Tinghua Hu

SDF-1/CXCR4 promotes epithelial-mesenchymal transition and progression of colorectal cancer by activation of the Wnt/β-catenin signaling pathway.

Stromal cell-derived factor 1 (SDF-1) and its receptor, CXCR4, play an important role in angiogenesis and are associated with tumor progression. This study aimed to investigate the role of SDF-1/CXCR4-mediated epithelial-mesenchymal transition (EMT) and the progression of colorectal cancer (CRC) as well as the underlying mechanisms. The data showed that expression of CXCR4 and β-catenin mRNA and protein was significantly higher in CRC tissues than in distant normal tissues. CXCR4 expression was associated with β-catenin expression in CRC tissues, whereas high CXCR4 expression was strongly associated with low E-cadherin, high N-cadherin, and high vimentin expression, suggesting a cross talk between the SDF-1/CXCR4 axis and Wnt/β-catenin signaling pathway in CRC. In vitro, SDF-1 induced CXCR4-positive colorectal cancer cell invasion and EMT by activation of the Wnt/β-catenin signaling pathway. In contrast, SDF-1/CXCR4 axis activation-induced colorectal cancer invasion and EMT was effectively inhibited by the Wnt signaling pathway inhibitor Dickkopf-1. In conclusion, CXCR4-promoted CRC progression and EMT were regulated by the Wnt/β-catenin signaling pathway. Thus, targeting of the SDF-1/CXCR4 axis could have clinical applications in suppressing CRC progression.

Clinicopathologic significance of CXCR4 and Nrf2 in colorectal cancer.

The CXCR4 and Nrf2 signaling pathways are abnormally activated in response to cellular stress in various types of human cancers. In this study, we examined the expression of CXCR4 and Nrf2 in colorectal cancer (CRC) tissue specimens and investigated their correlation with patient clinicopathologic characteristics. We determined CXCR4 and Nrf2 expression in 76 CRC tissue specimens and paired normal tissue specimens by immunohistochemistry and real-time PCR. We found that the protein and mRNA transcript levels of CXCR4 were significantly higher in CRC tissue specimens than in paired normal tissues, while the expressions of Nrf2 protein and mRNA were increased in CRC tissues compared to distant non-cancerous tissues. High expression level of CXCR4 was positively correlated with poorly differentiated (P = 0.031), more advanced tumor-node-metastasis (TNM) stage (P = 0.019), lymph node metastasis (P = 0.007) and distant metastasis (P = 0.018). However, the expression of Nrf2 protein was positively correlated with larger tumor size (P = 0.049), more advanced TNM stage (P = 0.013), lymph node metastasis (P = 0.016) and distant metastasis (P = 0.023). Moreover, there was a strong relationship between CXCR4 and Nrf2 expression in CRC tissues, indicating that high Nrf2 expression may contribute to CXCR4 overexpression. In addition, combined expression of CXCR4 and Nrf2 strongly correlated with lymph node metastasis and distant metastasis (P = 0.003). Furthermore, we found that combined high expression of CXCR4 and Nrf2 had stronger correlation with lymph node metastasis and distant metastasis than any single molecule did. This study indicated that the abnormal expression of CXCR4 and Nrf2 contributed to the progression of CRC.

Knockdown of Lymphoid Enhancer factor 1 Inhibits Colon Cancer Progression In Vitro and In Vivo

Expression of lymphoid enhancer factor 1 (LEF1) is frequently altered in different human cancers. This study aimed to assess LEF1 expression in colon cancer tissues and to explore changed phenotypes, gene expressions, and the possible mechanism after knocked down LEF1 expression in colon cancer cell lines. A total of 106 colon cancer and matched paratumorous normal tissues were used to assess LEF1 expression using immunohistochemistry and qRT-PCR. LEF1 lentivirus was used to knockdown LEF1 expression for the assessment of cell viability, cell cycle distribution, apoptosis, and gene expressions. The nude mouse xenograft assay was performed to detect the effects of LEF1 knockdown in vivo. The data showed that the levels of LEF1 mRNA and protein were significantly increased in human colon cancer tissues compared to the matched paratumorous normal tissues and were associated with infiltration depth, lymph node and distant metastases, advanced TNM (tumor-node-metastasis) stages, and shorter overall survival. Furthermore, LEF1 knockdown reduced tumor cell viability, invasion capacity, MMP2 and MMP-9 expression, but induced apoptosis. Nude mouse xenograft assay showed that LEF1 knockdown suppressed tumor formation and growth in vivo. In addition, the expression of Notch pathway-related proteins RBP-jκ and Hes1 was reduced in LEF1 knockdown cells. Taken together, LEF1 protein was overexpressed in colon cancer tissues and knockdown of LEF1 expression inhibited colon cancer growth in vitro and in vivo. These data suggest that targeting of LEF1 expression should be further evaluated for colon cancer prevention and therapy.

