Antitumor activities of KW-2152, a new isoquinon agent,against human tumor xenografts transplanted into nude mice

The antitumor activities of KW-2152, a new isoquinon derivative, were examined in thirteen human tumor xenografts, transplanted into nude mice. KW-2152 was administered intravenously at a schedule of q4d×3, in daily doses of 7.3 mg/kg and 3.6 mg/kg, and q2d×6 with a daily dosis of 7.3 mg/kg, respectively. KW-2152 displayed significant antitumor activities against the human tumor xenografts in 3 out of 13 strains (23.1 per cent) at the schedule of q4d×3, with a daily dose of 7.3 mg/kg. Depending on the schedule of administration, tumor activity was observed in 8 out of 13 strains (61.5 per cent) at a schedule of q2d×6, with a daily dose of 7.3 mg/kg. SH-2 and SH-9 gastric tumors were sensitive to KW-2152 and growth was completely inhibited with the schedule of q4d×3, and a daily dose of 7.3 mg/kg. Thus, KW-2152 seems to have a wide antitumor spectrum, and the possible antitumor effects for clinical use, warrant attention.     

Antitumor effects of recombinant human tumor necrosis factor against human tumor xenografts transplanted into nude mice

Antitumor activities of recombinant human tumor necrosis factor (rH-TNF) against human tumor xenografts in nude mice were studied. Thirteen human tumor xenografts serially transplanted into nude mice were used for experiments; five gastric, two breast, two gallbladder, one colon and one esophageal carcinoma, one liposarcoma and one squamous carcinoma of the neck. They were inoculated into the subcutaneous tissue of BALB/c nu/nu nude mice and the treatment was started when the estimated tumor weight reached 100–300 mg. rH-TNF was administered intratumorally at schedule of qd×5 or q3d×5. rH-TNF showed a marked antitumor activity against various human tumors. The hemorrhagic necrosis was observed in all types of the human tumor xenografts (100 per cent), and the complete regression of the tumor was noted in 4 of 11 tumors (36.4 per cent). On the contray, intraperitoneal rH-TNF exhibited little antitumor effect. The additive effect in the combination of TNF and Mitomycin C was observed against two Mitomycin C resistant gastric tumors.     

Antitumor effects of recombinant human tumor necrosis factor against human tumor xenografts transplanted into nude mice

Antitumor activities of recombinant human tumor necrosis factor (rH-TNF) against human tumor xenografts in nude mice were studied. Thirteen human tumor xenografts serially transplanted into nude mice were used for experiments; five gastric, two breast, two gallbladder, one colon and one esophageal carcinoma, one liposarcoma and one squamous carcinoma of the neck. They were inoculated into the subcutaneous tissue of BALB/c nu/nu nude mice and the treatment was started when the estimated tumor weight reached 100-300 mg. rH-TNF was administered intratumorally at schedule of qd X 5 or q3d X 5. rH-TNF showed a marked antitumor activity against various human tumors. The hemorrhagic necrosis was observed in all types of the human tumor xenografts (100 per cent), and the complete regression of the tumor was noted in 4 of 11 tumors (36.4 per cent). On the contrary, intraperitoneal rH-TNF exhibited little antitumor effect. The additive effect in the combination of TNF and Mitomycin C was observed against two Mitomycin C resistant gastric tumors.     

Experimental studies on the combined effects of alpha and gamma interferons against human tumor xenografts transplanted into nude mice

The antitumor activities, resulting from the combined treatment of leukocyte interferon (IFN-alpha), with recombinant human immune interferon (IFN-gamma), against human tumor xenografts in nude mice, were studied. Nine human tumor xenografts, (7 from gastric carcinoma, 1 from gallbladder carcinoma and 1 from breast carcinoma), were serially transplanted into nude mice for the purpose of this experiment. Each human tumor xenograft was inoculated subcutaneously into BALB/c nu/nu nude mice and treatment was started after the estimated tumor had reached 100-300 mg. IFN was administered intramuscularly at a schedule of qd X 14. Treatment with either IFN-alpha or IFN-gamma alone, did not produce any antitumor effect against the various human tumor xenografts, however the combination of IFN-alpha with IFN-gamma resulted in achieving significant antitumor effects against the various human tumors. Inhibition of tumor growth was observed in 7 of the 9 tumors (77.8 per cent), and regression of the tumor was noted in 5 of the 9 tumors (55.6 per cent).     

