The First Survey of Forensically Important Entomofauna Collected from Medicolegal Autopsies in South Korea.

Forensic entomology applies insect evidence to legal problems such as the estimation of minimum postmortem interval (mPMI). For this purpose, knowledge of the insect fauna that are attracted to human cadavers in each geographic region is a prerequisite. Despite many studies investigating the insect fauna attracted to meat, there has been no survey of the entomofauna on human cadavers in the East Asian temperate climate zone, particularly in Korea. Therefore, this study reports the entomofauna collected from medicolegal autopsies in northeastern Seoul and its suburbs. Insect samples were collected from 35 medicolegal autopsies in 2010, 2011, and 2013. Molecular and morphological methods were utilized for taxonomic identification. Among 1398 individual samples belonging to 3 orders, 13 families, 18 genera, and 32 species, the dominant family and species were Calliphoridae and Lucilia sericata, respectively. Despite its limited scale, this study provides a snapshot of the general entomofauna that are attracted to human cadavers in this region.

The role of serum response factor in hepatocellular carcinoma: an association with matrix metalloproteinase.

Serum response factor (SRF) regulates tran-scription of immediate early genes and triggers proliferation, migration and differentiation in several types of cells. Matrix metalloproteinases (MMPs), a group of zinc-dependent endopeptidases, play a crucial role in tumor invasion and metastasis. However, expression of SRF and its association with MMPs in hepatocellular carcinoma (HCC) have not been elucidated. We examined the expression levels of SRF, MMP-2 and MMP-9 in HCC tissues using Western blot assay. We also examined the effect of SRF on MMP expression and enzyme activity in HCC by transfection of SRF cDNA in HLE cells. Protein expression of SRF, MMP-2 and MMP-9 showed a significant increase in HCC tissues, compared with those of corresponding non-tumor tissues. High SRF expressing HCC tissues showed higher levels of expression of MMP-2 and MMP-9, compared with low SRF expressing HCC tissues. In addition, overexpression of SRF in HLE cells led to increased levels of expression of mRNA and protein, as well as increased enzyme activity of MMP-2 and MMP-9. Overexpression of SRF also led to significantly enhanced migration of HLE cells. These results suggest that overexpression of SRF in HCC may play an important role in tumor cell migration and invasion through upregulation of MMP-2 and MMP-9.

Concurrent large cell neuroendocrine carcinoma and adenocarcinoma of the ascending colon: a case report.

Large cell neuroendocrine carcinomas of the colon are rare and represent only a small percentage of all colonic endocrine tumors. Here, we report a case of a colonic large cell neuroendocrine carcinomas concurrent with a colonic adenocarcinoma. A 70-year-old man presented with acute abdominal pain. A spiral computed tomography scan of the abdomen revealed eccentric wall thickening on the ascending colon. An explorative laparotomy and a right hemicolectomy were performed. Grossly, two separated masses were observed in the proximal ascending colon. One was a 7.4 × 5.1 cm ulcerative fungating lesion, and the other was a 2.8 × 1.9 cm polypoid lesion. Microscopically, the ulcerative fungating lesion showed a well-differentiated neuroendocrine morphology with necrosis and increased mitosis. Most of the tumor cells had large, vesicular nuclei with eosinophilic nucleoli, variable amounts of eosinophilic cytoplasm, and immunoreactivity for chromogranin A and synaptophysin. The polypoid lesion was a well-differentiated adenocarcinoma that had invaded the submucosa. We diagnosed these lesions as a concurrent large cell neuroendocrine carcinoma and an adenocarcinoma of the ascending colon.

Expression of DBC1 and SIRT1 is associated with poor prognosis for breast carcinoma.

