Focal adhesion kinase (p125 FAK ; 'FAK') is a tyrosine kinase that is localised to cellular focal adhesions and is associated with a number of other proteins, such as integrin adhesion receptors. We performed an immunohistochemical analysis of FAK protein expression to determine the relationship between FAK overexpression and clinicopathological factors in oesophageal squamous cell carcinoma (ESCC). We examined tissue specimens that had been removed from 91 patients with thoracic oesophageal cancer who had undergone surgery between 1983 and 2001. Immunohistochemical staining was performed by the standard streptavidin -biotin method. Seven human ESCC cell lines -TE-1, TE-2, TE-8, TE-13, TE-15, TT, and TTn -and one immortalized human keratinocyte cell line -HaCaT -were used in Western blot analysis. Immunostaining of FAK was seen in the cytoplasm of cancer cells, particularly in cells located in the invasive fronts of cancer nests. FAK overexpression was detected in 54 of the 91 patients (59.3%). Significant correlations were observed between FAK overexpression and cell differentiation (P ¼ 0.0057), depth of tumour invasion (P ¼ 0.0023), presence of regional lymph node metastasis (P ¼ 0.0097), number of lymph node metastases (P ¼ 0.0026), and disease stage (P ¼ 0.012). The survival rates of patients with FAK-overexpressing cancer were significantly lower than those of patients without FAK-overexpression cancer (P ¼ 0.006). The 5-year survival rate of patients without FAK overexpression was 69%, whereas that of patients with FAK overexpression was 38%. On Western blot analysis, FAK was expressed at a high level in TE-1, TE-8, TE-15, and TT cells, at a moderate level in TE-2 and TTn cells, and at a low level in TE13 and HaCaT cells. FAK phosphorylation at tyrosine 397 was demonstrated in proportion to the intensity of FAK in all cell lines except TE15 and HaCaT. In conclusion, FAK overexpression of ESCC was related to cell differentiation, tumour invasiveness, and lymph node metastasis. Consequently, patients with ESCC who had FAK overexpression had a poor prognosis.
BACKGROUNDThe purpose of the current study was to assess whether [18F]fluorodeoxyglucose positron emission tomography (FDG‐PET) provides incremental value (e.g., additional information on lymph node involvement or the presence of distant metastases) compared with computed tomography (CT) in patients with esophageal carcinoma.METHODSThe authors examined 149 consecutive patients with thoracic esophageal carcinoma. Eighty‐one patients underwent radical esophagectomy without pretreatment, 17 received chemoradiotherapy followed by surgery, 3 underwent endoscopic mucosal resection, and the remaining 48 patients received definitive radiotherapy and chemotherapy. The diagnostic accuracy of FDG‐PET and CT was evaluated at the time of diagnosis.RESULTSThe primary tumor was visualized using FDG‐PET in 119 (80%) of 149 patients. Regarding lymph node metastases, FDG‐PET had 32% sensitivity, 99% specificity, and 93% accuracy for individual lymph node group evaluation and 55% sensitivity, 90% specificity, and 72% accuracy for lymph node staging evaluation. PET exhibited incremental value over CT with regard to lymph node status in 14 of 98 patients who received surgery: 6 patients with negative CT findings were eventually shown to have lymph node metastases (i.e., they had positive PET findings and a positive reference standard [RS]); 6 patients with positive CT findings were shown not to have lymph node metastases (i.e., they had negative PET findings and a negative RS); and 2 patients were shown to have cervical lymph node metastases in addition to mediastinal or abdominal lymph node metastases. Among the remaining patients, PET showed incremental value over CT with regard to distant organ metastases in six patients. The overall incremental value of PET compared with CT with regard to staging accuracy was 14% (20 of 149 patients).CONCLUSIONSFDG‐PET provided incremental value over CT in the initial staging of esophageal carcinoma. At present, combined PET‐CT may be the most effective method available for the preoperative staging of esophageal tumors. Cancer 2005. © 2004 American Cancer Society.
The CDKN2 gene encodes two structurally different proteins: a cyclin-dependent kinase inhibitor, p16, which regulates retinoblastoma protein (pRb)-dependent G1 arrest, and a cell cycle inhibitor, p14ARF, which blocks MDM2-induced p53 degradation resulting in an increase in p53 levels that leads to cell cycle arrest. Recent studies have revealed that expression of p16 and p14ARF is influenced markedly by the status of pRb and p53, and p16 overexpression has been demonstrated in cervical neoplasia because of functional inactivation of pRb by the human papillomavirus (HPV) E7 protein. To clarify the p14ARF status and the relationship between p16/p14ARF and other cell cycle molecules in cervical carcinogenesis, immunohistochemical analysis of p16, p14ARF, p53 and MDM2 was performed on 65 samples of cervical and genital condylomatous and neoplastic lesions, including nine HPV-negative tumors. In most cervical cancers and preneoplastic lesions with HPV infection of high and intermediate risk, a marked overexpression of p14ARF as well as the p16 protein (i.e. dotted nuclear immunostaining) was observed. All condyloma acuminata except one and low-grade dysplasia with HPV infection of low risk, such as HPV 6, immunohistochemically showed completely negative staining for p14ARF, also seen in non-neoplastic and mesenchymal cells. Our results clearly show that the mode of p14ARF overexpression in cervical neoplastic cells with HPV association differs from that in cancers of other organs without HPV association, and the p14ARF overexpression may be attributable to a negative feedback result in the functional inactivation of the pRb and p53 proteins by HPV oncoproteins.
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