Cancer Letters, 5 (1978) 22,5--225 © Elsevier/North-Holland Scientific Publishers Ltd,
225
PANCREATIC DUCTULrrIs IN SYRIAN GOLD~.'N HAMSTE]~,S BEA'RE~'G HOMOLOGOUS TR.~uNSPLANTABLE PANCP~EATIC ADENOCARCINOMAS RICHARD RUNGF,,MICHIHITOTAKAHASHIand PARVIZ POUR Eppley Institute for t~esearch '~ Cancer, University of Nebr~,_ Medical Center, 42rid and Dewey Avenue, Omaha, Nebra~t~a 6~105 (U.S.A.)
(Received 9 Ju~e 1978) (Accepted ~ June 1978)
SUMMARY
A highly specific pancreatitis primarily affecting the intralobu]ar arid intrainsulax ductules has been demonstrated in Syrian golden hamsters bearing homologous, non-syngeneic, tramsplantable pancreatic adenocarcinomas induced by N.nitrosobis(2-oxopropyl)amine (BOP). The ductulitis provides further evidence that induced pancreatic neoplasms ol~ginate from ductules.
L~TRODUCTION
The induction of pancreatic neoplasms in Syrian golden hamsters by specific nitrosaminas [3--5] provides a tool for investigating various aspects o f pane:teatic caminogenesis. The significant advantage of this model is the close resemblance of ~he induced tumors, morphologically and biologically', to tumol~ occur~ng in man [3]. Studies of the histogenesis of pancleatic neoplasms ~rlL this model indicate that the ductu]es, especially those of intra~lsul~ origin, ~ge ~he primary target cells of the relatively specific pancr~.~atic carcinogen BOP [[6,9]. The p~sent report on pancreatic alterations in recipients of homologous, non-syngeneic, transplantable, BOP-induced, pancreatic adcnocm~cinomas supports the theory of a ductular origia of the induced neopla.~ms. MATER~.LSAND METHODS Initially, 5 male, 8-week.old random-bred Syrian hamster~; from the Eppley Colony were inoculated subcutaneo~fly in the interscapular area with m i n c ~ tissue f~om a single BOP-induced l~-ancreatic adenocaxeinom~ [5]. ]In 3 out ef Abbrevia~on: BO}~, .~[-nitro~obis(2~xypropyl)amine.
226 5 inoculated hamsters o f the first generation, the t u m o r grew within 6 weeks. In genera*Aon.~ 2--10, each composed o f 10 an:hnals, the t u m o r yield was 100%. A t u m o r line ha~ been m ~ t a / n e d b y successive inoc~lation into 3 hams~iers p e r gen~ration and is currently in its 16th passage. Histologically, the ~arnor has mahttah~ed its basic pattern. Tumc.r recipients were k e p t in individual cages, fed Wayne p e t e r e d diet ~md w a t e r ad libi~um, and observed, until d ~ t h or killed when moribund. Animals were cov.~pletely autopsied, and ol~gan.~were fixed in 10% buffered fonnalin, processed, and s t s ~ e d with hematoxy~£.~ and eosin according to conventional methods. The pancreas was cut; in~o s~ep sections. RESULTS Detailed information on growth, morpho].ogy, and biologic behavior of the original wld transplanted tumors will be desc~ibed in a later publication. The present reF,ort concentrates on alterations o f the pancreas in t u m o r recipients. A n a t o m i c and histologic characteristics of the pancreas in this specie~ have been de.~clibed previously [6,8~. I~ 4 o u t o.f 45 hamsters (9%) bearing tumors o f different generations, a peculiar form o f pancreatitis occurred; however, there wa~' no p~'eferential involvement o f specific pancreat1.c segments. The pancreatitis consisted o f an acute inflar,.~matory infiltrate o f varyir~g severity around c r within ductules (Figs. 1 and 2). In some regions., the hyperp].astic,
Fig. 1. I~)lated segmental acute iv fl~Lmrnatlonof a pancreatic ir~i:ralobularductu[e (top) and an islet. Note appareat eontinuati,0n of granulocytic fLnfiltratefrom ductules into islet. H ,~: E, x65.
