TEL-JAK2 transgenic mice develop T-cell leukemia

We previously reported a fusion between TEL and JAK2 in a t(9;12)(p24;p13) chromosomal translocation in childhood acute T-cell leukemia. This fusion gene encodes a TEL-JAK2 chimeric protein in which the 336 amino-terminal residues of TEL, including its specific self-association domain, are fused to the kinase domain of JAK2. TEL-JAK2 exhibits constitutive activation of its tyrosine kinase activity which, in turn, confers growth factor-independent proliferation to the interleukin-3-dependent Ba/F3 hematopoietic cell line. To elucidate the properties of TEL-JAK2 in primary cells and to create an animal model for TEL-JAK2-induced leukemia, we generated transgenic mice in which the TEL-JAK2 complementary DNA was placed under the transcriptional control of the EmuSRalpha enhancer/promoter. TEL-JAK2 founder mice and their transgenic progeny developed fatal leukemia at 4 to 22 weeks of age. Selective amplification of CD8-positive T cells was observed in blood, lymph nodes, thymus, spleen, and bone marrow. Expression of a tyrosine-phosphorylated TEL-JAK2 protein and activation of STAT1 and STAT5 (signal transducer and activator of transcription) were detected in leukemic tissues. TEL-JAK2 diseased mice also displayed invasion of nonhematopoietic organs, including liver, brain, lung, and kidney, by leukemic T cells. Leukemic organs of founder and transgenic progeny contained a monoclonal/oligoclonal T-cell population as analyzed by the rearrangement of the TCRbeta locus. Transplantation of TEL-JAK2 leukemic cells in nude mice confirmed their invasive nature. We conclude that the TEL-JAK2 fusion is an oncogene in vivo and that its expression in lymphoid cells results in the preferential expansion of CD8-positive T cells. (Blood. 2000;95:3891-3899)

Detection of the tax gene of HTLV-I in labial salivary glands from patients with Sjögren's syndrome and other diseases of the oral cavity

OBJECTIVE

To confirm a possible association between Sjögren's syndrome (SS) and the tax gene of human T lymphotropic virus type I (HTLV-I).

METHODS

We studied by PCR labial salivary glands (LSG) from 50 patients with definite SS and from 58 controls including 32 patients with LSG involved by other inflammatory processes and 26 normal LSG. Antibodies to HTLV-I and antibodies to the Tax protein were searched for in serum.

RESULTS

We detected the tax gene of HTLV-I in LSG from 15/50 (30%) of patients with SS but also in specimens from 9/32 (28%) patients with LSG involved by other inflammatory processes (3/9 graft-versus-host disease, 5/19 extra-vasated cysts, 1/4 sarcoidosis) and from only 1/26 (4%) normal LSG. A 652 bp region, sequenced in 2 SS patients, was 98-98.5% homologous to the canonic sequence of tax HTLV-I. The HTLV-I gag, pol and env genes were never detected. The serum of the SS patients did not contain antibodies to HTLV-I. However, anti-Tax antibodies were detected in the serum of 18/25 (72%) SS patients, 10/10 (100%) patients positive for tax DNA in their LSG and 8/15 (53%) patients negative for tax DNA in their LSG.

CONCLUSION

Our observations raise the possibility that a very low number of copies of the tax gene may be harbored innocuously in cells within the oral cavity in some healthy individuals, but that this gene may play a role as a co-factor in the development of SS or other diseases of oral cavity.

[Tissue hypereosinophilia]

Eosinophils are produced in the bone marrow and circulate in the peripheral blood in a quiescent state. After margination and emigration into tissues through postcapillary venules, eosinophils primarily reside in mucosal sites including the gastrointestinal and respiratory tracts. Eosinophilic gastroenteritis and the idiopathic chronic eosinophilic pneumonia, first described by Carrington, are the most characterized idiopathic diseases defined by an eosinophil infiltration restricted respectively to the gastrointestinal and the respiratory tracts. Differential diagnosis can be difficult since several disorders and particularly the idiopathic hypereosinophilic syndrome have many clinical, morphological and histological similarities.

