Distant metastasis facilitated by BCG: spread of tumour cells injected in the BCG-primed site.

Tumour metastasis in BCG-pretreated mice was studied using a methylcholanthrene-induced fibrosarcoma in C3H/He mice. When tumour cells were injected into the BCG-primed site, distant metastasis occurred in the lungs and the popliteal lymph node, through this tumour did not metastasize in normal mice. Such metastases were increased in proportion to the number of tumour cells injected into the BCG-primed site, and developed soon after tumour challenge. Concomitant immunity developed well in the mice bearing such metastases, but did not inhibit metastatic growth. Experiments using 125I-labelled SRBC or tumour cells revealed that such cells egressed rapidly from the BCG-primed site. When the tumour was inoculated into the contralateral foot to the BCG-primed site, the incidence and the number of metastases was reduced. Furthermore, BCG infection induced an increase of platelet count. I.v. injection of this tumour induced marked thrombocytopenia in normal mice. Administration of pentoxifylline, a methylxanthine derivative before tumour challenge reduced such metastases. These findings suggest that the changes in peripheral blood, such as increased platelet count and increased release of tumour cells from the injection site, facilitated distant metastasis in BCG-pretreated mice.     

Type-oriented therapy for gastric cancer effective for lymph node metastasis: management of lymph node metastasis using activated carbon particles adsorbing an anticancer agent.

Activated carbon particles are taken selectively up by lymphatics when injected into the tissues and visualize regional lymph nodes colored black. Furthermore, carbon particles adsorb a large amount of the anticancer agent mitomycin C (MMC) on their surface and release the drug reversibly. Using these properties of activated carbon particles, we have applied it for lymph node dissection and chemotherapy of lymph node metastasis. After injection of carbon particles, regional lymph nodes of the stomach were found to be black; blackened lymph nodes extending widely from perigastric to para-aortic nodes were identified from other structures. Four hundred and twenty-four patients with gastric cancer were treated with this method for lymph node metastasis during 1984-1988. Involved nodes were generally colored in high incidence, about 70% of involved ones except for highly positive nodes, which was the same as noninvolved nodes. In highly positive nodes, the colored incidence was decreased to about 48%. The cumulative 5-year survival rate of the patients treated with this series was 74.6%, which was significantly higher than the figures without this method.     

Study of the Dextran-DTPA-Gd at rabbit popliteal fossa lymph node metastasis from thigh transplanted tumor with interstitial magnetic resonance lymphography

Objective:The aim of the study was to investigate the developing situation of the interstitial magnetic resonance (MR) lymphoid contrast agent Dextran-DTPA-Gd through the rabbit popliteal fossa lymph node metastasis from thigh VX2 transplanted tumor injection to show targeting enhanced metastatic lymph nodes and lymphatics. Methods:VX2 tumor was transplanted to the right hind limb quadriceps of 12 healthy New Zealand rabbits and the left side as a contrast. Eight rabbits had homonymy popliteal lymph node metastasis after 1 month through 3.0 GE MRI and they were later injected with lym-phatic targeting contrast agent Dextran-DTPA-Gd 0.4 mL (3.96 × 10-3 mol/L) through bilateral hindlimb toe web respectively. Enhanced MR images were obtained with interval 10 min, 15 min, 20 min, 25 min, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, 60 min, 2 h, 4 h, and 24 h. The signal intensities before and after enhancing were measured to calculate the enhanc-ing rates (E%) of popliteal lymph node and the popliteal lymph node signal intensity-time curves were drawn to observe the development of cancer metastasis lymph nodes and lymphatics and to compare the dif erences of interval sides. Results:Ten minutes after injected into the rabbit’s bilateral hindlimb toe web, we could see hind lymphatic and popliteal lymph nodes were strengthened significantly and evenly without blood vessels developing. The signal reached a peak after 35 min with E%to 315%, which decreased to 205%after 4 h and would be undif erentiated with the surrounding tissues after 24 h. Sta-tistical analysis was made to popliteal lymph node enhancement rate. It was considered statistical y significant as long as P<0.05. The tumor-side popliteal lymph node manifested as coarse and irregular shape, lymphatic vessels tortuous dilated and lymphatic chain incomplete as a result of tumor infection. Conclusion:Dextran-DTPA-Gd is specific to lymphoid tissue development. It can targeting display regional lymphatic drainage concretion and the morphology of normal and cancer cells metastasis lymph nodes rapidly.     

