Analysis of differentially expressed proteins in normal cervix, cervical intraepithelial neoplasia and cervical squamous carcinoma tissues / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To explore the differentially expressed proteins in normal cervix, cervical intraepithelial neoplasia (CIN) and squamous cervical carcinoma (SCC) tissues by differential proteomics, and to provide a basis for studies on CIN molecular pathogenesis, clinical diagnosis and treatment.</p><p><b>METHODS</b>Uterine cervical tissue specimens from the patients treated between August 2008 and September 2009 in the Department of Oncology of Beijing Obstetrics and Gynecology Hospital were collected. There were samples of normal cervix (n = 9), CIN (n = 23, CIN I = 7, CIN II = 8, CIN III = 8) and SCC (n = 7). 2-D DIGE and DeCyder software were used to detect the differentially expressed protein-spots. Then MALDI-TOF/TOF MS was used to analyze the differentially expressed proteins. Collect normal cervix(n = 20), CIN (n = 60) and SCC (n = 20), immunohistochemistry (IHC) and Western blot were used to verify the differentially expressed proteins of S100A9 (S100 calcium-binding protein A9) , eEF1A1 (eukaryotic elongation factor 1-alpha-1) and PKM2 (pyruvate kinase isozymes M2) among the normal cervix, CIN and SCC tissues. Immunohistochemistry was used to detect the differentially expressed S100A9, eEF1A1 and PKM2 in the cervical tissues.</p><p><b>RESULTS</b>2D gel electrophoresis images with high resolution and good repeatability were obtained. Forty-six differentially expressed proteins (27 were up-regulated and 19 were down-regulated) were selected among the normal, CIN, and SCC, and 26 proteins were successfully identified. Immunohistochemistry showed that protein S100A9 was mainly expressed in the cytoplasm, and its positive expression rate was 20.0% in normal cervical mucosa, 70.0% in CIN, and 100.0% in squamous cell carcinoma, with a significant difference between them (P = 0.006). eEF1A1 was mainly expressed in the cell plasma. Its positive expression rate was 70.0% in normal cervix, 73.3%in CIN and 60.0% in SCC tissues, with a non-significant difference between them (P = 0.758). The protein PKM2 was mainly expressed in the cell nuclei. Its positive expression rate was 100.0% in normal cervix, 93.3% in CIN and 75.0% in SCC tissues, showing a difference close to statistical significance (P = 0.059) between them. The results of Western blot were similar with that of immunohistochemical examination.</p><p><b>CONCLUSIONS</b>There are differentially expressed proteins among normal cervix, CIN and SCC. S100A9, eEF1A1 and PKM2 may become candidate markers for early diagnosis of cervical cancer and new targets for therapy. It also provides a further basis for studies of the pathogenetic mechanism of CIN developing to cervical cancer.</p>

Comparison of three methods of protein extraction from Dermatophagoides pteronyssinus for two-dimensional electrophoresis / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To explore an effective method of Dermatophagoides pteronyssinus protein extraction suitable for two-dimensional electrophoresis (2-DE) analysis.</p><p><b>METHODS</b>The extracts of Dermatophagoides pteronyssinus were prepared with Coca's solution, lysis buffer of 2-DE, and Trizol reagent, respectively. Bicinchoninic acid (BCA) assay was used to determine the total protein concentration of the samples. The efficiency of different protein extraction methods were evaluated with 2-DE analysis.</p><p><b>RESULTS</b>The concentrations of extracted protein by methods of Coca's solution, lysis buffer, and Trizol reagent were 0.63 g/L, 0.90 g/L, and 0.80 g/L, respectively. The 2-DE analysis results showed that some protein spots in low molecular weight (LMW) range could be detected with the Coca's solution method. With the lysis buffer of 2-DE method, more protein spots in LMW range could be detected, while the medium molecular weight (MMW) protein spots were absent. Several MMW protein spots (174-178 kD and 133 kD) and more LMW protein spots were detected with Trizol reagent method.</p><p><b>CONCLUSIONS</b>Among Coca's solution, lysis buffer of 2-DE, and Trizol reagent, the concentration of extracted protein of Dermatophagoides pteronyssinus by lysis buffer of 2-DE is the highest. However, most protein components of Dermatophagoides pteronyssinus purified mite bodies can be extracted by Trizol reagent, which may generally reflect the whole profile of Dermatophagoides pteronyssinus allergens.</p>

Analysis of serum biomarkers of ovarian epithelial cancers based on 2-DE DIGE and MALDI TOF/TOF / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To find new serum tumor markers for ovarian epithelial cancers by 2-DE DIGE and MALDI-TOF/TOF proteomic methods, in order to improve the diagnostic sensitivity and specificity.</p><p><b>METHODS</b>Serum samples from 103 cases of ovarian epithelial cancers, 60 cases of healthy women, 63 cases of benign ovarian tumors and 63 cases of benign pelvic diseases were collected. Sera of 20 cases of ovarian epithelial cancers (A), 20 cases of ovarian benign tumors (B), 20 cases of pelvic benign diseases (C) and 20 cases of health control (D) were matched by age and pooled, respectively. After depletion of high abundance serum albumin and IgG, the samples were assayed by 2-DE DIGE. The test was repeated three times. Analysis with DeCyder software revealed significant differential protein spots which were identified by MAIDI-TOF/TOF. Western blot and ELISA were used to validate the candidate serum markers.</p><p><b>RESULTS</b>1) There were 41 proteins having significant differences between the groups. MAIDI-TOF/TOF successfully identified 28 proteins. Haptoglobin (Hp) was the most significantly up-regulated protein, and transferrin (Tf) was the most significantly down-regulated protein. 2) Western blot and ELISA proved that there were significant differences in Hp and Tf between ovarian epithelial cancers and normal controls (P = 0.000), between ovarian epithelial cancers and ovarian benign tumors (P = 0.000), between ovarian epithelial cancers and benign pelvic disease sera (P = 0.000). 3) CA125 + Hp + Tf combined detection of ovarian cancer had higher sensitivity and specificity than CA125, Hp or Tf detection alone.</p><p><b>CONCLUSION</b>Hp and Tf are differently expressed in the sera of patients with ovarian epitheliual cancers. They can be used as serum biomarkers for ovarian epithelial cancers. CA125 + Hp + Tf combined detection may improve the sensitivity and specificity of diagnosis of ovarian epithelial cancers.</p>

Analysis of the proteomic changes of the serum of the Smad3 targeted deficient mice / 生物工程学报

We have studied the proteomic changes of the serum of the Smad3 targeted deficient mice using 2-DE and PMF approaches. 7 proteins expressed at different level in wild type mice and the Smad3 deficient mice were identified. These results would benefit the research on diagnosis and therapy of osteoarthritis and provided clues to studying the important function of Smad3 mediated TGF-beta signals during the skeletal development.