rIL-6抗癌机理初探—rIL-6对小鼠Mφ、LAK、NK、CTL细胞体内外调节效应

随着IL-6研究的日益深入，IL-6的抗癌效应研究越来越受到重视。为了进一步探讨IL-6对MΦ、LAK、NK、CTL细胞的调节效应，我们进行了rIL-6对小鼠MΦ、LAK、NK、CTL细胞调节效应的体内外实验研究，实验采用6～7周龄，体重为18—22g，雌性C57BL／6荷瘤(EL6)或正常小鼠，     

BCG—CW对荷瘤小鼠NK细胞杀伤活性及胸腺细胞增殖能力的影响

目的 探讨卡介苗细胞壁(BCG—CW)对荷瘤鼠脾脏NK细胞杀伤活性及胸腺细胞增殖能力的影响。方法 以小鼠脾脏NK细胞为效应细胞,以~3H—TdR标记的YAC—1细胞为靶细胞,测定NK细胞杀伤活性;胸腺细胞增殖能力采用~3H—TdR掺入法测定。结果 BCG—CW组和BCG—CW 5—Fu组荷瘤鼠脾脏NK细胞杀伤活性与肿瘤对照组比较,差异显著(P<0.05;P<0.001),而且在胸腺细胞增殖能力上也明显高于肿瘤对照组,并且与5—Fu组比较也有显著差异(P<0.001)。结论 BCG—CW对荷瘤鼠免疫系统有明显的调节作用,可增强荷瘤鼠NK细胞杀伤活性,促进小鼠胸腺细胞增殖能力。     

腺病毒介导IL-2基因转染的瘤苗体内抗肿瘤作用

目的 :探讨重组腺病毒介导的 IL- 2基因转染的瘤苗的体内抗肿瘤作用及其免疫学机制。方法 :应用腺病毒介导的鼠 IL- 2基因转染 CT2 6小鼠结肠癌细胞 ,灭活后用作瘤苗治疗荷瘤小鼠 ,观察皮下肿瘤生长及其存活期。采用乳酸脱氢酶释放法检测荷瘤小鼠脾细胞 CTL、L AK、NK细胞的杀伤活性。结果 :鼠 IL- 2基因转染瘤苗治疗能显著抑制荷瘤小鼠皮下肿瘤生长并明显延长其存活期 (P<0 .0 1)。体内免疫功能检测表明 ,鼠 IL- 2基因转染疫苗治疗组小鼠脾细胞 CTL 活性、L AK活性和 NK活性显著高于对照组 (P<0 .0 1)。结论 :腺病毒介导鼠 IL- 2基因转染的瘤苗体内具有较强的抗肿瘤效应 ,其机制可能是提高了荷瘤小鼠特异性和非特异性抗肿瘤免疫反应     

骨肉瘤患者外周血淋巴细胞体外相关瘤细胞致敏和rIL-2诱导的杀伤细胞

本实验对骨肉瘤患外周血淋巴细胞(PBL)采用2种培养方法；(1)PBL在体外用患肿瘤组织学相关传代骨肉瘤细胞(灭活处理)刺激5天再经rIL-2诱导12天；(2)单独rIL-2激活培养PBL3～5天；分别获取rIL-2诱导体外刺激细胞毒淋巴细胞(rIL-2-CL)和LAK细胞。借助^51Cr释放试验对2种效应细胞形成及体外抗瘤能力进行比较性研究。结论：rIL-2-CL主要是一种特异性较高，杀伤活性强烈CTL细胞群，对抗LAK细胞的骨肉瘤细胞具有明显杀伤效应。     

