Effect of Dickkopf-1 regulated Wnt pathway on transdifferentiation of hypoxia-induced lens epithelial cells / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To scrutinize the role of the Wnt/β-catenin signaling pathway in the epithelial-mesenchymal transition(EMT)of lens epithelial cells under hypoxic conditions, and to further analyze the effect of Dickkopf-1(DKK-1)expression on EMT of lens epithelial cells.METHODS: Human lens epithelial cells(HLEB3 cells)were propagated in vitro and then separated into two groups: one exposed to standard oxygen levels, added DMEM culture solution containing 10% FBS(normoxic group)and another subjected to low oxygen levels(hypoxic group). The hypoxic condition was emulated by applying a concentration of 100 μmol/L cobalt chloride(CoCl2)for 6, 12, 24, and 48h. The utilization of immunofluorescence staining enabled the detection of Wnt3a and DKK-1 expressions, along with the expression and localization of β-catenin protein in these groups. The expression of DKK-1 mRNA was discerned by quantitative real-time polymerase chain reaction(qRT-PCR).RESULTS: Immunofluorescence assays indicated an escalating trend in the Wnt3a and DKK-1 protein expression, which corresponded with the increasing duration of hypoxia. Likewise, an intensified nuclear accumulation of β-catenin protein was observed to be directly proportional to the length of hypoxia treatment. The qRT-PCR demonstrated that the difference in DKK-1 mRNA expression between the normoxic group and the group exposed to hypoxia for 6h was not statistically significant(P>0.05), whereas the DKK-1 mRNA expression of the 12, 24, and 48h hypoxia groups were significantly increased(P<0.001).CONCLUSION: Hypoxia can activate Wnt/β-catenin pathway in lens epithelial cells and induce the expression of DKK-1, thus regulating the Wnt/β-catenin pathway and affecting the EMT process.

Advances in research and development of molecular targeted drugs for advanced gastric cancer / 中国肿瘤生物治疗杂志

@#[摘 要] 近年来，化疗基础上加用抗表皮生长因子受体2药物、抗血管生成药物及免疫检查点抑制剂，不仅可提高晚期胃癌（GC）患者治疗的有效率，而且可明显改善患者预后。然而，目前晚期GC患者治疗后的生存获益远落后于肺癌、结直肠癌及乳腺癌等实体肿瘤，靶向治疗仍需进一步探索。随着分子生物学技术的发展，新的治疗靶点如Claudin 18.2、基质金属蛋白酶（MMP）、Dickkopf相关蛋白1（DKK-1）、RAD3相关蛋白激酶（ATR）被发现在GC细胞中表达，针对这些靶点的药物逐渐在临床治疗中崭露头角，并显示出较好的临床应用前景。阐述晚期GC治疗中靶点的作用机制及靶向药物的研究进展，对提高GC的临床治疗疗效具有重要意义。

Dickkopf-1 inhibits the secretion of MUC5AC induced by Mycoplasma pneumoniae P1-C in mouse lung epithelial cells / 生物工程学报

Mycoplasma pneumoniae is the most common pathogen of respiratory tract infection in children and adults. Clinical observation shows that M. pneumoniae infection can cause massive mucus secretion in the respiratory tract, which makes the breathing of patients difficult. Studies have shown that M. pneumoniae infection can cause massive secretion of mucin 5AC (MUC5AC). Adhesin P1 plays an important role in the pathogenesis of M. pneumoniae infection by mediating the adhesion of pathogens to host cells, and the C-terminal residues of P1 (P1-C) are immunogenic. This study investigated the molecular mechanism of Wnt/β-catenin signaling pathway inhibitor Dickkopf-1 (DKK1) in the secretion of MUC5AC in mouse airway epithelial cells (MAECs) induced by P1-C. Scanning electron microscope and hematoxylin-eosin staining were used to observe the effect of P1-C on mucus secretion of MAECs. Protein chip was used to detect the secretion of cytokines and analyse the enrichment of related signaling pathways induced by P1-C in MAECs. Periodic acid schiff stain (PAS) staining, Tunel staining and Masson staining were used to detect the damage of the lungs of mouse exposed to P1-C. Immunohistochemistry was used to detect the secretion of MUC5AC expression, and Western blotting was used to reveal the molecular mechanism of DKK1-regulated secretion of MUC5AC induced by P1-C protein in MACES. The results showed that P1-C induced the massive secretion of mucus and inflammatory factors in MAECs. During P1-C infection, DKK1 down-regulated janus kinase 2 (JAK2), phosphorylation signaling and transcription activator 1 (p-STAT1) and phosphorylation signaling and activator of transcription 3 (p-STAT3) expression. Overexpression of DKK1 significantly up-regulated the expression of MUC5AC repressor transcription factor fork-head box protein A2 (FOXA2). At the same time, the expression of MUC5AC induced by P1-C was inhibited significantly. It is speculated that DKK1 can effectively reduce the secretion of MUC5AC in MAECs induced by P1-C by inhibiting the JAK/STAT1-STAT3 signaling pathway and up-regulating the expression of FOXA2.

