Prognostic impact of nodal status and lymphovascular invasion in patients undergoing neoadjuvant chemotherapy for esophageal squamous cell carcinoma.

Nodal status is well known to be the most important prognostic factor for esophageal cancer patients, even if they are treated with neoadjuvant therapy. To establish an optimal postoperative adjuvant strategy for patients, we aimed to more accurately predict the prognosis of patients and systemic recurrence by using clinicopathological factors, including nodal status, in patients with esophageal cancer who received neoadjuvant chemotherapy. The clinicopathological factors associated with survival and systemic recurrence were investigated in 488 patients with esophageal squamous cell carcinoma who received neoadjuvant chemotherapy. Overall survival differed according to tumor depth, nodal status, tumor regression, and lymphovascular (LV) invasion. In the multivariate analysis, nodal status and LV invasion were identified as independent prognostic factors (P < 0.0001, P = 0.0008). Nodal status was also identified as an independent factor associated with systemic recurrence, although LV invasion was a borderline factor (P = 0.066). In each pN stage, patients with LV invasion showed significantly worse overall survival than those without LV invasion (pN0: P = 0.036, pN1: P = 0.0044, pN2: P = 0.0194, pN3: P = 0.0054). Patients with LV invasion were also more likely to have systemic, and any recurrence than those without LV invasion in each pN stage. Pathological nodal status and LV invasion were the most important predictors of survival and systemic recurrence in patients with esophageal cancer who underwent neoadjuvant chemotherapy followed by surgery. This finding could provide useful information about selecting candidates for adjuvant therapy among these patients. Our analysis showed that LV invasion was an independent prognostic factor in patients with esophageal cancer who underwent neoadjuvant chemotherapy and that combining LV invasion with pathological nodal status makes it possible to stratify the prognosis in those patients.

Development of an Immunochromatography Assay (QuickNavi-Ebola) to Detect Multiple Species of Ebolaviruses.

The latest outbreak of Ebola virus disease (EVD) in West Africa has highlighted the urgent need for the development of rapid and reliable diagnostic assays. We used monoclonal antibodies specific to the ebolavirus nucleoprotein to develop an immunochromatography (IC) assay (QuickNavi-Ebola) for rapid diagnosis of EVD. The IC assay was first evaluated with tissue culture supernatants of infected Vero E6 cells and found to be capable of detecting 103-104 focus-forming units/mL of ebolaviruses. Using serum samples from experimentally infected nonhuman primates, we confirmed that the assay could detect the viral antigen shortly after disease onset. It was also noted that multiple species of ebolaviruses could be detected by the IC assay. Owing to the simplicity of the assay procedure and absence of requirements for special equipment and training, QuickNavi-Ebola is expected to be a useful tool for rapid diagnosis of EVD.

Identification of an actin-binding site in p47phox an organizer protein of NADPH oxidase.

Actin has been reported to enhance the superoxide-generating activity of neutrophil NADPH oxidase in a cell-free system and to interact with p47phox, a regulatory subunit of the oxidase. In the present study, we searched for an actin-binding site in p47phox by far-western blotting and blot-binding assays using truncated forms of p47phox. The amino-acid sequence 319-337 was identified as an actin-binding site, and a synthetic peptide of this sequence bound to actin. The sequence shows no homology to other known actin-binding motifs. It is located in the autoinhibitory region of p47phox and includes Ser-328, a phosphorylation site essential for unmasking. Although a phosphorylation-mimetic p47phox mutant bound to actin with a lower affinity than the wild type, the same mutant interacted with filamentous actin more efficiently than the wild type. A mutant peptide p47phox (319-337, Ser328Glu) bound to filamentous actin more tightly than to monomer actin. These results suggest that p47phox moves to cortical actin when it becomes unmasked in the cells.

Identification of a short highly conserved amino acid sequence as the functional region required for posttranscriptional autoregulation of the cystathionine gamma-synthase gene in Arabidopsis.

Cystathionine gamma-synthase (CGS) catalyzes the first committed step of Met biosynthesis in plants. We have previously shown that expression of the gene for CGS is feedback-regulated at the level of mRNA stability, and that the amino acid sequence encoded by the first exon of the CGS gene itself is responsible for the regulation (Chiba, Y., Ishikawa, M., Kijima, F., Tyson, R. H., Kim, J., Yamamoto, A., Nambara, E., Leustek, T., Wallsgrove, R. M., and Naito, S. (1999) Science 286, 1371-1374). To identify the functional region within CGS exon 1, deletion analysis was performed. The results showed that the 41-amino acid region of exon 1 highly conserved among plants is necessary and sufficient for the regulation. Analyses of in vivo and in vitro generated mutations that abolish the regulation identified the functionally important amino acids as 11-13 residues within this conserved region. The importance of these residues was confirmed by deletion analysis within the conserved region. These studies identified the functional region of CGS exon 1 required for the posttranscriptional autoregulation of the CGS gene as (A)RRNCSNIGVAQ(I), with uncertainty of the first and last residues. This sequence is almost perfectly conserved among CGS sequences of higher plants but cannot be found elsewhere in the public databases.