• Toxicological Research
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• v.17
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• pp.59-69
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• 2001

Arsenic exposure is associated with several human diseases, including cancers, atherosclerosis, hypertension, and cerebrovascular diseases. In cultured cells, arsenite, an inorganic arsenic com-pound, was demonstrated to interfere with many physiological functions, such as enhancement of oxidative stress, delay of cell cycle progression, and induction of structural and numerical changes of chromosomes. The objective of this study is to investigate the effects of arsenic exposure on gene expression profiles by colorimetric cDNA microarray technique. HFW (normal human diploid skin fibroblasts), CL3 (human lung adenocarcinoma cell line), and HaCaT (immortalized human keratinocyte cell line) were treated with 5 $\mu\textrm{M}$ or 10 $\mu\textrm{M}$ sodium arsenite for 6 or 16 h, respectively. By a dual-color detection system, the expression profile of arsenite-treated cultures was compared to that of control cultures. Several genes expressed differentially were identified on the microarray membranes. For example, MDM2, SWI/SNF, ubiquitin specific protease 4, MAP3K11, RecQ protein-like 5, and Ribosomal protein Ll0a were consistently induced in all three cell types by arsenite, whereas prohibitin, cyclin D1, nucleolar protein 1, PCNA, Nm23, and immediate early protein (ETR101) were apparently inhibited. The present results suggest that arsenite insults altered the expression of several genes participating in cellular responses to DNA damage, stress, transcription, and cell cycle arrest.

• Biomolecules & Therapeutics
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• v.26 no.1
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• pp.39-44
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• 2018

In 1923, Dr. Warburg had observed that tumors acidified the Ringer solution when 13 mM glucose was added, which was identified as being due to lactate. When glucose is the only source of nutrient, it can serve for both biosynthesis and energy production. However, a series of studies revealed that the cancer cell consumes glucose for biosynthesis through fermentation, not for energy supply, under physiological conditions. Recently, a new observation was made that there is a metabolic symbiosis in which glycolytic and oxidative tumor cells mutually regulate their energy metabolism. Hypoxic cancer cells use glucose for glycolytic metabolism and release lactate which is used by oxygenated cancer cells. This study challenged the Warburg effect, because Warburg claimed that fermentation by irreversible damaging of mitochondria is a fundamental cause of cancer. However, recent studies revealed that mitochondria in cancer cell show active function of oxidative phosphorylation although TCA cycle is stalled. It was also shown that blocking cytosolic NADH production by aldehyde dehydrogenase inhibition, combined with oxidative phosphorylation inhibition, resulted in up to 80% decrease of ATP production, which resulted in a significant regression of tumor growth in the NSCLC model. This suggests a new theory that NADH production in the cytosol plays a key role of ATP production through the mitochondrial electron transport chain in cancer cells, while NADH production is mostly occupied inside mitochondria in normal cells.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.2
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• pp.293-296
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• 2003

Prunellae Spica is a flower petal of Prunella vulgaris var. lilacina used for treatment of lymphoma, breast cancer, hepatitis and pathological fluid related diseases in oriental medicine. We tried to evaluate the mechanism of Prunellae Spica in the treatment of cancer. The ethyl acetate layer of Prunellae Spica showed a good cytotoxicity on U937 cells with IC50 of 8 ug/ml. It induced apoptosis in U937 dose-dependently by cell cycle analysis following PI staining. We also confirmed it induced DNA fragmentation in U937 cells from the concentration of 10 ug/ml. From western blot assay we observed the ethyl acetate layer of Prunellae Spica downregulated procaspase-3 and cleaved PARP in a dose dependent manner, whereas it didn't affect bax and bcl-2. Taken together, these results indicate the ethyl acetate layer of Prunellae Spica can induce apoptosis in U937 cells suggesting it can be potently applied to cancer.

• Environmental Analysis Health and Toxicology
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• v.13 no.1_2
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• pp.1-9
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• 1998

