Diminished neutralizing activity against the XBB1.5 strain in 55.9% of individuals post 6 months COVID-19 mRNA booster vaccination: insights from a pseudovirus assay on 1,353 participants in the Fukushima vaccination community survey, Japan

This study investigates the neutralizing activity against the XBB1.5 variant and the ancestral strain in a population post-bivalent vaccination using a pseudo virus assay validated with authentic virus assay. While bivalent booster vaccination and past infections enhanced neutralization against the XBB 1.5 strain, individuals with comorbidities showed reduced responses. The study suggests the need for continuous vaccine updates to address emerging SARS-CoV-2 variants and highlights the importance of monitoring real-world immune responses.

Potent neutralizing broad-spectrum antibody against SARS-CoV-2 generated from dual-antigen-specific B cells from convalescents

Several antibody therapeutics have been developed against SARS-CoV-2; however, they have attenuated neutralizing ability against variants. In this study, we generated multiple broadly neutralizing antibodies from B cells of convalescents, by using two types of receptor-binding domains, Wuhan strain and the Gamma variant as bait. From 172 antibodies generated, six antibodies neutralized all strains prior to the Omicron variant, and the five antibodies were able to neutralize some of the Omicron sub-strains. Structural analysis showed that these antibodies have a variety of characteristic binding modes, such as ACE2 mimicry. We subjected a representative antibody to the hamster infection model after introduction of the N297A modification, and observed a dose-dependent reduction of the lung viral titer, even at a dose of 2 mg/kg. These results demonstrated that our antibodies have certain antiviral activity as therapeutics, and highlighted the importance of initial cell-screening strategy for the efficient development of therapeutic antibodies.

Slow-Growing Large Irritation Fibroma of the Anterior Hard Palate: A Case Report Using Immunohistochemical Analysis

Irritation fibromas are recognized as fibrous lesions, usually reactive hyperplasias; however, the mechanism of enlargement is unclear. This paper reports on an abnormally large irritation fibroma of extremely gradual growth. The immunohistochemical features (CD34, α-SMA, vimentin, Ki-67, and TGF-α) of this irritation fibroma are presented to distinguish reactive hyperplasia from other true fibrous neoplasm diseases. In the only previous study, it was reported that the expression of TGF-α might be associated with the development of oral fibromas. Therefore, we investigated the relationship between this exceptionally-large fibrous lesion of extremely slow growth and the immunohistochemical reactivity of TGF-α, finding that, in contrast to the previous study, TGF-α was not expressed. This is the first study to evaluate the enlargement mechanism of such a large irritation fibroma using the approach of immunohistochemical analysis, and it indicates that such analysis can help elucidate the diverse causes and enlargement mechanisms of irritation fibromas.

NVP-TAE226, a potent dual FAK/IGF-IR kinase inhibitor, prevents breast cancer metastasis in vivo

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Background: Focal Adhesion Kinase (FAK) and Insulin-like Growth Factor-1 Receptor (IGF-IR) kinase are attractive anti-cancer drug targets because they are both drivers of tumor cell proliferation, migration, and survival. Although virtually every cell type expresses FAK, it is generally overexpressed in tumor cells. FAK levels are greatest in highly metastatic tumors. A selective FAK inhibitor would be expected to halt or kill invasive tumor cells, and potentially interfere with normal cell migration (e.g. endothelial cells). IGF-IR function is required for tumor cell survival, but dispensable for survival of normal cells. Therefore, a dual inhibitor of both kinases may selectively block the growth, migration, and survival of FAK- and IGF-IR- expressing tumor cells compared to proliferating and migrating normal cells. Methods: NVP-TAE226, a novel small molecule developed as an inhibitor of FAK, was evaluated in kinase enzymatic assays, cell-based kinase assays and 4T1 metastatic breast carcinoma in vivo model. Results: NVP-TAE226 inhibits FAK with low nanomolar IC50 values in a purified kinase enzymatic assay. In cell-based kinase assays, FAK and IGF-IR kinase were inhibited with an IC50 range of 100 to 300 nM compared to the other kinases tested which were >10-fold less sensitive. Oral administration of NVP-TAE226 inhibited 4T1 murine breast tumor growth and metastasis to the lung in a dose-dependent manner. The compound was well tolerated in mice as determined by measuring changes in body weight. The highest dose of 100 mg/kg, qd, 5x/week showed T/C value of 18%. Inhibition of FAK autophosphorylation at Y397 and Akt phosphorylation at Serine473 was observed in a dose-dependent manner in 4T1 breast carcinoma. Conclusions: NVP-TAE226 represents a novel class of selective and small molecule kinase inhibitors that have potential clinical applications with a potent in vivo activity.

[Table: see text]

Anti-cancer activity of NVP-TAE226, a potent dual FAK/IGF-IR kinase inhibitor, against pancreatic carcinoma

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Background: Focal adhesion kinase (FAK) is a non-receptor cytoplasmic tyrosine kinase that regulates multiple cell functions. Elevated expression levels of FAK have been detected in various tumor samples and are closely correlated with invasive potential. Activation of integrins and the growth factor receptors result in FAK autophosphorylation at Y397 and the presentation of suitable binding sites for proteins containing either SH2 or phosphotyrosine binding domains. Recent evidences suggest that FAK plays important roles in cancer cell proliferation and survival. IGF-IR function is required for tumor cell survival, but dispensable for survival of normal cells. Therefore, a dual inhibitor of both kinases may selectively block the growth, migration, and survival of FAK- and IGF-IR- expressing tumor cells compared to proliferating and migrating normal cells. Methods: In this study, anti-cancer activity of NVP-TAE226 that is identified as a potent and selective FAK inhibitor was evaluated in cancer cell lines panel and MIA PaCa-2 pancreatic carcinoma in vivo model. Results: Mean GI50 value of NVP-TAE226 against 37 cancer cell lines was 0.76 μmole/L. Inhibition of cancer cell proliferation was not affected by expression of P-glycoprotein, suggesting that NVP-TAE226 is not served as a substrate of P-glycoprotein. Oral administration of NVP-TAE226 efficiently inhibited MIA PaCa-2 human pancreatic tumor growth at all doses tested. Tumor stasis was observed at a dose of 30 mg/kg, qd for 7×/week and tumor regression was observed at a dose of 100 mg/kg, qd for 5×/week. All animals tolerated NVP-TAE226 treatment up to 100 mg/kg, 5×/wk, qd, po for 2 weeks with no body weight loss. Inhibition of downstream signaling such as phosphorylation of Akt at Serine473 was accompanied by inhibition of FAK phosphorylation in human pancreatic carcinoma cell lines. Conclusions: NVP-TAE226 is a novel class of selective and small molecule kinase inhibitors with a potent in vivo activity and potential therapeutic application.

