促红细胞生成素对达卡巴嗪抗小鼠黑色素瘤细胞活性的调节作用

目的检测小鼠黑色素瘤细胞株B16促红细胞生成素受体(Erythropoietin receptor,EPOR)的表达,探讨促红细胞生成素(Erythropoietin,EPO)对达卡巴嗪抗B16细胞活性的影响及与Bcl-2家族蛋白表达的关系。方法采用RT-PCR、免疫荧光和激光共聚焦显微镜、Western blot等方法检测B16 细胞EPOR mRNA和蛋白的表达。MTT法和克隆形成试验检测EPO与达卡巴嗪联合应用时对B16细胞增殖的影响。Western blot法检测EPO对B16细胞Bcl-2、Bcl-xL、Bax蛋白表达的影响。结果B16细胞表达EPOR mRNA和蛋白。EPO能有效减少达卡巴嗪诱导B16细胞的凋亡（P<0.05）,EPO作用后,B16细胞Bcl-2、Bcl-xL蛋白表达水平明显增加（P<0.05）,Bax蛋白表达水平未见明显变化。结论B16细胞表达EPOR,EPO可调节化疗药对B16细胞的作用,其作用机制可能与其影响Bcl-2家族蛋白表达有关。     

促红细胞生成素对达卡巴嗪和顺铂抗小鼠黑色素瘤活性的调节作用

目的：研究促红细胞生成素（erythropoietin,EPO）对荷黑色素瘤小鼠肿瘤生长的影响及其对达卡巴嗪（dacarbazine,DTIC）和顺铂（cisplatin,DDP）抗肿瘤活性的调节作用。方法：将荷黑色素瘤B16细胞的C57BL/6小鼠,分别用EPO、DTIC和DDP以及EPO分别联合DTIC、DDP药物处理,以盐水处理组为对照。观察肿瘤在小鼠体内的生长情况。部分小鼠于停药次日摘除眼球取血,分析血液中红细胞（RBC）、血红蛋白（Hb）、红细胞压积（Hct）和白细胞（WBC）水平。并颈椎脱臼处死小鼠,剥离瘤体,分别称量瘤质量。其余小鼠用于生存期观察。结果：EPO处理组小鼠的肿瘤体积和质量与盐水处理组相比差异无统计学意义（P〉0.05）;DTIC联合EPO处理组小鼠的肿瘤体积和质量与DTIC处理组相比差异无统计学意义（P〉0.05）;DDP联合EPO处理组小鼠的肿瘤体积与DDP处理组相比明显缩小（P〈0.05）。应用EPO处理组的小鼠外周血RBC、Hb和Hct水平明显高于未应用EPO组（P〈0.05）。结论：EPO对黑色素瘤细胞在小鼠体内的生长没有明显影响;但EPO能调节黑色素瘤细胞对DTIC、DDP的敏感性,且该调节作用与化疗药的类型有关。     

重组人血管内皮抑制素联合达卡巴嗪增强抗黑素瘤作用及其机制研究

目的:探讨重组人血管内皮抑制素(recombinant human endostatin, rh-endostatin)联合达卡巴嗪(Dacarbazine)能否增强抗黑素瘤作用,并初步分析其作用机制.方法:分别采用MTT法和FCM法检测重组人血管内皮抑制素单药及其联合达卡巴嗪对黑素瘤B16F10细胞增殖和凋亡的影响;Western印迹法检测重组人血管内皮抑制素对黑素瘤细胞中细胞外信号调节激酶(extracellular signal-regulated kinase,ERK)磷酸化的影响;建立C57BL/6黑素瘤荷瘤小鼠模型,研究重组人血管内皮抑制素联合达卡巴嗪能否增强体内抗黑素瘤的作用.结果:重组人血管内皮抑制素、达卡巴嗪以及两药联合处理对黑素瘤B16F10细胞增殖的抑制率分别为(9.67±2.89)%、(22.67±3.06)%和(30.33±1.16)%,差异有统计学意义(P<0.05);重组人血管内皮抑制素组黑素瘤细胞的ERK分子磷酸化水平明显降低.接种肿瘤18 d时,重组人血管内皮抑制素组、达卡巴嗪组和两药联合组荷瘤小鼠的肿瘤体积分别为(6.45±1.24)cm3、(8.94±2.04)cm3和(4.56±0.98)cm3,两药联合组的肿瘤体积明显低于达卡巴嗪单药组(P<0.05).结论:重组人血管内皮抑制素联合达卡巴嗪体外可增强抗黑素瘤B16F10细胞增殖的作用,体内可增强达卡巴嗪对荷瘤小鼠黑素瘤生长的抑制作用,并提高荷瘤小鼠的存活率.推测抑制黑素瘤细胞中ERK分子酪氨酸磷酸化可能是重组人血管内皮抑制素发挥其抗黑素瘤作用的机制之一.     

