Prognostic significance of CKS2 and CD47 expression in patients with gastric cancer who underwent radical gastrectomy.

To investigate the protein expression levels of cyclin-dependent kinase subunit 2 (CKS2) and the cluster of differentiation (CD) 47 in gastric cancer (GC) and their clinical significance. A total of 126 GC patients who underwent radical resection were selected as study subjects. Additionally, 32 patients with benign gastric tumour, 42 patients with low-grade intraepithelial neoplasia (LGIEN), and 49 patients with high-grade intraepithelial neoplasia (HGIEN) who underwent surgery were selected as the control groups. Immunohistochemistry was used to detect the expression of CKS2 and CD47 in surgical specimens. We statistically analysed the clinical significance of the expression of the two factors. (1) The positivity rates for CKS2 in benign gastric tumour tissue, LGIEN tissue, HGIEN tissue, and GC tissue gradually increased, that is, 6.3% (2/32), 30.9% (13/42), 38.8% (19/49), and 60.3% (76/126), respectively, and the positivity rates for CD47 were 18.8% (6/32), 38.1% (16/42), 46.9% (23/49), and 65.9% (83/126), respectively. (2) High expression of CKS2 and CD47 were associated with tumour diameter, Lauren classification, number of lymph node metastases, and TNM stage. In addition, the immunohistochemical scores for CKS2 and CD47 were positively correlated (r = .625, P = .000). (3) The median follow-up time of 126 patients was 46.5 months, and the overall survival (OS) rate was 40.5% (51/126). Survival analysis showed that compared with that in the CKS2 (-) group, the OS rate for patients in the CKS2 (+) group was significantly worse and that compared with the CD47 (-) group, the CD47 (+) group had significantly worse OS (30.1% vs 60.5%, χ2  = 15.67, P = .000). (4) The OS rates of CKS2 (+) CD47 (+) group, CKS2 (+) CD47 (-) group, CKS2 (-) CD47 (+) group, and CKS2 (-) CD47 (-) group were 20.0% (13/65), 58.3% (7/12), 57.1% (8/14), 65.7% (23/35), respectively, the prognosis of patients in CKS2 (+) CD47 (+) group was significantly poor. High expression levels of CKS2 and CD47 were closely related to the occurrence of GC and can be used as independent risk factors to assess the prognosis of patients.

microRNA-222 Attenuates Mitochondrial Dysfunction During Transmissible Gastroenteritis Virus Infection.

Transmissible gastroenteritis virus (TGEV) is a member of Coronaviridae family. Our previous research showed that TGEV infection could induce mitochondrial dysfunction and upregulate miR-222 level. Therefore, we presumed that miR-222 might be implicated in regulating mitochondrial dysfunction induced by TGEV infection. To verify the hypothesis, the effect of miR-222 on mitochondrial dysfunction was tested and we showed that miR-222 attenuated TGEV-induced mitochondrial dysfunction. To investigate the underlying molecular mechanism of miR-222 in TGEV-induced mitochondrial dysfunction, a quantitative proteomic analysis of PK-15 cells that were transfected with miR-222 mimics and infected with TGEV was performed. In total, 4151 proteins were quantified and 100 differentially expressed proteins were obtained (57 upregulated, 43 downregulated), among which thrombospondin-1 (THBS1) and cluster of differentiation 47 (CD47) were downregulated. THBS1 was identified as the target of miR-222. Knockdown of THBS1 and CD47 decreased mitochondrial Ca2+ level and increased mitochondrial membrane potential (MMP) level. Reversely, overexpression of THBS1 and CD47 elevated mitochondrial Ca2+ level and reduced mitochondrial membrane potential (MMP) level. Together, our data establish a significant role of miR-222 in regulating mitochondrial dysfunction in response to TGEV infection.

A review of the current understanding and clinical utility of miRNAs in esophageal cancer.