[Carcinoma arising within mammary fibroadenomas. A study of six patients]

We report six cases of carcinomas arising within fibroadenomas. Fibroadenoma is a benign neoplasm occurring in young women. Its association with carcinomas is unfrequent and particularly reported in older women. Few data are available on the histologic features of fibroadenomas harboring malignant lesions. In this study, most cases of fibroadenomas showed cysts, sclerosing adenosis, epithelial calcifications or papillary apocrine changes. These fibroadenomas are classified as complex and are a long-term risk factor for breast cancer. The complex fibroadenoma may be specific of fibroadenoma associated with carcinoma.

[Hodgkin disease with nodular lymphocytic predominance or type I (paragranuloma of Poppema-Lennert): a clinico-pathological entity. Study of 21 cases and review of the literature]

We have studied clinical and pathological features of a series of 21 patients followed at the hospital Saint-Louis for a nodal nodular lymphocytic predominant Hodgkin's disease or paragranuloma of Poppema-Lennert. Histopathologically, all these lymph nodes were involved by a nodular proliferation of atypical cells, called pop corn cells with a B cell phenotype, admixed with small lymphocytes. Clinically, most patients were young males. The disease was localized except in one case and the prognosis good (only one death). However, one patient relapsed and another developped an aggressive lymphoma. These results were in keeping with different studies in the literature and confirmed that the paragranuloma is a clinicopathological entity, distinct from the classical Hodgkin's disease. Nowadays, it's strongly suggested that the pop corn cell is of centroblastic origin. Treatment remains controversial, however, according to most of the authors, patients with localized disease could be followed without treatment after surgical excision.

Stress-induced aberrant splicing of TSG101: association to high tumor grade and p53 status in breast cancers

The TSG101 gene, identified through insertional mutagenesis, is localized in a region that exhibits LOH in human cancers, suggesting that TSG101 might be a tumor suppressor gene. Numerous studies have then shown the presence of abnormal transcripts in various tumors which appear to result from aberrant splicing of the gene, rather than from intragenic deletions. Moreover, many studies demonstrated that these aberrantly spliced transcripts were not found in matched normal tissues. We have analysed TSG101 transcripts in 85 breast cancer samples and found that abnormal splicing of the gene is tightly correlated with tumor grade and p53 mutation. In addition, stress induced the appearance of these abnormal transcripts in primary lymphocytes. Hence, TSG101 splicing defects, while unrelated to the oncogenic process per se, could reflect the cellular environment of the tumor cells. The proposed role of stress and hypoxia to select p53 mutant cells could account for the tight association with p53 status.

Acute inflammatory intestinal vascular lesions and in situ abnormalities of the plasminogen activation system in Crohn's disease

OBJECTIVES

The distribution of the intestinal vascular lesions and their relation with the fibrinolysis process are poorly known in Crohn's disease (CD). The mediators of the plasminogen activator system, namely urokinase-type plasminogen activator (u-PA), tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor type-1 (PAI-1), are a key complex involved in fibrinolysis. The aims of this study were: (1) to further define vascular lesions and their distribution in the intestine; and (2) to study concomitantly the qualitative in situ expression and the levels of u-PA, t-PA and PAI-1 in the ileum of patients with CD.

PATIENTS AND METHODS

Histological, immunohistochemical and ultrastructural studies of vascular lesions in the resected ileum of 27 patients with CD were performed and compared with 36 control patients. Levels of u-PA, t-PA and PAI-1 measured by ELISA methods were compared in healthy and inflamed ileal tissues of 17 patients with CD.

RESULTS

Acute vascular lesions involving mainly serosal venules and capillaries were present in 63% of patients with CD vs 3/36 controls and were associated with PAI-1 expression. They were prominent on the mesenteric border beneath macroscopically normal mucosa. In contrast, chronic vascular lesions were present in all layers beneath mucosal ulcerations, where a significant increase of PAI-1 levels was found.

CONCLUSIONS

These results suggest that vascular involvement associated with abnormalities of PAI-1 expression is an early and widespread event in CD. Their prominence on the mesenteric border might explain the characteristic location of CD ulceration along the mesenteric margin.

