Immunological changes in the ascites of cancer patients after intraperitoneal administration of the bispecific antibody catumaxomab (anti-EpCAM×anti-CD3).

OBJECTIVE: To explore the effects of intraperitoneal (i.p.) infusion of catumaxomab, a bispecific monoclonal antibody (anti-EpCAM×anti-CD3), on T cells, NK cells and macrophages in ascites of cancer patients and to understand how ascitic immune cells can be activated despite the pervasive immunosuppressive ability of ascites microenvironment. METHODS: Six patients with malignant ascites received i.p. catumaxomab infusion. Ascitic immune cells were profiled by flow cytometry and gene expression at baseline and after i.p. catumaxomab infusion. In vitro experiments enabled investigations on the adverse effect of ascites microenvironment on catumaxomab-stimulated immune cells. RESULTS: I.p. catumaxomab infusion enhanced the expression of the CD69 and CD38 activation molecules in CD4(+) and CD8(+) T cells, NK cells and macrophages, and favoured CD8(+) T cell accumulation into the peritoneal cavity. An analogous immune cell activation as well as IFN-γ and IL-2 production were induced by catumaxomab in vitro. In vitro experiments showed that the immunosuppressive milieu of ascites abrogated all the immunostimulatory activities of catumaxomab. Adding EpCAM(+) tumour cells to the culture permitted both catumaxomab Fab regions to engage cognate antigens and restored immunostimulatory catumaxomab activity. CONCLUSIONS: This is the first demonstration in a clinical setting that i.p. catumaxomab infusion activates NK cells and macrophages in addition to T cells in ascites and favours CD8(+) T cell accumulation into the peritoneal cavity. Moreover, our findings indicate that the concomitant binding of both catumaxomab Fab regions delivers an activation signal that is strong enough to activate immune cells despite the prevailing immunosuppressive environment of malignant ascites.

[Type II enteropathy-associated T-cell lymphoma: a clinicopathologic study].

OBJECTIVE: To study the clinicopathologic features, immunohistochemical findings, differential diagnosis and prognosis of type II enteropathy-associated T-cell lymphoma (EATL). METHODS: Fourteen cases of type II EATL encountered in Department of Pathology, Nanjing General Hospital were retrospectively reviewed. The clinical data, histologic features, immunohistochemical findings and follow-up information were analyzed, with literature review. RESULTS: There were altogether 12 males and 2 females. The median age of patient was 49 years. The sites of involvement included jejunum (10 cases) and ileum/colon (4 cases). The patients often presented with an abdominal mass, abdominal pain, diarrhea and constitutional symptoms such as fever, night sweating and cachexia. There was no clinical evidence of gluten-sensitive enteropathy. Histologically, the lymphoma cells showed full-thickness infiltration of the intestinal wall. They contained round hyperchromatic nuclei and pale cytoplasm. The stroma was minimally inflamed, with or without associated coagulative necrosis. A remarkable finding was the presence of villous atrophy, cryptal hyperplasia and intraepithelial lymphocytosis. Immunohistochemical study showed that the tumor cells expressed CD3, CD43 and CD8 (14/14). Some of them were also positive for CD56 (11/14) and CD30 (2/14). The staining for CD4, CD20, CD79a and myeloperoxidase was negative. A high proliferation index was demonstrated by Ki-67 immunostain. In-situ hybridization for EBER was negative. Follow-up data were available in 9 cases. The duration of follow-up ranged from 6 months to 36 months. Seven patients died within 14 months. CONCLUSIONS: EATL is a rare type of lymphoma with intestinal involvement. Associated enteropathy is not demonstrated, in contrast to cases encountered in Nordic countries. A correct diagnosis requires evaluation of clinical manifestations, pathologic features and ancillary study results.

Immunophenotype and molecular characterisation of adenocarcinoma of the small intestine.

