Prediction and identification of HLA-A*0201-restricted epitopes from cancer testis antigen CT23.

Cancer-testis antigen CT23 is a class of tumor-associated antigens (TAA) characterized by restricted expression in male germ cells and a variety of tumor tissues. Numerous studies have shown that CT23 is closely related to tumor cell viability, proliferation, metastasis and invasion. CT23 is immunogenic and can cause specific immune response in tumor patients. Therefore, it is considered to be one of the best target antigens for designing therapeutic tumor vaccines and T-cell-mediated tumor immunotherapy. In this study, we initially obtained seven HLA-A*0201-restricted CT23 epitope candidate peptides through the T cell epitope prediction program. Subsequently, a T2 cell binding assay revealed the potential binding of all candidate peptides with HLA-A2 molecules. Notably, peptide P7 (ALLVLCYSI) exhibited the highest affinity, as evidenced by a fluorescence index (FI) of 2.19. Dendritic cells (DCs) loaded with CT23 candidate peptide can stimulate CD8+T cell activation and proliferation, and compared with other candidate peptides, candidate peptide P7 is superior. The cytotoxic T lymphocytes (CTLs) stimulated by the peptide P7 had killing effect on tumor cells (HLA-A*0201+, CT23+), but no killing effect on tumor cells (HLA-A*0201-, CT23+). The CTLs induced by the peptide P7 also had a specific killing effect on T2 cells bearing the peptide P7. In summary, our findings suggest that the CT23 peptide P7 (ALLVLCYSI) can induce immune responses and holds potential for tumor-specific CTL therapy.

High Expression of Fibronectin 1 Predicts a Poor Prognosis in Glioblastoma.

OBJECTIVE: Glioblastoma multiforme (GBM), the most malignant intracranial neoplasm, is associated with a high mortality and recurrence rate due to the aggressive nature and heterogeneity of the tumor. Some of the molecular markers involved in the tumorigenesis of GBM are essential in prognosis, diagnosis, and treatment. Due to the limitations of therapeutic effects, this study aims to explore novel biomarkers with prognostic value and to provide new insights into therapeutic targets. METHODS: The expression profile of mRNAs in GBM was detected by RNA-sequencing, and differentially expressed genes were identified by integrating the data from RNA-seq results and the GEPIA2 database. Of the total 40 hub genes, FN1, P4HB, and PPIB showed prognostic significance based on both GEPIA2 and CGGA databases. The validation of FN1, P4HB, and PPIB expression by qPCR and correlation analysis with clinicopathological features were performed in 41 GBM tissues from our institution. RESULTS: Kaplan-Meier analysis revealed that FN1 and P4HB expressions levels were related to the overall survival (OS) of GBM patients (P<0.05). Multivariate analysis showed that FN1 overexpression (HR=9.199, P=0.002) was an independent and unfavorable prognostic factor for GBM patients. The median survival time was 8.5 months and 21 months for high and low expressions of FN1, respectively. CONCLUSION: It was suggested that FN1 could be an ideal target for prognosis and a potential therapeutic target in GBM.

Combined treatment with epigenetic agents enhances anti-tumor activity of MAGE-D4 peptide-specific T cells by upregulating the MAGE-D4 expression in glioma.

Objective: The study evaluated the efficacy of combined epigenetic drugs of decitabine (DAC), valproic acid (VPA), and trichostatin A (TSA) on immunotherapy against glioma. Methods: The expression and prognosis of MAGE-D4 in glioma were analyzed online, and the expression of MAGE-D4 and HLA-A2 in glioma induced by epigenetic drugs was detected by qRT-PCR, Western blot, and flow cytometry. The methylation status of the MAGE-D4 promoter was determined by pyrosequencing. An HLA-A2 restricted MAGE-D4 peptide was predicted and synthesized. An affinity assay and a peptide/HLA complex stability assay were performed to determine the affinity between peptide and HLA. CCK8 assay, CFSE assay, ELISA and ELISPOT were performed to detect the function of MAGE-D4 peptide-specific T cells. Flow cytometry, ELISA, and cytotoxicity assays were used to detect the cytotoxicity effect of MAGE-D4 peptide-specific T cells combined with epigenetic drugs against glioma in vitro. Finally, the glioma-loaded mouse model was applied to test the inhibitory effect of specific T cells on gliomas in vivo. Results: MAGE-D4 was highly expressed in glioma and correlated with poor prognosis. Glioma cells could be induced to express MAGE-D4 and HLA-A2 by epigenetic drugs. MAGE-D4-associated peptides were found that induce DCs to stimulate the highest T-cell activities of proliferation, IL-2 excretion, and IFN-γ secretion. MAGE-D4 peptide-specific T cells treated with TSA only or combining TSA and DAC had the most cytotoxicity effect, and its cytotoxicity effect on glioma cells decreased significantly after HLA blocking. In vivo experiments also confirmed that MAGE-D4-specific T cells inhibit TSA-treated glioma. Conclusion: MAGE-D4 is highly expressed in glioma and correlated with the prognosis of glioma. The novel MAGE-D4 peptide identified was capable of inducing MAGE-D4-specific T cells that can effectively inhibit glioma growth, and the epigenetic drug application can enhance this inhibition.

