Synergistic therapeutic effect of arsenic trioxide and radiotherapy in BALB/C nude mice bearing nasopharyngeal carcinoma xenografts

It has been shown that arsenic trioxide (ATO) induced apoptosis in human nasopharyngeal carcinoma cells and inhibited the growth of nasopharyngeal carcinoma xenografts (NPCX) in nude mice. Aim: The present study was designed to determine whether ATO at the non-toxic dose level could potentiate the t...

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Veröffentlicht in:Experimental Oncology
Datum:2007
Hauptverfasser: Xie, L.X., Lin, X.H., Li, D.R., Chen, J.Y., Hong, C.Q., Du, C.W.
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Veröffentlicht: Інститут експериментальної патології, онкології і радіобіології ім. Р.Є. Кавецького НАН України 2007
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Zitieren:Synergistic therapeutic effect of arsenic trioxide and radiotherapy in BALB/C nude mice bearing nasopharyngeal carcinoma xenografts / L.X. Xie, X.H. Lin, D.R. Li, J.Y. Chen, C.Q. Hong, C.W. Du // Experimental Oncology. — 2007. — Т. 29, № 1. — С. 45-48. — Бібліогр.: 18 назв. — англ.

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Digital Library of Periodicals of National Academy of Sciences of Ukraine
id nasplib_isofts_kiev_ua-123456789-138563
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spelling Xie, L.X.
Lin, X.H.
Li, D.R.
Chen, J.Y.
Hong, C.Q.
Du, C.W.
2018-06-19T09:33:45Z
2018-06-19T09:33:45Z
2007
Synergistic therapeutic effect of arsenic trioxide and radiotherapy in BALB/C nude mice bearing nasopharyngeal carcinoma xenografts / L.X. Xie, X.H. Lin, D.R. Li, J.Y. Chen, C.Q. Hong, C.W. Du // Experimental Oncology. — 2007. — Т. 29, № 1. — С. 45-48. — Бібліогр.: 18 назв. — англ.
1812-9269
https://nasplib.isofts.kiev.ua/handle/123456789/138563
It has been shown that arsenic trioxide (ATO) induced apoptosis in human nasopharyngeal carcinoma cells and inhibited the growth of nasopharyngeal carcinoma xenografts (NPCX) in nude mice. Aim: The present study was designed to determine whether ATO at the non-toxic dose level could potentiate the therapeutic effectiveness of radiation therapy in nasopharyngeal carcinoma, using a BALB/C nude mouse xenograft model. Methods: The mice bearing NPCX were treated with radiation alone (2, 4, and 6 Gy), ATO alone (4 mg/kg/day x 6 days), and ATO plus radiation at the same dosage levels. Time of tumor growth delay (defined as the time necessary for the tumor to grow four-fold of its initial volume after, compared with untreated tumors) and toxic effects were determined. Results: The low dose ATO alone has no pronounced effects on tumor growth delay compared to untreated control. However, compared with radiation alone, the combined regimen delayed the tumor growth by 2–10 days and had no significant toxic effects such as the liver function damage. Conclusions: Combination of ATO at non-toxic dose level and radiation has synergistic effects on tumor growth inhibition in vivo and is well tolerated.
Установлено, что триоксид мышьяка (ТОМ) индуцирует апоптоз в клетках карциномы носоглотки человека и ингибирует рост ксенографта карциномы носоглотки у атимических мышей. Цель работы — установить терапевтическую эффективность радиотерапии в комбинации ТОМ в нетоксичной дозе мышам линии BALB/ с ксенографтом карциномы носоглотки. Методы: животные с ксенографтом карциномы носоглотки получали либо только радиотерапию (2, 4 и 6 Гр) или ТОМ (4 мг/кг/день в течение 6 дней), или их комбинацию в тех же режимах и дозах. Задержку роста опухоли определяли как различие во времени, необходимом для достижения опухолью 4-кратного объема по сравнению с начальным объемом в опытной группе versus такового в контрольной группе. Результаты: введение ТОМ в низкой дозе не оказывало выраженного влияния на рост опухоли по сравнению с показателями в конт­рольной группе, а в комбинации с облучением приводило к задержке роста опухоли на 2–12 сут по сравнению с показателями у животных, получавших только лучевую терапию при отсутствии выраженных побочных эффектов. Выводы: комбинация ТОМ в нетоксической дозе и лучевой терапии приводит к ингибированию роста опухоли in vivo и не вызывает побочных эффектов. Ключевые слова: триоксид мышьяка, радиотерапия, ксенографт карциномы носоглотки.
