Project description:The Calcium-Sensing receptor (CaSR) is a G proteins-coupled receptor involved in calcium homeostasis. The CaSR regulates cell proliferation and apoptosis and has been suggested to play an antitumor role in colorectal cancer. However it is down-regulated during carcinogenesis and in more malignant tumors its expression is lost.
Project description:Calcium and 1,25-dihydroxyvitamin D3 (1,25D3), through the actions of their respective receptors, the Ca2+-sensing receptor (CaSR) and the vitamin D receptor (VDR), potentiate keratinocyte differentiation. VDR regulates epidermal keratinocyte proliferation and differentiation by modulating gene transcription, whereas the CaSR, a member of the family C G-protein coupled receptor, calcium mobilizes intracellular calcium and induces the formation of cell-cell junctions. 1,25D3 augments the sensitivity of the prodifferentiating actions of calcium by increasing the expression of CaSR. CaSR- and VDR-deficient keratinocytes share common characteristics such as abnormal intercellular adhesion and sphigolipid metabolism. Both CaSR and VDR are abundantly expressed in epidermal stem cell populations including CD34 expressing bulge keratinocytes in hair follicles and basal cells in interfollicular epidermis. To delineate the role of CaSR- and VDR-dependent pathways in regulating epidermal development and functions in physiological state, we generated conditional CaSR-null and VDR-null mice, where Casr and VDR gene was removed from keratinocytes. Keratinocyte-specific CaSR-null and VDR-null mice manifest distinct phenotypes. CaSR-null mice display defective epidermal permeability barrier function due to aberrant keratinocyte differentiation. VDR-null mice develop alopecia after completing the first hair follicle cycling. Concurrent ablation of CaSR and VDR genes in keratinocytes delays rate of wound repair and increases incidence of skin tumor formation to a greater extent than deletion of the CaSR or VDR alone, indicative of synergistic effects of calcium and 1,25D3 signaling. Gene expression profiles and subsequent pathway analysis on the epidermis derived from 5-day-old neonates revealed that ablation of CaSR or VDR increased expression of genes associated with cancer progression and metastasis. Deletion of VDR markedly inhibited signaling pathways that regulate hair development. Furthermore, concurrent ablation of CaSR and VDR significantly suppressed calcium, VDR, Wnt/b-catenin signaling, as well as epithelial adherence junction signaling to maintain appropriate keratinocyte adhesion. These results indicated the interplay of calcium/CaSR and 1,25D3/VDR signaling in keratinocyte proliferation and differentiation, and their importance in maintaining normal epidermal adhesion and functions. n=3 CON and KO (each sample contain RNA isolated from neonatal epidermis separated from 3 mice)
Project description:Calcium and 1,25-dihydroxyvitamin D3 (1,25D3), through the actions of their respective receptors, the Ca2+-sensing receptor (CaSR) and the vitamin D receptor (VDR), potentiate keratinocyte differentiation. VDR regulates epidermal keratinocyte proliferation and differentiation by modulating gene transcription, whereas the CaSR, a member of the family C G-protein coupled receptor, calcium mobilizes intracellular calcium and induces the formation of cell-cell junctions. 1,25D3 augments the sensitivity of the prodifferentiating actions of calcium by increasing the expression of CaSR. CaSR- and VDR-deficient keratinocytes share common characteristics such as abnormal intercellular adhesion and sphigolipid metabolism. Both CaSR and VDR are abundantly expressed in epidermal stem cell populations including CD34 expressing bulge keratinocytes in hair follicles and basal cells in interfollicular epidermis. To delineate the role of CaSR- and VDR-dependent pathways in regulating epidermal development and functions in physiological state, we generated conditional CaSR-null and VDR-null mice, where Casr and VDR gene was removed from keratinocytes. Keratinocyte-specific CaSR-null and VDR-null mice manifest distinct phenotypes. CaSR-null mice display defective epidermal permeability barrier function due to aberrant keratinocyte differentiation. VDR-null mice develop alopecia after completing the first hair follicle cycling. Concurrent ablation of CaSR and VDR genes in keratinocytes delays rate of wound repair and increases incidence of skin tumor formation to a greater extent than deletion of the CaSR or VDR alone, indicative of synergistic effects of calcium and 1,25D3 signaling. Gene expression profiles and subsequent pathway analysis on the epidermis derived from 5-day-old neonates revealed that ablation of CaSR or VDR increased expression of genes associated with cancer progression and metastasis. Deletion of VDR markedly inhibited signaling pathways that regulate hair development. Furthermore, concurrent ablation of CaSR and VDR significantly suppressed calcium, VDR, Wnt/b-catenin signaling, as well as epithelial adherence junction signaling to maintain appropriate keratinocyte adhesion. These results indicated the interplay of calcium/CaSR and 1,25D3/VDR signaling in keratinocyte proliferation and differentiation, and their importance in maintaining normal epidermal adhesion and functions. n=3 CON and DKO (each sample contain RNA isolated from neonatal epidermis separated from 3 mice)