Enhanced lymphatic delivery of mitomycin C conjugated with dextran

Absorption and lymphatic transfer of a polymeric prodrug of mitomycin C (MMC), mitomycin C-dextran conjugate (MMC-D), following i.m. injection were studied in rats in order to assess the feasibility of a macromolecular prodrug as a lymphotropic delivery system. Three types of MMC-D, conjugates with dextran with molecular weights of 10,000, 70,000 and 500,000, were synthesized, and the disposition of MMC was determined by bioassay. Following i.m. injection of MMC-D, MMC was retained at the injection site for a long period in a conjugated form while MMC administered as a free form disappeared rapidly. The disappearance was markedly influenced by the size of carrier dextran, because the remaining amount of MMC increased with an increase of molecular size. The lymphatic uptake of the drug was evaluated by determining the concentration in the regional lymph nodes and thoracic lymph fluid. In contrast to a slight lymphatic uptake following i.v. and i.m. injection of free MMC, MMC-D exhibited remarkable accumulation in the regional lymph nodes after i.m. injection which persisted up to 48 hr. MMC-D (Mr 10,000) appeared in the thoracic lymph as both the conjugated and the free form. Larger MMC-D gave a persistent supply of free MMC in thoracic lymph, suggesting that it was accumulated in the lymph node and supplying MMC continuously. These MMC-Ds suppressed the lymph node metastases introduced by a s.c. inoculation of L1210 leukemia cells. The usefulness of MMC-D as a lymphotropic delivery system for preventing lymphatic metastasis of cancer was suggested.     

Enhanced therapeutic efficacy on lymph node metastasis by the use of peplomycin adsorbed on small activated carbon particles

Mice into which 5 x 10(5) MH134 tumor cells had been inoculated subcutaneously opposite the foot-pad of the left hind paw on day 0, received subcutaneous injection of 0.25 mg/mouse of peplomycin in the form of PEP-CH (peplomycin adsorbed on activated carbon particles) or peplomycin aqueous solution into the foot-pad of the left hind paw on day 10. The left popliteal lymph nodes were transferred intraperitoneally to normal mice (the recipients) on day 14. In the PEP-CH group the survival time of the recipients was statistically significantly longer and the transferred tumor cell number estimated by calibration curve was markedly smaller in comparison with those in the other treatment groups.     

Cyclophosphamide-dependent Lymph Node Modification in Lymph Node Metastasis of MM48 Tumor Cells in Syngeneic Mice

We investigated the role of immunosuppressive activity induced in the regional lymph nodes (RLN, popliteal lymph nodes) in the establishment of lymph node metastasis by cyclophosphamide (CY) administration. The CY treatment led to the elimination of suppressive activity with the appearance of positive immune responses, and the inhibition of lymph node metastasis of MM48 tumor cells. In CY-treated mice, the removal of RLN together with the primary tumor lowered the survival rate compared with the mice in which the RLN remained intact. During 4 days after primary tumor resection, the proliferation of tumor cells in the RLN was significantly decreased in CY-treated mice. These results suggested that the induction of suppressive activity in the lymph node is closely associated with the establishment of lymph node metastasis.     

Cyclophosphamide-dependent lymph node modification in lymph node metastasis of MM48 tumor cells in syngeneic mice

We investigated the role of immunosuppressive activity induced in the regional lymph nodes (RLN, popliteal lymph nodes) in the establishment of lymph node metastasis by cyclophosphamide (CY) administration. The CY treatment led to the elimination of suppressive activity with the appearance of positive immune responses, and the inhibition of lymph node metastasis of MM48 tumor cells. In CY-treated mice, the removal of RLN together with the primary tumor lowered the survival rate compared with the mice in which the RLN remained intact. During 4 days after primary tumor resection, the proliferation of tumor cells in the RLN was significantly decreased in CY-treated mice. These results suggested that the induction of suppressive activity in the lymph node is closely associated with the establishment of lymph node metastasis.     