227
Fig. 2. Marke~ focal acute duc~;uliti~.Polymorp,honucle~ g,,:an~locy'tesare either ~xranged around and separated from the ductule by zone of edema ~left)or have migrated within ductule (~ight). H & E, × 130.
and on occasiion, proliferated ductular cells were surrounded by or inte~.~lingled with a scant infiltration oi' gmnulocytes. In other areas, i)he ductules were essentially destroyed, apparently by She heavy infiltration of polymo~honuclear leukocytes; while within the same pancree~, there were areas with regular patterns and no evidence of inflmnmation. L~he degree of involvemen~I varied among affected animals, and there was ~.o relationship be;~;ween ~he degree or extent o~'inflammation and the number c,f',~umorpassages or actu~J size of ~umors. However, in all 4 anhna~s the carcinoma had metastasized iLnt~
the lungs. The inflammatory proces~ appezJ,,ed to beg~r~ as a hyperemia and ~r~fld edema surrounding the ductules, folLlowed by increas!.ng infiltratior) of po!~ymorphonuc!ear leukocytes. ]in I anhnal, 1,he inflamma'~ion was partially chror.dc, being marked by chronic inflammatory cell~ (lyrnphocytes and plasma cells) and early fibrous tissue deposition which extended to neighboring a'~rophic acini. The Jinflammation involved primarily the intra]obular ductules and some islets. The latter condition represent~d inflammation of the intr~nsulm" ductulc~,as previously described [4], since inflamed ductules could be tbllowed ~n~o the islets {Fig. I). Involvement of interlobut.'.;.:ducts and major ducts wa,~ seen occasionally but in extremely circumscribed ~Lreas. Occasional ac~ar cell degeneration was confined to the close pro:~'imity of the involved ductule~.
228
Fig. 3 A c u t e i n f l ~ a r a a t i o n within duetule a n d i.slet. It & E, × 250.
l[~ig. 4. Mark, ~d in:tlammatlon a b o u t intralobular duc~ule. H & E~ × ~:~5,9.
229 Alteration of the common pancreatic and commc, n ducts was n o t evident. The pancreatic inflammation occurred in and about the pancreatic ductules. The small blood vessels (particuh~ly the arteries) wi~ich ~ccompany the,;e ductular structures showed no evidence of the acute?, inflammati,,~.~ sometimes seen in Arthus-type reactions to soluble antigens. If this lesion does represent zm autoimmune pancreatic ductulitis, the responsible antigen is app¢centiy fixed to tl~e surface of the epithelial cell. Careful ex~aination of the remai~aing tissues in these anims,ls revealed n o areas of inflammation. The s~!bcutan,eously implanted turnouts d:id show infiltration of their peripheral portions by acute and chronic inflammatory cells. This peripheral infl~mamation was seen in virtually ~1 of the animals. The in:flammatory respon,,~e to metastatic loci of tumors was considerably less than that, seen in the pri~nary i.,~p]an~ed tumors. The 4 hamsters whieih demonstrated ductulitis had pulmonary metastases which exhibited scanty inflammation. DISCUSSION T h e exact m e c h a n i s m for induction of such a speciJ!ic pancreatit, is is not k n o w n . Howevcr, an i m m u n o l o ~ c ~ etiology is possible, M a n y turnom~ retain s o m e of the ~mtigens normally present on the ~ell type f~'om vchich they c~.'igin-
r~a~ [7]. A hos~ response to these antigens might result in a cross-reacl~,ion with no~vaal host pancreatic ductular constituents. If this we,re the mechanis~m ir.~volved, it would be strongly supportive evidence for the ductulm" origi~n of these tumors [1,2,10]. Further studies will be completecl to delineate, the etiology of this peculiar ductutitis. REFERENCES
i
2 3 4 5
Freund, J. (1953) .~.~permatogene~isin the ~:inea pig induced by testieular tissue and adjuvants. J. Exp. Med., 97,711--725. Old, L. (1977) Cancer immunology. Sci. Am., 236, 82--79. Pour, P., Mohr, U., Cardesa, A., Althoff, J. and Kruf~er,F.W. (1975) Pancreatic neoplasms in an animal model: Morphological, biological and comparative s~udies. Cancer, 36,379--389. Pour, P., Altboff, J., Ginge]l,R., Kupper, R., Kruger, F. and MohL U. (19'76)~-Nitrosobis(2-acetoxypropyl)amineas a ~'urthcrpancreatic carcinogen it~ Syrian golderL hamsters, Cancer Res., 36, 2877--2884. Pour, P., Althoff, J., Kruger, F.W. and Mohr, U. (1977) A potent pancreatic eareivogen ira Syrian hamsters: N-nitrosobis(2-oxopropy~)amine.J. Natl. Cancer Inst.. 58,144,9-1,153.
