Chiao-Ying Lin

Overexpression and Amplification of Aurora-A in Hepatocellular Carcinoma

Purpose: Aurora-A/STK15/BTAK, a centrosome-associated serine/threonine kinase, has been shown to induce chromosomal instability, leading to aneuploidy and cell transformation. The purpose of this study was to investigate the expression and amplification of Aurora-A in hepatocellular carcinoma (HCC). Experimental Design: Aurora-A mRNA levels were measured in 224 HCCs and 199 paired nontumorous liver tissues by reverse transcription-PCR. Aurora-A mRNA and protein levels of 8 were also measured by reverse transcription-PCR and Western blot hybridization in 8 liver cancer cell lines. Amplification of Aurora-A was determined by Southern blot hybridization in 99 cases. Results: Aurora-A was overexpressed in 137 of 224 (61%) HCCs and all 8 of the cell lines. Overexpression of Aurora-A was associated with high-grade (grade II-IV), and high-stage (stage IIIB-IV) tumors, p53 mutation, infrequent β-catenin mutation, and poor outcome. Aurora-A overexpression and p53 mutation acted synergistically toward poor prognosis. Amplification of Aurora-A was detected only in 3 HCCs. Conclusion: The results show that Aurora-A is overexpressed frequently in HCC, and correlated with high grade and high stage, indicating that overexpression of Aurora-A plays a role in the development and progression of HCC.

Expression of the c-kit protein is associated with certain subtypes of salivary gland carcinoma

The c-Kit protein, a receptor type tyrosine kinase that plays an important role in the development of hematopoietic cells, melanocytes, and germ cells, is expressed in mastocytosis, gastrointestinal stromal cell tumors (GISTs), germ cell tumors, and several other tumors. Gain-of-function mutations in exon 11 and exon 17 have been shown as a mechanism of c-kit activation in some tumors. To study the role of c-kit in salivary gland carcinomas, we analyzed the c-kit protein expression in 79 carcinomas of major and minor salivary glands by immunohistochemistry. Although varying in intensity of staining, c-kit expression was identified very often in adenoid cystic carcinomas (20/25), lymphoepithelioma-like carcinomas (6/6) and myoepithelial carcinomas (2/2), but not in other types of salivary gland carcinoma (0/46), P<0.00001. By DNA sequencing, genetic alteration of c-kit juxtamembrane domain (exon 11) and tyrosine kinase domain (exon 17) was not found in all the three types of salivary carcinoma that had c-kit protein expression. In conclusion, c-kit protein overexpression is involved in the pathogenesis of certain types of salivary gland carcinoma, but mutation of the gene is not the mechanism of c-kit activation.

Histone deacetylase 2 expression predicts poorer prognosis in oral cancer patients

Histone deacetylase 2 (HDAC2) has been implicated in the development and progression of several human tumors. We immunohistochemically examined the expression of HDAC2 protein in 20 cases of oral epithelial dysplasia (OED) and 93 cases of oral squamous cell carcinoma (OSCC). Positive HDAC2 nuclear staining was observed in 80 of the 93 (86.02%) cases of SCC and 11 of the 20 (55%) cases of ED. The labeling index (LI) for HDAC2 nuclear staining increased significantly from ED (25.8+/-26.5%) to SCCs (59.8+/-28.5%) (p<0.001). No significant correlation was found between the HDAC2 expression level and patients age, sex, oral habits in oral SCC patients. However, cancer with advanced stage, larger tumor size, or positive lymph node metastasis had higher level of HDAC2 protein expression. Kaplan-Meier curves showed oral SCC patients with high HDAC2 expression (LI>50%), advanced stage, larger tumor size, or positive lymph node metastasis had significantly shorter overall survival (p=0.0158, 0.0267, 0.0029 and 0.02514, respectively by log-rank test) than others. The results of this study show for the first time that overexpression of the HDAC protein is a frequent event in oral cancer and could be used as a prognostic factor in oral SCC.