Levels of DKK-1, MIP-1α and IL-17 in gingival crevicular fluid and serum of patients with chronic periodontitis and their clinical significance / 中国医师杂志

Objective:To investigate the level of gingival crevicular fluid and serum gingival sulcus fluid Dickkopf-1 (DKK-1), macrophage inflammatory protein-1α (MIP-1α) and interleukin (IL)-17 in patients with chronic periodontitis and their clinical significance.Methods:80 patients with chronic periodontitis (observation group) and 40 healthy periodontal subjects (control group) were prospectively selected. The gingival index (GI), bleeding index (BI), probe depth (PD), loss of attachment (AL) levels were compared between the two groups. The IL-6, IL-8, tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ), DKK1, MIP-1α and IL-17 levels in the gingival sulcus fluid and serum of the two groups were compared, and the correlation of DKK-1, MIP-1α and IL-17 levels with periodontal indexes and inflammatory factors in the observation group were analyzed. The DKK-1, MIP-1α and IL-17 levels in the gingival crevicular fluid and serum before and after treatment were compared among the patients with different disease degrees.Results:The levels of GI, BI, PD and AL in the observation group [(2.11±0.36)points, (3.76±0.65)points, (4.56±0.78)mm, (4.06±0.49)mm, respectively] were higher than those of the control group [(0.53±0.08)points, (1.61±0.33)points, (2.13±0.29)mm, 0 mm, respectively] (all P<0.05). The levels of IL-6, IL-8, TNF-α, DKK-1, MIP-1α and IL-17 in gingival crevicular fluid of the observation group [(65.23±9.30)ng/L, (310.19±42.95)ng/L, (40.46±9.70)ng/L, (13.70±3.62)μg/L, (19.67±8.14)μg/L, (315.84±53.76)pg/μl] were higher than those of the control group [(36.81±5.61)ng/L, (178.21±25.73)ng/L, (26.43±5.76)ng/L, (7.41±2.02)μg/L, (6.23±1.99)μg/L, (266.64±46.27)pg/μl, respectively] (all P<0.05). The serum levels of IL-8, TNF-α, DKK-1, MIP-1α and IL-17 in the observation group were also higher than those in the control group (all P<0.05). In the observation group, the levels of DKK-1, MIP-1α and IL-17 in gingival crevicular fluid and serum were positively correlated with eriodontal indexes (GI, BI, PD, AL) and the IL-8 and TNF-α levels (all P<0.05). In the observation group, the levels of DKK-1, MIP-1α and IL-17 in gingival crevicular fluid and serum of mild patients were lower than those of moderate to severe patients, and the levels of DKK-1, MIP-1α and IL-17 in mild and moderate to severe patients after treatment were also lower than those before treatment, with statistically significant difference (all P<0.05). Conclusions:The levels of DKK-1, MIP-1α and IL-17 in gingival crevicular fluid and serum of patients with chronic periodontitis are increased, which are closely related to the occurrence and development of chronic periodontitis. Detection of these indicators has certain significance for the diagnosis and treatment of the disease.

Application of β-catenin, Cyclin D1 and DKK1 in pathologically aided diagnosis of breast cancer / 国际肿瘤学杂志

Objective:To detect the expression differences of Wnt signaling pathway related molecules β-catenin, Cyclin D1 and Dickkopf-1 (DKK1) in breast disease tissues, and to explore their application value in pathologically aided diagnosis of breast cancer.Methods:From January 2008 to August 2019, 90 cases of breast tissue specimens in the Cancer Center of Guangzhou Medical University were collected, including 30 cases of breast hyperplasia, 30 cases of breast intraductal carcinoma and 30 cases of breast invasive ductal carcinoma. The expressions of β-catenin, Cyclin D1 and DKK1 in breast tissue of each group were detected by immunohistochemistry. Oncomine database and KM plotter database were used to analyze the expression differences of β-catenin, Cyclin D1 and DKK1 in breast cancer and normal breast tissues and their relationships with survival prognosis of patients with breast cancer, and to verify the results of immunohistochemistry. Receiver operating characteristic (ROC) curve was used to evaluate the efficacies of each molecule in pathologically aided diagnosis.Results:There were statistically significant differences in β-catenin, Cyclin D1 and DKK1 expressions among breast hyperplasia, breast intraductal carcinoma and breast invasive ductal carcinoma ( χ2=7.766, P=0.021; χ2=24.133, P<0.001; χ2=11.585, P=0.003). The expression of β-catenin in breast invasive ductal carcinoma group was significantly higher than that in breast intraductal carcinoma group and breast hyperplasia group ( Z=-2.367, P=0.018; Z=-2.462, P=0.014). The expression of Cyclin D1 in breast invasive ductal carcinoma group and breast intraductal carcinoma group was significantly higher than that in breast hyperplasia group ( Z=-4.166, P<0.001; Z=-4.174, P<0.001). The expression of DKK1 in breast invasive ductal carcinoma group and breast intraductal carcinoma group was significantly higher than that in breast hyperplasia group ( Z=-3.090, P=0.002; Z=-2.923, P=0.003). The results of bioinformatics analysis showed that compared with normal breast tissue, the expression of β-catenin mRNA in invasive breast cancer tissue increased by 2.33 times ( t=15.242, P<0.001), the expression of Cyclin D1 mRNA in breast intraductal carcinoma tissue increased by 6.64 times ( t=7.152, P=0.006), while the expression of DKK1 mRNA in normal breat tissue was 3.41 times higher than that in invasive breast cancer tissue, with no statistically significant difference ( t=-13.193, P>0.999). The median survival time of breast cancer patients in Cyclin D1 high expression group was 173.2 months, which was shorter than 228.9 months in low expression group ( P<0.001). The upper quartile survival time of breast cancer patients in DKK1 high expression group was 55.1 months, which was longer than 40.4 months in low expression group ( P<0.001). The breast invasive ductal carcinoma and breast intraductal carcinoma were combined into tumor group, the sum of the immunohistochemistry scores of β-catenin and Cyclin D1 minus the immunohistochemistry score of DKK1 was used as the combined scoring scheme 1, and the sum of β-catenin and Cyclin D1 immunohistochemistry score was used as the combined scoring scheme 2. ROC curve analysis showed that the area under the curve (AUC) of β-catenin, Cyclin D1, combined scoring scheme 1 and combined scoring scheme 2 for pathologically aided diagnosis of breast cancer were 0.65 ( P=0.080), 0.81 ( P<0.001), 0.70 ( P=0.023) and 0.78 ( P=0.001), respectively. The AUC of Cyclin D1 and combined scoring scheme 2 were ≥0.7, which had good value in pathologically aided diagnosis. Conclusion:Wnt signaling pathway related molecules Cyclin D1 and Cyclin D1 combined with β-catenin detection has a good value in the pathologically aided diagnosis of breast cancer.