FMR1NB Involved in Glioma Tumorigenesis Is a Promising Target for Prognosis and Therapy.

OBJECTIVE: Cancer/testis antigen FMR1NB is aberrantly expressed in various types of cancer, but not in normal tissues except for testis. This study aimed to investigate the expression and functional role of FMR1NB in glioma. METHODS: The expression of FMR1NB mRNA and protein was determined using RT-PCR and immunohistochemistry, respectively, in glioma specimens from 83 patients at follow-up. The effects of siRNA-mediated FMR1NB silencing on malignant biological behaviors were evaluated in glioma cell lines A172 and U251. RESULTS: FMR1NB mRNA and protein expression was detected in 58.8% (77/131) and 46.34% (57/123) of glioma tissues, respectively. FMR1NB protein was positively correlated with World Health Organization grade and found to be an independent prognostic marker for poor outcome. Knockdown of FMR1NB induced apoptosis and suppressed proliferation, adhesion, migration, and invasion by modulating the expression of cyclin A, CDK2, caspase-3, E-cadherin, and N-cadherin in A172 and U251 cells. CONCLUSION: Our findings suggest that FMR1NB contributes to the tumorigenesis of glioma cells and may represent a potential prognostic biomarker and an attractive therapeutic target in glioma.

Microrna-1224-5p Is a Potential Prognostic and Therapeutic Biomarker in Glioblastoma: Integrating Bioinformatics and Clinical Analyses.

OBJECTIVE: Glioblastoma (GBM) is the most common, invasive, and malignant primary brain tumor with a poor prognosis and high recurrence rate. It's known that some microRNAs (miRNAs) which are associated with tumorigenesis and progression can be considered as prognostic and therapeutic targets in tumors including GBM. This study aims to highlight the potential role of the core miRNAs in GBM and their potential use as a prognostic and therapeutic biomarker. METHODS: Differentially expressed miRNAs (DEmiRNAs) were identified in GBM by integrating miRNA-sequencing results and a GBM microarray dataset from the Gene Expression Omnibus (GEO) database through bioinformatics tools. The dysregulated miRNAs were identified by survival analysis through Chinese Glioma Genome Atlas (CGGA). Target genes of the dysregulated miRNAs were predicted on MiRWalk and miRTarBase database. TAM2.0 database, Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways analysis were used to analyze the function of the dysregulated miRNAs. Subsequently, protein-protein interaction (PPI) network analysis was used to identify the top 20 hub targets of the up-regulated and down-regulated miRNAs, respectively. Then, core miRNAs in GBM were identified by constructing dysregulated miRNA-differentially expressed hub gene networks. Validation of the core miRNAs expression was detected in 41 GBM tissues compared to 8 normal brain tissues. Furthermore, the potential biomarkers were identified by clinical correlation analysis and survival analysis. RESULTS: Totally, 68 intersecting DEmiRNAs were identified, 40 of which were upregulated and the other 28 miRNAs were downregulated. Two upregulated and 4 downregulated miRNAs showed prognostic significance. Most differentially expressed hub genes were regulated by the miR-28-5p and miR-1224-5p, which were respectively upregulated and downregulated in GBM. The correlation between miR-1224-5p level and recurrence was statistically significant (P=0.011). Survival analysis showed that high miR-28-5p level and high miR-1224-5p level were both associated with better prognosis. Moreover, high miR-1224-5p level was an independent prognosis factor for GBM patients according to the cox regression analysis. CONCLUSION: MiRNA-1224-5p could be a potential target for the prognosis and treatment in GBM.

