• Journal of Photoscience
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• v.9 no.2
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• pp.454-456
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• 2002

It is important to determine the action spectrum of UV-B radiation contained in the sunlight to estimate the risk of skin cancer. We have investigated action spectra for induction of apoptosis and reproductive cell death in L5178Y cells using the Okazaki Large Spectrograph at NIBB. L5178Y cells were exposed to light at different wavelengths in UV-B or UV-A region. Frequencies of apoptosis induction and reproductive cell death were determined by counting cells with chromatin condensation, and by the colony formation assay, respectively. The measured sensitivity spectra for the two end-points were in very good agreement. Sensitivity decreased steeply with increase of wavelength in UV-B region and remains nearly constant in UV-A region. The action spectra were also slightly steeper than that for the minimum erythematic dose (MED), but very similar to the light absorption spectrum of DNA in UV-B region. On the other hand, the spectra for both endpoints were similar to MED spectrum but not DNA spectrum in the UV-A region. Also different time-course and morphological difference of apoptosis were found between UV-B (long time, fragmentation) and UV-A (short time, shrinkage) region. These results suggest that DNA damage induced by UV-B light triggers apoptosis and reproductive cell death, but other damaged targets (membrane, protein and so on) trigger these effects in UV-A region.

• Proceedings of the Ginseng society Conference
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• 1978.09a
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• pp.43-49
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• 1978

This study was devised to observe the cytotoxic activity of extracts of Panax ginseng root against some cancer cells and to purify the crude extract. Three kinds of cancer cells(leukemic cells L5178Y, HeLa cells and Sarcoma 180 cells) and mouse embryo cells (as normal cells) were used for this study. The ginseng roots were extracted with petroleum ether in soxhlet apparatus, and the crude extracts were purified by the silicic acid column chromatography and thin-layer chromatography methods. The results obtained are summarized as follows; 1. Eight to ten mg of the petroleum ether extract (crude extract) were obtained from 1 g of Panax ginseng root, and its activities per mg were about 1,000 units. 2. Doubling time of the L5178Y cells was increased to two fold by 24 hours incubation in culture medium containing about one ${\mu}g$ of extract per ml, and eight and ten folds higher concentration of ginseng extract were required for the Sarcoma 180 cells and HeLa cells, respectively, than for the leukemic cells(L5178Y) to inhibit the cellular growth to the same degree. 3. When the L5178Y cells were exposed to medium containing various concentration of the extract for 24 hours before initiation of the soft agar cloning procedure, about $99\%$ of the L5178Y cells were killed at concentration of 8 units per ml. 4. The growth rate of mouse embryo cell (as normal cell) was not affected by the culture with media containing various amounts (1.45 to 30.0 ${\mu}g/ml$) of the extract. 5. The crude extract could be purified about four times by silicic acid column chromatography using several solvent systems, and one spot of active compound could be obtained on the thin-layer chromatogram. 6. In the Swiss mice inoculated with Sarcoma 180 cells, a survival time of the experimental group (injection group of active compound) was extended more. 1.5 to 2.0 times than the control group's(no injection group).

• Environmental Mutagens and Carcinogens
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• v.19 no.1
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• pp.7-13
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• 1999

The mouse lymphoma thymidine kinase (tk+/-) gene assay (MOLY) using L5178Y tk+/- mouse lymphoma cell line is one of the mammalian forward mutation assays. It is well known that MOLY has many advantages and more sensitive than the other mammalian forward mutation assays such as x-linked hyposanthine phosphoribosyltransferase (hprt) gene assay. The target gene of MOLY is a heterozygous tk+/- gene located in 11 chromosome of L5178Y tk+/- cell, so it is able to detect the wide range of genetic changes like point mutation, deletion, rearrangement, and mitotic recombination within tk gene or deletion of entire chromosome 11. MOLY has relatively short expression time (2-3 days) compared to 1 week of hprt gene assay. MOLY can also induce relatively high mutant frequency so a large number of events can be recorded. The bimodal distribution of colony size which may indicate gene mutation and chromosome breakage potential of chemicals according to mutation scale such as large normal-growing mutants and small slow-growing mutants can be observed in this assay. The statistical analysis of data can be performed using the MUTANT program developed by York Electronic Research in association with Hazelton as recommended by the UKEMS (United Kingdom Environmental Mutagen Society) guidelines. This report reviewed MOLY using the microtiter cloning technique (microwell assay).