No significant financial relationships to disclose.

EGF and beta1 integrin convergently regulate migration of A431 carcinoma cell through MAP kinase activation

We found that the convergently epidermal growth factor (EGF)-induced signal and the collagen-induced signal activate mitogen-activated protein kinase (MAPK), which induces migration. We examined the signaling mechanisms of EGF-induced cell migration on collagen using the A431 carcinoma cell. EGF (10 ng/ml) induced migration on collagen, but inhibited proliferation. Using a MAPK cascade inhibitor, PD98059, it was shown that EGF-induced migration on collagen was mediated by MAPK whereas EGF-induced migration on fibronectin and vitronectin was not. PD98059 also showed that activation of MAPK induced by EGF enhanced the adhesiveness of A431 cells to collagen. By Western blotting analysis, the kinetics of MAPK phosphorylation induced by EGF and collagen was examined separately, and convergently. First of all, EGF without collagen caused transient MAPK phosphorylation. Collagen without EGF caused MAPK to be immediately and transiently dephosphorylated, and rephosphorylated followed by sustained hyperphosphorylation. EGF together with collagen caused an immediate, and sustained, hyperphosphorylation. These facts suggest that the transient MAPK dephosphorylation induced by collagen is required for migration in order to maintain an appropriate level of sustained phosphorylation. Furthermore, we found that adhesion of A431 cells to collagen was blocked by the anti-beta1 integrin antibody or by the mixed antibodies composed of anti-alpha1, -alpha2, and -alpha3 antibodies, indicating that collagen-induced MAPK phosphorylation was mediated through alpha1beta1, alpha2beta1, and alpha3beta1 integrins.

Tumour necrosis factor-alpha provokes upregulation of alpha2beta1 and alpha5beta1 integrins, and cell migration in OST osteosarcoma cells

OST cells enhance the induction of matrix metalloproteinase (MMP)-9 by tumour necrosis factor (TNF)-alpha and the corresponding metastasis to lungs in vivo (Kawashima et al., 1994). We focused on the adhesive and migratory properties of OST cells, and investigated the expression of integrins in OST cells stimulated by TNFalpha in vitro. OST cells potentiated not only adhesion to the extracellular matrix (ECM) but also the migration on ECM. On competitive reverse transcription-polymerase chain reaction (RT-PCR) analyses, the amounts of alpha2 (4.9-fold), alpha5 (1.2-fold) and alpha(v) (4.9-fold) were upregulated by TNFalpha at the transcriptional level. Alpha-5 showed a slight increase by flow cytometry; however, alpha2 and alphav integrins remained unchanged at the protein level. Immunofluorescence study disclosed integrins of alpha2beta1 and alpha5beta1 were much clustered at cell processes by TNFalpha stimulation, probably related to increased cell adhesion and migration. Therefore, the upregulation of alpha2beta1 and alpha5beta1 integrins seems to contribute to tumour invasion and metastatic potential.

Migratory phenotypes of HSC-3 squamous carcinoma cell line induced by EGF and PMA: relevance to migration of loosening of adhesion and vinculin-associated focal contacts with prominent filopodia

Cell migration is involved in carcinoma cell invasion and wound healing. We examined motogenic cytokines that potentiated migration of human HSC-3 carcinoma cells. To assess migratory activity, modified Boyden chambers were used. Among a variety of potential motogenic cytokines, epidermal growth factor (EGF) enhanced migration of HSC-3 cells both on collagen and fibronectin. Phorbol myristate acetate (PMA) also enhanced migration. Inhibitors of protein kinase C completely inhibited PMA-induced migration, but only partly inhibited EGF-induced migration. Protein kinase A was also involved in the EGF-induced signaling pathway for migration. Although the signaling pathways were independent, and the cell shape on collagen was different from that on fibronectin, migratory cells stimulated by EGF or PMA showed common morphology on different ligands. The cells were polygonal or round in shape and the loss of long cytoplasmic extensions was noted. Migratory HSC-3 cells stimulated by EGF or PMA became less adhesive to collagen and fibronectin. Since both EGF- and PMA-stimulated migration did not require de novo protein synthesis, the signaling pathways possibly lead to assembly and disassembly of an actin cytoskeleton. Immunofluorescence for vinculin was concentrated into focal contacts in EGF- and PMA-stimulated HSC-3 cells, whereas the fluorescence signal was hardly detected in non-stimulated cells. Talin and beta1 integrin were immunolocalized at focal contacts in non-stimulated cells, and it remained unchanged in stimulated cells. Numerous filopodia visualized with actin immunofluorescence were formed around stimulated HSC-3 cells, whereas filopodia were short and sparse around elongated cytoplasms in non-stimulated cells. Thus, shortening of cytoplasmic extensions with numerous filopodia, loosening of adhesion, and vinculin-associated focal contacts were regarded as migratory phenotypes.

Na(+)-coupled transport of L-carnitine via high-affinity carnitine transporter OCTN2 and its subcellular localization in kidney

The mechanism of Na(+)-dependent transport of L-carnitine via the carnitine/organic cation transporter OCTN2 and the subcellular localization of OCTN2 in kidney were studied. Using plasma membrane vesicles prepared from HEK293 cells that were stably transfected with human OCTN2, transport of L-carnitine via human OCTN2 was characterized. Uptake of L-[(3)H]carnitine by the OCTN2-expressing membrane vesicles was significantly increased in the presence of an inwardly directed Na(+) gradient, with an overshoot, while such transient uphill transport was not observed in membrane vesicles from cells that were mock transfected with expression vector pcDNA3 alone. The uptake of L-[(3)H]carnitine was specifically dependent on Na(+) and the osmolarity effect showed that Na(+) significantly influenced the transport rather than the binding. Changes of inorganic anions in the extravesicular medium and of membrane potential by valinomycin altered the initial uptake activity of L-carnitine by OCTN2. In addition, the fluxes of L-carnitine and Na(+) were coupled with 1:1 stoichiometry. Accordingly, it was clarified that Na(+) is coupled with flux of L-carnitine and the flux is an electrogenic process. Furthermore, OCTN2 was localized on the apical membrane of renal tubular epithelial cells. These results clarified that OCTN2 is important for the concentrative reabsorption of L-carnitine after glomerular filtration in the kidney.

