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In the present study, we identified a missense mutation (G199V) in KAT-18 cell line established from primary cultures of anaplastic thyroid cancer (ATC). Notably, knockdown of this mutant (mt) p53 reduced cell viability and exerted antitumor activity equivalent to high doses of several chemotherapeutic agents. We showed that p53 knockdown had an antitumor effect via the induction of apoptosis. We further examined the underlying mechanism by which mt p53 (G199V) gains antiapoptotic function in KAT-18 cells. Microarray analysis revealed that p53 knockdown modified the expression of numerous apoptosis-related genes. Importantly, p53 knockdown led to downregulation of signal transducer and activator of transcription-3 (STAT3) gene expression. We further observed that p53 knockdown induced the downregulation of STAT3 protein. We also observed that a STAT3 inhibitor augmented the reduction of cell viability induced by p53 knockdown, whereas interleukin-6 treatment alleviated this effect. In addition, overexpression of STAT3 protected ATC cells against cell death induced by p53 knockdown. Taken together, these data show that mt p53 (G199V) gains antiapoptotic function mediated by STAT3 in ATC cells. Inhibition of the function of mt p53 (G199V) could be a novel and useful therapeutic strategy for decreasing the extent and severity of toxicity due to chemotherapeutic agents. (Mol Cancer Res 2009;7(10):1645–54)

Supplementary Data from Mutant p53 (G199V) Gains Antiapoptotic Function through Signal Transducer and Activator of Transcription 3 in Anaplastic Thyroid Cancer Cells

Free fatty acids (FFAs), which are elevated with metabolic syndrome, are considered the principal offender exerting lipotoxicity. Few previous studies have reported a causal relationship between FFAs and osteoarthritis pathogenesis. However, the molecular mechanism by which FFAs exert lipotoxicity and induce osteoarthritis remains largely unknown. We here observed that oleate at the usual clinical range does not exert lipotoxicity while oleate at high pathological ranges exerted lipotoxicity through apoptosis in articular chondrocytes. By investigating the differential effect of oleate at toxic and nontoxic concentrations, we revealed that lipid droplet (LD) accumulation confers articular chondrocytes, the resistance to lipotoxicity. Using high fat diet-induced osteoarthritis models and articular chondrocytes treated with oleate alone or oleate plus palmitate, we demonstrated that articular chondrocytes gain resistance to lipotoxicity through protein kinase casein kinase 2 (PKCK2)—six-transmembrane protein of prostate 2 (STAMP2)—and fat-specific protein 27 (FSP27)-mediated LD accumulation. We further observed that the exertion of FFAs-induced lipotoxicity was correlated with the increased concentration of cellular FFAs freed from LDs, whether FFAs are saturated or not. In conclusion, PKCK2/STAMP2/FSP27-mediated sequestration of FFAs in LD rescues osteoarthritic chondrocytes. PKCK2/STAMP2/FSP27 should be considered for interventions against metabolic OA., Oil droplets protect cartilage from toxic fatty acids Cartilage tissue deals with the stress of exposure to free fatty acids by sequestering the toxic molecules into sub-cellular oil droplets. Young Hyun Yoo from Dong-A University College of Medicine in Busan, South Korea, and coworkers exposed rat cartilage cells to increasing levels of a fatty acid called oleate, a by-product of fat metabolism, and observed that the accumulation of oil droplets conferred resistance to oleate-induced toxicity. In these rat cells and in experiments involving mouse models of osteoarthritis fed a high-fat diet, the researchers then identified three of the protective proteins needed for cartilage tissue to properly quarantine fatty acids into oil droplets. Those proteins — and their connected regulatory networks — could now serve as drug targets for treating metabolic syndrome-associated osteoarthritis.

Free fatty acids (FFAs) are considered the principal inducers of lipotoxicity, leading to cell dysfunction and/or cell death. Lipotoxicity in Schwann cells (SCs) damages neurons, which may be associated with peripheral neuropathies and axon degeneration. However, the molecular mechanism by which FFAs exert lipotoxicity in SCs remains to be established. In the present study, we demonstrate that palmitate exerts lipotoxicity in SCs through apoptosis and that palmitate-induced lipotoxicity in SCs is mediated through reactive oxygen species (ROS) generation. We observed that the six-transmembrane protein of prostate 2 (STAMP2), which plays a pivotal role in lipid homeostasis, is expressed in SCs. We further demonstrate that palmitate induces lipoapoptosis in SCs through ROS generation-mediated STAMP2 downregulation and that STAMP2 depletion accelerates the palmitate-exerted lipoapoptosis in SCs, indicating that STAMP2 confers on SCs the ability to resist palmitate-induced lipotoxicity. In conclusion, palmitate induces lipoapoptosis in SCs through ROS generation-mediated STAMP2 downregulation. Our findings indicate that ROS and STAMP2 may represent suitable targets for pharmacological interventions targeting lipotoxicity-associated peripheral neuropathies and axon degeneration.

