The effects of the an immunosuppressive drug cyclos- porine A (CsA), on the salivary gland are largely unknown, even though clinical trials for the stimulation of salivation using CsA have been attempted. Cyclophilin A (CypA) is known to be a binding protein for CsA. CypA has cell proliferation and tissue matrix change activities. In our present study, the presence of CypA in the gland and effects of CsA on CypA expression were investigated by immu- nohistochemistry, immunoblotting and RT-PCR analyses. CypA was immunohistochemically detected in various kinds of ducts in the submandibular glands of Sprague Dawley rats. The CypA mRNA level was highest at postnatal day 1 and gradually decreased in a time-dependent manner up to adulthood. The expression of CypA increased after a 10 day subcutaneous administration of CsA in postnatal day 1 rats. Surgical sections of the chorda-lingual nerve with impaired salivation showed no changes in CypA expression. A cell proliferation assay using PCNA anti-serum showed inc- reased cell division following CsA treatment. These results suggest that CsA and CypA may act on ductal cells to regulate saliva composition rather than salivation levels.

Plasminogen activators(PA) such as urokinase(uPA) and tissue type plasminogen activators(tPA), physiologically catalyze the conversion of the plasminogen to the wide spectrum proteinase plasmin. Because uPA and tPA are involved in cell growth, differentiation and migration of oral cancer, oral epithelial carcinogenesis including transformation of precancerous lesion into oral squamous cell carcinoma with PA is very interesting. It is important to prevent precancerous condition from transfoming into oral squamous cell carcinoma by the inhibitory effect of various drug. It is well known that cyclosporine A(CsA) as immunosuppressive properties exerts anti-cancer effects. Recently it is widely accepted that cultured immortalized oral keratinocyte (IHOK) is considered as an intermediate stage of oral carcinogenesis and used as precancerous condition in vitro. Thus it was thought that it might be interesting to investigate CsA effect on PA expression of IHOK. IHOK was cultured under KBM bullet kit at 37℃ under 95% CO2 incubator. Subconfluent IHOK cells was treated at different CsA concentration. uPA and tPA protein expression from cultured IHOK cell line has been detected by ELISA analysis in the CsA-treated samples. uPA expression of IHOK was higher than that of NHOK, while tPA was similar to that of NHOK. After CsA treatment, CsA might not effect the expression of uPA of IHOK, while showed a little effect on tPA of IHOK. It suggested that CsA had no effect in uPA expression of IHOK although uPA could be used as a marker for precancerous lesion.

Cyclosporine A (Cs A) which is a highly lipophilic cyclic undecapeptide mainly used for its immunosuppressive properties exert a wide spectrum of biological activities including fungicidal antiproliferactive, anti-inflammatory and chemotherapuetic effects. Human salivary gland adenocarcinoma is very aggressive characteristics, which is need to get the effective chemotherapuetic methods. Subconfluent SGT cell cultures have been treated with CsA at in vivo relevant concentrations for 24h. MTT assay for cellular proliferation of cultured SGT cell line has been performed and TGase 1 activity assay for cellular differentiation has been detected in the CsA-treated samples. It suggested that CsA could have an inhibitory effect in the proliferation of SGT cell line but no in the differentiation.

Gingival overgrowth can cause dental occlusion and seriously interfere with mastication, speech, and dental hygiene. It is observed in 25 to 81% of renal transplant patients treated with cyclosporine A (CsA). CsA-induced gingival overgrowth (CIGO) is caused by quantitative alteration of the extracellular matrix components, particularly collagen. However, the molecular mechanisms involved in the pathogenesis of CIGO remain poorly understood, despite intense clinical and laboratory investigations. The aim of the present work is to identify differentially expressed genes closely associated with CIGO. Human gingival fibroblasts were isolated by primary explant culture of gingival tissues from five healthy subjects (HGFs) and two patients with the CIGO (CIGO-HGFs). The proliferative activity of CsA-treated HGFs and CIGO-HGFs was examined using the MTT assay. The identification of differentially expressed genes in CsA-treated CIGO-HGF was performed by differential display reverse transcriptase-polymerase chain reaction (RT-PCR) followed by DNA sequencing. CsA significantly increased the proliferation of two HGFs and two CIGO-HGFs, whereas three HGFs were not affected. Seven genes, including the beta subunit of prolyl 4-hydroxylase (P4HB) and testican 1, were upregulated by CsA in a highly proliferative CIGO-HGF. The increased P4HB and testican-1 mRNA levels were confirmed in CsA-treated CIGO-HGFs by semiquantitative RT-PCR. Furthermore, CsA increased type I collagen mRNA levels and suppressed MMP-2 mRNA levels, which are regulated by P4HB and testican-1, respectively. These results suggest that CsA may induce gingival overgrowth through the upregulation of P4HB and testican-1, resulting in the accumulation of extracellular matrix components.