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Parafibromin is a protein encoded by the oncosuppressor CDC73 gene, whose mutation results in hyperparathyroidism-jaw tumor syndrome (HPT-JT) and parathyroid carcinoma. Down-regulation of parafibromin is linked to lung, gastric, colorectal, and ovarian cancer tumorigenesis. Parafibromin expression was detected by RT-PCR, bioinformatics analysis, Western blot, and immunohistochemistry; and compared with clinicopathological characteristics of breast cancer. CDC73-related genes and pathways were analyzed using bioinformatics analysis. Parafibromin expression was increased in breast cancer compared to normal tissues at both mRNA and protein levels (p0.05). Among triple-negative breast cancers, it was higher in basal-like 1 than basal-like 2 patients (p0.05) and mesenchymal than immunomodulatory patients (p0.05). CDC73 mRNA expression was positively correlated with white race, non-infiltrating immune cells, favorable luminal subtypes of PAM50, and prognosis of breast cancer patients (p0.05). The differential genes of CDC73 were classified into enzyme inhibitors, peptidase, and keratinization by KEGG (p0.05). Similarly, it was classified into ribosomes, TGF-β, oxidation phosphorylation, inositol phosphate metabolism, arachidonic acid metabolism, linoleic acid metabolism, ERBB, and VEGF signaling pathways by GSEA (p0.05). The positively-correlated genes of CDC73 were involved in cell mobility, response to interferon α, nuclear pore and basket, and histone methyltransferase. The negatively-correlated genes of CDC73 were involved in the mitochondrial respiratory chain, thermogenesis, and ribosomes. Parafibromin expression was higher in invasive ductal than lobular carcinoma (p0.05) and mucinous adenocarcinoma than others (p0.05). Parafibromin immunoreactivity as an independent factor was positively associated with an increased overall survival rate of breast cancer patients (p0.05). These findings suggest that up-regulation of parafibromin in breast cancer patients is closely linked to a favorable prognosis. It is involved in tumorigenesis and subsequent progression by regulating metabolism, ribosomes, and cytokines.

Large tumor suppressor gene 1 (LATS1) belongs to the PKA/PKG/PKC serine/threonine kinase subfamily of the Hippo signaling pathway and inactivates nuclear co-activators YAP1 and WWTR1 by phosphorylation. This study aimed to discern the clinicopathological and prognostic significances of LATS1 expression in breast cancer.We examined LATS1 expression in breast carcinogenesis and compared it with clinicopathological parameters and survival information of breast cancer patients using immunohistochemistry, western blotting, RT-PCR, and bioinformatics analysis.LATS1 expression was downregulated in breast cancer at both mRNA and protein levels (P0.05). LATS1 mRNA expression was negatively correlated with low ER and PR expression, aggressive subtypes (TNBC and HER2+ vs. luminal), and poor survival (P0.05). Its protein expression was negatively linked to patient age, T stage, N stage, M stage histological grade, PR status, and unfavorable prognosis (P0.05). There was a positive correlationship between nuclar and cytoplasmic LATS1 expression in breast cancer (P0.05).The downregulation of LATS1 expression plays a vital role in the carcinogenesis and progression of breast cancer. Thus, LATS1 loss was employed to indicate the aggressive behaviors and poor prognosis of breast cancer.

REIC (Reduced Expression in Immortalized Cells) gene is down-regulated in immortalized cells, compared with the normal parental counterparts. Its encoding protein could inhibit colony formation, tumor growth, and induce apoptosis. To investigate the roles of REIC expression in lung cancer, we examined REIC expression in lung cancer cells and tissues by RT-PCR or Western blot, and observed the effects of both recombinant REIC exposure and REIC overexpression on the aggressive phenotypes of lung cancer cells. It was found that the demethylation of REIC promoter by 5-Aza-dC could reserve its mRNA expression in lung cancer cells (P0.05). There was a lower REIC mRNA expression in lung cancer than that in matched normal tissue (P0.05). Recombinant REIC treatment enhanced the proliferation of lung cancer cells (P0.05), but versa for REIC overexpression (P0.05). Both recombinant REIC treatment and REIC overexpression induced apoptosis, and inhibited the migration and invasion of SQ-5 and KJ cells (P0.05). Immunohistochemically, there was a positive correlation between REIC and Caspase-3 expression in lung cancer (P0.05). According to Kaplan-Meier plotter, REIC mRNA overexpression was found to positively correlate with overall, progression-free and post- progression survival rates of lung cancer patients (P0.05), even stratified by sex, histological subtyping, grading, TNM staging, chemotherapy, radiotherapy, or smoking. These findings suggested that the down-regulated REIC expression might be involved in lung carcinogenesis due to its promoter methylation. Both recombinant REIC exposure and REIC overexpression might reverse the aggressive phenotypes of lung cancer cells. REIC may be employed as a potential target of gene therapy for lung cancer.