[Eruptive epithelioid hemangioendothelioma with spindle cells. Nosological place in the spectrum of epithelioid vascular tumors]

The epithelioid vascular tumors include epithelioid hemangioma, epithelioid hemangioendothelioma and epithelioid angiosarcoma. We report the case of a difficult to define vascular epithelioid tumor. The tumor localized in the head developed in an eruptive way in multiple bone and skin locations in a 22-year-old man. The lesions had the same histological features as those of epithelioid hemangioma and epithelioid hemangioendothelioma with a spindle-cell component. This tumor was called eruptive epithelioid hemangioendothelioma with spindle cells. In our case, its development with recurrences and destructive features has some similarities to tumors of intermediate malignancy.

Eosinophilic airway inflammation in nasal polyposis

BACKGROUND

Asthma and asymptomatic bronchial hyperresponsiveness (BHR) are frequent findings in patients with nasal polyposis (NP).

OBJECTIVE

To elucidate mechanisms responsible for the development of BHR, we initiated a prospective study of bronchial inflammation as assessed by bronchial lavage (BL) and bronchial biopsy specimens in 35 patients with noninfectious NP.

METHODS

BHR was determined with methacholine provocation testing. Differential cell count, ECP, and histamine and tryptase levels were determined in BLs. Pathologic examination of bronchial biopsy specimens was performed with May-Grünwald-Giemsa stain to assess the number of lymphocytes. Indirect immunoenzymatic methods were used to identify eosinophils and mast cells.

RESULTS

Fourteen patients did not exhibit BHR (group A); 7 patients had asymptomatic BHR (group B); and 14 patients had BHR associated with asthma (group C). Patients of group C tended to have a longer duration of nasal symptoms than those of groups A and B. FEV1 (L) was significantly lower in group C than in groups A and B. The number and percentage of eosinophils were significantly higher in BLs in groups B and C than in group A (P <. 05). Patients of groups B and C had a significantly higher number of eosinophils in bronchial submucosa (14.0 +/- 1.5/mm2 and 19.0 +/- 1. 9/mm2, respectively) than patients of group A (0.1 +/- 0.1/mm2). The number of lymphocytes was also higher in groups B and C than in group A. FEV1 (percent of predicted value) and eosinophil number within bronchial mucosa correlated negatively.

CONCLUSION

Our results demonstrate that patients with NP and asymptomatic BHR had an eosinophilic bronchial inflammation similar to that observed in asthmatic patients with NP, whereas patients with NP without BHR do not feature eosinophilic lower airways inflammation. The clinical relevance of these results requires careful follow-up to determine whether eosinophilic inflammation in these patients precedes and is responsible for the development of obvious asthma.

Preoperative imaging of parathyroid glands with technetium-99m-labelled sestamibi and iodine-123 subtraction scanning in secondary hyperparathyroidism

BACKGROUND

Parathyroidectomy is unsuccessful in 10-30% of uraemic patients operated on for secondary hyperparathyroidism. We investigated the usefulness of preoperative radionuclide imaging, with simultaneous recording of the distribution images of iodine-123 and technetium-99m-labelled sestamibi.

METHODS

11 patients with secondary hyperparathyroidism underwent prospective imaging and parathyroidectomy. Plasma concentrations of intact parathyroid hormone (PTH) were measured in all patients before and 6 months after subtotal parathyroidectomy.

FINDINGS

Preoperative scanning showed 42 hot-spots suggesting enlarged parathyroid glands. 45 glands were discovered at surgery, and the parathyroidectomy was deemed successful in ten patients. Among the latter, one patient had a supernumerary parathyroid gland detected by scanning and resected from the left thymus. Another patient showed ectopic uptake corresponding to a large parathyroid gland in the upper mediastinum, and another had a parathyroid gland well above the thyroid. No false-positive scan findings were documented. In the patient for whom parathyroidectomy failed, preoperative scanning suggested five enlarged parathyroid glands, though the surgeon found only four glands, in their normal positions. Hyperparathyroidism persisted (intact PTH 527 ng/L, 6 months after surgery). A second scan confirmed the preoperative scan, showing a fifth parathyroid gland in the middle of the right thyroid lobe.

INTERPRETATION

Simultaneous recording of 99mTc-sestamibi and 123I improved the imaging of parathyroid glands in secondary hyperparathyroidism. The technique can identify ectopic and supernumerary parathyroid glands.