MITF基因扩增预测重组人血管内皮抑素联合达卡巴嗪一线治疗晚期黑色素瘤疗效的临床研究

目的 探讨小眼畸形相关转录因子（MITF）基因扩增对重组人血管内皮抑素（恩度）联合达卡巴嗪一线治疗晚期黑色素瘤的疗效预测作用。方法 收集60例接受恩度联合达卡巴嗪一线治疗晚期黑色素瘤患者的石蜡包埋组织样本,采用实时定量PCR检测MITF基因扩增,观察患者的疾病控制率和远期疗效。结果 56例晚期黑色素瘤样本成功检测,MITF基因扩增率为51.8％（29／56）,其中肢端、非肢端皮肤、黏膜、原发不明黑色素瘤中的MITF基因扩增率分别为31.2％、63.2％、80.0％和36.4％（P=0.050）。MITF基因扩增组与无扩增组患者接受恩度联合达卡巴嗪治疗的疾病控制率分别为58.6％（17／29）和81.5％（22／27）,差异无统计学意义（P=0.063）;两组的中位无进展生存期分别为6.4个月（95％CI：0.5～12.2个月）和8.4个月（95％CI：6.8～10.3个月）,差异亦无统计学意义（P=0.169）。结论 中国晚期黑色素瘤患者MITF基因扩增率较高,检测MITF基因扩增可能有助于预测恩度联合达卡巴嗪治疗晚期黑色素瘤的疗效,总生存结果有待进一步随访。     

抑瘤素M与肿瘤生长

抑瘤素Ｍ与肿瘤生长张雪峰综述葛忠良审校北京放射医学研究所（北京市１００８５０）抑瘤素Ｍ（ＯｎｃｏｓｔａｔｉｎＭ，ＯＳＭ）最早于１９８６年被描述，作为一种生长调节分子，它能够抑制特定肿瘤细胞系的生长，刺激一些正常成纤维细胞系的生长［１］。后来的研究表明...     

抑瘤素M通过诱导衰老抑制肝癌细胞增殖

  目的  通过分析抑瘤素M（oncostatin M,OSM）对肝癌细胞生长的效应,研究其影响细胞增殖的分子机制。  方法  OSM处理SMMC-7721和HepG2肝癌细胞系,观察细胞的增殖速率和形态变化,结合特异性β-半乳糖苷酶染色和细胞周期分析,研究OSM是否通过诱导肝癌细胞进入衰老状态来抑制其增殖;进一步通过监测细胞周期抑制蛋白p16、p21、p27和癌基因c-Myc的表达变化,分析OSM诱导细胞衰老的原因。  结果  OSM可以抑制肝癌细胞系生长,且抑制率呈现一定剂量依赖性;细胞形态变化和β-半乳糖苷酶染色进一步证实OSM可诱导细胞衰老。细胞周期分析表明OSM阻滞肝癌细胞于G₀/G₁期,并伴随p21和p27周期抑制蛋白的表达增高。最后,通过分析STAT3信号途径下游癌基因c-Myc的转录与蛋白水平,表明OSM可能是通过癌基因的激活而诱导细胞的衰老。  结论  由癌基因激活而导致的细胞衰老,是机体的一种防御机制。OSM通过激活STAT3信号途径、上调癌基因cMyc表达的同时,也加速了细胞的衰老,从而最终表现为对肝癌细胞增殖的抑制作用。      

放射诱导抑瘤素M靶向肿瘤表达治疗肺癌实验研究

目的利用放射敏感性调控序列诱导抑瘤素M(OSM)靶向肺癌表达，探索肺癌治疗新方法。方法利用基因重组构建放射可调控的OSM表达载体pEO，转染肺腺癌A549细胞，观察γ线照射后细胞OSM表达及其对细胞相对存活分数和存活曲线的影响。利用肺癌移植瘤观察不同处理的抑瘤效应。结果γ线可诱导OSM在pEO转染肺癌细胞表达显著上调，呈剂量依赖性。pEO转染肺癌细胞株对辐射敏感性增强，增殖活性显著受抑。6Gy照射联合pEO转染可显著抑制移植瘤生长，并可使30％的移植瘤完全消退。结论由辐射敏感性启动子驱动的OSM肿瘤靶向性表达，可望为肺癌治疗提供一条新途径。     