Recently, it has been reported that SIRT1 and DBC1 may be involved in the development of tumors and predict poor survival in some cancers. However, their exact role is not clear. Therefore, we investigated the expression status and clinical significance of DBC1 and SIRT1 expression in breast carcinomas. We evaluated the immunohistochemical expression of DBC1, SIRT1, and p53 using a 3-mm core from 122 patients with breast cancer for tissue microarray. Positive expression of DBC1 and SIRT1 were seen in 71% and 67% of patients, respectively. In the patients with breast cancer, overall, expression of DBC1 and SIRT1 was significantly associated with distant metastatic relapse and shorter relapse-free survival and overall survival by univariate analysis. Tumor stage and DBC1 and SIRT1 expression were also independent prognostic factors by multivariate analysis. Among the patients who had received chemotherapy, DBC1 and SIRT1 expression was significantly associated with distant metastatic relapse and shorter survival by univariate analysis. DBC1 expression was also associated with distant metastatic relapse and shorter survival in patients who had received endocrine therapy, according to univariate and multivariate analysis. In conclusion, this study shows that expression of DBC1 and SIRT1 is a significant prognostic indicator for breast carcinoma patients.

The role of serum response factor in hepatocellular carcinoma: implications for disease progression.

Serum response factor (SRF) regulates transcription of the immediate early genes and triggers proliferation, migration and differentiation in several types of cells. We examined the role of SRF in HCC by transfecting the SRF cDNA in HLE cells and the SRF anti-sense cDNA in sarcomatoid HCC cells. The overexpression of SRF in the HLE cells significantly increased the cell growth and proliferation. Overexpression of SRF increased actin polymerization of the HCC cells and induced morphologic changes. The mesenchymal markers vimentin, N-cadherin and RhoA were highly expressed in the SRF-transfected HLE cells. Furthermore, the overexpression of SRF in the HLE cells increased the expression levels of the active form of the beta-catenin and Wnt/beta-catenin target genes, such as c-myc and cyclin D1. The overexpression of SRF significantly enhanced the cell migration and invasiveness of HCC cells. Conversely, inhibition of the SRF expression in the sarcomatoid SH-J1 cells by the SRF anti-sense cDNA significantly decreased migration and invasion through the attenuated expression of mesenchymal markers and the proteins involved in the Wnt/beta-catenin pathway. These results indicate that the overexpression of SRF in HCC cells modulates the Wnt/beta-catenin pathway, and this plays an important role in HCC progression.

The expression and role of serum response factor in papillary carcinoma of the thyroid.

Serum response factor (SRF) is a transcription factor of the MADS box family. SRF is involved in various cellular processes such as expression of immediate early and tissue-specific genes, cell proliferation, differentiation and apoptosis. The expression of SRF in papillary thyroid carcinoma (PTC) and its role have not been investigated, forming the basis for this study. Surgical specimens of 63 conventional PTCs along with 30 follicular adenoma, 30 adenomatous hyperplasia and 9 anaplastic carcinoma specimens were obtained from the surgical archives. The expression of SRF was determined by the use of immunohistochemical staining. We also investigated the expression level of SRF and an SRF target gene, c-fos in fresh PTC tissues and thyroid cancer cell lines (NPA, FRO and ARO) by Western blot analyses. In addition, we examined the role of SRF in PTC by overexpresion of SRF in the NPA cell line. SRF was mainly expressed in cancer cells, showing a strong nuclear and/or cytoplasmic staining in PTC. SRF was expressed in 50 of 63 cases of papillary carcinoma (79%), 18 of 30 cases of follicular adenoma (60%), 10 of 30 cases of nodular hyperplasia (33%) and 6 of 9 cases of anaplastic carcinoma (67%). The expression level of SRF was significantly up-regulated in PTC (combined staining score of 5.21+/-0.43) and anaplastic carcinoma (5.67+/-1.45) compared to that of follicular adenoma (2.30+/-0.44) (P<0.001), or adenomatous goiter (1.13+/-0.28) (P<0.001). Western blot analyses showed an increased expression of the spliced form of SRF protein and c-Fos protein in PTC as compared to non-tumor thyroid tissues. SRF expression correlated with the tumor size of the PTCs (P<0.05). Overexpression of SRF in papillary carcinoma cells enhanced cell motility and invasiveness. Our results indicate that the altered expression of SRF in papillary carcinoma cells may play an important role in PTC carcinogenesis and progression.

