The Role and Significance of Biomarker for Plasma G-CSF in Patients with Primary Lung Cancer / 결핵및호흡기질환

BACKGROUND: Biomarkers for cancer have several potential clinical uses, including the following: early cancer detection, monitoring for recurrence prognostication, and risk stratification. However, no biomarker has been shown to have adequate sensitivity and specificity. Many investigators have tried to validate biomarkers for the early detection and recurrence of lung cancer. To evaluate plasma G-CSF as such a biomarker, protein levels were measured and were found to correlate with the clinicopathological features of primary lung tumors. METHODS: Between December 2006 and May 2008, 100 patients with histologically-validated primary lung cancer were enrolled into this study. To serve as controls, 127 healthy volunteers were enrolled into this study. Plasma G-CSF levels were measured in lung cancer patients using the sandwich ELISA system (R & D inc.) prior to treatment. RESULTS: The mean plasma G-CSF levels were 12.2+/-0.3 pg/mL and 46.0+/-3.8 pg/mL (mean+/-SE) in the normal and in the cancer groups, respectively. In addition, plasma G-CSF levels were higher in patients with early lung cancer than in healthy volunteers (p<.001). Plasma G-CSF levels were higher in patients who were under 65 years old or smokers. Within the cancer group, plasma G-CSF levels were higher in patients with non small cell lung cancer than in patients with small cell lung cancer (p<.05). Overall, plasma G-CSF levels were shown to increase dependent upon the type of lung cancer diagnsosed. In the order from highest to lowest, the levels of plasma G-CSF tended to decrease in the following order: large cell carcinoma, squamous cell carcinoma, adenocarcinoma, and bronchioloalveolar carcinoma. Plasma G-CSF levels tended to be higher in patients with advanced TNM stage than in localized TNM stage (I, II

Calcium sensing receptor forms complex with and is up-regulated by caveolin-1 in cultured human osteosarcoma (Saos-2) cells

The calcium sensing receptor (CaSR) plays an important role for sensing local changes in the extracellular calcium concentration ([Ca2+]o) in bone remodeling. Although the function of CaSR is known, the regulatory mechanism of CaSR remains controversial. We report here the regulatory effect of caveolin on CaSR function as a process of CaSR regulation by using the human osteosarcoma cell line (Saos-2). The intracellular calcium concentration ([Ca2+]i) was increased by an increment of [Ca2+]o. This [Ca2+]i increment was inhibited by the pretreatment with NPS 2390, an antagonist of CaSR. RT-PCR and Western blot analysis of Saos-2 cells revealed the presence of CaSR, caveolin (Cav)-1 and -2 in both mRNA and protein expressions, but there was no expression of Cav-3 mRNA and protein in the cells. In the isolated caveolae-rich membrane fraction from Saos-2 cells, the CaSR, Cav-1 and Cav-2 proteins were localized in same fractions (fraction number 4 and 5). The immuno-precipitation experiment using the respective antibodies showed complex formation between the CaSR and Cav-1, but no complex formation of CaSR and Cav-2. Confocal microscopy also supported the co-localization of CaSR and Cav-1 at the plasma membrane. Functionally, the [Ca2+]o- induced [Ca2+]i increment was attenuated by the introduction of Cav-1 antisense oligodeoxynucleotide (ODN). From these results, in Saos-2 cells, the function of CaSR might be regulated by binding with Cav-1. Considering the decrement of CaSR activity by antisense ODN, Cav-1 up-regulates the function of CaSR under normal physiological conditions, and it may play an important role in the diverse pathophysiological processes of bone remodeling or in the CaSR- related disorders in the body.

The Emerging Role of Natural Killer Cells in Innate and Adaptive Immunity

In the early host defense system, effector function of natural killer (NK) cells results in natural killing against target cells such as microbe-infected, malignant, and certain allogenic cells without prior stimulation. NK cell cytotoxicity is selectively regulated by homeostatic prevalence between a repertoire of both activating and inhibitory receptors, and the discrimination of untransformed cells is achieved by recognition of major histocompatibility complex (MHC) class I alleles through inhibitory signals. Although it is well known that the bipotential T/NK progenitors are derived from the common precusor, functional mechanisms in terms of the development of NK cells remain to be further investigated. NK cells are mainly involved in innate immunity, but recent studies have been reported that they also play a critical role in adaptive immune responses through interaction with dendritic cells (DC). This interaction will provide effector functions and development of NK cells, and elucidation of its precise mechanism may lead to therapeutic strategies for effective treatment of several immune diseases.