Merkel cell carcinoma with partial spontaneous regression: an immunohistochemical, ultrastructural, and TUNEL labeling study

We report a case of Merkel cell carcinoma that partially regressed after biopsy. A 76-year-old woman presented with an 1 month history of a rapidly enlarging nodule on her left cheek. After biopsy, the nodule reduced to almost half the size and was excised 1 month later. The excised specimen showed a dense cluster of lymphocytes and fibrosis around the tumor nests. In addition, lymphocytes showed apposition with tumor cells. An immunohistologically dense, even infiltration of CD4+ and CD8+ cells was found around the tumor nests, and more CD8+ cells than CD4+ cells were seen in the tumor nests. By electron microscopy (EM), apoptosis of tumor cells and lymphocytes was observed. Many apoptotic cells were also detected by in situ nick end-labeling (TUNEL) of DNA-breaks, especially in the marginal area of tumor nests surrounded by dense lymphocytic infiltrates. It seems likely that T-cell immunity, which induces apoptosis of tumor cells, may have been involved in tumor regression.

Intraosseous hemangioma of the vomer: a case report

We describe an unusual case of intraosseous hemangioma of the vomer. The lesion had a characteristic radiographic appearance, especially on the computed tomographic scan. The two most interesting points in this case were the rarity as a site for the occurrence of hemangioma and the successful extirpation of the tumor via the Le Fort 1 osteotomy approach without embolization of the feeding vessels. The benefits of this approach included the wide surgical field afforded deep in the midface region, which was important for controlling bleeding, as well as the complete extirpation of the tumor.

Verruciform xanthoma in association with a vulval fibroepithelial polyp

We report the clinical, light microscopic, immunohistochemical and ultrastructural features of a verruciform xanthoma that developed in association with a vulval fibroepithelial polyp. To our knowledge, this is the first time that this association has been reported. Immunohistochemical findings confirmed that the xanthoma cells were of a monocyte/macrophage lineage. In addition to typical histological characteristics, prominent vascular ectasias were detected in the deep dermis at the periphery of this lesion. The ectasias may play a part in pathogenesis.

Endogenous CCK inhibits colonic contractions in unrestrained conscious rats

As cholecystokinin octapeptide (CCK-OP) and feeding have been reported to relax the circular muscle contractions of the proximal colon in unrestrained conscious rats under fasting conditions, the, action of cholecystokinin, released after duodenal infusion of a low residual diet of clinimeal, was studied on the motor activity of the proximal colon in unrestrained conscious rats. We used an implantable telemetry system with a miniature strain gauge force transducer introduced into the rat proximal colon. By using a specific radioimmunoassay system for CCK, plasma levels of CCK before and after duodenal infusion of clinimeal (0.5, 1.0, 2.0 ml) were determined at 0, 5, 10, 20, 30, 60 min in the portal blood. The clinimeal infusion caused a significant increase in CCK levels of the portal plasma during 5 and 30 min. This increase was in a dose-dependent manner. In accordance with this increase in plasma CCK, the motor activity of the proximal circular muscle was suppressed significantly. A bolus injection of the CCK A receptor antagonist, loxiglumide, CR 1505 (0.1, 0.5 and 1.0 mg/kg ip), prior to clinimeal blocked the inhibitory action of CCK on the motor activity in a concentration-dependent manner. These data suggest that endogenous CCK released by a residual diet is involved in the mechanism of inhibition of motor activity in the proximal colon.

Comparison of platelet-activating factor receptor mRNA levels in peripheral blood eosinophils from normal subjects and atopic asthmatic patients

Platelet-activating factor (PAF) modulates the functions of eosinophils, which play an important role in allergic inflammation, through a specific receptor(s) expressed on the cell surface. We compared expression levels of mRNA for the PAF receptor (PAF-R) in peripheral blood eosinophils from atopic asthmatic patients with those from normal healthy subjects using a relative quantification method based on the reverse transcription-polymerase chain reaction (RT-PCR). We found that the levels of PAF-R mRNA in eosinophils from the patients were significantly higher than those in normal subjects. These results suggest that the increased expression of PAF-R in eosinophils may be relevant to the pathogenesis of atopic asthma.