The ROS-producing potency of chromium compounds of several oxidation states were determined in the H4 cells. $K_2Cr_2O_7$ as Cr (VI), synthetic Cr (V) compounds and Cr (III) as TPP produced high level of ROS. However, ROS values of Cr-picolinate as Cr (III), CrCl$_2$, CrCI$_2$, were almost equal to the control. The effects of physiological antioxidants compounds which react with free radicals were examined for their effects on chromate-induced production of reactive oxygen species (ROS) in A549 cells after the addition of $K_2Cr_2O_7$. The compounds used were vitamin C (ascorbate), vitamin E ($\alpha$-tocopherol), superoxide dismutase (SOD) and catalase. The preincubation of ascorbate (200uM) with A549 cells for 20hr resulted in a significant reduction of hexavalent chromate(100uM) induced ROS. However, there is no effects of preincubation of the cells with vitamin E succinate (10 and 20uM, 20hr) on the ROS production. Also, the effects of Cr (VI) on the cell cycle of A549 cells was measured by adding the DNA intercalating agent, propidium iodide. S phase of the cell cycle was increased by the chromium (VI) compounds up to 20uM indicating toxicity or possible mitogenic action of the cell. The shoulder in Go/G1 phase at 20uM Cr (VI) with 24 hr treatment indicates apoptosis.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.6
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• pp.1423-1430
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• 2009

Rosmarinic acid frequently found as a secondary metabolite in herbs and medicinal plants, has exhibited antimicrobial, antiviral, antioxidative, and anti-inflammatory activities. The proliferation and migration of human aortic smooth muscle cells (HASMC) in response to activation by various stimuli plays a critical role in the initiation and development of atherosclerosis. This study was conducted to examine the effects of Rosmarinic acid on the proliferation and migration of HASMC. Rosmarinic acid suppressed the proliferation of HASMC via induction of the expression of apoptotic proteins including cleaved poly ADP-ribose polymerase (PARP), and caspase-3. Rosmarinic acid decreased anti-apoptotic Bcl-2 and increased pro-apoptotic Bax. Moreover, treatment of rosmarinic acid decreased the G1/S cycle regulation proteins (cyclin D1, cyclin E, CDK2, CDK4 and CDK6) and increased p21, p27 and p53. Rosmarinic acid also blocked HASMC migration via suppression of MMP-9 and MMP-2. Taken together, these results indicate that rosmarinic acid has the potential for use as an anti-atherosclerosis agent.

• Molecules and Cells
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• v.42 no.7
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• pp.546-556
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• 2019

Protein phosphatase 4 (PP4) is a crucial protein complex that plays an important role in DNA damage response (DDR), including DNA repair, cell cycle arrest and apoptosis. Despite the significance of PP4, the mechanism by which PP4 is regulated remains to be elucidated. Here, we identified a novel PP4 inhibitor, protein phosphatase 4 inhibitory protein (PP4IP) and elucidated its cellular functions. PP4IP-knockout cells were generated using the CRISPR/Cas9 system, and the phosphorylation status of PP4 substrates (H2AX, KAP1, and RPA2) was analyzed. Then we investigated that how PP4IP affects the cellular functions of PP4 by immunoprecipitation, immunofluorescence, and DNA double-strand break (DSB) repair assays. PP4IP interacts with PP4 complex, which is affected by DNA damage and cell cycle progression and decreases the dephosphorylational activity of PP4. Both overexpression and depletion of PP4IP impairs DSB repairs and sensitizes cells to genotoxic stress, suggesting timely inhibition of PP4 to be indispensable for cells in responding to DNA damage. Our results identify a novel inhibitor of PP4 that inhibits PP4-mediated cellular functions and establish the physiological importance of this regulation. In addition, PP4IP might be developed as potential therapeutic reagents for targeting tumors particularly with high level of PP4C expression.

• Korean Journal of Microbiology
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• v.7 no.1
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• pp.10-21
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• 1969

The effect of glucose and 2-thiobarbituric acid on the biosynthesis of cell constituents such as protein, carbohydrate, DNA, RNA, phospholipid and PCA-soluble phosphate compounds in Chlorella duing the life cycle was measured, and the changes in the content of these main cellular components of the algal cell were analyzed in connection with the nuclear and cytoplasmic divison. In the normal autotrophic synchronous culture the contents of protein, RNA, and DNA in the cell showed a chracteristic changes according to the progress of cell development, increasing more or less throughout all the life cycle. The synthesis of protein is more prominent in the division period nad that of DNA is more active in the ripening period, while the synthesis of RNA is more rapid in the growing and ripening periods than other developmental stages. The period of division cycle was little affected by glucose in the medium, although the synchrony of the growth and cellular division was disturbed and the n value increased. The cotents of protein, carbohydrate, RNA nad DNA of the cell were increased by the glucose treatment throughout all the life cycle. On the other hand, both of cellular growth and division were retarded severely and the n value was decreased by the 2-thiobarbituric acid treatment throughout all the life cycle. On the other hand, both of cellular growth and division were retarded severely and the n value was decreased by the 2-thiobarbituric acid treatment. The synthesis of protein, carbohydrate, DNA, RNA and phospholipid of the cell was also retarded by 2-thiobarbituric acid. In the autotrophic, mixotrophic and 2-thiobarbituric acid-treated cultures, each having different mode cytoplasmic division, a common general schema occurring in the cell during the life cycle may be drawn as follows. The ratio of RNA to protein attains maximum value in the $L_1$-cell stage prior to the nuclear division and thereafter decreases during the periods of ripening and division. The ratio of PCA-soluble phosphate compounds to protein increased from the begining of the culture to $L_4$-cell stage successively and thereafter decreased gradually during the division period, while the ratio of protein to DNA kept almost constant up to the division period and thereafter increased during the division period. Therefore, it is presumed that the increase in the ratio of RNA to protein is to be an inducer of nuclear division and that the cytoplasmic division is induced by the increase in the ratio of protein to DNA.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.1
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• pp.183-189
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• 2003