过继转输的肿瘤特异性T杀伤细胞在同系小鼠体内维持杀伤功能的研究

本实验采用Friend病毒在C56BL/6(B6)小鼠诱发的FBL-3红白血病细胞,按10~7细胞/ml加丝裂霉素C(MMC)100μg处理,用MMC灭活的FBL-3细胞经腹腔免疫B6小鼠(1×10~7/ml/只),两周后加强一次,2至6周内取脾脏。用这种免疫脾细胞在体外经肿瘤抗原刺激及低剂量rIL-2(5u/ml)作用,诱导和扩增以Lyt-2~ T细胞为主体的、抗FBL-3细胞的特异性Tc细胞。转输Tc细胞(2×10~7/每只鼠)到Cy预处理的同系正常小鼠或荷FBL-3白血病小鼠体内,观察不同因素对维持体内肿瘤特异性Tc细胞活性的影响。实验发现:(1)经肿瘤抗原刺激(转输T细胞时,即0天)和连续短程rIL-2(0.6天,3000U/天)处理正常同系转输小鼠,可使受鼠脾细胞对FBL-3细胞具有杀伤活性,以处理后第七天活性最高,而执行这一功能的是转输入体内的Lyt-2~ T细胞。对照组结果显示,转输正常脾细胞后经同样处理未诱导出对FBL-3细胞有明显杀伤活性的Tc细胞,说明受鼠脾细胞的杀伤活性主要是由转输入体内的供者T细胞所致,而非由于处理因素导致受鼠自身淋巴细胞被诱导激活所致;(2)单独给予rIL-2,即使延长使用时间(0-21天)也不能维持转输的Tc细胞在体内的活性。(3)间断抗原再刺激,联合应用7天rIL-2,以14天为一周期,可长期维持Tc细胞在体内的特异性杀伤功能,若间断单独使用     

酪丝亮肽对人肝癌BEL-7402细胞的抑制作用及对NK细胞杀伤活性的影响

[目的]研究三肽化合物酪丝亮肽(tyroserleutide,YSL)对人肝癌BEL-7402裸鼠移植瘤的抑制作用及对自然杀伤细胞(NK细胞)杀伤活性的影响。[方法]建立人肝癌BEL-7402裸鼠移植瘤模型,观察YSL对肿瘤生长的抑制作用;采用四甲基偶氮唑蓝(MTT)法检测YSL对正常小鼠及人肝癌BEL-7402荷瘤鼠的NK细胞杀伤活性的影响。[结果]YSL[160μg(/kg·d)]能抑制BEL-7402的生长,肿瘤抑制率为72.23%,且能增强BEL-7402荷瘤裸鼠及正常小鼠NK细胞杀伤活性,与生理盐水组相比均具有显著性差异(P<0.05)。[结论]YSL对人肝癌BEL-7402裸鼠移植瘤有抑制作用,并具有增强正常及荷瘤小鼠NK细胞杀伤肿瘤细胞活性的作用。     

骨肉瘤患者外周血淋巴细胞体外相关瘤细胞致敏和rIL-2诱导的杀伤细胞

本实验对骨肉瘤患者外周血淋巴细胞(PBL)采用2种培养方法:(1)PBL在体外用患者肿瘤组织学相关传代骨肉瘤细胞(灭活处理)刺激5天再经rIL-2诱导12天;(2)单独rIL-2,激活培养PBL3～5天;分别获取rIL-2诱导体外刺激细胞毒淋巴细胞(rIL-2-CL)和LAK细胞。借助~(51)Cr释放试验对2种效应细胞形成及体外抗瘤能力进行比较性研究。结论:rIL-2-CL主要是一种特异性较高,杀伤活性强烈CTL细胞群,对抗LAK细胞的骨肉瘤细胞具有明显杀伤效应。     

细胞毒T淋巴细胞治疗脑胶质瘤的实验研究

前文研究表明,榄香烯/丝裂霉素瘤苗在小鼠体内可诱导出杀伤G422瘤细胞很强的异源CTL,故选用CTL做脑内治疗胶质瘤实验.用微量注射器在小鼠右额叶直接穿刺,脑内注射G422细胞后第2天,再在原来穿刺部位分别注射CTL rIL-2,CTL,rIL-2,生理盐水(对照组)治疗.结果表明:单纯CTL治疗小鼠的生存期较rIL-2和对照组的生存期明显延长(P<0.005),CTL rIL-2较单纯CTL治疗明显延长且有长期生存(P<0.025).病理检查未见正常脑细胞损伤和残     