Loss of p57 expression and RhoA overexpression are associated with poor survival of patients with hepatocellular carcinoma

p57 and Ras homology A (RhoA) have been implicated in the growth and metastasis of several types of human cancers. This study aimed to detect their expression in hepatocellular carcinoma (HCC) tissue specimens and to determine a possible association with clinicopathological data and patient survival. A total of 80 HCC and corresponding distant normal tissue specimens were processed for immunohistochemical and qPCR analyses of p57 and RhoA expression. The data showed that expression of p57 mRNA and protein was reduced in HCC tissues when compared to that in distant non-cancer tissues (P<0.05), while expression of RhoA mRNA and protein was significantly higher in HCC tissue specimens when compared to that of the distant normal tissues. Loss of p57 expression was associated with HCC with higher α-fetoprotein (AFP) levels (>400 ng/ml; P=0.044), larger tumor size (>5 cm, P=0.004), poor tumor differentiation (P=0.020), advanced TNM stage (P=0.027), capsule invasion (P=0.018) and tumor thrombosis (P=0.008), whereas expression of RhoA protein was significantly associated with poor tumor differentiation (P=0.042), capsule invasion (P=0.022), and tumor thrombosis (P=0.002). Furthermore, there was a strong inverse relationship between p57 and RhoA expression in HCC tissues, indicating that loss of p57 expression may contribute to RhoA overexpression in HCC tissues. The median survival time of HCC patients with p57+ and p57- expression was 13.0 and 9.0 months, respectively, whereas the median survival time of HCC patients with RhoA+ and RhoA- was 9.0 and 15.0 months. Univariate analysis revealed that the levels of AFP, tumor size, TNM stage, histological grade, capsule invasion, tumor thrombosis, p57, RhoA and co-expression of p57 and RhoA were all significant prognostic indicators for overall survival of HCC patients. Multivariate analysis showed that tumor size, TNM stage, p57, RhoA and combined loss of p57 with RhoA were risk factors for poor survival of HCC patients. This study indicates that the abnormal expression of p57 and RhoA contributes to progression of HCC and poor survival of patients.

Prognostic significance of co-expression of nm23 and p57 protein in hepatocellular carcinoma.

Aim:  To investigate the unbalance of proliferation and apoptosis and the functions of cell‐cycle proteins and apoptotic factor in metastasis of hepatocellular carcinoma (HCC) and their effect in prognosis.

Expression and significance of the novel tumor-suppressor gene SMG-1 in hepatocellular carcinoma

Recent studies have demonstrated that SMG-1, a newly characterized member of the family of phosphatidylinositol 3-kinase-related protein kinases (PIKKs), is involved in tumorigenesis as a new tumor suppressor. However, its expression and significance in hepatocellular carcinoma (HCC) remain obscure. The present study investigated SMG-1 expression in HCC tissue specimens, aimed at defining the association with clinicopathological significance. Both immunohistochemistry and qRT-PCR were employed to analyze SMG-1 expression in 157 HCC and corresponding distant normal tissue specimens. The results revealed that expression of SMG-1 was significantly lower in the HCC tissue specimens than that in the distant normal tissues. Moreover, a lower expression level of SMG-1 was significantly correlated with serum α-fetoprotein level (P=0.001), poorly differentiated tumors (P=0.009) and more advanced TNM stage (P<0.001). Further study showed that SMG-1 expression was exactly associated with tumor differentiation and clinical stage in HCC. Kaplan-Meier analysis indicated that low SMG-1 expression was related to poor overall survival, and the prognostic impact of SMG-1 was further confirmed by stratified survival analysis. Importantly, multivariate analysis revealed that low SMG-1 expression was an independent prognostic marker for an unfavorable overall survival. We conclude that SMG-1 is downregulated in HCC and may represent a promising biomarker for predicting the prognosis of HCC, including the prognosis of early-stage patients.

