HMGA1a induces alternative splicing of estrogen receptor alpha in MCF-7 human breast cancer cells

The high-mobility group A protein 1a (HMGA1a) protein is known as an oncogene whose expression level in cancer tissue correlates with the malignant potential, and known as a component of senescence-related structures connecting it to tumor suppressor networks in fibroblasts. HMGA1 protein binds to DNA, but recent studies have shown it exerts novel functions through RNA-binding. Our previous studies have shown that sequence-specific RNA-binding of HMGA1a induces exon-skipping of Presenilin-2 exon 5 in sporadic Alzheimer disease. Here we show that HMGA1a induced exon-skipping of the estrogen receptor alpha (ERα) gene and increased ERα46 mRNA expression in MCF-7 breast cancer cells. An RNA-decoy of HMGA1a efficiently blocked this event and reduced ERα46 protein expression. Blockage of HMGA1a RNA-binding property consequently induced cell growth through reduced ERα46 expression in MCF-7 cells and increased sensitivity to tamoxifen in the tamoxifen-resistant cell line, MCF-7/TAMR1. Stable expression of an HMGA1a RNA-decoy in MCF-7 cells exhibited decreased ERα46 protein expression and increased estrogen-dependent tumor growth when these cells were implanted in nude mice. These results show HMGA1a is involved in alternative splicing of the ERα gene and related to estrogen-related growth as well as tamoxifen sensitivity in MCF-7 breast cancer cells.

HMGA1a Induces Alternative Splicing of the Estrogen Receptor-αlpha Gene by Trapping U1 snRNP to an Upstream Pseudo-5' Splice Site

Objectives: The high-mobility group A protein 1a (HMGA1a) protein is known as a transcription factor that binds to DNA, but recent studies have shown it exerts novel functions through RNA-binding. We were prompted to decipher the mechanism of HMGA1a-induced alternative splicing of the estrogen receptor alpha (ERα) that we recently reported would alter tamoxifen sensitivity in MCF-7 TAMR1 cells.

Methods: Endogenous expression of full length ERα66 and its isoform ERα46 were evaluated in MCF-7 breast cancer cells by transient expression of HMGA1a and an RNA decoy (2′-O-methylated RNA of the HMGA1a RNA-binding site) that binds to HMGA1a. RNA-binding of HMGA1a was checked by RNA-EMSA. In vitro splicing assay was performed to check the direct involvement of HMGA1a in splicing regulation. RNA-EMSA assay in the presence of purified U1 snRNP was performed with psoralen UV crosslinking to check complex formation of HMGA1a-U1 snRNP at the upstream pseudo-5′ splice site of exon 1.

Results: HMGA1a induced exon skipping of a shortened exon 1 of ERα in in vitro splicing assays that was blocked by the HMGA1a RNA decoy and sequence-specific RNA-binding was confirmed by RNA-EMSA. RNA-EMSA combined with psoralen UV crosslinking showed that HMGA1a trapped purified U1 snRNP at the upstream pseudo-5′ splice site.

Conclusions: Regulation of ERα alternative splicing by an HMGA1a-trapped U1 snRNP complex at the upstream 5′ splice site of exon 1 offers novel insight on 5′ splice site regulation by U1 snRNP as well as a promising target in breast cancer therapy where alternative splicing of ERα is involved.

Barbiturate Induction for the Prevention of Emergence Agitation after Pediatric Sevoflurane Anesthesia

OBJECTIVES

Emergence agitation (EA) is a common and troublesome problem in pediatric patients recovering from general anesthesia. The incidence of EA is reportedly higher after general anesthesia maintained with sevoflurane, a popular inhalational anesthetic agent for pediatric patients. We conducted this prospective, randomized, double-blind study to test the effect of an intravenous ultra-short-acting barbiturate, thiamylal, administered during induction of general anesthesia on the incidence and severity of EA in pediatric patients recovering from Sevoflurane anesthesia.

METHODS

Fifty-four pediatric patients (1 to 6 years of age) undergoing subumbilical surgeries were randomized into 2 groups. Patients received either intravenous thiamylal 5mg/kg (Group T) or inhalational Sevoflurane 5% (Group S) as an anesthetic induction agent. Following induction, general anesthesia was maintained with Sevoflurane and nitrous oxide (N2O) in both groups. To control the intra- and post-operative pain, caudal block or ilioinguinal/iliohypogastric block was performed. The incidence and severity of EA were evaluated by using the Modified Objective Pain Scale (MOPS: 0 to 6) at 15 and 30 min after arrival in the post-anesthesia care unit (PACU).

RESULTS

Fifteen minutes after arrival in the PACU, the incidence of EA in Group T (28%) was significantly lower than in Group S (64%; p = 0.023) and the MOPS in Group T (median 0, range 0 to 6) was significantly lower than in Group S (median 4, range 0 to 6; p = 0.005). The interval from discontinuation of Sevoflurane to emergence from anesthesia was not significantly different between the 2 groups.

CONCLUSIONS

Thiamylal induction reduced the incidence and severity of EA in pediatric patients immediately after Sevoflurane anesthesia.

PALETTE: A randomized, double-blind, phase III trial of pazopanib versus placebo in patients (pts) with soft-tissue sarcoma (STS) whose disease has progressed during or following prior chemotherapy—An EORTC STBSG Global Network Study (EORTC 62072)

LBA10002

Background: Pazopanib, a multi targeted angiogenesis inhibitor, has demonstrated single-agent activity in pts with advanced STS. The efficacy and safety of pazopanib versus placebo as second or later line treatment were evaluated in pts with metastatic STS in a multi-center, international, double-blind, placebo-controlled phase III trial. Methods: Pts ≥18 years of age with angiogenesis inhibitor-naïve, histologically proven, metastatic STS, who failed at least one anthracycline containing regimen, could enter the study. They should have ≥1 measurable baseline lesion (per RECIST v1.0), WHO PS 0-1, adequate bone marrow, coagulation, hepatic and renal function, no poorly controlled hypertension, no bleeding diathesis, and no CNS involvement. The study has been conducted by EORTC and GSK in collaboration with 72 sarcoma centers worldwide. Pts were randomized 2:1 to receive either pazopanib 800 mg once daily or placebo until tumor progression, unacceptable toxicity, death, or pt’s request. Results: A total of 369 randomized pts (246 pazopanib, 123 placebo), median age of 56 years, participated in the study (EORTC 45 %, other 55%). Median duration of follow-up at clinical cut-off date is 15 months. The primary endpoint of progression-free survival (PFS) per independent review is significantly prolonged with pazopanib (median: 20 vs 7 weeks; HR=0.31, 95% CI 0.24-0.40 ; P<0.0001). The interim analysis for overall survival shows a statistically non-significant improvement of pazopanib vs placebo (median: 11.9 vs 10.4 months, HR=0.83, 95% CI 0.62-1.09). Main on-therapy grade 3-4 toxicities in the pazopanib vs placebo arm respectively: fatigue (13%, 6%), hypertension (7%, nil), anorexia (6%, nil), and diarrhea (5%, 1%). Similarly, thromboembolic events (grade 3-5 ) (3%, 2%), LVEF drop of >15% (8%, 3%). Median relative dose intensity of pazopanib was 768 mg daily. Conclusions: Pazopanib is an active drug in anthracycline pretreated metastatic STS pts with an increase in median PFS of 13 weeks.

