Abstracts/Lung Cancer 10 (1993) 123-150 129

mutation frequency (46%) of the p53 gene in tumors carrying mutated ras genes was essentially the same as the ovetnll freqllellcy in lung cancers, suggesting that accomulation of mutations in these hvo genes in P honor is a random phenomeaon.

K-ras activation in nowmall cell lmtg cancer in th dog Kraegel SA, Gumerhck PH. Dungworth DL. Greffo VIC. Madewell BR. Depanmenr of Surgery, School of Vemimry Medicin, Uniwrsiry of California, Davis, CA 956168745. Cancer Res 1992;52:4724-7.

To investigate the role of K-M mutations in canine non-smell cell long cancer, we first determined the nocleotide sequence of the normal canine K- M gene and then examined 21 caoine lung tomors for activating K-as mutations. Canine K-ras was pnplyzed by direct sequencing of polymerpse chaii reaction pmdocts gmemted with oligonucleotide primers derived from the human K-ras sequence. Four nucleotide differences were found bdweea the canine and human K-ras sequence from position 5 to 211. The deduced amino acid sequence of the canine gene. was identical to that of the human. Activated K-ras alleles were detected in 5 of the 21 caoine long tumors examined. Tbe activating lesionswerepoint mutations. pmdominaotly inwdon 12. Of the 14 adenocarcinomas examined. 2 (14%) had K-ras mutations. Two of5(40%)~m~~mouscDnrinorms~dIheoalyI~geceUcorciaoma also contained activated alleles. The overall frequency of K-res point mutation in non-smell cell long cancer (2.5 %) is similar to that reported in human non- small cell long cancer. We conclude that K-w activation by point mutation is associated with, but not necessary for, non-smell cell lung cancer development in the dog.

ActivationoftheKi-rasgeneinspontaneousandehenicallyindueed lung tumors in CD-I mice Manam S, Storer RD, Prahalada S, L.eaoder KR. Kraynak AR, Hammermeister CL et al. Depatimmt of Safety Awessment. Merck Sharp and Dohme Researd Labs.. West Point. PA 19486. Mel Carcinog 1992;6:68-75.

As part of no evaluation of the effectiveness of using ras mutation aMlysisfordistinguishingcarcinogeo-inducedfromspontrmeoustumors, we examined the profile of ras gene point mutations in spontaneous, 7,12-dimethylbenx[a]anthracene (DMBA)-induced, and N- nitrosodiethylamine@EN)-inducedluagtumorsfromCrl:CD-l(ICR)BR (CD-I) mice. Although all of the long tumors were assayed for mutations in the Ha-ras, Ki-ras, and N-w genes @dons 12, 13, and 61). only Ki-ras mutations were found, which is consistent witb other studies that have noted a strong preference for Ki-ras gene activation in mouse, rat, and human lung tumors. We found that spontaneous CD-I mouse lung tomors bad a very high frequency of Ki-ms gene activation (17 of 20 hnnors; 85 %), cbstributed among codons 12 (5 of 20), 13 (1 of 20). and 61 (11 of 20). DMBA-induced long honors had a slightly higher frequency of KI-ms gene mot&mm (16 of 16; lOO%). again distributed among codons 12 (5 of 16), 13 (2 of 16), end 61 (9 of 16). However, seven of the DMBA tumors had mutations qualitatively difterent from those found in spontaneous tumors. In contrast to DMBA-inducedhonors, DEN-inducedtumorshadelowerfrequencyof KI-ras mutations (36 46) whea compared with spontaneous lung honors, suggesting that DEN primarily Induces long carcinogenesis by a mechanism other than ras gene activation. Thus. although spontaneous and induced CD-1 moose lung tomors have P strong tissue-specific preference for carrying an activated Ki-ras gene, the nahue of the initiating carcinogen can influence the frequency or profile of Ki-ras mutations.

Chanctaization of the submiawcopic deletion in the small-cell lung carci- (SCLC) cell line UzozO DrPMrinHA,MendezM1,R~~ttsPH,Vsllta?yT,&rghJ,Schlessinger J et al. Division of Medical Oncology, Uniwrsity of Colorado Cancer Cenrer, 4200 E. 9th Aw., Denver. CO 80262. Genes Chromosomes Cancer 1992;5:67-74.

