270 Abstracts/Lung Cancer 10 (1993) 266-286

Carciaoembryonic antigen (CEA) is o”e of the most hap&ant tllmour markers in the maongemenf of huna” carcinoma, including ltmg cancer. So far, however. because of the “onspecificity of lati-CEA potibodies, it reties unclear whether the experimental -re”ae”ts of CEA expression really reflect genuine CEA. I” normal lung, nonspecific cross reacting antigen (NCA) has been described as P major component of CEA-related a”tigcos. Recently isolated CEA and NCA cDNA clonesenabledus toanalyseCEAandNCAexpressiwofb vivohunour specimens and tumourcell lines at mRNA levels. NCA--itic mRNA (but not CEA-specific mRNA) was detected in all “omul lung tissuea examined. Of21 lung cancer tissuespecimens”i”eexprwsedboth NCA and CEA and five expressed only NCA. Of 16 tunow cell lines, two expressed only NCA mid one expressed both NCA a”d CEA, although its level of CEA ~IRNA was weaker thm that of NCA mRNA. Therefore, CEA-related naRNA expression was always accanpmied by NCA mRNAexpressio”; therewerem,casesofCEAmRNAexpressio” alone. These fmdings suggest that NCA is P major member of the CEA- related gene fanily expressed i” lung cancer.

A~onofaCD~~~deglyeosrlPtrdlidrrA-ehpini inmarm~o~nnd~v~modelsdsmrllall-lunge x-t Zangemeister-Wittke U, Leimwu~ H-P, Waibel R, Wawnyncxak EJ. Stahel RA. Division ofOnmlogy, Universify Hospiral. 8091 Zuridt. Iot J Cmcer 1993;53:521-8

TbetherapeuticefficpcyofPnimmunotoxin,SWAll-SPDBdg.ricin A chaii, recog”izing the leukocyte-differentiation Mtige” CD24, ww evaluated against SCLC cell lines in tissue culture a”d in 2 nude-mouse models. The first model used convmtionsl OX. solid-ttmmrxewgmfls. The second used smpll tumor-ceil deposits established in S.C. bnplpntea sponge matrices pod allowed us to directly estimpce thekilling efficbmcy of tbe immunotoxin under experimentally &t&d conditions in viva. It also mimics the clinical setting of disseminated tumor cells which foam thebasi.wfresiduldiseasainSCLC. TbecytotoxicpoteacyofSWAll- SPDBdg.rici” A chain was demonstrated in tissue culhtre by the inhibition of bH-leucine iacorporatio” md by the selective eliminntio” of CDU-positive htmor cells in clonogeaic assays. I” nude mice, SWAl 1-SPDBdg.ricin A chain w cleared from the blood circulation with biphpsic kinetics: pn initial a phase of 1 hr a”d a second 6 phase of 20.5 hr. Following i.v. injection of B dose equivalent to 30% of the LD,,theim”wm toxiadelsyedchegrowthofSW2mtid-hlmorxewgr.fts by 16days. ThethempeuticefficacyofSWAll-SPDBdg.ricinAchti was further demonstrated by the selective eliminstio” of clonogenic SW2 cells from smsll tumor-cell deposits established io sponge matrices. RegrowthofthcsolidtumorsaftertheinitinlresponscPndtheclonogenic activity in the sponge-derived cell population were mediated by CD24- positivecells. excluding the selection of CDZCoegative mutants during immunotoxin therapy.

Exprexsion of the pmta-oncogenes c-met and c-kit and their liiands, hepatocyte growth factor/scatter factor and stem cell factor, in SCLC cell lines and xenog&ts Rygaard K, NakmmwaT, Spmg-ThansenM. VnivlnsofPdwlogical Anatomy, Frederik V’s Vej Il. DK-2100 Copenhagen. Br I Cancer 1993;61:3146

we examined P panel of 25 snlall cell lung cancer (SCLC) cell Lies a”d nude mouge xenogrxfts for expression of the pmtc-oocogenes c-met and c-kit, a”d for expression of the correspc&mg ligsads, hepatocyte growth factor (HGF) (also Lnown as scatter factor (SF)), sod stem cell factor (SCF), respectively. Expnssio” of mRNA was d&cted by Northern blotting, ad C-U Md c-kit protein expression was detected by Western blottiag a”d immuoocytochemistry. c-met and c-kit mRNA was expressed in 22 of the examined cell Lies or xeaogmfts. and wexpressio” of the hvo pmto*“cngmea was observed in 20 hmmurs. Expression of c-me4 and c-kit pmtei” parallelled in the mRNA express- ion. HGFlSF mRNA was expressed in hvo of the examined hunours, a”d only me of these also expressed the c-met pmto-oncogene. SCF mRNAwrsexp& in 19oftheexamined htmours, and in 18 of these coexpressio” of c-kit Md SCF was present. The high percentage of SCLC tumours expressi”g c-m( a”d c-kit indicatea that these proto- oncogenea may have a” important function in this disease. The rare CoexpreggioD of c-w ;md HGFlSF is evidence that pn autacrine regulatory pathway is “ot p-t for this receptor/IigMd system i

SCLC. while the frequcat owxpmssio” of c-kit zmd SCF indicates that this recaptor/ligsnd system “uy have PO autowi”e function in SCLC.