6 Pour, P. (1978) Evidence of a relationshipbetween Isletsof Langerhans ~td due~l cells i~npancreatic ductal neoplasms. L Experimental study. ,~n. J. Paths/.,in ~a-ess. 7 t3chwenSker, F. (1934) The antibody response of rabbi~s to inj,eetionsof irnmulsioJnsand ex~.ractso£hemologou~ brain.J. Exp. Med, 60,559--574. 8 Takahashi, M., Pour, P., ~.~Ithof£,J. and Donnelly, T. (1977) The paacreas o£ the Sy~rian hamster (Mesocticetusa~tus). L Amatomic~d study. Lab. Anita. Sci.,27,336~342~ 9 T~:ah~shi~M~ur~P.~`dth~ff~J~andD~mle~ly~T.~1978)Sequan".i~lalterat~n`~)Ithe pancreas during ductal c#reinogenesis in Syrian hamsters. C~meer Res., in press. 10 Witvbsky, E. (1956) Studies on organ apecifici~Ly.J. Immunol., 7~, 408-,116.
225
PANCREATIC DUCTULrrIs IN SYRIAN GOLD~.'N HAMSTE]~,S BEA'RE~'G HOMOLOGOUS TR.~uNSPLANTABLE PANCP~EATIC ADENOCARCINOMAS RICHARD RUNGF,,MICHIHITOTAKAHASHIand PARVIZ POUR Eppley Institute for t~esearch '~ Cancer, University of Nebr~,_ Medical Center, 42rid and Dewey Avenue, Omaha, Nebra~t~a 6~105 (U.S.A.)
(Received 9 Ju~e 1978) (Accepted ~ June 1978)
SUMMARY
A highly specific pancreatitis primarily affecting the intralobu]ar arid intrainsulax ductules has been demonstrated in Syrian golden hamsters bearing homologous, non-syngeneic, tramsplantable pancreatic adenocarcinomas induced by N.nitrosobis(2-oxopropyl)amine (BOP). The ductulitis provides further evidence that induced pancreatic neoplasms ol~ginate from ductules.
L~TRODUCTION
The induction of pancreatic neoplasms in Syrian golden hamsters by specific nitrosaminas [3--5] provides a tool for investigating various aspects o f pane:teatic caminogenesis. The significant advantage of this model is the close resemblance of ~he induced tumors, morphologically and biologically', to tumol~ occur~ng in man [3]. Studies of the histogenesis of pancleatic neoplasms ~rlL this model indicate that the ductu]es, especially those of intra~lsul~ origin, ~ge ~he primary target cells of the relatively specific pancr~.~atic carcinogen BOP [[6,9]. The p~sent report on pancreatic alterations in recipients of homologous, non-syngeneic, transplantable, BOP-induced, pancreatic adcnocm~cinomas supports the theory of a ductular origia of the induced neopla.~ms. MATER~.LSAND METHODS Initially, 5 male, 8-week.old random-bred Syrian hamster~; from the Eppley Colony were inoculated subcutaneo~fly in the interscapular area with m i n c ~ tissue f~om a single BOP-induced l~-ancreatic adenocaxeinom~ [5]. ]In 3 out ef Abbrevia~on: BO}~, .~[-nitro~obis(2~xypropyl)amine.
