Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025202 (melanoma)
 69,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The formation and removal of nitrogen mustard (HN2)- and melphalan-induced DNA cross-links (DNA interstrand and DNA-protein cross-links) in a human melanoma cell line (RPMI 8322), as determined by alkaline elution of DNA, was compared and related to the cytotoxic effect of each drug. HN2 was considerably more cytotoxic than melphalan as determined by inhibition of colony formation. Immediately following exposure to HN2 maximum levels of DNA cross-links were found. Melphalan, in contrast, caused a protracted induction of DNA cross-links with maximum levels obtained 6-12 h following drug exposure. HN2 induced approximately 13 times higher peak levels of DNA cross-links compared to equal concentrations of melphalan. Removal of DNA cross-links following exposure to both drugs followed an exponential time course. The rate of removal of HN2-induced DNA cross-links was, however, 1.5-2.4 times more rapid than that of melphalan-induced cross-links. A strong correlation was obtained between the cytotoxicity of both drugs and the total area under the curve for DNA interstrand cross-links, indicating that both the initial induction of as well as the rate of removal of DNA interstrand cross-links are important for the cytotoxic effects of bifunctional alkylating agents.
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PMID:Formation and removal of DNA cross-links induced by melphalan and nitrogen mustard in relation to drug-induced cytotoxicity in human melanoma cells. 356 96

This is the case report of a 37-year-old female who underwent primary excision of a malignant melanoma on the left foot as well as an inguinal lymphnode dissection in May 1983. In January 1984 a satellitosis on the same foot was treated with an isolation perfusion which had to be repeated in December of the same year due to secondary satellitosis. For the first perfusion, Alkeran 80 mg was used with a temperature of up to 41.4 degrees C, whereas Cis-Platinum 20 mg/l and Eldesine 0.3 mg/l were used for the second perfusion, with a maximum temperature in the tumor area of 39.0 degrees C. On the first postoperative day, significant edema of the left leg accompanied by severe pain was noticed. This was followed by an increase of the serum creatinine to 2.2 mg % two days later. Despite the immediate inducement of a forced diuresis, renal function deteriorated during the following days with serum creatinine going up to 4.8 % and CK to 14800 U/L. After a forced diuresis of two weeks' duration, the laboratory parameters slowly went back to normal. As a consequence of this complication we analyzed the influence of hyperthermic isolation perfusion on five patients with regard to muscular damage and its influence on renal failure. During perfusion we observed myoglobinemia which subsided within 36 hours. This slope was paralleled by CK values. A discrete myoglobinuria which was observed in two patients disappeared within 36 hours after perfusion. No rise of creatinine could be found. The changes described above were not influenced by cytostatic medication (Alkeran versus Cis-Platinum and Eldesine). In addition, none of the cases showed a leakage of over 16%. The case of acute renal failure was apparently caused by increased rhabdomyolysis as a consequence of the second hyperthermic perfusion.
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PMID:Acute renal failure following hyperthermic isolation perfusion of the left leg. 363 5

Verapamil had previously been shown to increase cellular melphalan uptake and cytotoxicity in fibrosarcomas, and increased the area under the blood concentration versus time curve (AUC) for melphalan in CBA mice. Verapamil (10 mg kg-1 i.p.) had no effect on the fractional distribution of cardiac output (FDCO), measured with 86Rb-rubidium chloride, to subcutaneous fibrosarcomas. 14C-Melphalan uptake by FS13 fibrosarcomas was increased 60 min after verapamil (10 mg kg-1 i.p.), but not after lower doses which did not affect the AUC. Flunarizine (5 mg kg-1 i.p.) also had no effect on FDCO to FS13 fibrosarcomas, and tended to increase 14C-melphalan content of blood and the fibrosarcomas and to promote growth delay by melphalan. Alcohol increased FDCO to FS13 fibrosarcomas, maximally at a 1:20 dilution in saline, but had no effect on 14C-melphalan uptake or growth delay. Thus, melphalan cytotoxicity correlated with tumour melphalan uptake, and both followed changes in the AUC for melphalan but not changes in FDCO. In these murine fibrosarcomas melphalan uptake and cytotoxicity were not limited by blood flow. In subcutaneous human melanoma HX46 xenografts, verapamil had no effect on the FDCO, nor on 14C-melphalan uptake, and did not affect blood 14C-melphalan levels, suggesting absence of effects on the AUC and on cellular uptake. Alcohol did not increase the FDCO to HX46 xenografts, providing evidence for a different vascular supply.
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PMID:Effects of verapamil and alcohol on blood flow, melphalan uptake and cytotoxicity, in murine fibrosarcomas and human melanoma xenografts. 371 18