多柔比星脂质体联合达卡巴嗪治疗不可手术切除硬纤维瘤的疗效初探

  目的  硬纤维瘤是一种交界性肿瘤,易复发,不转移。对于不可手术切除的硬纤维瘤患者可以考虑药物治疗。本研究探讨使用多柔比星脂质体联合达卡巴嗪方案治疗不可手术切除硬纤维瘤患者的临床效果。  方法  选取2015年1月至2019年12月北京大学肿瘤医院收治的35例不可手术切除的硬纤维瘤患者作为研究对象,其中男性11例,女性24例;发病年龄3～53岁,平均年龄27.5岁;肿瘤大小:T2（5～10 cm）6例,T3（10～15 cm）11例,T4（>15 cm）12例,6例多发,无T1（<5 cm）。所有患者均接受多柔比星脂质体联合达卡巴嗪方案化疗,每2个周期进行影像学评效,若有效,至少化疗6个周期,最长12个周期。  结果  化疗结束时评效,部分缓解（partial response,PR）10例,疾病稳定（stable disease,SD）24例,疾病进展（progressive disease,PD）1例,无完全缓解（complete response,CR）病例;客观反应率（objective response rate,ORR）为28.6%,疾病控制率（disease control rate,DCR）为97.1%。无进展生存时间（progression-free survival,PFS）2～50个月,中位无进展生存期（median progression- free survival,mPFS）为13个月,平均PFS为14.4 个月,23例完成计划化疗患者PFS超过12个月,在5例患者中观察到结束化疗后肿瘤仍持续缩小。  结论  对于不可手术切除的硬纤维瘤患者,多柔比星脂质体联合达卡巴嗪方案化疗是一种安全有效的药物治疗方法。      

B16黑色素瘤皮内移植瘤模型的建立

背景与目的： 建立B16黑色素瘤细胞(简称B16细胞)皮内移植瘤模型。 材料与方法： 制备商品源B16细胞悬液,按每只C57BL鼠接种0.1 ml (3×105个)B16细胞于后肢外侧皮内;分离、培养移植瘤源B16细胞,倒置显微镜下观察细胞形态。 结果： 移植瘤出现时间为(9.6±1.2)d,致瘤率为100％;皮内注射B16细胞18 d内,肿瘤形态呈圆形或类圆形,边缘清楚;移植瘤源原代B16细胞多为圆形、类圆形或短梭形,商品源B16细胞为梭形或不规则形;HE染色表明移植瘤内有大量B16细胞。 结论： B16细胞皮内移植瘤模型易于对肿瘤生长的观察和测量,是早、中期肿瘤研究的合适模型之一。     

黑色素瘤B16细胞热休克蛋白 抗原肽复合物的体内外抑瘤效应 *

黑色素瘤B16细胞胞浆HSP-抗原肽复合物（HAC）的制备、免疫原性的诱导及其抑瘤作用的研究。方法:采用Tris-HCl提取和Sephacryl S-200凝胶过滤制备B16细胞HAC,通过C57BL/6J小鼠体内诱导特异性CTL,再经体内、体外实验检测其抑瘤作用。结果:凝胶过滤获得的含60～97 kD蛋白的41,47和53管的HAC可以降低肿瘤发生率、延长肿瘤出现时间及降低小鼠死亡率。结论: B16 细胞胞浆中的60～97 kD的HAC具有免疫原性及抑瘤作用,为制备肿瘤疫苗提供了实验依据。     

RNAi silencing of the WT1 gene inhibits cell proliferation and induces apoptosis in the B16F10 murine melanoma cell line

The Wilms' tumor protein 1 (WT1) is essential for tumor cell proliferation and is highly expressed in various hematological and solid malignancies including human malignant melanoma. We investigated whether WT1 expression is essential for growth in the B16F10 murine melanoma cell line. Toward this end, we examined WT1 protein expression and WT1 isoforms (17AA+/17AA-, KTS+/KTS-) in this cell line. WT1 was silenced by two RNA interference constructs, designated WT1-1 and WT1-2. RNA interference-mediated reduction of WT1 protein expression significantly inhibited B16F10 cell viability. Loss of WT1 also increased caspase-3 and poly-ADP-ribose polymerase activation, as well as apoptotic body formation, chromatin condensation, and DNA fragmentation. Together, these findings implicate decreased WT1 protein levels in the induction of apoptosis. These results imply that WT1 plays a distinct role in B16F10 melanoma growth.     

