777 intake together with diuretics is the cause of idiopathic oedema is misleading. Incidentally, a Lancet editorial’ suggested that the first description of this condition was in 1922,8 not 1954 as MacGregor et al. suggest, well before the introduction of modern diuretics. Medical Division,
University Department of Materia Medica, Stobhill General Hospital,
Glasgow G21 3UW
M. G. DUNNIGAN J. R. LAWRENCE
COPPER, SUPEROXIDE RADICAL, DIETHYLDITHIOCARBAMATE, AND BLEOMYCIN CYTOTOXICITY
SIR,—Bleomycin, an antineoplastic agent isolated from Streptomyces verticillus, is effective against lymphomas, testicular carcinomas, and squamous-cell carcinomas. It is thought to work by interacting with D.N.A. and inducing strand breaks. The ability of bleomycin to degrade D.N.A. is inhibited by low concentration of chelators and metal ions (including copper) and increased by the superoxide radical (O2-)1 and H20z.2 Enhancement of bleomycin damage to D.N.A. by these and other agents may be mediated by hydroxyl radicals.3 However, the role of 02- and metal ions in overall bleomycin cytotoxicity (as opposed to D.N.A. damage alone) has not been studied. Preece et awl. suggested that reduced serum-copper levels may be beneficial to bleomycin therapy: they proposed using penicillamine, a copper chelator, to lower the serum-copper which can otherwise rapidly bind to injected bleomycin and lower its efficacy. Their early experience with penicillamine was encouraging. We felt that another copper chelator, diethyldithiocarbamate (D.D.C.), might be more effective than penicillamine in bleomycin therapy. Cu++ from patients with Wilson’s disbe less toxic than penicillamine.5 (2) D.D.C. is a potent inhibitor of superoxide dismutase (S.O.D.)6-8 whereas penicillamine is not.9 S.O.D., a copper-containing enzyme, is present in all respiring cells, protecting them from excess O2- related toxicity.’° Thus D.D.c.-treated cells should have lower S.O.D. activity. Since normal metabolism produces 02-, inhibition of the S.O.D. would cause a build-up of O2- in the cells. The increase in O2- might in turn enhance the bleomycin effect.1 (3) Although D.D.C. is a potent copper chelator, it does not interact with Fe (II). Bleomycin and Fe (II) are more effective in degrading D.N.A. than is either species alone." Oberley and Buettner3 have shown that binding of Fe (II) to bleomycine generates hydroxyl radical and that the enhanced effect of bleomycin by O2- is due to its ability to reduce Fe (III) to Fe (II). Fe (III) is ineffective in producing hydroxyl radicals. (4) Tumour cells generally have reduced levels of S.O.D.12,13 thus they are more affected by D.D.C. than normal cells in terms of the net mcrease of O2- after D.D.C. In theory, a higher level of O2- in D.D.C.treated tumour cells may provide additional differential effects of bleomycm between normal and tumour cells.
(1)
D.D.C. can remove excess
ease and may
7 Lancet, 1972, i, 1374. 8
Jungmann, P.Klin. Wschr. 1922, 1,
1. Ishida, R., 2 Nagai, K.,
1546.
Takahashi, T. Biochem. Biophys. Res. Commun. 1975, 66, 1432. Suzaki, H., Tanaka, N., Umezawa, H. J. Antibiot., Tokyo, 1969,
22, 624. 3
Oberley, L W., Buettner, G. R. F.E.B.S. Lett. (in the press). 4. Preece, A. W., Light, P. A., Evans, P. A., Nunn, A. D. Lancet, 1977, i, 5.Sunderman,
953.
Jr., F. W., White, J. C., Sunderman, F. W. Am. J. Med 1963, 34, 875. 6 Heikkila, R. E., Cabbat, F. S., Cohen, G. J. biol. Chem. 1976, 251, 2182. 7 Frank, L., Wood, D. L., Roberts, R. J. Biochem. Pharmac. 1978, 27, 251. 8 Lin, P.-S., Kwock, L., Butterfield, C. E. Radiat.Res. (in the press). 9 Heikkila, R. E., Cohen, G. in Superoxide and Superoxide Dismutases (edited by A. M. Michelson, J. M. McCord, and I. Fridovich; p. 367. London, 1977. 10 Fridovich, I in Free Radicals in Biology (edited by W. A. Pryor), vol. i, p. 1. New York, 1976. 11 Halliwell, B.F.E.B.S. Lett 1978, 92, 321. 12 Bozzi, A., Manell, I., Finazzi-Agro, A., Strum, R., Wolf, A. M., Mondovi, B., Rotilio, G. T. Mol. Cell. Biochem. 1976, 10, 11. 13 Sahu, S. K., Oberley, L. W., Stevens, R. H., Riley, E. F. J. natn. Cancer Inst 1977, 58, 1125.
