• 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 Analysis Health and Toxicology
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• v.14 no.1_2
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• pp.1-12
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• 1999

Recently, several new methods for the detection of genetic damages in vitro and in vivo based on molecular biological techniques were introduced according to the rapid progress in toxicology combined with cellular and molecular biology. Among these methods, mouse lymphoma thymidine kanase (tk) gene forward mutation assay, single cell gel electrophoresis (comet assay) and transgenic animal and cell line model as a target gene of lac I (Big Blue) and lac Z (Muta Mouse) gene mutation are newly introduced based on molecular toxicological approaches. The mouse lymphoma tk$\^$+/-/ gene assay (MOLY) using L5178Y tk$\^$+/-/ mouse lymphoma cell line is one of the mammalian forward mutation assays, and has many advantages and more sensitive than hprt assay. The target gene of MOLY is a heterozygous tk$\^$+/-/ gene located in 11 chromosome, 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. The comet assay is a rapid, simple, visual and sensitive technique for measuring and analysing DNA breakages in mammalian cells, Also, transgenic animal and cell line models, which have exogenous DNA incorporated into their genome, carry recoverable shuttle vector containing reporter genes to assess endogenous effects or alteration in specific genes related to disease process, are powerful tools to study the mechanism of mutation in vivo and in vitro, respectively. Also in vivo acridine orange supravital staining micronucleus assay by using mouse peripheral reticulocytes was introduced as an alternative of bone marrow micronucleus assay. In this respect, there was an International workshop on genotoxicity procedure (IWGTP) supported by OECD and EMS (Environmental Mutagen Society) at Washington D. C. in March 25-26, 1999. The objective of IWGTP is to harmonize the testing procedures internationally, and to extend to finalization of OECD guideline, and to the agreement of new guidelines under the International Conference of Harmonization (ICH) for these methods mentioned above. Therefore, we introduce and review the principle, detailed procedure, and application of MOLY, comet assay, transgenic mutagenesis assay and supravital staining micronucleus assay.

• Korean Journal of Veterinary Research
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• v.63 no.3
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• pp.30.1-30.8
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• 2023

Metformin is a treatment used widely for non-insulin-dependent diabetes mellitus with few side effects and acts by inhibiting hepatic gluconeogenesis and glucose absorption from the gastrointestinal tract. Lymphoma is one of the most common hematological malignancies in dogs. Chemotherapy is used mainly on lymphoma, but further research on developing anticancer drugs for lymphoma is needed because of its severe side effects. This study examined the anticancer effects of metformin alone and in combination with 2-deoxy-D-glucose (2-DG), a glucose analog, on EL4 cells (mouse T cell lymphoma). Metformin reduced the metabolic activity of EL4 cells and showed an additive effect when combined with 2-DG. In addition, cell death was confirmed using a trypan blue exclusion test, Hochest 33342/propidium iodide (PI) staining, and Annexin V/PI staining. An analysis of the cell cycle and mitochondria membrane potential (MMP) to investigate the mechanism of action showed that metformin stopped the G2/M phase of EL4 cells, and metformin + 2-DG decreased MMP. Metformin exhibited anticancer effects as a G2/M phase arrest mechanism in EL4 cells and showed additive effects when combined with 2-DG via MMP reduction. Unlike cytotoxic chemotherapeutic anticancer drugs, metformin and 2-DG are related to cellular glucose metabolism and have little toxicity. Therefore, metformin and 2-DG can be an alternative to reduce the toxicity caused by chemotherapeutic anticancer drugs. Nevertheless, research is needed to verify the in vivo efficacy of metformin and 2-DG before they can be used in lymphoma treatments.

• Journal of Life Science
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• v.11 no.2
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• pp.99-102
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• 2001

Mouse malignant T-lymphoma CS21 cells can grow when cocultured with CAl2 lymph node stromal cells, but they undergo apoptotic cell death with DNA fragmentation when separated from CA12 stromal cells. In the course of examining the effects of the soluble factor (s) secreted by CAl2 stromal cells on CS2l cell growth, we found that thiols including cysteine promoted CS2l cell growth. P388 cell growth was also promoted by various thiols. These results suggest that thiols including cysteine participate in CA12 and P388 cell growth.

• Biomedical Science Letters
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• v.9 no.3
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• pp.111-121
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• 2003

Recombinant single chain Fv (scFv) antibodies offer many advantages over mouse monoclonal antibodies such as faster clearance from blood, improved tumor localization, reduced human anti-mouse antibody (HAMA) response, and the availability to manipulate the scFv through genetic approaches. The recombinant phage display was constructed using lym-l hybridoma cells as a source of genetic starting material. mRNA was isolated from the corresponding antibodies hybridoma cells. VH and VL cDNA were amplified with RT-PCR and linked with ScFv by linker DNA to form ScFv DNA, which then were inserted into phagemid pCANTAB5E. The phage of positive clones selected with tube containing raji lymphoma cell and infected by competent E. coli HB2151 to express soluble scFv. The scFv lym-l was secreted into the cytosol and culture supernatant and shown to be of expected size (approximately 32 kDa) by western blot. An active scFv lym-l could be produced in E. coli with soluble form and high yield from hybridoma cell line, using phage display system. Immunoreactivity indicated that scFv lym1 showed a potential biding affinity against the raji lymphoma cell as its parental antibody (intact lym-l Ab).

