The laryngeal squamous cell carcinoma (LSCC) is one of the most common malignant tumors occurring in the head and neck. Tumor necrosis factor related apoptosis induce ligand (TRAIL) and TRAIL-receptors (DR4, DR5, DcR1, DcR2) are known as important members of TRAIL-mediated biochemical signaling pathway. Associations between polymorphisms in these genes and clinicopathological characteristics of human laryngeal carcinoma are not well defined. This study therefore aimed to investigate a possible relationship among the TRAIL and TRAIL-DR4 polymorphisms and sTRAIL levels in the risk or progression of LSCC. A total of 99 patients with laryngeal cancer and 120 healthy subjects were enrolled in the study. DR4 C626G and TRAIL 1595 C/T genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis and sTRAIL levels were measured by ELISA. There were significant differences in the distribution of DR4 C626G genotypes and frequencies of the alleles between laryngeal cancer patients and controls (p<0.001) but not in TRAIL 1595 C/T. We found the increased frequency of the DR4 C626G homozygote CC genotype in patients than in controls (p<0.001). Haplotype analysis revealed that there was also a statistically significant relationship between TRAIL and TRAIL-DR4 polymorphisms and laryngeal cancer. Serum sTRAIL levels in the laryngeal patients with CC genotype who had advanced tumour stage were lower than those of patients with early tumor stage (p=0.014). Our findings suggest that DR4 C626G genotypes and sTRAIL levels might be associated with progression of laryngeal cancer in the Turkish population

Individual and Combined Effects of CTLA4-CD28 Variants and Oxidant-Antioxidant Status on the Development of Colorectal Cancer

Background: Colorectal cancer (CRC) is the third most frequent cancer worldwide. Research has revealed the contributions of the immune system and anti-inflammatory pathways in the development of cancer. The balance between cluster of differentiation 28 (CD28) and cytotoxic T-lymphocyte-associated protein 4 (CTLA4) signaling is important for the regulation of immune responses. The oxidant-antioxidant balance by sustaining redox control via several defense mechanisms is also an important factor for the progression of cancer. The aim of the present study was to determine the distribution of CTLA4/CD28 variants and oxidant-antioxidant status in patients with CRC. Materials and Methods: This study enrolled 80 patients with CRC and 115 healthy controls. We used a spectrophotometric assay to detect the levels of lipid peroxidation products malon dialdehyde (MDA) and lipid hydroperoxide (LHP), and measured the concentration of protein damage products, advanced oxidation protein products (AOPP) and protein carbonyl (PCO). Additionally, antioxidant levels were detected by measuring copper, zinc, superoxide dismutase (Zn-Cu SOD) and total thiol (T-SH) levels, and advanced glycation end-products (AGEs). The CTLA4 -318C>T, CTLA4 49A>G and CD28C>T genotypes were determined by using restriction enzymes. Results: AOPP and PCO levels were increased in patients with CRC as well as those of LHP, MDA and AGE, while the levels of antioxidants such as Cu-Zn SOD and T-SH were lower. Lower serum levels of CTLA4 and higher serum levels of CD28 were detected in patients and, an association of the CTLA4-318C/T polymorphism was found in patients with CRC. Conclusion: Our oxidative stress was increased in patients with CRC, suggesting the contribution of this disturbed oxidative status to serum CTLA4 and CD28 levels, and to the pathogenesis of CRC