A New Serum Biomarker for Lung Cancer - Transthyretin

Background and objective Lung cancer is the leading cause of cancer death worldwide and very few specific biomarkers could be used in clinical diagnosis at present. The aim of this study is to find novel potential serum biomarkers for lung cancer using Surface Enhanced Laser Desorption/Ionization (SELDI) technique. Methods Serumsample of 227 cases including 146 lung cancer, 13 pneumonia, 28 tuberculous pleurisy and 40 normal individuals were analyzed by CM10 chips. The candidate biomarkers were identified by ESI/MS-MS and database searching, and further confirmed by immunoprecipitation. The same sets of serum sample from all groups were re-measured by ELISA assay. Results Three protein peaks with the molecular weight 13.78 kDa, 13.90 kDa and 14.07 kDa were found significantlydecreased in lung cancer serum compared to the other groups and were all automatically selected as specific biomarkers by Biomarker Wizard software. The candidate biomarkers obtained from 1-D SDS gel bands by matching the molecular weight with peaks on CM10 chips were identified by Mass spectrometry as the native transthyretin (nativeTTR), cysTTR and glutTTR, and the identity was further validated by immunoprecipitation using commercial TTR antibodies. Downregulated of TTR was found in both ELISA and SELDI analysis. Conclusion TTRs acted as the potentially useful biomarkers for lung cancer by SELDI technique

Mitochondrial autophagy involving renal injury and aging is modulated by caloric intake in aged rat kidneys.

BACKGROUND: A high-calorie (HC) diet induces renal injury and promotes aging, and calorie restriction (CR) may ameliorate these responses. However, the effects of long-term HC and CR on renal damage and aging have been not fully determined. Autophagy plays a crucial role in removing protein aggregates and damaged organelles to maintain intracellular homeostasis and function. The role of autophagy in HC-induced renal damage is unknown. METHODS: We evaluated the expression of LC3/Atg8 as a marker of the autophagosome; p62/SQSTM1; polyubiquitin aggregates as markers of autophagy flux; Ambra1, PINK1, Parkin and Bnip3 as markers of mitophagy; 8-hydroxydeoxyguanosine (8-OHdG) as a marker of DNA oxidative damage; and p16 as a marker of organ aging by western blot and immunohistochemical staining in the kidneys of 24-month-old Fischer 344 rats. We also observed mitochondrial structure and autolysosomes by transmission electron microscopy. RESULTS: Expression of the autophagosome formation marker LC3/Atg8 and markers of mitochondrial autophagy (mitophagy) were markedly decreased in the kidneys of the HC group, and markedly increased in CR kidneys. p62/SQSTM1 and polyubiquitin aggregates increased in HC kidneys, and decreased in CR kidneys. Transmission electron microscopy demonstrated that HC kidneys showed severe abnormal mitochondrial morphology with fewer autolysosomes, while CR kidneys exhibited normal mitochondrial morphology with numerous autolysosomes. The level of 8-hydroxydeoxyguanosine was increased in HC kidneys and decreased in CR kidneys. Markers of aging, such as p16 and senescence-associated-galactosidase, were increased significantly in the HC group and decreased significantly in the CR group. CONCLUSION: The study firstly suggests that HC diet inhibits renal autophagy and aggravates renal oxidative damage and aging, while CR enhances renal autophagy and ameliorates oxidative damage and aging in the kidneys

Selective Expression of Calcium-Binding Protein S100A7 in Lung Cancer

Background and objective S100A7 is a member of S100 family and its overexpression has been previously associated with carcinogenesis of certain cancers. The aim of this study is to explore the expression of calcium-binding protein S100A7 in lung cancer. Methods In the present study, RT-PCR, Western-blot and immunohistochemistry were used to analyze the different expression of S100A7 in lung cancer tissues and paired noncancerous lung tissues. Results The specific expression of S100A7 was found in squamous cell carcinomas and large cell lung carcinomas, whereas it was not detected in adenocarcinomas, small cell carcinomas, other cell types of lung cancer and normal lung tissues as well as paired noncancerous lung tissues. Conclusion S100A7 was selectively expressed in squamous cell carcinomas and large cell lung carcinomas and may serve as a potential marker for lung cancer diagnosis

Bnip3, Ambra1 decreased in HC kidneys and increased in CR kidneys compared with CON kidneys.

<p>The expression of Bnip3 and Ambra1was analyzed by Western blotting in the kidneys of CON, CR, and HC Fischer 344 rats. <b>a:</b> The expression of Bnip3 and Ambra1 was detected by Western blotting. <b>b:</b>Quantitative analysis of the band density for Bnip3. <b>c:</b>Quantitative analysis of the band density for Ambra1. The protein expression data are presented as the mean ± SD (n  = 6). *p<0.05 vs. CON.CON, control animals; CR, calorie-restricted diet; HC, high-calorie diet.</p

The level of 8-OHdG was increased in HC kidneys and decreased in CR kidneys.

<p>Immunohistochemistry staining results for LC3 proteins and 8-OHdG in the kidneys of the CON, CR and HC Fischer 344 rats were scanned by a microscope. CON, control animals; CR, calorie-restricted diet; HC, high-calorie diet.</p

LC3 was decreased in HC kidneys and increased in CR kidneys compared with CON kidneys.

<p>LC3 expression was analysed by Western blotting in the renal tissues of the CON, CR and HC Fischer 344 rats. <b>a:</b> Theexpression of LC3-I and LC3-II proteins was detected by Western blot analysis.<b>b:</b> The ratio of the LC3-II to LC3-I bands was analyzed. The protein expression data are presented as the mean ± SD (n  = 6). *p<0.05 vs. CON.<b>c:</b> Immunohistochemistry staining results for LC3 proteins and 8-OHdG in the kidneys of the CON, CR and HC Fischer 344 rats were scanned by a microscope.CON, control animals; CR, calorie-restricted diet; HC, high-calorie diet.</p

The levels of p16 and SA-β-gal increased in HC kidneys and decreased in CR kidneys.

<p>The expression of the senescence biomarkers p16 and senescence-associated-galactosidase wasanalyzed in the kidneys of CON, CR, and HC Fischer 344 rats. <b>a:</b> Western blot results for p16 protein. <b>b:</b> Quantitative analysis of the band density for p16. The protein expression data are presented as the mean ± SD (n  = 6). *p<0.05 vs. CON. <b>c:</b>Senescence-associated-galactosidase staining (magnification ×400). Blue precipitation in the cytoplasm was observed in the senescent cells.CON, control animals; CR, calorie-restricted diet; HC, high-calorie diet.</p

The numbers of CON, CR and HC rats at the age of 3-month and 24-month.

<p>CON, control animals; CR, calorie-restricted diet; HC, high-calorie diet.</p