Characterization of rabbit cytochrome P450IIC4 cDNA and induction by phenobarbital of related hepatic mRNA levels

We have cloned cDNA containing a partial sequence of a rabbit cytochrome P-450 (designated cytochrome P450IIC4) cDNA that is a member of the cytochrome P450IIC subfamily. The cDNA contains 770 bp of which the first 429 code for the C-terminal 143 amino acids of cytochrome P450IIC4. The protein coding region of the cDNA is 98% homologous with that of cytochrome P450IIC5 and the 3' untranslated region is about 90% homologous. In contrast to the constitutive isozyme, cytochrome P450IIC5, mRNA in the liver that hybridized to the 3' untranslated region of cytochrome P450IIC4 cDNA was increased about 8-fold 24 hours after a single injection of phenobarbital.

Cosmid vectors for rapid genomic walking, restriction mapping, and gene transfer

We have designed cosmid vectors for rapid genomic "walking" and restriction mapping. These vectors contain the transcription promoters from either bacteriophage SP6, T7, or T3 flanking a unique BamHI cloning site. Mammalian expression modules encoding the dominant marker neomycin phosphotransferase or the amplifiable dihydrofolate reductase gene expressed from SV40 promoters were inserted for use in gene transfer studies. Restriction sites for the enzymes Not I and Sfi I, which cut mammalian DNA very infrequently, have been engineered near the transcriptional promoters to enable the excision of most inserts as single, full-length fragments. Genomic libraries representative of mouse, human, and hamster genomes were constructed by inserting 33- to 44-kilobase-pair (kbp) DNA fragments, generated by partial cleavage of genomic DNA with Mbo I or Sau3A, into the unique BamHI site. Digestion of recombinant cosmids with restriction enzymes that cleave frequently but do not disrupt the transcriptional promoters generates two small DNA templates for the synthesis of end-specific RNA probes to facilitate directional "walking." Cosmid restriction maps can be determined rapidly by one of several methods. The cosmids and methods we describe should have wide utility in determining the functional and structural organization of complex eukaryotic genomes and for physically linking distant genetic loci.

[Cisplatin or combined cisplatin and 60Co radiation in the treatment of advanced lung cancer--report of 145 cases]

The result of 145 patients with advanced primary lung cancer treated by cisplatin alone or combined cisplatin and 60Co radiation from June 1981 to August 1983 is reported. 75 of these cases were clinical stage III and 70 stage IV. 57 (39%) were proved by pathology and 64 (44%) by cytology, totalling 121 (83%) as non-small cell lung cancers. The other 24 (17%) were diagnosed by clinical means. All the patients were divided into two groups. Group I, 26 cases were treated by cisplatin alone. In this group, no complete response was found, the partial response rate was 31% and 1-year survival rate was 40%. Group II, 119 patients were treated by the combination of cisplatin and 60Co radiation. Complete response rate was 16%, partial 59%, 1 and 2-year survival rates were 52% and 33%, respectively. The results show that the combination of cisplatin and 60Co therapy is more effective for the advanced lung cancers.