Small molecular mass inhibitor of growth of MDCK cells derived from pig spinal cord

We have discovered cell growth inhibitory activity in a salt extract of pig spinal cords. The growth inhibitory factor was purified by gel-filtration, ion-exchange and high performance liquid chromatography. Incubation of MDCK cells with the inhibitor arrested their locomotion within half an hour, suppressed their proliferation, and caused them to become round. The round cells that were still attached to the culture plate were alive. Upon removal of the inhibitor these cells flattened out and resumed locomotion and proliferation. The inhibitor was 100 times less effective on CHO-K1 cells. The reversible effects of the inhibitor on MDCK cells and its little effects on CHO-K1 cells indicate that the inhibitory activity is not due to a non-specific toxic mechanism. The inhibitor was both heat-stable and resistant to several chemical treatments, including proteases. Its behavior upon ion exchange chromatography suggested that it was positively charged at neutral pH, whilst its molecular mass was estimated to be 350 or larger by gel-filtration FPLC analysis. The inhibitory fraction reacted extensively with fluorescamine, suggesting that the inhibitory factor has amine groups, which are a possible candidate for its positive charges. Since spermine and spermidine, unlike the inhibitor in the present study, irreversibly inhibited the growth of the MDCK cells, the inhibitory activity in the present study is thus not due to contamination by these polyamines. Our experiments also support that the inhibitor is not a peptide.

Effect of fatty acid Esters on permeation of ketoprofen through hairless rat skin

Twelve medium to long chain fatty acid Esters (Esters), the total number of carbon atoms of which ranged from 17 to 34, were used to study the effect of the vehicle on the permeation of ketoprofen, and the effect was compared with the case of indomethacin. The solubility of ketoprofen was higher in Esters with a smaller number of carbon atoms. The permeation rate of ketoprofen from the Ester suspension through excised hairless rat skin was proportional to its solubility in the suspension, which was the same in the case of indomethacin. The diffusion constant and partition coefficient were calculated using the computer program MULTI(FILT). The diffusion constant decreased with increasing number of carbon atoms, and the partition coefficient was increased with increasing number of carbon atoms, in both cases of ketoprofen and indomethacin. Esters also penetrated the skin with the concentration of about 10 mg/g, independent of the number of carbon atoms. The Esters in the skin increase the diffusion rate of the drugs, especially in the case of Esters with a small number of carbon atoms. Also the drug solubility in the skin was improved, although the effect was similar for the range of Esters investigated in the present study. Then the permeation rate of ketoprofen and indomethacin increased.

Sarcomatoid hepatocellular-carcinoma showing rhabdomyoblastic differentiation in the adult cirrhotic liver

An unusual case of a massive liver tumour composed of rhabdomyosarcoma with a small focus of hepatocellular carcinoma in a 52-year-old man is presented. He had hepatitis B virus (HBV) surface antigen in his serum. Macroscopically, a large tumour with satellite nodules occupied the right lobe of the cirrhotic liver. Microscopically, the tumours were composed of small and short spindle-shaped undifferentiated cells, mixed with desmin-positive round rhabdomyoblasts and elongated striated muscle cells, strongly suggestive of rhabdomyosarcoma of the liver. Elevated levels of alpha-fetoprotein in the serum led us to examine the liver tumour closely in multiple sections, which disclosed a hepatocellular carcinoma component measuring 2 cm in diameter within the massive tumour. Immunohistochemically, the hepatocellular carcinoma cells were alpha-fetoprotein positive. There was neither a tumour capsule, nor distinct demarcation, and cytokeratin-positive clusters of undifferentiated cells were intermingled with the hepatocellular carcinoma and rhabdomyosarcoma at the border. The invading tumour outside the liver and metastatic tumours were pure rhabdomyosarcomas. It is suggested that the present case should be diagnosed as rhabdomyosarcoma transformed from hepatocellular carcinoma.

Association of vascular endothelial growth factor expression with angiogenesis and lymph node metastasis in nasopharyngeal carcinoma

OBJECTIVE

Recent experimental evidence indicates that angiogenesis affects tumor growth and metastasis. Vascular endothelial growth factor (VEGF) is considered to be an important regulator of tumor angiogenesis. The present study was designed to examine the role of VEGF on angiogenesis and lymph node metastasis in primary nasopharyngeal carcinomas (NPCs).

STUDY DESIGN

Formalin-fixed paraffin-embedded biopsy specimens were obtained from 29 primary NPCs that consisted of 22 differentiated nonkeratinizing carcinomas and seven undifferentiated carcinomas.

METHODS

Microvessels were highlighted by staining endothelial cells with von Willebrand factor (VWF) using immunohistochemical techniques, and were counted (per x 400 field) in the most active area of angiogenesis on light microscopy. The expression of VEGF was also studied with immunohistochemistry. Positive ratio for VEGF was graded on a scale of 1 and 2. Scale 1 represents patients with less than the mean value of the positive ratio, and scale 2 represents patients with more than the corresponding value.

RESULTS

There was a significant correlation between increased microvessel count and the progression of regional lymph node involvement. The microvessel counts and the progression of N factor were significantly higher in scale 2 patients than in scale 1 patients.

CONCLUSION

These results suggest that VEGF plays an important role in lymph node metastasis through induction of angiogenesis in NPCs.

[A case of small cell carcinoma of the stomach with multiple liver and lung metastases successfully treated by combined chemotherapy with cisplatin and etoposide]

We experienced a case of small cell carcinoma of the stomach in which chemotherapy had been markedly effective. A 54-year-old man was admitted to our hospital complaining of hematemesis. Gastric endoscopy showed a type 2 tumor at the lesser curvature of the cardia of the remnant stomach. Total gastrectomy, splenectomy and D2 lymph node dissection were performed. Histopathologically, the tumor was diagnosed as a small cell carcinoma with findings of t 2 n 1 in stage II, and conclusive curability was A. A month after the operation, CT-scan revealed multiple liver and lung metastases, so the patient was treated by combined chemotherapy with cisplatin and etoposide called PVP for three courses every four weeks for small cell lung cancer, which resulted in remarkable reduction of metastases (96% in the liver and 81% in the lung). This result suggests that PVP chemotherapy is effective in the treatment of small cell carcinoma of the stomach as well as the lung.

In vitro antitumor activities of new synthetic bistetrahydrofuran derivatives as analogs of Annonaceous acetogenins

We investigated the in vitro antitumor activities toward mouse and human cell lines of optically active synthetic bistetrahydrofuran (bis-THF) derivatives as analogs of Annonaceous acetogenins, which contain bis-THF, long unbranched alkyl chains, hydroxyl groups, and an alpha, beta-unsaturated gamma-lactone. These bis-THF derivatives were synthesized in a stereocontrolled manner, and have several modified structures at the alkyl side chains. We found that: 1) the unsaturated gamma-lactone contributes to high potency in combination with the other less-functionalized alkyl chain, 2) the same absolute configuration of the bis-THF skeleton as that of the natural products produces more potent activity than the counterpart, 3) the alkyl chains and hydroxyl groups are crucial for exhibiting antitumor activity, 4) hydroxyl groups adjacent to the bis-THF skeleton may be replaced by amino or acylamino groups.

