Apoptotic Effect of Co-treatment with Curcumin and Cisplatin on SCC25 Human Tongue Squamous Cell Carcinoma Cell Line

Curcumin is a widely used flavoring agent in food, and it has been reported to inhibit cell growth, to induce apoptosis, and to have antitumor activity in many cancers. Cisplatin is one of the most potent known anticancer agents and shows significant clinical activity against a variety of solid tumors. This study was undertaken to investigate the synergistic apoptotic effects of co-treatment with curcumin and cisplatin on human tongue SCC25 cells. To investigate whether the co-treatment efficiently reduced the viability of the SCC25 cells compared with the two treatments separately, an MTT assay was conducted. The induction and the augmentation of apoptosis were confirmed by DNA electrophoresis, Hoechst staining, and an analysis of DNA hypoploidy. Western blot, MMP and immunofluorescence tests were also performed to evaluate the expression levels and the translocation of apoptosis-related proteins following the co-treatment. In this study, following the co-treatment with curcumin and cisplatin, the SCC25 cells showed several forms of apoptotic manifestation, such as nuclear condensation, DNA fragmentation, reduction of MMP, increased levels of Bax, decreased levels of Bcl-2, and decreased DNA content. In addition, they showed a release of cytochrome c into the cytosol, translocation of AIF and DFF40 (CAD) to the nuclei, and activation of caspase-7, caspase-3, PARP, and DFF45 (ICAD). In contrast, separate treatments of 5 microM of curcumin or 4 microg/ml of cisplatin, for 24 hours, did not induce apoptosis. Therefore, our data suggest that combination therapy with curcumin and cisplatin could be considered as a novel therapeutic strategy for human oral squamous cell carcinoma.

A Natural Product, Chios Gum Mastic, Induces the Death of HL-60 Cells via Apoptosis and Cell Cycle Arrest

Chios gum mastic (CGM) is produced from Pistiacia lentiscus L var chia, which grows only on Chios Island in Greece. CGM is a kind of resin extracted from the stem and leaves, has been used for many centuries in many Mediterranean countries as a dietary supplement and folk medicine for stomach and duodenal ulcers. CGM is known to induce cell cycle arrest and apoptosis in some cancer cells. This study was undertaken to investigate the alteration of the cell cycle and induction of apoptosis following CGM treatment of HL-60 cells. The viability of the HL-60 cells was assessed using the MTT assay. Hoechst staining and DNA electrophoresis were employed to detect HL-60 cells undergoing apoptosis. Western blotting, immunocytochemistry, confocal microscopy, FACScan flow cytometry, MMP activity and proteasome activity analyses were also employed. CGM treatment of HL-60 cells was found to result in a dose- and time-dependent decrease in cell viability and apoptotic cell death. Tested HL-60 cells showed a variety of apoptotic manifestations and induced the downregulation of G1 cell cycle-related proteins. Taken collectively, our present findings demonstrate that CGM strongly induces G1 cell cycle arrest via the modulation of cell cycle-related proteins, and also apoptosis via proteasome, mitochondrial and caspase cascades in HL-60 cells. Hence, we provide evidence that a natural product, CGM could be considered as a novel therapeutic for human leukemia.

Chios Gum Mastic Induces Cell Cycle Arrest and Apoptosis in Human Osteosarcoma Cells / 대한해부학회지

Chios gum mastic (CGM) is a resin produced from the stem and leaves of Pistiacia lentiscus L var chia, a plant which grows only on Chios Island in Greece. CGM has been used for many centuries as a dietary supplement and folk medicine for stomach and duodenal ulcers in many Mediterranean countries and is also known to induce cell cycle arrest and apoptosis in some cancer cells. This study was undertaken to investigate the alteration of the cell cycle and induction of apoptosis by CGM treatment on human osteosarcoma (HOS) cells. The viability and the growth inhibition of HOS cells were assessed by the MTT assay and clonogenic assay respectively. The hoechst staining, TUNEL assay and DNA electrophoresis were conducted to observe the HOS cells undergoing apoptosis. HOS cells were treated with CGM, and Western blotting, immunocytochemistry, confocal microscopy, FACScan flow cytometry, mitochondrial membrane potential change and proteasome activity were conducted. CGM treatment of HOS cells was found to result in a dose- and time-dependent decrease in cell viability, a dose-dependent inhibition of cell growth, and apoptotic cell death. Tested HOS cells also showed several lines of apoptotic manifestation and G1 arrest in cell cycle progression. In summary, this study clearly demonstrated that CGM induces G1 cell cycle arrest via the modulation of cell cycle-related proteins, and apoptosis via proteasome, mitochondrial and caspase cascades in HOS cells. Therefore, our data provide the possibility that a natural product, CGM could be considered as a novel therapeutic strategy for human osteosarcoma.

