• 동의생리병리학회지
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• 제19권4호
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• pp.903-907
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• 2005

Many naturally occurring plant extracts are studied for their beneficial effects for health and particularly on cancer. Apoptosis, or programmed cell death, occurs in both normal and pathological conditions, including cancer Dysregulation of apoptosis allows transformed cells to continually and uninhibitedly enter the cell cycle, thus perpetuating the sequence of mutation, genomic instability and, finally, oncogenesis. To investigate the apoptosis-inducing effect of the extract of Fructus Trichosanthis (EFT) on leukemic HL-60 cells and its mechanism, HL-60 cells in vitro in culture medium were given different doses of the extract. The inhibitory rate of cells were measured by microculture tetrazolium assay, cell apoptotic rate was detected by flow cytometry, morphology of cell apoptosis was observed by DAPI fluorescence staining, and the activations of caspases and PARP were detected using Western blotting analysis. The extract could activate the caspase-3 and caspase-8, induce PARP cleavage, inhibit growth of HL-60 cells, and cause apoptosis significantly The suppression was in dose-dependent manner. Marked morphological changes of cell apoptosis including condensation of chromatin and nuclear fragmentation were observed clearly by DAPI fluorescence staining especially. These results will provide strong laboratory evidence of EFT for clinical treatment of acute leukemia.

• Biomolecules & Therapeutics
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• 제15권3호
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• pp.145-149
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• 2007

We have previously shown that 2,4,3',5'-tetramethoxystilbene (TMS), a synthetic trans-stilbene analogue acting as a potent inhibitor of human cytochrome P450 1B1, induces apoptotic cell death in human cancer cells. In the present studies, we report the mechanisms of apoptotic cell death by TMS in human promyelocytic leukemic HL-60 cells. We found that treatment of HL-60 cells with TMS suppressed the cell growth in a concentration-dependent manner with $IC_{50}$ value of about 0.8 ${\mu}M$. Immunoblot experiments revealed that DMHS-induced apoptosis was associated with cleavage of poly (ADP-ribose) polymerase. The release of cytochrome c from mitochondria into the cytosol was significantly increased in response to TMS. TMS caused activation of caspase-3 in a concentration-dependent manner and TMS-mediated caspase-3 activation was partially prevented by the caspase inhibitor, zVAD-fmk. Interestingly, we found that the cytotoxic effect of anticancer drugs such as paclitaxel, docetaxel, or etoposide was enhanced in the presence of TMS. Simultaneous treatment with TCDD also significantly increased cytotoxic effects of TMS alone or TMS and anti-cancer agents. Taken together, our present results indicated that TMS leads to apoptotic cell death in HL-60 cells through activation of caspase-3 activity and release of cytochrome c into cytosol. The ability of TMS to increase cytotoxic effect of anticancer drugs may contribute to its usefulness for cancer chemotherapy.

• 한국전통의학지
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• 제15권1호
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• pp.83-89
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• 2006

Many naturally occurring plant extracts are studied for their beneficial effects for health and particularly on cancer. Apoptosis, or programmed cell death, occurs in both normal and pathological conditions, including cancer. Dysregulation of apoptosis allows transformed cells to continually and uninhibitedly enter the cell cycle, thus perpetuating the sequence of mutation, genomic instability and, finally, oncogenesis. To investigate the apoptosis-Inducing effect of the extract of Fructus Trichosanthis (EFT) on leukemic HL-60 cells and its mechanism, HL-60 cells in vitro in culture medium were given different doses of the extract. The inhibitory rate of cells were measured by microculture tetrazolium assay, cell apoptotic rate was detected by flow cytometry, morphology of cell apoptosis was observed by DAPI fluorescence staining, and the activations of caspases and PARP were detected using Western blotting analysis. The extract could activate the caspase-3 and caspase-8, induce PARP cleavage, inhibit growth of HL-60 cells, and cause apoptosis significantly. The suppression was in dose-dependent manner. Marked morphological changes of cell apoptosis including condensation of chromatin and nuclear fragmentation were observed clearly by DAPI fluorescence staining especially. These results will provide strong laboratory evidence of EFT for clinical treatment of acute leukemia.