To test our hypothesis that bleomycin is more cytotoxic in D.D.c.-treated cells, we have been doing some in-vitro studies on Chinese hamster cells (V79). D.D.C. treatment (0-1 1 mmol/1, 30 min at 37°C) eliminated the characteristic resistant portion of the bleomycin survival curve. 14, 15 Since the D.D.c. bleomycin survival curve becomes exponential, the cytotoxicity of bleomycine becomes dose dependent. For example, there is greater than 20-fold net increase in cytotoxicity to 30 fLg/ml of bleomycin (60 min) if the cells are pretreated with 0.1mmol/l D.D.C. for 30 min at 37°C. We are now studying the relative roles of O2- and Cu++ in bleomycin cytotoxicity and the combination D.D.c./bleomycin in animal tumours. Since penicillamine/bleomycin therapy has already been attempted4 perhaps combination of D.D.C. and bleomycin in tumour therapy should also be considered. This work was Cancer Institute.
supported by grant
CA-12178 from the National
Department of Therapeutic Radiology,
P. S. LIN L. KWOCK N. T. GOODCHILD
Division of Radiation Biology, Tufts-New England Medical Center, Boston, Massachusetts 02111, U.S.A.
PLASMA PERFUSION IN TREATMENT OF COLD RASH AND SYSTEMIC LUPUS ERYTHEMATOSUS with plasma perfusion the treatment of acute hepatic failure we decided to try this method to remove immunoglobulins from patients with cold rash and systemic lupus erythe-
SIR,-Encouraged by our through charcoal columns in
success
(S.L.E.). 43-year-old man was admitted to hospital with weakness, fatiguability, a widespread rash, and severe pruritus. His skin was covered with a pink to bright-red rash with marginal haemorrhages. Polyarthritis affected hand, wrist, and elbow joints. Clinical examination revealed severe heart-failure. The liver was enlarged and painful when palpated, and the spleen was also enlarged. No S.L.E. cells were found in the blood. For the previous 20 years the patient had had the cold rash along matosus
A
with continuous multiple rash with severe pruritus which got worse with any cooling. Despite long-term corticosteroid therapy the patient was never free of the rash and pruritus. A hot bath provided some relief. After preliminary therapy 2000 ml of the patient’s plasma was perfused through the one 300 ml charcoal column included into plasma line of continuous blood-cell separator (Aminco). During perfusion no complications were observed. On the next day the condition of the patient dramatically improved : the rash on his upper and lower extremities and the pruritus had disappeared. For 2 weeks after the perfusion no new rash appeared, despite cooling challenges. After low-dose corticosteroid therapy stable remission of the cold rash was achieved and the patient was discharged. Patient B, a 25-year-old woman was admitted to hospital with cold rash combined with S.L.E. She had had this for 11 years. Massive corticosteroid therapy brought no stable clinical effect. After cooling tests a massive diffuse skin oedema and
pruritus appeared immediately. Laboratorv investigations revealed L.E. cells in blood. Antinuclear antibodies (D.N.A.) and cryoglobulins were found. After short-term pre-perfusion therapy 3000 ml of plasma was perfused through two 300 ml charcoal columns included into plasma line of ’Celltrifuge’. Perfusion was tolerated well. On the next day the condition dramatically improved. The rash and pruritus disappeared and a cooling test was negative. No 14.
L.E.
cells
were
found in
Barranco, S. C., Humphrey, R.
blood,
nor were
M. Cancer Res.
anti-D.N.A. anti-
1971, 31, 1218
15. Terasima, T., Takabe. Y., Katsumata, T., Watanable, M, Umezawa, H.
J. natn Cancer Iust 1972, 49, 1093. 1. Lopukhin, Y M., Molodenkov, M N., Shurkalin, B. K., Anesteziol. Reanimatol. 1977, no. 2 p. 57 (in Russian).
