071

Competent and Affecting GRP

of Small Cell Lung _-- M.Shlwa. H.Kamma.

Priming Activities and IGF-I in Pro1 iferation --- Cancer Cell lines ~- H.Horiguchi, and T.Ogata.

Dept. of Pathology, University of Tsukuba, Tsukuba. Japan.

Growth factors have been be1 ieved to be divided in three groups: competence. priming and progressi on factors. GRP and IGF-I are progression factors promoting the growth of small cell lung cancer. We studied the influence of POGF and EGF as competent and priming factors. on the growth enhancement of GRP and IGF-I in three small cell cancer cell lines: TKB-lZ(classic type), TKB-2(variant type) and TKB-15(i ntermediate type). Growth enhancements of each factors and their combination were assayed using BrdU and MTT. The results are indicated below.

TKB-12 TKB-15 TKB-2

GRP GRP + PDGF GRP + EGF 1

[ ;

IGF-I IGF-I + PDGF IGF-I + EGF il il

1 tt

PDGF or EGF promoted the growth enhancement of GRP and IGF-I. depending on the cell types of small ccl 1 cancers.

073

Frequency of point mutational activation of the Kras oncogene in non-small ccl 1 1 ung cancer in ..- .- qng Kong **

M Lunq , M Wonq , WK Lam***, KS Lau+, S Kwan+, KH FU@, i Cheung “, -WW Yew+ Depts of Microbiology*, Pathology**, Medicine*** & Surgery++, HK University, Queen Mar Hospital; TB & Chest Unit+ & Dept of

@y Pathology , Grantham Hospital, Hong Kong. In Hong Kong, lung cancer is the commonest

lethal malignant disease in both sexes. In women, its mortality rate ranks amongst the highest in the world, with a preponderance of adenocarcinoma (AD) and non-smokers. We investigated the frequency of point mutational activation of K-m codon 12 in lung cancer by PCR and DNA dot blot analysis using mutation-specific oligonucleotide probes. Totally, 52 frozen tumour specimens obtained at thoracotomy and 80 formalin-fixed paraffin-embedded tumour samples were studied. Of these, 63 were squamous cell cancer (SQ), (men 58/63) and 63 were AD (men 32/63). Seven tumours (all men, 6AD, lSQ, l/7 non-smoker) were positive for a point mutation in K-m codon 12 (6/63 or 9.5% for AD, l/63 or 1.6% for SQ). The normal DNA sequence GGT at codon 12 was altered to IGT in 4 tumours (3AD, lSQ), to GAT in 2 (AD), and to AGT in 1 (AD).

Our study confirmed the increased frequency of K-ras codon 12 point mutation in AD, but this mumon is not significantly linked to AD among females in Hong Kong (O/31). Additional oncogenes, anti-oncogenes and genetic factors need to be studied in our female patients.

072

21

Sensitivity to etoposide (VP%) and expression of DNA- topoisomerase 11 (TII) in small ceII lung cancer ceII lines. Jane A Plumb, WN Keith, SR Bicknell, R Milroy and SB

Kaye. CRC Dept of Medical Oncology, University of Glasgow, Glasgow G12 8QQ, Scotland.

In an attempt to identify possible mechanisms of drug resistance in small cell lung cancer (SCLC) we have established 8 SCLC ceil lines from individual patients. The lines show a 60 fold range in sensitivity to doxorubicin (DOX) and to VP16 but p-glycoprotein (P170) is completely absent. To explore alternative mechanisms we have measured levels of TIIa in 7 of these lines by western blot. Three cell lines had high levels and were sensitive to VP16 (ID,, m ;LS106 0.8, LS112S 0.6, LS277 0.1). One cell line had low levels of TIla and was resistant to VP16 (LSlll 4.8). Of the 3 cell lines with intermediate levels of TIla, one was sensitive to VI’16 (LS263 0.5) and the other two were resistant (LS274 3.3, LS310 10.0).

We have derived two DOX resistant sub-lines from LS112S. LS112D1.8 is resistant to DOX (13 fold) and VP16 (21 fold), does not express P170 but shows a marked decrease in the level of TIIa. LS112D7.2 was derived from LS112D1.8 by further exposure to DOX. This line also shows decreased TII a expression but in addition expresses P170.

For the SCLC cell lines expression of TIla appears to correlate with sensitivity to an inhibitor of the enzyme. Induction of drug resistance resulted in changes in TII a activity before expression of P170 was induced. This suggests that drug resistance in SCLC could be due to altered activity of TII.

074

SPECIFIC CYTOLYTIC T CELL CLONES FOR AN AUTOLOGOUS SMALL CELL LUNG CANCER (SCLC) CELL LINE. P. Weynants (I), P.G. Cculie (2). Ph. Hamaut (2). M. Scmville (2). Th Boca (2) (1) Universiti Catholiqoe de Lwvain. Monl-Gcdmoe Hosptal. Service de Pneumolog~e, 5530 Yvor, Belgmm (2) Ludwig Institute for Cancer Research. Bmssels Branch, 7459 wenoe H,ppwate, 1200 Bmssels. Belgum

We and others have described m ntro cytolyuc T cell (CTL) clcnes showing specificity for various types of autologous human tomon (1). However to our knowledge. IX) CI’L clones for aotiogoos SCLC cell line have beer, reported so far. We have prewmsly shown lhat q’tolytic actin~y mediated by CDS+ lymphocyle can be obmmed agmnst allogcneic SCLC cell Lines upon mixed lymphwpc tumor cuhore (MLTC) ooly provided that SCLC targets were pretreated wnh Iowferon gamma (IFNUy) in order 10 increase their expresaoo of MHC class I mobxules

(2). In cur present study, we tied to cbmio specif,c CTL response by somulating pcnphernl blood mononuclear celh (PBMC) of par&m “Vase” wth its autologous SCLC cell hoe derived frcm mems~lnc mediastiotinal lymph nades. We failed to ok&, any qxcific CTL nspcn% However. using purified CDg+ lymphocytea instead of PBMC as responder cells. we succeeded m dentig CTL lhsr lyzed Imerferm treati aotologoos Vase SCLC cell line. No significant lysls was observed on the NK targd K562, the LAK target Daudl, or allogeneic SCLC target OCI even pret,eated w,,h IFN~ Fmally. we claned those CTL by limmng dilution and derived 5 stable CTL clooes that showed Ihe same specific,ty for the aotologow SCLC cells including absence of lync activxy for autologoos blast lymphocytes.

1) M. Hem,, C. Lrmome. P. Weyoaou et al. Production of stable cy?olytic T cell clones derived against autdcgous human melanoma. Ior. 3. Cancer 1987; 39 : 390-396. 2) P. Weyowts, P. Waoters, P. Co&e u al. Cymlylic T cell against allogeoe~c smell cell caocer treated wrlh gs,moa lme,fem,,. Cancer Jmmunol. Immonoth. 1988; 27 228.232.