Liantang Wang

Oncogenic roles of astrocyte elevated gene-1 (AEG-1) in osteosarcoma progression and prognosis

Astrocyte elevated gene-1 (AEG-1) is overexpressed in several cancers and plays an important role in cancer progression. However, AEG-1 expression, biological function, and clinical significance in osteosarcoma have not been uncovered. Utilizing manipulated human osteosarcoma cell lines and osteosarcoma tissues, we found that increasing expression of AEG-1 enhanced osteosarcoma cell proliferation and invasion in vitro, and knockdown of AEG-1 significantly attenuated osteosarcoma cell malignancy. Moreover, AEG-1 was overexpressed in osteosarcoma tissues, and overexpression of AEG-1 was strongly associated with gender (p = 0.018), clinical stages (p < 0.001), classification (p < 0.001), metastasis (p = 0.013), differentiation (p < 0.001), and poor survival (p = 0.021). Mechanistic studies conducted in vitro and in vivo revealed that AEG-1-mediated carcinogenesis and invasiveness might be through upregulating MMP-2. Taken together, our data strongly suggest that AEG-1 plays a crucial role in osteosarcoma progression through MMP-2, and AEG-1 could be a useful biomarker for the prediction of osteosarcoma progression and prognosis.

Astrocyte elevated gene-1(AEG-1) induces epithelial-mesenchymal transition in lung cancer through activating Wnt/β-catenin signaling

BackgroundNon-small cell lung cancer (NSCLC) is a highly metastatic cancer with limited therapeutic options, so development of novel therapies that target NSCLC is needed. During the early stage of metastasis, the cancer cells undergo an epithelial-mesenchymal transition (EMT), a phase in which Wnt/β-catenin signaling is known to be involved. Simultaneously, AEG-1 has been demonstrated to activate Wnt-mediated signaling in some malignant tumors.MethodsHuman NSCLC cell lines and xenograft of NSCLC cells in nude mice were used to investigate the effects of AEG-1 on EMT. EMT or Wnt/β-catenin pathway-related proteins were characterized by western blot, immunofluorescence and immunohistochemistry.ResultsIn the present study, we demonstrated that astrocyte elevated gene-1(AEG-1) ectopic overexpression promoted EMT, which resulted from the down-regulation of E-cadherin and up-regulation of Vimentin in lung cancer cell lines and clinical lung cancer specimens. Using an orthotopic xenograft-mouse model, we also observed that AEG-1 overexpression in human carcinoma cells led to the development of multiple lymph node metastases and elevated mesenchymal markers such as Vimentin, which is a characteristic of cells in EMT. Furthermore, AEG-1 functioned as a critical protein in the regulation of EMT by directly targeting multiple positive regulators of the Wnt/β-catenin signaling cascade, including GSK-3β and CKIδ. Notably, overexpression of AEG-1 in metastatic cancer tissues was closely associated with poor survival of NSCLC patients.ConclusionsThese results reveal the critical role of AEG-1 in EMT and suggest that AEG-1 may be a prognostic biomarker and its targeted inhibition may be utilized as a novel therapy for NSCLC.

Aberrant methylation of genes in stool samples as diagnostic biomarkers for colorectal cancer or adenomas: A meta‐analysis

Background:  An increasing number of hypermethylated genes in stool samples have been reported as biomarkers for the detection of colorectal cancer (CRC) or adenomas. We aimed to comprehensively review and compare the evidence for feasibility of using these biomarkers for the detection of colorectal neoplasia.

Astrocyte elevated gene-1 (AEG-1) promotes osteosarcoma cell invasion through the JNK/c-Jun/MMP-2 pathway

Osteosarcoma is the most common primary malignant bone tumour in children and adolescents and is characterised by high malignant and metastatic potentials. However, the molecular mechanism underlying this invasiveness remains unclear. In this study, we determined that PD98059 and SP600125, the two mitogen-activated protein kinase (MAPK) family inhibitors, decreased the osteosarcoma cell U2OS-AEG-1 migration and invasion that was enhanced by astrocyte elevated gene-1 (AEG-1) in an in vitro wound-healing and Matrigel invasion assay independently of cell viability. These findings indicate that AEG-1 promoted osteosarcoma cell invasion is relevant to the MAPK pathways. The up-regulation of AEG-1 increased the levels of phosphor-c-Jun N-terminal kinase (JNK) and phosphor-c-Jun; however, there were no marked changes in the levels of phosphor-extracellular regulated kinase (ERK) 1/2 or phosphor-c-Fos due to the activation of AEG-1 in U2OS. SP600125 (a JNK inhibitor) decreased phosphor-c-Jun and MMP-2 in U2OS-AEG-1, while PD98059 (a ERK1/2 inhibitor) had no influence on the levels of phosphor-c-Jun or MMP-2 in U2OS-AEG-1. Further study revealed that the down-regulation of phosphor-c-Jun not only obviously decreased the MMP-2 protein level and the MMP-2 transcriptional activity that were up-regulated by AEG-1 in Western-blot and luciferase reporter assays, but also inhibited the migration and invasion abilities of the U2OS-AEG-1 cells, which suggests that AEG-1 mediated U2OS invasion at least partially via the JNK/c-Jun/MMP-2 pathway. Consistent with these observations, immunohistochemical (IHC) staining revealed that AEG-1 expression was associated with the protein levels of phosphor-c-Jun and MMP-2 in needle biopsy paraffin-embedded archival human osteosarcoma tissues. Taken together, our findings suggest that AEG-1 plays a crucial role in the aggressiveness of osteosarcoma via the JNK/c-Jun/MMP-2 pathway.