Possible involvement of differential splicing in regulation of the activity of Arabidopsis ANP1 that is related to mitogen-activated protein kinase kinase kinases (MAPKKKs)

Three types of Arabidopsis cDNA (cANP1, cANP2 and cANP3) have been isolated that encode putative protein kinases, designated ANP1, ANP2 and ANP3. These kinases exhibit a high degree of homology to NPK1, a tobacco protein that is a member of the family of mitogen-activated protein kinase kinase kinases (MAPKKKs), which appears to function in the proliferation of tobacco cells. The predicted amino acid sequences of the kinase domains in the amino-terminal halves of the ANPs were more than 80% identical to that of NPK1, while the kinase-unrelated regions in the carboxy-terminal halves exhibited relatively low homology. Two species of cANP1 were identified, ANP1L cDNA (cANP1L) and ANP1S cDNA (cANP1S), which were derived from a single ANP1 gene: the former had an intron-like sequence in the coding region for the kinase-unrelated region, while the latter did not include such an intron-like sequence. cANP1L encoded a putative protein with both kinase and kinase-unrelated domains, resembling NPK1, whereas cANP1S encoded only the amino-terminal kinase domain because the intron-like sequence was absent, with resulting elimination of most of the kinase-unrelated region. Genetic analysis with mutant yeast cells showed that over-expression of cANP1L or of cANP1S activated the mating pheromone-responsive signal pathway which is mediated by a MAP kinase cascade. Moreover, the extent of such activation by cANP1S was greater than that by cANP1L. These results predict that differential splicing of the intron-like sequence in the ANP1 transcript might be at least one of the molecular mechanisms involved in the generation of active ANP1 protein kinase.

Exfoliative cytology of metastatic chordoma appearing in the sputum. A case report

BACKGROUND

Chordoma that arises along the spinal axis metastasizes to the lung on occasion. Chordoma has been reported to have characteristic cytologic features in fine needle aspiration cytology in primary and metastatic foci.

CASE

A 76-year-old female had a tumor on the buttock and tumors in the lung. Exfoliative cytology of the sputum showed cohesive, epithelioid clusters composed of pale-stained, broad cytoplasm with a lacelike pattern, minimal nuclear atypism with anisonucleosis and characteristic mucoid substances.

CONCLUSION

Cytopathologists should be aware of the possibility of metastatic chordoma when epithelioid tumor cell clusters with benign-looking features embedded in a mucoid substance are detected in aspiration cytology or sputum.

Primary lipoma of the diaphragm

Lipoma of the diaphragm is an extremely rare entity. A case of this disease is herein reported, together with the review of the literature. The patient described was a 70-year-old male, who was admitted to our hospital with an abnormal shadow on his chest X-ray film. The primary tumor, located above the left hemidiaphragm, was successfully resected by video-assisted thoracic surgery, and the final diagnosis of lipoma originating in the diaphragm was made.

Integrin distribution in gastric carcinoma: association of beta 3 and beta 5 integrins with tumor invasiveness

Immunolocalization of a variety of integrins using monoclonal antibodies against beta 3, beta 5, alpha 3 beta 1 and alpha 6, and polyclonal antibodies against vitronectin receptor (alpha v beta 3) and beta 1 were investigated on PLP-fixed paraffin sections of 19 cases of advanced gastric carcinomas. The beta 5 integrin, which pairs only with the alpha v subunit, was positive in seven cases (37%), and was associated closely with scirrhous invasion (P < 0.05). beta 5 was positive chiefly in the cytoplasm of carcinoma cells and infrequently in cell membranes. beta 3, which is another subunit pairing with alpha v, was positive in six cases (32%), and tended to be associated with scirrhous invasion (P < 0.01). beta 3 was also located chiefly in the cytoplasm. Five of the seven beta 5-positive cases showed coexpression of beta 3. Polyclonal antibodies to alpha v beta 3 also showed a significant difference among the amounts of stroma (P < 0.05). Anti-beta 1 antibodies showed clear positivity in many cases (89%). Of the beta 1 integrins, alpha 3 beta 1 was positive in a few cases (26%) without any preferential pattern, and laminin receptor subunit alpha 6 stained on cell membranes of neoplastic epithelia in many cases of carcinoma (89%) except for mucinous carcinoma These distinctive patterns of integrin positivity indicate a close association of beta 5 and beta 3 expression with scirrhous invasion in gastric carcinoma.

Induction of carcinoma cell migration on vitronectin by NF-kappa B-dependent gene expression

Integrin alpha v beta 5 promotes FG carcinoma cell adhesion to vitronectin yet requires protein kinase C (PKC) activation for migration on this ligand. Here we report that this PKC-dependent cell motility event requires NF-kappaB-dependent transcription. Specifically, a component within nuclear extracts prepared from PKC-stimulated FG cells exhibited a significant increase in binding activity to a synthetic oligonucleotide containing a consensus kappa B sequence. These nuclear DNA-binding complexes were shown to be comprised of p65 and p50 NF-kappaB/rel family members and appeared functionally active because they promoted transcription of a reporter construct containing a kappa B site. The NF-kappa B activation event was directly linked to the alpha v beta 5 motility response because the NF-kappa B-binding oligonucleotide, when introduced into FG cells, inhibited cell migration on vitronectin but not on collagen and had no effect on cell adhesion to either ligand. These results suggest that the detected DNA-binding complexes interact with kappa B transcriptional elements to regulate gene expression required for alpha v beta 5-dependent cell motility on vitronectin.

Inhibitory effects of adhesion oligopeptides on the invasion of squamous carcinoma cells with special reference to implication of alpha v integrins

We studied invasion-related adhesion events in vitro using three squamous carcinoma cell lines (HSC-3), poorly differentiated type; OSC-19, well-differentiated type; and KB cells, undifferentiated type). An in vitro invasion assay through matrigel in the transwell chamber revealed that HSC-3 cells were most invasive, OSC-19 cells moderately invasive and KB cells least invasive. Inhibition assay of invasion using synthetic peptides RGD, RGDV, RGDS, RGDT, IKVAV and YIGSR, showed that invasion of the three cell lines was significantly inhibited by RGDV. There were other peptides that inhibited invasion significantly including IKVAV for HSC-3, and RGDS and YIGSR for OSC-19. HSC-3 cells and OSC-19 cells adhered to fibronectin, laminin, vitronectin, and type IV collagen, and KB cells did not adhere to laminin but did to fibronectin, vitronectin and collagen type IV. Pretreatment of cells with RGDV peptide in the attachment assay reduced the ability of these cells to bind to vitronectin and fibronectin more efficiently than pretreatment with RGDS. Anti-alpha v antibodies inhibited adhesion of HSC-3, OSC-19 and KB cells to vitronectin, but anti-beta 1 antibodies did not inhibit adhesion. Immunofluorescent microscopic examinations showed that all cell lines were positive for anti-beta 5 and anti-alpha v antibodies, and only HSC-3 cells were positive for anti-beta 3 antibody. alpha 5 beta 1 was not clearly demonstrated in any of the cell lines. RGDV was the most effective inhibitor of squamous cell carcinoma invasion among the synthetic oligopeptides used in this experiment, and it is suggested that it affects alpha v beta 3- and/or alpha v beta 5-mediated carcinoma cell invasion.