Expression of plasma Dickkopf-1 in patients with rheumatoid arthritis and its correlation with peripheral blood T cell subsets / 北京大学学报(医学版)

OBJECTIVE@#To detect the levels of Dickkopf-1 (DKK-1) in the plasma of patients with rheumatoid arthritis (RA), and to analyze their correlation with peripheral blood T cell subsets and clinical indicators.@*METHODS@#Enzyme-linked immunosorbent assay (ELISA) was used to detect plasma DKK-1 levels in 32 RA patients and 20 healthy controls, and to record the various clinical manifestations and laboratory indicators of the RA patients, and flow cytometry to detect peripheral blood T cell subsets in the RA patients (Including Treg, nTreg, aTreg, sTreg, Teff, Tfh, CD4+CD161+T, CD8+T, CD8+CD161+T cells). The plasma DKK-1 levels between the two groups were ompared, and its correlation with peripheral blood T cell subsets and clinical indicators analyzed.@*RESULTS@#(1) The plasma DKK-1 concentration of the RA patients was (124.97±64.98) ng/L. The plasma DKK-1 concentration of the healthy control group was (84.95±13.74) ng/L. The plasma DKK-1 level of the RA patients was significantly higher than that of the healthy control group (P < 0.05), and the percentage of CD8+CD161+T cells in the peripheral blood of the RA patients was significantly higher than that of the healthy control group (P < 0.05). (2) The plasma DKK-1 level was positively correlated with erythrocyte sedimentation rate (r=0.406, P=0.021), DAS28 score (r=0.372, P=0.036), immunoglobulin G(r=0.362, P=0.042), immunoglobulin A(r=0.377, P=0.033); it had no correlation with age, course of disease, C-reactive protein, rheumatoid factor, anti-cyclic citrullinated peptide antibody, immunoglobulin M, complement C3, complement C4, white blood cell, neutrophil ratio. (3) The plasma DKK-1 level in the RA patients was positively correlated with the percentage of peripheral blood CD161+CD8+T cells (r=0.413, P=0.019);it had no correlation with Treg, nTreg, aTreg, sTreg, Teff, Tfh, CD4+CD161+T, CD8+T cells. (4) The percentage of CD161+CD8+T cells was negatively correlated with erythrocyte sedimentation rate (r=-0.415, P=0.004), C-reactive protein (r=-0.393, P=0.007), DAS28 score(r=-0.392, P=0.007), rheumatoid factor (r=-0.535, P < 0.001), anti-citrullinated protein antibody (r=-0.589, P < 0.001), immunoglobulin G(r=-0.368, P=0.012) immunoglobulin M (r=-0.311, P=0.035); it had no correlation with age, disease course, immunoglobulin A, complement C3, complement C4, white blood cell, and neutrophil ratio.@*CONCLUSION@#RA patients' plasma DKK-1 levels and the percentage of CD8+CD161+T cells in T cell subsets in peripheral blood increase, which may be related to the secretion of proinflammatory cytokines in patients; DKK-1 is involved in the regulation of bone homeostasis and can be used as a marker of bone destruction in RA.