Stromal inactivation of BMPRII leads to colorectal epithelial overgrowth and polyp formation

Stromal-epithelial interactions play a central role in development and tumorigenesis. Bone morphogenetic protein (BMP) signaling in the intestine is involved in both of these processes. Inactivation of BMP pathway genes in the epithelium is known to cause intestinal polyposis. However, the role of the intestinal stroma in polyp initiation is incompletely understood. We observed that conditional inactivation of the BMP type II receptor (BMPRII) in the stroma leads to epithelial hyperplasia throughout the colon with increased epithelial cell proliferation. Mutant mice developed rectal bleeding and hamartomatous polyps in the colorectum. The polyps demonstrated increased proliferation of epithelial and mesenchymal cells in the mucosa with an expansion of the myofibroblast cell population. These results demonstrate that genetic mutations altering the BMP signaling pathway in the stromal microenvironment can lead to epithelial tumors in the colon.

Clear cell sarcoma of tendons and aponeuroses: An analysis of 75 cases

9572

Background: Clear cell sarcoma (CCS) of tendons and aponeuroses is a rare malignant tumor that occurs most commonly in the extremities of young adults. Because of the rarity of the disease (1% of all soft tissue sarcomas), most reports about CCS have dealt with a few cases during a long time period. We conducted a multi-institutional study of CCS to clarify the clinical findings and prognostic factors of CCS treated during the era of modern multidisciplinary treatment. Methods: The records of 75 consecutive patients with histologically confirmed CCS treated at the JMOG affiliated institutions between 1980 and 2004 (follow-up; average 44 months) were reviewed. There were 41 men and 34 women with an average age of 36 years (range, 10–71 years). 65 tumors were in the extremities (foot 22, hand 13, thigh 9, others 21) and 10 were in the trunk. The tumor size ranged from 1 to 11 cm (mean, 4 cm). 52 patients presented with localized disease (M0) and 23 with metastatic disease (M1). Results: Surgical excision of the primary tumor was performed in 71 patients (limb-sparing surgery; 56, amputation; 15). Microscopic surgical margin was negative in 60 and positive in 11. 56 patients received chemotherapy (30 with measurable disease) and 17 had radiotherapy. Local recurrence occurred in 16 patients and 48 patients developed metastasis. The 5-year overall survival rate was 47% (M0; 55%, M1; 20%). On univariate analysis, sex (p=0.02), size (p=0.001), depth (p=0.002), TNM stage (p=0.001), IRS group (p=0.001) and surgical margin (p=0.04) were prognostic factors. On multivariate analysis, size (p=0.02) remained to be a significant prognostic factor. Objective response to chemotherapy was observed in 8 (27%) patients. In the group of M0 patients, those who received adjuvant chemotherapy had better prognosis (5-year survival, 65%) than those without chemotherapy (5-year survival, 23%)(p=0.03). Conclusions: The results support the contention that early diagnosis and initial excision with negative surgical margin are essential for favorable outcome of CCS. The role of chemotherapy for CCS should be further investigated.

No significant financial relationships to disclose.

Extraskeletal mesenchymal chondrosarcoma: an imaging review of ten new patients

OBJECTIVE

Extraskeletal mesenchymal chondrosarcoma (EMC) is a rare soft-tissue tumor that most arises in young adults. Because of its rarity, few imaging studies have been reported to date. The purpose of this study was to elucidate the imaging features of this tumor.

DESIGN

We conducted a multi-institutional study in cooperation with five referral cancer centers in Japan. Imaging findings of ten new EMC cases, including conventional radiography, computed tomography (CT), and magnetic resonance imaging (MRI), performed at each institute, were reviewed along with clinical features.

PATIENTS

Ten patients with EMC, who had been treated at each hospital from 1990 to 2001, participated in this study.

RESULTS AND CONCLUSIONS

Soft-tissue masses with well-demarcated, dense and granular calcification were most frequently observed on plain radiographs and CT scans. T2-weighted MR images most clearly depicted a two-component structure composed of calcified and uncalcified areas, and enhanced MRI showed inhomogeneous enhancement in both areas. Although the sensitivity and specificity of these findings are unknown, they might be characteristic and have diagnostic value for this rare tumor.

A practical approach to the clinical diagnosis of Ewing's sarcoma/primitive neuroectodermal tumour and other small round cell tumours sharing EWS rearrangement using new fluorescence in situ hybridisation probes for EWSR1 on formalin fixed, paraffin wax embedded tissue

BACKGROUND

Over 90% of Ewing's sarcoma/primitive neuroectodermal tumour (ES/PNET) cases have the t(11;22) chromosomal rearrangement, which is also found in other small round cell tumours, including desmoplastic small round cell tumour (DSRCT) and clear cell sarcoma (CCS). Although this rearrangement can be analysed by fluorescence in situ hybridisation (FISH) using routinely formalin fixed, paraffin wax embedded (FFPE) tissues when fresh or frozen tissues are not available, a sensitive and convenient detection method is needed for routine clinical diagnosis.

AIMS

To investigate the usefulness of newly developed probes for detecting EWS rearrangement resulting from chromosomal translocations using FISH and FFPE tissue in the clinical diagnosis of ES/PNET, DSRCT, and CCS.

METHODS

Sixteen ES/PNETs, six DSRCTs, and six CCSs were studied. Three poorly differentiated synovial sarcomas, three alveolar rhabdomyosarcomas, and three neuroblastomas served as negative controls. Interphase FISH analysis was performed on FFPE tissue sections with a commercially available EWSR1 (22q12) dual colour, breakapart rearrangement probe.

RESULTS

One fused signal and one split signal of orange and green, demonstrating rearrangement of the EWS gene, was detected in 14 of 16 ES/PNETs, all six DRSCTs, and five of six CCSs, but not in the negative controls.

CONCLUSIONS

Interphase FISH using this newly developed probe is sensitive and specific for detecting the EWS gene on FFPE tissues and is of value in the routine clinical diagnosis of ES/PNET, DSRCT, and CCS.