Chemoimmunotherapy with dacarbazine and aranose combined with interferon-alpha in disseminated cutaneous melanoma

Aranoza and dacarbazine (DTIC) monotherapy and in combinations with aranoza and interferon-alpha (IPHN-alpha) as well as DTIC and IPHN-alpha was given to 175 patients (89 males and 86 females, aged 23-78) with disseminated skin melanoma. The effectiveness of aranoza and DTIC monotherapy was practically identical. Total response to DTIC used in combination with IPHN-alpha increased insignificantly: 25.6%--in combination vs. 19.5% DTIC alone (p > 0.05). IPHN-alpha was most effective when used with aranoza (total objective response--31.7% vs. aranoza alone--16%). The best results were reported in cases heretofore untreated with cytostatic drugs. Total response (complete or partial remission) was recorded in 63% vs. 4.5% (p < 0.05) of patients who had received chemotherapy. In cases of aranoza+ IPHN-alpha treatment, complete and partial remission was reported in metastasis of the skin, subcutaneous fat, peripheral, retroperitoneal and abdominal (mesenteric) lymph nodes and lungs. There was no relapse of metastasis of the liver, intestinal tract, bones, breast or ovary.     

Blue light inhibits the growth of B16 melanoma cells.

Although a number of studies have been carried out to examine the biological effects of radiation and ultraviolet radiation (UV), little is known concerning the effects of visible light. In the present study, exposure of B16 melanoma cells to blue light (wavelength 470 nm, irradiance 5.7 mW / cm(2)) from a light-emitting diode (LED) inhibited cell growth in proportion to the period of exposure, with no increase observed in the number of dead cells. The number of B16 melanoma colonies that formed after exposure to blue light for 20 min was only slightly less than that in non-exposed controls, but the colony size as assessed by the area covered by colonies and cell counts per colony were markedly decreased. The percentages of G0 / G1 and G2 / M phase cells were markedly increased, with a reduction in S phase cells as determined by flow cytometry after exposure to blue light. Furthermore, analysis of the incorporation of 5-bromo-2'-deoxyuridine (BrdU) into DNA also showed a reduction in the percentage of S phase cells after exposure. These results indicate that blue light exerts cytostatic effects, but not a cytocidal action, on B16 melanoma cells.     

Cadherin-16 inhibits thyroid carcinoma cell proliferation and invasion

Cadherin-16 (CDH16), a member of the cadherin family of adhesion molecules, serves an important role in the formation and maintenance of the thyroid follicular lumen. Decreased expression of CDH16 has been reported to be associated with tumor stage in papillary thyroid cancer (PTC); however, previous analyses have been limited and the biological role of CDH16 in different subtypes of TC is unknown. To investigate the role of CDH16 in the occurrence and development of TC, bioinformatic analysis of three TC subtypes (PTC, follicular cell-derived TC and anaplastic TC) was performed using an extended data set from the Gene Expression Omnibus database, with additional confirmation using data from The Cancer Genome Atlas, as well as biopsies from 35 patients with PTC and TC or follicular cell lines. According to the dataset analysis, CDH16 was downregulated in PTC and follicular cell-derived and anaplastic TC; the downregulation in PTC was independent of DNA copy number variation. Furthermore, low expression levels of CDH16 were significantly correlated with tumor size, lymph node metastasis status and disease stage in 35 patients with PTC. Gene Set Enrichment Analysis suggested that CDH16 participated in DNA replication and cell adhesion pathways. To evaluate CDH16 activity, CDH16 was overexpressed in TC-derived BCPAP cells. CDH16 overexpression inhibited cell proliferation, migration and invasion and induced apoptosis by downregulating proteins associated with DNA replication and cell adhesion. These results support the identification of CDH16 as a valuable target for TC prognosis and therapy and, to the best of our knowledge, represent the first direct demonstration of its mechanistic role in TC.     