• 동의생리병리학회지
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• 제17권3호
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• pp.605-610
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• 2003

인삼, 호장근, 상산 등에서 분리한 성분들이 HL60, HL-60, Jurkat, Molt-4에 대한 억제작용이 있는 것으로 조사되었고, 익모초의 Leonunrine, 대청엽의 Indirubin, 천문동의 Aspargus polysaccharideA.B.C.D, 백합의 Colchicnamile, 익모초의 Lenunrine, 산두근, 자초근 추출물이 여러유형의 백혈병 환자에 대한 백혈병 억제효과가 있는 것으로 조사되었으며, mouse의 P388, L1210, L615, L120, S-180 등에 항 백혈병 효과가 있는 것으로는 완화, 로회, 원지, 오수유, 파두, 뇌공등, 석산, 백출, 단삼, 산약, 목단피, 청대, 감초, 당귀에서 분리한 성분들이 있으며 백굴채, 마전자, 가시오가피, 천초 추출물들이 동물실험에서 항암작용이 있는 것으로 조사되었다. 또 천연물에서 분리한 성분이 항백혈병 작용이 있는것으로는 ginsenoside Ro, ginseonoside Rh2, Emodin, Yuanhuacine, Aleemodin, phorbocdiester, Triptolide, Homolycorine, Atractylol, Colchicnamile, Paeonol, 당귀다당체, Aspargus polysaccharideABCD, Indirubin, Leonunrine, Acinosohic acid, Trichosanthin, G2 132, Schizandrin, allicin, Indirubin, cmdiumlactone chuanxiongol, 18A glycyrrhetic acid, Kansuiphorin A, 13 oxyingenol Kansuiphorin B 등이 조사되었고, 추출물이 항 백혈병 작용이 있는 것으로는 원지, 오수유, 백굴채, 대황, 산두근, 마전자, 가시오가피, 천초 등이 조사되었다.

• 동의생리병리학회지
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• 제19권2호
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• pp.452-458
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• 2005

Cordyceps militaris is a medicinal fungus, which has been used for patient suffering from cancer in Oriental medicine. It was reported previously that C. militaris extracts are capable of inhibiting tumor growth, however, the anti-poliferative effects of human cancer cells have not been poorly understood. In this study, to elucidate the growth inhibitory mechanisms of human cancer cells by treatment of aqueous extract of C. militaris (AECM) we investigated the anti-proliferative effects of AECM in human leukemia U937 cell line. AECM treatment inhibited the growth of U937 cells and induced the apoptotic cell death in a concentration-dependent manner, which was associated with morphological changes. We observed the up-regulation of cyclin-dependent kinase (Cdk) inhibitor p21(WAF1/CIP1) by p53-independent manner and activation of caspase-3 in AECM-treated U937 cells, however, the activity of caspase-9 was remained unchanged. Additionally, AECM treatment caused a dose-dependent inhibition of the expression of telomere regulatory gene products such as human telomere reverse transcriptase (hTERT) and telomerase-associated protein-1 (TEP-1). Taken together, these findings suggest that AECM-induced inhibition of human leukemic cell proliferation is associated with the induction of apoptotic cell death via modulation of several major growth regulatory gene products, and C. militaris may have therapeutic potential in human lung cancer.

• 한국동물학회지
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• 제34권4호
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• pp.469-478
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• 1991

The CALLA on the surface of leukemic cell lines, recognized by our monoclonal antibody. KP-22(IgG1, K) was one of cell surface glycoproteins having moi. wt. of approximately 100,000 dalton, and could be shed in spent medium or endocytosed when binding the cognate antidoby, KP-22. In the presence of cognate antibodies, 60% of CALLAS recogniEed by KP-22 MAs were modulated and cleared from the cell surface during 24 hrs, and approximaetely 35% of them was endocytosed and 25%, was shed in spent medium. The reappearance of the membrane CALLA after modulation by the KP-22 required at least 6 hours and supposed to be newly synthesized molecules.

• 약학회지
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• 제31권5호
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• pp.253-265
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• 1987

To develop hybridomas secreting monoclonal antibodies to be used as unlimited sources of reagents indispensable for the diagnosis and treatement of leukemic malignancy, a monoclonal antibody was generated to human pre-T leukemia cells (Jurkat). Hybridomas were produced against Jurkat cell line by fusing spleen cells from hyperimmunized mice with murine plasmacytoma cells (P3$\times$63Ag8. V653). One monoclonal antibody derived from this fusion, designated DMJ-2 was reactive with T-cell lines (Jurkat, Molt-4 and RPMI-8402) and normal peripheral E-rosette forming T cells, but unreactive with B-cell lines (Daudi, Nalm-6) and non-T, non-B cell line (K562). Conclusively DMJ-2 reactive with mature and immature T-lineage lymphoid cells.