Nrf2 promotes progression of non-small cell lung cancer through activating autophagy

ABSTRACT The transcription factor, NFE2-related factor 2 (Nrf2) and autophagy have been implicated in the oxidative-stress response during tumor evolution. However, few studies focus on crosstalk between Nrf2 and autophagy in cancer progression of non-small cell lung cancer (NSCLC). Herein, we evaluated the effect of Nrf2 on autophagy in NSCLC and their role in development of NSCLC. Effect of Nrf2 on overal survival (OS) of NSCLC patients were evaluated. Cell biological behaviors in response to Nrf2 were evaluated by MTT, colony formation assay and flow cytometry. Effect of 3-MA (a classical inhibitor of autophagy) on 95D-Nrf2 cells was also analyzed using flow cytometry. After up/down-regulating Nrf2 in NSCLC cell lines, expression of autophagy-related proteins were evaluated with western blot analysis. The results revealed that Nrf2 was an independent prognositc factor negtively associated with OS of NSCLC patients. Elevated Nrf2 expression promotes NSCLC progression, enhancing the escape of tumor cells from apoptosis in vivo and in vitro. Double staining with Annexin V-APC and 7-AAD showed that the proportions of apoptotic cells in 95D-Nrf2 cells were gradually increased after the addition of 3-MA. Importently, Nrf2 induced autophagosome formation and enhanced autophagic activity, which subsequently inhibits NSCLC cell apoptosis. In conclusion, our present study demonstrates that Nrf2 promotes progression of non-small cell lung cancer through activating autophagy. It provides novel insights into Nrf2-mediated of cell proliferation in NSCLC and may facilitate therapeutic development against NSCLC.

Loss of Beclin1 expression and Nrf2 overexpression are associated with poor survival of patients with non-small cell lung cancer

BACKGROUND Nrf2 pathway and autophagy are abnormally activated in response to cellular stress in various types of human cancers. In this study, we selected Beclin1 as an enter point to discuss the relationship between Nrf2 pathway and autophagy, and defined their associations with clinic pathological features and survival of the patients. METHOD NSCLC specimens were processed for immunohistochemical and qRT-PCR to analyses the expression of Beclin1 and Nrf2. Kaplan-Meier method and log-rank test were used in the survival data. RESULTS Beclin1 protein level was found to be significantly associated with more advanced TNM stage (P = 0.035), lymph node metastasis (P = 0.017) and distant metastasis (P = 0.005). The expression of Nrf2 protein was associated with larger tumor size (P = 0.032), more advanced TNM stage (P = 0.011), lymph node metastasis (P = 0.045) and distant metastasis (P = 0.013). Beside there was a strong inverse relationship between Beclin1 and Nrf2 expression in the NSCLC tissues. Distant metastasis, Beclin1, Nrf2, and Beclin1-/Nrf2+ expression was conformed to be independent prognostic factors of patients. CONCLUSION Both Nrf2 overexpression and Beclin1 lower-expression are independent indicators of a poor prognosis in NSCLC patients.

Combined Evaluation of Expression of CXCR4 and Nrf2 as Prognostic Factor for Patients with Gastric Carcinoma

BACKGROUND CXC Chemokine Receptor 4 (CXCR4) and NFE-related factor 2 (Nrf2) have been observed implicated with cell malignant behavior of human cancers. AIMS In this study, we detected their expression in gastric carcinoma (GC) tissue specimens and related the result with clinicopathological data and patient survival. METHODS 120 GC and compared normal tissue specimens were processed to analyse the expression of CXCR4 and Nrf2. We found that the expression of CXCR4 and Nrf2 was dramatically increased in GC tissues when compared to the distant non-cancer tissues (P<0.05). CXCR4 overexpression was associated with the depth of invasion (P= 0.006), Histological grade (P=0.018), TNMstage (P= 0.021), lymph node metastasis (P < 0.001) and distant metastasis (P=0.026), whereas overexpression of Nrf2 protein was significantly associated with tumor size (P=0.045), Histological grade (P=0.026), TNMstage (P= 0.020), lymph node metastases (P < 0.001) and distant metastasis (P=0.008). Furthermore, we observed a significant co-expression of CXCR4 and Nrf2 expression in GC specimens. RESULTS In the survival part, we found that GC patients with CXCR4+ and Nrf2+ had worse outcomes. The significant prognostic indicators are age, tumor size, histological grade, TNMstage, CXCR4, Nrf2, and coexpression of CXCR4 and Nrf2 in GC patients. Multivariate analysis showed that TNMstage and CXCR4+/Nrf2+ expression were risk factors. Above all we come to the conclusion that the expression of CXCR4 might partly be regulated by the level of Nrf2 and both positive expressions suggest poor prognosis of GC patients.