Rie Kurabayashi

Changes of telomere length with aging.

We reviewed our methodology and results of telomere measurements, with reference to telomere length and aging. Human tissues always showed telomere shortening with age, except for the brain and myocardium. Yearly rates of telomere length reduction in various tissues were mostly within the range 20–60 bp, and thus compatible with that expected from only one round of mitosis. It was suggested that when telomeres were found to be longer in any specific organ in a given individual, then the other organs in that individual would also have longer telomeres. Using the quantitative fluorescence in situ hybridization (Q‐FISH) method for telomere measurement, we were able to measure the telomere lengths of various cell types within tissues. Here we summarize the results obtained for various cell types in the stomach, tongue and breast. Our Q‐FISH method using our original software program “Tissue Telo” is excellent for measuring telomere lengths using tissue sections and PNA probes. Geriatr Gerontol Int 2010; 10 (Suppl. 1): S197–S206.

Luminal and cancer cells in the breast show more rapid telomere shortening than myoepithelial cells and fibroblasts

Critically shortened, dysfunctional telomeres may play a role in the genetic instabilities commonly found in cancer. We analyzed 30 surgical specimens of invasive breast carcinoma from women aged 34 to 91 years and estimated telomere lengths as telomere-to-centromere ratio values in the 5 different cell types comprising breast tissue in order to clarify telomere length variations within and between individuals using our tissue quantitative fluorescence in situ hybridization method. We obtained 3 novel findings. (1) In corresponding normal tissues, telomere length decreased in the order myoepithelial cells > normal-appearing fibroblasts > luminal epithelial cells, and telomere lengths were characteristic in these 3 cell types within each individual. (2) As expected, cancer cells had significantly shorter telomeres than myoepithelial cells (P < .0001) and normal-appearing fibroblasts (P = .0161), but there was no significant difference in telomere length between luminal cells and cancer cells (P = .6270). (3) Fibroblasts adjacent to cancer had longer telomeres than normal-appearing fibroblasts distant from cancer (P < .0001). This study, which represents the first reported assessment of telomere length variations in the 5 cell types comprising breast tissue within and between individuals, revealed that normal luminal epithelial cells and cancer cells had the shortest telomeres. Our new findings indicate that telomeres of background luminal cells are as short as those of cancer cells. Tissue quantitative fluorescence in situ hybridization, applicable to analysis of individual cells in tissue sections, is considered to be a powerful technique with considerable promise for studies in oncology.

Oestrogen receptor-β1 but not oestrogen receptor-βcx is of prognostic value in apocrine carcinoma of the breast

Apocrine carcinoma of the breast, which frequently expresses oestrogen receptor‐β (ER‐β) in the absence of ER‐α and only infrequently is treated endocrinologically, gives an opportunity to investigate the clinicopathological role of ER‐β in breast cancer independent of ER‐α expression or tamoxifen treatment. Several isotypes of ER‐β, ER‐β1–5 etc., have been identified thus far; however, the clinicopathological importance of each ER‐β isotype in breast cancer is still uncertain. Here we aimed to clarify the clinicopathological importance of ER‐β1 and ER‐βcx (ER‐β2) in apocrine carcinomas, immunohistochemically examining expressions of ER‐β1 and ER‐βcx in 47 apocrine carcinomas. Positivity for ER‐β1 and ER‐βcx was observed in 41 (87%) and 18 (38%) of 47 cases, respectively. ER‐β1 positivity was related to smaller tumor size (P=0.0359), lower histological grade (P=0.0322), and higher disease‐free survival (P<0.0001), whereas ER‐βcx status was related to none of these parameters. ER‐β1 positivity was also associated with favorable clinical outcome in 24 so‐called triple‐negative (ER‐α‐negative/PR‐negative/HER2‐negative) apocrine carcinomas. ER‐β1 itself, independent of ER‐α expression and tamoxifen treatment, seems to have a tumor‐suppressive effect, at least in apocrine carcinomas. Further study of ER‐β1 is desired to optimize breast cancer treatment.

