Genome-wide association studies have revealed that many low-penetrance cancer susceptibility loci are located throughout the genome; however, a very limited number of genes have been identified so far.,Using a forward genetics approach to map such loci in a mouse skin cancer model, we previously identified strong genetic loci conferring resistance to early-stage chemically induced skin papillomas on chromosome 7 with a large number of [(FVB/N×MSM/Ms)×FVB/N] F1 backcross mice.,In this report, we describe a combination of congenic mapping and allele-specific alteration analysis of the loci on chromosome 7.,We used linkage analysis and congenic mouse strains to refine the location of Stmm1 (Skin tumor modifier of MSM 1) locus within a genetic interval of about 3 cM on proximal chromosome 7.,In addition, we used patterns of allele-specific imbalances in tumors from F1 backcross and N10 congenic mice to narrow down further the region of Stmm1 locus to a physical distance of about 5.4 Mb.,To gain the insight into the function of Stmm1 locus, we carried out a long term BrdU labelling experiments with congenic mice containing Stmm1 locus.,Interestingly, we observed a decrease of BrdU-LRCs (Label Retaining Cells) in a congenic strain heterozygous or homozygous for MSM allele of Stmm1.,These results suggest that Stmm1 responsible genes may have an influence on papillomagenesis in the two-stage skin carcinogenesis by regulating epidermal quiescent stem cells.
Reflectance-mode confocal microscopy (RCM) is a new in vivo skin imaging technique.,We present our one-year experience in RCM examinations in skin tumors and the retrospective analysis of patients enrolled in the Dermatological Department of ‘N.,Paulescu’ Institute using the Fotofinder Dermoscope IIŴ for the dermatoscopy analysis and VivaScope 1500Ŵ  for in vivo RCM.,We established the rank of RCM in the complex algorithm of skin cancer diagnose, showing that the presented experience can open new possibilities to implement this automated image analyzing system in the routine practice.,Our analyzed cases clearly showed that confocal microscopy, therefore, optical biopsy, could guide the clinician towards an accurate diagnosis before surgical removal.,Moreover, we emphasized that the development of this technique increases the potential of future teledermatologic applications.