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Ethidium bromide safety
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onitor genic mice were mammary adenocarcinomas, followed by malignant lymphomas, salivary gland adenocarcinomas, Harderian gland hyperplasias and seminal vesicle neoplasms. It was found in these studies that the simultaneous expression of the myc and ras oncogenes enhanced tumor formation and reduced latency, but still did not seem to be sufficient for transformation in vivo. T h e onset of expression and tumor formation still diverge, the tumors are clonal and the expressing cell populations are not homogeneously transformed, suggesting that additional genetic events need to be postulated. The presence of consistent chromosomal translocations, amplifications of chromosomal segments or loss of specific loci might help in finding the genes involved in cooperative functions. Questions about the mechanism of cooperativity, e.g. the distinction between a synergistic
Ethidium bromide safety The recent brief report in T I G 1 of the study by Lurm and Sansone 2 of ethidium bromide destruction fails to point out one very disturbing aspect of their findings, namely that the products of ethidium bromide destruction by the widely used method of treatment with hypochlorite bleach are more mutagenic
and a sequential model of oncogene action, might become approachable through conditional oncogene expression using hormonally regulated, tissue specific transgene constructs. Conclusions The use of targeted myc and ras expression has yielded additional insights into the intricacies of the transformation process, but no general rules about the effects of these two oncogenes can be formulated. Since it is not practicable to test the effect of every oncogene in every tissue, future experiments might have to focus on the expression of oncogenes consistently found to be involved in a high percentage of naturally occurring tumors of a certain type (e.g. myc in lymphomas TM, c-erbB-2 in mammary carcinomas13). Transgenic mouse tumors induced by these oncogenes might provide valuable model systems for experimental treatments based on
(in the test used) than ethidium bromide itself. As safety adviser in this department, I am concerned to find an acceptable procedure for ethidium bromide decontamination of transilluminators, etc. However I consider that the alternative method of treatment with hypophosphorous acid/sodium nitrite, which is recommended by Luun and Sansone and which they observed to give complete conversion of ethidium bromide to non-mutagenic products, is not
Pool your useful hints through Technical Tips Technical Tips is a place where readers can exchange information about new experimental techniques. To make this section really useful to experimental geneticists and developmental biologists we need the active participation of our readers, If you have reformation about methods developed in your lab or elsewhere why not share it with your colleagues through the Technical Tips section of Tre n d s in Genetics? Each month Technical Tips draws attention to such methods by presenting very brief articles. These do not attempt to provide all the information required to use the method but rather a clear outline of the method's claimed advantages and present and potential applications; readers can then look to the reference for complete details. The only exception to this general policy concerns descriptions of unpublished methods where more precise experimental details should be provided. Please send all information to: Trends i . G e n e t l u , Elsevier Publications Cambridge, 68 Hills Road. Cambridge CB2 1LA, UK, or call (0223) 315961.
November 1987, VoL 3, no. I1
the knowledge of the responsible oncoproteins. Targeting of antitumor drugs to the oncogene products or the signals generated by their expression could also best be tested in transgenic mice. References I Palmiter, R. D. and B~Ister, R. L. (1998) Annu. Rev. G ~ t . 20, 465-499 2 Varmus, H. E. (1984)Annu. Rev. Genet.
18, 553--612 3 Quaife, C. J. et al. (1987) Cell 48, 10231034 4 Andres, A. C. etal. (1987) Proc. Natl Aead. Sd. USA 84, 1299-1303 5 Sch0nenberger, C. A. et al. EMBO ]. (in press) 6 Adams, J. M. et at. (1985) Nature 318, 533-538 7 Langdon, W. Y., Harris, A. W., Cory, S. and Adams,J. M. (1986) Cell 47, 11-18 8 Leder, ,6. et aL (1986) Cell 45, 485--495 9 Sinn, E. etal. (1987) Cell 49, 465--475 I0 Bishop,J. M. (1985) Cell 42, 23-38 11 Land, H., Parada, L. F. and Weinberg, R. A. (1983) Science 222, 771-778 12 Klein, G. and Klein, E. (1985)lmmumol. Today6, 208-215 13 Slamon, D. J. et ai. (1987) Sdence 235, 177-182 practicable for everyday use in a busy multi-user laboratory. Dues any reader know of a procedure for ethidium bromide destruction that is both safe and practicable? B, L. C O H E N
University of Glasgow IRstitute of Genetics, Church Street, Glasgow GII 5]S. UK.
References 1 Trends Genet. 3, 176 (1987) 2 Lann, G. and Sansone, E. B. (1987)Anal. Biochem. 162, 453-458
REPRINTS and BACK ISSUES We can supply reprints of any article appearing in TIG at very reasonable rates. Please apply for details to: Production Manager, Elsevier Publications Cambridge, 68 Hills Road, Cambridge CB2 1LA, UK (minimum order 100) For information concerning orders for single complete issues of T/G please write to: T/G Back Issues, at the same address.
