DIFFERENTIAL
INTERMITTENT
GERALD D. GRIFFIN,
RADIATION
THERAPY:
A CONCEPTUAL
MODEL
University Hospitals, Cleveland, Ohio 44106, USA.
SUMMARY
Cell membranes are made up of repeating units and subunits of various chemical moieties. It is proposed that these repeating units give each type of cell membrane a natural resonant frequency characteristic of that particular cell. It is further stipulated that this natural resonance is modifled by attached antigens, and that this modification is unique to each different tumor type and patient. A signal that is of the same frequency as the natural resonance of the cell membrane may then be used to excite the cell membrane to its natural or modified resonant frequency and lyse it, as well as any metastases with the same characteristic. This resonant frequency must first be determined by growing tumor cells in culture, and is likely to be unique to each patient. Possible other uses of an excitatory signal may be to break apart chemical moieties. The only requirement is that this excitatory signal be matched to the resonant frequency of the cell wall or moiety to be lysed. The excitatory signal may come from various sources-sonic, electrical, x-ray, radio frequency, laser or nuclear. But the problem which must be solved is devising a method for determining the resonant frequencies of cell membranes.
ACKNOWLEDGMENTS
partially characteristic of current radiation therapy. I will suggest a different approach and possible new areas of research.
My appreciation to Drs. Manuel Delfin Leon and Mariano Allen Cuaron, Instituto de Ciencias Biomedicas and Escuela de Medicina, Universidad Autonoma de Cd. Juarez, for support and encouragement; to Martin Weiner; Will Ferguson; and Bob Carbone, all of UACJ, for reading the manuscript and giving good criticism and advice; to Howell Runion, University of the Pacific, for instilling in his students the inquisitiveness and ability to ask questions that may advance knowledge, and especially for giving of himself to his students’ support in this process.
INTRODUCTION
There are two current primary modes of radiation treatment: x-rays and the various types of energy which are transmitted to the site of action via a beam. The basic concept of radiation therapy has not changed essentially since the days of its inception. However, much has been done to vary the modes of delivery and the types of energy emitted at the target site. X-ray therapy simply aims to kill the cells at the target site. Radiation therapy too has that goal but accomplishes it variously. For example, some sources are able to penetrate the skin and subcutaneous tissue without causing damage and then to emit different types of energy at the target site. Others simply “burn” their way to the target site. Still others are implanted surgically, and total body irradiation is yet another variation. These sophistications have not essentially changed the mode of radiation therapy. The disadvantages of conventional radiation and x-ray therapy are many, though much has been done to abate these. The major disadvantage is a gross lack of specificity for target cells. Unfortunately, all other tissue surrounding the target cells, and sometimes that tissue en route to the target cells is also damaged. This is obviously problematic. The major goal, then, to improve radiation therapy would be to improve its specificity for target cells. Implied is such specificity that therapy is tailored to each patient. This is 283
DIFFERENTIAL RADIATION THERAPY In order to describe the differential portion of Differential Intermittent Radiation Therapy (DIRT), I must review briefly the structure and nature of the cellular membrane. Gorter and Grendel(1) studied erythrocytes, found that the ratio of lipid layer in relation to the area of cell wall was approximately 2: 1 and suggested a two-layered membrane. (2) Danielli and Harvey (3) suggested the presence of lipid and aqueous phases and described the accompanying effects on permeability. Danielli and Davson (4) went on to suggest the paucimolecular theory of the cellular membrane which was substantiated by Robertson (5). It is known now that cell membranes are different for each type of cell, and consist of a unit tailored by the cell to fit its particular needs for permeability, metabolism, enzymatic activity and other requirements (6). The differences in membrane constituents have been worked out by Korn (7) for a number of membranes. Each cell carries a number of protein surface antigens. Each cell plasma membrane has a basic backbone of repeating constituents and subunits. Two characteristics are relevant to the discussion which follows. 1. The same repeating constituents are found in each cell of a tissue, but differ from tissue to tissue. 2. The cell surface antigens are specific to each type of cell. The principles set forth in this paper are addressed primarily to the latter. A characteristic of the cell membrane not mentioned includes what I feel to be an important property: membranal resonance. It is suggested that each different type of membrane with its repeating subunits has a natural resonant frequency. This frequency may be used advantageously in this conceptual therapeutic model. It is suggested that once the cell membrane is excited at its natural resonance by a predetermined signal, matched to the resonant frequency of the membrane, the cell membrane then lyses. It is felt that this natural resonant frequency is determined by the par-
titular repeating subunit of the cell which makes it unique to that cell.
