Histologic characteristics of non-microsatellite-instable colon adenomas correlate with distinct molecular patterns.

Colon carcinogenesis encompasses the stepwise accumulation of genomic aberrations correlated with the transition of aberrant crypt-adenoma-carcinoma. Recent data have revealed that, in addition to the microsatellite-instable phenotype, the chromosome instability pathway, representing four fifth of the colon carcinoma, could be involved in heterogeneous molecular alterations. Our project was aimed at determining the existence of distinct molecular subtypes in 159 non-microsatellite-instable colon polyps and their correlation with histology and dysplasia, using allelotyping, MGMT promoter gene methylation status, and K-RAS mutation analyses.

Evidence for various 20q status using allelotyping, CGH arrays, and quantitative PCR in distal CIN colon cancers.

The genomic aberration profile of chromosome 20q in distal CIN colon carcinomas was analysed using allelotyping and CGH arrays. Allelotyping revealed carcinomas with allelic imbalance along the full long arm, and carcinomas with fully non-aberrant 20q. Oligonucleotide-based CGH showed that among the carcinomas without allelic imbalance, 47% had in fact a gain.

Marked activity of irinotecan and rapamycin combination toward colon cancer cells in vivo and in vitro is mediated through cooperative modulation of the mammalian target of rapamycin/hypoxia-inducible factor-1alpha axis.

Purpose: Despite recent progress, colon cancer is often resistant to combination chemotherapy, highlighting the need for development of novel therapeutic approaches. An attractive target is hypoxia-inducible factor-1alpha (HIF-1alpha), a key transcription factor with a pivotal role in tumor cell metabolism. One potential class of therapeutic agents targeting HIF-1alpha are mammalian target of rapamycin inhibitors such as rapamycin.

IR spectral imaging for histopathological characterization of xenografted human colon carcinomas.

This study aims to develop IR imaging of tumor tissues for generating an automated IR-based histology. Formalin-fixed paraffin-embedded xenografts of human colon carcinomas were analyzed. Chemometric and statistical multivariate treatments of spectral data permitted to probe the intrinsic chemical composition of tissues, directly from paraffinized sections without previous dewaxing.