Bcl-2-associated athanogene 3 (Bag-3) belongs to a member of the Hsc70 binding co-chaperone Bag-family proteins and has critical roles in protein homeostasis, cell survival, actin organization, cell adhesion, cell motility and tumor metastasis. To clarify the role of Bag-3 in colorectal carcinogenesis and subsequent development, its expression was examined by immunohistochemistry (IHC) and in situ hybridization (ISH) on tissue microarrays containing colorectal carcinomas, adenomas, non-neoplastic mucosa (NNM) and metastatic carcinomas in lymph node and liver. Colorectal carcinoma tissue and cell lines were studied for Bag-3 expression by RT-PCR, Western blot and immunofluorescence. The results demonstrated that Bag3 was distinctly expressed in Colo201, Colo205, DLD-1, HCT-15, HCT-116, HT-29, KM-12, SW480, SW620, and WiDr at both mRNA and protein levels. Carcinoma showed stronger Bag-3 expression than adjacent NNM by IHC and Western blot (P0.05), while its mRNA had the opposite by real-time PCR and ISH (P0.05). Metastatic carcinoma more frequently expressed Bag-3 mRNA in lymph node and liver than in primary carcinoma (P0.05). Immunohistochemically, Bag-3 expression was seen to gradually decrease from carcinoma, adenoma to NNM (P0.05). There was a positive correlation between Bag-3 expression and TNM staging and GRP94 expression (P0.05), but no relationship to patient age or sex, tumor size, depth of invasion, lymphatic or venous invasion, lymph node metastasis, differentiation or prognosis of colorectal carcinomas (P0.05). Our study indicated that aberrant Bag-3 expression might be involved in colorectal adenoma-adenocarcinoma sequence and subsequent progression.

Parafibromin is a protein encoded by the hyperparathyroidism 2 oncosuppressor gene and its down-regulated expression is involved in the pathogenesis of parathyroid, gastric and colorectal carcinomas. To clarify the roles of parafibromin expression in lung carcinomas, it was examined by immunohistochemistry and in situ hybridization on tissue microarray containing lung carcinomas (n=144) and normal lung tissue (n=20), with a comparison to clinicopathological parameters of carcinomas. Lung carcinoma cell lines and tissues were studied for parafibromin expression by Western blot and RT-PCR. Down-regulated expression of parafibromin mRNA was found in lung carcinoma in comparison with matched normal tissue (p0.05). Parafibromin protein was found in the cilia and nuclei of pseudo-stratified columnar epithelium, and the nuclei of lung carcinoma. According to immunostaining and in situ hybridization, there was no difference in parafibromin expression between histological subtypes of lung carcinoma (p0.05). The Kaplan-Meier method indicated that nuclear parafibromin expression was positively correlated with adenocarcinoma patients (p0.05). Down-regulated parafibromin mRNA expression might play an important role in lung carcinogenesis, but not in its histogenesis. Strong parafibromin expression in cilia of the pseudo-stratified columnar epithelium indicated its possible involvement in cell mobility. Parafibromin expression could be employed to indicate the favorable prognosis of patients with adenocarcinoma.

Glucose-related proteins (GRPs) are ubiquitously expressed in the endoplasmic reticulum and assist in protein folding and assembly, consequently considered to be molecular chaperones. GRP78 and GRP94 expression was induced by glucose starvation and up-regulated in samples taken from several different malignant tissues. To clarify the roles of both molecules in tumorigenesis and progression of colorectal carcinomas, immunohistochemistry (IHC) was performed on tissue microarrays containing colorectal carcinomas, adenomas and the non-neoplastic mucosa (NNM) using antibodies against GRP78 and GRP94. Their expression was correlated with the clinicopathological parameters of carcinomas. Both proteins were also studied in colorectal carcinoma cell lines (DLD-1, HCT-15, SW480 and WiDr) by IHC and Western blot. There was a gradually increased GRP78 expression from colorectal NNMs, carcinomas, to low-grade and high-grade adenomas (P0.05), while up-regulated GRP94 expression from NNM, low-grade adenoma, high-grade adenoma, to carcinoma (P0.05). The expression was similar in all the carcinoma cell lines. GRP78 expression was negatively correlated with lymphatic invasion or low GRP94 expression of the carcinomas (P0.05), while there was no correlation of GRP94 expression with other parameters of carcinomas (P0.05). Multivariate analysis showed that venous invasion, lymph node metastasis and UICC staging (P0.05), but not age, sex, tumor size, differentiation, depth of invasion, lymphatic invasion, GRP78 and GRP94 expression (P0.05), were independent prognostic factors for carcinomas. It is suggested that up-regulated expression of GRP78 and GRP94 could possibly be involved in the pathogenesis of colorectal carcinomas.