A MALIGNANT PERIPHERAL NERVE-SHEATH TUMOUR RESPONDING TO CHEMOTHERAPY

Amalignant peripheral nerve-sheath tumour developed in the right S1 nerve root in a man aged 30 causing back pain and sciatica. CT and MRI revealed a destructive tumour of the sacrum invading the retroperitoneal space. The tumour was not resectable with an adequate margin. Chemotherapy, consisting of high-dose ifosfamide followed by a combination of vincristine, doxorubicin and cyclophosphamide, was given with success. Malignant peripheral nerve-sheath tumours are thought to respond weakly to chemotherapy, but the response in our patient was complete.

A malignant peripheral nerve-sheath tumour responding to chemotherapy

A malignant peripheral nerve-sheath tumour developed in the right S1 nerve root in a man aged 30 causing back pain and sciatica. CT and MRI revealed a destructive tumour of the sacrum invading the retroperitoneal space. The tumour was not resectable with an adequate margin. Chemotherapy, consisting of high-dose ifosfamide followed by a combination of vincristine, doxorubicin and cyclophosphamide, was given with success. Malignant peripheral nerve-sheath tumours are thought to respond weakly to chemotherapy, but the response in our patient was complete.

Low grade malignant peripheral nerve sheath tumour: varied cytological and histological patterns

BACKGROUND

A small number of malignant peripheral nerve sheath tumours (MPNSTs) are low grade, and the nature of these low grade tumours has never been systematically assessed.

AIMS

To describe the clinicopathological, immunohistochemical, and ultrastructural features of low grade MPNST and to discuss the main differential diagnoses.

METHODS

Four cases of low grade MPNST were studied, including one coexistent with neurofibromatosis type 1. The tumours were analysed with respect to nuclear atypia, cellularity, nuclear enlargement, hyperchromasia, mitotic rate, and necrosis. Immunohistochemistry was performed by standard techniques, and an ultrastructural study was performed on one tumour.

RESULTS

The ages of the patients ranged from 32 to 72 years (mean, 58). Two were male and two were female. Three tumours occurred in the deep tissue, including one in the retroperitoneum, and one was located in the dermal and subcutaneous tissue. The maximum diameters of the tumours ranged from 3.5 to 8.0 cm. Microscopically, all tumours showed moderate hypercellularity, an increased nuclear to cytoplasmic ratio, and hyperchromasia, but exhibited varied growth patterns, including those that were atypical neurofibroma-like, low grade fibromyxoid sarcoma-like, low grade epithelioid, and haemangiopericytoma-like. All tumours showed immunoreactivity for S-100 protein and vimentin.

CONCLUSIONS

These findings suggest that careful clinical and histological evaluation, along with S-100 protein immunostaining, are essential for the accurate diagnosis of low grade MPNST.

Prognostic relevance of rosette-like features in osteosarcoma

AIMS

To clarify the prognostic relevance of rosette-like features and other clinicopathological and immunohistochemical variables in patients with osteosarcoma.

METHODS

Clinicopathological and immunohistochemical variables were analysed in 131 patients with non-metastatic high grade conventional osteosarcoma, with particular attention to the prognostic impact of rosette-like features.

RESULTS

Rosette-like features were present in 18 (14%) cases. Rosette-like features were significantly associated with the osteoblastic subtype, numerous osteoclast-like giant cells, moderate pleomorphism, frequent haemangiopericytoma-like vascular patterns, epithelioid cytological features, positive immunoreactivity for epithelial membrane antigen and CD56, and negative staining for cytokeratin. In a multivariate analysis, rosette-like features (relative risk (RR), 3.8), a poor chemotherapy effect (RR, 2.9), and a tumour size of 10 cm or more (RR, 2.8) were identified as unfavourable prognostic factors.

CONCLUSIONS

Rosette-like features can easily be identified from routine histological slides and the relative risk in patients with non-metastatic, conventional osteosarcoma is as high as other well known prognostic factors, including large size and poor chemotherapy effect.

Osteosarcoma with cytokeratin expression: a clinicopathological study of six cases with an emphasis on differential diagnosis from metastatic cancer

AIMS

To clarify the clinicopathological profile of osteosarcomas showing an intensely positive immunoreaction for cytokeratin.

METHODS

Clinicopathological and immunohistochemical features were analysed in 131 patients with non-metastatic, conventional osteosarcoma, treated in Akita University and National Cancer Centre in Tokyo between 1972 and 1999.

RESULTS

Six patients (4.5%; mean age, 32 years; four men, two women) had osteosarcomas showing intense cytokeratin expression. Tumours were located on the long bones of the extremities in five patients and the ilium in one. Osteoid formations were found in biopsied specimens in all cases. Three tumours were classified as osteoblastic osteosarcoma, two as fibroblastic, and one as chondroblastic. In three tumours classified as the osteoblastic subtype, epithelioid features were prominent, and four tumours showed pronounced cellular pleomorphism. In contrast to the expression of cytokeratin, epithelial membrane antigen was negative in all cases. Surgery with a wide excisional margin was performed in six patients. Preoperative and postoperative chemotherapy was given to five of the six patients, but the effects of these agents were negligible. Three of the six patients developed lung metastases, whereas the other three patients have remained well with no evidence of local recurrence or distant metastasis.

CONCLUSIONS

Osteosarcoma with intense immunoreaction for cytokeratin was rare. The clinicopathological features were similar to those of patients with conventional osteosarcoma, except for a higher age, chemotherapy resistance, histological epithelioid features, and pleomorphism. This study indicates that osteoid formation and negative expression of epithelial membrane antigen are key features in the differentiation from metastatic carcinoma.

Prognostic significance of grading (MIB-1 system) in patients with myxoid liposarcoma

AIMS

To determine the relation between clinical outcome and tumour grade defined by a MIB-1 (Ki-67) score based grading system.

METHOD

The clinical and pathological features of 50 patients with myxoid liposarcoma were evaluated, and MIB-1 immunostaining was performed to grade these patients' tumours. Univariate and multivariate analyses were conducted to evaluate survival. Clinical follow up details were available for all patients (median, 46.5 months; range, 9-408).

RESULTS

Univariate analysis revealed that the tumour site (p < 0.05), round cell component content (p < 0.01), necrosis (p < 0.01), mitosis (p < 0.01), MIB-1 labelling index (p < 0.001), and tumour grade (p < 0.001) had a significant impact on overall survival. Multivariate analysis showed that, of the variables evaluated, the tumour grade defined by a MIB-1 score based grading system was the most significant adverse prognostic factor.

CONCLUSION

Tumour grade determined by the grading system using the MIB-1 score (MIB-1 system) is a very strong prognostic factor in patients with myxoid liposarcoma.