MEMBRANAL ANTIGEN EFFECTS Each cell of a particular tissue has its own specific antigenic complement attached, and thus everyone may have unique membranal resonant frequencies. The effect of the attached antigens may be illustrated by an example. If one imagines a piece of metal of certain length, which is then stimulated by a signal matched to its natural resonant frequency, the metal will shatter once this frequency is reached. We can now take another piece of metal, identical to the first one, and attach to it various arms and pieces of diierent metal. If this is then stimulated by a signal matched to the resonant frequency of the first piece of metal, it will not shatter. The resonant frequency is altered by the attachment, and hence, a new resonant frequency must be sought. This change in frequency depends upon the nature of the attachments and the strength with which they are attached. Given the similar situation in a cellular membrane with repeating like subunits and a certain resonant frequency, one can surmise that this frequency too is altered by the attached antigens. It must be remembered that each of these antigenic profiles is host and tissue specific, and hence, confers upon the membrane a host and tissue specific resonant frequency. Now, if a neoplastic cell has a unique antigenic profile, it is immunologically different from its normal neighbor and its forbears in the same tissue. I suggest it may also be different in resonant frequency from these cells. This difference may present an opportunity for differential treatment. It has been shown that various viruses acting as oncogenic agents give tumors distinctly different antigenic profiles, characteristic of the virus, while chemically or radiation induced tumors have only minor differences antigenically which are not predictably related to the carcinogen (8). Klein has shown that several tumors induced by the same chemical agent are antigenically different and do not cross-react (9). These tumor specific antigens may or may not be necessary for the transformation of the cell to a neoplastic type (10,ll). ‘Work by Granlund and Ritts (12) has shown that some of these tumor antigens were not tumor specific by current definition, but rather were called simply “tumor associated.” However, in this paper, we need not concern ourselves with those problems. We need to take advantage of the fact that these tumor specific antigens do exist, and may confer upon the cell membrane a specific resonant frequency different from non-neoplastic tissue cells. Wallach (13) has pointed out already that cancer may be a membrane related disease. Among the characteristics he gives us as being particular to cancerous cells are new membrane bounded antigens and impaired cellular junctional complexes. He further states that these membranal changes may also be found in organelle membranes. In well differentiated tumors it seems true that metastases also have the same antigenic profile as that of the primary lesion and hence, may also have the same resonant membranal resonant frequency modified only by its new environment. Therefore, once the resonant frequency of the primary lesion, or even metastatic lesion, has been deter284
mined, treatment of both centers of neoplastic growth could consist of irradiating with the resonant frequency. Perhaps total body radiation would lyse only those cells that have that particular resonant frequency. Conventional radiotherapy has profound immunosuppressive effects (14) and the number of circulating T lymphocytes may be diminished for months or years after radiotherapy (15). A correlation between immunocompetence and prognosis of cancer therapy has also been found with the development of membranal antigenic profiles in various types of cancer (16).
RESONANT FREQUENCY DETERMINATION If one can determine the constituents of a particular cell membrane and the pattern with which they repeat and are linked, one may be able to begin to estimate the frequency at which this unit becomes resonant. To this end, one may consider simple irradiation experiments of tumor cultures vs. cultures of normal cells from the same tissue. Extremely short laser pulses (less than l/set) may be useful. Wave lengths in the ultraviolet and shorter spectrum including radiofrequency energy may also be tried. The two tissue cultures would have to be radiated simultaneously in order to be able to detect any difference in resonant frequency. The frequency at which the moiety absorbs energy (resonates) is the point which has to be elicited. There might be qualitative differences in susceptibility to a particular frequency or quantitative differences in the damage produced or in the time required to produce damage. Obviously much work will have to be done on the techniques involved.
INTERMITTENT RADIATION THERAPY In a sophistication of radiotherapeutic techniques, the cell life cycle has been studied in an attempt to determine which phase of the cycle is best during which to irradiate tn halt cell growth. I suggest that differential radiation as discussed may be combined with this intermittent mode of therapy, hence leading to the conceptual model of Differential Intermittent Radiation Therapy (DIRT).
CONCLUSION Differential Intermittent Radiation Therapy (DIRT) has been proposed as a hypothetical treatment for neoplastic cells. It may also be a viable tool for lysing bacterial cell walls, viral particles, leukocytes, complement-antibody complexes, chemotactic moieties, the top layers of atherosclerotic plaques, and those other molecular moieties which may be excited by a resonant signal. There are undoubtedly many problems ahead in applying DIRT and the first essential must be a method for determining the resonant frequencies of cells. REFERENCES
1. Gorter E, Grendel F. On bimolecular layers of lipoids on the chromocytes of the blood. J Expti Med. 41, 439-443 1925 .2 Gorter E, Grendel F. Bimolecular layers of lipins on the chromocytes of blood. Proc K Akad Wetensch. 29, 314-317, 1926 3. Danielli JF, Harvey EN. The tension at the surface of mackerel egg oil, with remarks on the nature of the cell surface. J Cell Comp Physiol. 5, 483-494, 1934
4.