DKK1 expression in head and neck squamous cell carcinoma: analysis of its clinical value and regulatory factors / 中国肿瘤生物治疗杂志

@#[Abstract] Objective: To explore the expression and regulation mechanism of Dickkopf-1 (DKK1) in head and neck squamous cell carcinoma (HNSCC) tissues. Methods: Based on the TCGA database, the relationship of DKK1 expression in HNSCC tissues and its methylation site with patients’prognosis was analyzed. GO and KEGG gene enrichment method were used to analyze the signaling pathways of DKK1 enrichment. STRING was used to analyze the interaction between DKK1 protein and other proteins. TargetScan was used to analyze the miRNAs that regulate the expression of DKK1, and the transcription factors of DKK1 were analyzed with the TRRUST website. Results: DKK1 gene was highly expressed in HNSCC tissues (P<0.01), and its expression level was significantly correlated with the HPV status, age, pathological grade, and clinical stage of patients (all P<0.05); the prognosis of HNSCC patients with high DKK1 expression was poorer than those with low DKK1 expression (P<0.01). There were 19 methylation sites in DKK1, 12 of which were significantly different between cancer tissues and normal tissues (P<0.05), and 11 sites were significantly related to the prognosis of HNSCC (P<0.05). In addition, miRNA, circRNA, lincRNA and transcription factors, etc. also participated in the regulation of DKK1. A total of 5 DKK1-related PPI networks that may involve in the occurrence, development, invasion and metastasis of HNSCC were obtained. Conclusion: DKK1 is highly expressed in HNSCC tissues and is a risk factor for poor prognosis of HNSCC patients. DKK1 plays an important role in the pathogenesis of HNSCC and is expected to become a potential target for HNSCC treatment.

Dickkopf 1 protein and its association with joint deterioration in rheumatoid arthritis: Systematic review / Dickkopf 1 protein and its association with joint deterioration in rheumatoid arthritis. Systematic review

ABSTRACT Background: Rheumatoid arthritis (RA) is an autoimmune disease that is mainly characterized by joint deterioration and decreased bone mineral density. The Dickkopf 1 protein (DKK1) exerts a negative regulatory function of the Wnt pathway involved in the differentiation of osteoblasts, and has been observed to be overexpressed in patients with RA. Objective: To provide updated information on current knowledge about the relationship between DKK1 serum levels and the presence of bone and joint damage in RA patients. Method: A qualitative systematic review was carried out in the PubMed, Embase, Cochrane and Scielo databases using the terms Dickkopf 1, DKK1, Dickkopf related protein 1, Rheumatoid Arthritis, and Bone biomarker. Results: A total of 12 studies were chosen that met the requirements of the search. These included 7 prospective cohorts, 4 cross-sectional studies, and 1 clinical trial. Of the 12 studies reviewed, 10 analyzed the relationship between serum DKK1 levels and the presence of bone damage as the primary outcome. One of them analyzed this relationship as a secondary outcome and another one the RSP01/DKK1 ratio. The results to date seem to indicate that DKK1 could have an active role in advanced stages of RA, but not in the initial phase. Conclusions: The DKK1 protein plays an essential pathophysiological role in the decrease of bone mass and joint remodelling, depending on the stage of the disease in patients with RA. Its role as a biomarker or therapeutic strategy would be an interesting alternative still under study.

RESUMEN Antecedentes: La artritis reumatoide (AR) es una enfermedad autoinmune caracterizada prin cipalmente por deterioro articular y disminución de la densidad mineral ósea. La proteína Dickkopf 1 (DKK1) ejerce una función reguladora negativa de la vía Wnt comprometida con la diferenciación de osteoblastos y se ha observado que puede estar sobreexpresada en pacientes con AR. Objetivo: Proveer información actualizada sobre el conocimiento de la asociación entre los niveles séricos de DKK1 y la presencia de dafño óseo y articular en pacientes con AR. Método: Se realizó una revisión sistemática cualitativa en las bases de datos Pubmed, Embase, Cochrane y Scielo utilizando los términos Dickkopf 1, DKK1, Dickkopf related pro tein 1, rheumatoid artrhitis, biomarcador, resorción ósea. Resultados: Se escogieron 12 estudios que llenaban los requisitos de la búsqueda; 7 fueron cohortes prospectivas, 4 estudios de corte transversal y uno ensayo clínico. De los 12 estudios revisados, 10 analizaron la asociación entre niveles séricos de DKK1 y presencia de dann o óseo como desenlace primario. Uno de ellos analizó esta asociación como desenlace secundario y otro la relación RSP01/DKK1. Los resultados hasta la fecha parecen indicar que la DKK1 tendría un papel activo en estadios avanzados de AR y no en la fase inicial. Conclusiones: La proteína DKK1 desempeña un papel fisiopatológico esencial en la disminu ción de la masa ósea y la remodelación articular, dependiendo de la fase de la enfermedad, en pacientes con AR. Su papel como biomarcador o estrategia terapéutica sería una interesante alternativa aún en estudio.