Acute cutaneous barrier perturbation induces maturation of Langerhans' cells in hairless mice

Perturbation of the cutaneous water permeability barrier has been shown to result in many physiological events in keratinocytes, including upregulation of proinflammatory cytokine production. However, little is known about the effect of barrier disruption on Langerhans' cells (LC). In the present study, we examined whether acute barrier perturbation by acetone treatment or tape stripping affects the phenotypes and functions of LC in male hairless mice. Both procedures resulted in a two- to five-fold increase in the expression of MHC class II antigens, B7-2 and intercellular adhesion molecule-1 on LC, whereas no significant changes were detected in levels of B7-1. Levels of intracellular interleukin-1 beta, as determined by flowcytometry, were also increased 1 h after acetone treatment or tape stripping. LC obtained from barrier-disrupted mice induced a significant increase in syngeneic and allogeneic T-cell proliferation, compared to those from saline-treated mice. These results indicate that LC play a crucial role in maintaining cutaneous homeostasis against increasing exposure to external substances resulting from barrier disruption.

Effect of enprostil on omeprazole-induced hypergastrinemia and inhibition of gastric acid secretion in peptic ulcer patients

This study was performed to examine the effects of additional enprostil administration on hypergastrinemia and gastric acid suppression induced by omeprazole. Serum gastrin concentrations were measured in 10 peptic ulcer patients (six Helicobacter pylori-positive and four Helicobacter pylori-negative patients) before treatment, after two weeks of omeprazole (20 mg/day), and after two weeks of omeprazole and enprostil (50 micrograms/day). The additional acid inhibitory effect of enprostil was evaluated by 24-hr intragastric pH measurements in five healthy Helicobacter pylori-negative volunteers. After omeprazole treatment, the serum gastrin level of Helicobacter pylori-positive patients (3.5-fold of control) was markedly higher than that of Helicobacter pylori-negative patients (1.7-fold of control). Additional treatment with enprostil suppressed serum gastrin levels to 0.4-fold and 0.7-fold of omeprazole treatment levels in Helicobacter pylori-positive and Helicobacter pylori-negative patients, respectively. In healthy volunteers, median pH recorded during the nonmeal daytime interval increased significantly with additional enprostil. Thus, enprostil reduces undesirable omeprazole-induced hypergastrinemia, especially in Helicobacter pylori-positive patients, and effectively suppresses acid secretion.

Protein expression of fibroblast growth factor receptor-1 in keratinocytes during wound healing in rat skin

Fibroblast growth factors have been shown to play important roles in wound healing. To define their sites of action, we examined the expression of fibroblast growth factor receptor-1 (FGFR-1) during burn wound healing in rat skin by immunohistochemistry and western blot analysis. In cryostat sections of intact skin, little or no staining was observed. After a burn, however, staining for FGFR-1 was found in newly forming epidermis. The suprabasal layer of such epidermis, composed mostly of regenerating keratinocytes, was stained intensely, whereas keratinocytes in newly forming hair follicles were devoid of staining. Staining gradually decreased week by week after wound closure and was hardly visible 10 weeks after the burn, when the thickness of the epidermis had returned to the normal level. Staining was also found in small blood vessels and capillaries of granulation tissues of the dermis. Western blot analysis using the same antiserum was performed in the newly forming epidermis 10 d after the burn. A single band was detected with an apparent molecular weight of 120 kDa, corresponding to the short membrane-bound form of rat FGFR-1. Our study indicates that FGFR-1 is expressed during wound healing, mainly in regenerating epidermis and to some extent in blood vessels of the dermis. Fibroblast growth factors may affect the proliferation and differentiation of epidermal keratinocytes as well as angiogenesis in the dermis via the FGFR-1 expressed during wound healing.