Pleomorphic adenoma of parotid gland with cystic degeneration

Pleomorphic adenoma is the most common tumour to arise in the parotid gland. Diagnosis becomes difficult when such a tumour undergoes degeneration and presents with unusual findings. This can lead to erroneous decisions concerning treatment. We present two patients with pleomorphic adenoma of the parotid gland with cystic degeneration, describe the pathological findings and discuss some pitfalls in diagnosis and treatment. Both patients recovered uneventfully after surgery.

Immunohistologic distribution of basement membrane in oral squamous cell carcinoma

The distribution pattern of the basement membrane (BM) around tumor cells was determined in 72 oral squamous cell carcinomas by immunohistochemical staining with antibodies against human type IV collagen, laminin, and heparan sulfate proteoglycan. An intact continuous BM was found in 29 cases, whereas partial or widespread loss of the BM was detected in the other 43 cases (59.7%). Statistical analysis showed that the degree of BM loss was correlated with the degree of differentiation of tumor cells, but not with tumor size, and, most significantly, with the mode of cancer invasion and the incidence of lymph node metastasis. Carcinoma with a well-defined tumor-stromal boundary generally expressed an intact continuous BM. In contrast, the majority of diffusely invasive carcinomas lacked a continuous BM. Carcinomas with a widespread loss of BM structures showed a high frequency of regional lymph node metastasis (16 of 18 cases, 88.9%).

Immunohistochemical detection of breast specific antigens and cytokeratins in metastatic breast carcinoma in the liver

The present study was performed to evaluate the diagnostic reliability of antibodies to breast carcinoma-specific antigen and antibodies to cytokeratin catalogue in a metastatic hepatic lesion. Immunohistochemical examinations using antibodies to gross cystic disease fluid protein-15 (GCDFP-15), BCA-225 (a glycoprotein secreted by T47D breast carcinoma cell line) and BRST-5 (a glycoprotein identified in SK-BR-7 breast carcinoma cell line), anti-cytokeratin monoclonal antibodies of MA904, AE3, CAM5.2, PKK1 and cytokeratin 19, and polyclonal anti-keratin antibodies were done. These were on 15 cases of primary breast carcinoma, eight cases of metastatic breast carcinoma in the liver, five cases of cholangiocarcinoma, eight cases of hepatocellular carcinoma and 11 cases of metastatic adenocarcinoma of another primary tumor in the liver. Results showed that GCDFP-15 antigen was most reliable: it was 100% positive in both primary and metastatic breast carcinomas unrelated to histological subtypes, and 100% negative in primary or other metastatic carcinomas in the liver. BCA-225 antigen was detected in high amounts in breast carcinomas (100%, 23/23), but it was positive in cholangiocarcinomas (80%, 4/5) and another metastatic carcinoma in the liver (64%, 7/11). BRST-5 was specifically positive in breast carcinomas but the positivity was low (13%, 3/23). Cytokeratin 19 and keratin were useful to discriminate hepatocellular carcinomas (0%, 0/8) from breast carcinomas (87%, 20/23; 96%, 22/23), but they were also positive in cholangiocarcinomas (100%, 5/5) and other metastatic carcinomas in the liver (91%, 10/11).(ABSTRACT TRUNCATED AT 250 WORDS)

The expression of invasive behavior of differentiated squamous carcinoma cell line evaluated by an in vitro invasion model

In order to elucidate the factors contributory to the expression of invasiveness of oral squamous cell carcinoma, we conducted biochemical and morphological comparisons of well differentiated squamous carcinoma cell line OSC-19 (oral squamous cell carcinoma) and undifferentiated carcinoma cell line KB, both cultured on 3T3 cell-embedded collagen gel (in vitro invasion model). OSC-19 cells invaded 3T3 cell-embedded collagen gel, while KB cells and OSC-19 cells on 3T3 cell-free gel matrix were less invasive. Cultured OSC-19 cells were characterized by lower proliferating activity, lower secretion of laminin and higher secretion of fibronectin than those of KB cells. Although the basement membrane with deposition of laminin and type IV collagen was formed, it was discontinuous at the invasion front. Gelatin zymography and western blotting showed matrix metalloproteinases (MMP), i.e., 72 kDa gelatinase (MMP-2) and 92 kDa gelatinase (MMP-9). Gelatinolytic activity was assayed, and was higher in OSC-19 cells than in KB cells or OSC-19 cells of the 3T3 cell-free model. By immunohistochemical analysis, MMP-2-positive cells were found scattered in both cell lines without any preferential localization, and the positivity for MMP-9 was localized in the invasion front of OSC-19 cells. These results strongly suggest that the invasiveness of squamous cell carcinoma is well correlated with cell-matrix adhesion by fibronectin and with focal elaboration of metalloproteinases, especially MMP-9, which play a major role in degrading the extracellular matrix components.

Differential diagnosis of pleomorphic adenoma by immunohistochemical means

Immunohistochemical study of major salivary gland tumours was performed on 60 pleomorphic adenomas, five basal cell adenomas and 10 adenoid cystic carcinomas to determine the diagnostic value of each antigen. Immunoreactivity examined were intermediate filaments (keratin, vimentin, desmin and glial fibrillary acidic protein [GFAP]) and related substances (actin, S-100 protein and secretory component). In pleomorphic adenomas, there was positive immunoreactivity for GFAP which was not observed in normal tissue or other neoplastic tissues. Immunoreactivity of GFAP was closely related to myxomatous and early chondromatous differentiation in pleomorphic adenoma. It is considered that GFAP immunoreactivity should be assessed in the occasional differential diagnostic dilemma of pleomorphic adenoma versus adenoid cystic carcinoma and basal cell adenoma, because of its ability to show potential and definite myxochondromatous differentiation.

