Pan-Cancer Analyses Reveal Oncogenic and Immunological Role of PLOD2.

Some previous studies have shown that PLOD2 has some value in tumorigenesis. However, the broad significance of PLOD2 has not been discussed in depth. This study was aimed at elaborated and summarized the value of PLOD2 in various tumors. First, we integrated GTEx, The Cancer Genome Atlas and Cancer Cell Line Encyclopedia databases to analyze the expression of PLOD2, and found that it was expressed differently in normal tissues and significantly highly expressed in most tumors compared with normal tissues. Second, our analysis revealed that PLOD2 expression was negatively correlated with the prognosis of several tumors. For gastric cancer, the median overall survival time was significantly higher in the PLOD2 low expression group [HR 0.616 (95%CI 0.442-0.858), p = 0.004]. Third, for tumor immunity, PLOD2 was significantly associated with tumor infiltration, including immune infiltrating cells; immune checkpoint expression; immune microenvironment scores (immune score, stromal score and estimate scores); immunotherapy-related scores (tumor mutational burden, microsatellite instability, tumor neoantigen burden); expression of DNA repair genes Mismatch Repairs and methyltransferase; and enrichment analyses identified PLOD2-associated terms and pathways. Lastly, twenty pairs of gastric cancer and adjacent immunohistochemistry showed that PLOD2 was significantly overexpressed in gastric cancer (p < 0.001). Collectively, PLOD2 played a significant role in tumorigenesis and maybe serve as a potential biomarker for diagnosis and prognosis in cancers.

NKG2D Enhances Double-Negative T Cell Regulation of B Cells.

Numerous studies reported a small subpopulation of TCRαß+CD4-CD8- (double-negative) T cells that exert regulatory functions in the peripheral lymphocyte population. However, the origin of these double-negative T (DNT) cells is controversial. Some researchers reported that DNT cells originated from the thymus, and others argued that these cells are derived from peripheral immune induction. We report a possible mechanism for the induction of nonregulatory CD4+ T cells to become regulatory double-negative T (iDNT) cells in vitro. We found that immature bone marrow dendritic cells (CD86+MHC-II- DCs), rather than mature DCs (CD86+MHC-II+), induced high levels of iDNT cells. The addition of an anti-MHC-II antibody to the CD86+MHC-II+ DC group significantly increased induction. These iDNT cells promoted B cell apoptosis and inhibited B cell proliferation and plasma cell formation. A subgroup of iDNT cells expressed NKG2D. Compared to NKG2D- iDNT cells, NKG2D+ iDNT cells released more granzyme B to enhance B cell regulation. This enhancement may function via NKG2D ligands expressed on B cells following lipopolysaccharide stimulation. These results demonstrate that MHC-II impedes induction, and iDNT cells may be MHC independent. NKG2D expression on iDNT cells enhanced the regulatory function of these cells. Our findings elucidate one possible mechanism of the induction of peripheral immune tolerance and provide a potential treatment for chronic allograft rejection in the future.

Cyclooxygenase-2 expressed hepatocellular carcinoma induces cytotoxic T lymphocytes exhaustion through M2 macrophage polarization.

OBJECTIVE: Due to the tumor immune microenvironment (TIME) complexity and cancer heterogeneity, the clinical outcomes of hepatocellular carcinoma (HCC) are barely elicited from the conventional treatment options, even from the promising anti-cancer immunotherapy. As a suppressive TIME-related marker, the role played by cyclooxygenase-2 (COX-2) in HCC TIME, and its potential effects on anti-cancer T cell immune response remains unknown. In our study, to investigate the COX-2-dependent immune regulation pathway, we verified that the macrophages phenotypes were correlated to COX-2/PGE2 expressions among HCC patients. A multi-cellular co-culture platform containing HCC cells, macrophages, and T cells were established to mimic HCC TIME in vitro and in animal model. M2 macrophage polarization and activated CD8+ T cells exhaustion were observed under high COX-2 levels in HCC cells, with further evaluation using CRISPR/Cas9-based PTGS2 knocking out and COX-2 blockade (celecoxib) treatment controls. PGE2, TGF-ß, Granzyme B, and IFN-γ levels were testified by flow cytometry and ELISA to fully understand the mechanism of COX-2 suppressive effects on T cell-based anti-HCC responses. The activation of the TGF-ß pathway evaluated by auto-western blot in T cells was confirmed which increased the level of phosphorylated Smad3, phosphorylated Samd2, and FoxP1, leading to T cell de-lymphotoxin. In conclusion, high COX-2-expressing HCC cell lines can induce anti-tumor abilities exhaustion in activated CD8+ T cell through M2 TAMs polarization and TGF beta pathway. COX-2 inhibitors may reduce the inhibitory effect on CD8+ T cells through regulating TAMs in TIME, thus enhance the T cell-based cytotoxicity and improve the prognosis of HCC patients.

