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Human lung cancer nodules in organotypic culture: No evidence of correlation between the antiproliferative effects of interferons and the induction of 2’, 5’-oligoadenylate synthetase. Martyre M-C, Beaupain R, Falcoff E. U 196 INSERM, Instirul Curie, F- 75231 Paris Cedex 05. Tumor Biol 1988;9:263-9.

Alveolar II pulmonary tumor cells (A549). maintained in continuous tridimensional organotypic culture, were used in an attempt to investi- gate whether there could be a relationship of the 2’,5’-oligioadenylate (2,5A) synthetasepathway totheantipmliferativeactivity ofinterfemns (IFNs) in this particular tumor cell model. IFN-,, -8 and -gamma were used separately and in combinations. IFN-, and -gamma demonstrated an inhibitory effect on the nodule growth, whereas lFN-8 did not. Moreover, combinations of IFN-_, and -gamma resulted in a significant synergisticamiproliferative activity; IFN-Bonlypotentiatedslightly the effect of IFN-gamma. All three IFNs induced an increase in the 2,5A synthetase activity, indicating a discrepancy with the pattern of anticel- lular activity. Furthermore, whereas the combination of IFN_, and - gamma resulted in a synergistic antiproliferative effect, no synergism was observed in the induction of the enzyme. These results show that there is a lack of correlation between the sensitivity or the resistance to IFNs of A549 tumor nodules and the induction of the 2,5A synthetase activity.

Transferrio synthesis by small cell lung cancer cells acts as an autocrine regulator of cellular proliferation. Vostrejs M, Moran PL, Seligman PA. Division of Hematology. Univer- siry of Coloraab Health Sciences Center, Denver. CO 80262. J Clin Invest 1988;82:331-9.

Since transfertin is required for cellular proliferation, we investigated transferrin synthesis by a small cell lung cancer line (NCI-H5 10) that survives in serum-free media without added transferrin. Immunoassays for human transferrin demonstrated that these cells contained im- munoreactive human transferrin. Immunofluorescence studies showed that the protein is expressed on the surface of cells, presumably bound to transferrin receptor. Media conditioned by NCI-H510 cells support proliferation of human leukemic cells that would not survive in media lacking transferrin. [rsS]Methionine incorporation documented tram- ferrin synthesis by NCI-H5 10 cells as well as three other small cell lines. Transferrin synthesis by NCI-H510 cells increased more than IO-fold when cells entered active phases of the cell cycle, and this increase was seen before large increases in transfertin-receptor expression. Further experiments examining the effects of agents that affect iron metabolism show that the addition of agents that affect iron metabolism show that the addition of transferrin-iron or hemin to the media is associated with a more rapid initial rate of proliferation and lower rates of trausfenin synthesis than control cells. Gallium salts, which inhibit iron uprake, inhibited proliferation of these cells. If the cells recovered from this effect, transferrin synthesis remained greatly increased compared to control. We conclude that transferrin synthesis by these malignant cells is ultimately related to an iron requirement for cellular proliferation. It appears that this synthesized transferrin acts as part of an important autocrine mechanism permitting proliferation of these cells, and per- haps permitting tumor cell growth in vivo in areas not well vascularizd.

Insulin-like growth factor-1 can mediate autocrine proliferation of human small lung cancer cell lines in vitro. NakanishiY,MulshineJL,KasprzykPG,NataleRB,ManeckjeeR,Avis 1, Treston AM, Gazdar AF, Minna JD, Cut&a F. National Cancer Institute-Navy Medical Oncology Branch, Division of Cancer Treat- meal, Befhesda. MD 20814. J Clin Invest 1988;82:354-9.

The effect of insulin-like growth factor I (IGF-I) on growth of small cell lung cancer (SCLC) cell lines was studied. Western blot analysis of whole cell lysates of cell lines NCIH345 and NCIN417 demonstrated the presence of a 16-kD band consistent with an IGF-I precursor molecule. Scatchard plot analysis of cell line NCI-H345 using l”I- labeled IGF-I demonstrated two high affinity specific binding sites (K(d) 1.3 and4.0nM with maximal rate(B(max))200arid 5OOfmol/mg protein, respectively). The exogenous addition of IGF-I, IGF-II, or insulin resulted in marked proliferation of human SCLC cells as evaluated using an in vitro growth assay. These peptides stimulate the

