Clinical Significance of Focal Adhesion Kinase in Resectable Pancreatic Cancer

Abstract

Focal adhesion kinase (FAK) is a non-receptor, cytoplasmic protein tyrosine kinase that is involved in the regulation of cellular signaling, migration, apoptosis, and cell cycle progression. Previous reports have shown that FAK is expressed in various kinds of cancer tissues and cancer cell lines; however, no information is available about human pancreatic carcinoma specimens. Tissue such specimens were obtained from 50 patients who underwent pancreatic resection for pancreatic invasive ductal carcinoma at our institute from 1996 to 2002. Immunohistochemical analysis of FAK was performed in the resected specimens. Focal adhesion kinase expression in seven human pancreatic cancer cell lines was analyzed by reverse transcription polymerase chain reaction (PCR) analysis and Western blot analysis. Focal adhesion kinase expression was detected in 24 of 50 cases (48%). There was a statistically significant correlation between FAK expression and tumor size (P=0.004), although FAK expression did not significantly correlate with other factors such as tumor histological grade, lymph node metastasis, distant metastasis, histological stage, and overall survival. Reverse transcription PCR analysis and Western blot analysis showed that FAK was expressed in all seven pancreatic cancer cell lines. Focal adhesion kinase expression was not directly related to clinicopathological factors except tumor size in pancreatic carcinoma. Focal adhesion kinase expression may not be a prognostic marker for pancreatic cancer patients.

Increased Expression of Tissue Transglutaminase in Pancreatic Ductal Adenocarcinoma and Its Implications in Drug Resistance and Metastasis

“…Increased FAK expression is frequently associated with malignant or metastatic disease and poor patient prognosis (24)(25)(26)(27)(28)(29)(30). FAK expression is increased in various tumors, such as those of the breast, colon, thyroid, head and neck, ovaries, liver, esophagus, and pancreas (24)(25)(26)(27)(28)(29)(30) Fig. 4).…”

Paradoxical roles of FAK in tumor cell migration and metastasis

“…For instance, FAK expression correlates with pancreatic tumor size, but not with tumor grade, metastasis or overall survival. 57 FAK overexpression is not restricted to the invasive phenotype of breast carcinomas but rather appears to be a marker for malignant transformation. 58 These studies suggest that FAK might have different roles in different tumors.…”

Focal adhesion kinase serves as a marker of cervical lymph node metastasis and is a potential therapeutic target in tongue cancer

“…FAK overexpression has been shown in many solid carcinomas, including breast, colon, prostate, head and neck, liver, stomach, and ovary. Furthermore, FAK overexpression has been correlated with the invasive potential of a tumor and lymph node metastasis (Cance et al 2000;Canel et al 2006;Furuyama et al 2006;Miyazaki et al 2003;Theocharis et al 2002;Watermann et al 2005); whereas, reduced expression of FAK was found in liver metastases compared with matched primary tumors (Ayaki et al 2001). In agreement with this study, weak expression of FAK in patients with cervical cancer is speciWcally correlated with pelvic lymph node metastasis (Gabriel et al 2006).…”