This work was supported by the Shantou University Research and Development grant (L03002), the Traditional Chinese Medicine Research grant of Guangdong Province (102053), China.
en
Інститут експериментальної патології, онкології і радіобіології ім. Р.Є. Кавецького НАН України
Experimental Oncology
Original contributions
Synergistic therapeutic effect of arsenic trioxide and radiotherapy in BALB/C nude mice bearing nasopharyngeal carcinoma xenografts
Синергичный терапевтический эффект триоксида мышьяка и радиотерапии у мышей линии BALB/C с ксенографтами карциномы носоглотки
Article
published earlier
institution Digital Library of Periodicals of National Academy of Sciences of Ukraine
collection DSpace DC
title Synergistic therapeutic effect of arsenic trioxide and radiotherapy in BALB/C nude mice bearing nasopharyngeal carcinoma xenografts
spellingShingle Synergistic therapeutic effect of arsenic trioxide and radiotherapy in BALB/C nude mice bearing nasopharyngeal carcinoma xenografts
Xie, L.X.
Lin, X.H.
Li, D.R.
Chen, J.Y.
Hong, C.Q.
Du, C.W.
Original contributions
title_short Synergistic therapeutic effect of arsenic trioxide and radiotherapy in BALB/C nude mice bearing nasopharyngeal carcinoma xenografts
title_full Synergistic therapeutic effect of arsenic trioxide and radiotherapy in BALB/C nude mice bearing nasopharyngeal carcinoma xenografts
title_fullStr Synergistic therapeutic effect of arsenic trioxide and radiotherapy in BALB/C nude mice bearing nasopharyngeal carcinoma xenografts
title_full_unstemmed Synergistic therapeutic effect of arsenic trioxide and radiotherapy in BALB/C nude mice bearing nasopharyngeal carcinoma xenografts
title_sort synergistic therapeutic effect of arsenic trioxide and radiotherapy in balb/c nude mice bearing nasopharyngeal carcinoma xenografts
author Xie, L.X.
Lin, X.H.
Li, D.R.
Chen, J.Y.
Hong, C.Q.
Du, C.W.
author_facet Xie, L.X.
Lin, X.H.
Li, D.R.
Chen, J.Y.
Hong, C.Q.
Du, C.W.
topic Original contributions
topic_facet Original contributions
publishDate 2007
language English
container_title Experimental Oncology
publisher Інститут експериментальної патології, онкології і радіобіології ім. Р.Є. Кавецького НАН України
format Article
title_alt Синергичный терапевтический эффект триоксида мышьяка и радиотерапии у мышей линии BALB/C с ксенографтами карциномы носоглотки
description It has been shown that arsenic trioxide (ATO) induced apoptosis in human nasopharyngeal carcinoma cells and inhibited the growth of nasopharyngeal carcinoma xenografts (NPCX) in nude mice. Aim: The present study was designed to determine whether ATO at the non-toxic dose level could potentiate the therapeutic effectiveness of radiation therapy in nasopharyngeal carcinoma, using a BALB/C nude mouse xenograft model. Methods: The mice bearing NPCX were treated with radiation alone (2, 4, and 6 Gy), ATO alone (4 mg/kg/day x 6 days), and ATO plus radiation at the same dosage levels. Time of tumor growth delay (defined as the time necessary for the tumor to grow four-fold of its initial volume after, compared with untreated tumors) and toxic effects were determined. Results: The low dose ATO alone has no pronounced effects on tumor growth delay compared to untreated control. However, compared with radiation alone, the combined regimen delayed the tumor growth by 2–10 days and had no significant toxic effects such as the liver function damage. Conclusions: Combination of ATO at non-toxic dose level and radiation has synergistic effects on tumor growth inhibition in vivo and is well tolerated. Установлено, что триоксид мышьяка (ТОМ) индуцирует апоптоз в клетках карциномы носоглотки человека и ингибирует рост ксенографта карциномы носоглотки у атимических мышей. Цель работы — установить терапевтическую эффективность радиотерапии в комбинации ТОМ в нетоксичной дозе мышам линии BALB/ с ксенографтом карциномы носоглотки. Методы: животные с ксенографтом карциномы носоглотки получали либо только радиотерапию (2, 4 и 6 Гр) или ТОМ (4 мг/кг/день в течение 6 дней), или их комбинацию в тех же режимах и дозах. Задержку роста опухоли определяли как различие во времени, необходимом для достижения опухолью 4-кратного объема по сравнению с начальным объемом в опытной группе versus такового в контрольной группе. Результаты: введение ТОМ в низкой дозе не оказывало выраженного влияния на рост опухоли по сравнению с показателями в конт­рольной группе, а в комбинации с облучением приводило к задержке роста опухоли на 2–12 сут по сравнению с показателями у животных, получавших только лучевую терапию при отсутствии выраженных побочных эффектов. Выводы: комбинация ТОМ в нетоксической дозе и лучевой терапии приводит к ингибированию роста опухоли in vivo и не вызывает побочных эффектов. Ключевые слова: триоксид мышьяка, радиотерапия, ксенографт карциномы носоглотки.
