As the most aggressive breast cancer,triple-negative breast cancer(TNBC) is still incurable and very prone to metastasis.The transform growth factor β(TGF-β)-induced epithelial—mesenchymal transition(EMT) is crucia...As the most aggressive breast cancer,triple-negative breast cancer(TNBC) is still incurable and very prone to metastasis.The transform growth factor β(TGF-β)-induced epithelial—mesenchymal transition(EMT) is crucially involved in the growth and metastasis of TNBC.This study reported that a natural compound isotoosendanin(ITSN) reduced TNBC metastasis by inhibiting TGF-β-induced EMT and the formation of invadopodia.ITSN can directly interact with TGF-β receptor type-1(TGFβR1) and abrogated the kinase activity of TGFβR1,thereby blocking the TGF-β-initiated downstream signaling pathway.Moreover,the ITSN-provided inhibition on metastasis obviously disappeared in TGFβR1-overexpressed TNBC cells in vitro as well as in mice bearing TNBC cells overexpressed TGFβR1.Furthermore,Lys232 and Asp351 residues in the kinase domain of TGFβR1 were found to be crucial for the interaction of ITSN with TGFβR1.Additionally,ITSN also improved the inhibitory efficacy of programmed cell death 1 ligand 1(PD-L1) antibody for TNBC in vivo via inhibiting the TGF-β-mediated EMT in the tumor microenvironment.Our findings not only highlight the key role of TGFβR1 in TNBC metastasis,but also provide a leading compound targeting TGFβR1 for the treatment of TNBC metastasis.Moreover,this study also points out a potential strategy for TNBC treatment by using the combined application of anti-PD-L1 with a TGFβR1 inhibitor.展开更多
In this study,we hypothesized that Piezo 1 channels mediate the compression-enhanced invasive phenotype of cancer cells via a caveolae-dependent mechanism.To test this hypothesis,we examined in vitro cultured human br...In this study,we hypothesized that Piezo 1 channels mediate the compression-enhanced invasive phenotype of cancer cells via a caveolae-dependent mechanism.To test this hypothesis,we examined in vitro cultured human breast cancer cells for their ability to invade and degrade extracellular matrix in the presence or absence of compressive stress,together with corresponding changes in Piezo1 as well as cytoskeletal remodeling and calcium signaling.Here we show that compressive stress enhanced invasion,matrix degradation,and invadopodia formation of breast cancer cells.We further identified Piezo1 as the putative mechanosensitive cellular component that transmits compression to induce calcium influx,which in turn triggers several downstream pathways.Interestingly,for the first time we observed inv-adopodia with matrix degradation ability on the apical side of the cells, similar to those commonly observed at the cell s ventral side.Furthermore,we demonstrate that Piezo1 and caveolae were both involved in mediating the compressive stress-induced cancer cell invasive phenotype as Piezo 1 and caveolae were often colocalized,and reduction of Cav-1 expression or disruption of caveolae with methyl-β-cyclodextrin led to not only reduced Piezo1 expression but also attenuation of the invasive phenotypes promoted by compressive stress.Taken together,we first observed that in breast cancer cells,simulating uncontrolled growth-induced compressive stress enhanced cancer cell invasion,matrix degradation,and invadopodia and stress fiber formation.Our study also confirmed that Piezo1 channels are highly expressed in breast cancer cells compared to normal breast cells,and is consistent with the data that compressive stress regulates cell migration of breast cancer cells but not normal breast cells.Additionally,we identified that Piezol mediated these processes and the invasive phenotypes also depended on the integrity of caveolae.These findings provide the first demonstration that compressive stress enhances matrix degradation by brea展开更多
There are many works (i.e. [1]) aiming to find out numerically how positive feedback affects the formation of invadopodia and invasion of cancer cells;however, studies on the cancer cell invasion model with free bound...There are many works (i.e. [1]) aiming to find out numerically how positive feedback affects the formation of invadopodia and invasion of cancer cells;however, studies on the cancer cell invasion model with free boundary are fairly rare. In this paper, we study modified cancer cell invasion model with free boundary, where, free boundary stands for cancer cell membrane, so that we can more precisely describe the positive feedback affects. Firstly, we simplized the model by means of characteristic curve and semi-groups’ property, and obtained the Stefan-like problem by introducing Gaussian Kernel and Green function. Secondly, based on the classical Stefan problem, we derived the integral solution of simplified model, which could lead us a further step to find the solution of modified cancer cell invasion model.展开更多