growth of SCLC cell lines NCI-H82, NCI-H209, NCI-H345, and NCI- N417. The concentration of IGF-I producing maximal SCLC cell growth was IO- lfkl-fold less than that of insulin or IGF-II, whereas the maximal growth stimulated by the optimal concentration of these peptides were similar. An MAb that specifically binds to the IGF-I receptor (but not to the insulin receptor) mediates a dose-dependent inhibition of cell growth in basal media as well as IGF-I, IGF-II, or insulin-supplemented media. The IGF-I receptor thus appears to be the common pathway for the mitogenic activity by IGF-I, IGF-II, and insulin for human SCLC cell lines. The demonstration of an IGF-I precursor molecule, specific IGF-I receptor binding, IGF-I-mediated growth stimulation,andinhibitionofbasalcellgrowth by an MAbtothe IGF-Ireceptorsuggeststhatan IGF-I-IikemolecuIecan function in vitro as an autocrine growth factor for human SCLC cell lines.

A23187 and protein khtase C activators stimulate phosphatidylino- sitol metabolism and prostaglandin synthesis in a human lung cancer cell line. Rapuano BE,BockmanRS.DivisionofEndocrinology. CornellUniver- sity Medical College, Hospital for Special Surgery, New York, NY 10021. Biocbem Biophys Res Commun 1988;156:644-52.

Activation of cell phospholipase, release of arachidonic acid and stimulationofprostaglandin synthesis werestudiedin anewlydescribed human tumor cell line (Lu-65). In the Lu-65 tumor cell line, thecalcium ionophore A23 187 (2 *M) caused a 100% increase in the release of ‘H- aracbidonic acid and a ‘I-fold increase in the synthesis of prostaglandin ET 1-oleoyl, -Zacetyl-glycerol (IOU .M) increased arachidonate re- lease and prostaglandin E, synthesis by 100%. A23187 and the protein kinase C activators, 1,2-dioctanoyl-glycerol and I-oleoyl,-2-acetyl- glycerol, decreased the specific radioactivity of ‘H-arachidonate in phosphatidylinositol by 37% and 57%. respectively. The effects of A23187 were blocked in Caz+-free media or in the presence of the phospholipase A, inhibitor, p-bromophenacyl bromide, while those of I-oleoyl,-2-acetyl-glycerol were not. The data provide evidence in a human tumor cell line for calcium/phospholipase AZ-dependent and independent pathways for aracbidonic acid release, both of which preferentially hydrolyze phosphatidylinositol.

Oncogene expression detected by in situ hybridization in human primary lung cancer. Lee JH, Lee DH, Park SS, Seok SE, Lee JD. Deparrment of Medicine, Hanyang University School of Medicine, Seoul. Chest 1988;94: 10469.

By means of in situ hybridization using biotinylated oncogene probes and the immunohistochemical reaction of avidin-biotin complex-alka- line phosphatase with substrate, we investigated expresson of c-myc oncogeneinthefonnalin-fixed,pmaffin-embeddedtissuesectionsfrom seven patients with squamous cell carcinoma (six cases) and small cell carcinoma (one case) of primary lung origin. The expression of c-myc oncogene was greatly enhanced in all cases studied., with individual and cell-to-cell variation. In contrast, all of the specimens incubated with deoxyribonucleaseafterthe standardpretreatmentwithribonucleaseT1 were negative for the expression of c-myc oncogene. The in situ hybridization permits estimation of a heterogeneous amplification of c- myc oncogene that may be related to secondary alterations occurring during the progression of the malignant lung tumors.

myc Family gene abnormality in lung cancers and its relation to xenotransplantability. Gemma A, NakajimaT, Shiraishi Met al.PathologyDivision. Narional Cancer Center Research Insritute, Chuo-ku, Tokyo 104. Cancer Res 1988;48:6025-8.

In order to study the relationship between tumor transplantability to the nude mouse and abnormality of the myc family genes (c-my& N- myc, L-myc) in human primary lung cancers, 32 various lung cancers wereanalyzedforabnormalityofthemycfamilygenesby Southemblot hybridization, and were transplanted S.C. into nude mice. Southern blot analysisshowedthatfournon-smallcellcarcinomasandthreesmall~ll carcinomashadampIifiedc-mycandL-mycgenes,respectively.Allelic deletion of the L-myc gene was observed in seven cancers, of which two