issn 1812-9269
url https://nasplib.isofts.kiev.ua/handle/123456789/138563
citation_txt Synergistic therapeutic effect of arsenic trioxide and radiotherapy in BALB/C nude mice bearing nasopharyngeal carcinoma xenografts / L.X. Xie, X.H. Lin, D.R. Li, J.Y. Chen, C.Q. Hong, C.W. Du // Experimental Oncology. — 2007. — Т. 29, № 1. — С. 45-48. — Бібліогр.: 18 назв. — англ.
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first_indexed 2025-11-24T18:45:28Z
last_indexed 2025-11-24T18:45:28Z
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fulltext Experimental Oncology ���� ������� ����� ��arc��� ������ ������� ����� ��arc��� ���arc��� ���� �� �� It �as been well known t�at radiation t�erapy �RT�� is one of t�e major effective treatments for nasop�a- ryngeal carcinoma. However�� due to t�e �ig� dose of radiation�� patients frequently suffer from toxic effects�� suc� as xerostomia�� �earing loss�� �ypomnesia�� dys- p�agia [1]�� neck stiffness [�]�� and nasal synec�ia [3]. T�ere is an urgent need for novel approac�es to im- proving response of cancer cells to radiation t�erapy. Unfortunately�� effective non-toxic radiosensitizers for clinical use are �ard to find. Arsenic trioxide �ATO�� �as been reported as an ef- fective agent in t�e treatment of patients wit� leukemia [��6]. Recently�� several studies �ave been focused on t�e antitumor effects of ATO on solid tumors [���11]. It �as been reported t�at ATO en�anced radiation response in glioma [��� �]�� cervical cancer [1�]�� �ead and neck squamous cell carcinomas [11]. In our previous studies�� we demonstrated several potential mec�anisms by w�ic� ATO reduced t�e invasive and metastatic properties of nasop�aryngeal carcinoma cells�� including G�/� arrest�� up-regulation of p�3 and Bax expression�� and down-regulation of Bcl-� expression [1��� 13]. In addition�� we found t�at ATO en�anced radiosensitivity of nasop�aryngeal carci- noma cells in vitro [13]. T�us�� it is reasonable to de- termine w�et�er ATO can increase radiation response of nasop�aryngeal carcinoma in vivo. T�e aims of our present study are to determine t�e t�erapeutic effects of ATO�� RT�� and combination of t�e bot� treatments on nasop�aryngeal carcinoma in vivo�� to detect t�e toxic effects of t�e combined treatment�� if any�� and to evalu- ate t�e potential benefits for future clinical use. MATERIALS AND METHODS Test compound and reagents. ATO was pur- c�ased from Harbin-Eda P�armaceutical Co. Ltd�� C�i- na. Ot�er reagents are t�e �ig�est grade available. Animal model and treatment. BALB/C mice�� ���� weeks of age and weig�ing 1���� g�� were ob- tained from t�e Experimental Animal Center of Sun Yat-Sen �edical University �Guang Z�ou�� C�ina��. T�e current study was approved by t�e Et�ic Committee of Cancer Hospital�� S�antou University. T�e mice were raised under SPF �specific pat�ogen free�� condition. Human nasop�aryngeal carcinoma cell line�� CSNET-1�� was used in t�e experiment. It is a poorly differentiated squamous cell carcinoma�� usually maintained in a frozen state�� and �as been proven to be transplantable in severe combined immunodeficiency �SCID�� mice [1�]. Before experiment�� 1�6 exponentially growing cancer cells were inoculated subcutaneously into t�e back of several Balb/c nude mice. W�en tumors reac� approximately � mm in lengt� diameter�� t�ey were obtained by surgical resection�� minced wit� scissors into fragments of about 1 mm in diameter and t�en implanted subcutaneously into t�e armpit of BALB/C