• Environmental Mutagens and Carcinogens
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• v.22 no.3
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• pp.164-168
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• 2002

Phthalate analogues are a plasticizer and solvent used in industry and were reported to be a potential carcinogen classified in the category of suspected endocrine disruptors. Most common human exposure to these compounds may occur with contaminated food. They may migrate into food from plastic wrap or may enter food from general environmental contamination. Since these substances are not limited to the original products, and enter the environment, they have become widespread environmental pollutants, thus leading to a variety of phthalates that possibly threaten the public health. To determine whether seven phthalate analogues i.e. diallyl phthalate, diisodecyl phthalate, di-n-nonyl phthalate, butyl benzyl phthalate, di-n-octyl phthalate, di-tridecyl phthalate, and dibutyl phthalate, can induce DNA strand breakage that is one of the various factors related to the mechanism of carcinogenicity, the comet assay which has been widely used for the detection and measurement of DNA strand breaks, was conducted in L5178Y mouse lymphoma cells. From these results, seven phthalates revealed dose-dependent decrease of cell viability, however, no remarkable cytotoxicity was observed even at high concentration of 100 $\mu\textrm{g}$/$m\ell$ phthalates. And also, the results showed that the induction of DNA strand breaks by seven phthalates was not significantly different from the control in this study.

• Archives of Pharmacal Research
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• v.8 no.4
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• pp.283-284
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• 1985

It was previously reported that the petroleum ether fraction of the Korean ginseng root shows cytotoxic activities against L1210, L5178Y, Hela cell and Sarcoma 180 cell (1). In this study the cytotoxic substance against L1210 cell was isolated over a silica gel column and a preparative HPLC, followed by the cytotoxic assay (2).

• YAKHAK HOEJI
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• v.42 no.4
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• pp.345-352
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• 1998

Praecoxin A, an ellagitannin, purified from Alnus hirsuta var.microphlla was evaluated on the antitumor activity. Praecoxin A had the significant cytotoxicity to s ix tumor cell lines: human chronic myelogenous leukemia K-562, human promyelocytic leukemia HL-60, mouse leukemia P388, mouse lymphocytic leukemia L-1210, sarcoma-l8O, mouse lymphoma L5178Y except L-1210. And the most sensitive cell line was K-562 ($ED_{50}=2.43{\mu}g/ml$). The $ED_{50} of praecoxin A against HL-60, P388, L-1210, sarcoma7l8O and L5178Y were 6.28, 8.66, 10.00, 7.01, $9.32{\mu}g/ml$, respectively. Praecoxin A showed the increasing effect in life span by 36.8% on the 1st day after treatment of 10mg/kg in mice bearing sarcoma-180 tumor cells (ascitic form) via NCI (National Cancer Institute, U.S.A.) protocol in vivo assay. As a result, praecoxin A is considered to show the antitumor activity.

• Biomolecules & Therapeutics
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• v.17 no.1
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• pp.92-97
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• 2009

As nanomaterials might enter into cells and have high reactivity with intracellular structures, it is necessary to assay possible genotoxic risk of them. One of these approaches, we investigated possible genotoxic potential of gold nanoparticle (AuNP) using L5178Y cells. Four different sizes of AuNP (4, 15, 100 or 200 nm) were synthesized and the sizes and structures of AuNP were analyzed using transmission electron microscopy (TEM), scanning electron microscopy (SEM) and stability was analyzed by a UV/Vis. Spectrophotometer. Cytotoxicity was assessed by direct cell counting, and cellular location was detected by dark field microscope at 6, 24 and 48 h after treatment of AuNP. Comet assay was conducted to examine DNA damage and tumor necrosis factor (TNF)-${\alpha}$ mRNA level was assay by real-time reverse transcription polymerase chain reaction. Synthetic AuNP (4, 50, 100 and 200 nm size) had constant characteristics and stability confirmed by TEM, SEM and spectrophotometer for 10 days, respectively. Dark field microscope revealed the location of AuNP in the cytoplasm at 6, 24 and 48 h. Treatment of 4 nm AuNP induced dose and time dependent cytotoxicity, while other sizes of AuNP did not. However, Comet assay represented that treatment of 100 nm and 200 nm AuNP significantly increased DNA damage compared to vehicle control (p <0.01). Treatment of 100 nm and 200 nm AuNP significantly increased TNF-${\alpha}$ mRNA expression compared to vehicle control (p<0.05, p<0.01, respectively). Taken together, AuNP induced DNA damage in L5178Y cell, associated with induction of oxidative stress.