Association between pterostilbene and quercetin inhibits metastatic activity of B16 melanoma

Inhibition of cancer growth by resveratrol (trans-3,5,4'-trihydroxystilbene; RESV), a phytoalexin present in many plant species, is limited by its low bioavailability. Pterostilbene (3,5-dimethoxy-4'-hydroxystilbene; PTER) and quercetin (3,3',4',5,6-pentahydroxyflavone; QUER), two structurally related and naturally occurring small polyphenols, show longer half-life in vivo. In vitro growth of highly malignant B16 melanoma F10 cells (B16M-F10) is inhibited (56%) by short-time exposure (60 min/day) to PTER (40 microm) and QUER (20 microm) (approximate mean values of plasma concentrations measured within the first hour after intravenous administration of 20 mg/kg each polyphenol). Intravenous administration of PTER and QUER (20 mg/kg per day) to mice inhibits (73%) metastatic growth of B16M-F10 cell in the liver, a common site for metastasis development. The anti-metastatic mechanism involves: 1) a PTER-induced inhibition of vascular adhesion molecule 1 expression in the hepatic sinusoidal endothelium, which consequently decreases B16M-F10 cell adhesion to the endothelium through very late activation antigen 4; and 2) a QUER- and PTER-induced inhibition of Bcl-2 expression in metastatic cells, which sensitizes them to vascular endothelium-induced cytotoxicity. Our findings demonstrate that the association of PTER and QUER inhibits metastatic melanoma growth and extends host survival.     

分泌性表达载体V-pLNCX-s-hri对小鼠B16黑色素瘤生长的抑制作用

背景与目的：已有研究表明从人胎盘中提取纯化的人核糖核酸酶抑制因子（human ribonuclease inhibitor,hRI）对小鼠某些实体肿瘤的生长具有明显的抑制作用。本研究的目的是构建分泌性表达载体V-pLNCX-s-hri,并观察其对小鼠B16黑色素瘤生长的抑制作用。方法：将合成的小鼠IgG信号肽碱基序列与hRI基因序列连接后,重组到逆转录病毒载体V-pLNCX上构建分泌性表达载体V-pLNCX-s-hri。将PA137细胞用于病毒包装,NIH3T3细胞用于测定病毒滴度。采用RT-PCR和Western blot法检测hRI基因的表达。构建小鼠荷B16黑色素瘤模型,注射V-pLNCX-s-hri,同时用生理盐水、V-pLNCX和V-pLNCX-hri作为对照,用肿瘤组织重和微血管密度来评价V-pLNCX-s-hri对小鼠B16黑素瘤生长的抑制作用。采用ELISA方法测定B16细胞培养上清和小鼠血清中RI含量。结果：V-pLNCX-s-hri对培养的B16细胞的感染效率为38．5％。在感染V-pLNCX-s-hri后的B16细胞中检测到RI mRNA和蛋白的表达。感染后的B16细胞的培养上清中hRI的含量为0．228μg／mL。V-pLNCX-s-hri组小鼠外周血中RI的含量为0．249μg／mL,明显高于生理盐水组、V-pLNCX组和V-pLNCX-hri组的0．035μg／mL、0．028μg／mL和0．169μg／mL（P值均〈0．01）。生理盐水组、V-pLNCX组和V-pLNCX-hri组小鼠的瘤组织重分别为（1．90±1．12）g、（1．77±0．21）g和（1．10±0．46）g,显微镜下每10个视野的微血管平均数分别为89±6、87±7和41±8;而V-pLNCXI-s-hri组的瘤组织重为（0．82±0．34）g,血管平均数为34±4。V-pLNCX-s-hri组与各对照组相比,其瘤组织重和血管数量的差异都有统计学意义（P值均〈0．01）。结论：构建的分泌性表达载体V-pLNCX-s-hri能对B16细胞进行有效的感染,且在感染的B16细胞中分泌性高表达。V-pLNCX-s-hri对小鼠B16黑色素瘤的生长有明显的抑制作用,且效果优于V-pLNCX-hri。     

Oncostatin M signaling in human glioma cell lines

We have recently found that oncostatin M (OSM) is overexpressed in most human brain tumors. The effects of OSM are unclear with conflicting reports of growth stimulatory or inhibitory effects in various cell types. The aim of this study was to investigate the effects of OSM in 5 glioma cell lines and 7 short-term cultures of human gliomas and in normal cultured human astrocytes. None of the cell lines and short-term cultured tumor cells expressed OSM in vitro. OSM signals through a gp130 containing receptor complex over the JAK/STAT pathway. Immunofluorescence and RT-PCR analysis showed that the tumor cells express gp130 and the other receptor components, LIFRbeta and OSMRbeta. OSM treatment induced phosphorylation of STAT3 and STAT1 indicating presence of a functional JAK/STAT pathway. No OSM effect on proliferation was observed. OSM gave no protective effects against tumor necrosis factor-related apoptosis inducing ligand (TRAIL)-induced cytotoxicity.     