Cytogenetic abnormalities in non-small cell lung carcinoma: Siiarity of findings in conventional and feeder cell layer cultures Siegfried JM, HtmtJD, Zhou J-Y, KellerSM, Testa JR. Depanmentof Phamurmlogy. Biomedical Science Tower, Pinsburgh Univ. S&o01 of Medidnr,Pins6urgh.PA1526I.Ga~s~~~~CPocerl993;6:30- 8.

Prinwy twnors from 39 patients with “o”-wnall cell bmg carcincma (NSCLC) weroexami”ed forcytogcllctic abnomulities by ccnventionnl short-term harvest (l-39 days) of primuy culh~res of minced solid- tumor tissues a”d by harvest of monolayer culturea of hlmor tissue (6 days to 5 months) O(I murine libroblast feeder layers. A successfid karyotype was obtied with both methodp in nine of 39 cases. Among the remnhig 30 cases, a successtid karyotype was obtpined io eight cases by the co”ventiooPl method only pnd in three cases by the feeder cell “lethod only. The success rates were 44% for the conventional method, snd 3 1% for the feeder cell method, md the combined success rate was 51% for one or the other method. The feeder culture method, i which harvests were usually performed at later times tha with the co”valtional “lethod. gmemlly produced “letaphases with superior banding, which allowed clearer definition of cytoge”etic aboormalities. I” addition, cell liars were estxblished in eight of these cases by the feeder cell method. Karyotypes from the longer-term harvests typically wereverysimilnrtothosefromshort-termco”v~tionnlcultures. Minor numerical differences md/or a few additional stmchwal abnormalities wennoted~sevenoftheniaecpses~ll~lyzedbybothmethods.Oversll. however, even in karyotypcs from 5-month cultures, the prominent rwwre”t chmges and modal chmmosome numbers observed in short- term cultures were still preset. The results indicate that long-term culture with tibmhlast feeder cells is a valid meens of obtaining cells from solid ltmg hmmrs for cytogenetic a”d molecular analysis. Cell lines established by this method will be useful in future molecular studies, forexemplc, formsppiogofchmmosome breakpoirttsand sites of chmmosome loss. for in situ hybrid&&m. and for &dies of the expressiooofcriticalcandidategenesimplicatedbycytogmeticfi”dings. In addition, by combination of conventional and feeder cell harvests. bothlbenumberofprim~ryhlmorssuccessfullyex~minedkPryotypically and the quality of the aaplyses are improved.

Cytokeratim expressed in experimental rat hmnchiil cawincmas Kal HB, Vpn Berkel AH, Brows JLV, Klein JC, Mijnheere EP, Roholl PJM et al. TN0 1n.u ApplitdRndiobiol. /bnmunol., I5I Lange Kleiweg, 2288 Gl Rijwijk. Int J Cancer 1993;53:506-13

Cytokerati” expression in rat lung hunors was studied using polypeptide-specific monoclonal antibodies (MAbs) to bumnn cytokemtins 4, 5, 7, 8. 10, 13, 14, 18 and 19. Experiments were performedwtumor~men(sderivedFromSexperimentnlratsqusmous- cell lung tumors md one adenocarciaomn, as well as on cell lines obtained from the same tllmors. The aims of this study were to investigate the differentiation profile of the rat htmor tissue and established humor cell lines based on light and electron microscopical features and on cytokerati” phenotype, to characterize the tumor type and degree of differentiation of the lung tllmors maintained during passaging in experimental animals, and to compare the cytokeralin expression patter” in tramplanted tumors with that of the cultures derived from these hmwrs. Our results indicate that, in general, the antibodies used cross-react with rat cytokemtins and that these MAbs CM be used to phenotype rat lung carcinomas. Both the tumor fragments andthefulturedcellsteveslednsimilnrpsttemofcytokerPtinexpression. In addition, thedegraeofdifferentiationwas maintained upon prolonged culturing in vitro. MAbs to cytokeratin sub-types CM therefore be used to distinguish the main sub-types of rat lung hunors and can give an indication about the degree. of differentiation.

Tumor-suppressive effect of the retinoic acid receptor I) in lmman epidennoid lung cancer cells Houle B, Rochette-Egly C, Bradley WEC. Jr&rut du Cancer de Montreal, ISWSherbrooke Ear, Montreal, Que. H2L 4MI. Proc Natl Acad Sci USA 1993;90:985-9

Retiooic acid receptor B (RARB), which codes for a nuclear receptor