Combined treatment with epigenetic agents enhances anti-tumor activity of T cells by upregulating the ACRBP expression in hepatocellular carcinoma.

OBJECTIVE: To evaluate the efficacy of combined epigenetic drugs of decitabine (DAC), valproic acid (VPA) and trichostatin A (TSA) on immunotherapy with a murine model of hepatocellular carcinoma (HCC). METHODS: Dendritic cells (DCs) transduced with recombinant lentivirus expressing a cancer-testis antigen, acrosin binding protein (ACRBP), are referred to as DC/ACRBP. CD8+ T cells were harvested from spleens of C57BL/6 mice and activated by DC/ACRBP. Cytotoxicity of DC/ACRBP-activated T cells was analyzed by cytotoxicity and murine xenograft assays. RESULTS: Cytotoxicity assay results revealed that DC/ACRBP-activated T cells exhibited the highest cytotoxicity against HCC cells pre-treated with triple drugs (DAC+VPA+TSA) compared with dual drugs (DAC+VPA and DAC+TSA) and single drug (DAC, VPA and TSA) respectively. Analyses of RT-PCR and immunoblotting demonstrated that the highest ACRBP expression of HCC cells was induced by the triple drugs compared with the single and dual drugs. These results indicated that DC/ACRBP-activated T cells might be ACRBP-specific lymphocytes, and the augmented cytotoxicity may be dependent on the upregulation of ACRBP expression. These assumptions were further confirmed by xenograft tumor assay. Tumor cells of mice administrated with the triple drugs exhibited increased ACRBP expression compared with those of mice without administration. As expected, DC/ACRBP-activated T cells adopted by mice injected with the triple drugs, compared with those adopted by mice without injection, remarkably impeded growth and facilitated apoptosis of tumor cells. CONCLUSION: These data suggested that combined treatment with DAC, VPA and TSA may enhance the anti-tumor efficacy of ACRBP-specific T cells by upregulating ACRBP expression in HCC.

A Review of miR-326 and Female Related Diseases.

MicroRNA (miRNA), a non-coding single-stranded RNA molecule with 20-23 nucleotides encoded by endogenous genes, plays an essential role in maintaining normal cell function and regulating cell proliferation, differentiation, apoptosis, autophagy, and cell metabolism. The imbalance between miRNA and genes can cause a series of diseases, including malignancies. miRNA-326 (miR-326) is extensively known for its core regulation of various biological processes. This review presents an overview of the highlights of miR-326 in female-related diseases. To understand the impact of miR-326 on female disorders, we search all published studies about miR-326 having a high incidence in female conditions, including cervical cancer, endometrial cancer, breast cancer, intrauterine adhesion, and multiple autoimmune diseases. We aim to learn about the mutual regulation mechanism between miR-326 and related genes and signaling pathways, as well as to elaborate on the value of miR-326 as a potential biomarker and therapeutic target of female diseases. Our results provide reliable evidence and new strategies for treating female tumors and autoimmune diseases.

Identification of Dysregulated microRNAs in Glioma Using RNA-sequencing.

Glioma is the most common malignant brain tumor in central nervous system. Despite advances in the treatment of glioma such as surgery and chemoradiotherapy, most patients are easy to relapse, resulting in adverse clinical outcomes. Hence, effective molecular-targeting treatment may be one of attractive strategies for glioma therapy. The dysregulated microRNAs (miRNAs), one of the candidates of therapeutic targets, are believed to play an important role in the progression of glioma. In this study, we aimed to examine the expression profile of miRNAs in glioma and provide a reference for glioma therapy. Firstly, expression profile of miRNAs in 5 normal brain tissues, 5 low-grade glioma (LGG) tissues and 5 glioblastoma (GBM) tissues was detected by RNA sequencing (RNA-seq). Next, the target genes of differentially expressed miRNAs (DEmiRNAs) were predicted and then GO enrichment and KEGG pathway analysis performed by bioinformatics. Finally, 10 miRNAs which were significantly up- or down-regulated both in GBM and LGG were validated by real-time quantitative PCR (qRT-PCR). RNA-seq results indicated a number of DEmiRNAs in glioma. There were 64 up-regulated miRNAs and 17 down-regulated miRNAs in LGG, and 181 up-regulated miRNAs and 124 down-regulated miRNAs in GBM, respectively. Bioinformatics analysis showed that the target genes of these DEmiRNAs were enriched in various biological processes and signaling pathways such as cell metabolic and developmental process. Selected DEmiRNAs were further confirmed by qRT-PCR. miRNA-10b-5p, miRNA-92b-3p and miRNA-455-5p were significantly up-regulated in both GBM and LGG; while miRNA-542-3p was significantly up-regulated in LGG; miRNA-184 and miRNA-206 were significantly down-regulated in both GBM and LGG; miRNA-766-5p and miRNA-1-3p were significantly down-regulated in GBM. The subject of our study demonstrated several dysregulated miRNAs may serve as a potential therapeutic target for glioma.