Expression and prognostic significance of SIRT1 in ovarian epithelial tumours.

AIMS: Sirtuin1 (SIRT1) is a nicotinamide adenine dinucleotide-dependent deacetylase. Recently, some studies have suggested that SIRT1 could be over-expressed in breast, prostate and colon cancers and up-regulated SIRT1 inactivates p53 by deacetylation. Therefore, we investigated the prevalence and the prognostic impact of SIRT1 and p53 expression in ovarian epithelial tumours. METHODS: Immunohistochemical expression of SIRT1 and p53 were evaluated using tissue microarray in 40 cases of benign epithelial tumours, 36 cases of borderline tumours, and 90 cases of malignant tumours. RESULTS: Expression of SIRT1 was significantly increased in malignant epithelial tumours compared to benign and borderline epithelial tumours (p < 0.001). In particular, a high proportion of serous carcinoma expressed SIRT1 (86%, 55/64 cases). Despite the frequent expression of SIRT1 in malignant ovarian epithelial tumours, serous carcinomas of high FIGO stage showed less frequent SIRT1 expression compared to that of low stage serous carcinomas (p = 0.029). Moreover, increased expression of SIRT1 in serous carcinoma correlated with increased overall survival by univariate (p = 0.014) and multivariate analyses. CONCLUSIONS: Over-expression of SIRT1 may play an important role in the early stage of ovarian carcinogenesis.

Serum response factor enhances liver metastasis of colorectal carcinoma via alteration of the E-cadherin/beta-catenin complex.

Serum response factor (SRF) is a transcription factor that controls cell growth, differentiation, and tumor progression as well as muscle development and function. Reduced expression of cell adhesion molecules has been reported to be associated with tumor metastasis. The aim of this study was to evaluate the expression and a role of SRF in liver metastasis of primary colorectal carcinomas. We examined the expression of SRF, E-cadherin, and beta-catenin by the use of immunochemical staining in 43 cases as a set of primary colorectal carcinomas and liver metastases. We also examined the role of SRF in colorectal carcinoma by overexpression of SRF in a colon cancer cell line. In metastatic carcinoma surgical samples, there was a marked increased expression of SRF as compared to expression in primary colorectal carcinoma surgical samples (P<0.05). E-cadherin expression was significantly decreased in metastatic liver carcinoma samples as compared to primary colorectal carcinoma samples (P<0.001). Frequent nuclear translocation of beta-catenin protein in primary and metastatic carcinoma cells was observed. Overexpression of SRF in SW480 cells resulted in a decreased expression of E-cadherin and an increased expression of non-phosphorylated nuclear beta-catenin. Overexpression of SRF in colorectal carcinoma cells enhanced cell motility and invasiveness. These results indicate that overexpression of SRF in colorectal carcinoma cells is associated with modulation of E-cadherin/beta-catenin expression and may play an important role in colorectal cancer metastasis.

SIRT1 expression is associated with poor prognosis of diffuse large B-cell lymphoma.

Sirtuin1 (SIRT1) is a nicotinamide adenine dinucleotide-dependent deacetylase. Recently, it is suggested that SIRT1 may be involved in the development of malignant tumors including mouse lymphoma. Therefore, we investigated the prevalence and the prognostic impact of SIRT1 expression in diffuse large B-cell lymphoma (DLBCL). Immunohistochemical expression of SIRT1, p53, bcl2, CD10, bcl6, and multiple myeloma-1 (MUM1) were evaluated by using a 2 mm core from 104 DLBCL patients for tissue microarray. Positive expression of SIRT1 was seen in 74% (77/104) of patients. In total DLBCL patients, SIRT1 and p53 expression were significantly associated with shorter overall survival (OS) by univariate analysis (P=0.001 and P=0.011, respectively). SIRT1 was also an independent prognostic factor by multivariate analysis (P=0.01). According to the expression patterns of CD10, bcl6, and MUM1, germinal center B cell (GCB) types were represented in 38 cases (37%) and non-GCB types were represented in 66 cases (63%). In the GCB type, only p53 expression was associated with a significantly shorter OS (P=0.032). In the non-GCB type, expression of SIRT1 correlated with shorter OS by univariate analyses (P=0.005) and multivariate analyses (P=0.049). In conclusion, we showed that SIRT1 expression is a clinically significant prognostic indicator for DLBCL patients.