• Asian Pacific Journal of Cancer Prevention
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• 제15권2호
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• pp.629-635
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• 2014

Background: Acute myeloid leukemia (AML) is a fatal hematological malignancy which is resistant to a variety of chemotherapy drugs. Myeloid cell leukemia-1 (Mcl-1), a death-inhibiting protein that regulates apoptosis, has been shown to be overexpressed in numerous malignancies. In addition, it has been demonstrated that the expression level of the Mcl-1 gene increases at the time of leukemic relapse following chemotherapy. The aim of this study was to target Mcl-1 by small interference RNA (siRNA) and analyze its effects on survival and chemosensitivity of acute myeloid leukemia cell line HL-60. Materials and Methods: siRNA transfection was performed with a liposome approach. The expression levels of mRNA and protein were measured by real-time quantitative PCR and Western blot analysis, respectively. Trypan blue assays were performed to evaluate tumor cell growth after siRNA transfection. The cytotoxic effects of Mcl-1 siRNA (siMcl-1) and etoposide were determined using MTT assay on their own and in combination. Apoptosis was quantified using a DNA-histone ELISA assay. Results: Transfection with siMcl-1 significantly suppressed the expression of Mcl-1 mRNA and protein in a time-dependent manner, resulting in strong growth inhibition and spontaneous apoptosis. Surprisingly, pretreatment with siMcl-1 synergistically enhanced the cytotoxic effect of etoposide. Furthermore, Mcl-1 down-regulation significantly increased apoptosis sensitivity to etoposide. No significant biological effects were observed with negative control siRNA treatment. Conclusions: Our results suggest that specific suppression of Mcl-1 by siRNA can effectively induce apoptosis and overcome chemoresistance of leukemic cells. Therefore, siMcl-1 may be a potent adjuvant in leukemia chemotherapy.

• 동의생리병리학회지
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• 제17권3호
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• pp.629-632
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• 2003

Scutellaria barbata has been used as a traditional Chinese Herb for treating liver, lung and rectal tumors. In the present study, cytotoxic effect of Scutellaria barbata MC fradtion was investigated and it was found to inhibit proliferation of human leukemic U937 cells with an IC50 of approximately 10 μg/ml in a dose-dependent manner. We also demonstrated that Scutellaria barbata MC fraction caused apoptosis in U937 cells. In the flow cytometric assay, the MC fraction-treated U937 cells showed an increase in hypo-diplold Sub G1 DNA contents. DNA fragmentation was observed by TUNEL assay. An increase of Bax:Bcl-2 ratio, activation of caspase-9, caspase-3, and cleavage of poly (ADP-ribose) polymerase (PARP) were demonstrated by western blot analysis. Taken together, these results exerted that the MC fraction suppressed human leukemic U937 cell proliferation by inducing apoptosis via the mitochondrial pathway.

• 대한핵의학회지
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• 제29권1호
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• pp.98-104
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• 1995

필자는 서울대학교 의과대학 병리학 교실에서 만든 항 백혈병 항체(항 CALLA 항체, 항 JL-1 항체)에 대해 $^{99m}Tc$과 $^{125}I$의 표지 방법 및 면역학적 성상을 연구하여 임상 응용의 토대를 만들고자 하였다. $^{99m}Tc$은 pretargeting transchelation법으로 $^{125}I$는 lodogen법으로 표지하였다. 각 항체에 대해 결합 반응검사, Scatchard 분석, 변조 현상 검사를 시행하였다. $^{125}I$는 두 항체 모두에서 90%전후의 높은 표지율을 보인 반면, $^{99m}Tc$ 경우 70%이하의 표지율을 보여 개선점이 요구되었다. 결합반응검사에서도 $^{99m}Tc$을 표지한 항체는 30%정도의 낮은 면역 반응성을 보였다. Scatchard 분석 결과 결합상수 모두가 $10^9$으로 좋은 친화력을 보였고, 세포당 항체 결합 수는 $10^4$으로 비교적 높은 농도로 나타났다. 변조 현상은 모든 경우에서 나타나지 않았다. 항 CALLA 항체, 항 JL-1 항체는 향후 림프종과 백혈병의 진단 및 치료에 도움이 될 수 있으리라 기대된다.