Project description:Calcium and 1,25-dihydroxyvitamin D3 (1,25D3), through the actions of their respective receptors, the Ca2+-sensing receptor (CaSR) and the vitamin D receptor (VDR), potentiate keratinocyte differentiation. VDR regulates epidermal keratinocyte proliferation and differentiation by modulating gene transcription, whereas the CaSR, a member of the family C G-protein coupled receptor, calcium mobilizes intracellular calcium and induces the formation of cell-cell junctions. 1,25D3 augments the sensitivity of the prodifferentiating actions of calcium by increasing the expression of CaSR. CaSR- and VDR-deficient keratinocytes share common characteristics such as abnormal intercellular adhesion and sphigolipid metabolism. Both CaSR and VDR are abundantly expressed in epidermal stem cell populations including CD34 expressing bulge keratinocytes in hair follicles and basal cells in interfollicular epidermis. To delineate the role of CaSR- and VDR-dependent pathways in regulating epidermal development and functions in physiological state, we generated conditional CaSR-null and VDR-null mice, where Casr and VDR gene was removed from keratinocytes. Keratinocyte-specific CaSR-null and VDR-null mice manifest distinct phenotypes. CaSR-null mice display defective epidermal permeability barrier function due to aberrant keratinocyte differentiation. VDR-null mice develop alopecia after completing the first hair follicle cycling. Concurrent ablation of CaSR and VDR genes in keratinocytes delays rate of wound repair and increases incidence of skin tumor formation to a greater extent than deletion of the CaSR or VDR alone, indicative of synergistic effects of calcium and 1,25D3 signaling. Gene expression profiles and subsequent pathway analysis on the epidermis derived from 5-day-old neonates revealed that ablation of CaSR or VDR increased expression of genes associated with cancer progression and metastasis. Deletion of VDR markedly inhibited signaling pathways that regulate hair development. Furthermore, concurrent ablation of CaSR and VDR significantly suppressed calcium, VDR, Wnt/b-catenin signaling, as well as epithelial adherence junction signaling to maintain appropriate keratinocyte adhesion. These results indicated the interplay of calcium/CaSR and 1,25D3/VDR signaling in keratinocyte proliferation and differentiation, and their importance in maintaining normal epidermal adhesion and functions. n=3 CON and KO (each sample contain RNA isolated from neonatal epidermis separated from 3 mice)
Project description:Calcium and 1,25-dihydroxyvitamin D3 (1,25D3), through the actions of their respective receptors, the Ca2+-sensing receptor (CaSR) and the vitamin D receptor (VDR), potentiate keratinocyte differentiation. VDR regulates epidermal keratinocyte proliferation and differentiation by modulating gene transcription, whereas the CaSR, a member of the family C G-protein coupled receptor, calcium mobilizes intracellular calcium and induces the formation of cell-cell junctions. 1,25D3 augments the sensitivity of the prodifferentiating actions of calcium by increasing the expression of CaSR. CaSR- and VDR-deficient keratinocytes share common characteristics such as abnormal intercellular adhesion and sphigolipid metabolism. Both CaSR and VDR are abundantly expressed in epidermal stem cell populations including CD34 expressing bulge keratinocytes in hair follicles and basal cells in interfollicular epidermis. To delineate the role of CaSR- and VDR-dependent pathways in regulating epidermal development and functions in physiological state, we generated conditional CaSR-null and VDR-null mice, where Casr and VDR gene was removed from keratinocytes. Keratinocyte-specific CaSR-null and VDR-null mice manifest distinct phenotypes. CaSR-null mice display defective epidermal permeability barrier function due to aberrant keratinocyte differentiation. VDR-null mice develop alopecia after completing the first hair follicle cycling. Concurrent ablation of CaSR and VDR genes in keratinocytes delays rate of wound repair and increases incidence of skin tumor formation to a greater extent than deletion of the CaSR or VDR alone, indicative of synergistic effects of calcium and 1,25D3 signaling. Gene expression profiles and subsequent pathway analysis on the epidermis derived from 5-day-old neonates revealed that ablation of CaSR or VDR increased expression of genes associated with cancer progression and metastasis. Deletion of VDR markedly inhibited signaling pathways that regulate hair development. Furthermore, concurrent ablation of CaSR and VDR significantly suppressed calcium, VDR, Wnt/b-catenin signaling, as well as epithelial adherence junction signaling to maintain appropriate keratinocyte adhesion. These results indicated the interplay of calcium/CaSR and 1,25D3/VDR signaling in keratinocyte proliferation and differentiation, and their importance in maintaining normal epidermal adhesion and functions.