Increased expression of epidermal growth factor receptor and betacellulin during the early stage of gastric ulcer healing.

Epidermal growth factor receptor (EGFR) is important for the proliferation and differentiation of gastric mucosal cells. Betacellulin (BTC) is a novel ligand for EGFR Since their role is unclear in the ulcer healing process, we investigated their expression. Gastric ulcers in 30 Sprague-Dawley rats were induced by acetic acid. RT-PCR and Western blotting were performed to detect EGFR and BTC. Immunohistochemical studies were performed to detect EGFR, BTC and proliferating cell nuclear antigen (PCNA). The expression of EGFR and the BTC gene was significantly increased at 12 h, 24 h and 3 days after ulcer induction (P<0.05). The expression of EGFR and BTC protein was significantly increased at 24 h and 3 days and at 12 h, 24 h and 3 days after ulcer induction, respectively (P<0.05). The phosphorylation of EGFR also increased significantly and reached a maximum 24 h after ulcer induction (P<0.05). Immunostaining for EGFR and BTC was observed in numerous epithelial cells from the ulcer margin and ulcer bed, and corresponded to the localization of PCNA. To conclude, there was an increase in EGFR and BTC expression in the early stages of ulcer healing, localized in the epithelial cells of the ulcer margins and regenerating glands with proliferating activity. BTC/EGFR may play an important role in the early stages of ulcer healing.

Overexpression of discoidin domain receptor 1 increases the migration and invasion of hepatocellular carcinoma cells in association with matrix metalloproteinase.

The discoidin domain receptor (DDR) is a class of receptor tyrosine kinases that binds to several collagens. DDR1 is widely expressed in fast-growing invasive tumors of the breast, ovary, esophagus, brain and lung. However, there is little information on the expression of DDR1 in hepatocellular carcinoma (HCC) or its function in migration and invasion. Western blot analysis was performed to determine if four HCC cell lines (HLE, Huh-7, HepG2 and SH-J1) express DDR1. The HLE and Huh-7 cell lines were transfected with two isoforms of DDR1, DDR1a and DDR1b. Immunoprecipitation for DDR1 was then performed. Migration and invasion assays were carried out and the number of migrating cells was counted in 6 randomly selected fields per well under an optical microscope. Zymography was used to determine the level of the matrix metalloproteinase (MMP)-2 and -9 expression. DDR1 was expressed in all four cell lines. In the migration assay, the number of migrating cells was significantly higher in the DDR1a- or DDR1b-overexpressing HLE and Huh-7 cells, particularly after collagen type I stimulation (P<0.001). Collagen type I stimulation activated DDR1. In the invasion assay, there was a significantly higher number of invading cells in the DDR1a- or DDR1b-overexpressing HLE cells and DDR1a-overexpressing Huh-7 cells than in the control (P<0.01). The DDR1a- and DDR1b-overexpressing HLE cells showed a remarkable increase in the MMP-9 and -2 expression, particularly the active MMP-2. The DDR1a- and DDR1b-overexpressing Huh-7 cells showed a slight increase in the MMP-9 and -2 expression. The increased invasiveness of the HCC may be associated with the overexpression of either DDR1a or DDR1b mediated by MMP-2 and -9. Although this study provided one possible mechanism for the invasion of HCC cells, more studies are needed to understand the signal through which DDR1a and DDR1b act in invasion.

Expression of the serum response factor in hepatocellular carcinoma: implications for epithelial-mesenchymal transition.