BACKGROUND: MicroRNAs (miRNAs) are a class of small, well-conserved, non-coding RNAs that regulate the translation of RNAs. They have a role in biological and pathological process including cell differentiation, apoptosis, proliferation and metabolism. Since their discovery, they have been shown to have a potential role in cancer pathogenesis through their function as oncogenes or tumor suppressors. A substantial number of miRNAs show differential expression in esophageal cancer tissues, and so have been investigated for possible use in diagnosis. Furthermore, there is increasing interest in their use as prognostic markers and determining treatment response, as well as identifying their downstream targets and understanding their mode of action. METHODS: We analyzed the most recent studies on miRNAs in esophageal cancer and/or Barrett's esophagus (BE). The publications were identified by searching in PuBMed for the following terms: Barrett's esophagus and microRNA; esophageal cancer and microRNA. RESULTS: Four miRNAs (mi-R-25, -99a, -133a and -133b) showed good potential as diagnostic markers and interestingly five (mi-R-21, -27b, -126, - 143 and -145) appeared to be useful both as diagnostic and prognostic/predictive markers. CONCLUSION: The data so far on miRNAs in esophageal carcinogenesis is promising but further work is required to determine whether miRNAs can be used as biomarkers, not only in the clinical setting or added to individualized treatment regimes but also in non-invasive test by making use of miRNAs identified in blood.

[Radix Tetrastigme Polysaccharide Promotes Antitumor Immune Response 
in Lewis Lung Cancer Mice].

BACKGROUND: Lung cancer has a high incidence and mortality rate, but the treatment of lung cancer still lacks low toxicity and efficient anti-tumor drugs. Polysaccharide from radix tetrastigme has development value in anti-tumor treatment methods. This study was to observe the effect of polysaccharide from radix tetrastigme on immune response of Lewis lung cancer mice and explore its molecular mechanism. METHODS: Lewis lung cancer mouse models were established and randomly grouped. The spleen polypeptide group was intragastric with 50 mg/kg spleen polypeptide, and the radix tetrastigme polysaccharide low, medium and high dose groups were intragastric with 62.5, 125 and 250 mg/kg radix tetrastigme polysaccharide, respectively, and the model group and the control group were intragastric with equivolume normal saline. Tumor formation and metastasis were compared. Haematoxylin-eosin (HE) staining was used to observe the pathological changes of tumor cells. Macrophage phagocytosis, apoptosis, M1/M2 polarization, T cell subsets and cytokine levels in peripheral blood were detected by flow cytometry. The proliferation activity of macrophages was detected by methyl thiazolyldiphenyl tetrazolium (MTT) assay. Dendritic cell (DC) antigen presenting function was detected by chlorophenol red-ß-D-galactopyranoside (CPRG) method. Tumor tissue differentiation antigen cluster 47 (CD47) mRNA and protein expression and macrophage signal regulatory protein α (SIRRP α) expression were detected by real time quantitative polymerase chain reaction (RT-qPCR) and Western blot (WB). RESULTS: The tumor inhibition rates and anti-metastasis rates in the 3-dose radix tetrastigme polysaccharide group and the spleen polypeptide group were higher than those in the model group, and the pathological injury of tumor tissue were severer, and the positive rate of phagocytosis of ink by macrophages and the efficiency of phagocytosis of tumor cells were increased; the apoptosis rate of macrophages was decreased; the proliferation activity of macrophages, polarization ratio of macrophages to M1 type, DC antigen presenting ability, CD4+, CD4+/CD8+ levels were increased; the level of serum tumor necrosis factor α (TNF-α), interleukin-1ß (IL-1ß), and the expression of tumor tissue CD47, macrophage SH2-containing protein tyrosine phosphatase 1 (SHP-1), SH2-containing protein tyrosine phosphatase 2 (SHP-2), and phosphorylation signal regulatory protein α (p-SIRPα) were decreased, and the differences were statistically significant (P<0.05). There were no significant differences in the above indexes between low-dose radix tetrastigme polysaccharide group and spleen polypeptide group (P>0.05), and the effects of radix tetrastigme polysaccharide were dose-dependent. CONCLUSIONS: Radix tetrastigme polysaccharide can inhibit tumor growth, metastasis and immune response in Lewis lung cancer mice, and its mechanism may be related to inhibiting SIRP/CD47 signaling pathway.

Design single-stranded DNA aptamer of cluster of differentiation 47 protein by stochastic tunnelling-basin hopping-discrete molecular dynamics method.