Calcium channel blockers suppress the contact hypersensitivity reaction (CHR) by inhibiting antigen transport and presentation by epidermal Langerhans cells in mice

Since Langerhans cells (LC) are the principal antigen-presenting cells among epidermal cells, treatments suppressing LC function may inhibit CHR. Although calcium channel blockers (CCB) have been shown to suppress the functions of several immunologically active cells, little is known about their effect on LC. In this study we show that pretreatment with topical 1% nifedipine or verapamil HCl significantly suppressed both the sensitization and elicitation phases of a CHR in mice. We then investigated whether CCB affected LC. Flow cytometric analysis of regional lymph node cells obtained 24 h after applying FITC demonstrated that topical CCB treatment significantly reduced the percentage of FITC+ NLDC-145+ cells, suggesting that CCB had suppressed antigen transport by LC. In vitro treatment with nifedipine or verapamil significantly suppressed the antigen-presenting capacity of LC in a dose-dependent manner. In addition, in vitro CCB treatment reduced the percentage of class II MHC antigen-positive epidermal cells and significantly suppressed class II MHC and B7-1 levels in LC, as determined by flow cytometry and reverse transcriptase-polymerase chain reaction, whereas surface expression of B7-2 and mRNA was only weakly reduced. Neither expression of CD45 nor the percentage of CD45+ cells were affected, suggesting that the effects of CCB on LC were not due to cytotoxicity. Our results suggest that CCB inhibit CHR, at least in part, by suppressing the functions of LC.

Angiosarcoma of the scalp associated with renal transplantation

A case of cutaneous angiosarcoma occurring in a 51-year-old male renal transplant patient is reported. Multiple violaceous nodules surrounded by poorly demarcated red to purple discoloration were found on his scalp. Immunosuppressants consisting of azathioprine and prednisolone had been administered during the 12-year period since the renal transplantation. We diagnosed the lesion clinically as a cutaneous angiosarcoma and performed a wide surgical excision. The histopathological findings confirmed the diagnosis and showed tumour cells in the peripheral margin. Postoperatively, the patient started immunotherapy with systemic administration of recombinant interleukin-2 (rIL-2), but he refused to continue it because of the acute rejection of the transplanted kidney induced by the rIL-2. Instead he received radiation therapy (total 7000 rad) of the scalp. Although no recurrence was noticed for 15 months after the completion of radiation, he died due to lung metastasis from angiosarcoma. We review the seven cases, including ours, of angiosarcoma after renal transplantation that are reported in detail in the literature.

Inhibition by 2-arachidonoylglycerol, a novel type of possible neuromodulator, of the depolarization-induced increase in intracellular free calcium in neuroblastoma x glioma hybrid NG108-15 cells

2-Arachidonoylglycerol was found to inhibit the depolarization-induced increase in [Ca2+]i in NG108-15 cells differentiated with prostaglandin E1 and theophylline in a dose-dependent manner. Such an effect appears to be rather specific to polyunsaturated fatty acid-containing monoacylglycerols such as 2-arachidonoylglycerol. Neither 2-palmitoylglycerol nor free arachidonic acid exhibited appreciable inhibitory activity. These observations raise the possibility that 2-arachidonoylglycerol attenuates the increase in [Ca2+]i, thereby modulating several neural functions in this type of cell.

Nitric oxide is involved in the inhibitory action of cholecystokinin octapeptide (CCK-OP) on proximal colonic motility

