Cancer Epidemiology and the Cell: From a Micro to Macro View

The epidemiology of many cancer sites differs substantially when cell type is considered. One only need to look at recent trends in esophageal cancer incidence, which vary by histology (squamous cell esophageal cancers and adenocarcinomas show differences by race and geographic location). These may have different etiologies and survival as well. Cell specific differences are well known in lung cancer, skin cancer, cervical cancer, breast cancer, colon, kidney and others.

With completion of the human genome project and ever improving biotechnology, cellular and molecular processes and markers have been sought to explain differences in the epidemiology of cancers among different populations. These investigations have typically focused attention on early markers of exposure, early markers of transformation, impaired repair mechanisms, mutations-whether heritable or not, telomere length, cell cycle control and others. Most of these efforts have been in the quest of trying to identify or explain mechanisms of cancer, or precancer occurrence. While substantial attention has been focused on treatment response and effectiveness for cancers of specific cell types, considerably less attention has focused on how subcellular properties are related to survival.

Unfortunately, too many studies have produced results that are difficult to interpret, either because they have come from small studies and made multiple comparisons. Other studies because they have not been able to be replicated. Larger studies, often the result of pooled specimens, have identified differences- e.g., aberrant genotypes, which are associated with very specific cancers. With few exceptions, such findings only explain a small percentage of cancers of any particular type. Regardless, we have seen an explosive emergence of “omics” data; genomics, metabolomics, exposomics, transcriptomics, proteomics and bioinformatics.

Their results from these varied studies are still valuable, because they offer clues for further investigation, and have fostered communication between disciplines that use very different terminology, techniques, and languages. Epidemiologists have gained insight into mechanistic issues, and bench scientists have developed a more population-based perspective.

Perhaps unfortunately, biotechnological developments have driven some of the investigations, rather than vice versa. Epidemiologists have frequently jumped into the technology at the expense of keeping basic principles of epidemiologic design and analysis in the forefront. The challenge is for the field of molecular epidemiology to untangle the complex unresolved cancer issues utilizing the various “omics” to translate the research findings into improved population outcomes.

Furthermore, analogous to the biostatistical software which produces results for investigators who may not understand what is happening “behind the curtain”; biotechnological advances produce results for individuals who may be clueless as to what is happening. At least some members of any research team should understand underlying assumptions, and the limitations associated with the output. Whether using biostatistical software or biotechnological techniques.

With this in mind, Epidemiology: Open Access (https://www.omicsonline.org) is preparing a special issue on Cancer Cell Epidemiology, and are inviting researchers to submit manuscripts dealing with any of cancer issues. Epidemiology: Open Access is the logical place for such research, i.e., at the crossroads of cancer epidemiology and biotechnology. Studies focusing on cellular and subcellular characteristics within epidemiologic studies are highly encouraged.