反义STAT3对肿瘤细胞增殖抑制和诱导凋亡的作用

背景与目的：研究表明STAT3蛋白在多种肿瘤组织或细胞中高表达。STAT3蛋白可能参与了肿瘤的形成和发生。本文拟研究STAT3蛋白在鼠黑色素瘤细胞B16、人肝癌细胞SMMC-7721、人肝癌细胞HepG-2、人肺癌细胞A549、人宫颈癌HeLa细胞株中表达和活化情况,研究反义STAT3寡核苷酸对B16细胞的增殖抑制和促凋亡作用,为进一步反义药物设计及应用于辐射领域作前期研究。方法：利用Western blot检测所选几种肿瘤细胞的STAT3蛋白表达和磷酸化情况、反义干涉前后B16细胞中STAT3蛋白表达和磷酸化活化的变化情况,MTT法检测细胞增殖变化,利用Hoechst33258染色对细胞凋亡作形态学上的观察．用Annexin V／PI复染结合流式细胞仪检测细胞早期凋亡。结果：所研究的几种肿瘤细胞中均可检测到STAT3蛋白的高表达和磷酸化;反义STAT3转染后,B16细胞中STAT3蛋白的表达量及磷酸化水平均有下降;转染后48h,在0到200nmol／L范围内,反义核酸浓度越高。对B16细胞的增殖抑制效应越强,但是并不能够完全抑制肿瘤细胞的增殖（P〈0．01）。寡核苷酸浓度超过250nmol／L时．正义对照也表现出一定的增殖抑制作用（P〈0．05）;转染后不同时间内检测,结果表明转染后24h反义核酸即开始表现出一定的增殖抑制效应,48h起表现出明显的抑制效应;反义转染后,检测各组细胞早期凋亡率：对照组早期凋亡率为5．52％．反义400、800、2000nmol／L组早期凋亡率分别为8．22％、9．99％．16．97％,正义对照400、800、2000nmol／L组早期凋亡率分别为5．87％、5．36％、13．31％。统计分析表明反义寡核苷酸与B16细胞作用后能够促进细胞的早期凋亡（P〈0．01）,正义低浓度转染组（400、800nmol／L组）与对照组无明显差别（P〉0．05）,而对照组与正义2000nmol／L组相比,细胞的早期凋亡率也有统计学差异（P〈0．01）。结论：B16、SMMC-7721、HepG-2、A549、HeLa等恶性肿瘤细胞株中STAT3蛋白高表达并且可检测到磷酸化水平的增高;反义转染后B16细胞中STAT3蛋白的表达和磷酸化水平降低．细胞增殖受到明显抑制。细胞的凋亡增加．表明STAT3可能成为肿瘤治疗新的分子靶位。     

Effects of FeSO4 on B16 melanoma cells differentiation and proliferation

The effects exerted by FeSO4, in the presence or absence of vitamin C, on melanogenesis and proliferation in mouse B16 melanoma cells in culture were analysed either in serum-free (MEM-N2) or in serum-supplemented media. These cellular parameters can be either stimulated or on the contrary inhibited, depending on the metal concentration, the presence or the absence of vitamin C and serum, and on the type of culture (subconfluent or clonal). Vitamin C toxicity for B16 cells was decreased in the presence of FeSO4.     

Syngeneic monoclonal anti-melanoma antibody that inhibits experimental lung metastasis of B16 melanoma

An objective method to evaluate experimental lung metastasis of murine melanoma has been established by sandwich radioimmunoassay using monoclonal anti-melanoma antibody (M2590). The assay system quantitatively detected melanoma antigens metastasized in the lung. The data obtained by radioimmunoassay were consistent with those obtained by the usual colony-counting method. By the use of these detection systems for lung metastasis, we found that only one particular syngeneic monoclonal antibody (M562) recognizing a proteinaceous determinant on melanoma antigen significantly inhibited experimental lung metastasis of melanoma cells (1/7-1/10 of controls), whereas other syngeneic monoclonal antibodies with the same specificity and the same immunoglobulin class or control antibody did not. It is therefore strongly suggested that the molecule recognized by M562 antibody plays an important role in lung metastasis of melanoma cells.