Yanbin Zhao

Angiotensin II type 1 receptor antagonists inhibit cell proliferation and angiogenesis in breast cancer.

Angiotensin II type 1 receptor (AT1R) promotes tumor invasion, migration, metastasis and angiogenesis. We explored the potential antitumor effects of AT1R antagonists in breast cancer. We found that angiotensin II promoted cell proliferation and upregulated the expression of vascular endothelial growth factor A (VEGF-A) in MCF-7 cells. Losartan downregulated the expression of VEGF-A in MCF-7 cells treated with angiotensin II. Candesartan downregulated the expression of VEGF-A in mice bearing MCF-7 xenografts and inhibited tumor growth and angiogenesis. AT1R and VEGF-A expression correlated with increased microvascular density in 102 breast cancer patients. Our data suggest that AT1R antagonists might be useful to suppress breast cancer by inhibiting the angiotensin II.

Angiotensin II/angiotensin II type I receptor (AT1R) signaling promotes MCF-7 breast cancer cells survival via PI3-kinase/Akt pathway.

Angiotensin II (Ang II) is a bioactive peptide of the renin–angiotensin system, acting not only as a vasoconstrictor but also as a growth promoter via angiotensin II type 1 receptor (AT1R) in some cancer. In this study, we examined the mechanisms by which Ang II affected the cell proliferation in AT1R‐positive MCF‐7 human breast cancer cells. Ang II stimulated the growth of breast cancer cells in a dose‐ and time‐dependent manner. The maximal proliferation effect on MCF‐7 cells was obtained with 10−4 M Ang II at 24 h. Losartan (10−5 M, an AT1R antagonist) significantly decreased the level of Ang‐II‐induced proliferative effects, whereas PD123319 (10−5 M, an AT2R antagonist) had no effects. Moreover, Ang II could significantly accelerate S‐phase progression, which was inhibited by losartan (10−5 M) or LY294002 (50 µM, a PI3‐kinase inhibitor). In addition, Ang II caused rapid activation of p‐Akt in a dose‐ and time‐dependent manner. 10−4 M Ang II induced a significant increase of p‐Akt in 15 min. The peak level of p‐Akt could be persisted for at least 6 h. Among the signaling molecules downstream of Akt, we revealed that Ang II also significantly upregulated CyclinD1, GSK3β, and downregulated p27. Pretreatment with losartan (10−5 M) or LY294002 (50 µM) could significantly suppress these effects of Ang II. These findings suggest that Ang II plays a role in the growth of AT1R‐positive breast cancer cells through PI3‐kinase/Akt pathway activation. Therefore, targeting Ang II/AT1R signaling could be a novel therapeutic for breast cancer. J. Cell. Physiol. 225: 168–173, 2010.

Prognostic values of osteopontin-c, E-cadherin and β-catenin in breast cancer

OBJECTIVE To determine the correlation of cell adhesion molecules (osteopontin-c, E-cadherin and β-catenin) with clinicopathological characteristics in breast cancer. METHODS Immunostaining of osteopontin-c, E-cadherin and β-catenin were conducted in 170 samples of breast cancer and 30 samples of adjacent normal breast tissues. The correlation of osteopontin-c, E-cadherin and β-catenin expression level with clinicopathological characteristics was evaluated by Pearsons chi-square and Wilcoxon rank-sum test. Univariate and multivariate Cox hazard regression model was used to assess the prognostic values of osteopontin-c, E-cadherin and β-catenin in clinical outcome of breast cancer. RESULTS A higher level of osteopontin-c whereas lower levels of E-cadherin and β-catenin were observed in breast cancer as compared with the normal breast tissues. The expression of osteopontin-c was negatively associated with the expression of E-cadherin and β-catenin. The expression of osteopontin-c correlated with lymph node metastasis, and advanced TNM stage and histologic grade. The expression of E-cadherin correlated with low histologic grade; and β-catenin with low TNM stage and histological grade. Moreover, high osteopontin-c level correlated with tumor recurrence or metastasis as well as triple negative subtype. The expression of osteopontin-c was an independent prognostic factor for both disease-free and overall survival of breast cancer patients. CONCLUSION The data suggest that the expression of osteopontin-c could serve as a prognostic factor of breast cancer.