Interleukin-5 immunoreactivity and mRNA expression in gut mucosa from patients with food allergy

BACKGROUND AND AIMS

Eosinophils, mast cells and T lymphocytes are important cells in the allergic inflammatory process. These cells produce and are regulated by cytokines such as interleukin-3 (IL-3), interleukin-5 (IL-5) and granulocyte macrophage-colony stimulating factor (GM-CSF). We initiated this study to evaluate pathological abnormalities and to detect IL-5 in the duodenal mucosa from patients with food allergy.

METHODS

Endoscopy duodenal biopsy specimens were obtained from seven food-allergic patients, six atopic healthy controls and six nonatopic healthy controls. IL-5 protein was evaluated by immunohistochemistry. Electron microscopy as well as double immunofluorescent staining were used to identify the labelled cells and to localize IL-5. IL-5 mRNA expression was evaluated by qualitative polymerase chain reaction.

RESULTS

A significantly increased number of lymphocytes, mast cells and eosinophils was detected in the lamina propria in food-allergic patients and, in lower number, in atopic controls. Immunostaining for IL-5 was markedly positive in food-allergic patients, slightly increased in atopic controls and negative in nonatopic controls. Ultrastructurally, in food-allergic patients and in atopic controls, IL-5 was localized in eosinophil granules, in the matrix of intact granules and at the periphery of altered granules. Double immunofluorescent staining was performed in food-allergic patients and showed that 86.7% of IL-5+ cells were eosinophils, and that IL-5 was expressed by 24% of eosinophils. IL-5 mRNA was expressed in food-allergic patients but was not detected in atopic and nonatopic controls.

CONCLUSION

Activated eosinophils are involved in gut atopic reactions occurring in food allergy and are probably in part upregulated by their own local production of IL-5.

Retinoic acid and arsenic synergize to eradicate leukemic cells in a mouse model of acute promyelocytic leukemia

In acute promyelocytic leukemia (APL) patients, retinoic acid (RA) triggers differentiation while arsenic trioxide (arsenic) induces both a partial differentiation and apoptosis. Although their mechanisms of action are believed to be distinct, these two drugs both induce the catabolism of the oncogenic promyelocytic leukemia (PML)/RARalpha fusion protein. While APL cell lines resistant to one agent are sensitive to the other, the benefit of combining RA and arsenic in cell culture is controversial, and thus far, no data are available in patients. Using syngenic grafts of leukemic blasts from PML/RARalpha transgenic mice as a model for APL, we demonstrate that arsenic induces apoptosis and modest differentiation, and prolongs mouse survival. Furthermore, combining arsenic with RA accelerates tumor regression through enhanced differentiation and apoptosis. Although RA or arsenic alone only prolongs survival two- to threefold, associating the two drugs leads to tumor clearance after a 9-mo relapse-free period. These studies establishing RA/arsenic synergy in vivo prompt the use of combined arsenic/RA treatments in APL patients and exemplify how mouse models of human leukemia can be used to design or optimize therapies.

Meningioma in long-term survivors after allogeneic bone marrow transplantation

Late complications occurring after allogeneic bone marrow transplant (BMT) are increasingly reported, since more patients survive. Among these late complications, solid tumors are of particular clinical concern. Only malignant brain tumors have been reported (astrocytoma, glioblastoma). We describe two cases of meningiomas developing 13 and 15 years after the graft. Occurrence of such benign tumors has been described after treatment of ALL, but not following allogeneic BMT. It is important to consider the diagnosis of meningioma in long-term survivors presenting with neurological symptoms.

[Paraneoplastic pemphigus with tracheobronchial involvement]

BACKGROUND

Paraneoplastic pemphigus is a bullous skin disease with characteristic polymorphous clinical presentation and precise histological and immunological features. We report a case of paraneoplastic pemphigus associated with chronic lymphoid leukemia involving the tracheobronchial epithelium.