To screen for additional treatment targets against tongue cancer, we evaluated the contributions of extracellular signal-related kinase(ERK), AKT and ezrin in cancer development. Immunohistochemical staining showed th...To screen for additional treatment targets against tongue cancer, we evaluated the contributions of extracellular signal-related kinase(ERK), AKT and ezrin in cancer development. Immunohistochemical staining showed that ERK and ezrin expressions were significantly higher in invasive squamous cell carcinoma than in carcinoma in situ. To investigate the roles of ERK and ezrin in cancer development, we used the non-woven silica fibre sheet Cellbedwith a structure resembling the loose connective tissue morphology in a novel 3 D culture system. We confirmed that the 3 D system using CellbedTMaccurately mimicked cancer cell morphology in vivo. Furthermore, cell projections were much more apparent in 3 D-cultured tongue cancer cell lines than in 2 D cultures. Typically, under conventional 2 D culture conditions, F-actin and cortactin are colocalized in the form of puncta within cells.However, in the 3 D-cultured cells, colocalization was mainly observed at the cell margins, including the projections. Projections containing F-actin and cortactin colocalization were predicted to be invadopodia. Although suppressing ezrin expression with small interfering RNA transfection caused no marked changes in morphology, cell projection formation was decreased, and the tumour thickness in vertical sections after 3 D culture was markedly decreased after suppressing ERK activity because both the invasion ability and proliferation were inhibited. An association between cortactin activation as well as ERK activity and invadopodia formation was detected. Our novel 3 D culture systems using Cellbed? are simple and useful for in vitro studies before conducting animal experiments. ERK contributes to tongue cancer development by increasing both cancer cell proliferation and migration via cortactin activation.展开更多
Objective:The BRAF inhibitor,vemurafenib,has been widely used in the treatment of patients with melanoma-bearing BRAFV600E mutations.While the initial response to vemurafenib is usually excellent,the majority of patie...Objective:The BRAF inhibitor,vemurafenib,has been widely used in the treatment of patients with melanoma-bearing BRAFV600E mutations.While the initial response to vemurafenib is usually excellent,the majority of patients eventually develop resistance and metastatic disease.However,the underlying molecular mechanism remains elusive.The objective of this study was therefore to identify additional molecular targets responsible for vemurafenib resistance.Methods:Western blots and immunohistochemistry analyses were used to evaluate expressions of PYK2 and p-PYK2 in cultured cells and melanoma tissue microarrays.The relationships of p-PYK2 with clinicopathological parameters were statistically analyzed.Invadopodia cell invasion,and a Ca2+assay were used to determine the effect of vemurafenib resistance-induced p-PYK2 on melanoma progression.A mouse model was used to assess the effects of PYK2 on melanoma metastasis.Results:Elevated p-PYK2 levels were detected in vemurafenib-resistant melanoma cells,and PYK2 was shown to regulate invadopodia formation in melanoma cells.Vemurafenib triggered invadopodia formation by activation of PYK2.Inhibition of PYK2 with either shRNA or the small molecule inhibitor,PF562711,dramatically reduced vemurafenib-induced invadopodia formation.Furthermore,knockdown of PYK2 significantly reduced melanoma lung metastasis in vivo.Increased expressions of p-PYK2 in melanoma patients were positively correlated with advanced stage(P=0.002),metastasis(P<0.001),and Clark grade(P<0.001),and were also associated with short overall survival[hazard ratio(HR)=3.304,P=0.007]and progression-free survival(HR=2.930,P=0.001).Conclusions:PYK2 mediated vemurafenib-induced melanoma cell migration and invasion.Inhibition of PYK2 resensitized melanoma cells to vemurafenib.Phospho-PYK2 was a prognostic biomarker in melanoma patients.展开更多