Cancer-testis Antigen OY-TES-1 Expression and Immunogenicity in Hepatocellular Carcinoma.

Cancer testis (CT) antigens have received particular attention in cancer immunotherapy. OY-TES-1 is a member of CT antigens. This study was to evaluate OY-TES-1 expression and immunogenicity in hepatocelluar carcinoma (HCC). OY-TES-1 mRNA expression was detected in 56 HCC tissues and 5 normal liver tissues by reverse transcriptase PCR (RT-PCR). Of the 56 cases of HCC tissues tested, 37 cases had tumor and matched adjacent non-cancer tissues and were subjected to both RT-PCR and quantitative real-time PCR. OY-TES-1 protein was subsequently observed on a panel of tissue microarrays. Sera from patients were tested for OY-TES-1 antibody by ELISA. To identify OY-TES-1 capable of inducing cellular immune response, OY-TES-1 protein was used to sensitize dentritic cells and the cytotoxicity effect was measured in vitro. The results showed that OY-TES-1 mRNA was highly expressed in 41 of the 56 (73.21%) HCC tissues, whereas none in 5 normal liver tissues. OY-TES-1 mRNA was frequently expressed not only in HCC tissues (72.97%, 27/37), but also in paired adjacent non-cancer tissues (64.86%, 24/37). But the mean expression level of OY-TES-1 mRNA in HCC tissues was significantly higher than that in adjacent non-cancer tissues (0.76854 vs. 0.09834, P=0.021). Immunohistochemistry showed that OY-TES-1 protein expression was detected in 6 of the 49 cases of HCC tissues, and absent in 9 cases of normal liver and 6 cases of cirrhosis tissues. Seropositivity was detected in 10 of the 45 HCC patients, but not detected in 17 cirrhosis patients and 76 healthy donors. The specific cytotoxic T cells elicited by OY-TES-1 could kill HLA-A2+ HCC cell line which expressed OY-TES-1. The target lysis was mainly HLA class I -dependent and could be blocked by antibodies against monomorphic HLA class I but not HLA class II molecule. In summary, OY-TES-1 expression is up-regulated in HCC tissues and can be recognized by humoral and cellular responses, which suggests that OY-TES-1 is an attractive target for tumor immunotherapy in HCC.

Involvement of X-chromosome Reactivation in Augmenting Cancer Testis Antigens Expression: A Hypothesis.

Cancer testis antigens (CTAs) are attractive targets for tumor immunotherapy because of their tumor-specific expression. Since more than half of confirmed CTAs are located on the X-chromosome, we asked whether there is a link between CTA expression and X-chromosomes. Recent reports have shown that reactivation of the inactive X-chromosome, known as X-chromosome reactivation (XCR), a unique phenomenon that exists in many high-risk tumors in women, can transform the expression of many X-linked genes from monoallelic to biallelic. In this review, we discuss the link between CTA and XCR with the hopes of providing some novel insights into tumor biology.

Down-regulation of cancer/testis antigen OY-TES-1 attenuates malignant behaviors of hepatocellular carcinoma cells in vitro.

Cancer/testis (CT) antigens are normally expressed in testis and overexpressed in various tumor types. However, their biological function is largely unknown. OY-TES-1, one of cancer/testis (CT) antigens, is reported overexpression in hepatocellular carcinoma (HCC). And we assumed that OY-TES-1 contribute to oncogenesis and progression of HCC. In this study, we knocked down OY-TES-1 by small interference RNA (siRNA) in HCC cell lines (HepG2 and BEL-7404) to verify this assumption and evaluate its potential as therapeutic targets for HCC. We showed that down regulation of OY-TES-1 decreased cell growth, induced the G0/G1 arrest and apoptosis, and prevented migration and invasion in the two HCC cell lines. Further analysis revealed that down regulation of OY-TES-1 increased expression of apoptosis-regulated protein caspase-3, and decreased expression of cell cycle-regulated protein cyclin E, migration/invasion-regulated proteins MMP2 and MMP9. These findings may shed light on the gene therapy about the OY-TES-1 expression in HCC cells.