Evseyev,
N. G.
University Department of Materia Medica, Stobhill General Hospital,
Glasgow G21 3UW
M. G. DUNNIGAN J. R. LAWRENCE
COPPER, SUPEROXIDE RADICAL, DIETHYLDITHIOCARBAMATE, AND BLEOMYCIN CYTOTOXICITY
SIR,—Bleomycin, an antineoplastic agent isolated from Streptomyces verticillus, is effective against lymphomas, testicular carcinomas, and squamous-cell carcinomas. It is thought to work by interacting with D.N.A. and inducing strand breaks. The ability of bleomycin to degrade D.N.A. is inhibited by low concentration of chelators and metal ions (including copper) and increased by the superoxide radical (O2-)1 and H20z.2 Enhancement of bleomycin damage to D.N.A. by these and other agents may be mediated by hydroxyl radicals.3 However, the role of 02- and metal ions in overall bleomycin cytotoxicity (as opposed to D.N.A. damage alone) has not been studied. Preece et awl. suggested that reduced serum-copper levels may be beneficial to bleomycin therapy: they proposed using penicillamine, a copper chelator, to lower the serum-copper which can otherwise rapidly bind to injected bleomycin and lower its efficacy. Their early experience with penicillamine was encouraging. We felt that another copper chelator, diethyldithiocarbamate (D.D.C.), might be more effective than penicillamine in bleomycin therapy. Cu++ from patients with Wilson’s disbe less toxic than penicillamine.5 (2) D.D.C. is a potent inhibitor of superoxide dismutase (S.O.D.)6-8 whereas penicillamine is not.9 S.O.D., a copper-containing enzyme, is present in all respiring cells, protecting them from excess O2- related toxicity.’° Thus D.D.c.-treated cells should have lower S.O.D. activity. Since normal metabolism produces 02-, inhibition of the S.O.D. would cause a build-up of O2- in the cells. The increase in O2- might in turn enhance the bleomycin effect.1 (3) Although D.D.C. is a potent copper chelator, it does not interact with Fe (II). Bleomycin and Fe (II) are more effective in degrading D.N.A. than is either species alone." Oberley and Buettner3 have shown that binding of Fe (II) to bleomycine generates hydroxyl radical and that the enhanced effect of bleomycin by O2- is due to its ability to reduce Fe (III) to Fe (II). Fe (III) is ineffective in producing hydroxyl radicals. (4) Tumour cells generally have reduced levels of S.O.D.12,13 thus they are more affected by D.D.C. than normal cells in terms of the net mcrease of O2- after D.D.C. In theory, a higher level of O2- in D.D.C.treated tumour cells may provide additional differential effects of bleomycm between normal and tumour cells.
(1)
D.D.C. can remove excess
ease and may
7 Lancet, 1972, i, 1374. 8
Jungmann, P.Klin. Wschr. 1922, 1,
1. Ishida, R., 2 Nagai, K.,
1546.
Takahashi, T. Biochem. Biophys. Res. Commun. 1975, 66, 1432. Suzaki, H., Tanaka, N., Umezawa, H. J. Antibiot., Tokyo, 1969,
22, 624. 3
Oberley, L W., Buettner, G. R. F.E.B.S. Lett. (in the press). 4. Preece, A. W., Light, P. A., Evans, P. A., Nunn, A. D. Lancet, 1977, i, 5.Sunderman,
953.
Jr., F. W., White, J. C., Sunderman, F. W. Am. J. Med 1963, 34, 875. 6 Heikkila, R. E., Cabbat, F. S., Cohen, G. J. biol. Chem. 1976, 251, 2182. 7 Frank, L., Wood, D. L., Roberts, R. J. Biochem. Pharmac. 1978, 27, 251. 8 Lin, P.-S., Kwock, L., Butterfield, C. E. Radiat.Res. (in the press). 9 Heikkila, R. E., Cohen, G. in Superoxide and Superoxide Dismutases (edited by A. M. Michelson, J. M. McCord, and I. Fridovich; p. 367. London, 1977. 10 Fridovich, I in Free Radicals in Biology (edited by W. A. Pryor), vol. i, p. 1. New York, 1976. 11 Halliwell, B.F.E.B.S. Lett 1978, 92, 321. 12 Bozzi, A., Manell, I., Finazzi-Agro, A., Strum, R., Wolf, A. M., Mondovi, B., Rotilio, G. T. Mol. Cell. Biochem. 1976, 10, 11. 13 Sahu, S. K., Oberley, L. W., Stevens, R. H., Riley, E. F. J. natn. Cancer Inst 1977, 58, 1125.