Chemotherapy Targeting Regional Lymph Nodes by Gastric Submucosal Injection of Liposomal Adriamycin in Patients with Gastric Carcinoma

We investigated the delivery of adriamycin (ADR) to the regional lymph nodes of the stomach following the gastric submucosal injection of liposomal adriamycin (Lipo-ADR) in 34 gastric carcinoma patients, as well as following intravenous administration of free ADR (F-ADR) in another 18 patients. Prior to radical gastrectomy, Lipo-ADR was endoscopically injected into the gastric submucosa adjacent to the primary tumor via a needle-tipped catheter. After Lipo-ADR injection, the ADR concentration in the primary and secondary drainage lymph nodes was higher than in the other regional lymph nodes. Thus, the regional nodes more susceptible to metastasis showed higher levels of ADR. In contrast, the intravenous administration of F-ADR produced a similar and far lower ADR concentration in all the nodes. Delivery of ADR to the primary drainage lymph nodes following injection of 5 ml of Lipo-ADR was compared with delivery to the left gastric artery lymph nodes after intravenous administration of an equal dose of F-ADR. The ADR levels (μg/g) after gastric submucosal injection were 15.1±8.30 on day 1 (n = 4); and 11.9±4.80 on day 4 (n = 6). Those after intravenous administration were 0.29±0.10 on day 1 (n = 4); and 0.36±0.0 on day 4 (n = 2). The differences between the two groups were significant (P<0.05). The ADR levels after the gastric submucosal injection were far higher than those after intravenous administration. These findings indicate that the gastric submucosal injection of Lipo-ADR can specifically deliver ADR to the regional lymph nodes at high concentrations. Such preoperative adjuvant chemotherapy targeting the regional lymph nodes may be useful for preventing the lymph node recurrence of gastric carcinoma.     

小鼠腘窝淋巴结模型评价3种中药注射液的潜在免疫毒性

目的：利用小鼠直接腘窝淋巴结（D-PLNA）和报告抗原腘窝淋巴结（RA-PLNA）对脉络宁、生脉、丹香冠心3种中药注射液的免疫毒性进行评价。方法：D-PLNA模型中设脉络宁、生脉、丹香冠心3种中药注射液,生理盐水对照组和阳性药物苯妥英钠对照组;RA-PLNA模型中上述各组分别加入报告抗原三硝基苯基聚蔗糖（TNP-Ficoll）和三硝基苯基卵蛋白（TNP-OVA）,每组8只BALB/c小鼠,于左足趾部给药50 μL。第7天处死小鼠分离腘窝淋巴结,研磨制备淋巴单细胞悬液并进行细胞计数,计算细胞指数;将细胞悬液培养于96孔板中,加入刺激剂共孵育后,利用酶联免疫吸附试验（ELISA）测定细胞上清液中免疫球蛋白IgE和单核细胞趋化蛋白-1（MCP-1）的含量。结果：与生理盐水对照组比较,小鼠D-PLNA模型中,仅丹香冠心注射液组腘窝淋巴结细胞数显著增加（P < 0.05）;小鼠RA-PLNA模型中,各给药组与TNP-Ficoll作用时,细胞数目和MCP-1浓度均显著升高（P < 0.05）,各给药组与TNP-OVA作用时,脉络宁注射液能显著刺激IgE分泌,同时丹香冠心注射液IgE和MCP-1含量均显著升高（P均 < 0.05）。结论：脉络宁和生脉注射液仅在加入报告抗原后引起小鼠淋巴结阳性反应,说明两者中可能存在作为半抗原的小分子物质诱发I型超敏反应,而丹香冠心注射液成分复杂,可能直接诱导Ⅰ型超敏反应,也可能存在新的抗原或表位诱发免疫反应。     

裸小鼠人大肠癌淋巴道转移模型的建立

 目的建立一种人大肠癌简便、可行、稳定的淋巴道转移研究动物模型。方法裸鼠爪垫皮下注射人结肠癌HCT-116细胞,接种后在1~6周及8周不同时间段取材;收集腹股沟、腘窝,髂血管旁,肾门淋巴结以及肝肺脏器;进行HE染色及CEA免疫组化检测。观察种植瘤的成瘤率、生长情况以及淋巴结转移规律。结果爪垫种植1周后成瘤率100%。3周后淋巴结开始转移,到6周时第一级腹股沟腘窝淋巴结完全转移,转移率100%,其中腹股沟淋巴结转移阳性率76.9%(10/13);第二级髂血管旁淋巴结部分转移,转移率40%(2/5);未见第三级肾门淋巴结转移。到8周时见髂血管旁淋巴结转移率60%(3/5),肾门淋巴结开始转移(1/5),但均未见肝肺远处转移。HE染色及CEA免疫组化染色发现淋巴结有弥漫性癌细胞浸润。结论裸鼠爪垫皮下注射可成功建立人大肠癌淋巴道转移模型。此模型快速简便、转移集中、转移率高,可为研究结直肠癌淋巴道转移机制,药物干预等抗转移治疗提供理想的动物模型。     