基金financially supported by the National Natural Science Foundation of China(82273994)the leadership in the Science and National Key Research and Development Program of China(2018YFC1707302)。
文摘As the most aggressive breast cancer,triple-negative breast cancer(TNBC) is still incurable and very prone to metastasis.The transform growth factor β(TGF-β)-induced epithelial—mesenchymal transition(EMT) is crucially involved in the growth and metastasis of TNBC.This study reported that a natural compound isotoosendanin(ITSN) reduced TNBC metastasis by inhibiting TGF-β-induced EMT and the formation of invadopodia.ITSN can directly interact with TGF-β receptor type-1(TGFβR1) and abrogated the kinase activity of TGFβR1,thereby blocking the TGF-β-initiated downstream signaling pathway.Moreover,the ITSN-provided inhibition on metastasis obviously disappeared in TGFβR1-overexpressed TNBC cells in vitro as well as in mice bearing TNBC cells overexpressed TGFβR1.Furthermore,Lys232 and Asp351 residues in the kinase domain of TGFβR1 were found to be crucial for the interaction of ITSN with TGFβR1.Additionally,ITSN also improved the inhibitory efficacy of programmed cell death 1 ligand 1(PD-L1) antibody for TNBC in vivo via inhibiting the TGF-β-mediated EMT in the tumor microenvironment.Our findings not only highlight the key role of TGFβR1 in TNBC metastasis,but also provide a leading compound targeting TGFβR1 for the treatment of TNBC metastasis.Moreover,this study also points out a potential strategy for TNBC treatment by using the combined application of anti-PD-L1 with a TGFβR1 inhibitor.
基金supported by Key Program of NSF of China ( 11532003) to L.D.NSF-MCB 1561794 to A.P.L.
文摘In this study,we hypothesized that Piezo 1 channels mediate the compression-enhanced invasive phenotype of cancer cells via a caveolae-dependent mechanism.To test this hypothesis,we examined in vitro cultured human breast cancer cells for their ability to invade and degrade extracellular matrix in the presence or absence of compressive stress,together with corresponding changes in Piezo1 as well as cytoskeletal remodeling and calcium signaling.Here we show that compressive stress enhanced invasion,matrix degradation,and invadopodia formation of breast cancer cells.We further identified Piezo1 as the putative mechanosensitive cellular component that transmits compression to induce calcium influx,which in turn triggers several downstream pathways.Interestingly,for the first time we observed inv-adopodia with matrix degradation ability on the apical side of the cells, similar to those commonly observed at the cell s ventral side.Furthermore,we demonstrate that Piezo1 and caveolae were both involved in mediating the compressive stress-induced cancer cell invasive phenotype as Piezo 1 and caveolae were often colocalized,and reduction of Cav-1 expression or disruption of caveolae with methyl-β-cyclodextrin led to not only reduced Piezo1 expression but also attenuation of the invasive phenotypes promoted by compressive stress.Taken together,we first observed that in breast cancer cells,simulating uncontrolled growth-induced compressive stress enhanced cancer cell invasion,matrix degradation,and invadopodia and stress fiber formation.Our study also confirmed that Piezo1 channels are highly expressed in breast cancer cells compared to normal breast cells,and is consistent with the data that compressive stress regulates cell migration of breast cancer cells but not normal breast cells.Additionally,we identified that Piezol mediated these processes and the invasive phenotypes also depended on the integrity of caveolae.These findings provide the first demonstration that compressive stress enhances matrix degradation by brea
文摘There are many works (i.e. [1]) aiming to find out numerically how positive feedback affects the formation of invadopodia and invasion of cancer cells;however, studies on the cancer cell invasion model with free boundary are fairly rare. In this paper, we study modified cancer cell invasion model with free boundary, where, free boundary stands for cancer cell membrane, so that we can more precisely describe the positive feedback affects. Firstly, we simplized the model by means of characteristic curve and semi-groups’ property, and obtained the Stefan-like problem by introducing Gaussian Kernel and Green function. Secondly, based on the classical Stefan problem, we derived the integral solution of simplified model, which could lead us a further step to find the solution of modified cancer cell invasion model.
