Understanding how health care system structures, processes, and available resources facilitate and/or hinder the delivery of quality cancer care is imperative, especially given the rapidly changing health care landscape. The emerging field of cancer care delivery research (CCDR) focuses on how organizational structures and processes, care delivery models, financing and reimbursement, health technologies, and health care provider and patient knowledge, attitudes, and behaviors influence cancer care quality, cost, and access and ultimately the health outcomes and well-being of patients and survivors. In this article, we describe attributes of CCDR, present examples of studies that illustrate those attributes, and discuss the potential impact of CCDR in addressing disparities in care. We conclude by emphasizing the need for collaborative research that links academic and community-based settings and serves simultaneously to accelerate the translation of CCDR results into practice. The National Cancer Institute recently launched its Community Oncology Research Program, which includes a focus on this area of research.

The inducible quinic acid catabolic pathway of Neurospora crassa is controlled by four genes, the qa cluster which includes structural genes qa-2, qa-3, qa-4 for three enzymes and a regulatory gene, qa-i. In this pap r we report the molecular cloning of at least the qa-2 gene which encodes the catabolic dehydroquinase (5-dehydroquinate hydro-lyase, EC 4.2.1.10). Endo-R-HindIII restriction endonuclease fragments of N. crassa DNA from a qa-i C (constitutive) mutant and of Fscherichia coli plasmid pBR322 DNA were ligated in vitro and used to transform an aroD6 (5-dehydroquinate hydrolyase deficient) strain of E. coli K12. The recombinant plasmid (pVK55) isolated from one AroD+ transformant (SK1518) contained, in addition to pBR322, two N. crassa HindIII fragments with molecular weights of 2.3 X 106 and 1.9 X 106. Derivatives of SK1518 cured of plasmid DNA were phenotypically Amps and AroD-. These cured strains, retransformed with pVK55, were phenotypically Amp" and AroD+. Strains transformed with pVK5S possessed 5-dehydroquinate hydrolyase activity but no activity was-present in any AroDW strain. The enzyme extracted from strains containing the recombinant plasmid-was identical to N. crassa catabolic dehydroquinase by the criteria of heat stability, ammonium sul ate ractionation, immunological crossreactivity, molecular weight, and purification characteristics. This identity demonstrates that the N. crassa qa-2+ gene is carried by the recombinant plasmid and is apparently transcribed anytranslated with complete fidelity. Furthermore, subunit assembly of the N. crassa polypeptides also occurs in E. coli, because the catabolic dehydroquinase is a multimer composed of approximately 20 identicalsubunits.Recent progress in the elucidation of molecular mechanisms involved in genetic regulation in prokaryotes has depended on the isolation of DNA sequences carrying both structural and regulatory genes. Purification of these DNA sequences has led to the establishment of in vitro systems in which the mode of action of regulatory proteins could be directly tested (1) and, in addition, has permitted the sequencing of promotor and operator regions (2-4). By using molecular cloning techniques, it should now be possible to isolate similar DNA sequences from eukaryotes. Of particular significance is the recent demonstration by Struhl et al. (5) and Ratzkin and Carbon (6) that either X or plasmid hybrids containing specific yeast genes can be selected by their ability to complement auxotrophic mutants of Escherichia coli. Cloned DNA sequences obtained by this method will be useful for the study of eukaryotic gene regulation only if they contain both structural and regulatory genes.One such DNA sequence is the qa gene cluster of Neurospora crassa which controls the first three reactions in the inducible quinic acid catabolic pathway (Fig. 1A) (7,8). Three of the loci are the structural genes for the individual qa enzymes: qa-2, catabolic dehydroquinase (5-dehydroquinate hydro-lyase, EC 4.2.1.10); qa-3, quinate dehydrogenase...

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