Project description:Calcium and 1,25-dihydroxyvitamin D3 (1,25D3), through the actions of their respective receptors, the Ca2+-sensing receptor (CaSR) and the vitamin D receptor (VDR), potentiate keratinocyte differentiation. VDR regulates epidermal keratinocyte proliferation and differentiation by modulating gene transcription, whereas the CaSR, a member of the family C G-protein coupled receptor, calcium mobilizes intracellular calcium and induces the formation of cell-cell junctions. 1,25D3 augments the sensitivity of the prodifferentiating actions of calcium by increasing the expression of CaSR. CaSR- and VDR-deficient keratinocytes share common characteristics such as abnormal intercellular adhesion and sphigolipid metabolism. Both CaSR and VDR are abundantly expressed in epidermal stem cell populations including CD34 expressing bulge keratinocytes in hair follicles and basal cells in interfollicular epidermis. To delineate the role of CaSR- and VDR-dependent pathways in regulating epidermal development and functions in physiological state, we generated conditional CaSR-null and VDR-null mice, where Casr and VDR gene was removed from keratinocytes. Keratinocyte-specific CaSR-null and VDR-null mice manifest distinct phenotypes. CaSR-null mice display defective epidermal permeability barrier function due to aberrant keratinocyte differentiation. VDR-null mice develop alopecia after completing the first hair follicle cycling. Concurrent ablation of CaSR and VDR genes in keratinocytes delays rate of wound repair and increases incidence of skin tumor formation to a greater extent than deletion of the CaSR or VDR alone, indicative of synergistic effects of calcium and 1,25D3 signaling. Gene expression profiles and subsequent pathway analysis on the epidermis derived from 5-day-old neonates revealed that ablation of CaSR or VDR increased expression of genes associated with cancer progression and metastasis. Deletion of VDR markedly inhibited signaling pathways that regulate hair development. Furthermore, concurrent ablation of CaSR and VDR significantly suppressed calcium, VDR, Wnt/b-catenin signaling, as well as epithelial adherence junction signaling to maintain appropriate keratinocyte adhesion. These results indicated the interplay of calcium/CaSR and 1,25D3/VDR signaling in keratinocyte proliferation and differentiation, and their importance in maintaining normal epidermal adhesion and functions.
