Circulating tumor cells (CTCs), defined as tumor cells circulating in the peripheral blood of patients with solid tumors, are relatively rare. Diagnosis using CTCs is expected to help in the decision-making for precision cancer medicine. We have developed an automated microcavity array (MCA) system to detect CTCs based on the differences in size and deformability between tumor cells and normal blood cells. Herein, we evaluated the system using blood samples from non-small-cell lung cancer (NSCLC) and small-cell lung cancer (SCLC) patients. To evaluate the recovery of CTCs, preclinical experiments were performed by spiking NSCLC cell lines (NCI-H820, A549, NCI-H23 and NCI-H441) into peripheral whole blood samples from healthy volunteers. The recovery rates were 70% or more in all cell lines. For clinical evaluation, 6 mL of peripheral blood was collected from 50 patients with advanced lung cancer and from 10 healthy donors. Cells recovered on the filter were stained. We defined CTCs as DAPI-positive, cytokeratin-positive, and CD45-negative cells under the fluorescence microscope. The 50 lung cancer patients had a median age of 72 years (range, 48–85 years); 76% had NSCLC and 20% had SCLC, and 14% were at stage III disease whereas 86% were at stage IV. One or more CTCs were detected in 80% of the lung cancer patients (median 2.5). A comparison of the CellSearch system with our MCA system, using the samples from NSCLC patients, confirmed the superiority of our system (median CTC count, 0 versus 11 for CellSearch versus MCA; p = 0.0001, n = 17). The study results suggest that our MCA system has good clinical potential for diagnosing CTCs in lung cancer.

Circulating tumor cells (CTCs) and their programmed death receptor-ligand 1 (PD-L1) expression in patients with lung cancer were detected using a microcavity array system. PD-L1 expression was detected in 73% of patients who harbored CTCs. The proportion of PD-L1-positive CTCs ranged from 3% to 100%, suggesting intra-patient heterogeneity. No correlation on PD-L1 expression was observed between tumor tissues and CTCs. Background: Blockade of the programmed death receptor-1 (PD-1) pathway is effective against solid tumors including lung cancer. PD-ligand 1 (PD-L1) expression on tumor tissue serves as a predictive biomarker for the efficacy of PD-1 pathway blockade. Here, we evaluated the expression of PD-L1 on circulating tumor cells (CTCs) in patients with lung cancer. Materials and Methods: Peripheral whole blood (3 mL) was collected from patients, and CTCs and PD-L1 expression were detected using a microcavity array (MCA) system. Immunohistochemistry for PD-L1 detection was also performed using matched tumor tissues. Results: Sixty-seven patients with lung cancer were enrolled in the study between July 2015 and April 2016 at Wakayama Medical University Hospital. The characteristics of the patients were as follows: median age, 71 years (range, 39-86 years); male, 72%; stage II to III/IV, 14%/85%; nonesmall-cell lung cancer/small-cell lung cancer/other, 73%/21%/6%. CTCs were detected in 66 of 67 patients (median, 19; range, 0-115), and more than 5 CTCs were detected in 78% of patients. PD-L1-expressing CTCs were detected in 73% of patients, and the proportion score of PD-L1-expressing CTCs ranged from 3% to 100%, suggesting intra-patient heterogeneity of PD-L1 expression on CTCs. Tumor tissues were available from 27 patients and were immunostained for PD-L1, and no correlation was observed between tumor tissues and CTCs based on the proportion score (R 2 ¼ 0.0103). Conclusion: PD-L1 expression was detectable on CTCs in patients with lung cancer, and intra-patient heterogeneity was observed. No correlation was observed between PD-L1 expression in tumor tissues and CTCs.

Excellent photoelectrical properties are reported for Mg-doped hydrogenated GaN (GaN:H) films grown at 380 °C. These films are fabricated using dual remote-plasma metalorganic chemical vapor deposition under hydrogen-rich conditions. Infrared spectra exhibit N–H and Ga–H vibration bands but not a Mg–H band. The spectral photoresponse of Al/Mg-doped GaN:H/Au sandwich-type cells reveals that the peak responsivity is 0.11 A/W at 360 nm with the dark current of 10−11 A at −1 V bias. The application in low-cost high-sensitivity visible blind ultraviolet sensors are exhibited for the films.

Hydrogenated amorphous and microcrystalline GaN films are grown by remote-plasma metalorganic chemical vapor deposition at a substrate temperature below 300°C. These films have a stoichiometric composition with 17 to 30 at% hydrogen. The films on aluminum exhibit a fast ultraviolet (UV) photoresponse with a photocurrent to dark current ratio of 104. The normalized photoconductivity, ηµτ of the film with E opt of 3.2 eV is of the order of 10-6 cm2·V-1. Photodegradation effects have never been observed even after 5 h of irradiation with intense UV light of 500 mW/cm2.

Electroluminescence (EL) from hydrogenated polycrystalline GaN surface light-emitting devices is reported for the first time. The devices consist of a simple sandwich-type cell of films grown at 380°C on indium-tin-oxide coated glass and Al substrates with an Au electrode. Pale yellow EL is observed at room temperature in a lighted room at wavelengths ranging from 450 nm to 700 nm with a peak at 570 nm. Luminance is 7 cd/m2 at an applied DC voltage of 7 V and a current of 35 mA.

Members of the SNARE protein family participate in the docking-fusion step of several intracellular vesicular transport events. Saccharomyces cerevisiae Vam7p was identified as a SNARE protein that acts in vacuolar protein transport and membrane fusion. However, in Schizosaccharomyces pombe, there have been no reports regarding the counterpart of Vam7p. Here, we found that, although the SPCC594.06c gene has low similarity to Vam7p, the product of SPCC594.06c has a PX domain and SNARE motif like Vam7p, and thus we designated the gene Sch. pombe vsl1 + (Vam7-like protein 1). The vsl1D cells showed no obvious defect in vacuolar protein transport. However, cells of the vsl1D mutant with a deletion of fsv1 + , which encodes another SNARE protein, displayed extreme defects in vacuolar protein transport and vacuolar morphology. Vsl1p was localized to the vacuolar membrane and prevacuolar compartment, and its PX domain was essential for proper localization. Expression of the fusion protein GFP-Vsl1p was able to suppress ZnCl 2 sensitivity and the vacuolar protein sorting defect in the fsv1D cells. Moreover, GFP-Vsl1p was mislocalized in a pep12D mutant and in cells overexpressing fsv1 + . Importantly, overexpression of Sac. cerevisiae VAM7 could suppress the sensitivity to ZnCl 2 of vsl1D cells and the vacuolar morphology defect of vsl1Dfsv1D cells in Sch. pombe. Taken together, these data suggest that Vsl1p and Fsv1p are required for vacuolar protein transport and membrane fusion, and they function cooperatively with Pep12p in the same membrane-trafficking step.

Nitride-based ultraviolet metal-semiconductor-metal photodetectors with low-temperature GaN cap layers and Ir ∕ Pt contact electrodes

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