5.
Danielli JF, Davson H. A contribution to the theory of permeability of thin films. J Cell Comp Physiol. 495-507 1934 Robertson JD. The ultrastructure of cell membranes and their &$;atives. Biochem Sot Symp. 16, l-40 Cambridge, England,
12. 13.
6. 7. 8. 9. 10. II.
Ashworth LAE, Green C, Plasma membranes: Phosphohpid and sterol content. Science 151. 210-211 1966 Kern ED. Structure of biological membranes. Science 153, 149 l1498. 1966 Robbins SL. in Pathologic basis of disease, ~140, WB Saunders Co, Philadelphia, 1974. Klein G. Experimental studies in tumor immunoloav.__ Fed Proceedings 28, ‘1739. 1969 Law LW. Studies of the significance of tumor antigens in induction and repression of neoplastic disease. Cancer Res. 29, 1, 1969 Hare JD. Transplant immunity to polyoma virus induced tumor
14.
15.
16.
285
cells, IV, A polyoma strain defective in transplant antigen induction. Virology 31, 625, 1967 Granlund DJ, Ritts RE. Soluble proteins of human bronchiogenic carcinomas. Mav Clin Proc. 41. 19-27. 1976 Wallach DFH. Cellular membranes and tumor behavior. Proc Natl Acad Sci. 61, 868, 1968 Hersh EM. Gutterman JU. Mavligit G. et al. Host defense. chemical immunosuppression and the transplant recipient. Transpi Proc. 5, 1191-1196, 1973 Stjernsward J, Jondal M, Vanky F, et al. Lymphopenia and change in destruction of human B and T lymphocytes in peripheral blood induced by irradiation for mammary carcinoma. Lancet 1, 1352. 1356, 1972 Hersh EM. Gutterman JU, Mavligit G. Assessment of immunocompetence in the routine evaluation of the cancer patient. South Med J. 69, 356-359. 1976
INTERMITTENT
GERALD D. GRIFFIN,
RADIATION
THERAPY:
A CONCEPTUAL
MODEL
University Hospitals, Cleveland, Ohio 44106, USA.
SUMMARY
Cell membranes are made up of repeating units and subunits of various chemical moieties. It is proposed that these repeating units give each type of cell membrane a natural resonant frequency characteristic of that particular cell. It is further stipulated that this natural resonance is modifled by attached antigens, and that this modification is unique to each different tumor type and patient. A signal that is of the same frequency as the natural resonance of the cell membrane may then be used to excite the cell membrane to its natural or modified resonant frequency and lyse it, as well as any metastases with the same characteristic. This resonant frequency must first be determined by growing tumor cells in culture, and is likely to be unique to each patient. Possible other uses of an excitatory signal may be to break apart chemical moieties. The only requirement is that this excitatory signal be matched to the resonant frequency of the cell wall or moiety to be lysed. The excitatory signal may come from various sources-sonic, electrical, x-ray, radio frequency, laser or nuclear. But the problem which must be solved is devising a method for determining the resonant frequencies of cell membranes.
ACKNOWLEDGMENTS
partially characteristic of current radiation therapy. I will suggest a different approach and possible new areas of research.
My appreciation to Drs. Manuel Delfin Leon and Mariano Allen Cuaron, Instituto de Ciencias Biomedicas and Escuela de Medicina, Universidad Autonoma de Cd. Juarez, for support and encouragement; to Martin Weiner; Will Ferguson; and Bob Carbone, all of UACJ, for reading the manuscript and giving good criticism and advice; to Howell Runion, University of the Pacific, for instilling in his students the inquisitiveness and ability to ask questions that may advance knowledge, and especially for giving of himself to his students’ support in this process.
