Cross-class inhibition of the cysteine proteinases cathepsins K, L, and S by the serpin squamous cell carcinoma antigen 1: a kinetic analysis

The human squamous cell carcinoma antigens (SCCA) 1 and 2 are tandemly arrayed genes that encode two high-molecular-weight serine proteinase inhibitors (serpins). Although these proteins are 92% identical, differences in their reactive site loops suggest that they inhibit different types of proteinases. Our previous studies show that SCCA2 inhibits chymotrypsin-like serine proteinases [Schick et al. (1997) J. Biol. Chem. 272, 1849-1855]. We now show that, unlike SCCA2, SCCA1 lacks inhibitory activity against any of the more common types of serine proteinases but is a potent cross-class inhibitor of the archetypal lysosomal cysteine proteinases cathepsins K, L, and S. Kinetic analysis revealed that SCCA1 interacted with cathepsins K, L, and S at 1:1 stoichiometry and with second-order rate constants >/= 1 x 10(5) M-1 s-1. These rate constants were comparable to those obtained with the prototypical physiological cysteine proteinase inhibitor, cystatin C. Also relative to cystatin C, SCCA1 was a more potent inhibitor of cathepsin K-mediated elastolytic activity by forming longer lived inhibitor-proteinase complexes. The t1/2 of SCCA1-cathepsin S complexes was >1155 min, whereas that of cystatin C-cathepsin complexes was 55 min. Cleavage between the Gly and Ser residues of the reactive site loop and detection of a stable SCCA1-cathepsin S complex by sodium dodecyl sulfate-polyacrylamide gel electrophoresis suggested that the serpin interacted with the cysteine proteinase in a manner similar to that observed for typical serpin-serine proteinase interactions. These data suggest that, contingent upon their reactive site loop sequences, mammalian serpins, in general, utilize their dynamic tertiary structure to trap proteinases from more than one mechanistic class and that SCCA1, in particular, may be involved in a novel inhibitory pathway aimed at regulating a powerful array of lysosomal cysteine proteinases.     

Physical and functional association between thymic shared antigen-1/stem cell antigen-2 and the T cell receptor complex

Thymic shared antigen-1 (TSA-1)/stem cell Ag-2 (Sca-2) is a glycosylphosphatidylinositol (GPI)-anchored antigen expressed on lymphocytes. We have previously demonstrated that a signal via TSA-1/Sca-2 inhibits T cell receptor (TCR)-mediated T cell activation and apoptosis. To elucidate a molecular mechanism for TSA-1-mediated modulation of the TCR-signaling pathway, we examined whether TSA-1 is physically coupled to the TCR in the present study. TSA-1 was clearly associated with CD3zeta chains in T cell hybridomas, activated T cells, and COS-7 cells transfected with TSA-1 and CD3zeta cDNA. The physical association was confirmed on the surface of T cells in immunoprecipitation and confocal microscopy. The analysis using stable and transient transfectants expressing a transmembrane form of TSA-1 revealed that the association of CD3zeta did not require the GPI anchor of TSA-1. Finally, tyrosine phosphorylation of CD3zeta chains was induced after stimulation with anti-TSA-1, suggesting that a functional association between these two molecules also exists. These results imply that the physical association to CD3zeta underlies a regulatory role of TSA-1/Sca-2 in the TCR-signaling pathway.     

