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Few would dispute the efficacy of multimedia technology and the world wide web in promoting declarative knowledge or the acquisition of facts. It is the argument of this paper however that, apart from assisting a learner in "knowing that", these technologies are underestimated in their capacity to facilitate intellectual skills--procedural knowledge or "knowing how". Via examples from children employing information handling skills with a CD-ROM, this paper attempts to illustrate the ways in which new technologies support and enhance a range of skills associated with deep level processing and meaningful learning such as metacognition, problem solving and critical thinking. [ABSTRACT FROM AUTHOR]

Introduction: Colorectal cancer (CRC) is a highly heterogeneous disease, with pathologically similar cancers having completely different responses to treatment and patient survival. Intra-tumour heterogeneity (defined as distinct morphological and phenotypic differences) has recently been demonstrated to be an important factor in the development and behaviour of cancer cells and can be used to determine response to anticancer therapy. Method: Patients with resected CRC had DNA extracted from eight defined tumour areas which were analysed for two genetic mutations (BRAF and KRAS) and one epigenetic trait (CpG island methylator phenotype/CIMP). Normal adjacent tissue was studied as control. Results: Twelve patients with CRC were included. Intra-tumoural heterogeneity for KRAS mutation was seen in 2 patients (17%). There was no statistical evidence of CIMP status heterogeneity ( p = 0.85), but 6 of the 12 patients (50%) demonstrated at least one heterogeneous area within the tumour. Discussion: Intra-tumoural heterogeneity for both genetic and epigenetic factors in CRC is more prevalent than previously thought in Stage II and Stage III CRC. This study provides new insight into epigenetic heterogeneity of CRC and supports the development of a more targeted biopsy strategy to support expansion of personalised treatment. [ABSTRACT FROM AUTHOR]

Introduction Molecular characterisation of tumours is increasing personalisation of cancer therapy, tailored to an individual and their cancer. FOCUS4 is a molecularly stratified clinical trial for patients with advanced colorectal cancer. During an initial 16-week period of standard first-line chemotherapy, tumour tissue will undergo several molecular assays, with the results used for cohort allocation, then randomisation. Laboratories in Leeds and Cardiff will perform the molecular testing. The results of a rigorous pre-trial inter-laboratory analytical validation are presented and discussed. Methods Wales Cancer Bank supplied FFPE tumour blocks from 97 mCRC patients with consent for use in further research. Both laboratories processed each sample according to an agreed definitive FOCUS4 laboratory protocol, reporting results directly to the MRC Trial Management Group for independent crossreferencing. Results Pyrosequencing analysis of mutation status at KRAS codons12/13/61/146, NRAS codons12/13/61, BRAF codon600 and PIK3CA codons542/545/546/1047, generated highly concordant results. Two samples gave discrepant results; in one a PIK3CA mutation was detected only in Leeds, and in the other, a PIK3CA mutation was only detected in Cardiff. pTEN and mismatch repair (MMR) protein expression was assessed by immunohistochemistry (IHC) resulting in 6/97 discordant results for pTEN and 5/388 for MMR, resolved upon joint review. Tumour heterogeneity was likely responsible for pyrosequencing discrepancies. The presence of signet-ring cells, necrosis, mucin, edgeeffects and over-counterstaining influenced IHC discrepancies. Conclusions Pre-trial assay analytical validation is essential to ensure appropriate selection of patients for targeted therapies. This is feasible for both mutation testing and immunohistochemical assays and must be built into the workup of such trials. [ABSTRACT FROM AUTHOR]