TIGIT Can Exert Immunosuppressive Effects on CD8+ T Cells by the CD155/TIGIT Signaling Pathway for Hepatocellular Carcinoma In Vitro.

The efficacy of adoptive cellular immunotherapy against cancer cells is limited due to the presence of immunosuppressive cells within the solid tumor microenvironment. The upregulation of certain coinhibitory receptors may lead to exhaustion of the immune effector cells. T-cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT) is an immune inhibitory receptor expressed by regulatory T cells and activated T cells and natural killer cells. The aim of this study was to determine the immunosuppressive effects of CD155/TIGIT signaling on CD8 T cells of adoptive cellular immunotherapy in hepatocellular carcinoma (HCC). Our studies found that CD155 was overexpressed in HCC, and CD155 HCC cells upregulated TIGIT on CD8 T cells, which decreased the secretion of interferon-γ, tumor necrosis factor-α, and interleukin-17A and increased that of interleukin-10 from the effector cells. However, TIGIT blockade or CD155-knockdown reversed the inhibitory effect of HCC cells on CD8 T-cell effector function. These results indicate that TIGIT can exert an immunosuppressive effect on CD8 T cells by modulating cytokine production through CD155, and is a promising target to optimize adoptive cellular immunotherapy against HCC.

Hedgehog signaling promotes sorafenib resistance in hepatocellular carcinoma patient-derived organoids.

BACKGROUND: The mechanism underlying sorafenib resistance in hepatocellular carcinoma (HCC) remains unclear. Accumulating evidence suggests that tumor-initiating cells (TICs) are a pivotal driving force. Both CD44 and Hedgehog signaling play crucial roles in TIC properties in HCC. In this study, we explored the roles of CD44 and Hedgehog signaling in sorafenib resistance and evaluated the therapeutic effect of cotreatment with sorafenib and Hedgehog signaling inhibitors in HCC patient-derived organoid (PDO) models to improve treatment efficacy. METHODS: We collected HCC specimens to establish PDO models. Cell viability and malignant transformation properties were investigated after treatment with different TIC-related inhibitors alone or in combination with sorafenib to evaluate the therapeutic effect in PDOs and cell lines by in vitro and in vivo experiments. Expression levels of Hedgehog signaling proteins and CD44 were monitored to reveal potential relationships. RESULTS: We demonstrated that our HCC PDO models strongly maintained the histological features of the corresponding tumors and responded to drug treatment. Furthermore, CD44-positive HCC PDOs were obviously resistant to sorafenib, and sorafenib increased CD44 levels. A drug screen showed that compared with Notch, Hippo and Wnt signaling inhibitors, a Hedgehog signaling inhibitor (GANT61) potently suppressed HCC PDO cell viability. In addition, there was a highly synergistic effect in vitro and in vivo on the suppression of cell viability and malignant properties when sorafenib and GANT61 were added to CD44-positive HCC PDOs and cell lines, respectively. Furthermore, the upregulation of CD44 and Hedgehog signaling induced by sorafenib was reversed by GANT61. CONCLUSIONS: GANT61 significantly suppressed Hedgehog signaling to reverse sorafenib resistance in CD44-positive HCC. The combination of sorafenib and Hedgehog signaling inhibitors might be effective in HCC patients with high CD44 levels as a personalized-medicine approach.

Surgical treatment of intrahepatic cholangiocarcinoma: a retrospective study of 104 cases.