Molecular regulation of the interaction between leukocyte function-associated antigen-1 and soluble ICAM-1 by divalent metal cations

Surface plasmon resonance (SPR) was used to investigate and characterize the interaction between LFA-1 and sICAM-1 (a soluble form of ICAM-1). Full-length LFA-1 was immobilized on a hydrophobic surface, and sICAM-1 binding was monitored in a flow cell format. The binding of sICAM-1 to LFA-1 was specific and dependent upon Mg2+; Abs to both sICAM-1 and LFA-1 blocked the interaction, and EDTA abolished all binding. Association and dissociation rate constants (k(a) and k(d), respectively) for sICAM-1 were 2.24 x 10(5) M(-1) s(-1) and 2.98 x 10(-2) s(-1), respectively, giving a calculated K(ICAM) of 133 nM. Since the LFA-1/ICAM-1 interaction is highly sensitive to the presence of metal cations, SPR was also used to probe the affinity of the metal binding sites. The K(Mg) values were 160 and 12 microM in the absence (EGTA) and the presence of Ca2+ (100 microM), respectively; in addition, K(Mn) was 2 microM in the presence of Ca2+ (100 microM). Increasing Ca2+ into the millimolar concentration range, however, resulted in a competitive displacement of Mg2+/Mn2+ and decreased sICAM-1 binding. Based on these data, a synergistic model for the molecular regulation of LFA-1 by divalent metal cations is proposed, and implications to cellular adhesion are discussed.     

Growth inhibitory concentrations of EGF induce p21 (WAF1/Cip1) and alter cell cycle control in squamous carcinoma cells

Previous studies have reported inhibition of A431 squamous carcinoma cell growth by nanomolar concentrations of epidermal growth factor (EGF), a potent mitogen for cells of epithelial origin. In this study, we examined potential mechanisms through which inhibition of keratinocyte growth mediated by EGF might occur by analysing components of the cell cycle regulatory machinery in A431, HN6 and HN30 keratinocytes in the presence of growth inhibitory or growth stimulatory doses of EGF. Treatment of cells with 25 pM EGF produced an increase in [3H]thymidine incorporation in A431, HN6 and HN30 cells, with respect to control cultures. Exposure to 2.5 nM EGF reduced [3H]thymidine incorporation in A431 cells and HN6 cells to 11% and 70% of control levels, respectively, whereas HN30 cells continued to proliferate in the presence of EGF. [3H]thymidine incorporation assays carried out over 24 h revealed repression of DNA synthesis in A431 cells after 12 h exposure to 2.5 nM EGF compared to untreated cells. Flow cytometry studies demonstrated accumulation of cells in G0/G1 after addition of 2.5 nM, but not 25 pM EGF. Western blot analysis revealed elevation of p21 (WAF1/CIP1/SDI1) protein levels in A431 and HN6 cells under growth-inhibitory conditions. Stimulatory doses of EGF did not induce p21 in these cells. Northern blot hybridization demonstrated elevated levels of p21 mRNA within 4 h of exposure of A431 cells to 2.5 nM EGF, which remained elevated above basal levels at 24 h. In vitro kinase assays demonstrated temporal differences in CDK2 and CDK6 activities which were related to EGF concentration. Immunocomplex Western blotting demonstrated increased association of p21 with CDK2 and CDK6 in A431 cells treated with 2.5 nm EGF. Furthermore, temporal alterations in the association of PCNA with p21 and with CDK6 were observed. The data indicate that p21 is a likely mediator of EGF-induced growth-inhibition, probably through mechanisms involving sequestration of PCNA and inhibition of CDK activity.     

Differentiation between chondroma and squamous cell carcinoma: evaluation of subtraction image of MRI

The image processing procedure has become widely applied as a visual aid in imaging diagnosis. The subtraction image of MRI obtained by digitally subtracting an unenhanced image from a contrast-enhanced image, depicted a discrete distribution of the contrast agent. Subtraction images in the clinical cases were compared. The subtraction image in a case of chondroma demonstrated a relatively uniform distribution of a contrast agent, with a well delineated neoplastic lesion. The subtraction image in a case of squamous cell carcinoma, the contrast agent was distributed heterogeneously in the carcinoma and well permeated into the muscle. Different patterns of subtraction image were obtained in the clinical cases of chondroma and squamous cell carcinoma in this study. The findings suggest the potential usefulness of the subtraction image for diagnosing the degree of malignancy.     

