Immunohistochemical study of nuclear factor-κB expression in esophageal squamous cell carcinoma: prognostic significance and sensitivity to treatment with 5-FU

Nuclear factor-κB (NF-κB) is expressed in many types of cancers. It has been suggested that the expression of NF-κB is associated with poor prognosis and resistance to chemoradiation therapies. This study evaluated the relationship between the expression of NF-κB and the prognosis and sensitivity of esophageal squamous cell carcinoma (ESCC) to chemotherapy. One hundred and nine ESCC specimens, from patients who had undergone radical esophagectomy, were divided into two groups depending on the expression of NF-κB. Surgical data and prognosis were compared between the two groups. NF-κB-positive tumors were detected in 61.5% of the cases. In 69 patients with stage II and III disease, 41 patients who were NF-κB-positive showed poor survival. The sensitivity of esophageal squamous cell carcinoma cell lines to 5-fluorouracil (5-FU) was analyzed by their NF-κB expression, and the effect of 5-FU was evaluated on the proliferation and activity of two cell lines of cultured ESCCs expressing NF-κB. ESCCs with activated NF-κB had poor sensitivity to 5-FU. These results suggest that the increased expression of NF-κB is associated with poor prognosis in patients with ESCC. NF-κB may be a target for ESCC therapy because of its selective expression in this type of cancer.

Expression of minichromosome maintenance 2 (MCM2), Ki-67, and cell-cycle-related molecules, and apoptosis in the normal-dysplasia-carcinoma sequence of the oral mucosa

OBJECTIVE

We examined cell cycle and cell death biomarker trends with the normal-dysplasia-carcinoma sequence of the oral epithelia analyzing the pathological significance of a new biomarker, minichromosome maintenance 2 (MCM2).

METHODS

This study analyzed 12 patients with normal oral epithelia, 69 with dysplasia, and 35 with squamous cell carcinoma (SCC); in 13 patients, SCCs were preceded by dysplasia. The sections were immunostained for MCM2, Ki-67, P53, P27(Kip1) and P21(CIP1/WAF1), and conducted by TUNEL methods. Western blot analysis of MCM2 was performed in the 4 human cultured oral SCCs, all of which showed the expression.

RESULTS

Significantly higher labeling indices (LI; %) of MCM2, Ki-67, and P53, as well as lower LI of TUNEL indices (TI; %), P27, and P21 were noted in the SCCs than in the dysplasias. The 13 dysplasias developed SCC with significantly higher LI of MCM2 and P53, and lower LI of P21 than the other dysplasias (each p < 0.05). The LI of MCM2, P21 and the TI were not correlated with P53 expression.

CONCLUSIONS

Oral dysplasia was characterized by lower cell proliferation and a higher frequency of cell death compared to SCCs. The higher LI of MCM2 and P53 and the lower LI of P21 might predict malignant transformation of oral dysplasia. MCM2 is regulated via a P53-independent pathway, and a useful biomarker of proliferating cells.

Telepathology for the biopsy specimens from human allografted kidney: effectiveness and pitfalls

This study was conducted to examine the validity and accuracy of telepathology for biopsy specimens from allografted kidney. The still video images of paraffin sections were transmitted via a two-way telephone by use of a digitized telephone network, ISDN. The quality of the transmitted images was sufficient for the diagnosis, especially at higher magnification. A total of 37 needle biopsy specimens from the 31 allografted kidneys were presented for consultation and diagnosed by an expert pathologist at Tottori University, until July 2000. The average number of transmitted images was 7.1 (range 3-12). Of the 37 specimens, diagnoses by telepathology agreed well with those made through direct microscopy in the 30 specimens. Insufficient or improper diagnosis was made in four specimens, in which proper and pathognomonic still images were not transmitted. Three cases were not diagnosed by telepathology because of the difficulty in making differential diagnosis. From these results, we concluded that telepathology is useful for transplantation pathology, in spite of limitations in some cases.

Identification of a novel human ankyrin-repeated protein homologous to CARP

We cloned a novel ankyrin repeat protein, Arpp, by immunoscreening a cDNA library constructed from a human esophageal carcinoma cell line, TE1, with an antibody directed to a hypothetical protein encoded by antisense p53 mRNA. Arpp protein is composed of 333 amino acids and contains four ankyrin-like repeat motifs in the middle portion of the protein, a PEST-like sequence and a lysine-rich sequence similar to a nuclear localization signal in the N-terminal region, and a proline-rich region containing consensus phosphorylation sites in the C-terminal region. Protein sequence analysis revealed that Arpp is homologous (52.7% identity) to Carp which is shown to be involved in the regulation of the transcription of the cardiac ventricular myosin light chain 2 gene. Arpp mRNA was found to be expressed in normal skeletal and cardiac muscle. Interestingly, Arpp expression was detectable in bilateral ventricles, but undetectable in bilateral atria and large vessels, suggesting that Arpp may play a specific function in cardiac ventricles as well as skeletal muscles.