Experimental studies on the combined effects of alpha and gamma interferons against human tumor xenografts transplanted into nude mice

The antitumor activities, resulting from the combined treatment of leukocyte interferon (IFN-α), with recombinant human immune interferon (IFN-γ), against human tumor xenografts in nude mice, were studied. Nine human tumor xenografts, (7 from gastric carcinoma, 1 from gallbladder carcinoma and 1 from breast carcinoma), were serially transplanted into nude mice for the purpose of this experiment. Each human tumor xenograft was inoculated subcutaneously into BALB/c nu/nu nude mice and treatment was started after the estimated tumor had reached 100–300 mg. IFN was administered intramuscularly at a schedule of qd×14. Treatment with either IFN-α or IFN-γ alone, did not produce any antitumor effect against the various human tumor xenografts, however the combination of IFN-α with IFN-γ resulted in achieving significant antitumor effects against the various human tumors. Inhibition of tumor growth was observed in 7 of the 9 tumors (77.8 per cent), and regression of the tumor was noted in 5 of the 9 tumors (55.6 per cent).     

Differential antiproliferative activities of alpha- and gamma-interferon and tumor necrosis factor alone or in combinations against two prostate cancer xenografts transplanted in nude mice

We have investigated the antiproliferative effects of recombinant human alpha- and gamma-Interferon (IFN) and recombinant human Tumor Necrosis Factor alpha (TNF) against the hormone-independently growing PC3 and DU145 prostatic tumor lines. Subcutaneous, peritumoral administration of the drugs was started 24 hours after subcutaneous implantation of 1–2 mm³ tumor pieces. IFN was given three times per week and TNF five times per week. IFN-alpha (dose-range 0.5–5 ng/gram bodyweight) had significant growth-inhibiting effects against the PC3 tumor, but showed no significant antitumor effects against the DU145 tumor. IFN-gamma monotherapy (dose-range 8–80 ng/gram bodyweight) was less effective than IFN-alpha. 500 ng/gram TNF produced growth inhibition of both tumors, whereas the lower dose (50 ng/g) was only effective against the PC3 tumor. IFN-alpha and -gamma combination treatment had significant antiproliferative effects against the PC3 tumor, but not against the DU145 tumor. Combinations of IFN-alpha and TNF were very effective against both xenografts; some combinations resulted in complete growth inhibition. IFN-gamma and TNF combinations also showed significant antitumor effects against both tumor lines. We therefore conclude that cytokine combination treatment may provide a new approach in the treatment of hormone-escaped prostatic tumors.     

Screening model of anticancer drugs against human cancer transplanted into the subrenal capsule of nude mice

Xenografts of human tumors in nude mice have more advantages to evaluate drug response than conventional experimental models. However, this method has difficulties in establishing tumor growth and in evaluating drug response in short period. In order to evaluate drug response in short time and to apply it on clinical study, we examined a newly devised method of sensitivity test in which tumor tissues were inoculated subrenal capsules of nude mice. The drug doses were decided from LD50 values of nude mice. Drug effects were estimated ten to twelve days after tumor implantation. Subrenal capsule implants grew early without latent period in nude mice, but in BDF1 normal mice those were diminished and disappeared within four to seven days after inoculation. The results of drug response in this method almost agreed with the method of subcutaneous inoculation in which drug effects were estimated three weeks after tumor inoculation.     

Histologic differentiation of human fetal pancreatic explants transplanted into nude mice

The transplantation of human fetal pancreas has been suggested as a means of treatment of insulin-dependent diabetes in man. We have obtained human fetal pancreata during the second trimester of pregnancy and transplanted 1-mm3 explants subcutaneously (s.c.) into both diabetic and nondiabetic nude mice, some of the tissue being cultured in vitro before implantation. These implants coalesced and grew. They were removed at intervals up to 37 wk later and showed selective differentiation of endocrine tissue that normally occurs in the fetus and neonate, with formation of bipolar, mantle, and mature islets. There was growth of this endocrine tissue with significantly more islets than in the freshly stained fetal pancreas assuming an average dimension larger than 150 micron, which is the reported mean diameter of a neonatal islet. Duct and fibrous tissue remained viable, but there was no definitive acinar tissue seen. The pancreata uncultured before implantation reached a larger size than that attained by those implants cultured before being transplanted, the difference probably being the amount of ductular and mesenchymal tissue still present. Of those glands cultured before transplantation, the longer the period of culture, the smaller the size the implants reached. Culture beyond 3 wk in vitro made it difficult to macroscopically locate the implant. These data show that, in human fetal pancreas removed from its usual environment, both selective differentiation of the endocrine component and growth of the islets can occur.     