To evaluate the utility of nude mouse xenografts as preclinical drug screens, the activity of ten established chemotherapeutic agents was evaluated against seven melanoma and three ovarian carcinoma xenografts. Xenografts were established using primary explants from patients who had not received chemotherapy and serially passaged as sc tumors in nude mice. In vivo drug activities for dactinomycin, carmustine, vinblastine, melphalan, amsacrine, cisplatin, bleomycin, mitomycin, doxorubicin, and etoposide were evaluated by 4 weekly ip injections of 10% less than LD10 doses. Plots of relative tumor growth versus time were nearly log-linear. Analysis of in vivo activity was performed using percent control growth (treated/control tumor volume) and by calculation of a novel growth delay index obtained by fitting growth curves to a quadratic regression model. Both modes of data analysis identified alkylating agents (melphalan, carmustine, and mitomycin) as the most active drugs against human melanomas. Melphalan, mitomycin, and cisplatin showed the greatest activity against ovarian xenografts. However, complete tumor regressions were noted only with melphalan, mitomycin, and cisplatin against a single ovarian tumor xenograft. Correlation analysis suggested xenograft tumor growth rate was an important determinant of drug response. These results suggest that preclinical, new-drug screening with melanoma xenografts would identify drugs such as alkylating agents as active, and may not provide an advantage over murine leukemia screens. However, screening with ovarian xenografts may more closely reflect clinical drug activity. Criteria for detecting active drugs in such systems are discussed.
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PMID:Use of nude mouse xenografts as preclinical drug screens: in vivo activity of established chemotherapeutic agents against melanoma and ovarian carcinoma xenografts. 381 95

The pharmacokinetics of isolated limb perfusion were studied to see what melphalan concentrations were achieved and how effective the isolation was. Twenty-eight patients received 32 limb perfusions with heat and melphalan for locally recurrent or level V melanoma. Melphalan was given 0.75 mg/kg for axillary/popliteal or 1.2 mg/kg for femoral perfusions with heat (perfusate 42 degrees C, limb 40 degrees C) for 1 hour. Melphalan concentratives were measured by high-performance liquid chromatography in seven patients. Peak perfusate melphalan concentrations were 6.1 to 115 mg/ml, which was one to two logs higher than peak systemic concentratives of melphalan. Isolation of the perfusate circuit from the systemic circulation was better for axillary and popliteal perfusions than for femoral perfusions (P less than 0.05). Complete responses were seen in 81% of evaluable patients; long-term local control was achieved in most patients, although many developed hematogenous metastases. Toxicity included erythema and edema in all, mild leukopenia in two, neuropathy in two, and amputation was required in one patient. Improvements in surgical technique include regional anesthesia to reduce vasospasms and transcutaneous measurement of fluorescein to measure leak. Perfusion with heat and melphalan remains the treatment of choice for in-transit metastases from melanoma.
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PMID:A clinical and pharmacokinetic study of isolated limb perfusion with heat and melphalan for melanoma. 399 75

The cytotoxic effect of melphalan, measured as drug induced inhibition of cellular 3H-thymidine incorporation, was lower in RPMI 8322 melanoma cells than in phytohaemagglutinin-stimulated lymphocytes. Melphalan induced a 1.8-fold higher level of total cross-linking and a 1.5-fold higher level of DNA interstrand cross-linking in the phytohaemagglutinin-stimulated lymphocytes compared to the RPMI 8322 melanoma cells. In addition, higher levels of cross-linking were found in the newly synthesized DNA of lymphocytes in S-phase, as compared to S-phase RPMI 8322 cells. The cellular incorporation of 3H-melphalan was about four times higher in RPMI 8322 cells than in phytohaemagglutinin-stimulated lymphocytes. Thus, the lower toxicity of melphalan in RPMI 8322 cells and the lower levels of melphalan induced DNA cross-linking in these cells is due to intracellular factors rather than a lower cellular uptake of melphalan.
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PMID:Different melphalan toxicity and DNA cross-linking in human melanoma cells as compared to phytohaemagglutinin-stimulated lymphocytes. 406 51