Summary Objective Although leptin appears to be an important local and systemic factor influencing cartilage homeostasis, the role of leptin in chondrocyte death is largely unknown. Tumor necrosis factor α (TNF-α) is a pro-inflammatory cytokine that plays a central role in the pathogenesis of articular diseases. This study examines whether leptin modulates TNF-α-induced articular chondrocyte death. Methods Primary rat articular chondrocytes were isolated from knee joint cartilage slices. To induce cell death, the chondrocytes were treated with TNF-α. To examine whether leptin modulates the extent of TNF-α-mediated chondrocyte death, the cells were pretreated with leptin for 3 h before TNF-α treatment followed by viability analysis. To examine the mechanism by which leptin modulates the extent of TNF-α-mediated chondrocyte death, we utilized mitochondrial membrane potential (MMP) measurements, flow cytometry, nuclear morphology observation, co-immunoprecipitation, western blot analysis and confocal microscopy. Results We demonstrated that leptin suppresses TNF-α induced chondrocyte death. We further found that apoptosis partially contributes to TNF-α induced chondrocyte death while necroptosis primarily contributes to TNF-α induced chondrocyte death. In addition, we observed that leptin exerts anti-TNF-α toxicity via c-jun N-terminal kinase (JNK) in rat articular chondrocytes. Conclusion Based on our findings, we suggest that the leptin present in the articular joint fluid protects articular chondrocytes against cumulative mechanical load and detrimental stresses throughout a lifetime, delaying the onset of degenerative changes in chondrocytes. We can further hypothesize that leptin protects articular chondrocytes against destructive stimuli even in the joints of osteoarthritis (OA) patients.

Background & Aims Most studies on the role of STAMP2 in metabolism have used adipose tissue. Little knowledge exists concerning the role of STAMP2 in the liver, which is a metabolically central target. We hypothesized that STAMP2 is involved in non-alcoholic fatty liver disease (NAFLD) pathogenesis. Methods We examined our hypothesis using human NAFLD patient pathology samples and a high-fat diet (HFD)-induced NAFLD mouse model. The molecular mechanism underlying hepatic STAMP2-mediated lipid imbalance was explored using an oleic acid (OA)-induced NAFLD in vitro model. Results Noticeably, the expression level of STAMP2 protein was reduced in the livers obtained from NAFLD patients and HFD-induced NAFLD mice. In vivo knockdown of hepatic STAMP2 by siRNA accelerated hepatic steatosis and insulin resistance in mice fed a HFD. Conversely, the delivery of adenoviral STAMP2 (Ad-STAMP2) improved hepatic steatosis in HFD-induced NAFLD mice. The expression of lipogenic or adipogenic factors was increased in both in vitro and in vivo NAFLD models but was reversed by Ad-STAMP2. Adenoviral overexpression of STAMP2 improved insulin resistance in the HFD-induced NAFLD mice. In vivo and in vitro assays demonstrated that STAMP2 modulates insulin sensitivity and glucose metabolism and that STAMP2 counteracts OA-induced insulin resistance by modulating insulin receptor substrate-1 stability. Conclusions The present study revealed that hepatic STAMP2 plays a pivotal role in preventing HFD-induced NAFLD and that STAMP2 overexpression improves hepatic steatosis and insulin resistance in NAFLD. Our findings indicate that STAMP2 may represent a suitable target for interventions targeting NAFLD.

This study intends to develop R&D policy agendas that are required to prepare a smart library/smart society in Korea libraries. To the end, methodology was established to explore policy issues and agenda for library R&D, and the preliminary agendas were drawn from informetrics, subject analysis, and brainstorming techniques. Then, the preliminary agendas were revised through supplementary works, such as the comprehensive investigation into research papers and the recent research projects. Based on the results, evaluation for the R&D agendas was performed. The Analytic Hierarchy Process (AHP) method was used as a structured technique for analyzing the importance and the priority of the agendas. This study can be used for improving and/or expanding quality of information services in Korean libraries and for exploring the requirements to play a crucial role in the future society.

