• Reproductive and Developmental Biology
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• 제30권4호
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• pp.263-270
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• 2006

The Chinese Hamster Ovarian cells CHO-K1 are one of the most extensively used cells for the evaluation of gene expression and toxicology. However, these cells are frequently used for biomedical research without consideration of their cytogenetic characteristics. Therefore, we carried out to investigate the karyologic profiles, the frequency and type of chromosome aberration, and the distribution of telomeric DNA on chromosomes of the CHO-K1 cells. The GTG banding and fluorescence in situ hybridization on CHO-K1 cells were performed to characterize the karyotype and the distribution of telomeric DNA The present study revealed that the chromosome modal number of CHO-K1 cells was 2n=20; eight chromosomes appeared to be identical with those of the normal Chinese hamster, whereas the remaining 12 chromosomes were shown to be translocated, deleted, inversed, or rearranged from Chinese hamster chromosomes. The telomeric DNA on CHO-K1 chromosomes was intensively distributed at the centromeres rather than the ends of chromosomes. In addition, three chromosomes had interstitial telomeres and one marker chromosome entirely consisted of telomeric DNAs. The frequency and type of chromosome aberrations in CHO-K1 cells were examined. Of the 822 metaphase spreads, 68 (8.3%) cells resulted in chromosome aberrations of which the chromosome breakage was the most frequently occurred.

• 생명과학회지
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• 제24권2호
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• pp.173-180
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• 2014

에스트로겐은 조직세포의 유형과 이들의 생리적 상태에 따라 세포증식을 촉진 또는 억제 시킬 수 있으며, 주로 에스트로겐 수용체(ER)에 의해 매개되는 신호전달 경로를 통해 작용한다. 이 연구는 특히 유방암세포에서 ER에 대한 길항제로 잘 알려진 fulvestrant (Ful)가 CHO 세포주의 증식 및 세포사멸에 미치는 영향과 이들에 대한 $17{\beta}$-estradiol (E2)의 작용에 미치는 효과를 조사하고자 하였다. 이를 위하여 먼저 다양한 농도의 E2, Ful 및 E2 plus Ful의 처리기간에 따라 세포증식에 미치는 효과를 조사하였다. Cell proliferation 분석에서, 6-10일의 처리기간 동안 E2는 1 ${\mu}M$의 농도까지는 세포증식에 영향을 주지 않았지만, 15-40 ${\mu}M$에서는 처리기간의 증가에 따라 점진적으로 현저히 세포증식을 억제하였다. 흥미롭게도 Ful 또한 1 ${\mu}M$의 농도까지는 세포증식에 영향을 주지 않았지만, 10-40 ${\mu}M$에서는 농도 및 시간 의존적인 세포증식 억제효과를 보였다. 뿐만 아니라, Ful은 10일 동안 E2와의 혼합처리에서 E2에 의한 세포증식 억제효과를 감소시키기 보다는 오히려 증대시켰다. 따라서 Ful은 CHO 세포에서 E2의 항 증식작용에 대한 길항적 효과를 갖지 않음을 제시한다. 한편, E2 및 Ful에 의한 DNA 분절효과를 확인하기 위한 TUNEL assay에서 20 ${\mu}M$의 E2로 처리된 CHO 세포주에서는 DAPI로 염색된 거의 모든 핵에서 TUNEL 양성반응이 나타났으며, 40 ${\mu}M$ Ful 및 20 ${\mu}M$ E2 plus 40 ${\mu}M$ Ful로 처리된 CHO 세포주에서는 TUNEL 양성반응을 보였으나, E2 처리군과 비교하여 현저히 낮은 비율로 나타났다. 이러한 결과는 Ful이 CHO 세포에서 E2의 항증식작용에 대한 길항적 효과를 갖지 않으며, E2와 Ful에 의한 세포증식 억제와 DNA 분절을 통한 세포사멸 관련기전은 다른 신호전달 경로를 통해 매개됨을 시사한다.

• The Korean Journal of Physiology and Pharmacology
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• 제27권1호
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• pp.31-38
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• 2023

Carboplatin, an advanced anticancer drug with excellent efficacy against ovarian cancer, was developed to alleviate the side effects that often occur with cisplatin and other platinum-based compounds. Our study reports the in vitro characteristics, viability, and activity of cells expressing the inducible nitric oxide synthase (iNOS) gene after carboplatin was conjugated with polysuccinimide (PSI) and administered in combination with other widely used anticancer drugs. PSI, which has promising properties as a drug delivery material, could provide a platform for prolonging carboplatin release, regulating its dosage, and improving its side effects. The iNOS gene has been shown to play an important role in both cancer cell survival and inhibition. Herein, we synthesized a PSI-carboplatin conjugate to create a modified anticancer agent and confirmed its successful conjugation. To ensure its solubility in water, we further modified the structure of the PSI-carboplatin conjugate with 2-aminoethanol groups. To validate its biological characteristics, the ovarian cancer cell line SKOV-3 and normal ovarian Chinese hamster ovary cells were treated with the PSI-carboplatin conjugate alone and in combination with paclitaxel and topotecan, both of which are used in conventional chemotherapy. Notably, PSI-carboplatin conjugation can be used to predict changes in the genes involved in cancer growth and inhibition. In conclusion, combination treatment with the newly synthesized polymer-carboplatin conjugate and paclitaxel displayed anticancer activity against ovarian cancer cells but was not toxic to normal ovarian cancer cells, resulting in the development of an effective candidate anticancer drug without severe side effects.