Value of combined measurement of serum alpha-fetoprotein, Dickkopf-1, and cytoskeleton-associated protein 4 in diagnosis of hepatocellular carcinoma / 临床肝胆病杂志

ObjectiveTo investigate the value of combined measurement of serum alpha-fetoprotein (AFP), Dickkopf-1 (DKK1), and cytoskeleton-associated protein 4 (CKAP4) in the diagnosis of hepatocellular carcinoma (HCC). MethodsA total of 122 patients with HCC (76 patients in the early stage), 152 patients with liver cirrhosis, and 105 patients with chronic hepatitis B, who were admitted to The First Affiliated Hospital of Soochow University from January 2013 to December 2017, were enrolled, and 101 individuals who underwent physical examination during the same period of time were enrolled as healthy control group. A one-way analysis of variance was used for comparison of continuous data between multiple groups, and the least significant difference t-test was used for further comparison between two groups; the chi-square test was used for comparison of categorical data between multiple groups. A binary logistic regression analysis was used to obtain the new variable of predicted probability, and the receiver operating characteristic (ROC) curve analysis was performed for each index and predicted probability to investigate the area under the ROC curve (AUC), sensitivity, and specificity of the three indices used alone or in combination. ResultsThe HCC group had significantly higher serum levels of AFP, DKK1, and CKAP4 than the liver cirrhosis group, the chronic hepatitis B group, and the healthy control groups (F=121.618, 84.559, and 91.769, P＜0.001). The combination of AFP, DKK1, and CKAP4 had an AUC of 0.967 (95% confidence interval ［CI］: 0.950-0.984), a sensitivity of 0.869, and a specificity of 0.980, which were significantly higher than the AUCs, sensitivities, and specificities of the three indices used alone (all P＜0.05). The combination of the three indices had an AUC of 0.965 (95%CI: 0.942-0.988), a sensitivity of 0.868, and a specificity of 0.980 in the diagnosis of early-stage HCC, which were significantly higher than the AUCs, sensitivities, and specificities of the three indices used alone (all P＜0.05). ConclusionCombined measurement of serum AFP, DKK1, and CKAP4 improves the accuracy, sensitivity, and specificity of HCC diagnosis and thus has an important clinical value in the screening for and early diagnosis of HCC.

Effect of DKK1 on proliferation, cell cycle and apoptosis of gastric cancer AGS cells / 中国肿瘤生物治疗杂志

@# Objective： ：To study the effect of silencing DKK1 (Dickkopf1) gene on the proliferation, cell cycle and apoptosis of gastric cancer AGS cells and the action mechanism. Methods： ：The DKK1-shRNA vector was constructed and transfected into AGS cells. The stably transfected cell lines were screened. The total protein and RNAof the transfected cells were extracted and the mRNAand protein expressions of DKK1 were detected by qPCR and WB, respectively. The experiment was divided into blank control group (Control), negative control group (shNC) and DKK1 silence group (DKK1-shRNA). CCK8 assay was used to detect the proliferation ofAGS cells of each group cultured for 0, 24, 48, 72, 96, 120 and 144 h, and flow cytometry was used to analyze the cell cycle and apoptosis in each group. The relationship between DKK1 and clinicopathological features of gastric cancer was analyzed after searching HPA database. Results：The gastric cancer AGS cells with stable DKK1 gene knockdown was successfully established, and it was confirmed that the mRNA and proteinexpressions of DKK1 in DKK1-shRNA group decreased by 72% and 47%, respectively, compared to shNC group (all P<0.05). The cell proliferation curve showed that, the cell proliferation in DKKl-shRNAgroup significantly decreased after 72 hour of culture compared with that in control and shNC groups (P<0.05). The cell number of S phase decreased from 32.06% to 25.87%, while the number of G2/M phase increased from 8.49% to 21.26% compared with shNC group (all P<0.05). The number of apoptotic cells also statistically increased from 10.34% to 20.65% (all P<0.05). The data of HPAdatabase showed that DKK1 mRNAlevel in gastric cancer tissues was significantly higher than that in normal tissues, and the high expression of DKK1 mRNAwas negatively correlat ed with the survival rate of gastric cancer patients. Conclusion: : Silencing DKK1 gene can inhibit the proliferation of gastric cancer cells, arrest cells in G2/M phase and promote cell apoptosis. DKK1 plays a pro-carcinogenic effect in gastric cancer.

Diagnostic value of combined serum AFP,TK1 and DKK1 levels in primary liver cancer / 国际检验医学杂志

Objective To investigate the diagnostic value of combined detection of serum alpha fetoprotein (AFP),thymidine kinase 1(TK1)and secreted protein Dickkopf-1(DKK1)in patients with primary liver cancer(PHC).Methods 85 patients with PHC admitted to the hospital from August 2015 to October 2016 were selected as PHC group,and 73 patients with benign liver disease as benign liver disease group,and 80 ca-ses healthy subjects as the control group.The serum levels of AFP,TK1 and DKK1 were detected in three groups,and the differences in each group were compored,and the diagnostic sensitivity,specificity,positive predictive value,negative predictive value and accuracy were calcuated.The diagnostic value of each index was analyzed by logistic regression.Results The serum AFP,TK1 and DKK1 levels in PHC group were signifi-cantly higher than those in benign liver disease group and control group(P<0.05),the serum AFP TK1 and DKK1 levles in benign liver disease group were significantly higher than those in the control group(P<0.05);the sensitivity,accuracy and negative predictive value of AFP + TK1+ DKK1 joint detection were sig-nificantly higher than that in the single index detection(P<0.05);Logistic regression analysis showed that AFP,TK1 and DKK1 were closely correlated with the diagnosis of PHC(P<0.05).Conclusion The com-bined detection of serum AFP,TK1 and DKK1 can significantly improve PHC positive diagnosis rate,which is of great significance for clinical early diagnosis and effective treatment,and is worth popularizing.