Background/Aim: Cyclosporine (CsA)-induced kidney injury is characterized by renal dysfunction with inflammatory cell infiltrations, apoptosis and fibrosis. Pleiotropic effects of statins may exert anti-inflammatory, antiapoptotic and antifibrotic actions beyond lipid control. The aim of this study is to investigate whether rosuvastatin (RUS) has anti-inflammatory, antiapoptotic and antifibrotic effects on chronic CsA-induced nephropathy in a rat model. Methods: Male Sprague-Dawley rats fed a low-sodium diet were divided into three treatment groups: control (0.9% saline injection), CsA (15 mg/kg/day by subcutaneous injection), CsA + RUS (10 mg/kg/day by gastric gavage). Renal function, CsA level and lipid levels were measured at the end of 4 weeks. The expression of ED-1, transforming growth factor-β1 (TGF-β1) and α-smooth muscle actin (α-SMA) for inflammation and fibrosis were examined by Western blot analysis. The expression levels of apoptosis-associated factors were examined by Western blot analysis. Apoptosis was evaluated using the terminal deoxynucleotidyl transferase-mediated biotin nick end-labeling (TUNEL) method. Results: Kidney function was decreased in CsA-treated rats compared with controls, which was attenuated by RUS. RUS did not affect the lipid level or the blood CsA level. TUNEL staining showed that RUS inhibited CsA-induced tubular apoptosis. RUS decreased CsA-induced increased expression of Bax/Bcl-2 ratio. The expressions of ED-1, α-SMA, TGF-β1, Smad2/3, Smad4 and p-JNK were increased in CsA-treated rats, which were attenuated by RUS. Tubular atrophy and interstitial fibrosis in CsA-treated rats were attenuated by RUS supplementation. Conclusion: RUS supplementation attenuates proinflammatory and apoptosis-related factors and inhibits the fibrotic pathways including the smad-dependent and smad-independent pathways in a rat model of CsA-induced nephropathy.

This study was conducted to evaluate cytotoxicity due to co-treatment with low-dose Mitomycin-C (MMC) and the histone deacetylase inhibitor, suberoylanilide hydroxamic acid (SAHA) for glaucoma filtration surgery. In this study, the effect of co-treatment with MMC and SAHA to induce apoptosis in cultured conjunctival epithelial cells (CEs) in rabbit was investigated. The cytotoxic potential following co-treatment with MMC and SAHA in CEs via assay for reactive oxygen species (ROS) and lactate dehydrogenase (LDH) was also examined. Co-treatment with MMC and SAHA did not induce apoptosis in CEs. In addition, co-treatment with MMC and SAHA caused no significant alteration of ROS and LDH levels in CEs. This study therefore shows that low-dose MMC could still be used as an antimetabolite in co-treatment with SAHA to effectively inhibit fibrosis of Tenon's capsule fibroblasts (TCFs) following glaucoma filtration surgery, while minimizing cytotoxicity in CEs.

In the present study, we identified a missense mutation (G199V) in KAT-18 cell line established from primary cultures of anaplastic thyroid cancer (ATC). Notably, knockdown of this mutant (mt) p53 reduced cell viability and exerted antitumor activity equivalent to high doses of several chemotherapeutic agents. We showed that p53 knockdown had an antitumor effect via the induction of apoptosis. We further examined the underlying mechanism by which mt p53 (G199V) gains antiapoptotic function in KAT-18 cells. Microarray analysis revealed that p53 knockdown modified the expression of numerous apoptosis-related genes. Importantly, p53 knockdown led to downregulation of signal transducer and activator of transcription-3 (STAT3) gene expression. We further observed that p53 knockdown induced the downregulation of STAT3 protein. We also observed that a STAT3 inhibitor augmented the reduction of cell viability induced by p53 knockdown, whereas interleukin-6 treatment alleviated this effect. In addition, overexpression of STAT3 protected ATC cells against cell death induced by p53 knockdown. Taken together, these data show that mt p53 (G199V) gains antiapoptotic function mediated by STAT3 in ATC cells. Inhibition of the function of mt p53 (G199V) could be a novel and useful therapeutic strategy for decreasing the extent and severity of toxicity due to chemotherapeutic agents. (Mol Cancer Res 2009;7(10):1645–54)