• Molecular & Cellular Toxicology
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• v.3 no.1
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• pp.23-30
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• 2007

The effects of high energy short wave solar radiation on human skin have received much publicity as the major cause of accelerated skin ageing and of skin cancers. To meet public demand, the cosmetic industry has developed sun protection factor products, which contain a variety of so-called "UV filters", among others benzophenone (BP) and its metabolites are the widely used UV filters. UV filters are also used to prevent UV light from damaging scents and colors in a variety of cosmetics products and to protect of plastic products against light-induced degradation. There are many variants of BP in use. In this respect, to regulate and to evaluate the hazardous effect of BP-type UV filters will be important to environment and human health. The genotoxicity of 7 BP-type UV filters was evaluated in L5178Y $(tk^{+/-})$ mouse lymphoma cells in vitro. BP, benzhydrol, 4-hydroxybenzophenone 2-hydroxy-4-methoxybenzophenone and 2, 4-dihydroxybenzophenone did not induce significant mutation frequencies both in the presence and absence of metabolic activation system. 2, 2'-Dihydroxy-4-methoxybenzophenone appeared the positive results at the highest dose, i.e. 120.4 ${\mu}g/mL$ only in the absence of metabolic activation system. And also, 2, 3, 4-trihydroxybenzophenone revealed a significant increase of mutation frequencies in the range of 138.1-207.2 ${\mu}g/mL$ in the absence of metabolic activation system and 118.3-354.8 ${\mu}g/mL$ in the presence of metabolic activation system. Through the results of MLA with 7 BP-type UV filters in L5178Y cells in vitro, we may provide the important clues on the genotoxic potentials of these BP-type UV filters.

• Biomolecules & Therapeutics
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• v.19 no.2
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• pp.261-266
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• 2011

As recent reports suggest that nanoparticles may penetrate into cell membrane and effect DNA condition, it is necessary to assay possible cytotoxic and genotoxic risk. Three different sizes of magnetic nanoparticle silica (MNP@$SiO_2$) (50, 100 and 200 nm diameter) were tested for cytotoxicity and DNA damage using L5178Y cell. MNP@$SiO_2$ had constant physicochemical characteristics confirmed by transmission electron microscope, electron spin resonance spectrometer and inductively coupled plasma-atomic emission spectrometer for 48 h. Treatment of MNP@$SiO_2$ induced dose and time dependent cytotoxicity. At 6 h, 50, 100 or 200 nm MNP@$SiO_2$ decreased significantly cell viability over the concentration of 125 ${\mu}g/ml$ compared to vehicle control (p<0.05 or p<0.01). Moreover, at 24 h, 50 or 100 nm MNP@$SiO_2$ decreased significantly cell viability over the concentration of 125 ${\mu}g/ml$(p<0.01). And treatment of 200 nm MNP@$SiO_2$ decreased significantly cell viability at the concentration of 62.5 ${\mu}g/ml$ (p<0.05) and of 125, 250, 500 ${\mu}g/ml$ (p<0.01, respectively). Furthermore, at 48 h, 50, 100 or 200 nm MNP@$SiO_2$ decreased significantly cell viability at the concentration of 62.5 ${\mu}g/ml$ (p<0.05) and of 125, 250, 500 ${\mu}g/ml$ (p<0.01, respectively). Cellular location detected by confocal microscope represented they were existed in cytoplasm, mainly around cell membrane at 2 h after treatment of MNP@$SiO_2$. Treatment of 50 nm MNP@$SiO_2$ significantly increased DNA damage at middle and high dose (p<0.01), and treatment of 100 nm or 200 nm significantly increased DNA damage in all dose compared to control (p<0.01). Taken together, treatment of MNP@$SiO_2$ induced cytotoxicity and enhanced DNA damage in L5178Y cell.

• Molecular & Cellular Toxicology
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• v.5 no.2
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• pp.172-178
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• 2009

Nanoparticles are small-scale substances (<100 nm) with unique properties, complex exposure and health risk implications. Aluminum oxide ($Al_2O_3$) nanoparticles (NP) have been widely used as abrasives, wear-resistant coatings on propeller shafts of ships, to increase the specific impulse per weight of composite propellants used in solid rocket fuel and as drug delivery systems to increase solubility. However, recent studies have shown that nano-sized aluminum (10 nm in diameter) can generate adverse effects, such as pulmonary response. The cytotoxicity and genotoxicity of $Al_2O_3$ NP were investigated using the dye exclusion assay, the comet assay, and the mouse lymphoma thymidine kinase (tk$^{+/-}$) gene mutation assay (MLA). IC$_{20}$ values of $Al_2O_3$ NP in BEAS-2B cells were determined the concentration of 273.44 $\mu$g/mL and 390.63 $\mu$g/mL with and without S-9. However IC$_{20}$ values of $Al_2O_3$ NP were found nontoxic in L5178Y cells both of with and without S-9 fraction. In the comet assay, L5178Y cells and BEAS-2B cells were treated with $Al_2O_3$ NP which significantly increased 2-fold tail moment with and without S-9. Also, the mutant frequencies in the $Al_2O_3$ NP treated L5178Y cells were increased compared to the vehicle controls with S-9. The results of this study indicate that $Al_2O_3$ NP can cause primary DNA damage and cytotoxicity but not mutagenicity in cultured mammalian cells.