• Title/Summary/Keyword: doxorubicin cytotoxicity

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Effects of Non-Cytotoxic Concentration of Anticancer Drugs on Doxorubicin Cytotoxicity in Human Breast Cancer Cell Lines

  • Lee, Yoon-Ik;Lee, Young-Ik
    • BMB Reports
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    • v.29 no.4
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    • pp.314-320
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    • 1996
  • The effects of non-cytotoxic concentrations of tamoxifen, verapamil, and trifluoperazine on doxorubicin cytotoxicity in five human breast cancer cell lines were studied. A non-cytotoxic concentration of tamoxifen resulted in enhanced doxorubicin cytotoxicity in HTB-123, HTB-26, and MCF-7. In these three cell lines, a combination of tamoxifen with verapamil resulted in even more increased doxorubicin cytotoxicity. Addition of verapamil or trifluoperazine alone did not influence the doxorubicin cytotoxicity significantly. Only in HTB-19 did coincubation with verapamil increase the doxorubicin cytotoxicity. In HTB-123, combination of tamoxifen with trifluoperazine increased the doxorubicin cytotoxicity significantly. In the cell lines where co-incubation with tamoxifen increased doxorubicin sensitivity, high estrogen receptor expression was detected. However, HTB-20, where tamoxifen did not enhance doxorubicin action, was also estrogen receptor positive. None of the cell lines had multidrug resistance related drug efflux and drug retention was not increased by the treatment with tamoxifen and verapamil. Cell cycle traverses were not altered by incubation with tamoxifen, verapamil or combinations thereof. These observatlons suggest mechanism of non-cytotoxic concentrations of tamoxifen and verapamil on doxorubicin cytotoxicity may involve one or more other cellular processes besides those of interference of estrogen binding to its receptor, cell cycle perturbation, or drug efflux blocking.

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C-terminal truncated HBx reduces doxorubicin cytotoxicity via ABCB1 upregulation in Huh-7 hepatocellular carcinoma cells

  • Jegal, Myeong-Eun;Jung, Seung-Youn;Han, Yu-Seon;Kim, Yung-Jin
    • BMB Reports
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    • v.52 no.5
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    • pp.330-335
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    • 2019
  • Hepatitis B virus (HBV) encoding the HBV x protein (HBx) is a known causative agent of hepatocellular carcinoma (HCC). Its pathogenic activities in HCC include interference with several signaling pathways associated with cell proliferation and apoptosis. Mutant C-terminal-truncated HBx isoforms are frequently found in human HCC and have been shown to enhance proliferation and invasiveness leading to HCC malignancy. We investigated the molecular mechanism of the reduced doxorubicin cytotoxicity by C-terminal truncated HBx. Cells transfected with C-terminal truncated HBx exhibited reduced cytotoxicity to doxorubicin compared to those transfected with full-length HBx. The doxorubicin resistance of cells expressing C-terminal truncated HBx correlated with upregulation of the ATP binding cassette subfamily B member 1(ABCB1) transporter, resulting in the enhanced efflux of doxorubicin. Inhibiting the activity of ABCB1 and silencing ABCB1 expression by small interfering ribonucleic acid (siRNA) increased the cytotoxicity of doxorubicin. These results indicate that elevated ABCB1 expression induced by C-terminal truncation of HBx was responsible for doxorubicin resistance in HCC. Hence, co-treatment with an ABCB1 inhibitor and an anticancer agent may be effective for the treatment of patients with liver cancer containing the C-terminal truncated HBx.

Increases in Doxorubicin Sensitivity and Radioiodide Uptake by Transfecting shMDR and Sodium/Iodide Symporter Gene in Cancer Cells Expressing Multidrug Resistance (다약제내성 암세포에서 shMDR과 Sodium/Iodide Symporter 유전자의 이입에 의한 Doxorubicin 감수성과 방사성옥소 섭취의 증가)