Japan is a high-risk region for gastric carcinoma with a comparatively early stage and favorable prognosis. To clarify the pathobiological behaviors and prognosis of Japanese gastric adenocarcinoma, we analyzed the clinicopathological characteristics of different WHO subtypes of carcinomas. The expression of ki-67, CPP32, p53, FHIT, maspin, parafibromin, GRP78, GRP94, EMMPRIN, VEGF, P-GSK3beta-ser9, fascin, cortactin, Arp2, Arp3 MUC-2, MUC-5AC and MUC-6 was examined using immunohistochemistry and tissue microarrays. The majority of cases were well-, poorly-, or moderately-differentiated subtype, whereas the minority were papillary or signet ring cell carcinoma (SRC). Patients with poorly-differentiated or SRC carcinoma were predominantly young and female. Poorly-differentiated and mucinous carcinomas were larger, with deeper invasion, more venous or lymphatic invasion, frequent lymph node involvement and peritoneal dissemination, or higher staging. The SRC group exhibited weaker expression of ki-67, CPP32, p53, parafibromin, GRP78, GRP94, P-GSK3beta-ser9, VEGF or cortactin. The moderately-differentiated subtype exhibited lower expression of FHIT and Arp3 positivity. The poorly-differentiated group showed weaker expression of CPP32, EMMPRIN, MUC-2, MUC-5AC, and MUC-6. Survival analysis indicated that the patients with poorly-differentiated or mucinous subtypes had a lower cumulative survival rate than those with papillary, well-, moderately-differentiated, or SRC carcinomas (P0.05). The age, invasive depth, lymphatic invasion, peritoneal dissemination, and WHO classification were independent prognostic factors for carcinoma patients (P0.05). It was suggested that poorly-differentiated and mucinous subtypes are more aggressive and of unfavorable prognosis among Japanese gastric carcinomas. Lower levels of proliferation and apoptosis, as well as alterations in tumor suppressor genes, mucin production and ER stress protein played important roles in the pathogenesis of poorly-differentiated and SRC carcinomas.

To clarify the role of REG IV, a new member of the regenerating gene (REG) family, in tumorigenesis and progression of colorectal carcinoma (CRC), 320 CRC specimens, 123 corresponding adjacent non-cancerous mucosa (ANCMs), 46 corresponding non-adjacent non-cancerous mucosa (NANCMs) and 86 adenomas were investigated immunohistochemically to compare REG IV expression with clinicopathological features. In addition, double immunofluorescence labeling was performed to analyze the localization of REG IV and the intestinal mucin, MUC2. The expression of REG IV in CRCs was significantly lower than in NANCMs, ANCMs or adenomas, and inversely correlated with poor differentiation and venous invasion. In cases of ANCM, REG IV expression was positively correlated with the depth of invasion, lymph node metastasis and Duke's staging of corresponding cases. The expression of REG IV in CRC was significantly linked to that of MUC2 and the EGFR phosphorylated on Tyr1068, but not to that of MUC5AC, EGFR, Akt, or Akt phosphorylated on Ser473 or Thr308. The double immunofluorescence revealed coexpression, but independent localization, of REG IV and MUC2 in NANCMs, ANCMs, adenomas and CRCs, except for mucinous carcinomas. Univariate analysis using the Kaplan-Meier method indicated no correlation between REG IV expression and the cumulative survival rate of CRC patients. In conclusion, REG IV expression was upregulated in ANCMs and adenomas, then decreased in CRCs. This indicated that REG IV overexpression may be an early event in CRC carcinogenesis. Its expression in CRCs was positively linked to MUC2 and phosphorylation of the EGFR on Tyr1068, suggesting that REG IV may be a useful marker for intestinal type mucinous carcinoma and a good candidate as a molecular therapeutic target for CRCs.