Germline p53 mutation in a patient with multiple primary cancers

We report a case of multiple primary cancers having a germline missense mutation of the p53 gene. The patient was a Japanese female and had a history of five different types of cancers. PCR/direct sequencing analysis revealed the presence of a nucleotide substitution, AGC (Ser) to AGG (Arg), at codon 106 of the p53 gene in DNA from non-cancerous breast tissue. This is the first case of germline p53 mutation at codon 106, and could contribute to establishing correlations between the types and locations of germline p53 mutations and their phenotypical consequences.

A multidisciplinary approach to the treatment of malignant pelvic bone tumors: results with eight consecutive patients

The prognosis for malignant pelvic bone tumors is worse than that for malignant bone tumors of the extremities because definitive surgery in the pelvis is often difficult to accomplish. The results for eight patients who were treated consecutively with a multidisciplinary approach, from 1990, were analyzed. The histologic diagnosis was osteosarcoma in five patients, chondrosarcoma in two, and Ewing's sarcoma in one. Five lesions arose in the ilium and three in the pubis. The extraosseous tumors decreased in size and/or were encapsulated as a result of preoperative chemotherapy in six patients, four of these achieving a wide surgical margin. With respect to tumor location and surgical margin, all five lesions in the ilium involved the sacrum, four of these being resected with an inadequate margin. The three lesions in the pubis were resected with an adequate margin. Local recurrence was observed in two patients who had been treated with an inappropriate margin. During the period between 18 and 57 months after the first operation, five patients were continuously free of disease and one was still alive but had lung metastases. Our results indicate that a patient's chances of definitive surgery may be enhanced by a multidisciplinary approach, although the management of sacroiliac involvement remains challenging.

Absence of germline CHK2 mutations in familial gastric cancer

Recently, the CHK2 gene was identified as being a candidate gene responsible for Li-Fraumeni syndrome (LFS). Gastric cancer is often clustered in families with LFS, so it is possible that germline CHK2 mutation is also present in familial gastric cancer (FGC). We therefore defined the genomic structure of the CHK2 gene, designed intronic primers, and searched for germline CHK2 mutations in 25 FGC cases by polymerase chain reaction-single strand conformational polymorphism analysis of the entire coding region. In all of the 25 cases, at least two siblings had histories of gastric cancer. There were no FGC cases that showed germline CHK2 mutations. Thus, it was indicated that germline CHK2 mutations do not contribute to the familial clustering of gastric cancer.

The human mucus protease inhibitor and its mutants are novel defensive compounds against infection with influenza A and Sendai viruses

Tryptase Clara, a trypsin-like protease localized exclusively in and secreted by Clara cells of the bronchial epithelium, is a prime host factor that processes viral envelope glycoproteins and determines the infectivity of influenza A and Sendai viruses (H. Kido, Y. Yokogoshi, K. Sakai, M. Tashiro, Y. Kishino, A. Fukutomi, and N. Katunuma, The Journal of Biological Chemistry, 1992, Vol. 267, pp. 13573-13579). We report here that human mucus protease inhibitor (MPI), a major inhibitor of granulocyte elastase in the lining fluid of the human respiratory tract, significantly inhibited induction of the infectivity of influenza A and Sendai viruses by tryptase Clara in vitro and multicycles of mouse-adapted influenza A virus replication in rat lungs in vivo. Recombinant MPI and the C- but not the N-terminal domain of MPI inhibited both the activity of tryptase Clara and the induction of virus infection by tryptase Clara. The 50% inhibitory concentrations of MPI and the C-terminal domain peptide (Pro50-Ala107) of MPI for tryptase Clara were 7.4 and 61.6 nM, respectively, with Sendai virus envelope glycoproteins as the substrate. Studies on deletion mutants of the C-terminal domain of MPI revealed that the minimal size of MPI required for the inhibition of tryptase Clara is the peptide Lys60-Ala107. Studies involving site-directed mutagenesis of the C-terminal domain of MPI indicated that the Leu72-Met73 site of MPI is the inhibitory site for tryptase Clara. Substitution of residue Leu72 with a basic amino acid significantly increased in the inhibitory activity of the C-terminal domain of MPI, but further substitution of residue Met73 with various amino acids in these mutants reduced the inhibitory activity. Since there is evidence suggesting that the concentration of MPI in respiratory fluid is insufficient for prevention of virus infection, the administration of MPI, the recombinant C-terminal domain of MPI, and their mutants, with residue Leu72 substituted with residues Arg72 and Lys72, may be useful for treatment of such pneumotropic virus infections.

Prognostic relevance of a histological grading system using MIB-1 for adult soft-tissue sarcoma

Several histological grading systems have been proposed and found as strong indicators of outcome in soft-tissue sarcomas. However, a putative independent prognostic influence of recently developed biological and molecular markers remains to be established. This study investigated the prognostic relevance of a histological grading system based on the assessment of proliferative activity in adult soft-tissue sarcomas of the extremities, trunk, head, and neck. Tissue blocks from 95 of 108 patients without distant metastases or regional lymph node involvement were available. Immunohistochemical staining for MIB-1 and p53 was done on paraffin-embedded sections. All clinicopathologic and immunohistochemical variables and patient survival were assessed using univariate and multivariate analyses. Variables included histological grading based on the modified Fédération Nationale des Centres de Lutte Contre le Cancer (FNCLCC) system using the MIB-1 score for the estimation of the proliferative potential of the tumors. Variables associated with overall survival were tumor site in the trunk, head and neck, mitosis count, necrosis, MIB-1 score, FNCLCC grade, modified FNCLCC grade using the MIB-1 score, and stage (all p values <0.05). In multivariate analysis, the modified grade proved to be the most significant predictor of shortened overall survival, in addition to tumor site in the trunk, head, and neck. Overexpression of p53 did not correlate with increased risk of tumor mortality. Using MIB-1 to replace mitosis counts in the FNCLCC system improves grading of soft-tissue sarcomas, and this in conjunction with other important factors appear to be more accurate prognostic factors for survival, and for patient selection in investigational adjuvant treatment trials.

Color tuning mechanism of human red and green visual pigments

We investigated the molecular mechanism of a rather large red shift of 31 nm in a human red pigment compared with a human green pigment. In this analysis, we paid special attention to the phenomenon of nonadditivity of spectral shifts due to substitution of the key amino acids (OH-bearing amino acids) and the phenomenon of cooperativity by which the spectral shifts due to substitution of the key amino acids in the protein environment of red pigment are about 1.5 times larger than that in the protein environment of green pigment. The analysis was made by using a model of three active sites on which the key amino acids are located and four effective sites by which the effect of the key amino acids is modified. As a result, we found that the interaction between the active sites that occurs through the repolarization of the chromophore induced by the key amino acid is essential for the nonadditivity phenomenon. We also found that the interaction between the active site and the effective site plays a major role in the cooperativity phenomenon. More directly, we say that the highly polarizable property of the chromophore is the origin of the rather large red shift in red pigment. Based on these analyses, we conclude that the interaction between the polarizable chromophore and the protein moiety has the capability of producing a significant spectral shift, at least 1000 cm-1, even by substitution of moderate polar residues of the OH-bearing amino acids.