Platycodi Radix, the root of Platycodon grandiflorum, commonly known as Doraji, is used as a traditional oriental medicine. Extracts from the roots of P. grandiflorum have been reported to have wide ranging health benefits. We investigated the effects of an aqueous extract from the roots of P. grandiflorum (AEPG) on the cell proliferation of human lung carcinoma A549 cells in order to understand its anti-proliferative mechanism. AEPG treatment resulted in the inhibition of cell proliferation in a concentration-dependent manner. This anti-proliferative effect of A549 cells by AEPG treatment was associated with morphological changes such as membrane shrinking, cell rounding up and inhibition of cell migration. DNA flow cytometric histograms showed that populations of both Sand G2/M phase of the cell cycle were increased by AEPG treatment in a concentration-dependent manner. AEPG treatment induced a marked accumulation of tumor suppressor p53 and a concomitant induction of cyclin-dependent kinase (Cdk) inhibitor p21 and p27. In addition, SSS treatment resulted in down-regulation of Cdk2 and Cdk4 expression. The present results indicated that AEPG-induced inhibition of lung cancer cell proliferation is associated with the blockage of S to G2/M phase progression the induction of apoptosis. Taken together, these findings suggest that P. grandiflorum has strong potential for development as an agent for prevention against human lung cancer.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.3
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• pp.306-312
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• 2013

Costunolide ($C_{15}H_{20}O_2$) is a sesquiterpene lactone that was isolated from many herbal medicines and it has diverse effects (anti-viral, anti-fungal, and anti-inflammatory) according to previous reports. However, the anti-cancer effects of Costunolide and its mechanism of actions are not well known in estrogen receptor positive breast cancer. In this study, we observed that costunolide suppresses cell growth in estrogen receptor positive MCF-7 breast cancer cells as shown by MTT assay and soft agar colony formation assay. To examine the mechanism by which costunolide inhibits MCF-7 cell growth, we performed FACS analysis. We found that costunolide induced G2/M and S cell cycle arrest, and regulated cycle-related protein expression. In addition, costunolide inhibited ERK signaling pathway and induced autophagy. Therefore, costunolide might be a good and useful chemotherapy agent for estrogen receptor positive breast cancer patients.

• Journal of Physiology & Pathology in Korean Medicine
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• v.28 no.3
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• pp.310-316
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• 2014

Oldenlandia diffusa, Cremastra appendiculata and Fritillaria thunbergii are widely distributed in the Korea, China and Japan, and has been used in traditional medicine for various diseases, such as pharyngolaryngitis, tonsillitis, goiter and stomach ulcer. However, the anti-cancer activities in human breast cancer have not been clearly elucidated yet. In this study, it was compared the in vitro cytotoxic effects of single and complex treatment of O. diffusa, C. appendiculata and F. thunbergii. We treat human breast cancer MCF-7 cells with O. diffusa, C. appendiculata and F. thunbergii. And we evaluated viability, growth inhibition, morphological changes, apoptotic bodies formation, measurement of the cell cycle and formation of DNA fragmentation of these cells. It was found that single treatment of O. diffusa could inhibit the cell proliferation in human breast cancer MCF-7 cells. However, complex treatment of O. diffusa, C. appendiculata and F. thunbergii is weakly or not affect the cell proliferation of MCF-7 cells. And anti-proliferative effects of O. diffusa in MCF-7 cells was associated with G1 arrest of cell cycle. These findings suggest that O. diffusa may be a potential chemotherapeutic agent for the control of human breast cancer cells and further studies will be needed to identify the molecular mechanisms.