Overexpression of MAGE-D4 in colorectal cancer is a potentially prognostic biomarker and immunotherapy target.

Melanoma-associated antigen D4 (MAGE-D4) is a novel member of MAGE family. This study aimed to examine the expression and immunogenicity of MAGE-D4 in colorectal cancer (CRC) to determine its potential as a prognosis and immunotherapeutic target. The expression of MAGE-D4 mRNA and protein was determined by RT-PCR and immunohistochemistry (IHC) in CRCs with paired adjacent non-tumor tissues, colorectal adenomas and normal colorectal tissues, respectively. Sera from 64 CRC patients were tested for MAGE-D4 antibody by ELISA. MAGE-D4 mRNA was more frequently expressed in CRCs (76.7%, 46/60) than in adjacent non-tumor tissues (15.0%, 9/60). MAGE-D4 protein was detected in all the CRC tissues tested, 70.0% of which showed high expression. There was no MAGE-D4 protein detected in any paired adjacent non-tumor tissue. No MAGE-D4 expression was found in colorectal adenomas and normal colorectal tissues by either RT-PCR or immunohistochemistry. Patients with high MAGE-D4 protein expression had significantly shorter overall survival than those with low MAGE-D4 protein expression (median, 68.6 vs 122.2 months; P=0.030). Furthermore, multivariate analysis exhibited high MAGE-D4 protein expression had a trend toward an independent prognostic factor (hazard ratio: 6.124; P=0.050). Humoral immunity to MAGE-D4 was detected in 12 of 64 (18.8%) CRC patients' sera but not in 77 healthy donors. There was no correlation between MAGE-D4 expression, serum antibody and clinicopathological parameters. These findings suggest MAGE-D4 may serve as a potentially prognostic biomarker and an attractive target of immunotherapy in CRC.

High expression and frequently humoral immune response of melanoma-associated antigen D4 in glioma.

MAGE-D4 is a novel member of MAGE super-family. It has preliminarily been demonstrated that MAGE-D4 mRNA is not expressed in majority of normal tissues except for brain and ovary in which only trace amount of MAGE-D4 mRNA can be detected, but predominantly expressed in glioma. MAGE-D4 protein expression and its immunogenicity in glioma have not been elucidated well. This study was designed to analyze MAGE-D4 expression both at mRNA and protein level, characteristic of humoral immune response, and their relationships with glioma patients' clinicopathological parameters. Recombinant MAGE-D4 protein and antiserum were generated. Quantitative RT-PCR analysis revealed that MAGE-D4 mRNA expression was overall up-regulated in 41 glioma specimens compared with that in 14 normal brain tissues. Immunohistochemistry analysis showed that 78% (21/27) glioma tissues expressed MAGE-D4 protein, which was predominantly located in the cytoplasm of tumor cells, but absent in any neuroglia cell of normal brain tissues. ELISA analysis demonstrated that humoral response against MAGE-D4 was detected in 17% (7/41) of glioma patients' sera but not in 77 healthy donors. No apparent correlation was observed between the expression and immunogenicity of MAGE-D4 with clinicopathological parameters of glioma. In summary, these results indicate that MAGE-D4 is highly expressed in glioma and can develop specifically humoral response in glioma patients, which supports that it may be a promising biomarker for glioma diagnosis and immunotherapy.

MAGED4 expression in glioma and upregulation in glioma cell lines with 5-aza-2'-deoxycytidine treatment.

Melanoma-associated antigen (MAGE) family genes have been considered as potentially promising targets for anticancer immunotherapy. MAGED4 was originally identified as a glioma-specific antigen. Current knowledge about MAGED4 expression in glioma is only based on mRNA analysis and MAGED4 protein expression has not been elucidated. In the present study, we investigated this point and found that MAGED4 mRNA and protein were absent or very lowly expressed in various normal tissues and glioma cell line SHG44, but overexpressed in glioma cell lines A172,U251,U87-MG as well as glioma tissues, with significant heterogeneity. Furthermore, MAGED4 protein expression was positively correlated with the glioma type and grade. We also found that the expression of MAGED4 inversely correlated with the overall methylation status of the MAGED4 promoter CpG island. Furthermore, when SHG44 and A172 with higher methylation were treated with the DNA demethylating agent 5-aza-2'-deoxycytidine (5-AZA-CdR) reactivation of MAGED4 mRNA was mediated by significant demethylation in SHG44 instead of A172. However, 5-AZA-CdR treatment had no effect on MAGED4 protein in both SHG44 and A172 cells. In conclusion, MAGED4 is frequently and highly expressed in glioma and is partly regulated by DNA methylation. The results suggest that MAGED4 might be a promising target for glioma immunotherapy combined with 5-AZA-CdR to enhance its expression and eliminate intratumor heterogeneity.