Synovial sarcoma, histologically mimicking primitive neuroectodermal tumor/Ewing's sarcoma at distant sites

We report a case of synovial sarcoma (SS) showing unusual histology at distant sites. A 47-year-old man was aware of a tumor on the sole of his left foot. After preoperative chemotherapy with a diagnosis of SS, wide excision was performed. During postoperative chemotherapy, multiple tumorous lesions developed in the bone (including the whole spine) and both lungs. The patient died 1 year later. Histologically, the excised tumor of the foot showed a biphasic cellular pattern typical of SS, whereas at autopsy the bone and lung lesions were composed only of undifferentiated small round cells with cytoplasmic fibrillar processes. Homer-Wright rosettes were also observed. Immunohistochemically, 80% of the bone and lung tumor cells expressed MIC2 protein homogeneously. To clarify whether the bone and lung round cell tumors were metastatic lesions or second malignancies, especially primary primitive neuroectodermal tumor (PNET)/Ewing's sarcoma (ES), we performed reverse transcription-polymerase chain reaction (RT-PCR) analysis of tumor type-specific fusion gene transcripts. The SYT/SSX fusion transcript was identified in both the foot and lung lesions, whereas the EWS/FLI1 transcript was not detected in either lesion. Therefore, we concluded that the multiple bone and lung tumors were poorly differentiated metastatic tumors, which arose from the SS of the foot. We also conclude that the identification of chimeric fusion transcripts can be successfully applied to poorly differentiated sarcomas and will help in the differential diagnosis of tumors that cannot be distinguished by conventional morphological examinations. Also, it should be remembered that cytoplasmic staining for MIC2 protein may occur in sarcomas other than PNET/ES.

Pulmonary artery sarcoma diagnosed using intravascular ultrasound images

Primary and secondary malignant intravascular tumours of the pulmonary artery occur infrequently and the diagnosis is usually delayed as symptoms and findings from conventional examinations are non-specific. The case is presented of a patient with a pulmonary artery sarcoma, probably arising from ribs resected some years previously, in which intravascular ultrasound (IVUS) provided important diagnostic findings.

Intracortical osteoblastic osteosarcoma with oncogenic rickets

Intracortical osteosarcoma is the rarest variant of osteosarcoma, occurring within, and usually confined to, the cortical bone. Oncogenic osteomalacia, or rickets, is an unusual clinicopathologic entity in which vitamin D-resistant osteomalacia, or rickets, occurs in association with some tumors of soft tissue or bone. We present a case of oncogenic rickets associated with intracortical osteosarcoma of the tibia in a 9-year-old boy, whose roentgenographic abnormalities of rickets disappeared and pertinent laboratory data except for serum alkaline phosphatase became normal after surgical resection of the tumor. Histologically, the tumor was an osteosarcoma with a prominent osteoblastic pattern. An unusual microscopic feature was the presence of matrix mineralization showing rounded calcified structures (calcified spherules). Benign osteoblastic tumors, such as osteoid osteoma and osteoblastoma, must be considered in the differential diagnosis because of the relatively low cellular atypia and mitotic activity of this tumor. The infiltrating pattern with destruction or engulfment of normal bone is a major clue to the correct diagnosis of intracortical osteosarcoma. The co-existing radiographic changes of rickets were due to the intracortical osteosarcoma.

Ganglion cells in Ewing's sarcoma following chemotherapy: a case report

A case of Ewing's sarcoma of the bone, arising in the right radius of a 12-year-old girl, which showed unique histologic features after pre-operative treatment, is reported. The light microscopic features of a biopsy sample were those of a small round cell tumor showing positive immunoreaction with antibodies against the product of the MIC 2 gene (O13), neuron-specific enolase, neurofilament, and synaptophysin, but no morphological differentiation. The patient received combined intensive multi-drug chemotherapy and radiation before surgery. Examination of the surgical specimen showed that the tumor was less cellular than that in the biopsy specimen, and was composed mainly of loosely textured large cells mimicking ganglion cells, occasionally forming Homer-Wright rosettes. An immunohistochemical study revealed that neural differentiation was enhanced. Immunoreactivity for Leu-7 also became positive. Although the patient underwent postoperative chemotherapy, she died of multiple lung and bone metastases 30 months after the diagnosis. Autopsy showed that metastatic foci were made up of densely packed small round cells like those seen in the biopsy samples, but associated with prominent Homer-Wright rosettes. To the authors' knowledge, this is the first report of a tumor being replaced almost entirely by ganglion cells after pre-operative chemotherapy and radiotherapy.

[TNM classification of bone and soft tissue sarcomas]

TNM classification of bone and soft tissue sarcomas was published by UICC in 1987. Histological grading (G) is an important factor in this classification, but the criteria of G categories are not so clear. In addition, lymph node metastasis is very rare in bone and soft tissue sarcoma. Therefore, prognostic factors are limited to T, M and G categories. Since correlation between the stage (UICC) and the survival rate was not found in patients with osteosarcoma, TNM classification (UICC) has not been used widely in the field of orthopedic oncology. The Musculoskeletal Tumor Committee of the Japanese Orthopaedic Association proposed another TNM classification of osteosarcoma based on multivariate analysis. T1 is less than 15 cm and T2 is 15 cm or larger in maximal diameter. N and M are same with the UICC criteria. Serum alkaline phosphatase level (A) is included in this classification in which A0 is less than the normal value x2.5, and A1 is the normal value x2.5 or more. G categories are separated into two groups according to the mitotic rate in a high power field (x200); G1 is assigned to the tumor with 0-9/1 HPF and G2 is assigned to those with 10 or more/1 HPF. Reclassification of osteosar-coma by this modified TNM system indicated that there was a correlation between the survival rate and the stage.

