SPOCK1 is a novel transforming growth factor-β target gene that regulates lung cancer cell epithelial-mesenchymal transition

Overexpression of SPARC correlates with poor prognosis in patients with cervical carcinoma and regulates cancer cell epithelial-mesenchymal transition

Secreted protein acidic and rich in cysteine (SPARC) is associated with the progression of numerous types of cancer. However, the role of SPARC in the progression of cervical cancer has not yet been adequately elucidated. In the current study, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and immunohistochemistry were employed to evaluate the mRNA and protein expression of SPARC in normal cervical tissue, cervical intraepithelial neoplasia (CIN) and cervical cancer. In addition, three epithelial-mesenchymal transition (EMT) markers (E-cadherin, N-cadherin and vimentin) were detected by immunohistochemistry in the same specimens, and an enzyme-linked immunosorbent assay was conducted to detect the serum levels of SPARC in patients with cervical neoplasia. In highly invasive subclones of human cervical carcinoma cells, HeLa-1 and SiHa-1, lentiviral transfections were performed and RT-qPCR and western blot were used to investigate the effects of downregulated EGF-containing fibulin-like extracellular matrix protein 1 on the expression of E-cadherin, N-cadherin and vimentin. The results revealed that, in cervical carcinoma tissue, SPARC expression was significantly upregulated in a manner that positively correlated with N-cadherin and vimentin expression, and negatively correlated with E-cadherin expression. SPARC overexpression and high serum levels were significantly associated with the progression of cervical cancer and adverse prognosis of cervical cancer patients. Downregulation of SPARC can markedly reduce the expression of N-cadherin and vimentin and increase the expression of E-cadherin. Thus, overexpression of SPARC is significantly associated with poor prognostic clinicopathological characteristics in cervical carcinoma, and may be important in EMT. The results of the current study suggest that SPARC may be a potential therapeutic option for individuals diagnosed with cervical carcinoma.

SPOCK1 is upregulated in recurrent glioblastoma and contributes to metastasis and Temozolomide resistance

OBJECTIVES

Glioblastoma multiforme (GBM) is the most aggressive brain tumour type in humans. Its poor prognosis is largely attributed to its invasiveness and high rate of recurrence. Recurring GBM is commonly resistant to chemotherapeutic drugs, making it specially difficult to treat. Recent studies have revealed that matricellular glycoprotein SPOCK1 to be upregulated in several cancer types and to be specifically expressed in invasive GBM, but not in other types of non-invasive brain tumour, which prompted us to study the mechanism of action of SPOCK1 in invasion, recurrence and drug resistance of GBM cells.

MATERIALS AND METHODS

SPOCK1 expression in GBM tissues was evaluated using qPCR, Western blotting and immunohistochemical staining. Cell migration was tested by the wound healing method and cell invasion was assessed using transwell plates with Matrigel coating. Western blotting was performed for E-cadherin, vimentin, N-cadherin, p-Akt and Akt. Cell viability was examined using the MTT assay.

RESULTS

We found that the expression of SPOCK1 was significantly upregulated in recurrent GBM. We also demonstrated that SPOCK1 positively regulated migration, invasion and EMT process of GBM cells. Furthermore, SPOCK1 mediated TMZ resistance in GBM, as knockdown of SPOCK1 expression in TMZ-resistant GBM cells substantially sensitized these cells to TMZ.

CONCLUSION

SPOCK1 results were positive and it mediated TMZ resistance in GBM. In addition, SPOCK1 regulated invasion and TMZ resistance in GBM cells via the Akt signalling pathway.

SPOCK1 Overexpression Confers a Poor Prognosis in Urothelial Carcinoma

Purpose:The majority deaths of cancer patients are related to metastasis, thus genes associated with cell motility interest us. SPOCK1 was elected by data mining and serial evaluation. In addition, SPOCK1 has been reported to be highly expressed in different human cancers and been related to adverse outcomes. Therefore, we validate its prognostic significance in urothelial carcinoma (UC).

Materials and Methods:Real-time RT-PCR assay was used to detect SPOCK1 transcript level in 27 urinary tract urothelial carcinoma (UTUC) and 27 urinary bladder urothelial carcinoma (UBUC) samples. Immunohistochemistry evaluated by H-score determined SPOCK1 expressions in 340 UTUCs and 295 UBUCs. The transcript and protein expression were correlated with clinicopathological features. Further evaluations of the prognostic significance of SPOCK1 for disease-specific survival (DSS) and metastasis-free survival (MeFS) were analyzed.

Results:The expressions of SPOCK1 in UC were higher than those in normal urothelium by immunohistochemistry. The statistical analysis of clinicopathologic characteristics and immunohistochemistry showed that the higher expression of SPOCK1 was correlated to pT status (P<0.001), lymph node metastasis (UTUC, P=0.006; UBUC, P=0.033), higher histological grade (UTUC, P<0.001; UBUC, P<0.001), vascular invasion (UTUC, P<0.001; UBUC, P<0.001), perineurial invasion (UTUC, P<0.001; UBUC, P=0.001) and frequent mitosis (UTUC, P<0.001; UBUC, P=0.001). The prognosis of SPOCK1 of UC showed high SPOCK1 expression had significantly worse DSS and MeFS.

Conclusions:The investigation demonstrated that the higher expression of SPOCK1 correlates with a poor prognosis in UC.