Cadherin-17 is a useful diagnostic marker for adenocarcinomas of the digestive system

Cadherin-17, also called liver-intestine cadherin, is a calcium-dependent transmembrane glycoprotein that mediates cell–cell adhesion in intestinal epithelium. Expression of cadherin-17 was reported in gastric, pancreatic, and colorectal adenocarcinomas but not in other tumors. Whether cadherin-17 can be used as a marker for diagnosis of cancers is still unclear. In this study, we used immunohistochemical methods to stain cadherin-17 in tissue arrays containing most normal tissues and 518 carcinomas from many anatomic sites. Among normal tissues, the expression of cadherin-17 was limited to epithelial cells of small intestine and colon. Colorectal adenocarcinomas showed staining in 96% of cases and most of them had strong and diffuse staining. Gastric, pancreatic, and biliary adenocarcinomas showed diffuse or scattered staining in about 25–50% of cases. Fewer than 1% of carcinomas outside the digestive system were positive for cadherin-17. When a two-marker, Cadherin-17/cytokeratin 7, profile was used, 37 of 38 (97%) cadherin-17(+)/cytokeratin 7(−) tumors were colorectal adenocarcinomas; 49 of 56 (86%) cadherin-17(+)/cytokeratin 7(+) tumors were gastric, pancreatic, or biliary adenocarcinomas. Our results show that cadherin-17 is a useful immunohistochemical marker for diagnosis of adenocarcinomas of the digestive system.

Nuclear localization of annexin A1 is a prognostic factor in oral squamous cell carcinoma.

To investigate whether annexin A1 (ANXA1) expression is a marker in predicting the prognosis of oral cancer patients.

Expression of cyclin A is related to progression of oral squamous cell carcinoma in Taiwan.

Cyclin A is required for DNA synthesis during the S phase and progression through the G2/M transition. Increased expression of cyclin A protein has been correlated with poor prognosis in a variety of human tumors. To investigate the possible influence(s) of cyclin A protein on the progression and prognosis of oral squamous cell carcinomas (SCCs) in Taiwan. We examined the expression of cyclin A in oral SCC, epithelial dysplasia (ED) and normal oral mucosa (NOM) by immunohistochemistry using antibodies to cyclin A. Results and Conclusions. The mean labeling indices (LI) in NOM, ED and SCCs were 7.0+/-3.1%, 12.1+/-3.9% and 21.3+/-12.3%, respectively. The cyclin A LI for oral SCCs was significantly higher than that for NOM (P=0.002) or ED (P<0.001). In addition, a high LI for cyclin A was found to correlate with advanced stage (P=0.0048), larger tumor size (P=0.0017), lymph node involvement (P=0.0006) and cancer recurrence (P<0.0001). The Kaplan-Meier analysis showed patients with tumors containing more than 15% cyclin A-positive cells had significantly shorter overall survival than those with tumors containing less than 15% cyclin A-positive cells (P<0.00001). These results indicate that overexpression of cyclin A protein is associated with tumor progression and patient prognosis for oral SCC.

Expression of Cyr61 (CCN1) in human oral squamous cell carcinoma: An independent marker for poor prognosis.

Cysteine‐rich 61 (Cyr61 [CCN1]) has disparate functions in tumorigenesis that are dependent on the cell types. The aim of the study was to investigate its role in the growth of oral squamous cell carcinoma (SCC).

Carbonic anhydrase VI: a novel marker for salivary serous acinar differentiation and its application to discriminate acinic cell carcinoma from mammary analogue secretory carcinoma of the salivary gland

Carbonic anhydrase VI (CA6) is present in serous acinar cells of human salivary glands. The aim of this study was to investigate the diagnostic utility of CA6 in differentiating acinic cell carcinoma (AciCC) from its morphological mimic mammary analogue secretory carcinoma (MASC) of the salivary gland.