Increased Expression of Dickkopf-1 in Acral Lentiginous Melanoma / 대한피부과학회지

BACKGROUND: Dickkopf-1 (DKK-1), an inhibitor of the Wnt signaling pathway, is known as an inhibitor of melanocyte proliferation. In recent studies, the expression of DKK-1 gene is reduced in melanoma and they lose their preventive role during development or progression of melanoma. There are no available data regarding the changes in DKK-1 gene expression in acral lentiginous melanoma (ALM), which is common in Asians. OBJECTIVE: To analyze changes in DKK-1 expression in the development or progression of ALM in Koreans. METHODS: Immunohistochemical staining using DKK-1 antibody of 13 invasive ALM, six ALM in situ, nine acral nevi, and four benign non-related palmoplantar specimens as controls were evaluated by the semi-quantitative grading scale, which is divided into three distinctive grades according to the degree of cytoplasmic staining of DKK-1. RESULTS: Among the invasive ALM specimens, seven of 13 (53.8%) were graded as strongly positive (2+), and only one case (7.7%) was negative. In cases of ALM in situ, two specimens (33.3%) stained positive (1+) and the remaining four specimens (66.6%) were not stained. All specimens from both acral nevus and benign palmoplantar lesions, which were used as the control group, were also negative. CONCLUSION: In contrast with recent reports, DKK-1 expression showed a positive correlation with ALM progression or invasiveness. The role of DKK-1 as a potential predictor of ALM progression warrants further study.

Effect of ERRα in silencing DKK1 and SOST recombinant adenovirus vector-transfected MG63 Cells and bone-related proteins / 医学研究生学报

Objective WNT signaling pathway plays an important role in the formation, differentiation and maturation of bone cells, it is a classical intracellular signaling pathway involved in bone metabolism. DKK1 and Sost play a negative regulatory role in regulating bone mass and osteoblast differentiation, and are negative regulators of WNT signaling pathway. Estrogen-related receptor alpha (ERRα) regulates the functional activity of osteoblasts. The aim of study was to investigate the effect of ERRα on the transfection of MG63 cells and related proteins by the WNT signaling pathway inhibitor Dickkopf (DKK)1 and sclerostin (SOST) adenovirus vectors.Methods The cultured MG63 cells were divided into blank control group, silencing DKK1 group, silencing SOST group, silencing (DKK1+SOST) group, ERRα intervention empty adenovirus group, ERRα intervention silencing DKK1 group, ERRα intervention silencing SOST group, ERRα intervention silencing (DKK1+SOST) group. MG63 cells were transfected with packaged silencing DKK1 and SOST adenovirus vectors according to different groups. The activity of MG63 cells was detected by MTT assay, the activity of ALP was detected by alkaline phosphatase kit, and the concentration of calcium ion was analyzed by flow cytometry. Western blot was used to detect the expressions of low density lipoprotein associated protein 5 (LRP5), bone morphogenetic protein 2 (BMP2), osteopontin (OPN), osteoprotegerin(OPG).Results (1) Compared with blank control group, silencing DKK1, SOST, DKK1+SOST group and ERRα overexpression in the empty adenovirus group could increase cell activity, ALP activity, and decrease calcium ion concentration and increase the expressions of LRP5, BMP2, OPN, and OPG. Differences between groups were statistically significant(P0.05).Conclusion ERRα Overexpression can increase the activity of MG63 cells, ALP activity, LRP5, BMP2, OPN, and OPG proteins, and decrease the calcium ion concentration in silencing DKK1 and SOST adenovirus-transfected cells.

Diagnostic potential of Dickkopf-1 for heptocellular carcinoma using magnetic solid phase chemiluminescent immunoassay / 国际检验医学杂志

Objective This is the first study to explore clinical application value of serum Dickkopf-1 (DKK-1) detection in diagnosis of heptocellular carcinoma (HCC) by magnetic solid phase chemiluminescent immunoassay.Methods The level of serum DKK-1 and AFP in 205 cases of HCC,40 cases of liver cirrhosis,and 200 cases of healthy control were quantitatively detected by Magnetic solid phase chemiluminescent immunoassay.The area under ROC curve,sensitivity and specificity of DKK-1 and AFP for diagnosing HCC were calculated.Results The serum level of DKK-1 in HCC group was significantly higher than those of the liver cirrhosis group and healthy control group (P<0.01).DKK-1 maintained diagnostic sensitivity for patients with HCC who were alpha-fetoprotein (AFP) negative (66.3%).ROC curves showed optimum diagnostic cut-off value was 2.4 ng/mL,area under curve (AUC) was 0.822 (95% CI:0.783-0.856),sensitivity 65.9%,and specificity 87.5%).Moreover,measurement of DKK1 and AFP together improved diagnostic accuracy for HCC versus all controls compared with either test alone [AUC 0.915,95%CI:0.886-0.940),sensitivity 81.5 %(P<0.05)].Conclusion Serum DKK-1 detection has an important clinical value for diagnosis of HCC,especially for HCC with AFP negative.The combined detection of serum DKK-1 and AFP can greatly increase sensitivity and accuracy for diagnosing HCC.