Recursive Random Lasso (RRLasso) for Identifying Anti-Cancer Drug Targets

Uncovering driver genes is crucial for understanding heterogeneity in cancer. L1-type regularization approaches have been widely used for uncovering cancer driver genes based on genome-scale data. Although the existing methods have been widely applied in the field of bioinformatics, they possess several drawbacks: subset size limitations, erroneous estimation results, multicollinearity, and heavy time consumption. We introduce a novel statistical strategy, called a Recursive Random Lasso (RRLasso), for high dimensional genomic data analysis and investigation of driver genes. For time-effective analysis, we consider a recursive bootstrap procedure in line with the random lasso. Furthermore, we introduce a parametric statistical test for driver gene selection based on bootstrap regression modeling results. The proposed RRLasso is not only rapid but performs well for high dimensional genomic data analysis. Monte Carlo simulations and analysis of the "Sanger Genomics of Drug Sensitivity in Cancer dataset from the Cancer Genome Project" show that the proposed RRLasso is an effective tool for high dimensional genomic data analysis. The proposed methods provide reliable and biologically relevant results for cancer driver gene selection.

Characterization of the Transcriptional Complexity of the Receptive and Pre-receptive Endometria of Dairy Goats

Endometrium receptivity is essential for successful embryo implantation in mammals. However, the lack of genetic information remains an obstacle to understanding the mechanisms underlying the development of a receptive endometrium from the pre-receptive phase in dairy goats. In this study, more than 4 billion high-quality reads were generated and de novo assembled into 102,441 unigenes; these unigenes were annotated using published databases. A total of 3,255 unigenes that were differentially expressed (DEGs) between the PE and RE were discovered in this study (P-values < 0.05). In addition, 76,729–77,102 putative SNPs and 12,837 SSRs were discovered in this study. Bioinformatics analysis of the DEGs revealed a number of biological processes and pathways that are potentially involved in the establishment of the RE, notably including the GO terms proteolysis, apoptosis, and cell adhesion and the KEGG pathways Cell cycle and extracellular matrix (ECM)-receptor interaction. We speculated that ADCY8, VCAN, SPOCK1, THBS1, and THBS2 may play important roles in the development of endometrial receptivity. The de novo assembly provided a good starting point and will serve as a valuable resource for further investigations into endometrium receptivity in dairy goats and future studies on the genomes of goats and other related mammals.

Up-regulation of SPOCK1 induces epithelial-mesenchymal transition and promotes migration and invasion in esophageal squamous cell carcinoma

Invasion and metastasis are the major causes of death in patients with esophageal squamous cell carcinoma (ESCC). Recent studies have confirmed that SPARC/osteonectin, cwcv and kazal-like domains proteoglycan 1 (SPOCK1) plays multiple roles in cancer progression. This study aims to explore the clinical characteristics of SPOCK1 in ESCC and its roles in the migration and invasion of ESCC cell lines. In this study, the up-regulation of SPOCK1 expression was frequently detected in primary ESCC tumor tissues compared with those in non-tumor tissues, which was significantly associated with tumor invasion (p = 0.004) and distant metastasis (p = 0.010). SPOCK1 was expressed at higher level in TE13 cells as compared to the low malignant Eca109 and TE1 cells. Overexpression of SPOCK1 in Eca109 cells decreased the expressions of epithelial marker E-cadherin and ZO-1, while increased mesenchymal marker Vimentin and N-cadherin levels. After ectopic expression of SPOCK1, Eca109 cells exhibited a morphological change from an epithelial cobblestone phenotype to an elongated fibroblastic phenotype, concomitant with cytoskeletal rearrangements and increased migration and invasion, suggesting that EMT occurs. While silencing SPOCK1 in TE13 cells had the opposite effects. These results suggest that up-regulation of SPOCK1 in ESCC induces EMT, thus promotes migration and invasion in ESCC cells.

SPOCK1 as a potential cancer prognostic marker promotes the proliferation and metastasis of gallbladder cancer cells by activating the PI3K/AKT pathway

Background

Gallbladder cancer (GBC) is a leading cause of cancer-related death worldwide, and its prognosis remains poor, with 5-year survival of approximately 5%. In this study, we analyzed the involvement of a novel proteoglycan, Sparc/osteonectin, cwcv, and kazal-like domains proteoglycan 1 (SPOCK1), in the tumor progression and prognosis of human GBC.

Methods

SPOCK1 expression levels were measured in fresh samples and stored specimens of GBC and adjacent nontumor tissues. The effect of SPOCK1 on cell growth, DNA replication, migration and invasion were explored by Cell Counting Kit-8, colony formation, EdU retention assay, wound healing, and transwell migration assays, flow cytometric analysis, western blotting, and in vivo tumorigenesis and metastasis in nude mice.

Results

SPOCK1 mRNA and protein levels were increased in human GBC tissues compared with those in nontumor tissues. Immunohistochemical analysis indicated that SPOCK1 levels were increased in tumors that became metastatic, compared with those that did not, which was significantly associated with histological differentiation and patients with shorter overall survival periods. Knockdown of SPOCK1 expression by lentivirus-mediated shRNA transduction resulted in significant inhibition of GBC cell growth, colony formation, DNA replication, and invasion in vitro. The knockdown cells also formed smaller xenografted tumors than control GBC cells in nude mice. Overexpression of SPOCK1 had the opposite effects. In addition, SPOCK1 promoted cancer cell migration and epithelial-mesenchymal transition by regulating the expression of relevant genes. We found that activation of the PI3K/Akt pathway was involved in the oncogenic functions of SPOCK1 in GBC.

Conclusions

SPOCK1 activates PI3K/Akt signaling to block apoptosis and promote proliferation and metastasis by GBC cells in vitro and in vivo. Levels of SPOCK1 increase with the progression of human GBC. SPOCK1 acts as an oncogene and may be a prognostic factor or therapeutic target for patients with GBC.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-014-0276-y) contains supplementary material, which is available to authorized users.