1987, Elsevier Pubhcaoons, Cambridge 0168- 9525/871502.00
onitor genic mice were mammary adenocarcinomas, followed by malignant lymphomas, salivary gland adenocarcinomas, Harderian gland hyperplasias and seminal vesicle neoplasms. It was found in these studies that the simultaneous expression of the myc and ras oncogenes enhanced tumor formation and reduced latency, but still did not seem to be sufficient for transformation in vivo. T h e onset of expression and tumor formation still diverge, the tumors are clonal and the expressing cell populations are not homogeneously transformed, suggesting that additional genetic events need to be postulated. The presence of consistent chromosomal translocations, amplifications of chromosomal segments or loss of specific loci might help in finding the genes involved in cooperative functions. Questions about the mechanism of cooperativity, e.g. the distinction between a synergistic
Ethidium bromide safety The recent brief report in T I G 1 of the study by Lurm and Sansone 2 of ethidium bromide destruction fails to point out one very disturbing aspect of their findings, namely that the products of ethidium bromide destruction by the widely used method of treatment with hypochlorite bleach are more mutagenic
and a sequential model of oncogene action, might become approachable through conditional oncogene expression using hormonally regulated, tissue specific transgene constructs. Conclusions The use of targeted myc and ras expression has yielded additional insights into the intricacies of the transformation process, but no general rules about the effects of these two oncogenes can be formulated. Since it is not practicable to test the effect of every oncogene in every tissue, future experiments might have to focus on the expression of oncogenes consistently found to be involved in a high percentage of naturally occurring tumors of a certain type (e.g. myc in lymphomas TM, c-erbB-2 in mammary carcinomas13). Transgenic mouse tumors induced by these oncogenes might provide valuable model systems for experimental treatments based on
(in the test used) than ethidium bromide itself. As safety adviser in this department, I am concerned to find an acceptable procedure for ethidium bromide decontamination of transilluminators, etc. However I consider that the alternative method of treatment with hypophosphorous acid/sodium nitrite, which is recommended by Luun and Sansone and which they observed to give complete conversion of ethidium bromide to non-mutagenic products, is not
Pool your useful hints through Technical Tips Technical Tips is a place where readers can exchange information about new experimental techniques. To make this section really useful to experimental geneticists and developmental biologists we need the active participation of our readers, If you have reformation about methods developed in your lab or elsewhere why not share it with your colleagues through the Technical Tips section of Tre n d s in Genetics? Each month Technical Tips draws attention to such methods by presenting very brief articles. These do not attempt to provide all the information required to use the method but rather a clear outline of the method's claimed advantages and present and potential applications; readers can then look to the reference for complete details. The only exception to this general policy concerns descriptions of unpublished methods where more precise experimental details should be provided. Please send all information to: Trends i . G e n e t l u , Elsevier Publications Cambridge, 68 Hills Road. Cambridge CB2 1LA, UK, or call (0223) 315961.
November 1987, VoL 3, no. I1
the knowledge of the responsible oncoproteins. Targeting of antitumor drugs to the oncogene products or the signals generated by their expression could also best be tested in transgenic mice. References I Palmiter, R. D. and B~Ister, R. L. (1998) Annu. Rev. G ~ t . 20, 465-499 2 Varmus, H. E. (1984)Annu. Rev. Genet.
18, 553--612 3 Quaife, C. J. et al. (1987) Cell 48, 10231034 4 Andres, A. C. etal. (1987) Proc. Natl Aead. Sd. USA 84, 1299-1303 5 Sch0nenberger, C. A. et al. EMBO ]. (in press) 6 Adams, J. M. et at. (1985) Nature 318, 533-538 7 Langdon, W. Y., Harris, A. W., Cory, S. and Adams,J. M. (1986) Cell 47, 11-18 8 Leder, ,6. et aL (1986) Cell 45, 485--495 9 Sinn, E. etal. (1987) Cell 49, 465--475 I0 Bishop,J. M. (1985) Cell 42, 23-38 11 Land, H., Parada, L. F. and Weinberg, R. A. (1983) Science 222, 771-778 12 Klein, G. and Klein, E. (1985)lmmumol. Today6, 208-215 13 Slamon, D. J. et ai. (1987) Sdence 235, 177-182 practicable for everyday use in a busy multi-user laboratory. Dues any reader know of a procedure for ethidium bromide destruction that is both safe and practicable? B, L. C O H E N
University of Glasgow IRstitute of Genetics, Church Street, Glasgow GII 5]S. UK.
References 1 Trends Genet. 3, 176 (1987) 2 Lann, G. and Sansone, E. B. (1987)Anal. Biochem. 162, 453-458
REPRINTS and BACK ISSUES We can supply reprints of any article appearing in TIG at very reasonable rates. Please apply for details to: Production Manager, Elsevier Publications Cambridge, 68 Hills Road, Cambridge CB2 1LA, UK (minimum order 100) For information concerning orders for single complete issues of T/G please write to: T/G Back Issues, at the same address.
1987, Elsevier Pubhcaoons, Cambridge 0168- 9525/871502.00