mice. W�en tumors were palpable �~ � mm in lengt� diameter���� mice were randomly divided into several groups: one untreated control�� t�ree groups treated wit� radiation alone �RT���� one ATO alone �ATO���� and t�ree groups wit� ATO plus radiation �ATO + RT��. RT and ATO + RT groups were treated wit� single radiation of ��� ��� and 6 Gy�� respectively. T�ere were � mice in eac� group. ATO �� mg/kg per day�� was administered i. p. for 6 days. In t�e combined treratment�� after t�e last ATO treatment�� local irradiation of ��� � or 6 Gy was delivered SYNERGISTIC THERAPEUTIC EFFECT OF ARSENIC TRIOXIDE AND RADIOTHERAPY IN BALB/C NUDE MICE BEARING NASOPHARYNGEAL CARCINOMA XENOGRAFTS L.X. Xie1, X.H. Lin2, D.R. Li1, *, J.Y. Chen1, C.Q. Hong1, C.W. Du1 1Laboratory of Cancer Research, Tumor Hospital, Shantou University Medical College, Shantou, China 2Department of Biomedical Engineering, School of Engineering and Applied Science, Washington University, Saint Louis, USA It has been shown that arsenic trioxide (ATO) induced apoptosis in human nasopharyngeal carcinoma cells and inhibited the growth of nasopharyngeal carcinoma xenografts (NPCX) in nude mice. Aim: The present study was designed to determine whether ATO at the non-toxic dose level could potentiate the therapeutic effectiveness of radiation therapy in nasopharyngeal carcinoma, using a BALB/C nude mouse xenograft model. Methods: The mice bearing NPCX were treated with radiation alone (2, 4, and 6 Gy), ATO alone (4 mg/kg/day x 6 days), and ATO plus radiation at the same dosage levels. Time of tumor growth delay (defined as the time necessary for the tumor to grow four-fold of its initial volume after, compared with untreated tumors) and toxic effects were determined. Results: The low dose ATO alone has no pronounced effects on tumor growth delay compared to untreated control. However, compared with radiation alone, the combined regimen delayed the tumor growth by 2–10 days and had no significant toxic effects such as the liver function damage. Conclusions: Combination of ATO at non-toxic dose level and radiation has synergistic effects on tumor growth inhibition in vivo and is well tolerated. Key Words: arsenic trioxide, radiation, nasopharyngeal carcinoma xenografts. Received: February 7, 2007. *Correspondence: Fax: +86-754-8560352 E-mail: liderui2007@yahoo.com.cn Abbreviations used: ALT — alanine aminotransferase; AST — as- partate aminotransferase; ATO — arsenic trioxide; RT — radiation therapy. Exp Oncol ����� ���� 1�� ����� �6 Experimental Oncology ���� ������� ����� ��arc��� wit� an X-ray mac�ine �Tape 1T1-V�� Beijing�� C�ina���� ope- rating at 1�� KV�� 1� mA�� �.� mm Cu-equivalent filter�� wit� a dose rate of 1���.3cGy/min. During irradiation�� unanest�etized mice were placed and fixed in speciallymice were placed and fixed in specially designed Perspex boxes�� isolated from t�e air�� and t�e and t�e normal tissue around t�e tumor was s�ielded as muc� as possible by placing some lead coverings upon t�e surface of t�e boxes. Measurement of tumor growth. Tumor size was measured wit� vernier calipers�� and tumor volume was calculated by t�e formula a × b�/� �a is t�e maximal dia- meter�� b is t�e minimal diameter�� [1�]. T�e measure- ment was performed daily after inoculation of tumor�� and weekly after radiation. Relative tumor volume wasRelative tumor volume was determined by taking t�e initial volume before radiation as 1. T�e time needed for a xenograft to reac� �-fold. T�e time