[Improvement in function-preservation in radiotherapy for pediatric malignancies]

In radiotherapeutic management for pediatric tumors, we have to pay more attention to confinement of higher dose to the target volume than for adult tumors, in order that the risk of untoward normal tissue complications dose not increase, such as growth retardation. Two current approaches performing in our department to match this purpose are presented, namely, perioperative brachytherapy and fractionated stereotactic radiotherapy (F-SRT). In perioperative brachytherapy for bone and soft tissue sarcoma, plastic guide tubes for introducing radioactive sources are placed in the residual tumor bed or at the margins during the surgery, and patients are treated by high-dose-rate brachytherapy after surgery. Patients are not restricted in radioprotective area, and the overall treatment period is short enough. F-SRT is used either as the boost of conventional brain radiotherapy in primary brain neoplasms, or as hypofractionated F-SRT for control of metastatic brain tumors, with nearly perfect local control and maintenance of good quality of life. F-SRT is planned in 3-dimensional fashion from computed tomography images. Easily detachable, relocatable cast made for F-SRT is useful in pediatric patients.

Molecular basis of proteolytic activation of Sendai virus infection and the defensive compounds for infection

It has been proposed that the pathogenicity of Sendai virus is primarily determined by a host cellular protease(s) that activates viral infectivity by proteolytic cleavage of envelope fusion glycoproteins. We isolated a trypsin-like serine protease, tryptase Clara, localized in and secreted from Clara cells of the bronchial epithelium of rats. The enzyme specifically cleaved the precursor of fusion glycoprotein F0 of Sendai virus at residue Arg116 in the consensus cleavage motif, Gln(Glu)-X-Arg, resulting in the presentation of the membrane fusion domain in the amino-terminus of the F1 subunit. Administration of an antibody against tryptase Clara in the airway significantly inhibited the activation of progeny virus and multiple cycles of viral replication, thus reducing the mortality rate. These findings indicate that tryptase Clara in the airway is a primary determinant of Sendai virus infection and that proteolytic activation occurs extracellularly. We identified two cellular inhibitory compounds against tryptase Clara in bronchial lavage. One was a mucus protease inhibitor, a major serine protease inhibitor of granulocyte elastase in the lining fluids of the human respiratory tract, and the other was a pulmonary surfactant which may adsorb the enzyme, resulting in its inactivation. These compounds inhibited virus activation by tryptase Clara in vitro and in vivo, but did not themselves affect the hemagglutination and the infectivity of the virus. The functional domain of the mucus protease inhibitor against the enzyme, which is organized in two homologous N- and C-terminal domains, is located in the C-terminal. Administration of these compounds in the airway may be useful for preventing infection with Sendai virus.

Human mucus protease inhibitor in airway fluids is a potential defensive compound against infection with influenza A and Sendai viruses

Tryptase Clara, a trypsin-like protease localized exclusively in and secreted from Clara cells to the bronchial epithelium of rat, proteolytically activates the infectivity of influenza A virus [H. Kido, Y. Yokogoshi, K. Sakai, M. Tashiro, Y. Kishino, A. Fukutomi, and N. Katunuma (1992) J. Biol. Chem. 267, 13573-13579]. We report here that human mucus protease inhibitor (MPI), a major inhibitor of granulocyte elastase in the lining fluids of the human respiratory tract, significantly inhibited proteolytic activation of the infectivity of influenza A and Sendai viruses by tryptase Clara in vitro and multi-cycles of mouse-adapted influenza A virus replication in rat lungs in vitro. Recombinant MPI and the C- but not the N-terminal domain of the MPI inhibited both the proteolytic activity of tryptase Clara and the activation of virus infection. The 50% inhibitory concentrations of recombinant MPI and the C-terminal domain for tryptase Clara with Sendai virus envelope glycoprotein as substrate were 7.4 and 61.6 nM, respectively. These results indicate that MPI is a defensive compound against virus infection. Since there is evidence suggesting that concentrations of MPI in respiratory fluids are insufficient for prevention of virus infection, administration of MPI in the airway may be useful for treatment of these virus infections.

Comparison of Tc-99m pertechnetate with Tl-201 and Ga-67 scintigraphy of malignant soft-tissue tumors

Tc-99m pertechnetate scintigraphy was compared with Tl-201 chloride and Ga-67 citrate to evaluate the avidity of Tc-99m pertechtate for malignant soft-tissue tumors. Twenty-three patients with malignant soft-tissue tumors underwent scintigraphic studies. All 23 received Tc-99m and Tl-201, whereas 14 also were injected with Ga-67. In 21 (91%) of the 23 patients, Tc-99m accumulated extensively in the tumors. Tl-201 accumulated in 12 (52%) of the 23 tumors. Ga-67 accumulated in only 5 (36%) of the 14 tumors. The avidity of Tc-99m for myxoid tumors was markedly different from the other two agents. Tc-99m accumulated in all eight myxoid tumors, while neither Tl-201 or Ga-67 showed marked accumulation except for one patient with increased accumulation of Tl-201. This study shows that Tc-99m pertechnetate has the potential to localize malignant soft-tissue tumors and may be useful in the evaluation of these tumors.

Osteochondroma after total body irradiation in bone marrow transplant recipients: report of two cases

We present two cases of osteochondroma after total body irradiation in bone marrow recipients, the first in a 6-year-old boy with juvenile chronic myelogenous leukemia and the second in a 13-year-old boy with acute myelogenous leukemia. The patients developed multiple osteochondromas three years and seven years, respectively, after 12 Gy of total body irradiation. Neither had a family history of hereditary multiple osteochondromatosis. A review of the English literature revealed only one report describing five cases of osteochondroma after 12 Gy of total body irradiation in bone marrow transplant recipients. Osteochondroma should be considered as an additional adverse effect of total body irradiation.

Thallium-201 scintigraphy to assess effect of chemotherapy in osteosarcoma

Imaging results in patients with high-grade osteosarcoma of the extremities were reviewed to determine whether scintigraphic appearance correlated with histologic response to preoperative chemotherapy.

METHODS

Histologically, the percent tumor necrosis in specimens from 30 patients were classified into three grades: grade 1 = necrosis less than 60%, grade 2 = 60%-89% necrosis and grade 3 = diffuse necrosis greater than 90% based upon whole transverse sections. Scintigraphically, we analyzed 201TI uptake before and after preoperative chemotherapy. The changes in the tumor-to-background ratio were defined by an alteration ratio.

RESULTS

Of the 11 patients with a grade 1 response, the ratio showed -67.1% +/- 45.4% (mean +/- s.d.). Of the 9 patients with a grade 2 response, the ratio showed 37.9% +/- 29.9% of the 10 patients with a grade 3 response the ratio showed 105.5% +/- 12.4%. The ratios correlated well with the histologic grades (p < 0.0001; analysis of variance).

CONCLUSION

Thallium-201 scintigraphy accurately assesses the effect of chemotherapy on osteosarcoma.