To determine whether nitric oxide (NO) is a possible mediator in the inhibitory action of CCK-octapeptide (CCK-OP) on circular muscle contractions of the rat proximal colon, contractile activities of the circular muscle were recorded in the proximal colon of unrestrained conscious rats in the fasting state using a miniature strain gauge force transducer and an implantable telemetry system. Regular and rhythmic phasic contractions were observed during the fasted condition, similar to the myoelectric migrating complex seen in intestinal contractions of the fasting dog. These phasic contractions were almost completely inhibited after intraperitoneal (i.p.) administration of CCK-OP at a dose of 15 microg/kg body weight. N(omega)-nitro-arginine, methyl ester (L-NAME), at doses of 20 and 200 mg/kg i.p. administered prior to i.p. injection of CCK-OP, prevented the inhibitory action on the fasting phasic contractions. The degree of prevention was dose-dependent. 100 mg/kg body weight i.p. injection of L-arginine inhibited the circular muscle contractions. The same dose of D-arginine had no action on contractions of the circular muscle of the proximal colon in the fasted rat. From these data, we conclude that NO is one possible mediator in the inhibitory mechanism of CCK-OP on smooth muscle motor activity of the rat proximal colon in vivo.

Cutaneous infiltration by leukemic cells in acute promyelocytic leukemia of a child after treatment with all-trans retinoic acid

We describe here the first case of childhood acute promyelocytic leukemia (APL) with cutaneous infiltration of leukemic cells following treatment with all-trans retinoic acid (ATRA) confirmed by immunostaining and polymerase chain reaction for PML/RAR alpha. An 11-year-old girl was diagnosed as having APL. Chromosomal analysis demonstrated the characteristic karyotype of t(15;17). ATRA therapy was begun at a dose of 45 mg/m2 daily. During ATRA therapy, leukocytosis and retinoic acid syndrome were observed but were resolved by dexamethasone. Two months after commencement of ATRA therapy, complete remission was achieved. During the course of consolidation chemotherapy, however, multiple cutaneous nodules developed in her trunk, the size and number of which increased despite intensive chemotherapy. Histological and immunological studies of the cutaneous nodules showed infiltration of leukemic cells. PML/RAR alpha mRNA was detected in both the cutaneous nodules and bone marrow by means of polymerase chain reaction. ATRA treatment for APL may be associated with an increased incidence of extramedullary disease such as cutaneous lesions. The best available therapy for APL may be a combination of ATRA and chemotherapy, especially when a marked leukocytosis occurs during ATRA therapy.

2-Arachidonoylglycerol, a putative endogenous cannabinoid receptor ligand, induces rapid, transient elevation of intracellular free Ca2+ in neuroblastoma x glioma hybrid NG108-15 cells

Low concentrations of 2-arachidonoylglycerol were found to induce rapid, transient elevation of intracellular free Ca2+ in NG108-15 cells (EC50 was 150 nM). Free arachidonic acid, 2-palmitoylglycerol, 2-oleoylglycerol, 2-linoleoylglycerol and 2-docosahexaenoylglycerol were inactive. Anandamide acted as a partial agonist. Importantly, desensitization was observed upon sequential challenge with 2-arachidonoylglycerol. Furthermore, cross-desensitization was observed between 2-arachidonoylglycerol and WIN 55212-2, a cannabinoid receptor agonist. Pretreatment of the cells with SR141716A, a cannabinoid receptor antagonist, abolished the activities of both 2-arachidonoylglycerol and WIN 55212-2. These results strongly suggest that 2-arachidonoylglycerol and WIN 55212-2 bind to a common cannabinoid receptor to elicit cellular responses and that 2-arachidonoylglycerol has some physiological role in nervous tissues.

Therapeutic effect of egualen sodium (KT1-32), a new antiulcer agent, on chronic gastritis induced by sodium taurocholate in rats

We investigated the therapeutic effects of egualen sodium (KT1-32), a new antiulcer agent, on chronic erosive and atrophic gastritis induced by 5 months' administration of sodium taurocholate (TCA; 5 mM) in rats. The chronic gastritis was manifested by mucosal surface injuries (erosions), reduced mucosal thickness, reduction of the number of parietal cells, infiltration of inflammatory cells, and proliferation of collagenous fiber. Egualen sodium, (10-100 mg/kg, t.i.d.) administered orally to the rats for 2 weeks after the withdrawal of TCA, dose-dependently and significantly decreased the total length of erosions. The indicators of atrophic gastritis, i.e., reduced mucosal thickness and reduction in the number of parietal cells, were improved dose-dependently by the administration of this agent. Egualen sodium also reduced the inflammatory cell infiltration and the proliferation of collagenous fiber in the gastric mucosa in a dose-dependent manner. The reduced staining of neutral gastric mucus was improved by a high dose (100 mg/kg) of egualen sodium. The therapeutic effects of egualen sodium on experimental gastritis were superior to those of sofalcone and sodium guaiazulene 3-sulfonate. These results suggest that egualen sodium may be a promising agent for the treatment of erosive and atrophic gastritis.