Histopathology of a human allografted kidney with clinically sufficient function

To clarify the clinico-pathological significance of protocol biopsy and clinically silent rejection in the management of renal graft recipients, we selected a total of 139 (23%) from 604 biopsy specimens according to the following criteria: 1) less than 1.4 mg/dL of serum creatinine and 2) more than 1,500 mL/d of urine volume at time of biopsy. Clinical indications for the biopsy were classified into five categories: i) protocol biopsy (73 specimens), including 69 cases at discharge post-transplantation; ii) slight increase in serum creatinine (32); iii) proteinuria (20); iv) evaluation of pulse-therapy (13); and v) fever elevation (1). Except for the last category, the specimens were histopathologically diagnosed as being normal in 50 (68%), 6 (17%), 1 (5%), and 5 (38%) specimens, respectively. Even borderline changes, and mild acute rejection, as well as drug-induced nephropathy were included, implying the existence of clinically silent rejection or drug-induced nephropathy. Obvious diversity in the histopathological diagnosis was noted in category iii) showing proteinuria, which was mainly caused by chronic rejection, drug-induced nephropathy and glomerulonephritis. The graft survival rate was no different among the four categories, except for category v). These results indicate that biopsies obtained from functionally sufficient renal grafts could provide useful information in the management of the recipients. The clinical significance of protocol biopsy awaits further clarification by the analysis of a large number of cases.

Elastofibroma of the sigmoid colon

A case of elastofibroma occurring in the sigmoid colon of a 69 year-old woman is reported. The woman presented for survey of her gastrointestinal tract. Colonoscopy disclosed two polyps in the sigmoid colon, one of which was clinically considered to be recurrent adenoma. Histologically, the lesion had characteristic eosinophilic fibers and globules, termed elastofibroma fibers with hematoxylin and eosin stain. In addition, these elastinophilic materials were digested by elastase. Histological evaluation confirmed the diagnosis of elastofibroma. Our case might suggest that it is the result of long-term fibrosis after previous endoscopic resection of a sigmoid colonic adenoma.

Thymidine phosphorylase expression in human colorectal mucosa, adenoma and carcinoma: role of p53 expression

The enzyme, thymidine phosphorylase (dThdPase) is identical to platelet-derived endothelial cell growth factor (PD-ECGF), which acts as a potent angiogenic factor. The present study immunohistochemically examined the expression of dThdPase in human colorectal mucosa, adenomas and carcinomas, as well as six cultured colorectal carcinoma cell lines, in terms of intratumoral microvessel density (IMVD) and P53 expression. Thymidine phosphorylase was observed in lymphocytes, fibroblasts and macrophages, as well as smooth muscle cells and Schwann cells in the peripheral nerve fibers. The dThdPase-positive stromal cells apparently outnumbered the normal epithelial cells, adenoma and carcinoma cells with dThdPase. Weak but obvious cytoplasmic immunoreactivity was noted in a few normal colonic epithelia, predominantly the upper surface area, while a few adenoma cells showed weak nuclear immunostaining for dThdPase in six (24%) of the 25 colonic adenomas. Expression of dThdPase was noted in 33 (73.3%) of the 45 Dukes A and B, 14 (51.9%) of the 27 Dukes C and 14 (56.0%) of the 25 Dukes D carcinomas. The mean IMVD was 84.0 +/- 26.2 in the 36 dThdPase-negative carcinomas and 97.9 +/- 31.6 in the 61 dThdPase-positive carcinomas, the value being significantly higher in the latter group (P < 0.05). The frequency of dThdPase expression was significantly lower in the P53-negative carcinomas than in the positive carcinomas (P < 0.05). Western blot analysis showed the highest expression of dThdPase in LoVo carrying the wild-type p53 gene, followed by Colo201, Colo320, DLD-11 and WiDr carrying the mutated gene. These results indicate that: (i) the main source of dThdPase is stromal cells, including lymphocytes and macrophages in both colorectal normal and carcinoma tissues; (ii) dThdPase may take part in the induction of intratumoral microvessels, regardless of tumor stage; and (iii) expression might be modulated by not only P53 but also other molecules.

Hyperthermia-induced apoptosis occurs both in a p53 gene-dependent and -independent manner in three human gastric carcinoma cell lines

We examined the role of the p53 gene in hyperthermia-induced apoptosis using three human gastric carcinoma cell lines, MKN-28 (carrying mutated type p53 gene), MKN-74 (wild-type), and KATO-III (complete deletion). The results indicate that i) long-term hyperthermia causes necrosis, and short-term treatment induces apoptosis in a gradual time dependent fashion, ii) hyperthermia-triggered apoptosis can occur both in a p53 gene-dependent and -independent manner, and iii) up-regulation of Hsp70 might enhance the function of wild-type p53 protein in hyperthermia-induced apoptosis.