226 5 inoculated hamsters o f the first generation, the t u m o r grew within 6 weeks. In genera*Aon.~ 2--10, each composed o f 10 an:hnals, the t u m o r yield was 100%. A t u m o r line ha~ been m ~ t a / n e d b y successive inoc~lation into 3 hams~iers p e r gen~ration and is currently in its 16th passage. Histologically, the ~arnor has mahttah~ed its basic pattern. Tumc.r recipients were k e p t in individual cages, fed Wayne p e t e r e d diet ~md w a t e r ad libi~um, and observed, until d ~ t h or killed when moribund. Animals were cov.~pletely autopsied, and ol~gan.~were fixed in 10% buffered fonnalin, processed, and s t s ~ e d with hematoxy~£.~ and eosin according to conventional methods. The pancreas was cut; in~o s~ep sections. RESULTS Detailed information on growth, morpho].ogy, and biologic behavior of the original wld transplanted tumors will be desc~ibed in a later publication. The present reF,ort concentrates on alterations o f the pancreas in t u m o r recipients. A n a t o m i c and histologic characteristics of the pancreas in this specie~ have been de.~clibed previously [6,8~. I~ 4 o u t o.f 45 hamsters (9%) bearing tumors o f different generations, a peculiar form o f pancreatitis occurred; however, there wa~' no p~'eferential involvement o f specific pancreat1.c segments. The pancreatitis consisted o f an acute inflar,.~matory infiltrate o f varyir~g severity around c r within ductules (Figs. 1 and 2). In some regions., the hyperp].astic,
Fig. 1. I~)lated segmental acute iv fl~Lmrnatlonof a pancreatic ir~i:ralobularductu[e (top) and an islet. Note appareat eontinuati,0n of granulocytic fLnfiltratefrom ductules into islet. H ,~: E, x65.
227
Fig. 2. Marke~ focal acute duc~;uliti~.Polymorp,honucle~ g,,:an~locy'tesare either ~xranged around and separated from the ductule by zone of edema ~left)or have migrated within ductule (~ight). H & E, × 130.
and on occasiion, proliferated ductular cells were surrounded by or inte~.~lingled with a scant infiltration oi' gmnulocytes. In other areas, i)he ductules were essentially destroyed, apparently by She heavy infiltration of polymo~honuclear leukocytes; while within the same pancree~, there were areas with regular patterns and no evidence of inflmnmation. L~he degree of involvemen~I varied among affected animals, and there was ~.o relationship be;~;ween ~he degree or extent o~'inflammation and the number c,f',~umorpassages or actu~J size of ~umors. However, in all 4 anhna~s the carcinoma had metastasized iLnt~
the lungs. The inflammatory proces~ appezJ,,ed to beg~r~ as a hyperemia and ~r~fld edema surrounding the ductules, folLlowed by increas!.ng infiltratior) of po!~ymorphonuc!ear leukocytes. ]in I anhnal, 1,he inflamma'~ion was partially chror.dc, being marked by chronic inflammatory cell~ (lyrnphocytes and plasma cells) and early fibrous tissue deposition which extended to neighboring a'~rophic acini. The Jinflammation involved primarily the intra]obular ductules and some islets. The latter condition represent~d inflammation of the intr~nsulm" ductulc~,as previously described [4], since inflamed ductules could be tbllowed ~n~o the islets {Fig. I). Involvement of interlobut.'.;.:ducts and major ducts wa,~ seen occasionally but in extremely circumscribed ~Lreas. Occasional ac~ar cell degeneration was confined to the close pro:~'imity of the involved ductule~.
