Limits...
Trail resistance induces epithelial-mesenchymal transition and enhances invasiveness by suppressing PTEN via miR-221 in breast cancer.

Wang H, Xu C, Kong X, Li X, Kong X, Wang Y, Ding X, Yang Q - PLoS ONE (2014)

Bottom Line: In our present experiment, we successfully utilized breast cancer cell line MDA-MB-231 to establish TRAIL-resistant cell line.We found resistance to TRAIL could induce epithelial-mesenchymal transition (EMT) and enhance invasiveness.Re-expression of miR-221 or targeting PTEN might serve as potential therapeutic approaches for the treatment of Trail-resistant breast cancer.

View Article: PubMed Central - PubMed

Affiliation: Department of Oncology, Qilu Hospital, Shandong University, Jinan, Shandong Province, China; Department of Oncology, Affiliated Hospital of Qingdao University Medical College, Qingdao, Shandong Province, China; Department of Breast Surgery, Qilu Hospital, Shandong University, Jinan, Shandong Province, China.

ABSTRACT
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can selectively induce apoptosis of cancer cells and is verified effective to various cancers. However, a variety of breast cancer cell lines are resistant to TRAIL and the mechanisms of resistance are largely unknown. In our present experiment, we successfully utilized breast cancer cell line MDA-MB-231 to establish TRAIL-resistant cell line. We found resistance to TRAIL could induce epithelial-mesenchymal transition (EMT) and enhance invasiveness. We further demonstrated PTEN was down-regulated in TRAIL-resistant cells. Silencing miR-221, PTEN expression was up-regulated, the process of EMT could be reversed, and the ability of migration and invasion were correspondingly weakened. We also demonstrated knockdown of miR-221 could reverse resistance to TRAIL partially by targeting PTEN. Our findings suggest that resistance to TRAIL could induce EMT and enhance invasiveness by suppressing PTEN via miR-221. Re-expression of miR-221 or targeting PTEN might serve as potential therapeutic approaches for the treatment of Trail-resistant breast cancer.

Show MeSH

Related in: MedlinePlus

MiR-221 knockdown could sensitize 231T cells to TRAIL, reverse EMT and reduce cell mobility.A. Cultured 231T-n and 231T-si221 cells with different concentrations of TRAIL in 96-well plates. 48 hours later examined their sensitivity to TRAIL by MTT assay. Points represented the average of three independent experiments. Bars stood for SD; B. The mesenchymal markers, N-cadherin, fibronectin, vimentin and Snail expressed in 231T-n and 231T-si221 cells were detected by western blot assay. β-actin was used as control; C. Migration and invasion assay of 231T-n cells and 231T-si221 cells. Staining the migrated cells with hematoxylin–eosin and count them in 10 representative fields under a light microscope. D. Summary graphs for migration and invasion were also shown, respectively. Data was presented as mean ± SD. *P<0.05; **P<0.01.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4048247&req=5

pone-0099067-g007: MiR-221 knockdown could sensitize 231T cells to TRAIL, reverse EMT and reduce cell mobility.A. Cultured 231T-n and 231T-si221 cells with different concentrations of TRAIL in 96-well plates. 48 hours later examined their sensitivity to TRAIL by MTT assay. Points represented the average of three independent experiments. Bars stood for SD; B. The mesenchymal markers, N-cadherin, fibronectin, vimentin and Snail expressed in 231T-n and 231T-si221 cells were detected by western blot assay. β-actin was used as control; C. Migration and invasion assay of 231T-n cells and 231T-si221 cells. Staining the migrated cells with hematoxylin–eosin and count them in 10 representative fields under a light microscope. D. Summary graphs for migration and invasion were also shown, respectively. Data was presented as mean ± SD. *P<0.05; **P<0.01.

Mentions: To clarify the role of miR-221 in resistance to TRAIL, we performed drug sensitivity test of 231T-si221 cells and 231T-n cells using MTT assay. Data showed that knockdown of miR-221 could recover sectional sensitivity to TRAIL (Figure 7A). Then we detected those EMT markers (including N-cadherin, fibronectin, vimentin) again (Figure 7B). And found that those mesenchymal markers and transcriptional marker Snail were down-regulated, showing that EMT was reversed. Moreover, we performed Transwell test of 231T-n and 231T-si221 cells, and discovered that after inhibition of miR-221, the abilities of migration and invasion were both weakened (Figure 7C and D). All of these results accounted for that miR-221 participated in the resistance to TRAIL, EMT, migration and invasion of MDA-MB-231 cells.