Microfilamentous type VI collagen in the hyalinized stroma of the hypertrophied ligamentum flavum

Thickened ligamenta flava obtained from 14 patients with spinal canal stenosis were examined with special reference to type VI collagen. The characteristic histological finding in the thickened area was rupture or normal elastic fibre meshwork with resultant fibrosis which usually appeared hyaline. Using an immunohistological method, collagen types VI, I and III were found to be present in the hyaline matrix. Ultrastructural study revealed many microfilamentous structures of type VI collagen admixed in loosely packed, banded collagen fibres. With differential salt precipitation of pepsin-extracted collagen the existence of type VI collagen was confirmed by SDS-polyacrylamide gel electrophoresis analysis and Western blotting analysis using anti-type VI collagen antibody. Quantification of type VI collagen in pepsin-extracted crude collagen samples by an inhibition enzyme-linked immunosorbent assay showed an increasing amount of type VI collagen in the thickened ligamenta flava compared to the normal ligaments. Thus, increase of type VI collagen is the main contribution to the thickening of the ligamentum flavum. This may represent an adaptational and reparative process associated with disruption of elastic fibres.

Malignant melanoma arising in a dermoid cyst of the ovary

Autopsy findings of primary malignant melanoma arising in an ovarian dermoid cyst in an 86-year-old woman are presented. The right ovary was replaced by a dermoid cyst, 14 x 9 x 9 cm in size, in which several nodular tumors with diameters less than 3.2 cm were localized. They comprised diffusely proliferating anaplastic cells with prominent nucleoli. Some of them contained melanin pigments in the cytoplasm. The tumor cells were positive for S-100 protein and ultrastructurally showed melanosomes. In addition, several benign pigmented lesions resembling dermal nevus, pigmented schwannoma, or cellular blue nevus were present in the dermoid cyst, one of which contained a malignant melanomatous component. Histologic transition between benign and malignant components and the presence of another small focus of atypical melanocytes in the benign lesion suggested that the malignant melanoma arose in close association with the previously existing benign pigmented lesions in the dermoid cyst.

Malignant melanocytic schwannoma of the nasopharynx

A rare case of malignant melanocytic schwannoma in the nasopharynx is presented. Light microscopy showed proliferation of spindle-shaped tumor cells with mitoses. The essential histological hallmark was melanin deposition. Electron-microscopic examination confirmed the schwannian differentiation of the tumor cells. The patient has remained well without evidence of metastasis or local recurrence of the tumor 18 months after the excision of the neoplasm.

'Atypical adenomatous hyperplasia' in liver cirrhosis: low-grade hepatocellular carcinoma or borderline lesion?

Adenomatous hyperplasia, defined as a sizable parenchymal nodule in cirrhosis, was examined morphologically. Ninety-seven nodules of adenomatous hyperplasia were obtained from 47 cirrhotic livers and were divided into 'ordinary' (44 nodules) and 'atypical' (53 nodules) types. The former consisted of hepatocytes similar to those of the surrounding liver, and showed regularly distributed portal tracts. The latter type was composed of hepatocytes showing nuclear atypia, relative to the surrounding liver, and showed irregular or sparse portal tracts. Atypical nodules were histologically heterogeneous, possessing areas of normo-trabecular, compact, pseudoglandular and/or scirrhous patterns. Several cytological changes, such as clear cell change, small or large cell change and fatty change, were intermingled variably within a given nodule. Atypical nodules showed expansive and/or replacing growth into the surrounding liver. Atypical hepatocytes also infiltrated into the fibrous septa and portal tracts. Foci of overt hepatocellular carcinoma were found in 11 of the 53 atypical nodules. These findings suggest that ordinary adenomatous hyperplasia may be a large-sized regenerative nodule, while atypical adenomatous hyperplasia may be a hepatocellular neoplasm, a peculiar form of low-grade hepatocellular carcinoma or borderline lesion, in which overt hepatocellular carcinoma is likely to evolve through multiple steps.

Left ventriculotomy of the heart: tissue repair and localization of collagen types I, II, III, IV, V, VI and fibronectin

The reparative process following left ventriculotomy was investigated immunohistochemically using anti-type I, II, III, IV, V and VI collagen antibodies, and anti-fibronectin antibody. Wound healing began with proliferation of young fibroblasts positive for type I, III and V collagens at the wound margin; vascular granulation tissue then grew into the injured myocardium followed by deposition of fibrous components immunoreactive with type I and III. At 30 days after operation when almost the entire thickness of the myocardium at the wound was replaced by fibrosing granulation tissue, a small cluster of adipocytes appeared around capillaries at the wound margin. The granulation tissue was gradually replaced by the adipose tissue with establishment of a fibrous union at the subendocardium by 90 days. In addition to type I and III collagens, type VI collagen was detected in a fine fibrillary pattern along thick collagen fibre bundles in the fibrous tissue and around the adipocytes. Fibronectin was distributed diffusely in the granulation tissue and gradually decreased with increase of the fibrous components. These results indicate that the ventriculotomy was finally repaired in the form of a fibrous scar, particularly in the endocardium. There was marked infiltration of adipose tissue in the damaged myocardium. Presumably type VI collagen, as well as type I and type III collagens, plays an important role in wound union.

The role of fibronectin in the development of experimental amyloidosis. Evidence of immunohistochemical codistribution and binding property with serum amyloid protein A

Azocasein-induced amyloid A (AA) amyloidosis in CBA/K1Jms mice was investigated to elucidate a preference of serum amyloid A (SAA) deposition in the spleen. By indirect immunofluorescence using anti-SAA/AA antibodies the initial deposition of SAA/AA was recognized in the marginal zone of spleen at 20 days after azocasein injection. Indirect immunofluorescence using anti-fibronectin antibodies also showed meshwork positivity in the corresponding area more intensely than that in controls. Immunoelectron microscopy using anti-SAA/AA revealed the presence of positively stained flocculent materials on cell surfaces of macrophages in the marginal area in addition to amyloid fibril. The tissue fibronectin rapidly increased in the spleen and maintained 10 times more than that of controls until the 20th day. Binding assay of SAA on frozen sections revealed the presence of SAA-binding substances in the perifollicular area. Affinity chromatographic assay showed fibronectin have a binding capacity to SAA1 and SAA2. By binding assay on the microtiter plate, SAA had more affinity to fibronectin than those of heparan sulfate, collagen type I, or serum amyloid P component. These results indicate that fibronectin plays an important role in the development of amyloidosis by working as a linking protein between SAA and the cell surface of macrophages.

Leiomyosarcoma of the thyroid gland. A case report with a comparative study of five cases of anaplastic carcinoma

We report on a case of leiomyosarcoma of the thyroid with ultrastructural features and expression of intermediate filament proteins different from that of anaplastic carcinomas. Histologic examination of multiple sections showed that they were leiomyosarcomatous, and neither epithelial features nor giant cell configurations were found. Electron microscopic examination showed microfilament bundles with dense patches and discontinuous basal lamina. Desmin, vimentin, and actin were positive for tumor cells, and cytokeratin, thyroglobulin, and calcitonin were negative. In contrast, the anaplastic carcinoma cases did not contain microfilament bundles with dense patches in their tumor cells. There were no desmin-positive or cytokeratin-negative tumor cells. We concluded that this case was a primary leiomyosarcoma, presumably derived from the smooth muscle cell of the vascular wall.