INTRODUCTION
There are two current primary modes of radiation treatment: x-rays and the various types of energy which are transmitted to the site of action via a beam. The basic concept of radiation therapy has not changed essentially since the days of its inception. However, much has been done to vary the modes of delivery and the types of energy emitted at the target site. X-ray therapy simply aims to kill the cells at the target site. Radiation therapy too has that goal but accomplishes it variously. For example, some sources are able to penetrate the skin and subcutaneous tissue without causing damage and then to emit different types of energy at the target site. Others simply “burn” their way to the target site. Still others are implanted surgically, and total body irradiation is yet another variation. These sophistications have not essentially changed the mode of radiation therapy. The disadvantages of conventional radiation and x-ray therapy are many, though much has been done to abate these. The major disadvantage is a gross lack of specificity for target cells. Unfortunately, all other tissue surrounding the target cells, and sometimes that tissue en route to the target cells is also damaged. This is obviously problematic. The major goal, then, to improve radiation therapy would be to improve its specificity for target cells. Implied is such specificity that therapy is tailored to each patient. This is 283
DIFFERENTIAL RADIATION THERAPY In order to describe the differential portion of Differential Intermittent Radiation Therapy (DIRT), I must review briefly the structure and nature of the cellular membrane. Gorter and Grendel(1) studied erythrocytes, found that the ratio of lipid layer in relation to the area of cell wall was approximately 2: 1 and suggested a two-layered membrane. (2) Danielli and Harvey (3) suggested the presence of lipid and aqueous phases and described the accompanying effects on permeability. Danielli and Davson (4) went on to suggest the paucimolecular theory of the cellular membrane which was substantiated by Robertson (5). It is known now that cell membranes are different for each type of cell, and consist of a unit tailored by the cell to fit its particular needs for permeability, metabolism, enzymatic activity and other requirements (6). The differences in membrane constituents have been worked out by Korn (7) for a number of membranes. Each cell carries a number of protein surface antigens. Each cell plasma membrane has a basic backbone of repeating constituents and subunits. Two characteristics are relevant to the discussion which follows. 1. The same repeating constituents are found in each cell of a tissue, but differ from tissue to tissue. 2. The cell surface antigens are specific to each type of cell. The principles set forth in this paper are addressed primarily to the latter. A characteristic of the cell membrane not mentioned includes what I feel to be an important property: membranal resonance. It is suggested that each different type of membrane with its repeating subunits has a natural resonant frequency. This frequency may be used advantageously in this conceptual therapeutic model. It is suggested that once the cell membrane is excited at its natural resonance by a predetermined signal, matched to the resonant frequency of the membrane, the cell membrane then lyses. It is felt that this natural resonant frequency is determined by the par-
titular repeating subunit of the cell which makes it unique to that cell.
MEMBRANAL ANTIGEN EFFECTS Each cell of a particular tissue has its own specific antigenic complement attached, and thus everyone may have unique membranal resonant frequencies. The effect of the attached antigens may be illustrated by an example. If one imagines a piece of metal of certain length, which is then stimulated by a signal matched to its natural resonant frequency, the metal will shatter once this frequency is reached. We can now take another piece of metal, identical to the first one, and attach to it various arms and pieces of diierent metal. If this is then stimulated by a signal matched to the resonant frequency of the first piece of metal, it will not shatter. The resonant frequency is altered by the attachment, and hence, a new resonant frequency must be sought. This change in frequency depends upon the nature of the attachments and the strength with which they are attached. Given the similar situation in a cellular membrane with repeating like subunits and a certain resonant frequency, one can surmise that this frequency too is altered by the attached antigens. It must be remembered that each of these antigenic profiles is host and tissue specific, and hence, confers upon the membrane a host and tissue specific resonant frequency. Now, if a neoplastic cell has a unique antigenic profile, it is immunologically different from its normal neighbor and its forbears in the same tissue. I suggest it may also be different in resonant frequency from these cells. This difference may present an opportunity for differential treatment. It has been shown that various viruses acting as oncogenic agents give tumors distinctly different antigenic profiles, characteristic of the virus, while chemically or radiation induced tumors have only minor differences antigenically which are not predictably related to the carcinogen (8). Klein has shown that several tumors induced by the same chemical agent are antigenically different and do not cross-react (9). These tumor specific antigens may or may not be necessary for the transformation of the cell to a neoplastic type (10,ll). ‘Work by Granlund and Ritts (12) has shown that some of these tumor antigens were not tumor specific by current definition, but rather were called simply “tumor associated.” However, in this paper, we need not concern ourselves with those problems. We need to take advantage of the fact that these tumor specific antigens do exist, and may confer upon the cell membrane a specific resonant frequency different from non-neoplastic tissue cells. Wallach (13) has pointed out already that cancer may be a membrane related disease. Among the characteristics he gives us as being particular to cancerous cells are new membrane bounded antigens and impaired cellular junctional complexes. He further states that these membranal changes may also be found in organelle membranes. In well differentiated tumors it seems true that metastases also have the same antigenic profile as that of the primary lesion and hence, may also have the same resonant membranal resonant frequency modified only by its new environment. Therefore, once the resonant frequency of the primary lesion, or even metastatic lesion, has been deter284
mined, treatment of both centers of neoplastic growth could consist of irradiating with the resonant frequency. Perhaps total body radiation would lyse only those cells that have that particular resonant frequency. Conventional radiotherapy has profound immunosuppressive effects (14) and the number of circulating T lymphocytes may be diminished for months or years after radiotherapy (15). A correlation between immunocompetence and prognosis of cancer therapy has also been found with the development of membranal antigenic profiles in various types of cancer (16).