Trail resistance induces epithelial-mesenchymal transition and enhances invasiveness by suppressing PTEN via miR-221 in breast cancer.

Wang H, Xu C, Kong X, Li X, Kong X, Wang Y, Ding X, Yang Q - PLoS ONE (2014)

MiR-221 knockdown could sensitize 231T cells to TRAIL, reverse EMT and reduce cell mobility.A. Cultured 231T-n and 231T-si221 cells with different concentrations of TRAIL in 96-well plates. 48 hours later examined their sensitivity to TRAIL by MTT assay. Points represented the average of three independent experiments. Bars stood for SD; B. The mesenchymal markers, N-cadherin, fibronectin, vimentin and Snail expressed in 231T-n and 231T-si221 cells were detected by western blot assay. β-actin was used as control; C. Migration and invasion assay of 231T-n cells and 231T-si221 cells. Staining the migrated cells with hematoxylin–eosin and count them in 10 representative fields under a light microscope. D. Summary graphs for migration and invasion were also shown, respectively. Data was presented as mean ± SD. *P<0.05; **P<0.01.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4048247&req=5

pone-0099067-g007: MiR-221 knockdown could sensitize 231T cells to TRAIL, reverse EMT and reduce cell mobility.A. Cultured 231T-n and 231T-si221 cells with different concentrations of TRAIL in 96-well plates. 48 hours later examined their sensitivity to TRAIL by MTT assay. Points represented the average of three independent experiments. Bars stood for SD; B. The mesenchymal markers, N-cadherin, fibronectin, vimentin and Snail expressed in 231T-n and 231T-si221 cells were detected by western blot assay. β-actin was used as control; C. Migration and invasion assay of 231T-n cells and 231T-si221 cells. Staining the migrated cells with hematoxylin–eosin and count them in 10 representative fields under a light microscope. D. Summary graphs for migration and invasion were also shown, respectively. Data was presented as mean ± SD. *P<0.05; **P<0.01.
Mentions: To clarify the role of miR-221 in resistance to TRAIL, we performed drug sensitivity test of 231T-si221 cells and 231T-n cells using MTT assay. Data showed that knockdown of miR-221 could recover sectional sensitivity to TRAIL (Figure 7A). Then we detected those EMT markers (including N-cadherin, fibronectin, vimentin) again (Figure 7B). And found that those mesenchymal markers and transcriptional marker Snail were down-regulated, showing that EMT was reversed. Moreover, we performed Transwell test of 231T-n and 231T-si221 cells, and discovered that after inhibition of miR-221, the abilities of migration and invasion were both weakened (Figure 7C and D). All of these results accounted for that miR-221 participated in the resistance to TRAIL, EMT, migration and invasion of MDA-MB-231 cells.

Bottom Line: In our present experiment, we successfully utilized breast cancer cell line MDA-MB-231 to establish TRAIL-resistant cell line.We found resistance to TRAIL could induce epithelial-mesenchymal transition (EMT) and enhance invasiveness.Re-expression of miR-221 or targeting PTEN might serve as potential therapeutic approaches for the treatment of Trail-resistant breast cancer.

View Article: PubMed Central - PubMed

Affiliation: Department of Oncology, Qilu Hospital, Shandong University, Jinan, Shandong Province, China; Department of Oncology, Affiliated Hospital of Qingdao University Medical College, Qingdao, Shandong Province, China; Department of Breast Surgery, Qilu Hospital, Shandong University, Jinan, Shandong Province, China.

ABSTRACT
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can selectively induce apoptosis of cancer cells and is verified effective to various cancers. However, a variety of breast cancer cell lines are resistant to TRAIL and the mechanisms of resistance are largely unknown. In our present experiment, we successfully utilized breast cancer cell line MDA-MB-231 to establish TRAIL-resistant cell line. We found resistance to TRAIL could induce epithelial-mesenchymal transition (EMT) and enhance invasiveness. We further demonstrated PTEN was down-regulated in TRAIL-resistant cells. Silencing miR-221, PTEN expression was up-regulated, the process of EMT could be reversed, and the ability of migration and invasion were correspondingly weakened. We also demonstrated knockdown of miR-221 could reverse resistance to TRAIL partially by targeting PTEN. Our findings suggest that resistance to TRAIL could induce EMT and enhance invasiveness by suppressing PTEN via miR-221. Re-expression of miR-221 or targeting PTEN might serve as potential therapeutic approaches for the treatment of Trail-resistant breast cancer.

Show MeSH
Related in: MedlinePlus