• Safety and Health at Work
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• 제2권1호
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• pp.17-25
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• 2011

Objectives: In this study, the in vitro mammalian chromosomal aberration (CA) assay was conducted to gain additional information concerning the hazards associated with the use of cyclopentane and ammonium nitrate. While these two chemicals had already been tested by many methods, they had not been studied in the CA test. Methods: The assay was performed using the ovarian infantile cell (CHO-K1 cell), by the direct method (-S9) and by the metabolic activated method (+S9 mix). Results: Using the direct method, the 7 dosages in a 48 hour treatment group did not show that the frequency of CA is proportion to the dosage addition. The frequency of CA is not proportion to the dosage addition for a 6 hour treatment using the metabolic activated method. Conclusion: From these findings, it was decided that the 2 chemicals do not induce chromosomal aberrations under the tested conditions.

• Journal of Microbiology and Biotechnology
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• 제29권2호
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• pp.304-310
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• 2019

Interleukin-21 is a common ${\gamma}$-chain cytokine that controls the immune responses of B cells, T cells, and natural killer cells. Targeting IL-21 to strengthen the immune system is promising for the development of vaccines as well as anti-infection and anti-tumor therapies. However, the practical application of IL-21 is limited by the high production cost. In this study, we improved IL-21 production by codon optimization and selection of appropriate signal peptide in CHO-K1 cells. Codon-optimized or non-optimized human IL-21 was stably transfected into CHO-K1 cells. IL-21 expression was 10-fold higher for codon-optimized than non-optimized IL-21. We fused five different signal peptides to codon-optimized mature IL-21 and evaluated their effect on IL-21 production. The best result (a 3-fold increase) was obtained using a signal peptide derived from human azurocidin. Furthermore, codon-optimized IL-21 containing the azurocidin signal peptide promoted $IFN-{\gamma}$ secretion and STAT3 phosphorylation in NK-92 cells similar to codon-optimized IL-21 containing original signal peptide. Collectively, these results indicate that codon optimization and azurocidin signal peptides provide an efficient approach for the high-level production of IL-21 as a biopharmaceutical.

• Asian-Australasian Journal of Animal Sciences
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• 제16권4호
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• pp.498-503
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• 2003

Luteinizing hormone as other glycoprotein hormones is characterized by a heterodimeric structure composed a common $\alpha$-subunit noncovalently linked to a specific $\beta$-subunit. The correct conformation of the heterodimer is important for efficient secretion, hormonal-specific post-translational modifications, receptor binding and signal transduction. To determine whether $\alpha$- and $\beta$- subunits can be synthesized as a single polypeptide chain (tethered-bLH and -bFSH) and also display biological activities, the tetheredbLH and -bFSH molecules were constructed and transfected into chinese hamster ovary (CHO-K1) cells. LH and FSH activities were assayed by using the human embryonic kidney (HEK) 293 cells expressing rat LH and FSH receptor genes. The tethered-bLH and - bFSH proteins were efficiently secreted and showed a similar activity to the dimeric bovine LH and FSH $\alpha$/$\beta$ wild type and native purified from bovine pituitary. The tethered-molecules can be permit development of potent new analogues that stimulate ovarian development. Taken together, a single-chain analog can also be constructed to include additional hormone-specific bioactive generating potentially efficacious compounds. These data indicate the potentiality of the single chain approach to further investigate structurefunction relationships of LH and FSH.

• Asian Pacific Journal of Cancer Prevention
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• 제14권5호
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• pp.3191-3196
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• 2013

Leaf extracts of Cassia alata L (akapulko), traditionally used for treatment of a variety of diseases, were evaluated for their potential antitumor properties in vitro. MTT assays were used to examine the cytotoxic effects of crude extracts on five human cancer cell lines, namely MCF-7, derived from a breast carcinoma, SK-BR-3, another breast carcinoma, T24 a bladder carcinoma, Col 2, a colorectal carcinoma, and A549, a nonsmall cell lung adenocarcinoma. Hexane extracts showed remarkable cytotoxicity against MCF-7, T24, and Col 2 in a dose-dependent manner. This observation was confirmed by morphological investigation using light microscopy. Further bioassay-directed fractionation of the cytotoxic extract led to the isolation of a TLC-pure isolate labeled as f6l. Isolate f6l was further evaluated using MTT assay and morphological and biochemical investigations, which likewise showed selectivity to MCF-7, T24, and Col 2 cells with $IC_{50}$ values of 16, 17, and 17 ${\mu}g/ml$, respectively. Isolate f6l, however, showed no cytotoxicity towards the non-cancer Chinese hamster ovarian cell line (CHO-AA8). Cytochemical investigation using DAPI staining and biochemical investigation using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-a method used to detect DNA fragmentation-together with caspase assay, demonstrated apoptotic cell death. Spectral characterization of isolate f6l revealed that it contained polyunsaturated fatty acid esters. Considering the cytotoxicity profile and its mode of action, f6l might represent a new promising compound with potential for development as an anticancer drug with low or no toxicity to non-cancer cells used in this study.

