LASP-1 interacts with ErbB2 in ovarian cancer cells

LASP-1 was identified as a protein following mass spectrometric analysis of phosphoproteins consequent to signaling by ErbB2 in SKOV-3 cells. It has been previously identified as an oncogene and is located on chromosomal arm 17q 0.76Mb centromeric to ErbB2. It is expressed in serous ovarian cancer cell lines as a 40kDa protein. In SKOV-3 cells, it was phosphorylated and was inhibited by Lapatinib and CP7274714. LASP-1 co-immunoprecipitated with ErbB2 in SKOV-3 cells, suggesting a direct interaction. This interaction and phosphorylation were independent of the kinase activity of ErbB2. Moreover, the binding of LASP-1 to ErbB2 was independent of the tyrosine phosphorylation of LASP-1. LASP-1 was neither expressed on the surface epithelium of the normal ovary nor in the fallopian tube. It was expressed in 28% of ovarian tumours (n=101) that did not significantly correlate with other clinical factors. In tumours from patients with invasive ductal carcinoma of the breast who had ErbB2 amplification (3+), LASP-1 was expressed in 3/20 (p <0.001). Analysis of the expression of an independent dataset of ovarian and breast tumors from TCGA showed the significant co-occurrence of ErbB2 and LASP-1 (p<0.01). These results suggest that LASP-1 and ErbB2 interaction could be important in the pathogenesis of ovarian cancer.

Estimating the risk of malignancy of adnexal masses: validation of the ADNEX model in the hands of nonexpert ultrasonographers in a gynaecological oncology centre in China

Background This study aims to validate the diagnostic accuracy of the International Ovarian Tumor Analysis (IOTA) the Assessment of Different NEoplasias in the adneXa (ADNEX) model in the preoperative diagnosis of adnexal masses in the hands of nonexpert ultrasonographers in a gynaecological oncology centre in China. Methods This was a single oncology centre, retrospective diagnostic accuracy study of 620 patients. All patients underwent surgery, and the histopathological diagnosis was used as a reference standard. The masses were divided into five types according to the ADNEX model: benign ovarian tumours, borderline ovarian tumours (BOTs), stage I ovarian cancer (OC), stage II-IV OC and ovarian metastasis. Receiver operating characteristic (ROC) curve analysis was used to evaluate the ability of the ADNEX model to classify tumours into different histological types with and without cancer antigen 125 (CA 125) results. Results Of the 620 women, 402 (64.8%) had a benign ovarian tumour and 218 (35.2%) had a malignant ovarian tumour, including 86 (13.9%) with BOT, 75 (12.1%) with stage I OC, 53 (8.5%) with stage II-IV OC and 4 (0.6%) with ovarian metastasis. The AUC of the model to differentiate benign and malignant adnexal masses was 0.97 (95% CI, 0.96–0.98). Performance was excellent for the discrimination between benign and stage II-IV OC and between benign and ovarian metastasis, with AUCs of 0.99 (95% CI, 0.99–1.00) and 0.99 (95% CI, 0.98–1.00), respectively. The model was less effective at distinguishing between BOT and stage I OC and between BOT and ovarian metastasis, with AUCs of 0.54 (95% CI, 0.45–0.64) and 0.66 (95% CI, 0.56–0.77), respectively. When including CA125 in the model, the performance in discriminating between stage II–IV OC and stage I OC and between stage II–IV OC ovarian metastasis was improved (AUC increased from 0.88 to 0.94, P = 0.01, and from 0.86 to 0.97, p = 0.01). Conclusions The IOTA ADNEX model has excellent performance in differentiating benign and malignant adnexal masses in the hands of nonexpert ultrasonographers with limited experience in China. In classifying different subtypes of ovarian cancers, the model has difficulty differentiating BOTs from stage I OC and BOTs from ovarian metastases.

The Inhibitory Effect of KIAA1456 on the Proliferation and Metastasis of Epithelial Ovarian Cancer Through SSX1 and AKT Signaling Pathway

Background: KIAA1456 is effective in the inhibition of tumorigenesis. We previously confirmed that KIAA1456 inhibits cell proliferation and metastasis in epithelial ovarian tumours. In the current study, the specific molecular mechanisms and clinical significance of KIAA1456 underlying the repression of epithelial ovarian cancer were investigated.Methods: Immunohistochemistry was used to evaluate the protein expression of KIAA1456 and SSX1 in epithelial ovarian tumours and normal ovarian tissues. The relationship of KIAA1456 and SSX1 with overall survival of patients with epithelial ovarian cancer was analysed with Kaplan–Meier survival curve and log-rank tests. KIAA1456 was overexpressed and silenced in HO8910PM cells with a lentivirus. The anticancer activity of KIAA1456 was tested by CCK8, plate clone formation assay, flow cytometry, wound healing assay and Transwell invasion assay. Xenograft tumour models were used to investigate the effects of KIAA1456 on tumour growth in vivo. Bioinformatics analyses of microarray profiling indicated that SSX1 and the PI3K/AKT signalling pathway were differentially expressed in KIAA1456-overexpressing and control cells. Therefore, the biological function of HO8910PM cotransfected with KIAA1456- and SSX1-overexpressing cells was detected to validate the rescue effect of SSX1. The downstream factors of PI3K/AKT that are related to cell growth and apoptosis, including p-AKT, PCNA, MMP9, CyclinD1 and Bcl-2, were detected by Western blot analysis.Results: KIAA1456 expression was lower in epithelial ovarian tumours than in normal ovarian tissues. Its expression level negatively correlated with pathological grade. Pearson’s correlation analysis showed that KIAA1456 negatively correlated with SSX1 expression. The overexpression of KIAA1456 in HO8910PM cells inhibited proliferation, migration and invasion and promoted apoptosis. By contrast, the silencing of KIAA1456 resulted in the opposite behaviour. A xenograft tumour experiment showed that KIAA1456 overexpression inhibited tumour growth in vivo. Mechanistically, the overexpression of KIAA1456 inhibited SSX1 expression and AKT phosphorylation in HO8910PM cells, causing the inactivation of the AKT signalling pathway and eventually reducing the expression of PCNA, CyclinD1, MMP9 and Bcl2. Similarly, the silencing of KIAA1456 resulted in the opposite behaviour. Finally, SSX1 overexpression could partially reverse the KIAA1456-induced biological effect.Conclusion: KIAA1456 may serve as a tumour suppressor via the inactivation of SSX1 and the AKT pathway, providing a promising therapeutic target for epithelial ovarian cancers.