The formation of the Cluster of Differentiation 47 (CD47, PDB code: 2JJT)/signal regulatory protein α (SIRPα) complex is very important as it protects healthy cells from immune clearance while promoting macrophage phagocytosis for tumour elimination. Although several antibodies have been developed for cancer therapy, new function-blocking aptamers are still under development. This study aims to design the aptamer AptCD47, which can block the formation of the CD47/SIRPα complex. This study employs the MARTINI coarse-grained (CG) force field and the stochastic tunnelling-basin hopping-discrete molecular dynamics (STUN-BH-DMD) method to identify the most stable AptCD47/CD47 complexes. Coarse-grained molecular dynamics (CGMD) simulations were used to obtain root-mean-square deviation (RMSD) and root-mean-square fluctuation (RMSF) analyses. The results demonstrate that the formation of AptCD47/CD47 complexes renders the CD47 structure more stable than the single CD47 molecule in a water environment. The minimum energy pathway (MEP) obtained by the nudged elastic band (NEB) method indicates that the binding processes of 5'-ATTCAATTCC-3' and 5'-AGTGCAATCT-3' to CD47 are barrierless, which is much lower than the binding barrier of SIRPα to CD47 of about 14.23 kcal/mol. Therefore, these two AptCD47/CD47 complexes can create a high spatial binding barrier for SIRPα, preventing the formation of a stable CD47/SIRPα complex. The proposed numerical process with the MARTINI CG force field can be used to design CD47 aptamers that efficiently block SIRPα from binding to CD47.Communicated by Ramaswamy H. Sarma.

Prognostic implications of combined high expression of CD47 and MCT1 in breast cancer: a retrospective study during a 10-year period.

Background: Clinical outcome after surgery of breast cancer needs more prognostic markers to predict currently. Cluster of differentiation 47 (CD47), due to its overexpression in various tumors and ability to inhibit phagocytosis, has been identified as a new immune checkpoint. Monocarboxylate transporter 1 (MCT1) is a protein involved in the immunomodulatory activities of the tumor microenvironment (TME) by maintaining the pH through aerobic glycolysis. Methods: We explored the expression of CD47 and MCT1 in breast invasive ductal carcinoma specimens to determine their association with prognosis. A total of 137 breast invasive ductal carcinoma tissues were collected for CD47 and MCT1 immunohistochemical staining. Results: Statistically analyzed, our study first indicated that in both univariate and multivariate analyses, the coexpression of CD47 and MCT1 was an independent prognostic factor for a poor 10-year overall survival rate (10-OS) and 10-year progression-free survival rate (10-DFS) (P<0.05). In addition, the combined high expression of these two markers also led to worse OS and PFS rates in the TNM (II + III), histologic grade (I + II), HER2 overexpression and basal-like subgroups. High expression of CD47 and MCT1 and combined high expression of CD47 and MCT1 were associated with clinicopathological parameters, such as histological grade, TNM stage, death status, and recurrence status in breast cancer patients. However, in the multivariate survival analysis, high expression of CD47 alone was not an independent prognostic factor for the 10-OS or the 10-DFS (P=0.104; P=0.153), and high expression of MCT1 alone was not an independent predictor for a poor 10-DFS (P=0.177) either. Conclusions: The coexpression of CD47 and MCT1 can serve as a prognostic biomarker leading to poor survival and an increased risk for recurrence, and this novel information could help guide the development of adjuvant therapy for breast cancer.

Expression of CD47 antigen in Reed-Sternberg cells as a new potential biomarker for classical Hodgkin lymphoma.