Research progress of Dickkopf-1 related tumor metastasis / 国际肿瘤学杂志

As a secreted glycoprotein,Dickkopf-1 (DKK1) is closely related to tumor metastasis,and it is highly or lowly expressed in tumor.The high expression of DKK1 promotes the metastasis of a variety of malignant tumors including liver cancer,gastric cancer,non-small cell lung cancer and breast cancer.Recent studies have found that DKK1 is inextricably bound up with the latent metastasis of tumor.

Clinical application of DKK-1,TFF3 and CA72-4 detection in diagnosis of gastric cancer / 国际检验医学杂志

Objective To explore the clinical application of DKK-1,TFF3 and CA72-4 detection in the diagnosis and treatment of gastric cancer.Methods Seventy-five cases(gastric cancer group) of gastric cancer admitted to our hospital from January 2013 to May 2015 were selected.Seventy cases of benign gastric disease(benign gastric disease group) and 70 persons undergoing the physical examination(healthy control group) were selected as the research subjects.The concentration of CA72-4 in each group was detected by the electrochemiluminescence analyzer.The serum DKK-1 and TFF3 levels in each group were detected by enzyme linked immunosorbent assay(ELISA).The receiver operating characteristic(ROC) curve was drawn for evaluating the diagnostic efficiency of each index in each group.The sensitivity,specificity,positive predictive rate and negative predictive rate of 3 indicators for diagnosing gastric cancer before operation were compared.The concentration change of various indexes after gastric cancer radical resection were compared..Results The concentrations of DKK-1,TFF3 and CA72-4 in the gastric cancer group were significantly higher than those in the benign gastric disease group and healthy control group,the difference was statistically significant(P<0.05).The area under ROC curve of DKK-1,TFF3 and CA72-4 were 0.876(95%CI 0.803-0.950),0.944 4(95%CI 0.894-0.975) and 0.818(95%CI 0.726-0.884) respectively.The sensitivity of CA72-4 was 78.6% and the specificity was 84.3%,the sensitivity of DKK-1 was 93.6% and the specificity was 87.1%,the sensitivity and specificity of TFF3 was 92.4% and 90.1% respectively.The concentrations of DKK-1,TFF3 and CA72-4 after radical resection in the gastric cancer group were significantly reduced,the difference was statistically significant compared with before treatment(P<0.05).Conclusion The detection of DKK-1,TFF3 and CA72-4 has a certain clinical value for the diagnosis of gastric cancer.The combined detection of these 3 indicators is conducive to improve the specificity and sensitivity of gastric cancer diagnosis.

Serum expression and clinical significance of Dickkopf-1 in patients with rheumatoid arthritis / 中国医师进修杂志

Objective To investigate the serum expressions and clinical significance of Dickkopf-1 in patients with rheumatoid arthritis (RA). Methods The clinical data of 139 patients with RA were retrospectively analyzed, including the disease history, tender joint count (TJC), swollen joint count (SJC), platelet, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), rheumatoid factor (RF), anti-nuclear antibody (ANA), antikeratin antibody (AKA), anti-perinuclear factor (APF), anti cyclic citrullinated peptide antibody (anti-CCP), Dickkopf-1 and radiological (X-ray) staging. The disease activity scale (DAS) was evaluated, and the ESR and CRP levels were included. The relationship between Dickkopf-1 and the clinical data of RA, DAS44 score was analyzed. Results The serum level of Dickkopf-1 in patients with RA was (2.70 ± 0.46) μg/L. There was no relationship between serum Dickkopf-1 level and gender, age, course of disease, CRP, platelet, ANA, AKA, APF, RF, radiological staging in patients with RA (P>0.05). The serum Dickkopf-1 level was significantly associated with TJC, SJC, ESR, DAS44-ESR score, DAS44-CRP score and anti-CCP (r = 0.200, 0.291, 0.178, 0.222, 0.199 and 0.278, P = 0.019, 0.001, 0.037, 0.009, 0.028 and 0.012). Conclusions The serum Dickkopf-1 expression level is closely related to the occurrence and development of RA. Dickkopf-1 may contribute to diagnose the disease activity in patients with RA.