The acquisition of a migratory and invasive phenotype by cells of epithelial origin is associated with a gain of mesenchymal characteristics concomitant with a loss of the epithelial phenotype, a phenomenon referred to as epithelial-mesenchymal transition (EMT). Vimentin, a cytoplasmic intermediate filament, is characteristic of mesenchymal cells and is usually not expressed in epithelial cells. Increased expression of vimentin in carcinomas correlates with parameters of malignant potential such as tumor grade and tumor invasion. Serum response factor (SRF) regulates transcription of immediate early genes and triggers proliferation, migration and differentiation in several types of cells. However, the role of SRF in hepatocellular carcinoma (HCC) has not been explored. The aims of this study were to evaluate the expression of SRF and to assess a functional role of SRF in HCC. First, we examined the expression of SRF in 55 human specimens of HCC and four different HCC cell lines, including a sarcomatoid HCC cell line. We also examined the role of SRF in HCC by transfection of an SRF expression plasmid into a HCC cell line. SRF was expressed in 13 of 55 cases of HCC. SRF was predominantly expressed in HCC cells, with intense labeling in the nucleus. No staining was observed in hepatocytes of normal and cirrhotic liver outside the tumor. SRF was significantly up-regulated in high grade HCC, especially in sarcomatoid HCC. Overexpression of SRF in hepatocellular carcinoma cells accelerates migration and invasion with subsequent acquisition of mesenchymal phenotype by expression of a mesenchymal marker (vimentin) and activation of immediate early genes. We propose for the first time that the expression of SRF in HCC cells associated with EMT may play an important role in HCC progression. Thus, functional antagonism of SRF will provide an additional therapeutic approach by controlling tumor cell invasion and metastasis.

[Expression of caveolin in hepatocellular carcinoma: association with unpaired artery formation and radiologic findings].

BACKGROUND/AIMS: Hepatocellular carcinoma (HCC) is becoming one of the common malignant tumors worldwide, and it is characterized by its high vascularity. Caveolin is the major structural protein in caveolae, which are small omega-shaped invaginations within the plasma membrane. Caveolin has been implicated in mitogenic signaling, oncogenesis and angiogenesis. The expression of caveolin-1 and -2 in HCC and its potential relationship with angiogenesis has not been examined. METHODS: Paraffin sections of 35 HCC specimens were immunostained with caveolin-1, caveolin-2, alpha-smooth muscle actin, and CD34 antibodies. In addition, the expression of caveolin-1 and -2 mRNA in HCC was examined. The relationship between the radiological findings and the number of unpaired arteries and microvessel density (MVD) was also investigated. RESULTS: Caveolin-1 and -2 were expressed in the sinusoidal endothelial cells in 20 out of 35, and 18 out of 35 HCC specimens, respectively. Caveolin-1 and -2 were also expressed in the smooth muscle cells of the unpaired arteries in 26 out of 35, and 18 out of 35 HCC specimens, respectively. Increased expression of caveolin-1 and -2 mRNA was detected in 26.7% and 33.3% of the tumor specimens, respectively, compared with the corresponding non-tumorous adjacent liver tissues. There was a significant correlation between expression of caveolin-1, -2 in the smooth muscle cells of unpaired arteries and the number of unpaired arteries. The number of unpaired arteries in HCCs was found to be associated with the degree of contrast enhancement in the arterial phase imaging. However, it did not correlate with the degree of MVD. CONCLUSIONS: These findings suggest that the expression of caveolin-1, -2 is associated with the formation of unpaired arteries in HCC. In addition, there is a correlation between the degree of contrast enhancement of the HCC in the arterial phase image and the number of unpaired arteries.

A peroxisome proliferator-activated receptor gamma antagonist induces vimentin cleavage and inhibits invasion in high-grade hepatocellular carcinoma.