needed for a xenograft to reac� �-fold of its initial volume was defined as TGT�. Time of tumor growt� delay �TGD�� was t�e TGT� w�en compared wit� t�e control group�� e. g. TGD of RT group compared wit� untreated group�� TGD of RT + ATO group compared wit� RT alone group. Detection of toxic effect. In all experiments�� mice were monitored daily for signs of toxicity. OnOn t�e ��t� week after radiation�� w�en t�e relative volume of tumor in eac� group reac�ed � times of t�e initial volume�� t�e mice were sacrificed. T�en t�e blood sam- ples were collected. Examination of serum aspartateaspartate aminotransferase �AST�� and alanine aminotransferase �ALT�� levels were performed using an automated bio- c�emistry mac�ine �Olympus�� Japan�� for evaluation of t�e toxic effects on liver function. After mice were sac- rificed�� t�e toxic effects of t�erapy on t�e state of �eart�� lungs�� liver�� kidneys were detected �istologically. Additional 1� mice were treated using t�e same regimen as in t�e group treated wit� ATO alone to evaluate t�e acute toxic effects. Statistical analysis. T�e results of TGD�� AST�� and ALT analyses were expressed as t�e mean ± standard deviation. T�e Student’s t-test was used to determine t�e significance of t�e differences among t�e treated groups compared wit� controls. A p- value of < �.�� was considered statistically significant. RESULTS Tumor response to the combined treatment of ATO and radiation. On t�e 1�t� day after t�e implanta- tion of nasop�aryngeal carcinoma xenograft in mice�� ��% of tumors were palpable �> � mm in lengt� diame- ter��. On t�e �t� week after radiation t�erapy�� or t�e �3t� day after tumor implantation�� tumors in eac� group grew more t�an �-fold compared wit� t�at before ra- diation. T�ere was no obvious c�ange in weig�t�� signs of life�� activity among various treatment groups. T�e TGT�’s in t�e ATO alone group and t�e untreated group were �.� ± �.�� and �.� ± �.�� days�� respectively �p = �.������ indicating t�at ATO treatment alone �ad no impact on tumor growt�. In addition�� at t�e dose used in t�e present study�� ATO �ad no �ost toxicity�� t�erefore considering t�is dose as a non-toxic dose. However�� compared wit� t�at of RT alone group�� t�e tumor growt� delay by radiation was significantly en�anced by ATO in a dose-dependent manner w�en combined wit� t�e non-toxic doses of ATO. As s�own in Table 1�� w�en t�e relative tumor volume reac�ed ��� t�e tumor growt� delay from t�e combined treatment wit� ATO and RT was estimated to be about � �� Gy���� 13 �� Gy���� and �1 days �6 Gy���� respectively�� after t�e effects of ATO were deducted from t�e results�� significantly greater t�an t�at from RT alone �p < �.���� �Figure��. Table 1���� Tumor growth delay in experimental animals treated by RT alone and combined treatment with ATO and RT RT dose Tumor growth delay (days) RT alone ATO + RT p value 2 Gy 1.9 ± 0.6 3.9 ± 1.3 < 0.05 4 Gy 7.6 ± 1.8 13 ± 2.4 < 0.05 6 Gy 11.9 ± 2.9 21.7 ± 4.4 < 0.05 Figure. T�e effects of combined treatment wit� ATO and radiation on nasop�aryngeal carcinoma xenografts in BALB/C nude mice Evaluation of AST and ALT. No significant diffe- rences in t�e levels of AST and ALT between control group and group wit� combined treatment by RT and ATO were observed �p > �.