Genomic and oncoproteomic advances in detection and treatment of colorectal cancer

<p>Abstract</p> <p>Aims</p> <p>We will examine the latest advances in genomic and proteomic laboratory technology. Through an extensive literature review we aim to critically appraise those studies which have utilized these latest technologies and ascertain their potential to identify clinically useful biomarkers.</p> <p>Methods</p> <p>An extensive review of the literature was carried out in both online medical journals and through the Royal College of Surgeons in Ireland library.</p> <p>Results</p> <p>Laboratory technology has advanced in the fields of genomics and oncoproteomics. Gene expression profiling with DNA microarray technology has allowed us to begin genetic profiling of colorectal cancer tissue. The response to chemotherapy can differ amongst individual tumors. For the first time researchers have begun to isolate and identify the genes responsible. New laboratory techniques allow us to isolate proteins preferentially expressed in colorectal cancer tissue. This could potentially lead to identification of a clinically useful protein biomarker in colorectal cancer screening and treatment.</p> <p>Conclusion</p> <p>If a set of discriminating genes could be used for characterization and prediction of chemotherapeutic response, an individualized tailored therapeutic regime could become the standard of care for those undergoing systemic treatment for colorectal cancer. New laboratory techniques of protein identification may eventually allow identification of a clinically useful biomarker that could be used for screening and treatment. At present however, both expression of different gene signatures and isolation of various protein peaks has been limited by study size. Independent multi-centre correlation of results with larger sample sizes is needed to allow translation into clinical practice.</p

Comparison of deposition images obtained by use of an ultrafine 99m-technetium-labeled carbon dry aerosol with ventilation images obtained by use of 81m-krypton gas for evaluation of pulmonary dysfunction in calves.

OBJECTIVE: To characterize the accuracy of an ultrafine 99m-technetium-labeled carbon dry aerosol for use in assessment of regional ventilation in calves with pulmonary dysfunction. ANIMALS: 7 Belgian White and Blue calves. PROCEDURE: The ultrafine aerosol was assessed by comparing deposition (D) images with ventilation (V) images obtained by use of 81 m-krypton (81mKr) gas via D-to-V ratio (D:V) image analysis in calves during spontaneous breathing (SB) and during experimentally induced pulmonary dysfunction (ePD). RESULTS: Mismatching index (LrTot) calculated on the D:V images revealed a good match (LrTot, 0.96 +/- 0.01) between D and V distribution patterns in calves during SB. Calculation of the ultrafine aerosol penetration index relative to 81mKr (PIRel) revealed preferential distribution of the ultrafine aerosol in lung parenchyma (PIRel, 1.13 +/- 0.11). In ePD, heterogeneity in the D:V distribution was observed (LrTot, 0.78 +/- 0.10) as a result of ultrafine aerosol particles impaction in airways as indicated by PIRel (0.66 +/- 0.16) and a proportion of pixels more radioactive in D images, compared with V images, that was located in the central part of the lung (475 +/- 77% in ePD vs 32.8 +/- 5.7% in SB). However, this central deposition did not prevent visual examination of the entire ventilated lung. CONCLUSIONS AND CLINICAL RELEVANCE: The ultrafine aerosol appears suitable for use in examination of ventilated parts of lungs of cattle, even those with impaired pulmonary function. However, airway impaction of ultrafine aerosol particles impedes the quantification of regional ventilation in cattle with abnormal lung function