Immunohistochemical studies on the tissue localization of collagen types I, III, IV, V and VI in schwannomas. Correlation with ultrastructural features of the extracellular matrix

The distinctive tissue localization of collagen types in typical schwannomas with Antoni type A and B areas was demonstrated immunohistochemically using affinity-purified antibodies against types I, III, IV, V and VI collagen and comparative ultrastructural studies were made on the extracellular matrix components. Antoni type A tissue, which was composed of tightly packed spindle cells with long cytoplasmic processes surrounded by a continuous basement membrane and a few fibrillar components of the extracellular matrix, was almost exclusively immunoreactive for type IV collagen, presumably representing the basement membrane. Verocay bodies, which are organoid structures of Antoni type A tissue, had a variety of more abundant extracellular fibrous components, such as banded collagen fibrils, fibrous long-spacing fibrils and microfibrils. These were positive for type I and III, as well as type IV collagen. In Antoni type B areas, where two types to tumor cells designated Schwann cell-like and fibroblast-like were scattered in large amounts of amorphous extracellular matrix containing microfibrils and thick banded collagen fibrils, type VI collagen as well as types I, III and IV collagen were consistently detected. Type V collagen was localized in dense fibrous tissue areas and around blood vessels. These findings indicate that the differently organized cellular patterns of schwannomas, identified as Antoni types A and B, are characterized not only by the ultrastructural features of the extracellular matrix, but also by the distinctive collagen types produced by neoplastic Schwann cells.

Hepatocellular carcinoma arising in the abdominal cavity. An autopsy case of ectopic liver origin

An unusual case of extrahepatic disseminating hepatocellular carcinoma in a 64-year-old man is reported. The initial symptom was abdominal fullness and progressive ascites. Alpha-fetoprotein in the serum was 117,000 ng/ml. Exploratory laparotomy disclosed dissemination of tumor nodules throughout the abdominal cavity without any other possible primary tumor. CT scan, ultrasonography and hepatic angiography were unable to detect any tumor lesion in the liver. The final histologic diagnosis was hepatocellular carcinoma, although at first epithelioid mesothelioma was suspected. The present case of hepatocellular carcinoma was thought to have possibly developed from ectopic liver on the peritoneum.

Malignant fibrous histiocytoma of the liver: a case report and review of the literature

A case of primary sarcomatous tumor of the liver in a 61-yr-old man is reported. The tumor, which measured 8.5 X 8 X 8 cm, was located in the right lobe of the liver and consisted of spindle cells in a storiform pattern intermingled with bizarre giant cells. Immunohistochemically, most tumor cells expressed vimentin. Cytoplasmic immunoreactivity with alpha 1-antitrypsin and lysozyme was documented in the giant cells. Ultrastructurally, cells with fibroblastic and histiocytic features were present. The morphological and immunohistochemical findings justify the conclusion that the tumor should be classified as a malignant fibrous histiocytoma. Reported cases of hepatic malignant fibrous histiocytoma were reviewed and compared with similar tumors observed in other body sites.

Endocrine differentiation of gastric adenocarcinoma. The prevalence as evaluated by immunoreactive chromogranin A and its biologic significance

The prevalence of endocrine differentiation of conventional gastric adenocarcinoma was evaluated on the 212 cases (including 62 mucosal carcinomas) of consecutively resected stomach for adenocarcinoma in our hospital using anti-chromogranin A (CGA) antibodies. CGA-positive cells were found in 28 of 150 cases (18.7%) as an integral tumor component. In immunocytochemistry and electron microscopic examinations, we could classify these 28 cases into three groups according to the distribution patterns of CGA-positive cells. The first group consisted of 12 cases in which scattered CGA-positive cells were located in neoplastic glands. The second group consisted of six cases of scirrhous carcinoma in which CGA-positive cells were separated by fibrovascular tissue. The third group consisted of ten cases in which the positive cells were present in clusters. No definite correlation was recognized between the appearance of CGA cells and histologic types of predominance. In the analysis of the hormonal substances coexpressed by CGA-positive cells, immunoreactive serotonin (SER) was found most frequently, and somatostatin (SS), gastrin (GAS), glucagon/glicentin (GLU/GLI), and peptide-tyrosine-tyrosine (PYY) like immunoreactivities were found in a few tumor cells. CGA-positive cells occupied limited parts of the tumors in most cases, and they were noticeably more frequent in advanced stage cases. This might explain why endocrine differentiation reflects the dysexpression of the neoplastic stem cells. Furthermore, absence of mitotic figures in this type of cell and negativity of a single colony composed exclusively of CGA cells in metastatic foci suggested that these cells are in a dormant phase and are probably postmitotic.

Endocrine differentiation of gastric adenocarcinoma. The prevalence as evaluated by immunoreactive chromogranin A and its biologic significance

The prevalence of endocrine differentiation of conventional gastric adenocarcinoma was evaluated on the 212 cases (including 62 mucosal carcinomas) of consecutively resected stomach for adenocarcinoma in our hospital using anti-chromogranin A (CGA) antibodies. CGA-positive cells were found in 28 of 150 cases (18.7%) as an integral tumor component. In immunocytochemistry and electron microscopic examinations, we could classify these 28 cases into three groups according to the distribution patterns of CGA-positive cells. The first group consisted of 12 cases in which scattered CGA-positive cells were located in neoplastic glands. The second group consisted of six cases of scirrhous carcinoma in which CGA-positive cells were separated by fibrovascular tissue. The third group consisted of ten cases in which the positive cells were present in clusters. No definite correlation was recognized between the appearance of CGA cells and histologic types of predominance. In the analysis of the hormonal substances coexpressed by CGA-positive cells, immunoreactive serotonin (SER) was found most frequently, and somatostatin (SS), gastrin (GAS), glucagon/glicentin (GLU/GLI), and peptide-tyrosine-tyrosine (PYY) like immunoreactivities were found in a few tumor cells. CGA-positive cells occupied limited parts of the tumors in most cases, and they were noticeably more frequent in advanced stage cases. This might explain why endocrine differentiation reflects the dysexpression of the neoplastic stem cells. Furthermore, absence of mitotic figures in this type of cell and negativity of a single colony composed exclusively of CGA cells in metastatic foci suggested that these cells are in a dormant phase and are probably postmitotic.