• Parasites, Hosts and Diseases
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• 제31권2호
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• pp.117-128
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• 1993

이 연구는 환자로부터 분리하여 무균 배양된 10개의 질트리코모나스 분리주에 대하여 병원성 여부를 판정하고 단백분해효소 관련 여부를 알아보고자 시도된 것이다. 질트리코모나스 분리주들은 마우스 피내 접종 실험을 통한 병원성 판정에서 약병원성 주, 중등도 병원성 주 및 강 병원성 주 등 3개 그룹으로 나눌 수 있었으며 중성 단백분해효소 및 산성 단백분해효소 활성도는 질트리코모나스 추출물 및 그 배양액에서 약 병원성 주에 비해 강 병원성 주의 활성도가 높게 나타나 피하농양 크기에 따른 병원성과 상기 단백분해효소의 비활성도(specific activi쇼) 사이에 상관관계가 있었음을 알 수 있었다(p < 0.05) 질트리코모나스 단백분해효소는 gelatin을 기질로 하는 SDS-PAGE 전기영동에서 RF치를 달리하는 5가지 분획대가 나타났으며 그 분획양상은 각 분리주 의 병원성에 따라 일정한 양상을 나타내었다. 그리고 여러가지 단백분해효소 억제제를 전기 영동 효소액에 처리했을 경우 antlpaln과 leupeptin 처리군에서는 분획이 전혀 나타나지 않았으며 EUTA 처리군에서는 대조군에 비해 그 활성이 약화된 분획이 관찰되었고, PMSF 처리군에서의 분획들은 대조군과 그 활성의 차이를 볼 수 없어 이들 단백 분해효소는 cystelne 단백분해효소로 추정되었다. 조직 세포에 대한 질트리코모나스 추출물의 세포독성은 병원성에 따라 차이가 있었고 추출물의 단백질 농도 $12.0{\;}\mu\textrm{g}/100{\mu}\ell$ 이상에서 세포 독성에 따른 병원성 구분이 용이하였다. 그리고 질트리코모나스 추출물에 단백분해효소 억제제를 처리한 결과 대조군에 비하여 세포 독성이 낮게 나타났으며, 특히 antipain 처리군에서는 조직 세포에 대한 세포 독성이 현저하게 낮았다. 이상의 결과로 보아 cysteine계로 추정되는 질트리코모나스의 단백분해효소는 특이한 전기영동 활성 분획상을 나타내었는 바 이들은 모두 충체의 병원성 및 세포 독성과 밀접한 관련이 있었다.

• Applied Microscopy
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• 제41권2호
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• pp.109-116
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• 2011

다낭성 난소증후군(polycystic ovary syndrome, PCOS)은 내분비 및 대사장애로 호르몬 불균형 상태를 야기하여 가임기 여성의 불임 및 여러 합병증을 유발한다. 폐경기 여성의 호르몬대체 치료에 사용되는 estradiol valerate (EV)는 과다 투여 시 PCOS를 유발하는 것으로 알려졌다. 신경성장인자(nerve growth factor, NGF)는 발생 중인 신경세포의 생존과 성숙을 조절하는 인자로 난소에서도 합성되고, EV 처리에 의해 유도된 다낭성난소(polycystic ovary, PCO)에서 발현이 크게 증가하는 것으로 보고됐다. 따라서 본 연구에서는 난소유래 세포인 CHO 세포주와 다낭성 난소를 이용해 호르몬 불균형 상태인 PCOS 진단 시 NGF가 생물학적 표지인자로서 사용될 수 있는 가능성을 규명하고자 하였다. CHO 세포에 EV 2 mg과 3 mg 처리는 초기에 세포증식을 억제했으나 1 mg 처리는 영향을 미치지 않음으로써 실험 시 최적농도로 사용하였다. 하지만 농도별 EV 처리에 따른 CHO 세포의 형태학적 차이는 관찰되지 않았다. CHO 세포에 EV 처리 후 NGF mRNA 및 단백질 발현은 대조군에 비해 30분 후 크게 증가하였고, 다수의 난포낭이 관찰된 PCOS 조직에서도 정상군에 비해 크게 증가하였다. 따라서 이상의 결과들을 종합하면 EV 처리 후 난소에서 유도되는 NGF 과발현은 비정상적 난포발달을 유도하는 인자로 작용할 것으로 보이며, 다낭성난소 진단 시 표지인자로서 사용될 수 있을 것으로 생각된다.