IL—2基因转染的肿瘤细胞增强机体免疫功能的实验研究

目的：探讨小鼠接种腺病毒介导的IL－2基因转移的CT26小鼠结肠腺癌细胞后机体免疫功能的变化（包括CTL、LAK细胞、NK细胞、巨噬细胞的杀伤活性变化）。方法：体外将腺病毒介导的小鼠IL－2基因转染CT26细胞（CT26-mIL-2)，然后将CT26－mIL2细胞接种于小鼠皮下。采用4h乳酸脱氢酸释放法检测荷瘤小鼠CTL、LAK、NK细胞的杀伤活性，MTT法检测巨噬细胞的杀伤活性。结果：接种CT26－mIL－2后第14d，小鼠脾细胞NK活性和诱导后的LAK活性和CTL活性均显著高于对照组（P＜0．01）；小鼠腹腔巨噬细胞数量显著增加，杀伤活性显著增强（P＜0．01）。结论：IL－2基因转染的肿瘤细胞能诱导机体的特异性和非特异性免疫功能参与机体的抗肿瘤作用。     

原癌基因与细胞凋亡

PJ-CW是新抗癌剂济南假单胞菌苗(PJV)的第二代制剂。本文总结了PJ-CW对荷瘤小鼠免疫功能调节的观察。结果显示,PJ-CW不仅能促进和调节荷瘤小鼠腹腔Mφ吞噬功能、CTL杀伤活性、NK活性和外周血ANAE~ 细胞数量以及人胎脾LAK细胞的杀伤活性,还能促进小鼠腹腔渗出细胞和淋巴细胞环核苷酸的含量,为PJ-CW的抗癌作用提供了实验依据。     

Irinotecan and radiation in vitro and in vivo

Loss of chromosome sequences at 13q14 (Rbl) and 17p13 (p53) associated with squamous cell carcinoma of head and neck (SCCHN) was evaluated in 12 recurrent tumors and 51 primary tumors from 63 patients. The incidence of LOH at 17p13 was 19 of 50 (38%) tumors, and at 13q14 was 21 of 57 (37%). LOH affecting Rbl and/or p53 was observed in 30 of 63 (48%) SCCHN. Coincident LOH at Rbl and p53 was detected in 10 of 46 (22%) tumors. There were nine cases in which primary and metastatic tumors were obtained from the same patient. Of these, seven were informative and five of these (71%) manifested LOH at p53 in both primary and metastatic sites. Examination of Rbl in these same tumors showed LOH in six of the nine metastases, and of these six, only three revealed LOH in the primary tumor. LOH at p53 or Rbl alone showed no correlation with clinical outcome. However, tumors that manifested LOH at both loci were associated with poorer patient outcome and poorer histological differentiation.     

Daunorubicin and daunorubicinol pharmacokinetics in plasma and tissues in the rat

Recent evidence suggests that 13-hydroxy metabolites of anthracyclines may contribute to cardiotoxicity. This study was designed to determine the pharmacokinetics of daunorubicin and the 13-hydroxy metabolite daunorubicinol in plasma and tissues, including the heart. Fisher 344 rats received 5 mg kg^–1 daunorubicin i.v. by bolus injection. Rats were killed at selected intervals for up to 1 week after daunorubicin administration for determination of concentrations of daunorubicin and daunorubicinol in the plasma, heart, liver, kidney, lung, and skeletal muscle. Peak concentrations of daunorubicin were higher than those of daunorubicinol in the plasma (133±7 versus 36±2 ng ml^–1;P<0.05), heart (15.2±1.4 versus 3.4±0.4 g g^–1;P<0.05), and other tissues. However, the apparent elimination half-life of daunorubicinol was longer than that of daunorubicin in most tissues, including the plasma (23.1 versus 14.5 h) and heart (38.5 versus 19.3 h). In addition, areas under the concentration/time curves (AUC) obtained for daunorubicinol exceeded those found for daunorubicin in almost all tissues, with the ratios being 1.9 in plasma and 1.7 in the heart. The ratio of daunorubicinol to daunorubicin concentrations increased dramatically with time from <1 at up to 1 h to 87 at 168 h in cardiac tissue. Thus, following daunorubicin injection, cumulative exposure (AUC) to daunorubicinol was greater than that to daunorubicin in the plasma and heart. If daunorubicinol has equivalent or greater potency than daunorubicin in causing impairment of myocardial function, it may make an important contribution to the pathogenesis of cardiotoxicity.     

TCP and NTCP in preclinical and clinical research in Europe

European research in radiation oncology has a long and successful tradition. The aim of this research is to increase the therapeutic window of radiotherapy by increasing the tumor control probability (TCP) and/or by decreasing the normal tissue complication probability (NTCP). This paper summarizes the basic radiobiological concept underlying treatment optimization by TCP-NTCP data and discusses some of the limitations of currently used models. These are controversial in many aspects and cannot be recommended for clinical routine practice but should rather be considered as a research tool.     