OBJECTIVE: To explore the clinicopathological features, surgical treatment techniques, and prognostic risk factors of intrahepatic cholangiocarcinoma (ICC). METHODS: A total of 104 ICC cases were collected from January 2008 to December 2013 at Tianjin Medical University Cancer Institute and Hospital and divided into the hepatic hilum lymphadenectomy (HLL, 21 cases), extended hepatic hilum lymphadenectomy (EHLL, 12 cases), and non-lymphadenectomy (NL, 71 cases) groups. The clinical data of the patients were retrospectively analyzed, and the prognostic differences were compared among different groups. RESULTS: The 1-, 2-, and 3-year overall survival (OS) rates of all cases were 72.1%, 56.1%, and 43.7%, respectively. The median survival duration was 34 months. The 1-, 2-, and 3-year OS rates of the HLL group (42.9%, 28.6%, and 28.6%, respectively) were significantly lower than those of the NL group (78.9%, 62.5%, and 47.8%, respectively). Meanwhile, the 1-, 2-, and 3-year OS rates of the EHLL group (75.0%, 56.1%, and 33.3%, respectively) were not significantly different from those of the other two groups. Univariate analysis showed that age, gender, American Joint Committee on Cancer (AJCC) stage, differentiation, ferritin (Fer), carbohydrate antigen19-9 (CA19-9) and carcinoembryonicantigen (CEA) levels, lymph node metastasis (LNM), and lymph node dissection (LND) were prognostic factors for the long-term survival of ICC. Meanwhile, multivariate analysis revealed that age, AJCC stage, differentiation, Fer levels, and LNM were independent risk factors for survival. CONCLUSIONS: ICC patients will not benefit from lymphadenectomy in the absence of LNM. However, systematic lymphadenectomy may improve ICC outcomes if the location of lymphatic metastasis is known. Age, AJCC stage, differentiation, Fer level, and LNM are independent risk factors for survival in ICC.

Spiking voltages for faster switching of nematic liquid-crystal light modulators.

Electrical address circuits developed for driving fast-switching ferroelectric liquid-crystal spatial light modulators (SLM) can be programmed to increase the speed of much slower responding nematic liquid-crystal SLMs. Using an addressing circuit that can switch as fast as 0.164 ms, voltages are programmed for values of phase that exceed the desired phase, and when the phase reaches the desired value, the voltage is switched to the required steady-state voltage. For a SLM that has a phase range of 3.5pi and that is programmed over a 2pi range, switching speed is reduced from 400 ms to between 71 and 77 ms. The speedup algorithm is applied to each pixel of the SLM together with a digital correction for a spatially nonuniform phase.

Phase calibration of spatially nonuniform spatial light modulators.

A new 512 x 512 pixel phase-only spatial light modulator (SLM) has been found to deviate from being flat by several wavelengths. Also, the retardation of the SLM relative to voltage varies across the device by as much as 0.25 wavelength. The birefringence of each pixel as a function of address voltage is measured from the intensity of the SLM between crossed polarizers. To these responses are added a reference spatial phase measured by phase shifting interferometry for a single address voltage. Fits to the measured data facilitate the compensation of the SLM to a root-mean-square wave-front error of 0.06 wavelength. The application of these corrections to flatten the full aperture of the SLM sharpens the focal plane spot and reduces the distortion of computer-designed diffraction patterns.

System for demonstrating arbitrary multi-spot beam steering from spatial light modulators.

A graphical user interface is used to program sequences of analog phase patterns onto a 512 x 512 pixel, electrically-addressed spatial light modulator (SLM). Hand sketches made with a digital pen are used to prescribe the footprints, velocities and trajectories of multiple, independently-controlled diffracted spots. The interface is intended to demonstrate to potential end-users, who are not knowledgeable about diffractive optical design, to what degree SLM's may be considered to produce arbitrary multi-spot beam steering. Using the interface, scanning sequences are created, programmed, run through, and diffracted from a SLM that simultaneously scans multiple patterns on distinct trajectories.

Estimation of thermal coefficients of magneto-optical media.

Previously we described a method for estimating the thermal conductivity of magneto-optic recording media. The method relies on identifying the laser power that brings the maximum temperature of the TbFeCo layer to as high as the Curie temperature. We extensively use a similar method to estimate the heat capacity of a dielectric layer, a TbFeCo layer, and an aluminum alloy layer of magneto-optic recording media. Measurements are conducted on static disks with a beam of light focused on a TbFeCo layer. The method has the advantage of thermal diffusion depending on a multilayer structure and irradiation time.