Interleukin-12 activates human gamma delta T cells: synergistic effect of tumor necrosis factor-alpha

gammadelta T cell populations are known to expand in response to intracellular bacterial infectious agents regardless of previous priming. We have shown previously that soluble factor(s) produced by Mycobacterium-stimulated monocytes activate cord blood gammadelta T cells to proliferate. In this study, we investigated whether cytokines produced by monocytes are responsible for gammadelta T cell activation in vitro: interleukin (IL)-1beta, IL-6, IL-8, IL-12, tumor necrosis factor (TNF)-alpha and granulocyte/macrophage colony-stimulating factor were examined. Recombinant human IL-12 stimulated gammadelta T cells, but not alphabeta T cells in peripheral blood mononuclear cells, to express CD25 on their surfaces, and to expand in number in vitro. IL-12-primed gammadelta T cell numbers increased to a greater extent in the culture to which exogenous IL-2 (5 U/ml) was added. Anti-TNF-alpha monoclonal antibody inhibited IL-12-induced up-regulation of CD25 on gammadelta T cells, suggesting that endogenous TNF-alpha may play a role in IL-12-induced activation of gammadelta T cells. Recombinant TNF-alpha synergistically augmented IL-12-induced activation of gammadelta T cells. Furthermore, IL-12 up-regulated TNF receptors on gammadelta T cells in vitro: TNF-alpha binding to its receptor induced CD25 expression on the gammadelta T cells in an autocrine or paracrine fashion, or perhaps both. It also became evident that both IL-12 and TNF-alpha were produced by mycobacterial lysate-stimulated monocytes. Taken together, these results suggest that upon confrontation with mycobacterial organisms, gammadelta T cells can be quickly and antigen-nonspecifically activated by soluble factors including IL-12 and TNF-alpha, both of which are produced by mononuclear phagocytes in response to mycobacterial organisms.

Regulation by IL-5 of expression of functional platelet-activating factor receptors on human eosinophils

Platelet-activating factor (PAF) and IL-5 are both important mediators of various allergic reactions, although the relationship between these mediators in allergic responses has not yet been fully elucidated. In this study, we investigated the effects of human rIL-5 on the expression of the PAF receptor (PAF-R) on eosinophils from healthy human volunteers. The specific binding of [3H]WEB 2086, a specific ligand for PAF-R, to eosinophils treated with 5 ng/ml of IL-5 for 12 h was significantly higher than that to untreated cells. The Bmax value for IL-5-treated eosinophils was 1.8-fold higher than that for untreated cells, while the Kd values remained unchanged. This clearly indicates that surface expression of PAF-R on eosinophils is enhanced by IL-5. The enhancement was first observed at 6 h and reached a plateau at 12 to 18 h. The effect of IL-5 was abolished in the presence of cycloheximide or actinomycin D. When the relative amount of PAF-R mRNA was determined by reverse transcription PCR, the message was found to be increased through activation of transcription of transcript 1 on exposure to IL-5. Furthermore, we found that the PAF-induced increase in intracellular calcium ion concentration in eosinophils was markedly augmented by exposure to IL-5 for 12 h. Several lines of data suggest that the enhanced expression of PAF-R on eosinophils due to IL-5 is the cause of the augmented response to PAF. These findings will be of value for understanding the mechanisms of selective infiltration and activation of eosinophils in allergic diseases in which PAF and IL-5 are crucially involved.