文摘To screen for additional treatment targets against tongue cancer, we evaluated the contributions of extracellular signal-related kinase(ERK), AKT and ezrin in cancer development. Immunohistochemical staining showed that ERK and ezrin expressions were significantly higher in invasive squamous cell carcinoma than in carcinoma in situ. To investigate the roles of ERK and ezrin in cancer development, we used the non-woven silica fibre sheet Cellbedwith a structure resembling the loose connective tissue morphology in a novel 3 D culture system. We confirmed that the 3 D system using CellbedTMaccurately mimicked cancer cell morphology in vivo. Furthermore, cell projections were much more apparent in 3 D-cultured tongue cancer cell lines than in 2 D cultures. Typically, under conventional 2 D culture conditions, F-actin and cortactin are colocalized in the form of puncta within cells.However, in the 3 D-cultured cells, colocalization was mainly observed at the cell margins, including the projections. Projections containing F-actin and cortactin colocalization were predicted to be invadopodia. Although suppressing ezrin expression with small interfering RNA transfection caused no marked changes in morphology, cell projection formation was decreased, and the tumour thickness in vertical sections after 3 D culture was markedly decreased after suppressing ERK activity because both the invasion ability and proliferation were inhibited. An association between cortactin activation as well as ERK activity and invadopodia formation was detected. Our novel 3 D culture systems using Cellbed? are simple and useful for in vitro studies before conducting animal experiments. ERK contributes to tongue cancer development by increasing both cancer cell proliferation and migration via cortactin activation.
基金supported by National Natural Science Foundation of China(Grant Nos.81871990 and 31671448)Yunnan Applicative and Basic Research Program(Grant Nos.2019FY003030 and 202101AV070002)a grant(2019KF006)from Conservation and Utilization of Bio-Resources in Yunnan(YNCUB).
文摘Objective:The BRAF inhibitor,vemurafenib,has been widely used in the treatment of patients with melanoma-bearing BRAFV600E mutations.While the initial response to vemurafenib is usually excellent,the majority of patients eventually develop resistance and metastatic disease.However,the underlying molecular mechanism remains elusive.The objective of this study was therefore to identify additional molecular targets responsible for vemurafenib resistance.Methods:Western blots and immunohistochemistry analyses were used to evaluate expressions of PYK2 and p-PYK2 in cultured cells and melanoma tissue microarrays.The relationships of p-PYK2 with clinicopathological parameters were statistically analyzed.Invadopodia cell invasion,and a Ca2+assay were used to determine the effect of vemurafenib resistance-induced p-PYK2 on melanoma progression.A mouse model was used to assess the effects of PYK2 on melanoma metastasis.Results:Elevated p-PYK2 levels were detected in vemurafenib-resistant melanoma cells,and PYK2 was shown to regulate invadopodia formation in melanoma cells.Vemurafenib triggered invadopodia formation by activation of PYK2.Inhibition of PYK2 with either shRNA or the small molecule inhibitor,PF562711,dramatically reduced vemurafenib-induced invadopodia formation.Furthermore,knockdown of PYK2 significantly reduced melanoma lung metastasis in vivo.Increased expressions of p-PYK2 in melanoma patients were positively correlated with advanced stage(P=0.002),metastasis(P<0.001),and Clark grade(P<0.001),and were also associated with short overall survival[hazard ratio(HR)=3.304,P=0.007]and progression-free survival(HR=2.930,P=0.001).Conclusions:PYK2 mediated vemurafenib-induced melanoma cell migration and invasion.Inhibition of PYK2 resensitized melanoma cells to vemurafenib.Phospho-PYK2 was a prognostic biomarker in melanoma patients.