  • Ahn, Sohn-Joo;Lee, Yong-Jin;Lee, You-La;Choi, Chang-Ik;Lee, Sang-Woo;Yoo, Jeong-Soo;Ahn, Byeong-Cheol;Lee, In-Kyu;Lee, Jae-Tae
    • Nuclear Medicine and Molecular Imaging
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    • v.41 no.3
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    • pp.209-217
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    • 2007
  • Purpose: Multidrug resistance (MDR) of the cancer cells related to mdr1 gene expression can be effectively treated by selective short hairpin RNA for mdr1 gene (shMDR). Sodium/iodide symporter (NIS) gene is well known to have both reporter and therapeutic gene characteristics. We have co-transfected both shMDR and NIS gene into colon cancer cells (HCT15 cell) expressing MDR and Tc-99m sestamibi and I-125 uptake were measured. In addition, cytotoxic effects of doxorubicin and I-131 therapy were also assessed after transfection. Material and Methods: At first, shMDR was transfected with liposome reagent into human embryonic kidney cells (HEK293) and HCT cells. shMDR transfection was confirmed by RT-PCR and western blot analysis. Adenovirus expressing NIS (Ad-NIS) gene and shMDR (Ad-shMDR) were co-transfected with Ad-NIS into HCT15 cells. Forty-eight hours after infection, inhibition of P-gycoprotein (Pgp) function by shMDR was analyzed by a change of Tc-99m sestamibi uptake and doxorubicin cytotoxicity, and functional activity of induced NIS gene expression was assessed with I-125 uptake assay. Results: In HEK293 cells transfected with shMDR, mdr1 mRNA and Pgp protein expressions were down regulated. HCT15 cells infected with 20 MOI of Ad-NIS was higher NIS protein expression than control cells. After transfection of 300 MOI of Ad-shMDR either with or without 10 MOI of Ad-NIS, uptake of Tc-99m sestamibi increased up to 1.5-fold than control cells. HCT15 cells infected with 10 MOI of Ad-NIS showed approximately 25-fold higher I-125 uptake than control cells. Cotransfection of Ad-shMDR and Ad-NIS resulted in enhanced cytotoxic by doxorubicin in HCT15 cells. I-131 treatment on HCT15 cells infected with 20 MOI of Ad-NIS revealed increased cytotoxic effect. Conclusion: Suppression of mdr1 gene expression, retention of Tc-99m sestamibi, enhanced doxorubicin cytotoxicity and increases in I-125 uptake were achieved in MDR expressing cancer cell by co-transfection of shMDR and NIS gene. Dual therapy with doxorubicin and radioiodine after cotransfection shMDR and NIS gene can be used to overcome MDR.

Cytotoxicity and Apoptosis of Various Concentrations of Doxorubicin in Methylcholanthrene- induced Rat Fibrosarcoma(MCA) Cells (Methylcholanthrene 유도 섬유육종세포주에서 Doxorubicin 농도에 따른 세포독성과 자멸사의 변화)

  • 정진용;왕영필;나석주
    • Journal of Chest Surgery
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    • v.34 no.6
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    • pp.447-453
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    • 2001
  • Background: Although pulmonary resection is the standard approach for the management of pulmonary metastases from soft tissue sarcoma, most of them are unresectable and chemotherapy remains the only option. The effectiveness of the cytotoxic drugs may be limited by the toxicities that occur before the therapeutic dose is reached. The regional administration of doxorubicin using pulmonary arterial perfusion in a rodent model can produce 10 to 25 times higher concentrations in the lung than systemic administration with minimal systemic toxicities. However, it is unclear whether a high concentration of doxorubicin has beneficial effects for killing cancer cells. Material and Method: We studied this to evaluate the dose-dependent cytotoxic and apoptotic effects of doxorubicin on methylcholanthrene-induced rat fibrosarcoma(MCA) cells. This study examined the cytotoxicity and apoptosis-related gene expressions(Fas, FasL, Bax, caspase 1, caspase 2, caspase 8, Bcl-2, Bcl-xL, Bcl-xS) in MCA cells after 24 hours exposure to various concentrations of doxorubicin such as 1, 5, 10, 50, and 100 $\mu$M. Result: Dose-dependent cytotoxicity was observed after 24 hours exposure to doxorubicin. However, peak apoptosis after 24 hours exposure was observed at 5 $\mu$M of doxorubicin. Above 5 $\mu$M, apoptotic activity was decreased with dose-increment. All mRNA levels of apoptosis-related genes after 24 hours exposure were up-regulated above the control level at 1 $\mu$M of doxorubicin and then decreased by doxorubicin dose-increment except caspase 8, which showed higher levels than the control level at 5 $\mu$M. Apoptosis-related protein levels were highest at 1 $\mu$M of doxorubicin and then decreased by doxorubicin dose-increment. However, Bax and Bcl-xL proteins steadily showed higher levels than the control throughout the different concentrations of doxorubicin. Conclusion: These results suggest that apoptosis is the main cytotoxic mechanism in low concentrations of doxorubicin in MCA cells and apoptosis-related genes, such as Bax, caspase 8, and Bcl-xL, are involved. At high concentrations, doxorubicin still can kill MCA cells, even when apoptosis is inhibited, and have its propriety for achieving much cytotoxicity against MCA cells.

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