82

or in aiding adults to quit smoking. To be

most effective and convincing in combating the smoking epidemic, practicing physicians

must have the same basic fund of knowled- ge about the short- and long-term consequen- ces of smoking as they do about other com- monly encountered medical problems. By acting on such knowledge and adopting a definite set of attitudes and activities in their offices and with patients, physicians can make a significant contribution to their patients and to the entire community in which they practice.

3, BASIC BIOLOGY

Histocompatibility Antigens in Small Cell Carcinoma of the Lung. Markman, M., Braine, H.G., Abeloff, M.D. The Johns Hopkins Oncology Center, The Johns Hopkins University School of Medicine, Baltimore, MD, U.S.A. Cancer 54: 2943-2945, 1984.

Fifty white patients with small cell carcinoma of the lung (SCCL) were typed

for histocompatibility antigens (HLA) to assist in providing platelet support for intensive induction therapy. An analysis of the HLA types in this population was undertaken to determine if there was an in- fluence of HLA type on this disease. Pa- tients with the HLA-Bw44 (HLA-BI2) allele were found to be significantly overrepre- sented in our patient population compared to a control population (52% versus 26%, p < 0.001). In addition, patients posses- sing the HLA-AI phenotype were found to have a significantly poorer 1-year sur-

vival rate (15%) than individuals who did not possess this allele (60% 1-year survival rate) (p < 0.025). These findings will need to be confirmed by other groups working with large numbers of patients with SCCL.

~hltipotential Behaviour of Cloned Rat Mesothelioma Cells with Epithelial Pheno- type. Brown, D.G., Johnson, N.F., Wagner, M.M.F. MRC Pneumoconiosis Unit, Llandough Hospital,

Penarth, UK. Br. J. Cancer 51: 245-252, 1985.

Reference cultures derived from a trans- plantable rat mesothelioma were obtained

by cloning cells three times in soft agar. Each line, designated "Carm-Lines", was selected on the basis of their epithelial or fibroblastic phenotype, and their uni- form morphology. Three epithelial lines were used for more detailed in vitro stu-

dies comparing morphological and biologi- cal criteria at early and late passages. All three lines exhibited both epithelial

and fibroblastic elements after 10-14 pas-

sages in vitro, demonstrating that the

dimorphic histology of these tumours could be derived from a single aberrant cell. Morphology

and growth characteristics of these cells were density-dependent. Anchorage dependent and in-

dependent clonogenic assays did not correlate. Anchorage dependent colony formation was the only parameter which differed markedly from the original parent line in the assays descri- bed. In vivo evidence of chondrogenesis and attempted ossification support the concept of a multipotential cell contributing to the di- verse primary tumour morphology by cellular mo- dulation or differentiation.

Trisomy 7 in a Lung Carcinoid Tumor: Precocious Index of ~lignant Transformation? Teyssier, J.R., Sadrin, R., Nou, J.-M., et al. Laboratory of Histology, Embryology, and Cyto- genetics, Medical School, University Hospital,

51100 Reims, France. Cancer Genet. Cytogenet. 15: 277-282, 1985.

A chromosomal study has been performed on a benign carcinoid tumor of the lung after short- term culture. A trisomy of chromosome = 7 was found in all the metaphases. The significance of this findings is discussed in relation to the transformation process.

Transformation of HL~an Bronchial Epithelial Cells Transfected by Harvey Ras Oncogene. Yoakum, G.H., Lechner, J.F., Gabrielson, E.W.',

et al. Laboratory of Human Carcinogenesis, Na- tional Cancer Institute, Bethesda, MD 20205, U.S.A. Science 227: 1174-1179, 1985.

Transfection of normal human bronchial epi- thelial (NHBE) cells with a plasmid carrying the ras oncogene of Harvey murine sarcoma virus (v-Ha ras) changed the growth requirements, terminal differentiation, and tumorigenicity of

the recipient cells. One of the cell lines iso- lated after transfection (TBE-I) was studied extensively and shown to contain v-Ha ras DNA.

Total cellular TNA from TBE-I cells hybridized to v-Ha ras structural gene fragment probes fi- ve to eight times more than RNA from parental NHBE cells. The TBE-I cells expressed phospho- rylated v-Ha ras polypeptide p21, showed a re-

duced requirement for growth-factor supplementsj and became aneuploid as an early cellular rem sponse to v-Ha ras expression. As the trans-

fectants acquire an indefinite life-span and anchorage independence they became transplan- table tumor cells and showed many phenotypic changes suggesting a pleiotropic mechanism for the role of Ha ras in human carcinogenesis.

Biochemical Measure of the Volt~e Doubling Time of Human Pulmonary Neoplasms. Greengard, O., Head, J.F., Goldberg, S.L., Kirschner, P.A., Mount Sinai Medical Center, Department of Pediatrics, New York, NY 10029, U.S.A. Cancer 55: 1530-1535, 1985.

The volume doubling time (DT) of human lung neoplasms, determined from sequential, presur-

gery roentgenograms, was compared'with bioche-