Ang II–AT1R Increases Cell Migration Through PI3K/AKT and NF‐κB Pathways in Breast Cancer

Angiotensin II (Ang II), a biologically active peptide of the renin–angiotensin system (RAS), plays an important role in promoting cell migration via Angiotensin II type 1 receptor (AT1R). In this study, we examined the mechanisms by which Ang II affected cell migration in AT1R‐positive MDA‐MB‐231 human breast cancer cells. Ang II increased cell migration and expression of matrix metalloproteinase (MMP)‐2,‐9 in a dose‐dependent manner. Ang II‐mediated cell migration was reduced by specific blocking of MMP‐2 and MMP‐9, as well as with pretreatment with inhibitors of AT1R, phosphatidylinositol 3‐kinase (PI3K), Akt, and NF‐κB. Similarly, Ang II‐mediated expression of MMP‐2,‐9 was downregulated by pretreatment with inhibitors of AT1R and PI3K. In addition, Ang II treatment significantly induced phosphorylation of PI3K, Akt, and resulted in increased NF‐κB activity. These findings suggest that Ang II activates the AT1R/PI3K/Akt pathway, which further activates IKKα/β and NF‐κB, resulting in enhanced expression of MMP‐2,‐9 and migration in human breast cancer cells. Therefore, targeting Ang II/AT1R/PI3K/Akt/NF‐κB signaling could be a novel anti‐metastatic therapy for breast cancer. J. Cell. Physiol. 229: 1855–1862, 2014.

MiR-181b regulates cisplatin chemosensitivity and metastasis by targeting TGFβR1/Smad signaling pathway in NSCLC

MicroRNAs (miRNAs) have been identified as important post-transcriptional regulators involved in various biological and pathological processes of cells, but their underlying mechanisms in chemosensitivity and metastasis have not been fully elucidated. The objective of this study was to identify miR-181b and its mechanism in the chemosensitivity and metastasis of NSCLC. We found that miR-181b expression levels were lower in A549/DDP cells compared with A549 cells. Functional assays showed that the overexpression of miR-181b inhibited proliferation, enhanced chemosensitivity to DDP, attenuated migration and metastatic ability in NSCLC cell lines in vitro and in vivo. TGFβR1 was subsequently identified as a novel functional target of miR-181b. TGFβR1 knockdown revealed similar effects as that of ectopic miR-181b expression, whereas overexpression of TGFβR1 rescued the function of miR-181b-mediated growth, chemosensitivity and metastasis in NSCLC cells. In addition, miR-181b could inactivate the TGFβR1/Smad signaling pathway. We also observed that decreased miR-181b expression and increased TGFβR1 expression were significantly associated with chemosensitivity to DDP and tumor metastasis in NSCLC patients. Consequently, miR-181b functions as a tumor suppressor and has an important role in proliferation, chemosensitivity to DDP and metastasis of NSCLC by targeting TGFβR1/Smad signaling pathway.

ABCC3 as a marker for multidrug resistance in non-small cell lung cancer

Multidrug resistance (MDR) contributes to the failure of chemotherapy and high mortality in non-small cell lung cancer (NSCLC). We aim to identify MDR genes that predict tumor response to chemotherapy. 199 NSCLC fresh tissue samples were tested for chemosensitivity by MTT assay. cDNA microarray was done with 5 samples with highest resistance and 6 samples with highest sensitivity. Expression of ABCC3 mRNA and protein was detected by real-time PCR and immunohistochemisty, respectively. The association between gene expression and overall survival (OS) was examined using Cox proportional hazard regression. 44 genes were upregulated and 168 downregulated in the chemotherapy-resistant group. ABCC3 was one of the most up-regulated genes in the resistant group. ABCC3-positive expression correlated with lymph node involvement, advanced TNM stage, more malignant histological type, multiple-resistance to anti-cancer drugs, and reduced OS. ABCC3 expression may serve as a marker for MDR and predictor for poor clinical outcome of NSCLC.

miRNA-378 reverses chemoresistance to cisplatin in lung adenocarcinoma cells by targeting secreted clusterin

Cisplatin resistance is a major obstacle in the treatment of NSCLC, and its mechanism has not been fully elucidated. The objectives of the study were to determine the role of miR-378 in the sensitivity of lung adenocarcinoma cells to cisplatin (cDDP) and its working mechanism. With TargetScan and luciferase assay, miR-378 was found to directly target sCLU. miR-378 and sCLU were regulated in A549/cDDP and Anip973/cDDP cells to investigate the effect of miR-378 on the sensitivity and apoptotic effects of cDDP. The effect of miR-378 upregulation on tumor growth was analyzed in a nude mouse xenograft model. The correlation between miR-378 and chemoresistance was tested in patient samples. We found that upregulation of miR-378 in A549/cDDP and Anip973/cDDP cells significantly down-regulated sCLU expression, and sensitized these cells to cDDP. miR-378 overexpression inhibited tumor growth and sCLU expression in a xenograft animal model. Analysis of human lung adenocarcinoma tissues revealed that the cDDP sensitive group expressed higher levels of miR-378 and lower levels of sCLU. miR-378 and sCLU were negatively correlated. To conclude, we identified sCLU as a novel miR-378 target, and we showed that targeting sCLU via miR-378 may help disable the chemoresistance against cisplatin in lung adenocarcinoma cells.