Project description:Calcium and 1,25-dihydroxyvitamin D3 (1,25D3), through the actions of their respective receptors, the Ca2+-sensing receptor (CaSR) and the vitamin D receptor (VDR), potentiate keratinocyte differentiation. VDR regulates epidermal keratinocyte proliferation and differentiation by modulating gene transcription, whereas the CaSR, a member of the family C G-protein coupled receptor, calcium mobilizes intracellular calcium and induces the formation of cell-cell junctions. 1,25D3 augments the sensitivity of the prodifferentiating actions of calcium by increasing the expression of CaSR. CaSR- and VDR-deficient keratinocytes share common characteristics such as abnormal intercellular adhesion and sphigolipid metabolism. Both CaSR and VDR are abundantly expressed in epidermal stem cell populations including CD34 expressing bulge keratinocytes in hair follicles and basal cells in interfollicular epidermis. To delineate the role of CaSR- and VDR-dependent pathways in regulating epidermal development and functions in physiological state, we generated conditional CaSR-null and VDR-null mice, where Casr and VDR gene was removed from keratinocytes. Keratinocyte-specific CaSR-null and VDR-null mice manifest distinct phenotypes. CaSR-null mice display defective epidermal permeability barrier function due to aberrant keratinocyte differentiation. VDR-null mice develop alopecia after completing the first hair follicle cycling. Concurrent ablation of CaSR and VDR genes in keratinocytes delays rate of wound repair and increases incidence of skin tumor formation to a greater extent than deletion of the CaSR or VDR alone, indicative of synergistic effects of calcium and 1,25D3 signaling. Gene expression profiles and subsequent pathway analysis on the epidermis derived from 5-day-old neonates revealed that ablation of CaSR or VDR increased expression of genes associated with cancer progression and metastasis. Deletion of VDR markedly inhibited signaling pathways that regulate hair development. Furthermore, concurrent ablation of CaSR and VDR significantly suppressed calcium, VDR, Wnt/b-catenin signaling, as well as epithelial adherence junction signaling to maintain appropriate keratinocyte adhesion. These results indicated the interplay of calcium/CaSR and 1,25D3/VDR signaling in keratinocyte proliferation and differentiation, and their importance in maintaining normal epidermal adhesion and functions.
Project description:Calcimimetic agents allosterically increase the calcium (Ca2+) sensitivity of the calcium-sensing receptor (CaSR), which is expressed in the tubular system and to a lesser extent in podocytes. Activation of this receptor can reduce glomerular proteinuria and structural damage in proteinuric animal models. However, the precise role of the podocyte CaSR is still unclear. A CaSR knockdown in cultured murine podocytes and a podocyte-specific CaSR knockout in BALB/c mice were generated to study its role in proteinuria and kidney function. Podocyte CaSR knockdown abolished the calcimimetic R-568 mediated Ca2+-influx, disrupted the actin cytoskeleton, reduced cellular attachment and migration velocity. Adriamycin (ADR)-induced proteinuria enhanced glomerular CaSR expression in wild type mice. Albuminuria, podocyte foot process effacement, podocyte loss and glomerular sclerosis were significantly more pronounced in ADR-treated podocyte-specific CaSR knockout mice compared to wild type littermates. The co-treatment of WT mice with ADR and the calcimimetic cinacalcet reduced the proteinuria in WT, but not in podocyte specific CaSR knockout mice. In addition, four children with nephrotic syndrome, objecting glucocorticoid therapy, were treated with cinacalcet for 1 to 33 days. Proteinuria declined transiently by up to 96% and edema resolved. The activation of podocyte CaSR regulates key podocyte functions in vitro and reduces toxin induced proteinuria and glomerular damage in mice. Our findings suggest a potential novel role of CaSR signaling in control of glomerular disease. Proteomic samples: two backgrounds (CaSR Knockdown vs WT) two conditions (Treatment = 1µM R568 vs untreated control) two timepoints (24h and 48h) five replicates each 2 x 2 x 2 x 5 = 40 samples
Project description:To further elucidate the mechanism of calcium mediated chemoprevention of colorectal cancer,we have employed whole genome microarray expression profiling as a discovery platform to identify genes that differentially expressed in mice from high calcium group compared those from DMH group.The mice of DMH group were received normal diet (calcium concentration,1.24%) and subcutaneous injection of 1,2-Dimethylhydrazine at a dose of 20 mg/kg once weekly for 20 weeks,the mice of high calcium group were received high calcium diet(calcium concentration,3%) and subcutaneous injection of 1,2-Dimethylhydrazine at a dose of 20 mg/kg once weekly for 20 weeks.The mice were sarcrificed at 24 week.Nine normal colonic mucosa (3 from DMH group, 3 from high calcium group mice with tumors, and 3 from high calcium group mice without tumors) were used for the microarray analysis. The differentially expressed genes were indentified between high calcium group and DMH group,as long as differentially expressed pathways and gene ontology terms.