Use of flow cytometry in the analysis of stage III squamous cell carcinoma of the oesophagus and its association with MIB-1

AIMS: To examine the prognostic and pathobiological importance of DNA content in oesophageal squamous cell carcinomas in Hong Kong Chinese subjects; to evaluate its association with the immunohistochemical proliferative marker MIB-1. METHODS: Paraffin wax embedded tumour tissue and adjacent normal tissue (control tissue) samples from 45 resected stage III oesophageal squamous cell carcinomas were studied using flow cytometric analysis. The DNA content and the clinicopathological data of these patients were analysed together with the MIB-1 labelling index. RESULTS: DNA aneuploidy was present in 14 (31%) of the 45 cases. However, the DNA content did not correlate significantly with the age, sex, or survival of the patients, nor the length, location, differentiation and MIB-1 labelling index of the oesophageal carcinomas. The synthetic (S) phase fraction of diploid tumours bore no relation to the patients' survival or MIB-1 score. CONCLUSIONS: Flow cytometry was not as useful as the MIB-1 labelling index in predicting the biological characteristics of the tumours and the prognosis of patients with oesophageal squamous cell carcinomas. This study does not support the routine use of DNA flow cytometric analysis in oesophageal cancers.     

Myasthenia gravis and primary squamous cell carcinoma of the thymus

Occurrence of primary squamous cell carcinoma of the thymus gland in a 65-year-old man with myasthenia gravis is reported. Histologic and immunohistochemical studies confirmed the diagnosis of a differentiated squamous cell carcinoma. Extensive clinical investigations ruled out another primary site for the tumor. The patient made a full recovery postoperatively. Only three cases of primary squamous cell carcinoma of the thymus gland in association with myasthenia gravis have been reported in the literature.     

The multicentric occurrence of squamous epithelial dysplasia and squamous cell carcinoma in the esophagus

BACKGROUND: The biologic significance of esophageal dysplasia has not yet been completely elucidated, especially regarding the process of multiple occurrences of squamous cell carcinoma. METHODS: The multiplicity of dysplasia in 73 patients with solitary carcinoma of the esophagus (Group I) and 21 with multiple carcinomas (Group II) was compared in surgically resected specimens. RESULTS: Thirty-nine second carcinomas were identified in 13 patients of Group II, and all were superficial. The incidences of five or more isolated dysplasias in cases without continuity to a carcinomatous lesion, was 6.8% and 66.7% in Groups I and II, respectively (P < 0.01). In a case with three or more carcinomas, the incidence increased to 84.6%. The coexistence of all grades of isolated dysplasias was observed in 10 patients (47.6%) in Group II but in only 6 patients (8.2%) in Group I (P < 0.01). CONCLUSIONS: These findings suggest that various degrees of evolving biologically related lesions, such as dysplasia and carcinoma, can occur multicentrically in the same esophagus.     

Immunohistochemical staining for desmogleins 1 and 2 in keratinocytic neoplasms with squamous phenotype: actinic keratosis, keratoacanthoma and squamous cell carcinoma of the skin

