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Publications (2)2.54 Total impact

  • Article: Proteomic analysis of differential protein expression by brain metastases of gynecological malignancies.
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    ABSTRACT: Brain metastases of gynecological malignancies are rare, but the incidence is increasing. Patients with brain metastases have a poor prognosis, therefore early detection and optimal management is necessary. In order to determine a new biomarker, we aimed to identify proteins that associated with brain metastases. We investigated proteins associated with brain metastases of gynecological malignancies in three patients who underwent surgical resection (stage IIb cervical cancer, stage Ib endometrial cancer, and stage IIIb ovarian cancer). Proteomic analysis was performed on formalin-fixed paraffin-embedded (FFPE) samples of the primary tumors and brain metastases, which were analyzed by liquid chromatography with tandem mass spectrometry. Thereafter, candidate proteins were identified by the Scaffold system and Mascot search program, and were analyzed using western blotting and immunohistochemistry. As a result, a total of 129 proteins were identified. In endometrial and ovarian cancers, western blotting revealed that the expression of alpha-enolase (ENO1) and triosephosphate isomerase (TPI-1) was higher and the expression of Transgelin-2 (TAGLN2) was lower in metastatic tumors than in primary tumors. On the other hand, the expression of TPI-1 and TAGLN2 was lower in metastatic tumors than in primary tumors in cervical cancer. Immunohistochemistry confirmed that ENO1 expression was elevated in the metastatic tumors compared with the primary tumors. In conclusion, the present study showed that FFPE tissue-based proteomics analysis can be powerful tool, and these findings suggested that ENO1, TPI-1, and TAGLN2 may have a role in the development and progression of brain metastasis from gynecological malignancies.
    Human Cell 03/2013; · 1.27 Impact Factor
  • Article: Heat shock protein 27 and p16 immunohistochemistry in cervical intraepithelial neoplasia and squamous cell carcinoma.
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    ABSTRACT: Heat shock protein 27 (hsp27) is expressed by squamous cell carcinoma of the uterine cervix. Results from an earlier study by our group indicted that hsp27 may be a diagnostic marker for cervical intraepithelial neoplasia (CIN) and carcinoma. p16 expression is known to be elevated in intraepithelial uterine cervical cancer and grades 2 and 3 lesions (CIN2, CIN3), but has also been reported to be negative in 5-20% of cervical cancer and CIN lesions. The aim of our study was to confirm immunohistochemically the expression of hsp27 and p16 in cervical lesions. Formalin-fixed, paraffin-embedded cervical tissue specimens obtained between 2002 and 2010 were investigated for hsp27 and p16 expression. Positive staining was detected for hsp27 in 63% of normal cervical tissues, 47% of CIN1 lesions, 75% of CIN2 lesions, 92% of CIN3 lesions, and 100% of squamous cell carcinomas (SCC); the corresponding rates for p16 positivity were 29, 47, 67, 92, and 75%, respectively. Positive staining for both hsp27 and p16 was observed in 6% of normal cervical tissues and in 19% of CIN1, 18% of CIN2, 85% of CIN3, and 75% of SCC specimens. Hsp27 or p16 positivity had a sensitivity of 95.6 or 84.7% and a specificity of 37.2 or 70.5%, respectively, for the identification of CIN3 or SCC lesions; when both hsp27 and p16 were assessed, both the sensitivity and specificity were improved. In conclusion, both hsp27 and p16 immunohistochemistry is a useful tool for the diagnosis of CIN3 lesions or cervical SCC.
    Human Cell 02/2012; 25(1):24-8. · 1.27 Impact Factor