228
Fig. 3 A c u t e i n f l ~ a r a a t i o n within duetule a n d i.slet. It & E, × 250.
l[~ig. 4. Mark, ~d in:tlammatlon a b o u t intralobular duc~ule. H & E~ × ~:~5,9.
229 Alteration of the common pancreatic and commc, n ducts was n o t evident. The pancreatic inflammation occurred in and about the pancreatic ductules. The small blood vessels (particuh~ly the arteries) wi~ich ~ccompany the,;e ductular structures showed no evidence of the acute?, inflammati,,~.~ sometimes seen in Arthus-type reactions to soluble antigens. If this lesion does represent zm autoimmune pancreatic ductulitis, the responsible antigen is app¢centiy fixed to tl~e surface of the epithelial cell. Careful ex~aination of the remai~aing tissues in these anims,ls revealed n o areas of inflammation. The s~!bcutan,eously implanted turnouts d:id show infiltration of their peripheral portions by acute and chronic inflammatory cells. This peripheral infl~mamation was seen in virtually ~1 of the animals. The in:flammatory respon,,~e to metastatic loci of tumors was considerably less than that, seen in the pri~nary i.,~p]an~ed tumors. The 4 hamsters whieih demonstrated ductulitis had pulmonary metastases which exhibited scanty inflammation. DISCUSSION T h e exact m e c h a n i s m for induction of such a speciJ!ic pancreatit, is is not k n o w n . Howevcr, an i m m u n o l o ~ c ~ etiology is possible, M a n y turnom~ retain s o m e of the ~mtigens normally present on the ~ell type f~'om vchich they c~.'igin-
r~a~ [7]. A hos~ response to these antigens might result in a cross-reacl~,ion with no~vaal host pancreatic ductular constituents. If this we,re the mechanis~m ir.~volved, it would be strongly supportive evidence for the ductulm" origi~n of these tumors [1,2,10]. Further studies will be completecl to delineate, the etiology of this peculiar ductutitis. REFERENCES
i
2 3 4 5
Freund, J. (1953) .~.~permatogene~isin the ~:inea pig induced by testieular tissue and adjuvants. J. Exp. Med., 97,711--725. Old, L. (1977) Cancer immunology. Sci. Am., 236, 82--79. Pour, P., Mohr, U., Cardesa, A., Althoff, J. and Kruf~er,F.W. (1975) Pancreatic neoplasms in an animal model: Morphological, biological and comparative s~udies. Cancer, 36,379--389. Pour, P., Altboff, J., Ginge]l,R., Kupper, R., Kruger, F. and MohL U. (19'76)~-Nitrosobis(2-acetoxypropyl)amineas a ~'urthcrpancreatic carcinogen it~ Syrian golderL hamsters, Cancer Res., 36, 2877--2884. Pour, P., Althoff, J., Kruger, F.W. and Mohr, U. (1977) A potent pancreatic eareivogen ira Syrian hamsters: N-nitrosobis(2-oxopropy~)amine.J. Natl. Cancer Inst.. 58,144,9-1,153.
6 Pour, P. (1978) Evidence of a relationshipbetween Isletsof Langerhans ~td due~l cells i~npancreatic ductal neoplasms. L Experimental study. ,~n. J. Paths/.,in ~a-ess. 7 t3chwenSker, F. (1934) The antibody response of rabbi~s to inj,eetionsof irnmulsioJnsand ex~.ractso£hemologou~ brain.J. Exp. Med, 60,559--574. 8 Takahashi, M., Pour, P., ~.~Ithof£,J. and Donnelly, T. (1977) The paacreas o£ the Sy~rian hamster (Mesocticetusa~tus). L Amatomic~d study. Lab. Anita. Sci.,27,336~342~ 9 T~:ah~shi~M~ur~P.~`dth~ff~J~andD~mle~ly~T.~1978)Sequan".i~lalterat~n`~)Ithe pancreas during ductal c#reinogenesis in Syrian hamsters. C~meer Res., in press. 10 Witvbsky, E. (1956) Studies on organ apecifici~Ly.J. Immunol., 7~, 408-,116.