Although alpha alpha B-crystallin is expressed in articular chondrocytes, little is known about its role in these cells. Protein kinase casein kinase 2 (CK2) inhibition induces articular chondrocyte death. The present study examines whether alpha B-crystallin exerts anti-apoptotic activity in articular chondrocytes. Primary rat articular chondrocytes were isolated from knee joint slices. Cells were treated with CK2 inhibitors with or without alpha B-crystallin si RNA. To examine whether the silencing of aB-crystallin sensitizes rat articular chondrocytes to CK2 inhibition induced apoptosis, we assessed apoptosis by performing viability assays, mitochondrial membrane potential measurements, flow cytometry, nuclear morphology observations, and western blot analysis. To investigate the mechanism by which aB-crystallin modulates the extent of CK2 inhibition-mediated chondrocyte death, we utilized confocal microscopy to observe the subcellular location of aB-crystallin and its phosphorylated forms and performed a co-immunoprecipitation assay to observe the interaction between aB-crystallin and CK2. Immunochemistry was employed to examine aB-crystallin expression in cartilage obtained from rats with experimentally induced osteoarthritis (OA). Our results demonstrated that silencing of aB-crystallin sensitized rat articular chondrocytes to CK2 inhibitor -induced apoptosis. Furthermore, CK2 inhibition modulated the expression and subcellular localization of aB-crystallin and its phosphorylated forms and dissociated aB-crystallin from CK2. The population of rat articular chondrocytes expressing aB-crystallin and its phosphorylated forms was reduced in an experimentally induced rat model of OA. In summary, aB-crystallin protects rat articular chondrocytes against CK2 inhibition -induced apoptosis. aB-crystallin may represent a suitable target for pharmacological interventions to prevent OA.

Previous studies reported that a Gamitrinib variant containing triphenylphosphonium (G-TPP) binds to mitochondrial Hsp90 and rapidly inhibits its activity to induce apoptosis. We investigated the mechanisms underlying the antitumor activity of G-TPP in Hep3B hepatocellular carcinoma cells. Contrary to our predictions, we observed mitochondrial elongation in the G-TPP-treated Hep3B cells undergoing apoptosis. We found that the G-TPP-induced mitochondrial elongation in Hep3B cells was caused by a decrease in the mitochondrial fission-regulating protein Drp1 rather than by changes in the mitochondrial fusion machinery proteins Mfn1 and Opa1. Furthermore, G-TPP induced G2-M phase cell cycle arrest by reducing the interaction between CDK1 and cyclin B1. Additionally, reactive oxygen species (ROS) played a pivotal role in G-TPP-induced cell death and mitochondrial elongation in Hep3B cells, and these processes are mediated by the reduced association of CDK1 with cyclin B1 and the suppressed phosphorylation of Drp1 (Ser616). Thus, G-TPP induces cell death and causes Drp1-mediated mitochondrial elongation in Hep3B cells by increasing the ROS level.

We developed amniotic membrane ointment (AMO), and the effect of instilling the AMO after photorefractive keratectomy (PRK) was investigated with respect to inflammatory cell infiltration into the corneal stroma, apoptosis of keratocytes, and suppression of lipid peroxidation of cellular walls. The PRK procedure was performed on both eyes of 10 white rabbits. One eye of each rabbit (the experimental eye) was instilled with the AMO and the other eye of the rabbit (the control eye) with a base ointment 0, 8 and 16 h after the PRK procedure. Corneal specimens were collected 24 h after the PRK procedure. Hematoxylin-eosin stain and TUNEL assay were conducted to demonstrate polymorphonuclear and apoptotic cells, respectively. To assess lipid peroxidation, immunohistochemical staining with an antibody to malondialdehyde was undertaken. Compared to the control, the cornea instilled with the AMO had significantly less polymorphonuclear cells infiltrating into the corneal stroma as well as keratocytes subjected to apoptosis. These corneas also showed a significantly less extent of lipid peroxidation than the control. These data support that instillation of the AMO effectively reduced the recruitment of polymorphonuclear cells, the induction of apoptosis in keratocytes, and lipid peroxidation induced by PRK. Thus, this study could provide basic data on the clinical application of the AMO in the days ahead.

This study intends to analyze the utility of library catalogs from library users `point of view. Emphasis was on verifying how useful library catalogs are as a tool in order to satisfy the information need of library users. To the end, this study developed the criteria and indicators that can be used to measure the utility of library catalogs from users` viewpoint. On the basis of it, the utility of library catalogs was measured systematically. Sample catalog records for the utility verification were selected from 6 most representative university libraries in Korea. The result of verification was presented and described with the typical examples, and the key factors that caused the low utility of library catalogs were a]so identified and discussed.