Desmosomes are intercellular junctions that have been shown to be down-regulated in certain types of carcinoma and that may play a role in suppression of invasion and metastasis. This paper describes an immunohistochemical study of three types of epidermal neoplasms with monoclonal antibody to desmoglein in order to determine how desmosomal staining correlates with the clinical, biological and histopathological features of these neoplasms. Actinic keratosis (AK) is the most common keratinocytic premalignant neoplasm that was reported to have a 10-20% rate of malignant transformation into squamous cell carcinoma (SCC). Keratoacanthoma (KA) is a benign neoplasm that involutes spontaneously after a few months of rapid growth. SCC is a malignant tumour capable of metastasis. Electron microscope studies of KA and SCC showed significantly reduced staining for desmosomes in SCC but not in KA. We have examined staining for desmoglein using the monoclonal antibody 33-3D, a mouse IgM monoclonal antibody, that recognizes the cytoplasmic domains of desmoglein (Dsg)1 and Dsg2 on frozen sections. Immunohistochemical staining of normal skin with this antibody revealed strong pericellular localization of the antigen, outlining the cell membranes of the keratinocytes. A series of 30 AKs, 12 KAs and 24 SCCs was stained immunohistochemically with 33-3D monoclonal antibody. All examined KAs showed extensive pericellular staining for Dsg. By contrast, juxtanuclear staining for Dsg was noted in 12 SCCs, and completely negative staining in seven SCCs. The five remaining SCCs showed focal pericellular staining for the Dsg marker. The most common finding in AK was focal pericellular staining for Dsg, with complete absence of staining in dysplastic areas (25 cases). In five cases negative pericellular staining in dysplastic areas was associated with juxtanuclear accumulation of the Dsg marker. A strong negative correlation between Dsg staining and degree of dysplasia was obtained. The Dsg pattern in KA is similar to normal epidermis and shows a clear difference between KA and SCC. AK has a limited loss of Dsg expression in a SCC-like pattern that is congruent with its premalignant nature. As the stain works on frozen tissue, it may be helpful for rapid differentiation in selected cases in cutaneous oncology and Mohs micrographic surgery. This antibody may also have great potential for the detection of the effects of chemopreventive agents in skin cancer.     

Diet, reflux and the development of squamous cell carcinoma of the oesophagus in Africa

BACKGROUND: Squamous cancer of the oesophagus has reached epidemic proportions in Africa in the past few decades. There are many known associations but as yet no well established theory of causation. METHODS: Relevant literature was found by manual review of appropriate journals and literature, Medline searches and cross-referencing. Published theories of causation of endemic cancer of the oesophagus were assessed in the light of available evidence. A hypothesis based on that evidence was formulated. RESULTS AND CONCLUSION: A predominantly maize-based diet is high in linoleic acid, a precursor for gastric prostaglandin synthesis. In combination with low intake of other fatty acids and riboflavin, high levels of prostaglandin E2 are produced in gastric mucosa, leading to reduced gastric acid secretion, relaxation of the pylorus and a reduction in lower oesophageal sphincter pressure. These events result in combined reflux of duodenal and gastric juices low in acidity into the oesophagus. Resulting dysplasia strongly predisposes to local squamous carcinogenesis. This is now a fertile area for research, which may open the way for preventive action.     

Contribution to activity of histidine-aromatic, amide-aromatic, and aromatic-aromatic interactions in the extended catalytic site of cysteine proteinases

Within the papain family of cysteine proteinases few other residues in addition to the catalytic triad, Cys25-His159-Asn175 (papain numbering) are completely conserved [Berti & Storer (1995) J. Mol. Biol. 246, 273-283]. One such residue is tryptophan 177 which participates in a Trp-His-type interaction with the catalytic His159. In all enzymes of this class for which a three-dimensional structure has been reported, an additional highly conserved tryptophan, Trp181, also interacts with Trp177 via an aromatic-aromatic interaction in which the planes of the indole rings are essentially perpendicular. Also, both indole rings participate as pseudo-hydrogen bond acceptors in interactions with the two side chain amide protons of Asn175. Clearly, the proximity of Trp177 and Trp181 to the catalytic triad residues His159 and Asn175 and their network of interactions points to potential contributions of these aromatic residues to catalysis. In this paper, using cathepsin S, a naturally occurring variant that has a phenylalanine residue at position 181, we report the kinetic characterization of mutants of residues 175, 177, and 181. The results are interpreted in terms of the side chain contributions to catalytic activity and thiolate-imidazolium ion-pair stability. For example, the side chain of Asn175 has a major influence on the ion-pair stability presumably through its hydrogen bond to His159. The magnitude of this effect is modulated by Trp177, which shields the His159-Asn175 hydrogen bond from solvent. The His159-Trp177 interaction also contributes significantly to ion-pair stability; however, Trp181 and its interactions with Asn175 and Trp177 do not influence ion-pair stability to a significant degree. The observation that certain mutations at positions 177 and 181 result in a reduction of kcat/Km but do not appear to influence ion-pair stability probably reflects the contributions of these residues to substrate binding.     

