Ion of malignancies in various cell lines [11]. Abnormal levels of PKCa have been found in MedChemExpress 298690-60-5 transformed cell lines and human cancers [12]. Substantial evidence from gene knockout studies indicates that PKCa activity regulates cancer growth and progression. Selective targeting of PKCa thus has a potential therapeutic role in a wide variety of human cancers [13]. The specific role of PKCa in gastrointestinal tumors has not been well studied [14]. Among the PKC family, PKCa is the most abundant 
isoform in gastric epithelia, and might play an important role in the carcinogenesis and metastasis of gastric cancers [10]. Furthermore, PKCa is known to play a critical role in cancer cell proliferation and in maintaining the transformed phenotype and tumorigenic capacity of gastric cancer cells [10,14]. Our previous study using quantitative real-time PCR tests demonstrated that in gastric carcinoma, 1326631 PKCa mRNA overexpression was correlated with distant metastasis, and might be an independent prognostic marker [15]. However, the expression of PKCa protein in gastric carcinoma and its clinicopathological correlations have not been investigated. Our study thus evaluated the expression of PKCa protein in gastric carcinoma using immunohistochemical method. The aims of this study were to assess the expression of PKCa protein in gastric carcinoma, and to correlate it with other clinicopathological parameters. The prognostic significance of PKCa protein overexpression in gastric carcinoma was also investigated.Quantitative Real-Time PCR TestAt first quantitative real-time PCR test was applied to test and compare the mRNA expression of PKCa in tumorous and nontumorous tissues of gastric carcinoma in a small scale. Ten tumor and non-tumor pairs of gastric tissues were randomly selected from the Tumor and Serum Bank of Chi-Mei Medical Center (Tainan, Taiwan). All samples were collected from the specimens via radical gastrectomy. The non-tumor part was taken from the grossly normal gastric mucosa away from the tumor. All tissues were frozen in liquid nitrogen within 20 min and kept at ?0uC until use. The procedure of quantitative real-time PCR test was performed according to previous study [15].Immunohistochemical StudySections of 5 mm thickness were taken from formalin-fixed paraffin-embedded blocks. The procedure of immunohistochemical study was performed according to previous study [15]. Deparaffinized sections were incubated in pH 6.0 citrate buffer for 40 min at 95uC on a hotplate to retrieve the antigens. Endogenous peroxidase was blocked by 3 hydrogen peroxide for 5 min. The sections were subsequently incubated with antibody against PKCa (Santa Cruz Biotechnology Inc., Santa Cruz, CA, SC-8393) for 30 min at room temperature at a dilution of 1:100 using DAKO primary antibody diluent. To ML 281 detect immunoreactivity, the avidinbiotin-complex method was applied according to the manufacturer’s instructions. A sensitive Dako EnVision kit (Dako North America Inc., Carpinteria, CA) was used as the detection system. After incubation with secondary antibody (DAKO EnVision) for 30 min at room temperature, followed by 
diaminobenzidine for 8 min, sections were counterstained with Mayer’s hematoxylin. Normal human distal renal tubules were used as a positive control. The negative control was made by omitting the primary antibody and incubation with PBS. The PKCa immunoreactivity was evaluated independently by two pathologists (CL Fang and SE Lin). As in previous studies.Ion of malignancies in various cell lines [11]. Abnormal levels of PKCa have been found in transformed cell lines and human cancers [12]. Substantial evidence from gene knockout studies indicates that PKCa activity regulates cancer growth and progression. Selective targeting of PKCa thus has a potential therapeutic role in a wide variety of human cancers [13]. The specific role of PKCa in gastrointestinal tumors has not been well studied [14]. Among the PKC family, PKCa is the most abundant isoform in gastric epithelia, and might play an important role in the carcinogenesis and metastasis of gastric cancers [10]. Furthermore, PKCa is known to play a critical role in cancer cell proliferation and in maintaining the transformed phenotype and tumorigenic capacity of gastric cancer cells [10,14]. Our previous study using quantitative real-time PCR tests demonstrated that in gastric carcinoma, 1326631 PKCa mRNA overexpression was correlated with distant metastasis, and might be an independent prognostic marker [15]. However, the expression of PKCa protein in gastric carcinoma and its clinicopathological correlations have not been investigated. Our study thus evaluated the expression of PKCa protein in gastric carcinoma using immunohistochemical method. The aims of this study were to assess the expression of PKCa protein in gastric carcinoma, and to correlate it with other clinicopathological parameters. The prognostic significance of PKCa protein overexpression in gastric carcinoma was also investigated.Quantitative Real-Time PCR TestAt first quantitative real-time PCR test was applied to test and compare the mRNA expression of PKCa in tumorous and nontumorous tissues of gastric carcinoma in a small scale. Ten tumor and non-tumor pairs of gastric tissues were randomly selected from the Tumor and Serum Bank of Chi-Mei Medical Center (Tainan, Taiwan). All samples were collected from the specimens via radical gastrectomy. The non-tumor part was taken from the grossly normal gastric mucosa away from the tumor. All tissues were frozen in liquid nitrogen within 20 min and kept at ?0uC until use. The procedure of quantitative real-time PCR test was performed according to previous study [15].Immunohistochemical StudySections of 5 mm thickness were taken from formalin-fixed paraffin-embedded blocks. The procedure of immunohistochemical study was performed according to previous study [15]. Deparaffinized sections were incubated in pH 6.0 citrate buffer for 40 min at 95uC on a hotplate to retrieve the antigens. Endogenous peroxidase was blocked by 3 hydrogen peroxide for 5 min. The sections were subsequently incubated with antibody against PKCa (Santa Cruz Biotechnology Inc., Santa Cruz, CA, SC-8393) for 30 min at room temperature at a dilution of 1:100 using DAKO primary antibody diluent. To detect immunoreactivity, the avidinbiotin-complex method was applied according to the manufacturer’s instructions. A sensitive Dako EnVision kit (Dako North America Inc., Carpinteria, CA) was used as the detection system. After incubation with secondary antibody (DAKO EnVision) for 30 min at room temperature, followed by diaminobenzidine for 8 min, sections were counterstained with Mayer’s hematoxylin. Normal human distal renal tubules were used as a positive control. The negative control was made by omitting the primary antibody and incubation with PBS. The PKCa immunoreactivity was evaluated independently by two pathologists (CL Fang and SE Lin). As in previous studies.