Foscan and foslip based photodynamic therapy in osteosarcoma in vitro and in intratibial mouse models

Current osteosarcoma therapies cause severe treatment‐related side effects and chemoresistance, and have low success rates. Consequently, alternative treatment options are urgently needed. Photodynamic therapy (PDT) is a minimally invasive, local therapy with proven clinical efficacy for a variety of tumor types. PDT is cytotoxic, provokes anti‐vascular effects and stimulates tumor cell targeting mechanisms of the immune system and, consequently, has potential as a novel therapy for osteosarcoma patients. This study investigated the uptake and the dark‐ and phototoxicity and cytotoxic mechanisms of the photosensitizer (PS) 5,10,15,20‐tetrakis(meta‐hydroxyphenyl) chlorine (mTHPC, Foscan) and a liposomal mTHPC formulation (Foslip) in the human 143B and a mouse K7M2‐derived osteosaroma cell line (K7M2L2) in vitro. Second, the tumor‐ and metastasis‐suppressive efficacies of mTHPC formulations based PDT and associated mechanisms in intratibial, metastasizing osteosarcoma mouse models (143B/SCID and syngeneic K7M2L2/BALB/c) were studied. The uptake of Foscan and Foslip in vitro was time‐ and dose‐dependent and resulted in mTHPC and light dose‐dependent phototoxicity associated with apoptosis. In vivo, the uptake of both i.v. administered mTHPC formulations was higher in tumor than in healthy control tissue. PDT caused significant (Foscan p < 0.05, Foslip p < 0.001) tumor growth inhibition in both models. A significant (Foscan p < 0.001, Foslip p < 0.001) immune system‐dependent suppression of lung metastasis was only observed in the K7M2L2/BALB/c model and was associated with a marked infiltration of T‐lymphocytes at the primary tumor site. In conclusion, mTHPC‐based PDT is effective in clinically relevant experimental osteosarcoma and suppresses lung metastasis in immunocompetent mice with beneficial effects of the liposomal mTHPC formulation Foslip.     

Hyperthermia and platinum complexes: Time between treatments and synergy in vitro and in vivo

To investigate the greatest therapeutic efficacy, we investigated the effect of scheduling on the cytotoxic interaction between hyperthermia and seven different platinum complexes in vitro and in vivo using the FSaII murine fibrosarcoma cells. Hyperthermia treatment (43°C, 1 h) was administered at various times relative to exposure of the cells to the IC₉₀ (at 37°C, 1 h) of each platinum complex. Greater-than-additive killing of FSaII cells was obtained with cis-diamminedichloroplatinum (II) (CDDP) and hyperthermia when the drug and heat exposure were overlapping or simultaneous. The same cell killing effect with carboplatin and hyperthermia resulted from heat exposure up to 5 h prior to, simultaneous with, or immediately after the drug exposure. D-Tetraplatin and K₂PtCl₄ were synergistic with hyperthermia only if the drug and heat exposure were simultaneous. PtCl₄(Nile Blue)₂ and hyperthermia produced greater-than-additive cell killing if the heat and drug exposure occurred in immediate sequence, simultaneously, or with drug exposure up to 5 h prior to heat exposure. PtCl₄(Rh-123)₂ and hyperthermia produced greater-than-additive cell killing if the drug and heat occurred in immediate sequence, overlapping, or simultaneously. PtCl₄(Fast Black)₂ and hyperthermia were additive over a wide range of scheduling from heat exposure 2 h prior to 5 h after drug exposure. When animals bearing FSaIIC tumours were treated with single doses of CDDP (10 mg/kg), carboplatin/PtCl₄(Nile Blue)₂ (50 mg/kg), PtCl₄(Rh-123)₂/PtCl₄(Fast Black)₂ (100 mg/kg) under various combined schedules with hyperthermia treatment (43°C, 30 min), similar cytotoxicity patterns were observed. To administer hyperthermia at a time when the drug concentration in the tumour tissue is at peak level, careful scheduling of systemically administered anticancer drugs with hyperthermia is needed. Modelling studies can identify the stringency/flexibility of drug/heat scheduling to achieve synergistic tumour cell killing.     