RESONANT FREQUENCY DETERMINATION If one can determine the constituents of a particular cell membrane and the pattern with which they repeat and are linked, one may be able to begin to estimate the frequency at which this unit becomes resonant. To this end, one may consider simple irradiation experiments of tumor cultures vs. cultures of normal cells from the same tissue. Extremely short laser pulses (less than l/set) may be useful. Wave lengths in the ultraviolet and shorter spectrum including radiofrequency energy may also be tried. The two tissue cultures would have to be radiated simultaneously in order to be able to detect any difference in resonant frequency. The frequency at which the moiety absorbs energy (resonates) is the point which has to be elicited. There might be qualitative differences in susceptibility to a particular frequency or quantitative differences in the damage produced or in the time required to produce damage. Obviously much work will have to be done on the techniques involved.
INTERMITTENT RADIATION THERAPY In a sophistication of radiotherapeutic techniques, the cell life cycle has been studied in an attempt to determine which phase of the cycle is best during which to irradiate tn halt cell growth. I suggest that differential radiation as discussed may be combined with this intermittent mode of therapy, hence leading to the conceptual model of Differential Intermittent Radiation Therapy (DIRT).
CONCLUSION Differential Intermittent Radiation Therapy (DIRT) has been proposed as a hypothetical treatment for neoplastic cells. It may also be a viable tool for lysing bacterial cell walls, viral particles, leukocytes, complement-antibody complexes, chemotactic moieties, the top layers of atherosclerotic plaques, and those other molecular moieties which may be excited by a resonant signal. There are undoubtedly many problems ahead in applying DIRT and the first essential must be a method for determining the resonant frequencies of cells. REFERENCES
1. Gorter E, Grendel F. On bimolecular layers of lipoids on the chromocytes of the blood. J Expti Med. 41, 439-443 1925 .2 Gorter E, Grendel F. Bimolecular layers of lipins on the chromocytes of blood. Proc K Akad Wetensch. 29, 314-317, 1926 3. Danielli JF, Harvey EN. The tension at the surface of mackerel egg oil, with remarks on the nature of the cell surface. J Cell Comp Physiol. 5, 483-494, 1934
4.
5.
Danielli JF, Davson H. A contribution to the theory of permeability of thin films. J Cell Comp Physiol. 495-507 1934 Robertson JD. The ultrastructure of cell membranes and their &$;atives. Biochem Sot Symp. 16, l-40 Cambridge, England,
12. 13.
6. 7. 8. 9. 10. II.
Ashworth LAE, Green C, Plasma membranes: Phosphohpid and sterol content. Science 151. 210-211 1966 Kern ED. Structure of biological membranes. Science 153, 149 l1498. 1966 Robbins SL. in Pathologic basis of disease, ~140, WB Saunders Co, Philadelphia, 1974. Klein G. Experimental studies in tumor immunoloav.__ Fed Proceedings 28, ‘1739. 1969 Law LW. Studies of the significance of tumor antigens in induction and repression of neoplastic disease. Cancer Res. 29, 1, 1969 Hare JD. Transplant immunity to polyoma virus induced tumor
14.
15.
16.
285
cells, IV, A polyoma strain defective in transplant antigen induction. Virology 31, 625, 1967 Granlund DJ, Ritts RE. Soluble proteins of human bronchiogenic carcinomas. Mav Clin Proc. 41. 19-27. 1976 Wallach DFH. Cellular membranes and tumor behavior. Proc Natl Acad Sci. 61, 868, 1968 Hersh EM. Gutterman JU. Mavligit G. et al. Host defense. chemical immunosuppression and the transplant recipient. Transpi Proc. 5, 1191-1196, 1973 Stjernsward J, Jondal M, Vanky F, et al. Lymphopenia and change in destruction of human B and T lymphocytes in peripheral blood induced by irradiation for mammary carcinoma. Lancet 1, 1352. 1356, 1972 Hersh EM. Gutterman JU, Mavligit G. Assessment of immunocompetence in the routine evaluation of the cancer patient. South Med J. 69, 356-359. 1976