Inhibitory effect of pulmonary surfactant on Sendai virus infection in rat lungs

Intranasal infection of rats with active (infectious) Sendai virus enhances secretion of tryptase Clara, a Sendai virus-activating protease, into the bronchial lumen by Clara cells of the bronchial epitheliums, and inversely suppresses secretion of pulmonary surfactant, an inhibitor of the protease, into the lumen [Kido H et al. (1993) FEBS Lett 322: 115-119]. A trypsin-resistant mutant, TR-2, showed similar effects, although its replication was restricted to a single cycle in the lungs. In contrast, neither nonactive (noninfectious) wild-type virus possessing receptor-binding activity and lacking envelope fusion activity nor UV-inactivated virus retaining receptor binding and envelope fusion activities altered the mode of secretions. These results indicate that viral replication is required for producing a condition in the bronchial lumen for proteolytic activation of progeny virus, thereby infection is extended to a fatal pneumonia. On the other hand, intranasal administration of infected rats with pulmonary surfactant suppressed activation of progeny virus and pathological changes in the lungs, suggesting a therapeutic use of pulmonary surfactant for influenza pneumonia.

Primary malignant melanoma (clear cell sarcoma) of bone: report of a case arising in the ulna

BACKGROUND

To the authors' knowledge, there has been no previous report of primary malignant melanoma of bone.

METHODS

A 33-year-old woman presented with a tumorous lesion in the olecranon of the right ulna. The histologic diagnosis was malignant melanoma with close similarity to clear cell sarcoma. To exclude the possibility of malignant melanoma metastatic to the bone, clinical investigations including gallium 67-citrate scintigraphy, brain, chest, and abdominal computed tomography, and upper and lower gastrointestinal endoscopic examinations were performed. Conventional histopathologic, immunohistochemical, and electron microscopic studies were also performed.

RESULTS

Clinical investigations showed no lesion suggestive of a primary melanoma other than that in the right ulna. Histologically, the tumor was comprised of polygonal or fusiform cells with clear or granular cytoplasm and vesicular nuclei containing one or two prominent nucleoli. The features were similar to those of clear cell sarcoma (malignant melanoma of soft parts). Fontana preparations and immunohistochemical staining for S-100 protein and HMB-45 (melanoma specific antigen) also revealed that the tumor cells had the characteristics of malignant melanoma. The patient has remained alive and well for more than 5 years after the initial treatment.

CONCLUSIONS

The clinicopathologic findings in this case strongly suggested that the lesion was a primary malignant melanoma of bone. Therefore, this is the first report to indicate that malignant melanoma and related diseases can occur even in bone tissue.

Immunochemical characteristics and localization on cells of protective antigen (PAg) prepared from Leptospira interrogans serovar lai

Immuno-electron microscopic methods revealed that the protective antigen (PAg) of Leptospira interrogans serovar lai exists on the outer envelope sheathing the leptospiral cell body. PAg lost its protective activity after treatment by hydrolysis with 2 M formic acid at 100 C for 2 hr, or oxidation with periodate at 4 C for 40 hr. The antigenic oligosaccharide fraction was further purified from the hydrolyzed PAg by immunoaffinity column coupled with protective monoclonal antibody, LW2, and by gel filtration of HPLC. The antigenic oligosaccharide fraction contained two unknown sugars and 4-O-methylmannose (molar ratio 3:5:1). These findings suggested that these sugars are components of an antigenic determinant contributing to the protective immunity against serovar lai infection.

Histamine release induced by human natriuretic peptide from rat peritoneal mast cells

We have been interested in the effects of some popular peptides on tracheal smooth muscle. Previously, we reported that atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP) and C-type natriuretic peptide (CNP) had dose-dependent relaxant effects on guinea pig tracheal smooth muscle. In this study, we compared the effects of ANP, BNP and CNP on histamine release from rat peritoneal mast cells. ANP and BNP were more potent than CNP, dose-dependently increasing histamine release at a concentration of 10(-7) M or higher. CNP induced histamine release at a concentration of 10(-6) M or higher. Extracellular calcium inhibited the histamine release induced by all 3 peptides. In conclusion, the effects of these 3 peptides in rat peritoneal mast cells demonstrated adverse reactions for respiratory diseases, although our previous results showed that these peptides caused relaxation of guinea pig tracheal smooth muscle. We should note that the drugs have different actions in each organ.

Cellular proteases involved in the pathogenicity of enveloped animal viruses, human immunodeficiency virus, influenza virus A and Sendai virus

In enveloped viruses, post-translational proteolytic activation is a critical step for the fusion activity and thus for the infectivity of the virus. In addition to the membrane receptors for the viruses, proteolytic activation is indispensable for effective virus spread in the infected host and it is a prime determinant for pathogenicity. Here we described the host cellular processing proteases, tryptase Clara and tryptase TL2, which proteolytically activate the infectivity of influenza A and Sendai viruses in the respiratory tract and HIV-1 in human CD4+ T cells, respectively. A novel trypsin-like protease, designated tryptase Clara, was purified from rat lung. The enzyme is localized in Clara cells of the bronchial epithelium and is secreted into the airway lumen. The enzyme specifically recognizes the consensus cleavage motif Gln(Glu)-X-Arg of influenza A and Sendai viruses and proteolytically activates the envelope fusion glycoproteins of the progeny viruses extracellularly in the airway lumen. Human mucus protease inhibitor and pulmonary surfactant in airway fluid inhibited the proteolytic activation of these viruses and also suppressed multiple cycles of viral replication in vitro. These results suggest that an imbalance between the amount of tryptase Clara and that of endogenous inhibitors in airway fluid is a prime determinant for pneumopathogenicity of the viruses. Therefore supplementing an endogenous inhibitor at therapeutic doses may protect against virus infection. In HIV-1 infection, binding of the gp120 envelope glycoprotein to the CD4 receptor is not sufficient in itself to allow virus entry, and an additional component(s) in the membrane is required for cell infection as a cofactor. We isolated a serine protease named tryptase TL2, in the membrane of CD4+ lymphocytes, which specifically binds to the V3 loop of HIV-1 gp120 as a cofactor. After binding, tryptase TL2 proteolytically processed gp120 into two protein species of 70 and 50 kDa and the cleavage was suppressed by a neutralizing antibody against the V3 loop. The amino acids that constitute the cleavage sites in the V3 loop of almost all HIV isolates are variable, but they are restricted to those which are susceptible to chymotryptic and/or tryptic enzyme. The multi-substrate specificity of tryptase TL2, which has tryptic and chymotryptic specificities, may correspond tot he variability of the V3 loop. The selective cleavage of the V3 loop by tryptase TL2 may lead to a conformational change of gp120, resulting in the dissociation of gp120 from gp41, exposing the fusogenic domain of the transmembrane protein gp41 following virus-host cell fusion.