Increased expression of vimentin in carcinomas correlates with parameters of malignant potential such as tumor grade and tumor metastasis. Peroxisome proliferator-activated receptor gamma (PPARgamma) has been intensively evaluated as a potential target for the inhibition of cell growth and metastasis in cancer cells. In the present study, we examined whether PPARgamma is a possible target molecule for the prevention of cell growth and invasion by treatment with agonists (troglitazone, rosiglitazone) and antagonists (T0070907, GW9662) in four different hepatocellular carcinoma (HCC) cell lines. We also evaluated the effects of the PPARgamma agonists and antagonists on tumor cell migration and invasion. The expression level of PPARgamma protein was higher in the sarcomatoid SH-J1 and poorly differentiated HLE cell lines than that in the well-differentiated HCC cell lines (HepG2 and Huh-7). Expression of vimentin was high in the SH-J1 HCC cell line and minimally detected in the HLE cell line. Treatment with low doses of the PPARgamma antagonists inhibited cell growth and colony formation of all four of the HCC cell lines. Vimentin in the high-grade HCC cells was cleaved by the treatment with the PPARgamma antagonists. Furthermore, treatment with the PPARgamma antagonists also strongly inhibited migration and invasion of the SH-J1 and HLE cells. However, treatment with low doses of the agonists had no effect on vimentin expression, migration, and invasion of the high-grade HCC cells but cell growth was inhibited by treatment with high concentrations of the agonists. Our results indicate that treatment with a PPARgamma antagonist may prevent cell growth and invasion of high-grade HCC cells. Our findings also suggest that PPARgamma antagonists inhibit cell growth and invasion through vimentin disarrangement in high-grade HCC.

Expression of betacellulin and epidermal growth factor receptor in hepatocellular carcinoma: implications for angiogenesis.

Hepatocellular carcinoma (HCC) is becoming one of the common malignant tumors worldwide and is characterized by high vascularity. Angiogenesis (formation of new microvessels) is critical for growth and progression of various human solid tumors. Betacellulin (BTC) is a member of the epidermal growth factor (EGF) family, and its signal action is mediated through EGF receptors (EGFR). In this study, to understand the role of BTC in relation to EGFR in HCC, we examined localization, expression, and involvement in angiogenesis of BTC and EGFR. The results revealed that expression of BTC, EGFR, and tumor growth factor-alpha messenger RNA in HCC was increased by 80%, 60%, and 40%, respectively, as compared with those in the nontumorous tissues. Increased expression of BTC protein was observed in 31 (61%) of 51 HCC specimens, and the level of tumor growth factor-alpha protein was higher in 17 (33%) of 51 HCC specimens than in nonmalignant hepatocytes. Betacellulin was predominantly expressed in HCC cells, whereas EGFR was observed in sinusoidal endothelial cells of HCC in 25 tumors (49%). Betacellulin was secreted in all 4 examined HCC cell lines. The HCC specimens showing positive EGFR expression in tumor endothelial cells had a significantly higher microvessel density than those without EGFR expression (P < .005). A strong correlation was found between BTC expression in cancer cells and EGFR expression in tumor endothelial cells (P < .001). These findings suggest that overexpression of BTC by HCC cells and EGFR by tumor endothelial cells enhance vascularity in a paracrine manner.

Vascular endothelial growth factor increases the intracellular magnesium.

Vascular endothelial growth factor (VEGF) is one of the key players in the process of angiogenesis. However, its underlying mechanism remains unclear. Mg2+ is the most abundant intracellular divalent cation in the body and plays critical roles in many cell functions. We investigated the effect of VEGF on intracellular Mg2+ in human umbilical vein endothelial cells (HUVECs). VEGF-A165 increased the intracellular Mg2+ concentration ([Mg2+]i) in a dose-dependent manner, with or without extracellular Mg2+, and the increase of [Mg2+]i was blocked by pretreatment with SU1498, tyrosine kinase inhibitors (tyrphostin A-23 and genistein), phosphatidylinositol 3-kinase (PI3K) inhibitors (wortmannin and LY294002) or phospholipase Cgamma (PLCgamma) inhibitor (U73122). In contrast, mitogen-activated protein kinase inhibitors (SB202190 and PD98059) had no effect on the VEGF-induced [Mg2+]i increase. These results suggest that VEGF-A165 increases the [Mg2+]i from the intracellular Mg2+ stores through the tyrosine kinase/PI3K/PLCgamma-dependent signaling pathways.

