Correction to: Platelets promote breast cancer cell MCF-7 metastasis by direct interaction: surface integrin α2ß1-contacting-mediated activation of Wnt-ß-catenin pathway.

An amendment to this paper has been published and can be accessed via the original article.

Platelets promote breast cancer cell MCF-7 metastasis by direct interaction: surface integrin α2ß1-contacting-mediated activation of Wnt-ß-catenin pathway.

BACKGROUND: Integrin-mediated platelet-tumor cell contacting plays an important role in promoting epithelial-mesenchymal transition (EMT) transformation of tumor cells and cancer metastasis, but whether it occurs in breast cancer cells is not completely clear. OBJECTIVE: The purpose of this study was to investigate the role of integrin α2ß1 in platelet contacting to human breast cancer cell line MCF-7 and its effect on the EMT and the invasion of MCF-7 cells. METHODS: Human platelets were activated by thrombin, and separated into pellets and releasates before the co-incubation with MCF-7 cells. Cell invasion was evaluated by transwell assay. The surface integrins on pellets and MCF-7 cells were inhibited by antibodies. The effect of integrin α2ß1 on Wnt-ß-catenin pathway was assessed by integrin α2ß1-silencing and Wnt-ß-catenin inhibitor XAV. The therapeutic effect of integrin α2ß1-silencing was confirmed in the xenograft mouse model. RESULTS: Pellets promote the invasion and EMT of MCF-7 cells via direct contacting of surface integrin α2ß1. The integrin α2ß1 contacting activates Wnt-ß-catenin pathway and promotes the expression of EMT proteins in MCF-7 cells. The activated Wnt-ß-catenin pathway also promotes the autocrine of TGF-ß1 in MCF-7 cells. Both Wnt-ß-catenin and TGF-ß1/pSmad3 pathways promote the expression of EMT proteins. Integrin α2ß1-silencing inhibits breast cancer metastasis in vivo. CONCLUSIONS: The direct interaction between platelets and tumor cells exerts its pro-metastatic function via surface integrin α2ß1 contacting and Wnt-ß-catenin activation. Integrin α2ß1-silencing has the potential effect of inhibiting breast cancer metastasis.

Microwave hyperthermia enhances the sensitivity of lung cancer cells to gemcitabine through reactive oxygen species­induced autophagic death.

The pleiotropic effects of hyperthermia on cancer cells have been well documented, and microwave hyperthermia (MWHT) has been widely applied for multifarious cancer treatment. However, the mechanisms underlying the anticancer effect of MWHT combined with gemcitabine (GEM) remain poorly understood. The aim of the present study was to investigate the role of autophagy in the thermo­chemotherapy of human squamous cell lung carcinoma cells. It was observed that MWHT combined with GEM potently suppressed the viability of NCI­H2170 and NCI­H1703 cells, and induced G0/G1 cell cycle arrest. Notably, MWHT with GEM induced autophagy, as indicated by the formation of autophagic vacuoles, downregulation of p62 and upregulation of light chain 3­II. It was further demonstrated that the autophagy was due to the production of reactive oxygen species (ROS), whereas N­acetyl cysteine, an ROS scavenger, attenuated the level of autophagy. However, when the autophagy inhibitor 3­methyladenine was used, there was no significant change in the production of ROS. Furthermore, it was observed that MWHT combined with GEM downregulated the protein expression levels of phosphoinositide 3­kinase (PI3K), phosphorylated (p)­PI3K, protein kinase B (AKT), p­AKT, mammalian target of rapamycin (mTOR), p­mTOR, phosphorylated S6 (pS6) and p70 S6 kinase, which are associated with autophagy. In addition, the results demonstrated that ROS served as an upstream mediator of PI3K/AKT/mTOR signaling. In light of these findings, the present study provides original insights into the molecular mechanisms underlying the cell death induced by MWHT combined with GEM, and this may be a promising approach for the treatment of human squamous cell lung carcinoma.

[Combination of phage display and SEREX for screening early lung cancer associated antigens].

OBJECTIVE: To screen out effective lung cancer associated antigens for early diagnosis in order to improve the level of early diagnosis. METHODS: A T7 phage display cDNA library of human early lung cancer was developed. And then differential phage clones were picked out to be sequenced and bioinformatically analyzed. With the 8 screened differential phage clones a lung cancer associated antigen microarray was established to evaluate the single or combined roles of all the selected antigens in the diagnosis of lung cancer by the reaction of the antigens plus serum from normal subjects and patients with lung cancer, respectively. RESULTS: The titer of the constructed cDNA library was 3.71×10 (6); pfu/ml and the number of phage was 1.11×10 (6); pfu, with a recombination rate of cDNA library over 90%. Nine differential phage clones were initially screened out, but the genes of two antigens (A42 and A83) were found the same. Bioinformatics analyses showed that the genes of the 8 antigens were known before and they were all proven to be related with tumor except A64. The positive reaction rates of the 8 antigens with serum from lung cancer patients were significantly higher than that with serum from normal subjects (Ps<0.05). When keeping specificity no less than 60%, the sensitivity of each antigen in predicting lung cancer alone was under 70% and the areas under curve (AUC) of the antigens were all under 0.8. However, when all the antigens were combined to detect lung cancer, the sensitivity and specificity was 90.8% and 94.1%, respectively, and AUC reached up to 0.969. CONCLUSION: A T7 phage display cDNA library with a good quality of capacity, recombination rate and representativeness of human early lung cancer was successfully developed, and 8 lung cancer associated antigens were screened out. A combination of the 8 antigens can greatly improve their value to diagnose lung cancer with a higher sensitivity and specificity (both above 90%)．