Knockdown of GCF2/LRRFIP1 by RNAi causes cell growth inhibition and increased apoptosis in human hepatoma HepG2 cells.

BACKGROUND: GC-binding factor 2 (GCF2) is a transcriptional regulator that represses transcriptional activity of the epidermal growth factor receptor (EGFR) by binding to a specific GC-rich sequence in the EGFR gene promoter. In addition to this function, GCF2 has also been identified as a tumor-associated antigen and regarded as a potentially valuable serum biomarker for early human hepatocellular carcinoma (HCC) diagnosis. GCF2 is high expressed in most HCC tissues and cell lines including HepG2. This study focused on the influence of GCF2 on cell proliferation and apoptosis in HepG2 cells. MATERIALS AND METHODS: GCF2 expression at both mRNA and protein levels in HepG2 cells was detected with reverse transcription (RT) PCR and Western blotting, respectively. RNA interference (RNAi) technology was used to knock down GCF2 mRNA and protein expression. Afterwards, cell viability was analyzed with a Cell Counting Kit-8 (CCK-8), and cell apoptosis and caspase 3 activity by flow cytometry and with a Caspase 3 Activity Kit, respectively. RESULTS: Specific down-regulation of GCF2 expression caused cell growth inhibition, and increased apoptosis and caspase 3 activity in HepG2 cells. CONCLUSIONS: These primary results suggest that GCF2 may influence cell proliferation and apoptosis in HepG2 cells, and also provides a molecular basis for further investigation into the possible mechanism at proliferation and apoptosis in HCC.

Cancer testis antigen OY-TES-1 expression and serum immunogenicity in colorectal cancer: its relationship to clinicopathological parameters.

Cancer testis (CT) antigens are attractive targets for cancer immunotherapy because their expression is restricted in normal germ line tissues but frequently detected in variety of tumors. OY-TES-1 is identified as a member of CT antigens. Current knowledge about OY-TES-1 expression in colorectal cancer (CRC) is solely based on mRNA analysis. None of previous researches has studied OY-TES-1 at protein level. In this study, OY-TES-1 polyclonal antibody was generated. The expression of OY-TES-1 mRNA and protein was detected by RT-PCR and immunohistochemistry in 60 CRC and paired adjacent non-tumor tissues, 24 colorectal adenoma and 3 normal colon tissues, respectively. Sera from 73 CRC patients were also tested for OY-TES-1 antibody by ELISA. Our results showed that the frequency of OY-TES-1 mRNA expression was statistically higher in CRC (73.3%, 44/60) than that in adjacent non-tumor tissue (55.0%, 33/60) and colorectal adenoma (45.8%, 11/24). For the first time, OY-TES-1 protein expression was found in (43.3%, 26/60) of CRC tissues, but absent in any of adjacent non-tumor and colorectal adenoma tissues. No OY-TES-1 expression was found in normal colon by either RT-PCR or immunohistochemistry. Furthermore, OY-TES-1 protein expression was correlated with tumor invasion stage (P=0.004) and histological grade (P=0.040). Anti-OY-TES-1 antibody was detected in (9.6%, 7/73) of CRC patients' sera but not in 76 healthy donors. This finding demonstrates that OY-TES-1 is frequently expressed in CRC and is able to induce humoral immune response spontaneously in CRC patients, suggesting that it might be a promising immunotherapy target for CRC.

Soluble expression of recombinant human SMP30 for detecting serum SMP30 antibody levels in hepatocellular carcinoma patients.