This study intends to discuss the knowledge and information resources which Korea and Japan has produced about each other for the period of 101~2000. To this end, we collected comprehensively the monographs produced by each country, and built a database named as "Korea-Japan Knowledge Information System." Using this database, we analyzed the present state and characteristics of the monographs with a special emphasis on the publication period and subject. Also identified was the relationship between the production of monographs and the Korea-Japan relations from a historical perspective. Finally suggested was the establishment of a national information system for the effective management of the produced monographs.onographs.

Since resveratrol is not a potent cytotoxic compound when compared with other chemotherapeutic agents, several previous studies have been performed to obtain synthetic analogs of resveratrol with potent activity. Our previous study demonstrated that the resveratrol analog HS-1793 showed stronger antitumor activity than resveratrol in various cancer cells. We examined the antitumor activity exerted by HS-1793 in prostate cancer cells, and we observed that HS-1793 acts as a polyploidy inducer. Noticeably, multinucleation and polyploidization were induced in most LNCaP cells treated with HS-1793 at the dose causing a slight decline in cell viability. However, the induction of multinucleation and polyploidization was much lower in PC-3 prostate cancer cells treated with the same dose of HS-1793. Western blot and RT-PCR analyses showed that the expression of Aurora B was almost undetectable in LNCaP cells, but it was highly expressed in PC-3 cells. Further, silencing of Aurora B sensitized PC-3 cells to HS-1793-induced multi-nucleation. These results indicate that expression of Aurora B determines multinucleation in prostate cancer cells treated with HS-1793. Additional assays using multiple cancer cell lines show that the population of multinucleated cells induced by HS-1793 treatment is inversely proportional to Aurora B expression. We further elicited that the HS-1793-induced polyploid LNCaP cells are vulnerable to downregulation of Bcl-xL. Since the polyploidization in LNCaP induced by HS-1793 does not appear to cause definite commitment to apoptosis, the termination of polyploid cells by inhibition of Bcl-xL could provide an advantageous means to improve chemotherapeutic efficacy of HS-1793.

Purpose To better understand the mechanism underlying the anti-apoptotic activity of alphaB-crystallin in RPE cells. Methods Cells of the human retinal pigment epithelial line ARPE-19 were treated with a histone deacetylase inhibitor (HDACI), suberoylanilide hydroxamic acid (SAHA), with or without alphaB-crystallin siRNA. To examine the mechanism underlying the cell death induced in ARPE-19 cells, nuclear staining, flow cytometry, DNA electrophoresis, pulse field gel electrophoresis, Western blot analysis, confocal microscopy, and coimmunoprecipitation assay were undertaken. Results The present study demonstrated that an HDACI, SAHA, at the usual doses or the silencing of alphaB-crystallin by siRNA alone did not effectively induce apoptosis in ARPE-19 cells. Silencing of alphaB-crystallin likely abolishes the anti-apoptotic activity of alphaB-crystallin. The data indicated that silencing of alphaB-crystallin sensitizes ARPE19 cells to SAHA-induced apoptosis and leads them to stage 1 apoptosis. alphaB-Crystallin associates with HDAC1 on SC35 speckles, and silencing of alphaB-crystallin abolishes this association, resulting in the induction of apoptosis. The data indicated that the association between alphaB-crystallin and HDAC1 on SC35 speckles plays a pivotal role in anti-apoptotic activity. Conclusions Knockout of alphaB-crystallin may be a promising new approach to enhance therapeutic potency for proliferative vitreoretinopathy without compromising efficacy.

Purpose: This study was undertaken to develop a new treatment modality that would be able to minimize fibrosis and provide better outcome with glaucoma filtration surgery (GFS). Methods: We examined whether co-treatment with mitomycin-C (MMC) and histone deacetylase inhibitor (HDACi) suberoylanilide hydroxamic acid (SAHA) efficiently induces apoptosis on rabbit Tenon's capsule fibroblasts (TCF) in vitro. We further examined the effect of co-treatment with SAHA and MMC on the alteration of IOP and the bleb survival in rabbits following GFS. Results: Co-treatment of MMC and SAHA efficiently induces apoptosis in TCFs via the up-regulation of p53 and increased phosphorylation of p53 on serine 15 and 392. Also, co-treatment of SAHA and low-dose MMC decreases IOP, prolongs bleb survival, and induces apoptosis of cells under the bleb area following GFS. Conclusion: This study shows that a co-treatment of SAHA and MMC could improve the outcome of GFS.

