Proteome analysis of human gastric cardia adenocarcinoma by laser capture microdissection

<p>Abstract</p> <p>Background</p> <p>The incidence of gastric cardiac adenocarcinoma (GCA) has been increasing in the past two decades in China, but the molecular changes relating to carcinogenesis have not been well characterised.</p> <p>Methods</p> <p>In this study, we used a comparative proteomic approach to analyse the malignant and nonmalignant gastric cardia epithelial cells isolated by navigated laser capture microdissection (LCM) from paired surgical specimens of human GCA.</p> <p>Results</p> <p>Twenty-seven spots corresponding to 23 proteins were consistently differentially regulated. Fifteen proteins were shown to be up-regulated, while eight proteins were shown to be down-regulated in malignant cells compared with nonmalignant columnar epithelial cells. The identified proteins appeared to be involved in metabolism, chaperone, antioxidation, signal transduction, apoptosis, cell proliferation, and differentiation. In addition, expressions of HSP27, 60, and Prx-2 in GCA specimens were further confirmed by immunohistochemical and western blot analyses.</p> <p>Conclusion</p> <p>These data indicate that the combination of navigated LCM with 2-DE provides an effective strategy for discovering proteins that are differentially expressed in GCA. Such proteins may contribute in elucidating the molecular mechanisms of GCA carcinogenesis. Furthermore, the combination provides potential clinical biomarkers that aid in early detection and provide potential therapeutic targets.</p

Is it justified to ablate flat-type esophageal squamous cancer? An analysis of endoscopic submucosal dissection specimens of lesions meeting the selection criteria of radiofrequency studies

Endoscopic radiofrequency ablation (RFA) appears to be a safe and effective treatment for flat-type noninvasive squamous neoplasia of the esophagus. However, if RFA is applied to lesions containing invasive cancer (esophageal squamous cell carcinoma [ESCC]), histological features associated with lymph node metastases may remain undetected. In addition, extension of neoplasia down the ducts of esophageal submucosal glands (SMGs) may create a sheltered "niche" beyond the reach of ablation. To determine the RFA eligibility of flat-type ESCC. Retrospective analysis of prospectively collected data of ESCC patients. National Cancer Center Hospital, Tokyo, Japan. Patients with flat-type ESCC larger than 3 cm removed by endoscopic submucosal dissection (ESD). Three endoscopists involved in RFA studies in China reviewed endoscopic images to select lesions eligible for RFA. Corresponding ESD resection specimens were histologically examined. The presence of poor histological features (ie, invasion in m3 or deeper, poor tumor differentiation, or lymphovascular invasion) and the number of involved esophageal SMGs and ducts. Sixty-five lesions were included, 17 (26%) of which qualified as RFA eligible by RFA endoscopists. Interobserver agreement for this assessment was poor (κ = 0.09). Six of the 17 specimens (35%) showed relevant disease: 4 lesions invaded in the muscularis mucosae, 1 of which also showed lymphovascular invasion; 2 lesions showed extension of neoplasia into SMGs. Limited number of cases. RFA eligibility status was based on analysis of still images. One third of flat-type ESCC, deemed eligible for RFA, demonstrated histological features that are considered (relative) contraindications to endoscopic treatment. Because it appears difficult for endoscopists to identify low-risk ESCC, conservative use of RFA for flat-type ESCC is advocated until long-term follow-up data are availabl