Overexpression of astrocyte-elevated gene-1 is closely correlated with poor prognosis in human non-small cell lung cancer and mediates its metastasis through up-regulation of matrix metalloproteinase-9 expression.

Expression of astrocyte-elevated gene-1, a novel oncoprotein, is elevated in multiple cancers and plays a vital role in tumor cell growth, invasion, angiogenesis, and progression to metastasis. However, the functional significance of astrocyte-elevated gene-1 in non-small cell lung cancer still remains unclear. Our present study showed that the markedly up-regulated expression of astrocyte-elevated gene-1 was observed in non-small cell lung cancer cell lines and tissues at the level of both transcription and translation. Simultaneously, ectopic expression or small interfering RNA silencing of astrocyte-elevated gene-1 markedly enhanced or inhibited the invasive ability of non-small cell lung cancer cells, respectively. At the molecular level, we also revealed that the function of astrocyte-elevated gene-1 in promoting metastasis was associated with the activation of matrix metalloproteinase-9 expression. Consistent with these observations, immunostaining analysis revealed a significant positive correlation between astrocyte-elevated gene-1 and matrix metalloproteinase-9. Moreover, subcutaneous xenografts of non-small cell lung cancer cells engineered to express astrocyte-elevated gene-1 were highly invasive compared with the parental cells and expressed a high level of matrix metalloproteinase-9. In archival non-small cell lung cancer specimens, high astrocyte-elevated gene-1 expression correlated significantly with clinical staging (P = .048), differentiation (P = .023), and lymph node metastasis (P = .032). The overall survival time in patients with high astrocyte-elevated gene-1 expression was notably shorter than that in patients with low astrocyte-elevated gene-1 expression (P < .001). Taken together, our results indicate that astrocyte-elevated gene-1 plays a crucial role in the carcinogenesis and aggressiveness of non-small cell lung cancer, promoting its metastasis by modulating matrix metalloproteinase-9 expression and leading to a poor clinical prognosis.

High expression of CTHRC1 promotes EMT of epithelial ovarian cancer (EOC) and is associated with poor prognosis

Collagen triple helix repeat-containing 1 (CTHRC1) is aberrantly overexpressed in multiple malignant tumors. However, the expression characteristics and function of CTHRC1 in epithelial ovarian cancer (EOC) remain unclear. We found that CTHRC1 expression was up-regulated in the paraffin-embedded EOC tissues compared to borderline or benign tumor tissues. CTHRC1 expression was positively correlated with tumor size (p = 0.008), menopause (p = 0.037), clinical stage (p = 0.002) and lymph node metastasis (p < 0.001) and was also an important prognostic factor for the overall survival of EOC patients, as revealed by Kaplan-Meier analysis. CTHRC1 increased the invasive capabilities of EOC cells in vitro by activating the Wnt/β-catenin signaling pathway. We showed that ectopic transfection of CTHRC1 in EOC cells up-regulated the expression of EMT markers such as N-cadherin and vimentin, and EMT-associated transcriptional factor Snail. Knockdown of CTHRC1 expression in EOC cells resulted in down-regulation of N-cadherin, vimentin, Snail and translocation of β-catenin. Collectively, CTHRC1 may promote EOC metastasis through the induction of EMT process and serve as a potential biomarker for prognosis as well as a target for therapy.

GOLPH3 overexpression is closely correlated with poor prognosis in human non-small cell lung cancer and mediates its metastasis through upregulating MMP-2 and MMP-9.

