Gene Expression Profile of Salivary Adenoid Cystic Carcinoma Associated with Perineural Invasion

Abstract

Adenoid cystic carcinoma (ACC) is a common salivary gland malignancy characterized by slow but progressive clinical course, proclivity for hematogenous spread and perineural invasion (PNI) that exhibits inherent resistance to complete surgical resection, systemic chemotherapy and conventional radiotherapy. The molecular alterations that underlie its PNI are poorly characterized. We report the combined use of laser capture microdissection (LCM) and high-throughput cDNA microarray to monitor in vivo gene expression profile of salivary ACC and to correlate the profile with PNI. Consecutive section staining with hematoxylin & eosin was applied to 15 cancerous tissues, among which 6 were judged as PNI. Pure cancer cells adjacent to the nerve tracts from 6 cancerous tissues judged as PNI were laser captured, and pure cancer cells from the same 6 tumors distant from the nerve tracts were also procured. Total RNA was extracted, amplified and subjected to cDNA microarray-based expression analysis. The patterns of gene expression were verified by quantitative real-time PCR and immunohistochemistry. As to the result of 6 arrays, a total of 53 genes were identified as being 2-fold or more differentially expressed in PNI cancer cell group as compared to non-PNI cancer cell control. Out of the 53 genes found consistently differentially expressed, 38 were up-regulated and 15 down-regulated. The combined use of LCM and cDNA microarray analysis provides a powerful new approach to monitor the in vivo molecular events of PNI in salivary ACC. These identified novel genes deserve further investigations to elucidate their clinicopathological significance.carcinoma, adenoid cystic; perineural invasion; microarray; laser capture microdissection; gene expression

Inhibition of CD146 gene expression via RNA interference reduces in vitro perineural invasion on ACC‐M cell

“…The expression pattern and the quantitative expression level of CD146 were validated by quantitative real‐time polymerase chain reaction (PCR) and immunohistochemistry. That means CD146 may play a potential important role in the pathobiology of ACC associated with PNI (19). So, we hypothesized that knockdown of CD146 would inhibit in vitro PNI on ACC‐M cell.…”

Lentiviral-mediated gene silencing of Notch-4 inhibits in vitro proliferation and perineural invasion of ACC-M cells

“…In SACC, a recent study suggested that Notch-4 activation contributes to SACC metastasis (24). In our previous microarray study, Notch-4 was found to play a potential important role in the pathobiology of SACC associated with PNI (25). Thus, we tested our hypothesis on whether knockdown of Notch-4 by short hairpin RNA (shRNA) inhibits the in vitro proliferation and PNI in ACC-M cells.…”

Exploring the potential of laser capture microdissection technology in integrated oral biosciences

“…The upregulated expression of COX‐2 and anti‐apoptotic protein Bcl2 in the luminal cells of pleomorphic adenoma was linked to tumor pathogenesis. A study was undertaken to analyze gene expression in adenoid cystic carcinoma (AdCC) to correlate it to perineural invasion by microdissecting cancer cells close to the nerve and distant from the nerve (Chen et al , ). This study implicated several novel genes responsible for perineural invasion in AdCC like melanoma cell adhesion molecule (MCAM), amphiregulin (AREG), meningioma expressed antigen 6 (MGEA6), N‐terminal caspase recruitment domain 12 (CARD12), peripheral myelin protein 22 (PMP22), taxol resistance‐associated gene 3 (TRAG3), MMP‐7, and nuclear transport factor 4 (NTF4) gene (Chen et al , ).…”

“…A study was undertaken to analyze gene expression in adenoid cystic carcinoma (AdCC) to correlate it to perineural invasion by microdissecting cancer cells close to the nerve and distant from the nerve (Chen et al , ). This study implicated several novel genes responsible for perineural invasion in AdCC like melanoma cell adhesion molecule (MCAM), amphiregulin (AREG), meningioma expressed antigen 6 (MGEA6), N‐terminal caspase recruitment domain 12 (CARD12), peripheral myelin protein 22 (PMP22), taxol resistance‐associated gene 3 (TRAG3), MMP‐7, and nuclear transport factor 4 (NTF4) gene (Chen et al , ). The authors found that melanoma‐associated gene (MAGE) family proteins (A2, A3, A4, and A9) and TRAG3, which cause DNA demethylation, are downregulated in AdCC with perineural invasion (Chen et al , ).…”