CASE REPORT

A patient with chronic lymphoid leukemia developed pluriorificial lesions. There were several conjunctival, buccal and genital erosions associated with erosive plaques on the trunk, Nikolski's sign and bullous lesions suggestive of paraneoplastic pemphigus. Histology examination of a bulla showed intraepidermal blistering and suprabasal acantholysis. Direct immunofluorescence evidenced intercellular IgG and C3 deposits. Search for anti-intercellular substance antibodies was positive with fluorescence on specific paraneoplastic pemphigus substrates. At immunotransfer, the serum recognized several bands corresponding to 250, 230, 210 and 190 kD antigens, confirming the diagnosis of paraneoplastic pemphigus. Several days later, the patient's general condition deteriorated with bronchorrhea. Bronchial endoscopy visualized ulceronecrotic plaques. Tracheal biopsy evidenced acantholytic cells and intraepithelial cleavage. General corticosteroid therapy was initiated and led to improvement of the skin lesions but the patient died rapidly from pneumonia. Autopsy confirmed the presence of epithelial cleavage and acantholysis involving the trachea and bronchi.

DISCUSSION

This case illustrates the difficulty of diagnosing paraneoplastic pemphigus in the early stages. The pluriorificial lesions were suggestive of a Stevens-Johnson syndrome. Besides the genital, conjunctival and buccal mucosa, other mucosa can be involved. In our case, despite the absence of an immunological element, histology was highly suggestive of specific tracheobronchial localizations. The presence of such lesions, which should be searched for in all cases with bronchopulmonary manifestations, worsens the prognosis.

Squamous cell carcinomas after allogeneic bone marrow transplantation for aplastic anemia: further evidence of a multistep process

BACKGROUND

Secondary solid tumors are rare events occurring in patients who underwent allogeneic marrow transplantation for aplastic anemia and Fanconi's anemia. Human herpes virus 8 (HHV8), Epstein-Barr virus (EBV), and human papillomaviruses (HPV) sequences have been found in squamous cell carcinoma (SCC) occurring in organ transplant recipients. The tumor suppressor gene p53 has been strongly linked to the occurrence of SCC in the nonimmunocompromised population.

PATIENTS AND METHODS

In eight patients with SCC, we searched for HHV8, EBV, varicella zoster virus, adenovirus, and HPV sequences from DNA extracted from selected areas of SCC. We also looked for p53 expression in those specimens as well as the presence of anti-p53 antibodies in the serum of these patients at the onset of SCC.

RESULTS

In one patient, we found the presence of both HHV8 and EBV sequences, and in another patient we found HPV16 sequences. All five tumors that could be studied disclosed evidence of p53 accumulation, but none of the eight patients had anti-p53 antibodies in the sera.

CONCLUSION

SCC developing in marrow transplant recipients seems to occur via a multistep process. Genetic predisposition may be present, as in patients with Fanconi's anemia. Transplantation-related factors, such as irradiation and chronic graft-versus-host disease, also have a role. In this article, we add two more potent risk factors: p53 alteration(s) and in some cases the presence of oncogenic viruses.

[The correlation between salivary endothelial expression of E-selectin and clinical and biological parameters in systemic scleroderma]

OBJECTIVES

A body of evidence suggests the pivotal role of endothelial cells in the pathophysiology of systemic sclerosis. E-selectin is an adhesion molecule specifically expressed by activated endothelial cells. In previous studies we noticed that E-selectin was frequently expressed in the salivary gland tissue of patients with systemic sclerosis. Moreover, E-selectin expression was detectable very early in the course of the disease. To better define the role of E-selectin in the pathogenesis of systemic sclerosis, we conducted a study aimed at determining whether E-selectin expression was correlated to clinical and biological features in patients with systemic sclerosis.

METHODS

Thirty-one patients presenting with systemic sclerosis were included in the study. The following parameters were systematically assessed: duration and cutaneous extent of the disease, presence of secondary Sjögren's syndrome, antinuclear antibodies, and pulmonary and esophagus involvement. E-selectin expression was assessed by immunocytochemistry on minor labial salivary glands.

RESULTS

E-selectin expression was detected in 21 out of 31 patients (67%). The disease duration was significantly shorter in patients with E-selectin expression (mean 9.1 +/- 8.5 years versus 4.2 +/- 3.3 years, P < 0.05). No significant difference was found for other features.

CONCLUSIONS

This study shows that endothelial E-selectin expression is mainly detectable early in the course of systemic sclerosis, when active and non-cicatrical sclerosis may be evidenced. No correlation was found between E-selectin expression and immunological disorders (antinuclear antibodies, secondary Sjögren's syndrome).