A new lymph node imaging agent--99mTc-polyphase liposome oleatis (99mTc-plo)

A new lymph node radio-imaging agent, technetium-99m polyphase liposome oleatis (99mTc-plo), has recently been developed. Polyphase liposome oleatis was labelled with radionuclide by stannous chloride method. The labelled rate was 90% or more as technically identified by thin layer chromatography, external gamma-camera imaging and radioautography. In animal experiment, 0.2-0.3 ml (0.2 mci) of the 99mTc-plo was injected subcutaneously into the toes web of rats. After half an hour, the regional lymph nodes of popliteal fossa were visualized very clearly. The imaging figures may keep their distinct shadow up to 24 hours. The tested rabbits were sacrificed 10 hours after 99mTc-plo injection for detecting various kinds of tissue and organ with a scintillation counter. The regional lymph nodes revealed the highest uptake rate of the new agent, 12,116; 1,303; 1,615 times higher than that of the adjacent muscles, liver and spleen, respectively. In clinical experiment, 0.2-0.3 ml (0.5-0.8 mci) of the 99mTc-plo was injected subcutaneously into the toes web of patients. Half an hour later, the lymph nodes of inguinal, external iliac and common iliac regions appeared in sequence. If the new agent is injected perianally, the internal iliac lymph nodes will be seen. No side effect was observed in both types of experiment. This new agent has been tried in rats, rabbits and dogs with similar positive results. The new lymph node imaging technique is simple, safe, reliable and reproducible. This agent, being directed toward the lymph nodes and possessing affinity to cancer cells, is expected to be supplementary method to CT and B-ultrasonography for detecting lymphoid malignancy and lymph node metastasis.     

纳米炭混悬注射液示踪前哨淋巴结对宫颈癌淋巴结清扫及病理结果的影响

目的 探究纳米碳混悬注射液在宫颈癌手术治疗中对前哨淋巴结的示踪以及对淋巴结清扫及病理结果的影响.方法 选取宫颈癌患者58例,随机分为示踪组和对照组.示踪组进行纳米碳混悬溶液注射,两组患者均行宫颈癌根治术(广泛子宫全切除术+双侧盆腔淋巴及清除术).比较两组患者的淋巴结清扫情况和病理组织学检查结果.结果 术中肉眼观察示踪组患者的盆腔淋巴结均有黑染,示踪成功率为100%;对前哨淋巴结(包括髂内和闭孔淋巴结)的示踪成功率为93.10%;纳米碳混悬溶液对前哨淋巴结的黑染率比对其他部位(髂外和髂总)淋巴结的黑染率高(P＜0.05).两组患者手术时长、术中出血量以及淋巴结清扫数比较无显著差别(P＞0.05).术后病理结果显示:示踪组4例有淋巴结转移,均为前哨淋巴结,其中3例有黑染;对照组2例患者淋巴结转移,均为前哨淋巴结.结论 纳米碳混悬溶液能有效示踪宫颈癌前哨淋巴结,是1种安全高效的淋巴结示踪剂.     

活体染料注射法识别乳腺癌患者前哨淋巴结失败及假阴性原因分析

目的 探讨活体染料注射法识别乳腺癌患者前哨淋巴结失败及假阴性的原因。方法 84例早期乳腺癌患者采用活体染料亚甲蓝作为前哨淋巴结活检示踪剂。术中切除前哨淋巴结行常规冰冻切片检查,无肿瘤转移者进一步做免疫组化检测。术后分离出全部乳腺及腋窝淋巴结送病理检查。结果 11例患者术中未检出前哨淋巴结,失败率13.1%。73例检出前哨淋巴结的患者中,32例前哨淋巴结受肿瘤累及,病理证实这些患者均有腋窝淋巴结转移;2例患者前哨淋巴结未受肿瘤累及,但病理证实腋窝淋巴结转移,前哨淋巴结预测腋窝淋巴结状态的敏感性为90.4%,特异性1005,假阴性率2.7%。结论 活体染料注射法识别前哨淋巴结失败主要与外科医师的技术熟练程度及方法欠妥有关,而假阴性的出现多为原发肿瘤过大及前哨淋巴结位置变异所致。     

Metachronous seeding of lymph node metastases in rats bearing the MT-100-TC mammary carcinoma: The effect of elective lymph node dissection