Melphalan resistance developed previously in a human melanoma cell line (MM253) could not be further increased. Cross-resistance was found to nitrogen mustard but not to ultraviolet light radiation. A clone of MM253 had the same drug sensitivity and heterogeneous chromosome complements as did the parent culture. The melphalan-resistant cells (MM253-12M) had 2.6-fold the D0, 1.5-fold the size, 1.3-fold the RNA content, 1.4-fold the protein content, and 2.6-fold the DNA content of the sensitive parent line. There was no evidence for activation or detoxification of melphalan by intact melanoma cells or by mouse liver microsomes competent for the activation of other drugs. Melphalan transport was similar in both cell lines, reaching a steady-state level 3 times the concentration in the medium after 2.5 min. Both lines covalently bound the same total amount of [3H]melphalan per cell, but in MM253-12M a 50% decrease in binding to DNA was almost sufficient to account for the increase in resistance. The level of melphalan-induced DNA interstrand cross-links, which were heat labile but not alkali labile, reached a maximum during the 4-hr treatment period and then declined slowly. The degree of cross-linking in MM253-12M was 50% less than that in MM253. Unlike ultraviolet light, methyl methanesulfonate, and nitrogen mustard, melphalan at equitoxic doses did not damage the DNA sufficiently to immediately inhibit DNA synthesis. Although both lines were proficient for repair of ultraviolet light and methyl methane sulfonate damage, melphalan did not induce significant levels of DNA repair synthesis and had little effect on the rate of DNA chain elongation. In MM253 cells, strand breaks were detected only at high melphalan doses; MM253-12M formed breaks more readily. This evidence suggests that the cross-linking events and that developed resistance arises from decreased susceptibility to DNA to this damage.
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PMID:Mechanism of melphalan resistance developed in vitro in human melanoma cells. 616 26

The optimal single dosage of melphalan in isolation perfusion of the limbs for malignant melanoma was assessed. For this purpose a method to determine the volume of the isolated region in the individual patient and a grading system for the reaction of the normal tissues were introduced. A strictly standardized pharmacosurgical routine was developed that permitted an analysis of the correlation between dosage and the grade of toxic reaction in 90 perfusions. The optimal dosage of a cytostatic drug was considered to be the highest amount tolerated at an acceptable risk. Melphalan at 10 mg/l perfused tissue was determined as the likely optimum. This dose provoked remarkably little variation in toxicity, all reactions falling within a safe range. No exception to the applicability of this dosage was encountered.
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PMID:Dosimetry in isolation perfusion of the limbs by assessment of perfused tissue volume and grading of toxic tissue reactions. 689 40

The in vivo response of B16 melanoma and Lewis lung carcinoma to combinations of hyperthermia and graded doses of CCNU or Melphalan was studied. To obtain dose-response curves and quantitative comparisons of different treatments, an agar-colony assay was used to measure survival of cells from excised tumours. For heating experiments, the use of 2 tumours per animal, one heated and one not, allowed all other factors to be kept constant. When tumours were immersed in a water-bath at 43 degrees C for 1 h, Thermal Enhancement Ratios (TER) measured from the slopes of the dose-response curves were up to 1.6 for CCNU and 2.4 for Melphalan. Direct heat killing of about 1 decade was seen for 1 h at 43 degrees C. The anaesthetic Saffan also enhanced drug cell kill; the largest Dose Modifying Factor (2.7) was measured for Melphalan in the Lewis lung tumour. The duration of heating, and waterbath temperature, both influenced the enhancement of cell killing by CCNU, as did the time of excision of tumours between 0 and 3 1/2 h after treatment. There was no difference in effect between 3 1/2 and 24 h. The interaction between heat and CCNU varied if the interval between them was altered. The maximum effect was found if the heat and drug were given in close sequence.
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PMID:Response of two mouse tumours to hyperthermia with CCNU or melphalan. 705 61

An in vitro chemosensitivity test has been applied to malignant melanoma cells from 5 patients. The tumour cells were first grown as xenografts in immune-suppressed mice, so that the results of the in vitro test could be compared with precise measurements of the sensitivity of the melanoma cells when exposed to chemotherapeutic drugs in vivo in the mouse. The in vitro assay involved exposing the tumour cells to each of 8 drugs, after which cell survival was determined by colony assay in soft agar. Dose-response curves were obtained and the surviving fraction at drug levels estimated to be achieved in man was used as a measure of in vitro drug sensitivity. Significant differences among the 8 drugs were detected, and these accorded with clinical experience. The correlation of in vivo (in the mouse) and in vitro sensitivities to Melphalan and MeCCNU was also significant.
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PMID:In vitro chemosensitivity tests on xenografted human melanomas. 737 Jan 59


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