BACKGROUND: Despite having a dramatically larger surface area than the large intestine, the small intestine is an infrequent site for the development of adenocarcinoma. To better understand the molecular abnormalities in small bowel adenocarcinoma (SBA), we characterised a number of candidate oncogenic pathways and the immunophenotype of this rare cancer. METHODS: Tissue microarrays were constructed from tumour samples from 54 patients with all stages of the disease. Immunohistochemistry and microsatellite instability (MSI) testing were conducted. RESULTS: The profile of cytokeratin 20 and 7 coexpression was variable, but expression of caudal type homeobox transcription factor 2 (CDX2) was present in 70% of cases. In this young population (median age 54 years), loss of mismatch repair (MMR) proteins occurred in 35% of patients, with confirmed MSI in 100% of tested cases. Expression of vascular endothelial growth factor-A (VEGF-A) and epidermal growth factor receptor (EGFR) was common, occurring in 96 and 71% of patients, respectively. Only one case showed HER2 expression and none showed loss of phosphatase and tensin homologue mutated on chromosome 10 (PTEN). CONCLUSIONS: These results suggest that alterations in DNA MMR pathways are common in SBAs, similar to what is observed in large bowel adenocarcinomas. Furthermore, the high percentage of tumours expressing both EGFR and VEGF suggests that patients with this rare cancer may benefit from therapeutic strategies targeting EGFR and VEGF receptor (VEGFR).

Immune modulation by non-hodgkin lymphoma in a patient with two primary intestinal T-cell lymphomas and long-standing celiac disease.

Tumors may influence immunologic reactions. Here, we report on a 72-year-old patient who suffered from celiac disease (CD) that had been diagnosed 20 years before. Under a normal diet but without any evidence of enteropathy or CD-associated antibodies, the patient developed a jejunal T-cell lymphoma. It was resected due to perforation and four courses of IMVP-16 were added. The patient started and kept a strict gluten-free diet (GFD). Two years later, he presented with weight loss and a clonally divergent refractory sprue type II with loss of antigen (CD8; T-cell receptor-beta) expression in intraepithelial lymphocytes. At this time point, he showed high titers of CD-associated antibodies, although he was on a strict GFD. This case report highlights several questions: the missing enteropathy under a gluten-containing diet supports the notion of immune suppression in malignant diseases, especially non-Hodgkin lymphoma. Secondly, the patient developed an early form of a second independent T-cell lymphoma (refractory sprue type II) under a strict GFD, then with CD-associated antibodies, which raises the question whether the clonal intraepithelial lymphocytes were stimulating antibody production. Thus, the single detection of CD-associated antibodies in patients with CD is not itself proof of noncompliance with GFD.

Calcifying fibrous tumor: an unrecognized IgG4--related disease?

Calcifying fibrous tumor is a rare benign mass lesion characterized by bland spindle cells embedded in abundant collagenous matrix, interspersed dystrophic or psammomatous calcifications, and lymphoplasmacytic infiltrate. It shares several clinical and morphologic features with IgG4-related disease, a newly recognized fibroinflammatory disorder. Characteristic histologic features of IgG4-related lesions include dense fibrosis and abundant lymphoplasmacytic infiltrate, similar to calcifying fibrous tumor. They contain high numbers of IgG4-positive plasma cells in the tissue. Patients also often have elevated serum IgG4 levels. We report the case of a patient with an ileal calcifying fibrous tumor that contained 69 IgG4-positive plasma cells per high-power field and an IgG4-to-IgG ratio of 56% in lesional plasma cells. The patient's serum IgG4 level was 185 mg/dL, more than double the normal value. Altogether, these features suggest that calcifying fibrous tumor could be an unrecognized lesion of IgG4-related disease.

Functional CCR9 expression is associated with small intestinal metastasis.

In general, metastases to the small intestine are rare, and mostly occur in melanoma. CCR9 has been shown to be the principal chemokine receptor for the thymus expressed chemokine (TECK), a chemokine selectively expressed in the small intestine and thymus. Here we show that CCR9 is highly expressed on melanoma cells and all melanoma cell lines isolated from small intestinal metastases, and on a proportion of cell lines from other sites. Only melanoma cells and cell lines from small intestinal metastases, however, were responsive to the CCR9 ligand TECK, as assessed by receptor downregulation and by actin polymerization. CCR9 expression was also found on the adenocarcinoma cell line CaCo-2 expressing characteristics of enterocytic differentiation, but not on any other cell line isolated from colorectal, breast, and lung cancer. Our data provide evidence that the aberrant functional cell surface expression of an organ-specific chemokine receptor is associated with metastasis to this site. The regulation of receptor function seems to be a critical step in the metastatic process.

Synchronous occurrence of carcinoid tumour of the appendix and T-cell lymphoma of the ileum. A case report with review of the literature.