������ suggesting t�at t�e combined treatment was well tolerated in t�e experimental animals �Table ���. Table 2�� AST and ALT levels in untreated group of animals and combined treatment group Groups Results of liver function test AST U/L ALT U/L Untreated RT + ATO (2 Gy) RT + ATO (4 Gy) RT + ATO (6 Gy) Control for toxic effect 40.1 ± 24.8 37.8 ± 32.4 37.3 ± 34.3 41.3 ± 35.1 47.3 ± 21.4 196.3 ± 45.6 174.7 ± 49.7 169.5 ± 52.3 178.2 ± 40.2 201.2 ± 25.5 There are no significant difference between the treated group and untreated group (p > 0.5). �oreover�� no obvious toxic c�anges were found �is- tologically in liver�� lung�� kidney�� and �eart tissue�� and no metastases were not found as well. T�ere were no differ- ences in t�e toxicity among various treatment groups. DISCUSSION Some recent studies �ave indicated t�at ATO mig�t en�ance radiation response in some solid tumors [���11�� 16]�� and t�e combined treatment wit� ATO and fractionated radiot�erapy are effective in t�e treat- ment of relapsed acute promyelocytic leukemia [1��]�� but t�ere are no in vivo data supporting its effect in nasop�aryngeal carcinoma. Hig� dose of radiation alone or ATO alone was required to treat nasop�aryngeal carcinoma effec- Experimental Oncology ���� ������� ����� ��arc��� ������� ������� ����� ��arc��� ����arc��� ����� ��� ��� tively�� but some pat�ological c�anges in liver and cardiac tissues were found [1�]. In t�e current study�� TGT� was used to determine t�e treatment effect�� t�us�� t�e radiation doses used in t�e current study s�ould enable all t�e xenografts to reac� � times of t�eir initial volumes and s�ould not cause tumor disappearance after irradiation. T�at is w�y we c�ose relatively low radiation doses �� Gy�� � Gy�� 6 Gy�� for t�e experiment. Before t�e drug administration�� we performed several preliminary experiments to determine t�e dose of ATO. T�ree doses ���� ���� and 1� mg/kg�� were used�� t�e ATO doses at �� and 1� mg/kg could lead to severe toxicity including deat�. In contrast�� no mice died at t�e dose of � mg/kg�� indicating t�at low dose of ATO caused less toxic effects. �oreover�� ATO alone at t�e dose of � mg/kg �ad no pronounced antitumor ef- fect compared wit� t�e untreated controls. T�erefore t�e combination treatment wit� low dose of ATO may �ave clinical implication. Our results s�owed t�at t�e combined treatment wit� ATO and radiation delayed tumor growt� significantly�� suggesting t�e synergistic effects between ATO and radiation. To determine t�e time for tumor growt� delay w�en t�e relative tumor volume reac�ed � times of t�e initial tumor size�� t�e data for ATO alone as control was de- ducted�� t�us t�e in�ibitory effect of tumor growt� by combined ATO and RT s�owed t�e synergistic effects. As s�own in Table 1�� TGD of ATO combined wit� RT was �ig�er t�an t�at of RT alone�� w�ic� was dependent on t�e dose of radiation. T�ese results �ave demonstrated en�ancement of radiation response by ATO in naso- p�aryngeal carcinoma in vivo�� and furt�er confirmed our previous results in vitro [13]. Considering t�at liver disfunction is a major adverse event of ATO in clinical treatment of leukemia [1�]�� we investigated t�e effects of combined treatment wit� ATO and RT on t�e level of AST and ALT in mice. To our knowl- edge�� t�is is t�e first report on toxic effects of ATO on liver function in solid tumor models. We used two groups of animals for combined treatment�� one was sacrificed s�ortly after t�e last time of drug administration�� anot�er one was sacrificed by t�e end of t�e experiments. No significant difference in t�e levels of AST and ALT was found among t�e two groups and t�e untreated group�� indicating t�at no