INTRODUCTION: CD47 over expression has been reported in several tumor subtypes. CD47 interacts with SIRPalpha on macrophages inhibiting phagocytic signal, providing a survival advantage to tumor. CD47, therefore, represents a valuable target for immunotherapy and is currently under clinical investigation. We aimed to study CD47 expression in Hodgkin Reed Sternberg cells (HRS). METHODS: We tested a polyclonal CD47 antibody (LifeSpan Biosciences, Seattle, WA) expression along with classical HRS cell markers on a tissue array of 16 classical Hodgkin Lymphoma (CHL) tumor biopsies obtained from newly diagnosed, non-selected patients (8 Female, 8 Male patients) in our institution from October 2016 to January 2018. Histologic subtypes were nodular sclerosis in 11 cases, mixed Cellularity in 3 cases and lymphocyte rich in 2 additional cases. Median age was 53 years (Range: 8, 74). Early stage disease was found in three patients without unfavorable prognostic factors according to EORTC and GHSG criteria, one patient with unfavorable prognostic factors and nine patients had advanced disease. Bulk disease was present in one patient. Normal lymphoid tissue and normal prostate epithelium were used as normal controls as recommended by manufacturer. Approval from the Local Ethical committee was obtained before any analysis. RESULTS: CD47 was overexpressed on all HRS cells with a characteristic dot-like pattern in 13/13 cases of CHL. HRS clearly expressed CD47 more intensely than infiltrating T and stromal cells. DISCUSSION: We propose that HRS cells, by up-regulating CD47, might avoid innate immunity check on tumor growth, which could be circumvented using blocking monoclonal antibodies.

Targeting cluster of differentiation 47 improves the efficacy of anti-cytotoxic T-lymphocyte associated protein 4 treatment via antigen presentation enhancement in pancreatic ductal adenocarcinoma.

Treatment with cluster of differentiation 47 (CD47) monoclonal antibody has exhibited promising antitumor effects in various preclinical cancer models. However, its role in pancreatic ductal adenocarcinoma (PDAC) remains unclear. In the present study, the CD47 expression level was measured in PDAC patient samples. The effects of CD47 on antigen presentation and anti-tumor immunity were evaluated using phagocytotic assays and animal models. The results indicated that CD47 was overexpressed in the tumor tissue of PDAC patients compared with that in normal adjacent tissues. In the human samples, antigen-presenting cells (macrophages and dendritic cells) in tumors with high CD47 expression demonstrated low CD80 and CD86 expression levels. In an in vitro co-culture tumor cell system, CD47 overexpression was observed to inhibit the function of phagocytic cells. Furthermore, in a PDAC mouse model, CD47 overexpression was indicated to reduce antigen-presenting cell tumor infiltration and T-cell priming in tumor-draining lymph nodes. Anti-CD47 treatment appeared to enhance the efficacy of the approved immune checkpoint blockade agent anti-cytotoxic T-lymphocyte associated protein 4 (anti-CTLA4) in suppressing PDAC development in a mouse model. Therefore, it was concluded that CD47 overexpression suppressed antigen presentation and T-cell priming in PDAC. Anti-CD47 treatment may enhance the efficacy of anti-CTLA4 therapy and may therefore be a potential strategy for the treatment of PDAC patients in the future.

miR-128 Regulates Tumor Cell CD47 Expression and Promotes Anti-tumor Immunity in Pancreatic Cancer.

Pancreatic adenocarcinoma (PDAC) is a highly fatal disease worldwide. MicroRNAs (miRNAs) could regulate the protein-coding RNAs related to tumor growth, invasion, and immune evasion. Therefore, the investigation of novel miRNAs may be helpful in the development of more effective therapies for PDAC. In this study, we investigated the role and mechanism of action of miR-128 in PDAC. By using bioinformatics methods, we found that decreased expression of miR-128 was associated with poor overall survival of PDAC. miR-128 was inversely correlated with cluster of differentiation 47 (CD47), which was positively related to zinc finger E-box-binding homeobox 1 (ZEB1) in PDAC. Through in vivo experiments, we found that miR-128 could suppress the growth and metastasis of PDAC. Analysis of the immune microenvironment demonstrated that overexpression of miR-128 on tumor cells could increase the percentages of dendritic cells (DCs), CD8+ T lymphocytes, and natural killer T cells (NKT) in the tumor and spleen, consequently enhancing anti-tumor immunity. In vitro assays showed that miR-128 could inhibit cell proliferation, clonogenicity, migration, and invasion in Panc02 cells and could also enhance the phagocytosis of macrophages and the activity of DCs. Western blot and qRT-PCR confirmed that miR-128 could regulate ZEB1 and further inhibit CD47 in pancreatic cancer cells. Therefore, we identified a novel regulatory anti-tumor mechanism by miR-128 in PDAC, which may serve as a novel therapy for PDAC.