To test our hypothesis that bleomycin is more cytotoxic in D.D.c.-treated cells, we have been doing some in-vitro studies on Chinese hamster cells (V79). D.D.C. treatment (0-1 1 mmol/1, 30 min at 37°C) eliminated the characteristic resistant portion of the bleomycin survival curve. 14, 15 Since the D.D.c. bleomycin survival curve becomes exponential, the cytotoxicity of bleomycine becomes dose dependent. For example, there is greater than 20-fold net increase in cytotoxicity to 30 fLg/ml of bleomycin (60 min) if the cells are pretreated with 0.1mmol/l D.D.C. for 30 min at 37°C. We are now studying the relative roles of O2- and Cu++ in bleomycin cytotoxicity and the combination D.D.c./bleomycin in animal tumours. Since penicillamine/bleomycin therapy has already been attempted4 perhaps combination of D.D.C. and bleomycin in tumour therapy should also be considered. This work was Cancer Institute.
supported by grant
CA-12178 from the National
Department of Therapeutic Radiology,
P. S. LIN L. KWOCK N. T. GOODCHILD
Division of Radiation Biology, Tufts-New England Medical Center, Boston, Massachusetts 02111, U.S.A.
PLASMA PERFUSION IN TREATMENT OF COLD RASH AND SYSTEMIC LUPUS ERYTHEMATOSUS with plasma perfusion the treatment of acute hepatic failure we decided to try this method to remove immunoglobulins from patients with cold rash and systemic lupus erythe-
SIR,-Encouraged by our through charcoal columns in
success
(S.L.E.). 43-year-old man was admitted to hospital with weakness, fatiguability, a widespread rash, and severe pruritus. His skin was covered with a pink to bright-red rash with marginal haemorrhages. Polyarthritis affected hand, wrist, and elbow joints. Clinical examination revealed severe heart-failure. The liver was enlarged and painful when palpated, and the spleen was also enlarged. No S.L.E. cells were found in the blood. For the previous 20 years the patient had had the cold rash along matosus
A
with continuous multiple rash with severe pruritus which got worse with any cooling. Despite long-term corticosteroid therapy the patient was never free of the rash and pruritus. A hot bath provided some relief. After preliminary therapy 2000 ml of the patient’s plasma was perfused through the one 300 ml charcoal column included into plasma line of continuous blood-cell separator (Aminco). During perfusion no complications were observed. On the next day the condition of the patient dramatically improved : the rash on his upper and lower extremities and the pruritus had disappeared. For 2 weeks after the perfusion no new rash appeared, despite cooling challenges. After low-dose corticosteroid therapy stable remission of the cold rash was achieved and the patient was discharged. Patient B, a 25-year-old woman was admitted to hospital with cold rash combined with S.L.E. She had had this for 11 years. Massive corticosteroid therapy brought no stable clinical effect. After cooling tests a massive diffuse skin oedema and
pruritus appeared immediately. Laboratorv investigations revealed L.E. cells in blood. Antinuclear antibodies (D.N.A.) and cryoglobulins were found. After short-term pre-perfusion therapy 3000 ml of plasma was perfused through two 300 ml charcoal columns included into plasma line of ’Celltrifuge’. Perfusion was tolerated well. On the next day the condition dramatically improved. The rash and pruritus disappeared and a cooling test was negative. No 14.
L.E.
cells
were
found in
Barranco, S. C., Humphrey, R.
blood,
nor were
M. Cancer Res.
anti-D.N.A. anti-
1971, 31, 1218
15. Terasima, T., Takabe. Y., Katsumata, T., Watanable, M, Umezawa, H.
J. natn Cancer Iust 1972, 49, 1093. 1. Lopukhin, Y M., Molodenkov, M N., Shurkalin, B. K., Anesteziol. Reanimatol. 1977, no. 2 p. 57 (in Russian).
Evseyev,
N. G.