• 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.20 no.3
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• pp.212-217
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• 1997

Induction of an adaptive response to ionizing radiation in mouse lymphoma (EL4) cells was studied by using cell survival fraction and apoptotic nucleosomal DNA fragmentation as biological end points. Cells in early log phase were pre-exposed to low dose of ${\gamma}$-rays (0.01 Gy) 4 or 20 hrs prior to high dose ${\gamma}$-ray (4, 8 and 12 Gy for cell survival fraction analysis; 8 Gy for DNA fragmentation analysis) irradiation. Then cell survival fractions and the extent of DNA fragmentation were measured. Significant adaptive response, increase in cell survival fraction and decrease in the extent of DNA fragmentation were induced when low and high dose .gamma.-ray irradiation time interval was 4 hr. Addition of protein or RNA synthesis inhibitor, cycloheximide or 5,6-dichloro-1-.betha.-d-ribofuranosylbenzimidazole (DRFB), respectively during adaptation period, the period from low dose ${\gamma}$-ray irradiation to high dose ${\gamma}$-ray irradiation, was able to inhibit the induction of adaptive response, which is the reduction of the extent DNA fragmentation in irradiated EL4 cells. These data suggest that the induction of adaptive response to ionizing radiation in EL4 cells required both protein and RNA synthesis.

• Molecules and Cells
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• v.38 no.3
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• pp.251-258
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• 2015

Germline mutations in the breast cancer type 2 susceptibility gene (BRCA2) are linked to familial breast cancer and the progressive bone marrow failure syndrome Fanconi anaemia. Established Brca2 mouse knockout models show embryonic lethality, but those with a truncating mutation at the C-terminus survive to birth and develop thymic lymphoma at an early age. To overcome early lethality and investigate the function of BRCA2, we used T cell-specific conditional Brca2 knockout mice, which were previously shown to develop thymic lymphoma at a low penetrance. In the current study we showed that the number of peripheral T cells, particularly na$\ddot{i}$ve pools, drastically declined with age. This decline was primarily ascribed to improper peripheral maintenance. Furthermore, heterozygous mice with one wild-type Brca2 allele manifested reduced T cell numbers, suggesting that Brca2 haploinsufficiency might also result in T cell loss. Our study reveals molecular events occurring in Brca2-deficient T cells and suggests that both heterozygous and homozygous Brca2 mutation may lead to dysfunction in T cell populations.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.2083-2087
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• 2016

A new compound namely (13-(3,3-dihydroxypropyl)-1,6-dihydroxy-3,4-dihydro-1H-isochromen-8(5H)-one (1) was isolated from an ethyl acetate extract of the borne fungi Screlotium rolfsii. Its chemical structure was elucidated by spectroscopic analysis. Screlotiumol 1 were evaluated for their effects on the reversion of multidrug resistant (MDR) mediated by P-glycoprotein (P-gp) of the soil borne fungi. The multidrug resistant P-glycoprotein is a target for chemotherapeutic drugs in cancer cells. In the present study rhodamine-123 exclusion screening test on human mdr1 gene transfected mouse gene transfected L5178 and L5178Y mouse T-cell lymphoma which showed excellent MDR reversing effect in a dose dependent manner against mouse T-lymphoma cell line. Moreover, molecular docking studies of compound-1 also showed better results as compared with the standard. Therefore the preliminary results obtained from this study suggest that screlotiumol 1 could be used as a potential agent for the treatment of cancer.

• IMMUNE NETWORK
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• v.5 no.1
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• pp.11-15
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• 2005

Background: Throughtout the last three decades, the therapy of leukemias and lymphoma has set the stage for curative cancer therapy in systemic malignant disease. This was the result of an integrated work of basic reaserch and clinical investigators leading to more aggressive albeit tolerable protocol of chemotherapy and radiotherapy. High dose therapy marks the most elaborated strategies in this field today. However, intensification of conventional therapeutic modalities as mentioned has to be based on new approaches and the exploration of new antineoplastic mechanisms. This insight has resulted in immune therapy of cancer. Among the cells of the immune system, natural killer (NK) cells and T cells are of major interest for the development of therapeutic strategies. Methods: Cytotoxicity to target cells was measured by LDH release method, Characterization of activated lymphocyte was measured by Flow cytometry analysis. Anti-CD3, 16, 56 monoclonal antibody and IL-2 were used for the activation of NK and T cell. The analysis of effect of activated lymphocyte, in vivo, were used by Balb/c nude mouse. Results and Conclusion: Cytotoxicity to K562 cells was significantly higher in the mixture group of NK and T cells than that of a group of activating T cells. The survivors and the rate of reduction of size of tumor craft of nude mouse group treatment with activated lymphocyte was higher than that of the group without treatment with activated lymphocyte. Therefore, this results are suggested that the activated lymphocytes by anti-CD3, CD16 and CD56 can reduce the malignancy effect of lymphoma.