Summary Following the introduction of cancer cells into the lymphatic system, metastases in down-stream lymph nodes often appear in a sequential manner. This could be due to synchronous seeding of the in-line nodes with progressively diminishing numbers of tumorigenic cancer cells, or alternatively, by discrete, stepwise (metachronous) seeding of down-stream nodes by up-stream nodal metastases acting as generalizing sites. Metachronous seeding to local lymph nodes is potentially curable by elective lymph node dissection; synchronous seeding is not.Synchronous versus metachronous seeding of lymph node metastases was investigated using the MT-100-TC mammary carcinoma injected into the hind foot-webs of rats. When the primary tumor was removed by amputation one week after injection, 1/15 animals survived; in contrast, removal of the draining popliteal lymph node in addition to the primary lesion, resulted in 8/19 long-term survivors. At this time, occult metastases detectable by bioassay butnot by conventional histology, were present in all draining popliteal nodes and in 60 percent of lungs. The fact that some amputees were cured when the popliteal node was removed, indicated the metachronous nature of nodal metastases in this system. Further, recurrence of nodal and lung metastases in those amputees in which the popliteal node was left intact, identified the popliteal node as a generalizing site. By the time popliteal node involvement was evident by conventional histology, micrometastases were present in down-stream nodes, and accordingly, removal of the popliteal node and the primary lesion at this time was not curative.     

Growth of a transplantable lymphoma and its modification in mice infected with the inducing virus.

The growth of a transplantable lymphoma was examined in normal mice and in mice previously infected with the lymphoma-inducing virus (ULV). Normal BALB/c mice respond to a footpad injection of X-irradiated lymphoma cells (ULMC) with popliteal lymph node (PLN) enlargement; mice previously infected with ULV do not. 106 viable ULMC injected into the footpads of ULV-infected mice grew progressively, and the animals died with disseminating malignant lymphoma. In contrast, this dose of cells injected into normal animals evoked strong host responses in the foot and draining lymph node, and no progressive growth of the lymphoma occurred. This increased susceptibility of the ULV-infected animals was also observed when ULMC were injected s.c. into the back or i.m. into the calf muscle, but not after s.c. injection of an unrelated 3-methylcholanthrene-induced sarcoma. Resistance to tumour growth after i.v. injection of ULMC is clearly ineffective, since 10 cells can grow and kill the animal, and in this case no increased susceptibility of ULV-infected animals was observed.     

Orthotopic treatment model of prostate cancer and metastasis in the immunocompetent mouse: efficacy of flt3 ligand immunotherapy

We established an orthotopic treatment model of prostate cancer to generate reproducible primary and metastatic carcinoma in immunocompetent C57BL/6 mice. Using an in vivo selection scheme of intraprostatic implantation of TRAMP-C1 cells, primary prostate tumors were cultured and recycled three times by intraprostatic injection resulting in the selection and establishment of the recycled cell line TRAMP-C1P3. Prostate tumors were detected approximately 30 days post-implantation with periaortic lymph node metastasis in 19/20 (95%) of mice. Tissue culture amplification, DNA ploidy and PCR amplification of the SV40 transgene were used to detect metastatic TRAMP-C1P3 in lymph node specimens. Tissue culture amplification and DNA ploidy were as sensitive as SV40 transgene amplification by PCR in detection of early metastatic disease in draining lymph nodes. To establish the use of the orthotopic model of prostate cancer for immunotherapy, mice were injected orthotopically with TRAMP-C1P3 cells and 7 days post-implantation treated daily for 28 days with either flt3L or carrier control. Carrier-treated mice had clinically detectable prostate tumors, lymph node metastasis and were moribund at 29-35 days, whereas flt3L therapy markedly suppressed primary TRAMP-C1P3 growth and lymph node metastasis, and prolonged survival. In summary, we have established a reproducible and clinically relevant orthotopic treatment model of prostate cancer in immunocompetent mice with application to a variety of therapeutic strategies. We demonstrate that flt3L treatment suppressed orthotopic prostate tumor growth and lymph node metastasis reinforcing a role for flt3L as an immunotherapeutic strategy for prostate cancer.     