Senescence marker protein 30 (SMP30), a hepatocellular carcinoma (HCC) associated antigen, was earlier shown by our research group to be highly expressed in HCC paracancerous tissues, but have low levels in HCC tissues. In order to detect anti-SMP30 antibody in serum of HCC patients, we established pET30a-SMP30 and pColdIII-SMP30 expression systems in Escherichia coli. However, the expression product was mainly in the form of inclusion bodies. In this research, we used several combinations of chaperones, four molecular chaperone plasmids with pET30a-SMP30 and five molecular chaperone plasmids with pColdIII-SMP30 to increase the amount of soluble protein. Results showed that co-expression of HIS-SMP30 with pTf16, combined with the addition of osmosis-regulator, and a two-step expression resulted in the highest enhancement of solubility. A total of 175 cases of HCC serum were studied by ELISA to detect anti- SMP30 antibody with recombinant SMP30 protein. Some 22 were positive and x2 two-sided tests all showed P>0.05, although it remained unclear whether there was a relationship between positive cases and clinical diagnostic data.

Artificial antigen-presenting cells plus IL-15 and IL-21 efficiently induce melanoma-specific cytotoxic CD8+ CD28+ T lymphocyte responses.

OBJECTIVE: To develop a novel artificial antigen-presenting system for efficiently inducing melanoma-specific CD8(+) CD28(+) cytotoxic T lymphocyte (CTL) responses. METHODS: Cell-sized Dynabeads® M-450 Epoxy beads coated with H-2K(b): Ig-TRP2180-188 and anti-CD28 antibody were used as artificial antigen-presenting cells (aAPCs) to induce melanoma-specific CD8(+)CD28(+) CTL responses with the help of IL-21 and IL-15. Dimer staining, proliferation, ELISPOT, and cytotoxicity experiments were conducted to evaluate the frequency and activity of induced CTLs. RESULTS: Dimer staining demonstrated that the new artificial antigen-presenting system efficiently induced melanoma TRP2-specific CD8(+)CD28(+)CTLs. Proliferation and ELISPOT assays indicated that the induced CTLs rapidly proliferate and produce increased IFN- γ under the stimulation of H-2K(b): Ig-TRP2-aAPCs, IL-15, and IL-21. In addition, cytotoxicity experiments showed that induced CTLs have specific killing activity of target cells. CONCLUSIONS: The new artificial antigen-presenting system including aAPCs plus IL-21 and IL-15 can induce a large number of antigen-specific CD8(+) CD28(+) CTLs against the melanoma. Our study provides evidence for a novel adoptive immunotherapy against tumors.

Knockdown of OY-TES-1 by RNAi causes cell cycle arrest and migration decrease in bone marrow-derived mesenchymal stem cells.

OY-TES-1 is a member of the CTA (cancer-testis antigen) group expressed in a variety of cancer and restrictedly expressed in adult normal tissues, except for testis. To determine whether MSCs (mesenchymal stem cells) express OY-TES-1 and its possible roles on MSCs, OY-TES-1 expression in MSCs isolated from human bone marrow was tested with RT (reverse transcription)-PCR, immunocytochemistry and Western blot. Using RNAi (RNA interference) technology, OY-TES-1 expression was knocked down followed by analysing cell viability, cell cycle, apoptosis and migration ability. MSCs expressed OY-TES-1 at both mRNA and protein levels. The down-regulation of OY-TES-1 expression in these MSCs caused cell growth inhibition, cell cycle arrest, apoptosis induction and migration ability attenuation. Through these primary results it was suggested that OY-TES-1 may influence the biological behaviour of MSCs.

[Construction of eukaryotic expression vector encoding ACRBP and its expression in hepatocarcinoma cells].

AIM: To construct the eukaryotic expression vector pEGFP-N1/ACRBP and stably express ACRBP in human hepatocarcinoma cells, providing functional clues for ACRBP. METHODS: A recombinant plasmid pMAL-C2/ACRBP was used as a template to amplify ACRBP cDNA. The PCR product was ligated into an eukaryotic expression vector pEGFP-N1 to construct a recombinant plasmid pEGFP-N1/ACRBP. Then the pEGFP-N1/ACRBP was transfected by Fugene HD into ACRBP-negative HepG2 cells. The stably transfected clones were selected by G418. RT-PCR and immunohistochemistry were used to detect the expression of ACRBP in HepG2 cells. RESULTS: The eukaryotic expression vector pEGFP-N1/ACRBP was constructed and confirmed by sequencing. The stably transfected HepG2 cells expressed ACRBP. CONCLUSION: The eukaryotic expression vector pEGFP-N1/ACRBP has been successfully constructed and transfected into HepG2 cells, resulting in stable expression of ACRBP.