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Purpose Evaluation of the relationships existing among 3 histologic types of urothelial tumors, chromosomal instability, and telomere length. Patients and methods We examined 37 consecutive cases of papillary urothelial neoplasm, from which 26 (70.3%) were suitable for karyotype analysis, comprising 7 papillary urothelial neoplasms of low malignant potential (PUNLMPs), 10 low-grade papillary urothelial carcinomas (PUCs), and 9 high-grade PUCs. We performed karyotype and anaphase bridge analyses, and measured telomere lengths by quantitative fluorescence in situ hybridization. Results PUNLMPs were always diploid and had anaphase bridges. Low-grade PUCs showed diploidy ( n = 2), hypoploidy ( n = 4) and polyploidy ( n = 4), and high-grade PUCs showed diploidy ( n = 1) and polyploidy ( n = 8); both had anaphase bridges. The incidence of anaphase bridges did not differ significantly between PUNLMPs and high-grade PUCs ( P = 0.105). The telomere lengths of PUNLMP, low-grade PUC, and high-grade PUC, expressed as mean telomere fluorescence units (TFU)±SD, were 7906±3197, 4893±1567, and 3299±1406, respectively. The differences among the 3 groups were significant. However, 42.9% of the PUNLMPs had shorter telomeres than the mean value for low-grade PUCs, and 30.0% of the low-grade PUCs had shorter telomeres than those for high-grade PUCs. There was an inverse correlation between telomere length and the incidence of anaphase bridges. Conclusions PUNLMP appears to progress to low-grade PUC and high-grade PUC in association with telomere shortening and chromosomal instability. Our data suggest that critically shortened telomeres cause chromosomal instability during progression of papillary urothelial neoplasms.

We monitored the telomere lengths and chromosomal instability characteristics of fibroblasts at different population doubling levels (PDLs) to gain further insight into the role of telomere shortening in chromosomal instability. We used 7 normal diploid human fibroblast strains (TIG-1, 3, 7, 103, 104, 112, and 114) and a quantitative fluorescence in situ hybridization method to measure telomere lengths of the p- and q-arms of individual chromosomes. We also enumerated morphologic signs of chromosomal instability, including fusion or loss of chromosomes, and anaphase bridges. In strains TIG-1, 3, 7, 103, and 114 at the late (phase 3) stage (≧40PDLs), 29 (96.6%) of 30 fusions were associated with one or both of the chromosomal arms that bear significantly shorter telomeres in those populations. In TIG-1 at 62PDL, 6 fusions were associated with Xq (n=3), 21q (n=3), and other (n=6) chromosomes. Xq and 21q had significantly shorter telomeres, and anaphase bridges were often associated with chromosomes X and/or 21 (74.6%). Our results indicate that chromosomes having excessively shortened telomeres at late PDLs begin to show features of instability such as fusions and anaphase bridges.

We investigated the telomere lengths of individual cell types in lingual mucosa using an improved tissue quantitative fluorescence in situ hybridization (Q-FISH) method. Our tissue Q-FISH method compensates for partially cut nuclei in a tissue section by using the telomere:centromere ratio (TCR). We normalized our TCR measurements (NTCR) using a section from a block of cultured cells placed on the same slide, thus improving the accuracy and reproducibility of the results. Normal lingual mucosa was obtained from 21 autopsied individuals. Immunohistochemistry showed positivity mainly for p27, p63, and CK19 in basal cells, and for Ki-67 in parabasal cells. Q-FISH revealed that NTCR was significantly highest in basal cells and lowest in prickle cells, and also that telomere length regressed at a certain rate in each cell type, firstly. Significant correlations of NTCR among the three epithelial cell types were demonstrated. The present findings appear to support the theory that stem cells exist in the basal layer of the lingual epithelium. The reduction of telomere length with age and in each cell layer is consistent with the telomere biology theory of cell proliferation and differentiation in oral mucosa.

Many studies have demonstrated the association between telomere length in mitotic cells and carcinogenesis and mortality, but little attention has been focused on post-mitotic cells and human life expectancy. We assessed the relationship between telomere length in cerebral gray and white matter and longevity in 72 autopsied Japanese patients aged 0–100 years using Southern blot hybridization. The mean telomere lengths in the gray and white matter were 12.3 ± 2.5 kilobase pairs and 11.4 ± 2.1 kilobase pairs, respectively. The mean telomere lengths in 60–69 year decadal group were less than those of neonates, and declined further in the 70–79-year age group, but those in groups of further advanced age were longer than in the 70–79 year group (70–79 < 80–89 < 90–100 years of age). Thus, the 90–100-year age group possessed significantly longer telomeres than the 70s (p = 0.029). Autopsy protocols showed a decrease in the rate of cancer death in individuals in their 80s (p = 0.041) and 90s (p = 0.017) versus those in their 60s, and in their 80s the mean telomere length in the gray matter from cancer death patients was significantly shorter than that of patients who died of other diseases (p = 0.04). These data suggest that innate telomere lengths are maintained very well in the cerebrum, and are associated with longevity. Our study lends indispensable support to the hypothesis that longer telomeres protect the genome from instability (a major cause of carcinogenesis) and are beneficial for longevity.

We investigated progressive telomere shortening in normal human epidermis and lingual epithelium during aging, and attempted, in particular, to ascertain whether the telomere shortening that accompanies aging occurs at the same rate in different tissues. We studied telomeric DNA integrity, and estimated annual telomere loss, in 52 specimens of epidermis and 48 specimens of lingual epithelium collected at autopsy from subjects who had died at ages between 0 and 101 y. Most of the DNA samples were measured twice by southern blot hybridization. In addition, the correlation between telomere lengths in the two types of tissues was examined. The telomere reduction rates in epidermis and lingual epithelium were 36 bp and 30 bp per y, respectively, and these were significantly different. The rates obtained by the second measurements in epidermis and lingual epithelium were 39 and 32 bp per y, respectively, and these were also significantly different. The mean telomere lengths in the epidermis of eight neonates and the lingual epithelium of seven neonates were 13.2+/-1.0 and 13.8+/-1.0 kb, respectively. Comparison of telomere lengths in the two tissues for 41 paired samples showed that the mean telomere length in the epidermis (10.7+/-2.3 kb) was less than that in the lingual epithelium (12.4+/-2.5 kb); however, statistical analysis revealed a very significant relationship between epidermal and lingual epithelial telomere length (r=0.842, p0.0001). These results indicate that the telomeres in epidermis and lingual epithelium are characterized by tissue-specific loss rates.

We previously described two types of age-related cell surface changes which could be revealed in human diploid fibroblasts by concanavalin A-mediated red blood cell (RBC) adsorption with the RBC and fibroblast coating methods. The role of cell surface morphology on these age-related cell surface phenomena and the difference between the results with the two coating methods was examined with scanning and transmission electron microscopy. RBC adsorption with either method occurred to all parts of cell surfaces, and there was no special loci for the adsorption. In addition, RBC adsorption was found to occur either being mediated or unmediated by microvilli, regardless of the coating method. The results suggest that surface morphology plays no role in age-related changes in RBC adsorption and the difference between the results with the two coating methods.