FUS/TLS-CHOP chimeric transcripts in liposarcoma tissues

Myxoid liposarcoma and malignant fibrous histiocytoma (MFH) are common soft tissue sarcomas of adulthood. Histopathologically they often show intratumor heterogeneity. In some cases, differential diagnosis of liposarcoma and MFH is difficult. It has been reported that myxoid liposarcomas are characterized by chromosomal translocation t (12; 16) (q13; p11), and that this results in two types (type I and type II) of FUS/TLS-CHOP fusion transcripts. In this study, the FUS/TLS-CHOP chimeric transcripts in seven malignant soft tissue tumors of Asian patients were analyzed by reverse transcription-polymerase chain reaction, DNA blot hybridization and nucleotide sequencing. One myxoid liposarcoma and two round cell liposarcomas possessed a chimeric transcript whose fusion point was the same as that of the type I fusion transcript reported previously for myxoid liposarcoma. We were thus able to detect the type I FUS/TLS-CHOP fusion transcript in clinical specimens of liposarcoma from Asian patients, including the first examples of round cell liposarcoma. These results suggest that the detection of FUS/TLS-CHOP chimeric transcripts or chimeric genes can be used as a diagnostic tool for the pathological diagnosis of liposarcomas.

Role of technetium-99m pertechnetate scintigraphy in the management of extra-abdominal fibromatosis

The purpose of this study was to investigate technetium-99m pertechnetate (Tc-99m) as a tumor-scanning agent in patients with extra-abdominal fibromatosis, and to establish the sensitivity of this type of scintigraphy. Eleven patients with extra-abdominal fibromatosis were studied: all but one having postsurgical recurrences. Of the 11 patients, diagnosed histologically, 5 underwent repeated Tc-99m scintigraphic follow-up examinations. The injected 370 MBq Tc-99m gave us an early scintigram within 10 min and a delayed one 2 h later. For adequate comparison, the region of interest (ROI) of the scintigram was placed over the tumor. The tumor-to-background (T/BG) count ratio was computed. Extra-abdominal fibromatoses, even recurrences, were demonstrated scintigraphically in both the early and the delayed phase, in all 11 patients. The average T/BG ratio was 2.11 in the early scintigram and 2.15 in the delayed one. The sensitivity and the specificity were both 100%. Tc-99m scintigraphy has proved useful in detecting extra-abdominal fibromatoses and in the follow-up of patients.

Extraskeletal osteosarcoma: a clinicopathologic study of four cases

Four cases of extraskeletal osteosarcoma which were treated at the National Cancer Center Hospital have been reviewed. There were three males and one female. The ages of the patients were 32, 48, 48 and 59 years. Three patients had a solitary tumor located in the lower leg, thigh or postirradiated abdominal wall. The remaining patient had multiple tumors in the ipsilateral thigh and buttock. The predominant histologic subtype was osteoblastic in two cases, chondroblastic in one and malignant fibrous histiocytoma-like in one. Only one patient with a subcutaneous tumor was free of disease 16 years after a wide local excision without chemotherapy. The other three patients, two having undergone inadequate initial surgery, and one with multiple tumors, developed pulmonary metastases within 24 months of their initial surgical treatment. All of them died of the pulmonary metastases eight, 36 and 63 months after their initial treatment. Postoperative intensive chemotherapy was given to two patients. Although both had developed metastases to the lung, they received resection of the metastases combined with additional chemotherapy, surviving for more than 24 months after the occurrence of their first metastases.

Pulmonary resection for metastatic soft tissue sarcomas

The therapeutic results of pulmonary resection for metastatic soft tissue sarcomas were analyzed. From 1970 to 1992, 23 patients (15 male and 8 female) underwent 40 pulmonary resections for metastatic soft tissue sarcomas. Nine (39%) patients had multiple thoracotomies for recurrences (range, 2-6). The 5-year actuarial overall survival was 32% (median, 28 months). Statistical analysis showed that age, gender, location of primary tumor, histology, site of pulmonary metastasis, tumor doubling time, or chemotherapy did not impact on survival. Significant prognostic factors associated with improved survival (p < 0.05) included a disease-free interval, and completeness and extent of the initial pulmonary resection. Patients with disease-free intervals > or = 12 months survived longer (5-year survival, 48.5%) than patients with disease-free intervals < 12 months (12%). Patients who could be rendered free of disease at their initial thoracotomy, without extended chest-wall resection, achieved a better outcome (5-year survival, 44%) than the others (5-year survival, 0%).

Histamine release induced by pituitary adenylate cyclase activating polypeptide from rat peritoneal mast cells

Pituitary adenylate cyclase activating polypeptide 38 (PACAP 38) and its fragments PACAP 27, PACAP 16-38, PACAP 28-38, PACAP 31-38 were compared for their histamine releasing effects on rat peritoneal mast cells. PACAP 38 and PACAP 16-38 were the most active peptides, followed by PACAP 27. PACAP 38 and PACAP 16-38 dose-dependently increased histamine release at a concentration of 1 x 10(-8) mol/l or higher, and these releasing activities were more than 100 times more potent than that of substance P. Extracellular calcium inhibited the substance P-induced histamine release. In contrast, PACAP 38- and PACAP 27-induced histamine releases were hardly inhibited by extracellular calcium.

Nuclear immunoreaction of p53 protein in soft tissue sarcomas. A possible prognostic factor

BACKGROUND

Tumor suppressor gene p53, located on the short arm of chromosome 17, frequently mutates in various types of cancers and plays a critical role in the multiple stages of carcinogenesis. However, there is little information about the clinicopathologic significance of alterations of the p53 gene in soft tissue sarcomas (STS).

METHODS

Because it is known that nuclear accumulation of p53 protein correlates closely with the presence of mutations in the p53 gene, immunohistochemical detection of this protein was performed. A polyclonal antibody (RSP-53) raised against synthetic human p53 peptide was used to detect nuclear accumulation of the protein. Pathologic specimens of 96 patients with STS were collected from the surgical pathology files of the National Cancer Center Hospital and examined.

RESULTS

Nuclear accumulation of p53 protein was detected in 31 (32.3%) patients. The percentage of patients with a positive immunoreaction was high in patients with malignant schwannoma (100%), rhabdomyosarcoma (71.4%), and synovial sarcoma (50.0%), whereas it was low in patients with liposarcoma (13.6%) and 0% in those with fibrosarcoma. It was closely associated with the histologic grade of malignancy (grade 1, 12.0%; grade 2, 30.8%; grade 3, 44.4%) and the patient's age (younger than 40 years, 46.9%; 40 years of age or older, 25.0%). Both overall and metastasis-free survival rates were significantly lower for patients with a nuclear p53 immunoreaction than for those without it.

CONCLUSIONS

The nuclear p53 immunoreaction is considered a marker of tumor aggressiveness and appears to be a useful prognostic factor for STS.