Carcinoma of the lung in Okinawa, Japan: with special reference to squamous cell carcinoma and squamous metaplasia

In Okinawa, a subtropical island in southern Japan, squamous cell carcinoma (SCC), especially the well-differentiated form, is prevalent, while this form is relatively rare in both the mainland and other countries (e.g. United States of America). More patients with SCC from Okinawa, moreover, were positive for human papillomavirus (HPV) DNA by polymerase chain reaction (PCR) (79%), and harbored HPV types 6, 16 and 18, in combination. On the other hand, less than 30% of the mainland patients were positive for HPV DNA by PCR. Those patients who were positive all harbored only one HPV type. Furthermore, in Okinawa, there were a significant number of cases with adenosquamous carcinoma, and they too were positive for HPV DNA. The SCC and the adenocarcinoma cells adjacent to the SCC component in these cases were also positive for HPV DNA, and such adenocarcinoma cells were enlarged in size with relatively wide cytoplasm. The authors postulate that HPV infects adenocarcinoma cells and changes them to enlarged cells, followed by squamous metaplasia. In this report, HPV DNA was transfected to adenocarcinoma cells (cultured cell lines) and this showed that HPV causes squamous metaplasia. In addition, aberrant expression of p53 was demonstrated in a large number of the SCC cases in Okinawa. The enlarged adenocarcinoma cells adjacent to the SCC components in adenosquamous carcinomas also showed aberrant expression of p53. The recent advances in the studies of anti-oncogenes, p53, etc. and oncogenes are outlined. It is to be noted that the molecular mechanisms of carcinogenesis in the lung have been studied in general, classifying lung tumors into two groups, namely, small cell carcinoma (SCLC) and non-small cell carcinoma (NSCLC). However, because human lung cancer is represented by a wide variety of histologic types, molecular genetic studies according to a more detailed histological subclassification is needed.     

Involvement of lymphocyte function-associated antigen-1 and intercellular adhesion molecule-1 in osteoclastogenesis: a possible role in direct interaction between osteoclast precursors

In our search for molecules involved in the process of osteoclast differentiation, we examined the surface phenotypes of the preosteoclast-like cells and osteoclast-like multinucleated cells (MNCs) formed in bone marrow cultures, using monoclonal antibodies recognizing different antigen molecules expressed on hematopoietic cells. Among these cell surface antigens, lymphocyte function-associated antigen-1 (LFA-1) and intercellular adhesion molecule-1 (ICAM-1) were highly expressed on mononuclear cells in the cultures for forming preosteoclast-like mononuclear cells. The double detection of these two antigen molecules with osteoclast-specific antigen and with calcitonin receptor, using a fluorescence-activated cell sorter or autoradiography technique, revealed that LFA-1 and ICAM-1 were expressed on the preosteoclasts. The expression of ICAM-1 was detected on both preosteoclasts and osteoclast-like MNCs, whereas the expression of LFA-1 was restricted to preosteoclasts. We designed a peptide with the sequence of the binding site of ICAM-1 against the ligand LFA-1. In the whole bone marrow culture system for forming osteoclast-like MNCs, a significant inhibition of MNC formation was observed by the addition of this peptide. These results strongly suggest the involvement of an LFA-1/ICAM-1-interaction in osteoclastogenesis.     