alphastatin抑制胃癌细胞裸鼠移植瘤血管生成的实验研究

目的探讨alphastatin对裸鼠体内新生血管形成和人胃癌细胞裸鼠移植瘤血管生成的抑制作用及机制。方法裸鼠皮下注射基质胶溶液形成基质胶体。测定alphastatin对基质胶体内新生血管的抑制作用。人胃癌BGC823细胞接种于裸鼠皮下形成移植瘤。分别于裸鼠腹腔注射磷酸盐缓冲液（PBS）和不同剂量的alphastatin（100nmol／L,0．25mg·kg^-1·d^-1;1000nmol／L,2．5mg·kg^-1·d^-1）,测定各组瘤体大小、体质量并进行病理学分析,测定微血管密度（MVD）计数。分离瘤体内血管内皮细胞．经alphastatin处理后,提取细胞内蛋白,进行细胞鞘氨醇激酶（SPK）活性测定。结果裸鼠移植瘤实验中．与PBS对照组相比,两个不同剂量alphastatin实验组裸鼠移植瘤的体积和体质量均得到了不同程度的抑制[体积：（1145．96±29．89）μm^3、（612．65±23．45）μm^3比（1771±31．05）μm^3,P〈0．05;瘤体质量：（0．31±0．03）g、（0．12±0．02）g比（0．67±0．02）g,P〈0．05]。体外实验病理学证实．alphastatin减少了瘤体内MVD的数目．降低了移植瘤体内血管内皮细胞SPK活性．上述作用均呈现一定的量-效关系。结论alphastatin具有明显抑制人胃癌细胞裸鼠移植瘤血管生成的作用．这种效应与降低血管内皮细胞SPK活性、减少1-磷酸鞘氨醇（SIP）的生成有密切关系。     

Anticancer drug screening test for human osteosarcoma transplanted into nude mice

Osteosarcoma tissue was transplanted into the subcutis of nude mice, and an anticancer drug was injected into the abdomen of the mice. The effects of Cis-platinum, SF-1739HP, Melphalan, Peleomycin and Aclacinomycin were tested. Only Cis-platinum had previously been used in the treatment of osteosarcoma. As the conventional method of evaluation, tumor weight change was recorded along the time course. As a new evaluation method, toluidine-blue was added into the tumor cell suspension prepared from the tumor tissue in the back of nude mice. By the intensity of staining, the tumor cells in suspension were classified into 3 categories; strongly-positive, weakly-positive and negative. Results of evaluation by the staining method were similar to those by measurement of tumor weight. Cis-platinum proved to be most effective, followed in decreasing order by SF-1739HP, Melphalan, Pepleomycin and Aclacinomycin. In conclusion, the staining method is simple and useful for screening the anti-cancer effects of drugs.     

Sensitivity of anticancer agents on human gastric cancers transplanted into nude mice

In the chemotherapy for gastric cancer, the most sensitive anticancer agent against individual tumors should be prescribed. The establishment of a sensitivity test using nude mice as anin vivo model is urgently awaited by clinicians and researchers alike. Seventy-three tumors derived from human gastric cancer were transplanted subcutaneously into nude mice and these mice were then treated intraperitoneally with anticancer agents. Mitomycin C (MMC), 5-fluorouracil (5-FU) and cyclophosphamide (CPM) were used. The doses given were 3 mg/kg of MMC, 75 mg/kg of 5-FU and 200 mg/kg of CPM. In 52 of the 73 cancers, chemosensitivity was evaluated by the microscopic changes in the tumors. The rate of positive sensitivity against gastric cancer was 44.2% in MMC, 34.6% in 5-FU and 30.8% in CPM, respectively. The sensitivity of each agent tested by this method indicated a good correlation with the clinical therapeutic effects. Our results suggest the feasibility of evaluation of the sensitivity of various agents from the microscopic changes on tumors transplanted into nude mice.     

