Small-cell lung cancer (SCLC) is an aggressive, rapidly metastasizing neoplasm. The chemokine stromal cellderived factor-1 (SDF-1/CXCL12) is constitutively secreted by marrow stromal cells and plays a key role for homing of hematopoietic cells to the marrow. Here, we report that tumor cells from patients with SCLC express high levels of functional CXCR4 receptors for the chemokine CXCL12. Reverse transcriptase-polymerase chain reaction and flow cytometry demonstrated CXCR4 mRNA and CXCR4 surface expression in SCLC cell lines. Immunohistochemistry of primary tumor samples from SCLC patients revealed high expression of CXCR4. CXCL12 elicited CXCR4 receptor endocytosis, actin polymerization, and a robust activation of phospho-p44/ 42 mitogen-activated protein kinase in SCLC cells. Furthermore, CXCL12 induced SCLC cell invasion into extracellular matrix and firm adhesion to marrow stromal cells. Stromal cell adhesion of SCLC cells was significantly inhibited by the specific CXCR4 antagonist T140, pertussis toxin, antivascular cell adhesion molecule-1(VCAM-1) antibodies, and CS-1 peptide, demonstrating the importance of CXCR4 chemokine receptor activation and a4b1 integrin binding, respectively. In addition, CXCL12 enhanced the adhesion of SCLC cells to immobilized VCAM-1, demonstrating that CXCR4 chemokine receptors can induce integrin activation on SCLC cells. As SCLC has a high propensity for bone marrow involvement, our findings suggest that CXCR4 chemokine receptors and a4b1 integrins play a critical role in the interaction of SCLC cells with stromal cells in the tumor microenvironment.
Aim-To classify ocular adnexal lymphomas according to the Revised European and American Lymphoma (REAL) classification and to determine any correlation between clinical features or histomorphological variables with the patients' outcome. Methods-Conventional and immunohistology were performed on representative sections of 53 specimens of 46 patients with ocular adnexal lymphoma. The antibodies used were CD20, BCL-2, CD21, CD23, CD43, CD3, CD5, p53, cyclin D1, pan-cytokeratin, kappa, lambda, IgD, and IgM. The growth fraction of the tumours was determined using the MIB-1 antibody directed against the Ki-67 antigen. Clinical follow up data regarding the outcome were obtained from the treating physicians and/or hospital files. The Student's t test and log rank test were used for statistical analysis. Results-The patient collective consisted of 29 females and 17 males with an age range of 32-89.7 years (average 63 years). Almost all specimens represented B cell non-Hodgkin's lymphomas: extranodal marginal zone lymphoma (EMZL) (n=38), diVuse large cell B cell lymphoma (n=8), lymphoplasmocytic lymphoma/immunocytoma (n=2), mantle cell lymphoma (n=2), follicle centre lymphoma (n=1), and plasmacytoma (n=1). One case of a secondary anaplastic large cell lymphoma of T cell type (T-ALCL) was diagnosed. The majority of the patients had stage I disease. A variety of therapeutic regimens was administered, the main form of treatment being radiotherapy. The average follow up time was 85 months. Complete remission was achieved in 24 patients (10 after excision alone, eight after radiotherapy alone, three after combined excision and radiotherapy, one after chemotherapy alone, and two after combined radiotherapy and chemotherapy). 12 patients died of causes related to lymphoma; in one patient the cause of death was unknown. Six patients had persistent tumour at final follow up and two patients were lost to follow up. The stage at presentation, as well as the lymphoma malignancy category, had a significant correlation with the final course of the disease (p=0.0001 and p=0.03, respectively). A significant correlation was also noted between the final outcome (p<0.05) and tumour cell expression for Ki-67 antigen and p53 protein.Conclusion-67% of patients with ocular adnexal lymphoma had EMZL. The stage at presentation had a significant influence on the final outcome. MIB-1 and p53 expression by the tumour cells proved to be important immunohistochemical markers concerning the prognosis. It is suggested that, following thorough staging investigations, primary EMZL (stage I) (if accessible) should be treated with excisional biopsy and subsequent low dose radiotherapy. Primary diVuse large cell B cell lymphoma of the ocular adnexa requires at least similar therapeutic measures and regular intensive follow up. (Br J Ophthalmol 2001;85:63-69)
The expression of mucin MUC2 was investigated in normal colonic tissue, in colonic adenomas and in carcinomas of the mucinous and non-mucinous type. The latter were subdivided into carcinomas originating from the adenoma-carcinoma sequence (ACS) and de novo (DN) carcinomas. The expression was assayed by immunohistochemistry with the monoclonal anti-MUC2 antibody CCP58 and by mRNA semiquantitation. MUC2 protein epitope CCP58 was strongly expressed in 21% of normal colonic tissues, in 40% of villous and in 48% of tubular adenomas. Mucinous carcinomas exhibited strong expression in 72%, ACS carcinomas in 21% and DN adenocarcinomas in none of the tumors investigated. Compared with the adjacent non-malignant tissue (transitional mucosa), CCP58 epitope expression in the tumor was higher in 74% of mucinous carcinomas, but equal or lower in 69% of ACS carcinomas and in 100% of de novo carcinomas. The alterations of MUC2 expression detected by immunohistochemistry in adenocarcinomas were confirmed on mRNA level. These data indicate that the MUC2 expression pattern is different in the 3 carcinoma types investigated. MUC2 over-expression occurs in the adenomatous tissue. It is always maintained in mucinous carcinomas, but frequently decreased in non-mucinous ACS carcinomas. DN carcinomas are most frequently associated with decreased expression of MUC2.
The 8p11 myeloproliferative syndrome (EMS) also known as stem cell leukemia-lymphoma syndrome (SCLL) is associated with translocations that disrupt FGFR1. The resultant fusion proteins are constitutively active tyrosine kinases, and different FGFR1 fusions are associated with subtly different disease phenotypes. We report here a patient with a t(8;17)(p11;q23) and an unusual myelodysplastic/myeloproliferative disease (MDS/MPD) characterized by thrombocytopenia due to markedly reduced size and numbers of megakaryocytes, with elevated numbers of monocytes, eosinophils and basophils. A novel mRNA fusion between exon 32 of the myosin XVIIIA gene (MYO18A) at chromosome band 17q11 and exon 9 of FGFR1 was identified. Partial characterization of the genomic breakpoints in combination of bubble-PCR with fluoresence in situ hybridization revealed that the t(8;17) arose from a threeway translocation with breaks at 8p11, 17q11 and 17q23. MYO18A-FGFR1 is structurally similar to other fusion tyrosine kinases and is likely to be the causative transforming lesion in this unusual MDS/MPD.
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