Angiogenesis in squamous cell carcinoma in situ and microinvasive carcinoma of the uterine cervix

OBJECTIVE: To evaluate angiogenesis in squamous cell carcinoma in situ (CIS) and microinvasive squamous cell carcinoma of the uterine cervix and to investigate the relations among angiogenesis, stromal inflammation, and depth of invasion. METHODS: Three groups of women were studied: 22 controls who had undergone hysterectomy for benign conditions; 18 with squamous cell CIS of the cervix who underwent cone biopsy, hysterectomy, or both; and 14 with microinvasive squamous cell carcinoma who underwent conization of the cervix and subsequent surgical management according to depth of invasion. All specimens were stained immunohistochemically for factor VIII-related antigen. Areas below the basement membrane with the highest angiogenic density were selected. The degree of stromal inflammatory reaction was assessed. Statistical analyses included Kruskal-Wallis, analyses of variance and covariance, Scheffe and Bonferroni-Dunn post hoc procedures, and Pearson correlation analysis. P < .05 was considered statistically significant. RESULTS: Microvessel counts per high-power field (x 400) of microinvasive squamous cell carcinoma of the cervix differed significantly from those of controls and squamous cell CIS (median 34.5 per high-power field, range 9-76 versus median 17, range 7-47, and median 19, range 8-39, respectively; P < .005). Microvessel counts per high-power field in squamous cell CIS did not differ significantly from those of controls (P = .91). Among patients with microinvasive squamous cell carcinoma of the cervix, no significant correlation was found between microvessel counts per high-power field and the depth of invasion (r = 0.19, P = .51). Stromal inflammatory reaction (graded 0-3) differed significantly among controls, squamous cell CIS, and microinvasive carcinoma (mean 0.40, 0.83, and 1.64, respectively; P < .005). CONCLUSIONS: Microinvasive squamous cell carcinoma of the uterine cervix is angiogenic, but depth of invasion is not associated with increased angiogenicity. Squamous cell CIS is not angiogenic.     

Microsatellite instability in squamous cell carcinoma of the head and neck

Genomic instability or microsatellite instability (MI) in simple repeated sequences was initially recognised in colonic carcinomas and subsequently in other tumours. MI has been associated with mutations in genes concerned with replication and DNA repair. We investigated 34 microsatellite markers in squamous cell carcinoma of the head and neck (SCCHN). Fifty-six tumours, were studied, of which 25 were investigated with ten or more microsatellite markers. In this study we consider two or more microsatellite alterations in a tumour to be diagnostic of MI. We demonstrated that 7/25 (28%) of the tumours had MI at two or more loci and three of these tumours exhibited evidence of 20 or more loci with MI. No correlations were found between MI and previous treatment, site, histological differentiation, positive nodes at pathology, a history of alcohol intake or survival. MI has been demonstrated in T1N0 stage tumours, indicating that these changes may occur early in the disease process. A negative correlation was found between MI and a history of smoking (P = 0.02). Two or more markers of MI were found in three of four non-smokers compared with one of 13 in the smoking group of patients, which suggests a novel mechanism of carcinogenesis in non-smokers.     

Basaloid squamous cell carcinoma of the esophagus: diagnosis and prognosis

BACKGROUND: Basaloid squamous cell carcinoma (BSCC) is a recently recognized, poorly differentiated variant of squamous cell carcinoma (SCC), which is located predominantly in the upper aerodigestive tract. METHODS: In this study, clinical and pathologic parameters of 17 BSCCs and 133 typical SCCs of the esophagus that underwent potentially curative resection (no distant metastases, no residual tumor) were compared. In addition, light microscopic, electron microscopic, and immunohistochemical features of BSCC were investigated, to determine whether this type of carcinoma could be differentiated from other poorly differentiated carcinomas of the esophagus. RESULTS: Light microscopic study showed that BSCC was composed of relatively small tumor cells, arranged in solid lobules with abundant comedo-type necrosis. BSCC was almost invariably accompanied by areas of concomitant typical SCC, foci of squamous cell differentiation, and/or severe squamous cell dysplasia or carcinoma in situ of the adjacent mucosa. Ultrastructurally, BSCC inconsistently showed features of squamous cell differentiation. Immunohistochemically, BSCC displayed poor reactivity for antibodies against wide-range cytokeratins and cytokeratin subtypes that are typical of squamous cell epithelia (cytokeratin 13 and cytokeratin 14). Infrequently, expression of Leu7, smooth muscle actin, and S-100 protein was found. In comparison with typical SCC, the characteristic features of BSCC were older patient age, higher proliferative activity (MIB-1 labelling index), and higher apoptotic indices. No differences were found with regard to pT classification, pN classification, tumor size, blood vessel invasion, lymphatic vessel invasion, neural invasion, or patient gender. Moreover, no differences in overall survival rates were found. CONCLUSIONS: BSCC is a distinct histopathologic variant of SCC, characterized by a poor degree of differentiation and high proliferative activity. However, after potentially curative resection, the prognosis of patients with BSCC of the esophagus does not differ from that of patients with typical SCC.     