Fibronectin and integrins in invasion and metastasis

Summary The adhesive glycoprotein fibronectin and integrin receptors appear to play important roles in the progression of metastatic disease. Fibronectin is a multifunctional extracellular glycoprotein that has at least two independent cell adhesion regions with different receptor specificities. The cell adhesive region in the central portion of fibronectin is comprised of at least two minimal amino acid sequences - an Arg-Gly-Asp (RGD) sequence and a Pro-His-Ser-Arg-Asn (PHSRN) sequence - which function in synergy. Another cell adhesive region is located near the carboxy-terminus in the alternatively spliced IIICS module. The critical minimal sequences for this region are Leu-Asp-Val (LDV) and Arg-Glu-Asp-Val (REDV) which function in an additive rather than synergistic fashion. Integrins are heterodimeric, transmembrane cell adhesion receptors for fibronectin and other extracellular matrix molecules. Several different integrins bind to fibronectin. The ₅₁ fibronectin-specific integrin binds to the central RGD/PHSRN site. The ₄₁ integrin binds to the IIICS site. Fibronectin-integrin interactions are important in tumor cell migration, invasion, and metastasis. In addition to promoting cell adhesion to the extracellular matrix, these proteins may also function in chemotaxis and control of proliferation. Peptide and antibody inhibitors of fibronectin and integrin functions have been shown to be effective inhibitors of metastasis, and are potentially important reagents for the study and control of cancer.     

Racial Differences in Oral and Pharyngeal Cancer Treatment and Survival in Florida

OBJECTIVE: This study examined racial differences in treatment and survival for blacks and whites in Florida diagnosed with oral or pharyngeal cancer. METHODS: Data for 21,481 malignancies of the oral cavity or pharynx diagnosed from 1988 to 1998 were derived from the Florida Cancer Data System. Type of cancer treatment was compared by race, stratified by anatomic site and summary stage at diagnosis. Kaplan-Meier survival curves were used to compare survival rates and Cox regression models were used to estimate hazard ratios for race. Covariates included age, sex, census tract income, and treatment. RESULTS: Stratifying by tumor site and stage, blacks consistently had poorer survival rates than whites. Across tumor stages, blacks with oral cavity cancer were consistently more likely than whites to have received only radiotherapy and less likely to have received cancer-directed surgery. Trends were similar for pharyngeal cancer, although statistically significant only for regional stages. Across site and stage, blacks consistently had elevated hazard ratios (range: 1.20-1.53) relative to whites. CONCLUSIONS: In Florida, there were racial differences in patient treatment for oral or pharyngeal cancer. Blacks had lower survival rates than whites, but differences in treatment did not entirely account for racial disparities in survival.     

Synergistic anti-cancer effects of immunotoxin and cyclosporin in vitro and in vivo

Background:

The clinical use of immunotoxins (ITs) has been hampered by hepatotoxicity, and the induction of a strong human-anti-IT response. The human-anti-IT response results in neutralisation of the immunoconjugates, rendering repetitive treatment inefficacious.

Methods:

We evaluated the combination of cyclosporin A (CsA) with various Pseudomonas exotoxin A-based ITs in human breast, cervical, and prostate cancer cell lines measured by protein synthesis, cell viability, and TUNEL assay. Furthermore, expression of essential proteins were analysed by western blot. We used cervical cancer model in nude rats to evaluate the anti-metastatic effect of the combination. The anti-immunogenic response by the CsA treatment was investigated in immunocompetent rats.

Results:

The combination of CsA with ITs caused remarkable synergistic cytotoxicity, in several cancer cell lines, characterised by protein synthesis inhibition, decreased cell viability, and an increased apoptotic index. Furthermore, the combination strongly inhibited formation of metastases in a cervical cancer model in nude rats with a statistically significant increase in median survival time of the combination-treated animals, as compared with those receiving a suboptimal dose of IT alone. Notably, we found in immunocompetent rats that the anti-IT immunoresponse elicited by repeated administration of IT was efficiently abrogated by CsA; notably the antibody responds towards the highly immunogenic PE was shown to be prevented.

Conclusion:

The combination of ITs and CsA might constitute a significant improvement in the clinical potential of systemic IT treatment of cancer patients.