Diagnostic Value of Serum GP73 Combined with Dickkopf-1 and AFP in Hepatocellular Carcinoma / 现代生物医学进展

Objective:To investigate the diagnostic value of serum GP73 combined with Dickkopf-1 and AFP in hepatocellular carcinoma.Methods:117 cases of hepatocellular carcinoma in our hospital were collected as hepatocellular carcinoma group,80 patients with hepatitis B virus as the hepatitis group,and randomly selected 80 healthy subjects as the control group from September 2014 to September 2016.The serums GP73,Dickkopf-1,AFP level of every group were detected by the enzyme-linked immunosorbent assay (ELISA),and the relationship between the GP73,Dickkopf-1,AFP between clinicopathological features were analyzed,the diagnostic value of GP73,Dickkopf-1 and AFP in hepatocellular carcinoma were analyzed.Results:The serums GP73,Dickkopf-1,AFP level of hepatocellular carcinoma group were higher than those of hepatitis group,control group,and the serum AFP level of hepatitis group was higher than that of control group,the difference was statistically significant (P＜0.05).The GP73,Dickkopf-1,AFP in patients with classification B～C were higher than those in classification A among the Child Pugh classification,the difference was statistically significant (P＜0.05).No statistical significance on difference of GP73,Dickkopf-1,AFP between different differentiation,tumor size,number of tumors was found (P＞0.05).The sensitivity,specificity,positice predictive value,negative predictive value,and accuracy of GP73+Dickkopf-1+AFP in the diagnosis of hepatocellular carcinoma were higher than those of GP73,Dickkopf-1,AFP respectively,the difference was statistically significant (P＜0.05).Conclusion:Serums GP73,Dickkopf-1,AFP in patients with hepatocellular carcinoma have high expression levels,combined with the three indicators can obviously improve the diagnostic value of hepatocellular carcinoma,which has clinically important reference value.

Diagnostic value of combined detection of serum DKK1 and EB virus VCA-IgA for nasopharyngeal car-cinoma / 国际肿瘤学杂志

Objective To explore the diagnostic value of the combined detection of serum Dickkopf-1 (DKK1 )and EB viral capsid antigen immunoglobulin A (VCA-IgA)in patients with nasopharyngeal carcinoma (NPC).Methods Serum levels of DKK1 and VCA-IgA were measured by enzyme-linked immunosorbent assay (ELISA)for the 80 patients with NPC and 65 normal controls.Receiver operating characteristic (ROC) curve was used to calculate the diagnostic value.Results The serum levels [M(QR )]of DKK1 in patients with NPC were significantly higher than those in normal controls [580.773 (429.1 46 )pg/ml vs.31 6.1 74 (252.965)pg/ml],with a significant difference (Z=4.846,P<0.000 1 ).ROC curves showed that the opti-mum diagnostic cutoff for serum DKK1 was 611.981 pg/ml,with an area under curve (AUC)of 0.734 (95%CI:0.654-0.81 5,50.0% sensitivity,96.9% specificity).Measurement of VCA-IgA demonstrated an AUC of 0.71 4 (95%CI:0.631-0.798,47.5% sensitivity,95.4% specificity).The combined detection of DKK1 and VCA-IgA demonstrated an AUC of 0.849 (95%CI:0.783-0.91 4,76.3%sensitivity,95.4%spe-cificity).For patients with early-stage NPC,the detection effect of combined detection of DKK1 and VCA-IgA was much better than that in normal controls,with a significant difference (χ2 =23.784,P <0.001 ). Conclusion Serum DKK1 has potential diagnostic value for NPC.Combined detection of DKK1 and VCA-IgA may aid the early diagnosis of NPC.

Dickkopf-1 silencing inhibits invasion and epithelial-mesenchymal transition in gastric carcinoma cells by down-regulating β-catenin / 中国病理生理杂志

AIM: To explore the expression of Dickkopf-1 (DKK1) in human gastric carcinoma cells, and the influences of DKK1 gene silencing on cell invasion.METHODS: The levels of DKK1 in the human gastric mucosa cell line GES-1 and gastric carcinoma cell lines MKN-45 and SGC-7901 were detected by real-time PCR and Western blot.DKK1 gene was silenced by RNA interference, which was verified by real-time PCR, Western blot and ELISA.The cell invasion ability was determined by Transwell assay, and the cell proliferation was inhibited by mitomycin C.The levels of E-cadherin, N-cadherin, vimentin and β-catenin were determined by real-time PCR and Western blot.RESULTS: The expression of DKK1 was significantly higher in MKN-45 cells and SGC-7901 cells than that in GES-1 cells, indicating that DKK1 expression was obviously increased in gastric carcinoma cells.After successful silencing of DKK1 gene in the MKN-45 cells and SGC-7901 cells, the cell invasion ability was markedly decreased in a time-dependent pattern with increased expression of E-cadherin and decreased expression of N-cadherin and vimentin, indicating that DKK1 silencing dramatically inhibited gastric carcinoma cell invasion and epithelial-mesenchymal transition (EMT).The introduction of exogenous recombinant DKK1 (rDKK1) demonstrated the promoting effect of DKK1 on gastric carcinoma cell invasion and EMT.In addition, the inhibitory effects of DKK1 silencing on gastric carcinoma cell invasion and EMT were fulfilled by down-regulating β-catenin.CONCLUSION: The expression of DKK1 is significantly increased in human gastric carcinoma cells.Silencing of DKK1 markedly inhibits gastric carcinoma cell invasion and EMT by down-regulating β-catenin.