Telomere Metabolism and Diagnostic Demonstration of Telomere Measurement in the Human Esophagus for Distinguishing Benign from Malignant Tissue by Tissue Quantitative Fluorescence in situ Hybridization

Objective: We have developed a novel method for evaluating telomere length in four different cell types in non-cancerous and cancerous mucosal tissue from 15 cases of squamous cell carcinoma of the esophagus using tissue quantitative fluorescence in situ hybridization (Q-FISH). We hypothesized that the very rapid cell proliferation observed in esophageal squamous cell carcinomas might accelerate the telomere shortening and chromosomal instability associated with carcinogenesis. Methods: Tissue Q-FISH and the telomere to centromere intensity ratio (TCR) were used to compare telomere shortening in tissue sections taken from esophageal squamous cell carcinomas and adjacent non-cancerous esophageal tissues. Results: The peak percentage of TCR was <1 for esophageal squamous carcinoma cells and >1 for the non-cancerous esophageal cell types. Basal layer cells had the longest telomeres in comparison with prickle, cancer, and stromal cells, and strongly expressed hTERT, cytokeratin 14 and CD49f, but not MIB-1. Conclusion: These results suggest the presence of stem cells in the basal layer of the esophagus. Esophageal squamous cell carcinomas also display anaphase bridges, evidencing chromosomal instability.In conclusion, our TCR method can be used to distinguish between benign and malignant tissue in esophageal lesions. In order to apply this approach clinically to individual cases, further studies are in progress.

Des-gamma carboxy prothrombin (PIVKA-II)- and alpha-fetoprotein (AFP)-producing gastric cancer

To the Editor: Since Liebman et al.1 reported, in 1984, that protein induced by vitamin K absence or antagonist-II (PIVKA-II) was increased in the plasma of hepatocellular carcinoma (HCC) patients, PIVKA-II has been regarded as a new tumor marker of HCC. Although case reports of α-fetoprotein (AFP)-producing gastric cancer have been gradually increasing, PIVKA-IIproducing gastric cancer is very rare. In this report, we describe a case of PIVKA-IIand AFP-producing gastric cancer. A 61-year-old man was hospitalized with the chief complaint of appetite loss. Barium study and upper digestive tract endoscopy revealed a 10-cm-sized Borrmann type-3 gastric cancer. Hepatic masses up to 8 8 6-cm in size were also detected by abdominal computed tomography and ultrasonography. AFP and PIVKA-II values in the serum were abnormally high (AFP, 495.2 ng/ml [L2 subfraction, 21.4%; L3 subfraction, 75.6%]; normal value, 20 ng/ml; PIVKA-II, 635 mAU/ml; normal value, 40 mAU/ml). Thus, total gastrectomy and liver biopsy were performed. In the resected specimen, an 8.0 7.0/9.5 8.5-cm-sized Borrmann type-3 gastric cancer occupied mainly the posterior wall from the upper gastric body to the pyloric antrum (Fig. 1). Histologically, tumor cells proliferated to form tubular, papillary, trabecular, and solid structures. Immunohistochemically, AFPpositive tumor cells and PIVKA-II-positive tumor cells were found; the AFP-positive tumor cells were distributed mainly in the trabecular or solid structure and the PIVKA-II-positive tumor cells were distributed mainly in the tubular structure (Fig. 2). The tumor in the liver showed a structure similar to that of the gastric tumor; however, immunohistochemical staining for AFP and PIVKA-II was negative. Adjuvant chemotherapy was performed; however, the residual hepatic tumor enlarged and the patient died 6 months after the diagnosis. We made a pathological diagnosis of PIVKA-IIand AFPproducing gastric carcinoma with liver metastasis for this patient. Although AFP and PIVKA-II production in the liver tumor was not confirmed immunohistochemically, the following findings suggested that it was a metastatic tumor: (1) the histological structures of the gastric and hepatic tumors were similar, (2) hepatitis virus markers were all negative, (3) there was no remarkable change in the nontumorous liver tissue pathologically. The cause of the negative staining for AFP and PIVKA-II in the liver tumor was probably sampling limitations. In recent years, the mechanism of AFP production in most cases of AFP-producing gastric carcinoma has been assumed to be retrodifferentiation to yolk sac tumor or fetal gastrointestinal tract, as determined by the investigation of AFP-lectin combination. However, the AFP subfraction pattern in the present patient resembled that of HCC; so, hepatoid metaplasia may have been the cause of the AFP production in this particular patient. The mechanism by which gastric cancer acquires the ability to produce PIVKA-II is unknown. Some researchers have suggested that the mechanism of hepatocellular metaplasia is involved. However, in Fig. 1. Macroscopic view of the gastric cancer. An 8.0 7.0/9.5 8.5-cmsized Borrmann type-3 cancer occupies mainly the posterior wall from the upper gastric body to the pyloric antrum