We have investigated the role of antigen-processing machinery (APM) component defects in HLA class I antigen downregulation in laryngeal squamous cell carcinoma (SCC) lesions and assessed the clinical significance of these defects. To this end, 63 formalin-fixed, paraffin-embedded tumor lesions were examined for APM component and HLA class I antigen expression by immunohistochemistry. Calnexin, calreticulin, and ERp57 were down-regulated in f25% of the lesions tested, whereas LMP2, TAP1, tapasin, and HLA class I antigens were down-regulated in at least 70% of the lesions tested. LMP2 and tapasin expression was significantly correlated with HLA class I antigen expression suggesting APM component defects as a mechanism underlying HLA class I antigen downregulation in laryngeal SCC lesions. The expression of most APM components and HLA class I antigens was correlated with the extent of CD8 + T cell infiltration into tumor lesions. Furthermore, LMP2 and HLA class I antigen down-regulation and low CD8 + T cell infiltration were significantly associated with reduced patients' survival. Multivariate analysis identified HLA class I antigen down-regulation as an independent unfavorable prognostic marker. This association is likely to reflect the reduction in the extent of CD8 + T cell infiltration in laryngeal SCC lesions. (Cancer Res 2006; 66(18): 9281-9)

Human saliva chromogranin A (CgA) is clinically promising as a psychological stress marker. However, expression of CgA is poorly understood in humans, although salivary gland localization of CgA in other mammals, such as rodents and horses, has been demonstrated. In the present study, we investigated the expression and localization of CgA in the human submandibular gland (HSG) using various methods. CgA was consistently localized in serous and ductal cells in HSG, as detected by immunohistochemistry and in situhybridization. Reactivity was stronger in serous cells than in ductal cells. In addition, strong immunoreactivity for CgA was observed in the saliva matrix of ductal cavities. Western blotting gave one significant immunoreactive band of 68 kDa in the adrenal gland, HSG and saliva. Finally, CgA was detected in secretory granules of serous and ductal cells by immunoelectron microscopy. In conclusion, CgA in humans is produced by HSG and secreted into saliva.

The naphthalene-catabolic (nah) genes on the incompatibility group P-9 (IncP-9) self-transmissible plasmid NAH7 from Pseudomonas putida G7 are some of the most extensively characterized genetic determinants for bacterial aerobic catabolism of aromatic hydrocarbons. In contrast to the detailed studies of its catabolic cascade and enzymatic functions, the biological characteristics of plasmid NAH7 have remained unclear. Our sequence determination in this study together with the previously deposited sequences revealed the entire structure of NAH7 (82,232 bp). Comparison of NAH7 with two other completely sequenced IncP-9 catabolic plasmids, pDTG1 and pWW0, revealed that the three plasmids share very high nucleotide similarities in a 39-kb region encoding the basic plasmid functions (the IncP-9 backbone). The backbone of NAH7 is phylogenetically more related to that of pDTG1 than that of pWW0. These three plasmids carry their catabolic gene clusters at different positions on the IncP-9 backbone. All of the NAH7-specified nah genes are located on a class II transposon, Tn4655. Our analysis of the Tn4655-encoded site-specific recombination system revealed that (i) a novel tyrosine recombinase, TnpI, catalyzed both the intra-and intermolecular recombination between two copies of the attI site, (ii) the functional attI site was located within a 119-bp segment, and (iii) the site-specific strand exchange occurred within a 30-bp segment in the 41-bp CORE site. Our results and the sequence data of other naphthalene-catabolic plasmids, pDTG1 and pND6-1, suggest a potential role of the TnpI-attI recombination system in the establishment of these catabolic plasmids.

Nasal natural killer (NK)/T-cell lymphoma (NNKTL) is a clinical illness characterized by progressive unrelenting ulceration and necrosis of the nasal cavity and midline facial tissues. Histological features of the lymphoma include angiocentric and polymorphous lymphoreticular infiltrates, called polymorphic reticulosis. Surface antigens and the NK-cell marker, CD56, as well as pan-T antigen CD2, cytoplasmic CD3 (CD3epsilon), and CD45 are expressed in the lymphoma cells. The origin of the lymphoma is thought to be either NK-cell linkage without T-cell receptor (TCR) rearrangement or gammadeltaT-cell linkage with gammadeltaTCR rearrangement. Since the authors of this study first demonstrated the presence of Epstein Barr virus (EBV)-DNA and EBV oncogenic proteins in NNKTL, the lymphoma has been classified as one of the EBV-associated malignancies. The NNKTL cells produce interleukin (IL)-9, IL-10, and interferon-gamma-inducible protein-10 (IP-10), possibly due to EBV-oncogenic proteins in the lymphoma cells, and such cytokines take an important part in the cell proliferation and invasion, acting in an autocrine manner. Clinically, the serum EBV-DNA copy number is useful as a specific tumor marker and a predictive prognostic factor. Even in early clinical stages, the lymphoma shows poor prognosis caused by the rapid progression of the lesion into distinct organs. Our newly designed arterial infusion chemotherapy, from the superficial temporal artery, in combination with radiotherapy, has shown a favorable outcome in patients with NNKTL. In this article, the clinical, pathological, and virological characteristics of the lymphoma are reviewed, along with a report of our investigations.

Purpose: Nasal natural killer (NK)/T-cell lymphoma is associated with EBV and has distinct clinical and histologic features. However, little is known about its genetic features. In this study, we examined the genes expressed by SNK-6 and SNT-8 cells, which were established from nasal NK/T-cell lymphomas, and found that interleukin (IL)-9 was specifically expressed in these two cell lines. Experimental Design: cDNA array was used to examine the genes expressed by SNK-6 and SNT-8 cells. Expression of IL-9 and IL-9 receptor was investigated by reverse transcription-PCR, ELISA, and flow cytometry. Cell growth was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Immunohistologic staining and ELISA were used to examine IL-9 expression in biopsies and sera from patients, respectively. Results: In cDNA array, expression of IL-9 mRNA was much higher in SNK-6 and SNT-8 cells than in NK-92 cells from non-nasal NK-cell lymphoma and peripheral blood mononuclear cells from healthy volunteers. Furthermore, IL-9 was specifically expressed by SNK-6 and SNT-8 cells but not by other NK-cell, NK-likeT-cell, and T-cell lymphoma/leukemia cell lines. IL-9 receptor was also expressed on the surfaces of SNK-6 and SNT-8 cells. An IL-9-neutralizing antibody inhibited the growth of these two cell lines, whereas recombinant human IL-9 enhanced their growth. Most significantly, IL-9 was present in biopsies and sera from patients with this lymphoma. Conclusions:These results suggest that IL-9 plays an important role innasal NK/T-cell lymphoma possibly via an autocrine mechanism.