荷EL4肿瘤小鼠模型的建立及美法仑抑瘤作用免疫机制的探讨

目的:建立荷小鼠淋巴瘤EL4的野生型C57BL/6小鼠及其裸鼠模型,探讨美法仑(melphalan)抑瘤作用的免疫机制。方法:给正常野生型C57BL/6小鼠皮下接种小鼠淋巴瘤EL4细胞,建立荷EL4肿瘤的小鼠模型。于野生型C57BL/6小鼠皮下接种瘤细胞后12d,经腹腔给荷瘤小鼠单次注射不同剂量的美法仑,找出美法仑可发挥最大的抑瘤作用,并能致使肿瘤消退、不再复发的最小使用剂量。然后再给野生型C57BL/6小鼠及其裸鼠(遗传背景相同)皮下同时接种小鼠淋巴瘤EL4细胞建立两种荷瘤小鼠模型。同样于接种瘤细胞后12d,经腹腔给两种荷瘤小鼠模型均注射可使野生型C57BL/6小鼠肿瘤消退、不再复发的最低剂量的美法仑,以正常野生型C57BL/6小鼠为对照,观察在T淋巴细胞缺陷的裸鼠体内美法仑的抑瘤作用。结果:注射7.5mg/kg美法仑治疗后,免疫功能正常的野生型C57BL/6荷瘤小鼠的肿瘤消退;而荷瘤C57BL/6裸鼠的肿瘤仍继续生长。结论:单一剂量的美法仑对荷淋巴瘤EL4小鼠具有明显的治疗作用,其作用的发挥需要T淋巴细胞的参与,可能与T细胞的杀伤作用有关。     

美法仑治愈荷瘤小鼠的过程与TNFα的关系

目的探讨单一剂量的美法仑治愈荷瘤野生型C57BL/6小鼠的过程与肿瘤坏死因子α(TNFα)的关系。方法以3种遗传背景相同、肿瘤坏死因子受体1(TNFR1)基因型不同的TNFR1 / 、TNFR1 /-和TNFR1-/-C57BL/6小鼠为实验动物,皮下接种数量相同的小鼠淋巴瘤EL4细胞。接种瘤细胞后12d,给基因型不同的各组荷瘤小鼠腹腔内单次注射7.5mg/kg的美法仑。以荷瘤野生型C57BL/6小鼠(TNFR1 / )为对照,观察美法仑对荷瘤TNFR1 /-C57BL/6小鼠和荷瘤TNFR1-/-C57BL/6小鼠的治疗效应。结果在美法仑(7.5mg/kg)治疗后的1周内,基因型不同的各组荷瘤小鼠肿瘤消退的速度基本相同。在随后的2月内,荷瘤TNFR1 / 和TNFR1 /-C57BL/6小鼠的肿瘤结节逐渐消退、肿瘤治愈;而多数荷瘤TNFR1-/-C57BL/6小鼠的肿瘤结节缩小后又再次出现并逐渐长大、肿瘤复发。结论TNFα与美法仑治愈肿瘤的过程密切相关,其中美法仑的抗肿瘤作用与荷瘤小鼠TNFR1的表达无关,但在美法仑治疗后,机体预防或避免肿瘤复发方面需要TNFR1在机体细胞的表达,而不是在肿瘤细胞的表达。     

Single-agent high-dose melphalan salvage therapy for Hodgkin's disease: Cost, safety, and long-term efficacy

Background: Few data are available on the cost, safety, and long-termefficacy of single agent high-dose melphalan (HDM) followed by autologousbone marrow (ABMT) or blood stem cell (ABSCT) transplantation in the salvagetherapy of Hodgkins disease (HD).Patients and methods: From February 1981 to September 1996, 23 patientswith relapsed (n = 15) or refractory (n = 8) HD received salvage therapywith HDM 140–200 mg/m² followed by non-cryopreservedABMT (n = 18) or cryopreserved ABSCT (n = 5). The cost of HDM/ABSCT in 1996,from initial consultation until transfer back to referring physician, wasdetermined and compared to the estimated costs of two multi-agent regimenscommonly used for HD.Results: HDM was well tolerated with no early transplant-relatedmortality. The five-year overall and progression-free survival rates were52% and 50%, respectively. The average total cost in Canadianfunds of HDM/ABSCT in 1996 was $34,400/patient. This cost wasestimated to be $4,700–6,800 cheaper per patient than themulti-agent high-dose regimens.Conclusion: These data suggest that HDM is safe, feasible, active, andreasonably inexpensive salvage therapy for patients with relapsed/refractoryHD.     

31P and 1H MRS of DB‐1 melanoma xenografts: lonidamine selectively decreases tumor intracellular pH and energy status and sensitizes tumors to melphalan