Heterogeneity of xenografted osteosarcoma: A human sarcoma transplanted into nude mice

Human osteoblastic osteosarcoma transplanted into nude mice developed two different subtypes of nonosteogenic sarcoma: one solid and the other cystic. This could reflect the heterogeneity of osteoblastic osteosarcoma; various tumor regions have different characteristics.     

Heterogeneity of xenografted osteosarcoma: A human sarcoma transplanted into nude mice

Human osteoblastic osteosarcoma transplanted into nude mice developed two different subtypes of nonosteogenic sarcoma: one solid and the other cystic. This could reflect the heterogeneity of osteoblastic osteosarcoma; various tumor regions have different characteristics.     

Heterogeneity of xenografted osteosarcoma. A human sarcoma transplanted into nude mice.

Human osteoblastic osteosarcoma transplanted into nude mice developed two different subtypes of non-osteogenic sarcoma: one solid and the other cystic. This could reflect the heterogeneity of osteoblastic osteosarcoma; various tumor regions have different characteristics.     

The effects of estrogen on human breast carcinomas serially transplanted into nude mice

The effect and mechanisms of 17 beta-estradiol (E2) on breast cancer cells were studied in vivo and in vitro, using 5 human breast carcinomas serially transplanted into nude mice. These carcinoma strains consisted of 4 estrogen receptor (ER) positive tumors and 1 ER negative tumor. Mice bearing these tumors were treated with an intramuscular injection of E2 at a dosage of 50 mg/kg and the tumor doubling time (Td) was calculated in days. The tumor growth was significantly stimulated by E2 in 3 out of the 4 ER positive tumors, the Td of the E2 treated groups being 17.6 days for MCF-7 (control: -17.8 days), 12.8 days for R-27 (control: -12.5 days approximately 14.5 days) and 10.4 days for Br-10 (control: 14.5 days), however, in the T-61 tumor, the growth was inhibited by E2 in a dose dependent manner. In the case of the ER-negative MX-1 tumor, the tumor cell growth was not affected by E2. Discrepancies between the effects of E2 on ER-positive tumors were further analyzed by examining the steroid hormone receptor status and conducting in vitro growth studies. In vitro clonogenic cell assay reproduced the antitumor activity of E2, indicating that E2 directly inhibits part of the cell growth of T-61 tumors. The above results suggest that this experimental system provides a useful tool for analyzing the mechanism of estrogen in breast cancer and that the clonogenic assay using ER positive specimens can help to identify breast cancers sensitive to estrogen therapy.     

The effects of estrogen on human breast carcinomas serially transplanted into nude mice

The effect and mechanisms of 17β-estradiol (E₂) on breast cancer cells were studiedin vivo andin vitro, using 5 human breast carcinomas serially transplanted into nude mice. These carcinoma strains consisted of 4 estrogen receptor (ER) positive tumors and 1 ER negative tumor. Mice bearing these tumors were treated with an intramuscular injection of E₂ at a dosage of 50 mg/kg and the tumor doubling time (Td) was calculated in days. The tumor growth was significantly stimulated by E₂ in 3 out of the 4 ER positive tumors, the Td of the E₂ treated groups being 17.6 days for MCF-7 (control: −17.8 days), 12.8 days for R-27 (control: −12.5 days∼14.5 days) and 10.4 days for Br-10 (control: 14.5 days), however, in the T-61 tumor, the growth was inhibited by E₂ in a dose dependent manner. In the case of the ER-negative MX-1 tumor, the tumor cell growth was not affected by E₂. Discrepancies between the effects of E₂ on ER-positive tumors were further analyzed by examining the steroid hormone receptor status and conductingin vitro growth studies.In vitro clonogenic cell assay reproduced the antitumor activity of E₂, indicating that E₂ directly inhibits part of the cell growth of T-61 tumors. The above results suggest that this experimental system provides a useful tool for analyzing the mechanism of estrogen in breast cancer and that the clonogenic assay using ER positive specimens can help to identify breast cancers sensitive to estrogen therapy.     

Prostatic adenocarcinoma PC EW, a new human tumor line transplantable in nude mice

A serially transplantable human prostatic carcinoma line, PC EW, has been developed through heterotransplantation of tumor tissue from a lymph node metastasis. PC EW is androgen dependent and is similar to the original tumor in terms of histological pattern, amounts of prostatic acid phosphatase secreted, and absence of a hormonally independent subline. This line is thus similar to PC 82, and we herein report the first results of comparative treatment trials conducted on PC EW.