The smallsell long carcinoma cell line U2020 contains a submicroscopic, homozygous deletion that removes a chromosome1

segment within 3p13-~14. including the locus D3S3. We have

subloc&zed 49 additional probes to the 3~13~14.2 @ion nod have

identified 7 new DNA markem that arise from within the U2020 deleticm. The estimated sir+ of the deletion, based on marker deasity, is approximately 4-S megabws (Mb). Inchdiig D3S3. 7 of the 8 merkersbavebeen linkedbypulsed-fieldgel (PFG)electmpboresisover anareaofapproximetiy2Mb. Inclodingtheoneunliieduwker, PFG analysis accounts for about 3 Mb of the region. The U2020 deletion appears confined to the 3~13~14.2 region and does not include the candidate tumor suppressor gene, protein-tyrosine phosphatase gamma (PTPG).

Exptwion of EGF, TGF-a and EGEa in squamous cell lung rarciwmss Gorgoulis V. Aninos D, Mikou P, Kanavuos P, Kanmeris A, Jaudanoglou J et al. 1n.w Biolq. Researcfi Biorecimology. National Helknic Rsrch Foundation, 48 Var Commn~inou Ave. 116 35 Arhem.

Anticancer Res 1992; 12: 1183-7. Immonohistochemical study of epidermal growth factor (EGF),

epidenmd gmwth Hector receptor (BGFR) end transforming growth factor-a (TGF-a) expression was pe&rmed on ppnffinzmbedded tissue specimens of 70 squamous cell lung carcinomep. The carcinomas wereplaced tooneofthefollowingeightgmops, according totberesults of EGF, TGF-a and EGFR expression: group 1: none, group 2: only EGFR. group 3: EGFR and TGF-a, group 4: EGFR nod EGF, group 5: TGFaendEGF.group6: aUthree,groop7:onlyTGF-aandtinrdly group 8: only EGF. Statistical analysis of the results revealed that the ratio of aquamow cell lung carcinomas with lymph node maestasis was significantly higher in groups 4,s end 6 (P< 0.01). We also examined whether EGF receptors were tnmcated with the we of two monoclonal antibodies directed against differat portions of the receptor (EGFRI and F4). No truncated EGF rece@ors were detected. These results suggest that lung carcinomas expressing the molecules EGFIEGFR, TFG-alEGFR or TGF/a/EGF/EGFR display pathologic featores of more aggressive disease.

UDP-N-acetylhexosamine modulation by gluwsam he and midine in NC1 N-417 variant small cell lung cancw cells: IlP nuclear magnetic resomlnce results Pederson NV, KnopRH, Miller WM. CbmicalEngineeringLIqamnenepomnenr, Northwestern University, Evanston, IL 60208-3120. Cancer Rex 1992;52:3782-6.

Smnllcelllungcancer(SCLC)occursashvoow~docrinesubtypes, SCLC- C (classic) and SCLC-V (variant). One repotted difference is elevated levels of dipbosphodiesters (DPDE) in the more diffenmtiated SCLC-C subtype. DPDE have been identified as primarily UDP-N- acetylhexosamines (UDP-NAH) in a variety of tumors, and chaoges in DPDE levels have beea observed during experiments designed to induce cell differentiation. UDP-NAH synthesis is controlled by negative feedback regulation of glutamine:f~ctose-6-P amidotransferase (EC 2.6.1.16). which can be circumvented by glucosamine. Using “P nuclear magnetic resonance analysis of extra&s end perfused cells, we have identified UDP-N-acetylglocosamineand UDP-N-acetylgalactos- amineas the primary metabolites in the DPDE spectral region of SCLC- V N-417 cells. Glucosemine addition causes P rapid increase in UDP- NAH levels. At glucosamine: glucose ratios of 1: 1 and 10: 1 formation of the UDP- NAH intermediates N-acetylglucosamine 6-phosphate and UDP-N-acetylglucosamine l-phosphate is also observed, indicating UTP limitation. Subsequent uridiie addition results in depletion of the intermediates and increased UDP-NAH formation. Moreover, N-417 cells retain the capacity to rapidly convert uridine to UTP despite low ATP and pbospbocreatine levels. This expansion of tbe uridine pool may represent an additional metabolic reserve not yet addressed in the design of therapy options.

Ras oncogene point mutation: An infrequent event in brmwhioloalveolar- Rwh VW, Rater VE, Kris MG, Kurie J, Miller WH Jr., Nanus DM etel. l7wracicSwgerySewice. MrmorialSloan-Kcnrr CaneerCR., 1275 York. Aw., New York, NY 10021. J Thorac Cardiovpsc Sorg 1992:104:1465-9.