Carcinoid tumours of the gastrointestinal tract are often associated with other tumour types at various sites. However, only rarely has a lymphoma constituted the second tumour. In the present paper, we report the case of a 62-year-old woman who was operated on for a perforated T-cell lymphoma of the ileum and in whom an appendicular carcinoid tumour was incidentally discovered at surgery. It was possible to completely remove both tumours and postoperatively the patient underwent CHOP treatment. Ten months after surgery the patient is well, with no tumour manifestations. We also discuss problems concerning classification of the lymphoma on account of loss of the T-cell antigen CD45RO (UCHL-1).

Genetic control of the resistance to spontaneous immunocytoma (plasmacytoma-IR tumour) development in LOU/C rats.

Immunocytomas (immunoglobulin secreting tumours) appear with a highly spontaneous incidence in animals of the inbred LOU/C strain but never in those of the inbred OKA strain. Congenic rats with LOU/C genetic background, having either the heavy or the kappa light immunoglobulin chain loci from the OKA strain, have an immunocytoma incidence similar to that of the LOU/C strain. The congenic strain, having the major histocompatibility complex of the OKA strain on the LOU/C background, showed no immunocytoma incidence. These results indicate that the MHC locus of the rat, or a gene closely linked to it, determines resistance to immunocytoma development. Specific chromosomal translocation associated with Ig gene chromosome and c-myc play a major role in the origin of the rat IR tumours. These experiments show that the resistance of the OKA strain to the appearance of IR tumours is not correlated with special properties of Ig heavy and kappa gene segments.

T-lymphoblastic lymphoma arising in the small intestine.

The authors report the clinical, pathological and immunological features of a case of T-lymphoblastic lymphoma presenting with protein-losing enteropathy. There was extensive multifocal involvement of the duodenum, jejunum and ileum. The mediastinum was not enlarged; the peripheral blood picture and bilateral bone marrow trephine biopsies were unremarkable. The tumor cells were positive for terminal deoxynucleotide transferase, CD3, CD2, CD7 and CD10; they were negative for CD1, CD5, CD4, CD8 and HLA-DR. The immunophenotype was that of an immature thymic T-cell. Monocytic and B-cell markers were negative. Despite initial dose reduction in chemotherapy, the patient still developed massive intestinal hemorrhage and succumbed 2 wks after treatment. Postmortem examination confirmed absence of thymic involvement. The overall picture strongly suggests a primary intestinal origin of this T-lymphoblastic lymphoma which contradicts the conventional wisdom that T-lymphoblastic lymphoma arises in the thymus from primitive cortical lymphocytes before rapidly disseminating.

Single jejunoileal and right colonic carcinoids as midgut tumors. A study collating immunophenotypes and histogenesis.

The jejunoileum and the right colon, both of which are located in the midgut, have some histologic similarities such as the presence of Paneth cells and intraepithelial endocrine cells (IEECs). Since gastrointestinal (GI) carcinoids arise from the same stem cells as GI endocrine cells, the question was whether or not there might also be similarities in the histogenesis of jejunoileal carcinoids (JICs) and right colonic carcinoids (RCCs). Ten single JICs and 3 RCCs together with their respective controls were stained using various neurohormonal immunoreagents. Our results showed that neither the JICs nor the RCCs appeared to arise from a background of diffuse IEEC hyperplasia. Furthermore, in the jejunoileum, serotonergic progenitor cells appear to have a proclivity for neoplastic transformation, as do cells of the pancreatic polypeptide and glucagon lineage in the right colon.

Occurrence and expression of cytokeratins in carcinoid tumours of the gastrointestinal tract and their probable precursor cells.

Occurrence and expression of cytokeratins were studied by the immunoperoxidase-antiperoxidase (PAP) technique in formalin-fixed, paraffin embedded material from 18 cases of carcinoid tumours of the gastrointestinal tract. Polyclonal antikeratin for wide spectrum screening was detected in 12 cases; low molecular weight cytokeratins, C19 and CAM5.2 were positive in majority of the cases whereas antikeratins for high molecular weight were negative in all. Similar positive immuno-reactivity with antibodies to cytokeratins were detected in the surrounding epithelial cells. These results suggest that carcinoids of the gastrointestinal tract originate from the endodermal stem cell and differentiates along one or more directions, and the immunohistochemical findings depend upon the direction of their differentiation.