Characterization of cluster of differentiation 47 expression and its potential as a therapeutic target in esophageal squamous cell cancer.

The increased expression of cluster of differentiation (CD)47 has been identified in a number of different tumor types and is recognized as an adverse prognostic factor that indicates an increased risk of mortality in patients. The binding of CD47 to signal regulatory protein α (SIRPα) inhibits the macrophage phagocytosis of tumor cells by triggering an inhibitory 'do not eat me' signal. This is one of the mechanisms used by tumor cells to evade immune surveillance. In the present study, CD47 levels and macrophage infiltration were assessed in patients with esophageal squamous cell cancer (ESCC). CD47-overexpressing ESCC cell lines were selected and human M2 macrophage phagocytic activity was measured. The results revealed that CD47 is highly expressed and macrophages are markedly infiltrated in cancerous tissue compared with non-cancerous tissue. High CD47 expression was detected in ESCC cell lines and the results of a phagocytosis assay indicated that human M2 macrophages phagocytized tumor cells in a dose-dependent manner following the blocking of CD47-SIRPα signaling by anti-CD47 antibodies. The results of the present study therefore support the use of anti-CD47 immunotherapy to treat patients with ESCC.

CD47 as a potential prognostic marker for oral leukoplakia and oral squamous cell carcinoma.

Cluster of differentiation (CD)47, which acts as a negative indicator for phagocytic cells, is overexpressed on the surface of multiple human solid tumor cell types. Avoiding phagocytosis by CD47 is required for the progression of solid tumors. The present study investigated the expression of CD47 in oral leukoplakia (OLK) and oral squamous cell carcinoma (OSCC), and preliminarily explored the impact of CD47 on the proliferation of OSCC cells. A total of 56 tissue samples, including 36 cases of OLK, 10 cases of OSCC and 10 cases of normal oral mucosa (NOM) were selected to detect the expression of CD47 by immunohistochemistry. For subgroup analysis, OLK samples were divided into OLK with low-risk dysplasia (LR-OLK) and OLK with high-risk dysplasia (HR-OLK). The subcellular localization of CD47 was determined by immunofluorescence in three OSCC cell lines (Tca8113, SCC-9 and Cal-27). The effect of CD47 antibody on the proliferation of the Cal-27 cell line was analyzed using the Cell Counting kit-8 assay. CD47 expression in OLK and OSCC lesions was significantly higher than in NOM (P<0.05). Compared with LR-OLK, the expression of CD47 in HR-OLK and OSCC cells was upregulated (P=0.0327 and P=0.0048, respectively). CD47 was highly expressed in OSCC cell lines (Tca8113, Cal-27 and SCC-9) and weakly expressed in normal oral keratinocytes. The proliferation of Cal-27 cells was inhibited by CD47 antibody in a concentration and time-dependent manner. CD47 may be a reliable biomarker for predicting the progression of oral precancer and cancer, and it may serve as an important molecular target for designing a novel therapy for oral cancer.

Molecular functions of SIRPα and its role in cancer.

Signal regulatory protein α (SIRPα), also known as cluster of differentiation (CD)172a or Src homology 2 domain-containing phosphatase substrate-1, is a cell surface receptor expressed on myeloid and hematopoietic stem cells and neurons. Accumulating data suggests an important role of SIRPα in cell signaling as a negative regulator of the phosphatidylinositol 3-kinase signaling and mitogen-activated protein kinase pathways. In various cancers, including prostate, breast and liver, as well as astrocytoma and myeloid malignancies, downregulation of SIRPα is frequently observed, resulting in activation of these downstream signaling pathways. In turn, cell proliferation, transformation, migration and invasion may occur. Recently, it has been reported that blocking CD47, an anti-phagocytic signal expressed on tumor cells and an SIRPα ligand, may serve as a promising therapeutic approach, particular for the treatment of acute myeloid leukemia. In the present review, the current findings on SIRPα are summarized, with particular focus on its role in cancer.