Frequent occurrence of apoptosis is an early event in the oncogenesis of human gastric carcinoma

We examined the relationship between apoptosis and the progression of human gastric carcinoma. Studies were conducted on a total of 88 surgically removed stomachs, comprising 26 minute (less than 5 mm in diameter), 29 early (limited to the mucosal and submucosal layer) and 33 advanced carcinomas. Apoptotic cells were visualized by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-digoxigenin nick end labelling (TUNEL). Serial sections were immunostained for p53 and Ki-67. The mean apoptotic indices (AI: percentage of TUNEL signal positive cells) of minute, early, and advanced carcinomas were 4.1 +/- 0.6, 3.8 +/- 1.2, and 4.0 +/- 1.2 in 46 well differentiated carcinomas, and 2.1 +/- 0.5, 2.7 +/- 0.9, and 2.2 +/- 1.1 in 42 poorly differentiated carcinomas, respectively. Similarly, the mean Ki-67 labelling indices (KI) were 39.2 +/- 7.8, 47.2 +/- 12.8, 52.6 +/- 13.1 in the former, and 35.0 +/- 9.3, 36.9 +/- 10.3, and 40.0 +/- 9.2 in the latter, respectively. Both mean AI and mean KI were significantly higher in well differentiated than in poorly differentiated carcinomas (P < 0.05). However, the value of mean AI did not differ among minute, early, and advanced carcinomas in either histological type, while KI increased gradually with tumour progression. The frequency of nuclear p53 expression did not differ among the three categories, implying that the gene mutation is an early event in gastric carcinogenesis. There was no statistical significance between nuclear p53 expression and mean AI. These results suggest that the progression of gastric cancer is defined by a gradual increase of proliferative activity and constant occurrence of apoptosis and that naturally occurring apoptosis is induced predominantly via a p53-gene-independent pathway.

Frequent occurrence of hepatocytic apoptosis in acute rejection of the grafted rat liver

The present study was conducted to examine the histopathological changes of rat liver grafts in the early post-transplantation period. A total of 44 orthotopic liver transplantations were performed using cuff techniques without anastomosis of the hepatic artery. They were divided into four groups: (i) group 1 (syngeneic, Lewis-->Lewis; n = 10); (ii) group 2 (allogeneic, ACI-->Lewis; n = 20); (iii) group 3 (allogeneic with immunosuppression, ACI-->Lewis; n = 12); and (iv) long-surviving grafts (PVG-->Lewis; n = 2). The histological findings were classified into four categories: (i) mild dilatation of Disse's spaces due to ischemia; (ii) bile duct proliferation; (iii) acute rejection; and (iv) zonal necrosis. Bile duct proliferation occurred on day 6 in all three groups and in one of the two long-surviving grafts (120 days). Acute rejection occurred on day 3 and progressed in groups 2 and 3. Zonal necrosis developed in group 2 after day 6, while acute rejection subsided after day 4 in group 3 receiving 15-deoxyspergualin. A few single cell deaths or acidophilic bodies were variably noted. Most of these cells showed signals by in situ nick end-labeling in their nuclei, implying the cells were undergoing apoptosis. The number of apoptotic hepatocytes increased as the progress and decreased with the regression of acute rejection in group 3. Thus, the extent of hepatocytic apoptosis may reflect the magnitude of acute rejection. More frequent distribution of apoptotic hepatocytes in periportal areas suggests that apoptosis may be induced by a variety of pathological stimuli, including the direct cytotoxic effects of lymphocytes, various cytokines and local circulatory disturbances.

Apoptosis in the human allografted kidney. Analysis by terminal deoxynucleotidyl transferase-mediated DUTP-botin nick end labeling

Apoptosis is a distinct form of cell death and occurs under a variety of physiological and pathological conditions. This study was conducted to examine the occurrence of apoptotic cell death in 44 formalin-fixed, paraffin-embedded biopsy specimens from allografted kidneys by the terminal deoxynucleiotidyl transferase (TdT)-mediated D-UTP-biotin nick end labeling (TUNEL) method. Careful observation of routine hematoxylin and eosin sections revealed a few apoptotic cells in cortical tubules. TUNEL signal was detected variably in tubular epithelia, and occasionally in lymphocytic cells and endothelium. The number of tubular epithelia demonstrating TUNEL signals was highest for cyclosporine tubulopathy, followed by acute rejection of very mild or mild grade, and then by chronic allograft nephropathy. Protocol biopsies from normally functioning grafts showed the least apoptotic cells, with the number being significantly lower than that of both cyclosporine tubulopathy (P < 0.01) and acute rejection (P < 0.05). Two specimens of acute accelerated rejection with diffuse hemorrhagic necrosis showed nonspecific signals in a few epithelia. These findings suggest that acute rejection or cyclosporine nephropathy not infrequently induces apoptosis of tubular epithelia, which might lead to tubular atrophy or loss, resulting in chronic transplant nephropathy.