Regulation by IL-5 of expression of functional platelet-activating factor receptors on human eosinophils

Platelet-activating factor (PAF) and IL-5 are both important mediators of various allergic reactions, although the relationship between these mediators in allergic responses has not yet been fully elucidated. In this study, we investigated the effects of human rIL-5 on the expression of the PAF receptor (PAF-R) on eosinophils from healthy human volunteers. The specific binding of [3H]WEB 2086, a specific ligand for PAF-R, to eosinophils treated with 5 ng/ml of IL-5 for 12 h was significantly higher than that to untreated cells. The Bmax value for IL-5-treated eosinophils was 1.8-fold higher than that for untreated cells, while the Kd values remained unchanged. This clearly indicates that surface expression of PAF-R on eosinophils is enhanced by IL-5. The enhancement was first observed at 6 h and reached a plateau at 12 to 18 h. The effect of IL-5 was abolished in the presence of cycloheximide or actinomycin D. When the relative amount of PAF-R mRNA was determined by reverse transcription PCR, the message was found to be increased through activation of transcription of transcript 1 on exposure to IL-5. Furthermore, we found that the PAF-induced increase in intracellular calcium ion concentration in eosinophils was markedly augmented by exposure to IL-5 for 12 h. Several lines of data suggest that the enhanced expression of PAF-R on eosinophils due to IL-5 is the cause of the augmented response to PAF. These findings will be of value for understanding the mechanisms of selective infiltration and activation of eosinophils in allergic diseases in which PAF and IL-5 are crucially involved.

[A patient with HCC successfully treated by ethanol injection therapy with etoposide]

A patient with hepatocellular carcinoma (HCC) who underwent successfully percutaneous ethanol injection therapy (PEIT) with etoposide was reported. A 72-year-old Japanese man with positive HCV-Ab developed multiple tumors of HCC. He underwent transcatheter arterial embolization (TAE) four times and PEIT three times, but the growth of tumors (particularly, S8) could not be controlled by these modalities. Then, the mixture of etoposide (20 mg), ethanol (8.5 ml) and lipiodol (1.5 ml) was injected into S6 tumors. Consistent with the normalization of serum AFP level, CT scan revealed the marked remaining lipiodol in these tumors. PEIT with etoposide is the treatment of choice in patients with HCC refractory to treatment by conventional TAE or PEIT.

[Locoregional injection of OK-432/fibrinogen/thrombin for unresectable metastatic liver tumors]

We performed the locoregional injection of OK-432/fibrinogen/thrombin to unresectable hepatic tumors metastasized from colorectal cancers, which were hardly controlled by arterial infusion chemotherapy. CEA was markedly decreased following this treatment, although abdominal CT did not show a significant reduction of tumor mass. This immuno-injection therapy may be a choice of treatment for metastatic liver tumors, refractory to treatment by conventional chemotherapy.

[A patient with hepatocellular carcinoma originating from the caudate lobe, who underwent hepatectomy following microwave coagulation therapy]

Hepatocellular carcinoma (HCC) originating from the caudate lobe is rare (about 2%), and prognosis is poor due to difficulties in early diagnosis, transarterial chemoembolization (TAE), and surgical resection. Distant metastasis is also likely to develop. To prevent metastasis during surgical manipulations, we performed microwave coagulation therapy before caudate lobectomy in one patient. Although the efficacy of this procedure remains to be elucidated, the multidisciplinary treatment described in this study is essential for the improvement of prognosis in patients with HCC developing from caudate lobe.

[A patient with unresectable cancer of pancreas head, effectively treated by a local injection of the mixture of OK-432, fibrinogen and thrombin]

The effective treatment of unresectable pancreatic cancer remains to be elucidated. We report herein a patient who underwent a local injection of a mixture of OK-432, fibrinogen and thrombin. Tumor size and tumor markers significantly decreased following this procedure. Local injection therapy with OK-432, fibrinogen and thrombin may be a promising treatment for unresectable pancreatic cancer.