In vivo ³¹P MRS demonstrates that human melanoma xenografts in immunosuppressed mice treated with lonidamine (LND, 100 mg/kg intraperitoneally) exhibit a decrease in intracellular pH (pH_i) from 6.90 ± 0.05 to 6.33 ± 0.10 (p < 0.001), a slight decrease in extracellular pH (pH_e) from 7.00 ± 0.04 to 6.80 ± 0.07 (p > 0.05) and a monotonic decline in bioenergetics (nucleoside triphosphate/inorganic phosphate) of 66.8 ± 5.7% (p < 0.001) relative to the baseline level. Both bioenergetics and pH_i decreases were sustained for at least 3 h following LND treatment. Liver exhibited a transient intracellular acidification by 0.2 ± 0.1 pH units (p > 0.05) at 20 min post‐LND, with no significant change in pH_e and a small transient decrease in bioenergetics (32.9 ± 10.6%, p > 0.05) at 40 min post‐LND. No changes in pH_i or adenosine triphosphate/inorganic phosphate were detected in the brain (pH_i, bioenergetics; p > 0.1) or skeletal muscle (pH_i, pH_e, bioenergetics; p > 0.1) for at least 120 min post‐LND. Steady‐state tumor lactate monitored by ¹H MRS with a selective multiquantum pulse sequence with Hadamard localization increased approximately three‐fold (p = 0.009). Treatment with LND increased the systemic melanoma response to melphalan (LPAM; 7.5 mg/kg intravenously), producing a growth delay of 19.9 ± 2.0 days (tumor doubling time, 6.15 ± 0.31 days; log₁₀ cell kill, 0.975 ± 0.110; cell kill, 89.4 ± 2.2%) compared with LND alone of 1.1 ± 0.1 days and LPAM alone of 4.0 ± 0.0 days. The study demonstrates that the effects of LND on tumor pH_i and bioenergetics may sensitize melanoma to pH‐dependent therapeutics, such as chemotherapy with alkylating agents or hyperthermia. Copyright © 2012 John Wiley & Sons, Ltd.     

Proteasome inhibition in hematologic malignancies

Hematologic malignancies, including multiple myeloma (MM), will account for more than 100,000 new cases of cancer and over 57,000 deaths in the United States in 2003. Treatment of MM is a serious challenge, because despite a variety of available therapies, median survival is short. A new therapeutic area focuses on inhibiting the activity of the proteasome, a 26S protease complex involved in cell cycle regulation, cell adhesion, inflammation, and protein turnover. The novel proteasome inhibitor, bortezomib (Velcade®), was recently approved for use in patients with refractory and relapsed MM and to date is the only proteasome inhibitor to have entered clinical trials. Bortezomib has demonstrated activity with manageable toxicity in a variety of hematologic malignancies in addition to MM, including leukemia and non‐Hodgkin's lymphoma. This article reviews clinical information on bortezomib in hematologic malignancies both as monotherapy and in combination with dexamethasone. Preliminary reports of bortezomib in combination with Doxil (pegylated liposomal doxorubicin), melphalan, and thalidomide are discussed, and current trials are described. Available data suggest that bortezomib will be useful in the treatment of a variety of hematologic malignancies.     

A pilot study of 220 mg/m2 melphalan followed by autologous stem cell transplantation in patients with advanced haematological malignancies: pharmacokinetics and toxicity

We studied the pharmacokinetics and toxicity of 220 mg/m² melphalan (HDM 220) followed by autologous stem cell transplantation in 16 patients with advanced haematological malignancies. Pharmacokinetic parameters (mean values of steady-state volume of distribution 14.6 l/m², total body clearance 313 ml/min/m², elimination half-life 46 min) were the same as those of 140 or 200 mg/m² melphalan in previous reports. HDM 220 was feasible. Extramedullary toxicity was mainly W.H.O. grade 4 mucositis (13/16 patients). The median duration of 41 d (10, not reached) of thrombocytopenia <25 × 10⁹/l was long. In multiple myeloma the response rate was 89% in heavily pretreated patients, suggesting that HDM 220 could be considered earlier in the course of the disease as an alternative consolidation therapy.     

Refractory Crow-Fukase Syndrome (POEMS Syndrome) Successfully Treated with High-Dose Melphalan followed by Autologous Peripheral Blood Stem Cell Transplantation

Crow-Fukase syndrome (CFS) is a multisystemic disorder. Because it is characterized by polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, sclerotic bone lesions, and skin changes it is also known as POEMS syndrome. Extravascular volume overload is also one of the main symptoms. Uncontrollable extravascular volume overload is one of the major causes of death and one of the negative prognostic factors. Control of the extravascular volume overload is an important therapeutic strategy for this syndrome. We report here a case of CFS with extravascular volume overload resulting in pleural effusion and massive edema in the lower extremities, which was refractory to oral administration of melphalan and prednisolone. The patient's condition correlated with the serum level of vascular endothelial growth factor and markedly improved after administration of high-dose melphalan (200 mg/m²) followed by autologous peripheral blood stem cell transplantation. This approach should be considered in patients with CFS who fail to respond to conventional chemotherapy and have uncontrollable extravascular volume overload.     

Busulfan and melphalan as conditioning regimen for autologous peripheral blood stem cell transplantation in multiple myeloma

Summary. Twenty-four patients with multiple myeloma (MM), three (12-5%) in complete remission (CR) and 21 (87-5%) in partial remission (PR) were treated with high-dose chemotherapy (HDCT) (busulfan 12 mg/kg-l-melphalan 140mg/m²) as preparative regimen for autologous peripheral blood stem cell (PBSC) transplantation. These cells were previously collected by leukapheresis after mobilization by high-dose cyclophosphamide (HD Cy) + rhGM-CSF (18 patients) or rhG-CSF alone (six patients). Considering 23 evaluable patients following HDCT, the CR rate was 58% (14 patients) and the PR rate was 38% (nine patients). One transplant-related death occurred following this regimen (4%). With a median follow-up of 20 months (range 4-34) after transplantation, 21 patients are alive (87%). Disease progression after transplantation was observed in four patients. Overall and relapse-free actuarial survival at 24 months was 91% and 74%, respectively. 12 patients (50%) remain in CR 15 months (4-34) post transplant. The major toxicity was mucositis. Busulfan + melphalan is a safe and feasible conditioning regimen for APBSCT in MM with acceptable toxicity and a high objective response rate, which may result in prolonged survival.