Purification and characterization of salmolysin, an extracellular hemolytic toxin from Aeromonas salmonicida

An extracellular hemolytic toxin of Aeromonas salmonicida, termed salmolysin, was purified 945-fold by ammonium sulfate precipitation, anion-exchange chromatography on DEAE-cellulose, and gel filtration chromatography on Sephadex G-100 and Sepharose 2B. Salmolysin appeared homogeneous upon cellulose acetate membrane electrophoresis and immunodiffusion analysis. The molecular weight of the toxin was estimated to be approximately 200,000 by the sedimentation equilibrium method. The UV absorption spectrum showed a maximum at 275 nm and a minimum at 262 nm. The isoelectric point was found to be at pI 5.4. Carbohydrate and protein analyses and other biochemical data indicated that salmolysin is a glycoprotein, containing approximately 62% carbohydrates. The toxin is a heat-labile substance and is stable at a neutral pH value. Ferrous ion inhibited the activity, whereas metal-chelating agents did not affect the activity. Sulfhydryl reagents did not inhibit the toxin, whereas reducing agents, such as L-cysteine and reduced glutathione, inhibited the toxin to a certain extent. Salmolysin was inactivated by a nonionic detergent but was stimulated by an anionic detergent, sodium deoxycholate, at a low concentration. The toxin was also inactivated by subtilisin and trypsin but was not inhibited by papain and pepsin. Salmolysin, with a remarkable hemolytic activity against salmonid erythrocytes, was lethal to rainbow trout when it was injected intramuscularly.

Calcification in caval membrane causing primary Budd-Chiari syndrome: CT demonstration

We report two cases of membranous obstruction of the inferior vena cava (MOIVC) in which we observed patchy calcification in the membrane. The location of the calcification in the membrane was confirmed histologically. This finding was found histologically in four of eight cases of MOIVC, and it is a useful finding in the CT diagnosis of MOIVC.

Fine needle aspiration biopsy of primary malignant fibrous histiocytoma of the lung

Malignant cells were found on the fine needle aspiration (FNA) biopsy smears from a primary tumor of the lung. The cytologic specimen contained a mixture of fibroblastlike cells, histiocytelike cells, giant cells and undifferentiated cells; mitotic figures were also found. Histologic, histochemical and electron microscopic studies confirmed the FNA cytologic suggestion of a primary malignant fibrous histiocytoma of the lung.

Expression of glial fibrillary acidic protein (GFAP) in peripheral nerve sheath tumors. A comparative study of immunoreactivity of GFAP, vimentin, S-100 protein, and neurofilament in 38 schwannomas and 18 neurofibromas

Immunoreactivity of glial fibrillary acidic protein (GFAP) in 38 schwannomas and 18 neurofibromas was evaluated and compared with the reactivity of vimentin, S-100 protein, and neurofilament protein. All cases were positive for vimentin and S-100 protein. GFAP was positively stained in the neoplastic cells of 15 of 38 schwannomas (38%) and in two of 18 neurofibromas (11%). The extensively stained GFAP-positive tumors tended to be deeply situated in the body. The GFAP-positive cells were usually spindle-shaped and appeared preferentially in the perivascular region of hyalinized, thick blood vessels.

Specific deposition of serum amyloid A protein 2 in the mouse

The homogenates of amyloid-laden spleens prepared from CBA mice were analysed by SDS-PAGE and immunoblotting employing rat anti-murine monoclonal antibody, MSA 4-26. The results showed that the precursor of amyloid A protein (AA), serum amyloid A protein 2 (SAA2), and SAA intermediates with molecular weights of 10,000, 9000, and 8000 were contained in amyloid-laden tissues. The experiment using sonicated spleen cells and acute phase murine sera showed a delay in the degradation rate of SAA2 on cell fragments and the remains of SAA1 in supernatants. This result can explain disappearance of SAA2 from the murine serum during amyloidogenesis in vivo.

Papillary carcinoma of the thyroid gland with anaplastic transformation in the metastatic foci. An immunohistochemical study

An immunohistochemical study was made on an autopsy case of papillary carcinoma of the thyroid with anaplastic transformation in the metastatic foci occurring in a 72-year-old woman. The anaplastic carcinoma cells were sarcomatous in appearance, and they were vimentin-positive and cytokeratin-negative. Whereas, papillary tumor cells which were intermingled in the anaplastic carcinoma contained both cytokeratin and vimentin. The close correlation between tumor cell anaplasia and the expression of the different intermediate filament proteins in thyroid carcinoma was briefly discussed.

Carcinosarcoma of the esophagus. An immunohistochemical and electron microscopic study

Immunohistochemical and electron microscopic examinations were made of a carcinosarcoma of the esophagus in an 80-year-old man. An immunohistochemical examination showed that sarcomatous spindle cells were vimentin-positive, whereas squamous carcinoma cells were keratin-positive. No coexistence of vimentin and keratin in a single tumor cell was found. Electron microscopically, the sarcomatous spindle cells were characterized by well-developed rough endoplasmic reticulum, abundant intermediate filaments, and the occasional presence of peripheral aggregates of microfilaments. No definite desmosomes were identified among these cells. These results appear to indicate that most of the spindle-shaped tumor cells assume fibroblastic cellular features and synthesize the intermediate filament protein usually expressed in mesenchymal cells, even though such tumor cells could be epithelial in origin.

A case of malignant mesothelioma containing fibrous long-spacing fibers in the sarcomatous stroma

Fibrous long-spacing fibers (FLS) of a 90- to 120-nm period found in malignant mesothelioma of a 73-year-old woman were described. The FLS were observed in the reticular stroma with a fibroblastic variety of tumor cells, and they appeared to blend with bundles of thin collagen fibers and a moderate amount of ruthenium red (RR)-positive materials. No FLS were recognizable in the myxomatous stroma with abundant RR-positive materials or in the collagenous stroma packed with thick collagen fibers. Therefore, the presence of both thin collagen fibers and tumor cells of fibroblastic differentiation is presumed to be responsible for the formation of the FLS in the particular tumor.

Hyaline globules in yolk sac tumor. Histochemical, immunohistochemical and electron microscopic studies

Four cases of yolk sac tumor of the testis and ovary were examined by histochemistry, immunohistochemistry, and electron microscopy, and particular attention was directed toward the close relationship between hyaline globules and alpha fetoprotein (AFP). The hyaline globules were easily identified as eosinophilic globular structures located in the cytoplasm of the tumor cell as well as in the extracellular space. They were considered to be of glycoprotein in nature by their histochemical staining property. By an indirect immunoperoxidase method, the majority of intracytoplasmic hyaline globules were positive for AFP. Electronmicroscopically, the hyaline globules appeared as electron dense bodies with no limiting membranes. They were divided into two types by their electron density and inner structure: one is an electron high dense body consisting of homogeneous or fine granular materials and the other is a moderately electron dense body composed of fine filamentous structures similar to the basement membrane materials. It is suggested that the former corresponds with the AFP positive hyaline globules produces by the tumor cells of visceral type, while the latter represents the AFP negative globules formed by the cells of parietal type in non-neoplastic counterparts.