Background/Aims: Golgi phosphoprotein 3 (GOLPH3) is a newly reported oncogene that plays a significant role in regulating cell growth. Recent research has shown that overexpression of GOLPH3 is correlated with patient survival and M classification in breast cancer and other cancers. However, the mechanisms by which GOLPH3 contributes to metastasis in non-small cell lung cancer (NSCLC) have not been previously clarified and are therefore the focus of this work. Methods: Immunohistochemistry (IHC) and western blotting analysis were performed to assess the GOLPH3 protein level, small interfering RNA (siRNA) and transwell assays were conducted to investigate the role of GOLPH3 in migration and invasion, and real-time PCR was performed to estimate the level of GOLPH3 mRNA expression. Results: GOLPH3 was significantly correlated with clinicopathological variables, such as the clinical stage (P=0.012), T classification (P=0.002) and metastasis (M classification) (P=0.008), in NSCLC patients and was negatively correlated with the prognosis. Knockdown of GOLPH3 significantly suppressed the migratory and invasive ability of NSCLC cell lines and downregulated the enzyme activity and protein levels of MMP-2 and MMP-9. Conclusions: The expression level of GOLPH3 is correlated with metastasis and prognosis in NSCLC, and GOLPH3 mediates metastasis by regulating the protein levels of MMP-2 and MMP-9 in vitro.

Detecting ALK-rearrangement of CTC enriched by nanovelcro chip in advanced NSCLC patients

Circulating tumor cells (CTC) shows great prospect to realize precision medicine in cancer patients. We developed the NanoVelcro Chip integrating three functional mechanisms. NanoVelcro CTC capture efficiency was tested in advanced NSCLC. Further, ALK-rearrangement status was examined through fluorescent in situ hybridization in CTCs enriched by NanoVelcro. NanoVelcro system showed higher CTC-capture efficiency than CellSearch in advanced NSCLC. CTC counts obtained by both methods were positively correlated (r=0.45, p<0.05). Further, CTC counts enriched by NanoVelcro correlated to the pTNM stage but CellSearch. All ALK-positive patients had 3 or more ALK-rearranged CTC per mL of blood. Less than 3 ALK-rearranged CTC was detected in ALK-negative patients. NanoVelcro can detect the ALK-rearranged status with consistent sensitivity and specificity compared to biopsy test. Furthermore, the ALK-rearranged CTC ratio correlated to the pTNM stage in ALK-positive patients. Following up with CTC enumeration by NanoVelcro and CellSearch observed their variations in reflecting clinical response of crizotinib treatment. NanoVelcro provides a sensitive method for CTC counts and characterization in advanced NSCLC. ALK-rearrangement can be detected in CTCs collected from advanced NSCLC patients by NanoVelcro, facilitating diagnostic test and prognosis analysis, most importantly offering one noninvasive method for real-time monitoring of treatment reaction.

Deleted in pancreatic carcinoma locus 4/Smad4 participates in the regulation of apoptosis by affecting the Bcl-2/Bax balance in non-small cell lung cancer.

Deleted in pancreatic carcinoma locus 4 influences tumorigenesis and tumor progression by various mechanisms, including apoptosis. The aim of this study is to determine whether deleted in pancreatic carcinoma locus 4 participates in apoptosis in lung cancer and clarify its relationship with clinical parameters of non-small cell lung cancer. Immunohistochemical results revealed that the positive rate of deleted in pancreatic carcinoma locus 4 in normal tracheal-bronchial epithelium (89.5%, 17/19) was much higher than that in tumor tissues (63.5%, 33/52) (P < .05) and closely correlated with lymph node metastasis (P < .001). These results were further confirmed by Western blot analysis. Furthermore, deleted in pancreatic carcinoma locus 4 overexpression was inversely associated with Bcl-2 immunostaining (P < .01), and the apoptosis index in deleted in pancreatic carcinoma locus 4-positive carcinomas (8.65 +/- 1.46) was much higher than that in deleted in pancreatic carcinoma locus 4-negative carcinomas (2.12 +/- 0.04) (P < .05). The results of deleted in pancreatic carcinoma locus 4 small interfering RNA in A549 cells also showed that deleted in pancreatic carcinoma locus 4 could inhibit cell proliferation, decrease Bcl-2 mRNA and protein expression, and increase Bax messenger RNA and protein expression. These findings indicated that Deleted in pancreatic carcinoma locus 4 might be an important biomarker for malignant transformation and be involved in inducing apoptosis by modulating Bcl-2/Bax balance.

The clue of a possible etiology about spontaneous regression of hepatocellular carcinoma: a perspective on pathology

Spontaneous regression of hepatocellular carcinoma (HCC) is a rare event. However, only a few of the causes of cases of HCC spontaneous regression are clear. More cases are ambiguous. We report on a patient who had a spontaneous regression of HCC as detected by histological and immunohistochemical exam, and compared this case to 20 cases of non-specific HCC. In our case, we found that the odd phenomenon is that CD163+ macrophages are overactivated in surviving HCC, which is spontaneously regressing. Concomitantly, we cannot find a similar phenomenon in peritumoral liver tissue or non-specific HCC. According to our microscopical morphology and immunohistochemical study, we considered that a clue of a possible etiology about HCC spontaneous regression is that CD163+ macrophages are overactivated.