obvious liver disfunction was caused by t�e combined treatment. �oreover�� no significant toxic effects eit�er by observation of activity�� weig�t or pat�ological morp�ology�� indicating t�e combination wit� ATO and RT was a well tolerable treatment. In conclusion�� low dose of ATO en�ances t�e response of nasop�aryngeal carcinoma to radia- tion t�erapy in nude mouse xenograft models w�ic� provides a basis for future studies wit� t�is combined regimen in patients wit� nasop�aryngeal carcinoma ACkNOwLEDGEMENT T�is work was supported by t�e S�antou University Researc� and Development grant �L�3������� t�e Tradi- tional C�inese �edicine Researc� grant of Guangdong Province �1����3���� C�ina. REFERENCES 1. Wu Y, Hu WH, Xia YF, Ma J, Liu MZ, Cui NJ. Quality of life of nasopharyngeal carcinoma survivors in Mainland China. Qual Life Res 2006; 16: 65–74. 2. Fang FM, Chiu HC, Kuo WR, Wang CJ, Leung SW, Chen HC, Sun LM, Hsu HC. Health-related quality of life for nasopharyngeal carcinoma patients with cancer-free survival af- ter treatment. Int J Radiat Oncol Biol Phys 2002; 53: 959–68. 3. Chen Y, Huang G, Huang Z, Wen W, Xie C. 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СИНЕРГИЧНЫЙ� �ЕР��Е��ИЧЕС�ИЙ� ���Е�� �РИ��СИ�� �ЕР��Е��ИЧЕС�ИЙ� ���Е�� �РИ��СИ���ЕР��Е��ИЧЕС�ИЙ� ���Е�� �РИ��СИ�� ���Е�� �РИ��СИ�����Е�� �РИ��СИ�� �РИ��СИ���РИ��СИ�� МЫШЬЯ�� И Р��И��ЕР��ИИ �� МЫШЕЙ� �ИНИИ BALB/C И Р��И��ЕР��ИИ �� МЫШЕЙ� �ИНИИ BALB/CИ Р��И��ЕР��ИИ �� МЫШЕЙ� �ИНИИ BALB/C Р��И��ЕР��ИИ �� МЫШЕЙ� �ИНИИ BALB/CР��И��ЕР��ИИ �� МЫШЕЙ� �ИНИИ BALB/C �� МЫШЕЙ� �ИНИИ BALB/C�� МЫШЕЙ� �ИНИИ BALB/C МЫШЕЙ� �ИНИИ BALB/CМЫШЕЙ� �ИНИИ BALB/C �ИНИИ BALB/C�ИНИИ BALB/C BALB/C С �СЕН�ГР����МИ ��Р�ИН�МЫ Н�С�Г����И �СЕН�ГР����МИ ��Р�ИН�МЫ Н�С�Г����И�СЕН�ГР����МИ ��Р�ИН�МЫ Н�С�Г����И ��Р�ИН�МЫ Н�С�Г����И��Р�ИН�МЫ Н�С�Г����И Н�С�Г����ИН�С�Г����И Установлено, что триоксид мышьяка (ТОМ) индуцирует апоптоз в клетках карциномы носоглотки человека и ингибирует рост ксенографта карциномы носоглотки у атимических мышей. Цель работы — установить терапевтическую эффектив- ность радиотерапии в комбинации ТОМ в нетоксичной дозе мышам линии BALB/C с ксенографтом карциномы носоглотки.BALB/C с ксенографтом карциномы носоглотки./C с ксенографтом карциномы носоглотки.C с ксенографтом карциномы носоглотки. с ксенографтом карциномы носоглотки. Методы: животные с ксенографтом карциномы носоглотки получали либо только радиотерапию (2, 4 и 6 Гр) или ТОМ (4 мг/кг/день в течение 6 дней), или их комбинацию в тех же режимах и дозах. �адержку роста опухоли определяли какв течение 6 дней), или их комбинацию в тех же режимах и дозах. �адержку роста опухоли определяли как 6 дней), или их комбинацию в тех же режимах и дозах. �адержку роста опухоли определяли как различие во времени, необходимом для достижения опухолью 4-кратного объема по сравнению с начальным объемом в опытной группе versus такового в контрольной группе. Результаты: введение ТОМ в низкой дозе не оказывало выраженного влияния на рост опухоли по сравнению с показателями в контрольной группе, а в комбинации с облучением приводило к задержке роста опухоли на 2–12 сут по сравнению с показателями у животных, получавших только лучевую терапию при отсутствии выраженных побочных эффектов. Выводы: комбинация ТОМ в нетоксической дозе и лучевой терапии приводит к ингибированию роста опухоли in vivo vivovivo и не вызывает побочных эффектов. Ключевые слова: триоксид мышьяка, радиотерапия, ксенографт карциномы носоглотки. Copyright © Experimental Oncology, 2007