Direct block of cloned hKv1.5 channel by cytochalasins, actin-disrupting agents.

The action of cytochalasins, actin-disrupting agents on human Kv1.5 channel (hKv1.5) stably expressed in Ltk(-) cells was investigated using the whole cell patch-clamp technique. Cytochalasin B inhibited hKv1.5 currents rapidly and reversibly at +60 mV in a concentration-dependent manner with an IC(50) of 4.2 microM. Cytochalasin A, which has a structure very similar to cytochalasin B, inhibited hKv1.5 (IC(50) of 1.4 microM at +60 mV). Pretreatment with other actin filament disruptors cytochalasin D and cytochalasin J, and an actin filament stabilizing agent phalloidin had no effect on the cytochalasin B-induced inhibition of hKv1.5 currents. Cytochalasin B accelerated the decay rate of inactivation for the hKv1.5 currents. Cytochalasin B-induced inhibition of the hKv1.5 channels was voltage dependent with a steep increase over the voltage range of the channel's opening. However, the inhibition exhibited voltage independence over the voltage range in which channels are fully activated. Cytochalasin B produced no significant effect on the steady-state activation or inactivation curves. The rate constants for association and dissociation of cytochalasin B were 3.7 microM/s and 7.5 s(-1), respectively. Cytochalasin B produced a use-dependent inhibition of hKv1.5 current that was consistent with the slow recovery from inactivation in the presence of the drug. Cytochalasin B (10 microM) also inhibited an ultrarapid delayed rectifier K(+) current (I(K,ur)) in human atrial myocytes. These results indicate that cytochalasin B primarily blocks activated hKv1.5 channels and endogenous I(K,ur) in a cytoskeleton-independent manner as an open-channel blocker.

Co-expression of cox-2, C-met and beta-catenin in cells forming invasive front of gallbladder cancer.

PURPOSE: Gallbladder cancer is a malignancy with poor prognosis, predominantly resulting from invasion and metastasis. Our previous studies have demonstrated that prostaglandin E(2) (PGE(2)), generated by cyclooxygenase 2 (Cox-2), transactivates epidermal growth factor receptor (EGFR), c-Met and beta-catenin; thus, enhancing colon cancer cell growth and invasiveness in vitro. To determine whether these findings are applicable to clinical conditions, we examined the expression and cellular localization/co-localization of Cox-2, c-Met, beta-catenin, EGFR and c-erbB2 in gallbladder cancer. MATERIALS AND METHODS: Thirty-five specimens of invasive gallbladder cancer, 8 in situ carcinoma and 7 adenoma specimens were immunostained with specific antibodies against Cox-2, c-Met, beta-catenin, EGFR and c-erbB2. The cellular distribution, localization and colocalization were examined, and the signal intensities quantified in: a) the central area of gallbladder cancer and b) cancer cells forming the invasive front. RESULTS: Cox-2, c-Met, beta-catenin, c-erbB2 and EGFR were over-expressed in 80, 74, 71, 62 and 11% of invasive gallbladder cancers, respectively. beta-catenin was expressed in 80% of non-malignant specimens, exclusively in the cell membrane, while the cancer specimens showed cytoplasmic and/or nuclear staining. Significantly higher Cox-2, c-Met and beta-catenin expressions were present in cancer cells of the invasive front than in the tumor central areas (p<0.001), and these expressions were significantly (p=0.01) associated with the invasion depth. Co-expressions of Cox-2, c-Met, beta-catenin and c-erbB2 were present in 42% of the specimens in cancer cells forming the invasive front. CONCLUSION: The overexpressions, and often co-localizations, of Cox-2, c-Met and beta-catenin in cancer cells forming the invasive front indicate their local interactions and important roles in invasion.