Chios Gum Mastic Induces Cell Cycle Arrest and Apoptosis in YD9 Human Oral Squamous Carcinoma Cells / 체질인류학회지

Chios gum mastic (CGM) is obtained from the stem and leaves of Pistacia lentiscus trees and has been extensively used for centuries in Mediterranean and Middle Eastern countries, both as a dietary supplement and herbal remedy. This study was undertaken to examine in vitro effects of cytotoxicity and growth inhibition, and the molecular mechanism underlying modulation of cell cycle and induction of apoptosis in YD9 human oral squamous carcinoma cell line treated with CGM. The viability of YD9 cells and human normal keratinocyes (HaCaT cells), and the growth inhibition of YD9 cells were assessed by the MTT assay and clonogenic assay respectively. The hoechst staining and DNA electrophoresis were conducted to observe the YD9 cells undergoing apoptosis. YD9 cells were treated with CGM, and Western blotting, immunocytochemistry, confocal microscopy and FACScan flow cytometry were conducted. Mitochondrial membrane potential change and proteasome activity were measured. CGM treatment on YD9 cells resulted in a does-dependent inhibition of cell growth and induced apoptotic cell death. And tested YD9 cells showed several lines of apoptotic manifestation. Flow cytometric analysis revealed that CGM resulted in G1 arrest in cell cycle progression which was associated with decrease in the protein expression of cyclin D1, cyclin D3, Cdk2 and Cdk4, and increase in the protein expression of p21(WAF1/CIP1) and p53. These results demonstrate that CGM induces G1 the cell cycle arrest via the modulation of cell cycle-related proteins, and apoptosis via mitochondria and caspase pathway in YD9 cells, suggesting that CGM can be considered as a novel therapeutic strategy for human oral squamous cell carcinoma from its strong cell cycle arrest and apoptosis-inducing activity.

Effect of calcium and vitamin D supplementation on bone formation around titanium implant in osteoporosis-induced rats

PURPOSE: The purpose of this study was to observe the effect of calcium and vitamin D to the titanium implant osseointegration in the osteoporosis-induced animal model. MATERIAL AND METHOD: Thirty-two rats, 10 weeks of age, were divided into two groups: experimental group was ingested additional calcium and vitamin D, and a control group was not. Titanium screw implant(diameter, 2.0 mm; length, 3.5 mm; pitch-height 0.4 mm) were placed into tibia of 32 rats, 16 in the control group and 16 in the experimental group. The rats were sacrificed at 1, 2, 4 and 8 weeks after implantation for histopathologic examination, histomorphometric analysis and immunohistochemistry with fibronectin and collagen type I antibody. RESULT: In histopathological findings, newly formed bone was seen at 2 weeks and became lamellar bone at 4 weeks, and mature trabecullar bone was seen at 8 weeks in experimental group. In control group, thickness of regenerated bone increased till 4 weeks gradually and trabecullar bone was seen at 8 weeks. In histomorphometric analysis, marrow bone density increased significantly in experimental group compared to control group. Fibronectin immunoreactivity was strong at 2 weeks in experimental group and reduced after 4 weeks gradually. But it was maintained continuously from 2 to 8 weeks in control group. Collagen type I immunoreactivity was very strong from 2 to 4 week in experimental group. And the amount of Collagen type I expression was more abundant in experimental group. CONCLUSION: The results of this study suggest that calcium and vitamin D supplementation promote bone healing around titanium implants in osteoporosis induced animals.

Effect of Calcium and Vitamin D Supplementation on Bone Formation Around Titanium Implant

The purpose of this study was to observe the effect of calcium and vitamin D to the titanium implant osseointegration in animal model. 32 rats, 10 weeks of age, were divided into two group: additional calcium and vitamin D supplementation group and a control group. Titanium screw implant(diameter, 2.0mm; length, 3.5mm; pitch-height 0.4 mm) were placed into tibia of 32 rats, 16 in the control group and 16 in the experimental group. The rats were sacrificed at different time interval(1, 2, 4, and 8 weeks after implantation) for histopathologic observation, histomorphometric analysis and immunohistochemistry with osteocalcin and osteopontin antibody. Histopathologically findings, newly formed bone was seen at 1 weeks and became lamellar bone at 2 weeks, and mature trabecullar bone was seen at 4 weeks experimental group. In control group, thickness of regenerated bone increased till 4 weeks gradually and trabecullar bone was seen at 8 weeks. By histomorphometric analysis, bone marrow density was increased significantly at 1 and 2 weeks in experimental group compared to control group. Osteocalcin immunoreactivity was strong at 1 week experimental group and reduced after 4 weeks gradually. But it was continuously weakly from 1 to 4 weeks in control group. Osteopontin immunoreactivity was very strong in newly formed bone from 2 to 8 weeks experimental group. And the amount of osteopontin expression was more abundant in experimental group. The results of this study suggest that calcium and vitamin D supplementation promotes bone healing around dental implants.