The prognostic advantage of preoperative intratumoral injection of OK-432 for gastric cancer patients

To investigate, by a multi-institutional randomized trial, the prognostic significance of the augmentation of tumour-infiltrating lymphocytes (TILs) by preoperative intratumoral injection of OK-432 (OK-432 it), a bacterial biological response modifier, in patients with gastric cancer. The 10-year survival and disease-free survival were examined and analysis of the factors showing survival benefit was performed. 370 patients who had undergone curative resection of gastric cancer were enrolled in this study and followed up for 10 years postoperatively. Patients were randomized into either an OK-432 it group or a control group. Ten Klinishe Einheit (KE) of OK-432 was endoscopically injected at 1 to 2 weeks before the operation in the OK-432 it group. Both groups received the same adjuvant chemoimmunotherapy consisting of a bolus injection of mitomycin C (0.4 mg kg(-1) i.v.) and administration of tegafur and OK-432 from postoperative day 14 up to 1 year later. Tegafur (600 mg day(-1)) was given orally and OK-432 (5 KE/2 weeks) was injected intradermally for a maintenance therapy. The TILs grades in resected tumour specimens and presence of metastasis and metastatic pattern in dissected lymph nodes were examined. Multivariate analysis was performed to determine the efficacy of OK-432 it on prognostic factors. All patients were followed up for 10 years. The overall 5- and 10-year survival rates and disease-free survival rates of the OK-432 it group were not significantly higher than those of the control group. However, OK-432 it significantly increased the 5- and 10-year survival rates of patients with stage IIIA + IIIB, moderate lymph node metastasis (pN2), and positive TILs. OK-432 it was most effective at prolonging the survival of patients who had both positive TILs and lymph node metastasis. The OK-432 it group with positive TILs showed a significant decrease in metastatic lymph node frequency and in the number of lymph node micro- metastatic foci when compared to the control group. This study showed that only one time preoperative OK-432 it, particularly when it triggers TILs, is effective for reduction of regional lymph node metastasis. OK-432 it probably acts partly by eliminating micro-metastatic foci in lymph nodes. Preoperative intratumoral injection of OK-432 is technically very easy and has no serious adverse effects, so it is a promising form of neoadjuvant immunotherapy for advanced gastric cancer.     

乳腺癌前哨淋巴结活检术新型示踪剂的动物模型研究

背景与目的：前哨淋巴结活检已成为临床腋淋巴结阴性早期乳腺癌患者的标准处理模式,并对疾病的分期和治疗方案的选择至关重要。该研究将吲哚菁绿和利妥昔单抗进行偶联作为新型示踪剂,采用小鼠后肢引流作为动物模型,模拟乳腺癌前哨淋巴结活检术,探索其定位效应。方法：小鼠后肢脚背皮下注射不同剂量的示踪剂,应用荧光脉管系统成像仪连续观测腘窝淋巴结(作为前哨淋巴结)至3 h,探索最佳注射剂量和显像时间。注射最佳剂量的示踪剂,观察至24 h,探索其持续定位效应。结果：随着注射剂量的增加,前哨淋巴结开始显像与达到最佳显像的时间均逐渐缩短,次级及第3级淋巴结显像率逐渐升高。新型示踪剂的最佳注射剂量为0.12μg(吲哚菁绿的含量),达最佳显像时间约为34 min。观察至24 h,前哨淋巴结显像率维持在100%,次级及第3级淋巴结显像率由6 h的0%和0%上升至20%和10%。结论：吲哚菁绿-利妥昔单抗能清晰定位前哨淋巴结且6 h内无次级淋巴结显像,具有较高的临床应用价值。     

Inhibition of lymph node metastasis by an anti-angiogenic agent, TNP-470.

We assessed the inhibitory action of TNP-470 on lymph node metastasis in a metastatic model system using athymic nude mice. Mice were injected subcutaneously with 5 x 10(6) HT-1080 cells in the right groin. TNP-470 (10, 30 and 100 mg kg-1) was injected subcutaneously nine times in total every other day from the 7th day after tumour inoculation. Axillar and inguinal lymph nodes were dissected, and DNA was extracted 5 weeks after tumour inoculation. Specific detection of a human beta-globin-related sequence in metastasized human tumour cells in nude mice was done by the polymerase chain reaction (PCR) technique and analysed by Southern blotting. Anti-tumour effects on primary sites were seen only in the 100 mg kg-1 treatment group. Lymph node metastasis of transplanted HT-1080 cells was seen in all mice of the no treatment group (5/5). On the other hand, incidences of lymph node metastasis in treated mice were 2/4 mice (100 mg kg-1, 2/5 mice (30 mg kg-1) and 4/5 mice (10 mg kg-1). The inhibition ratios of lymph node metastasis were 82.3% at 10 mg kg-1, 97.2% at 30 mg kg-1 and 97.5% at 100 mg kg-1 respectively. This agent may be useful to inhibit lymph node metastasis.