bcl-2, p53 immunophenotypes and apoptosis in squamous cell carcinoma of the oesophagus

To establish baseline information on neopterin concentrations in livestock, companion and laboratory animals and identify the factors that may influence these concentrations, blood samples were taken from normal dairy cattle, horses, llamas, dogs, cats and rats of varying ages and sexes. In addition, neopterin concentrations in normal, adult equines were compared with those found in racing Thoroughbreds. There were no differences due to sex, sexual maturity, pregnancy, castration, or age. For all ages and sexes combined, mean neopterin concentrations were significantly lower in llamas (2.27+/-0.33 nmol litre(-1)) and rats (2.13+/-0.21 nmol litre(-1)) when compared with the other species tested. Racing Thoroughbreds demonstrated higher neopterin values than adult equines not in training (3.54+/-0.64 vs 3.13+/-1.02 nmol litre(-1)).     

p53 gene alternation in squamous cell carcinoma of the esophagus detected by PCR-cold SSCP analysis

Mutations of the p53 tumor suppressor gene play an important role in the development of common human malignancies. Previous reports revealed that the frequencies of p53 alternations in esophageal carcinoma varied from 26% to 87%. The clinical significance of p53 alternations is still disputed. In the present study, we used polymerase chain reaction--"cold" single-strand conformation polymorphism (PCR-"cold" SSCP)--to investigate p53 genetic alternations in 63 surgical specimens of esophageal squamous cell carcinoma (ESC). Our experiments showed that the optimum buffer temperature for "cold" SSCP analysis was 14 degrees C while the PCR products were around 200-300 bp in size. Among 63 tumorous samples, p53 alternations was detected in 47 tumors, or an incidence rate of 74.6%. For nontumorous mucosal samples, the incidence of p53 alternations was 55.5% (35/63 samples). Additionally, p53 alternations occurred most frequently at exon 6 (50.8%), followed by exon 7 (33.3%), exon 8 (17.5%) and exon 5 (12.7%). Multiple genetic alternations (> or = 2 exons) between p53 exons 5-8 in the same examined samples were found in 21 (33.3%) of 63 tumors, and in 8 (12.7%) of 63 nontumorous mucosal specimens. Our results further showed that p53 alternations did not correlate with age, depth of tumor invasion, lymph node metastasis, tumor stage, cell differentiation or lymphovascular invasion in ESC (P > 0.05). Moreover, the survival rate in patients with p53 alternations was similar to that in patients without p53 alternations (P > 0.05). In conclusion, PCR-"cold" SSCP is a rapid and sensitive method for identifying p53 genetic alternations. p53 genetic alternations occur with a relatively high incidence for ESC, but p53 abnormality has no impact on prognosis.     

Coexistence of endometrioid ovarian tumor and squamous cell carcinoma of the cervix

A case of the coexistence of the endometrioid ovary carcinoma and frank cervical carcinoma was shown. The diagnostic procedure, surgery and complementary therapy were described. On the basis of the follow-up of the patient it seams that the coexistence of these carcinomas neither accelerate the development of disease nor make worse the prognosis.