Objective:Bone metastasis is a clinically important outcome of prostate carcinoma(PC).We focused on the phenotypic and functional characterization of a particularly aggressive phenotype within the androgen-independent...Objective:Bone metastasis is a clinically important outcome of prostate carcinoma(PC).We focused on the phenotypic and functional characterization of a particularly aggressive phenotype within the androgen-independent bone metastasis-derived PC3 cell line.These cells,originated from the spontaneous conversion of a CD44-negative subpopulation,stably express the CD44 v8-10 isoform(CD44 v8-10 pos)and display stem cell-like features and a marked invasive phenotype in vitro that is lost upon CD44 v8-10 silencing.Methods:Flow cytometry,enzyme-linked immunoassay,immunofluorescence,and Western blot were used for phenotypic and immunologic characterization.Real-time quantitative polymerase chain reaction and functional assays were used to assess osteomimicry.Results:Analysis of epithelial–mesenchymal transition markers showed that CD44 v8-10 pos PC3 cells surprisingly display epithelial phenotype and can undergo osteomimicry,acquiring bone cell phenotypic and behavioral traits.Use of specific si RNA evidenced the ability of CD44 v8-10 variant to confer osteomimetic features,hence the potential to form bone-specific metastasis.Moreover,the ability of tumors to activate immunosuppressive mechanisms which counteract effective immune responses is a sign of the aggressiveness of a tumor.Here we report that CD44 v8-10 pos cells express programmed death ligand 1,a negative regulator of anticancer immunity,and secrete exceptionally high amounts of interleukin-6,favoring osteoclastogenesis and immunosuppression in bone microenvironment.Notably,we identified a novel pathway activated by CD44 v8-10,involving tafazzin(TAZ)and likely the Wnt/TAZ axis,known to play a role in upregulating osteomimetic genes.Conclusions:CD44 v8-10 could represent a marker of a more aggressive bone metastatic PC population exerting a driver role in osteomimicry in bone.A novel link between TAZ and CD44 v8-10 is also shown.展开更多
基金supported by funding by Ateneo Sapienza University(Grant Nos.RP 11816427B97420 and RG11916B7AF0C02D)to A.R.
文摘Objective:Bone metastasis is a clinically important outcome of prostate carcinoma(PC).We focused on the phenotypic and functional characterization of a particularly aggressive phenotype within the androgen-independent bone metastasis-derived PC3 cell line.These cells,originated from the spontaneous conversion of a CD44-negative subpopulation,stably express the CD44 v8-10 isoform(CD44 v8-10 pos)and display stem cell-like features and a marked invasive phenotype in vitro that is lost upon CD44 v8-10 silencing.Methods:Flow cytometry,enzyme-linked immunoassay,immunofluorescence,and Western blot were used for phenotypic and immunologic characterization.Real-time quantitative polymerase chain reaction and functional assays were used to assess osteomimicry.Results:Analysis of epithelial–mesenchymal transition markers showed that CD44 v8-10 pos PC3 cells surprisingly display epithelial phenotype and can undergo osteomimicry,acquiring bone cell phenotypic and behavioral traits.Use of specific si RNA evidenced the ability of CD44 v8-10 variant to confer osteomimetic features,hence the potential to form bone-specific metastasis.Moreover,the ability of tumors to activate immunosuppressive mechanisms which counteract effective immune responses is a sign of the aggressiveness of a tumor.Here we report that CD44 v8-10 pos cells express programmed death ligand 1,a negative regulator of anticancer immunity,and secrete exceptionally high amounts of interleukin-6,favoring osteoclastogenesis and immunosuppression in bone microenvironment.Notably,we identified a novel pathway activated by CD44 v8-10,involving tafazzin(TAZ)and likely the Wnt/TAZ axis,known to play a role in upregulating osteomimetic genes.Conclusions:CD44 v8-10 could represent a marker of a more aggressive bone metastatic PC population exerting a driver role in osteomimicry in bone.A novel link between TAZ and CD44 v8-10 is also shown.