Doxorubicin is known to be the most effective single cytotoxic drug against anaplastic thyroid carcinoma (ATC). Although doxorubicin has been shown to cause cell death, at least partly, by inducing apoptosis in ATC cells, the mechanism underlying its pharmacological efficacy has not been fully delineated. We, in this study, revealed that doxorubicin induced apoptosis in ATC cells by altering the acetylation state of histone. Doxorubicin reduced histone deacetylase activity and induced hyperacetylation of histone 3. Noticeably, ladder-like DNA fragments from their genomic DNA on agarose gel were not detected irrespective of several lines of evidence supporting the induction of apoptosis. Pulse field electrophoresis showed disintegration of nuclear DNA into giant fragments of 1-2 Mbp and high molecular-weight fragments of 100-1000 kbp. We next examined whether a histone deacetylase inhibitor trichostatin A (TsA) augmented doxorubicin-induced apoptosis in ATC cells. TSA potentiated doxorubicin-induced stage I apoptosis in ATC cells. Our study sheds light on the development of a new combination therapy strategy for more effective responses for ATC treatment.

We investigated the induction and underlying mechanism of apoptosis in retinal pigment epithelial cells by the inhibition of proteasome activity using lactacystin. Rat retinal pigment epithelial cell line retinal pigment epithelial (RPE)-J was used in this study. Apoptosis was evaluated by light and electron microscopies, DNA electrophoresis, and terminal deoxynucleotidyl transferase dUTP nick-end labeling assay. The apoptosis-related proteins were localized in the cells by immunofluorescent microscopy, and the changes of their protein contents and the enzyme activation were monitored by Western blot. Mitochondrial membrane potential was quantified by measuring J aggregate (5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazol carbocyanine iodide) fluorescence. To measure changes in intracellular pH, cells were loaded with 2',7'-bis(carboxyethyl)-5(6')-carboxyfluorescein and assayed by flow cytometry. To elucidate the type of transport system involving intracellular pH regulation, several transporter inhibitors were used, and their effect on pH and membrane potential was assayed as described above. Lactacystin treatment significantly induced apoptosis in RPE-J cells. During the RPE cell apoptosis, 1) cytochrome c and Smac/DIABLO were released into cytosol from mitochondria, 2) translocation of apoptosis-inducing factor to the nucleus was evident, 3) Bax protein seemed to translocate to mitochondria, 4) procaspase-3 and poly(ADP-ribose) polymerase were cleaved, and 5) nuclear condensation and DNA fragmentation were clearly observed. Noticeably, a transient increase of mitochondrial membrane potential was coincidentally detected with the intracellular alkalinization after lactacystin administration. Furthermore, the lactacystin-induced early alkalinization was inhibited by 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonate, an inhibitor of Cl(-)/HCO(3)(-) anion exchanger, which also prevented early mitochondrial hyperpolarization and apoptosis. Lactacystin-induced apoptosis in RPE-J cells is closely associated with an early mitochondrial hyperpolarization induced by intracellular alkalinization.

To study whether the synthetic ursodeoxycholic acid (UDCA) and chenodeoxycholic acid (CDCA) derivatives, which we have synthesized and have reported their apoptosis-inducing effect, have the effect on the proliferation of retinal pigment epithelial cells.UDCA, CDCA, and their synthetic derivatives were administered in culture to the human retinal pigment cell line, ARPE-19. The effect on cell viability and growth was assessed by trypan blue dye exclusion. In order to evaluate the type of cell death, mitochondrial membrane potential assay, DNA electrophoresis, TUNEL assay, nuclear staining and Western blotting for caspase-3 and poly(ADP-ribose) polymerase (PARP) activities were conducted.Unlike UDCA and CDCA, which did not exhibit a significant effect on viability, their synthetic derivatives decreased the viability of ARPE-19 cells in a concentration-dependent manner. The cells treated with the synthetic derivatives did not demonstrate the characteristic findings of apoptosis, such as DNA ladder, DNA fragmentation, nuclear condensation or fragmentation, and caspase-3 and PARP activation. The reduction of mitochondrial membrane potential was shown. In electron microscopical study nuclear condensation was not shown.The synthetic UDCA and CDCA derivatives induced nonapoptotic death of ARPE-19 cells.