[The clinicopathological and immunophenotypical features of 162 cases of gastrointestinal stromal tumor].

OBJECTIVE: To demonstrate the clinicopathological and immunophenotypical features of gastrointestinal stromal tumor (GIST). METHODS: One hundred and sixty-two cases of GIST were retrospectively studied. Among them, forty-six cases were immunostained using antibodies against vimentin, CD34, muscle specific actin (MSA), smooth muscle actin (SMA), neuron specific enolase(NSE), S-100 protein, synaptophysin (SYN), cytokeratin(CK), CEA, LCA. RESULTS: Clinically, male patients predominated with a male to female ratio of 3.8:1. The average age was 50 (range 6-74). The most common symptoms were gastrointestinal bleeding and abdominal mass in 45% and 39% of the cases, respectively. The common anatomical locations were stomach (43%), ileum (20%), jejunum (18%). Pathologically, all the tumor arose from the muscular layer. The tumor diameter varied from 0.5 to 43 cm. In 55% of the cases, the tumor was malignant. The main component cell types were spindle and epithelioid in appearance. Immunophenotypically, percentage of positivity for the 10 antibodies was as follows: vimentin, 100% (39/39), CD34, 64% (23/36), MSA, 47% (16/34), SMA, 41% (14/34), NSE, 61% (17/28), S-100 protein, 19% (4/21), SYN, 15% (3/20), CK, CEA, and LCA were negative. CONCLUSION: GIST is the most common mesenchymal tumor of the gastrointestinal tract. Immunostaining confirms that only some of the GIST shows partial differentiation toward smooth muscle, neuron, or both.

Overrepresentation of HLA-DQ2 in small intestinal neuroendocrine tumor patients.

PURPOSE: To investigate whether celiac disease risk haplotypes HLA-DQ2 and DQ8 also increase the risk for developing small intestinal neuroendocrine tumor (SI-NET). METHODS: Thirty-five patients with serotonin-producing jejunal and ileal SI-NET were examined with HLA-DQ genotyping and serology for IgA anti-tissue transglutaminase (tTG) antibodies. RESULTS: Twenty-one patients (60 %) carried HLA-DQ2 or DQ8, twice the frequency of the general population (P < 0.001). In particular DQ2 was overrepresented (P = 0.013). Gender, age, disease stage, histopathological grade, or multifocality of primary tumor did not differ between patients with DQ2 or DQ8 and patients with other HLA-DQ haplotypes. No patient in the study was diagnosed with celiac disease (latent or symptomatic) as anti-tTG antibodies were negative in all 35. CONCLUSION: HLA-DQ haplotypes associated with celiac disease are overrepresented also in patients with SI-NET, in particular HLA-DQ2.

The immune response to sporadic colorectal cancer in a novel mouse model.

Current mouse models do not reflect the sporadic nature of colon cancer and do not allow the analysis of antitumor immune response because of the lack of known tumor-specific antigens. Two transgenic mouse models with spontaneous tumor development were generated, directing the expression of SV40T antigen (Tag) either constitutively (Vil-Cre × LoxP-Tag-transgenic mice) or stochastically (Vil-Cre-ER(T2) × LoxP-Tag-transgenic mice) into the putative stem cell region of the crypt of Lieberkühn. Tumor development and antitumor immune response were monitored. Vil-Cre × LoxP-Tag mice developed multiple adenocarcinomas of the small intestine and colon at an average age of 6 months. During the tumor development, Tag-specific immunoglobulin G (IgG) antibodies were induced in half of the mice, although they had developed neonatal cytotoxic T lymphocyte (CTL) tolerance. This model shows similarity to hereditary colon cancer but not to the sporadic tumor development. Therefore, the conditional Vil-Cre-ER(T2) × LoxP-Tag mice were established, in which expression of the dormant Tag was induced by stochastic, tissue-specific activation of Cre recombinase. These mice spontaneously developed highly invasive, metastasizing colon carcinomas at an average age of 20 months. Colon carcinomas expressed epithelial and/or neuroendocrine markers depending on the grade of differentiation. Young Vil-Cre-ER(T2) × LoxP-Tag mice had retained CTL responses against epitope IV of Tag. The tumors induced strong anti-Tag IgG responses. We report, for the first time, a mouse model based on stochastic, tissue-specific activation of a dormant oncogene in the colon allowing the analysis of antitumor immune response against primary colorectal cancer.