USP22 promotes tumor progression and induces epithelial–mesenchymal transition in lung adenocarcinoma

OBJECTIVES Our previous study showed that USP22 as an oncogene may mediate cancer development and progression in NSCLC, but the underlying molecular mechanism remains uncharacterized. Epithelial-mesenchymal transition (EMT) has been reported to play an important role in migration and invasion of the tumor cells. Thus, this study aims to determine the clinical significance and the possible roles of USP22 in EMT and progression of lung adenocarcinoma. METHODS Immunohistochemistry was used to determine the expression of USP22 in clinical samples. The clinical correlations and prognostic significance of the aberrantly expressed proteins were evaluated by statistical analysis. Moreover, we evaluated whether USP22 could induce EMT in cultured lung cancer cells. RESULTS The USP22 expression was positive in 76.03% of specimens and was correlated with advanced clinicopathologic classifications (differentiation, T and AJCC stages) and TGF-β1 expression (p=0.008). Multivariate Cox regression analysis revealed that USP22 expression level was an independent prognostic factor for both overall survival and disease-free survival (HR, 2.060; p=0.013 and HR, 1.993; p=0.016). In vitro study revealed that USP22 can regulate proliferation and invasive properties, and induce EMT of lung adenocarcinoma cells. Moreover, USP22 may up-regulate TGF-β1 expression. CONCLUSIONS Our data indicated that USP22 may promote lung adenocarcinoma cell invasion by the induction of EMT.

Baseline staging tests based on molecular subtype is necessary for newly diagnosed breast cancer

BackgroundBone scanning (BS), liver ultrasonography (LUS), and chest radiography (CXR) are commonly recommended for baseline staging in patients with newly diagnosed breast cancer. The purpose of this study is to demonstrate whether these tests are indicated for specific patient subpopulation based on clinical staging and molecular subtype.MethodsA retrospective study on 5406 patients with newly diagnosed breast cancer was conducted to identify differences in occurrence of metastasis based on clinical staging and molecular subtypes. All patients had been evaluated by BS, LUS and CXR at diagnosis.ResultsComplete information on clinical staging was available in 5184 patients. For stage I, II, and III, bone metastasis rate was 0%, 0.6% and 2.7%, respectively (P < 0.01); liver metastasis rate was 0%, 0.1%, and 1.0%, respectively (P < 0.01); lung metastasis rate was 0.1%, 0.1%, and 0.7%, respectively (P < 0.01). Complete information on molecular subtype was available in 3411 patients. For Luminal A, Luminal B (HER2-), Luminal BH (HER2+), HER2+ overexpression, and Basal-like, bone metastasis rate was 1.4%, 0.7%, 2.5%, 2.7%, and 0.9%, respectively (P < 0.05); liver metastasis rate was 0.1%, 0.1%, 1.0%, 1.1%, and 0.9%, respectively (P < 0.01); lung metastasis rate was 0.20%, 0%, 0%, 0.27%, and 0.9%, respectively (P < 0.05). cT (tumor size), cN (lymph node), PR (progesterone receptor), and HER2 status predicted bone metastasis (P < 0.05). cT, cN, ER (estrogen receptor), PR, and HER2 status predicted liver metastasis (P < 0.05). cT, cN, and PR status predicted lung metastasis (P < 0.05).ConclusionThese data indicate that based on clinical staging and molecular subtypes, BS, LUS and CXR are necessary for patients with newly diagnosed breast cancer.

TRIM44 promotes proliferation and metastasis in non-small cell lung cancer via mTOR signaling pathway

Tripartite motif-containing protein 44 (TRIM44) was recently identified as a potential therapeutic target in several types of malignancy, but its effect on the clinical course of malignancy and its underlying regulatory mechanism remain largely unknown. The present study shows that upregulation of TRIM44 is associated with poor differentiation, advanced pTNM stage, adenocarcinoma subtype, lymph node metastasis and, most importantly, unfavorable survival in patients with non-small cell lung cancer (NSCLC). TRIM44 knockdown inhibited the invasion and migration of human NSCLC cells, which was concurrent with downregulation of mesenchymal markers and upregulation of epithelial markers. Overexpression of TRIM44 induced the epithelial-to-mesenchymal transition (EMT) and increased the metastatic potential of lung cancer cells. Additionally, TRIM44 induced cell proliferation in vitro and tumor growth in vivo by accelerating G1/S transition via upregulation of cyclins and CDKs. TRIM44-induced mTOR signaling, EMT, and cyclin/CDK upregulation were reversed by treatment with a mammalian target of rapamycin (mTOR) inhibitor. These results provide a model for the relationship between TRIM44 expression and lung cancer progression, and open up new avenues for the prognosis and therapy of lung cancer.