Ribosomal Protein L9 Maintains Stemness of Colorectal Cancer via an ID-1 Dependent Mechanism.

The identification of therapeutic target genes that are functionally involved in stemness is crucial to effectively cure patients with metastatic carcinoma. We have previously reported that inhibition of ribosomal protein L9 (RPL9) expression suppresses the growth of colorectal cancer (CRC) cells by inactivating the inhibitor of DNA-binding 1 (ID-1) signaling axis, which is functionally associated with cancer cell survival. In addition to cell proliferation, ID-1 is also involved in the maintenance of cancer stemness. Thus, we aimed in this study to investigate whether the function of RPL9 could correlate with CRC stem cell-like properties. Here, we demonstrated that siRNA silencing of RPL9 reduced the invasiveness and migrative capabilities of HT29 and HCT116 parental cell populations and the capacity for sphere formation in the HT29 parental cell population. CD133+ cancer stem cells (CSCs) were then separated from CD133- cancer cells of the HT29 parental cell culture and treated with RPL9-specific siRNAs to verify the effects of RPL9 targeting on stemness. As a result, knockdown of RPL9 significantly suppressed the proliferative potential of CD133+ colorectal CSCs, accompanied by a reduction in CD133, ID-1, and p-IκBα levels. In line with these molecular alterations, targeting RPL9 inhibited the invasion, migration, and sphere-forming capacity of CD133+ HT29 CSCs. Taken together, these findings suggest that RPL9 promotes CRC stemness via ID-1 and that RPL9 could be a potential therapeutic target for both primary CRC treatment and the prevention of metastasis and/or recurrence.

Regulation of Betaine Homocysteine Methyltransferase by Liver Receptor Homolog-1 in the Methionine Cycle.

Betaine-homocysteine S-methyltransferase (BHMT) is one of the most abundant proteins in the liver and regulates homocysteine metabolism. However, the molecular mechanisms underlying Bhmt transcription have not yet been elucidated. This study aimed to assess the molecular mechanisms underlying Bhmt transcription and the effect of BHMT deficiency on metabolic functions in the liver mediated by liver receptor homolog-1 (LRH-1). During fasting, both Bhmt and Lrh-1 expression increased in the liver of Lrh-1f/f mice; however, Bhmt expression was decreased in LRH-1 liver specific knockout mice. Promoter activity analysis confirmed that LRH-1 binds to a specific site in the Bhmt promoter region. LRH-1 deficiency was associated with elevated production of reactive oxygen species (ROS), lipid peroxidation, and mitochondrial stress in hepatocytes, contributing to hepatic triglyceride (TG) accumulation. In conclusion, this study suggests that the absence of an LRH-1-mediated decrease in Bhmt expression promotes TG accumulation by increasing ROS levels and inducing mitochondrial stress. Therefore, LRH-1 deficiency not only leads to excess ROS production and mitochondrial stress in hepatocytes, but also disrupts the methionine cycle. Understanding these regulatory pathways may pave the way for novel therapeutic interventions against metabolic disorders associated with hepatic lipid accumulation.

Theoretical efficiency limit of diffractive input couplers in augmented reality waveguides.

Considerable efforts have been devoted to augmented reality (AR) displays to enable the immersive user experience in the wearable glasses form factor. Transparent waveguide combiners offer a compact solution to guide light from the microdisplay to the front of eyes while maintaining the see-through optical path to view the real world simultaneously. To deliver a realistic virtual image with low power consumption, the waveguide combiners need to have high efficiency and good image quality. One important limiting factor for the efficiency of diffractive waveguide combiners is the out-coupling problem in the input couplers, where the guided light interacts with the input gratings again and get partially out-coupled. In this study, we introduce a theoretical model to deterministically find the upper bound of the input efficiency of a uniform input grating, constrained only by Lorentz reciprocity and energy conservation. Our model considers the polarization management at the input coupler and can work for arbitrary input polarization state ensemble. Our model also provides the corresponding characteristics of the input coupler, such as the grating diffraction efficiencies and the Jones matrix of the polarization management components, to achieve the optimal input efficiency. Equipped with this theoretical model, we investigate how the upper bound of input efficiency varies with geometric parameters including the waveguide thickness, the projector pupil size, and the projector pupil relief distance. Our study shines light on the fundamental efficiency limit of input couplers in diffractive waveguide combiners and highlights the benefits of polarization control in improving the input efficiency.

RPL27 contributes to colorectal cancer proliferation and stemness via PLK1 signaling.

Although expression of ribosomal protein L27 (RPL27) is upregulated in clinical colorectal cancer (CRC) tissue, to the best of our knowledge, the oncogenic role of RPL27 has not yet been defined. The present study aimed to investigate whether targeting RPL27 could alter CRC progression and determine whether RPL27 gains an extra­ribosomal function during CRC development. Human CRC cell lines HCT116 and HT29 were transfected with RPL27­specific small interfering RNA and proliferation was assessed in vitro and in vivo using proliferation assays, fluorescence­activated cell sorting (FACS) and a xenograft mouse model. Furthermore, RNA sequencing, bioinformatic analysis and western blotting were conducted to explore the underlying mechanisms responsible for RPL27 silencing­induced CRC phenotypical changes. Inhibiting RPL27 expression suppressed CRC cell proliferation and cell cycle progression and induced apoptotic cell death. Targeting RPL27 significantly inhibited growth of human CRC xenografts in nude mice. Notably, polo­like kinase 1 (PLK1), which serves an important role in mitotic cell cycle progression and stemness, was downregulated in both HCT116 and HT29 cells following RPL27 silencing. RPL27 silencing reduced the levels of PLK1 protein and G2/M­associated regulators such as phosphorylated cell division cycle 25C, CDK1 and cyclin B1. Silencing of RPL27 reduced the migration and invasion abilities and sphere­forming capacity of the parental CRC cell population. In terms of phenotypical changes in cancer stem cells (CSCs), RPL27 silencing suppressed the sphere­forming capacity of the isolated CD133+ CSC population, which was accompanied by decreased CD133 and PLK1 levels. Taken together, these findings indicated that RPL27 contributed to the promotion of CRC proliferation and stemness via PLK1 signaling and RPL27 may be a useful target in a next­generation therapeutic strategy for both primary CRC treatment and metastasis prevention.

Clinical Characteristics of TZAP (ZBTB48) in Hepatocellular Carcinomas from Tissue, Cell Line, and TCGA.

Background and Objectives: ZBTB48 is a telomere-related protein that has been renamed telomeric zinc finger-associated protein (TZAP). It favorably binds to elongated telomeres to regulate their appropriate length. However, TZAP expression has not been investigated in hepatocellular carcinomas (HCC). Materials and Methods: The clinical significance of TZAP expression in 72 HCC was investigated. Additionally, its findings were supported by open big data and cancer cell lines. Results: TZAP expression level was not associated with the clinical parameters of HCC. TZAP expression induced a poorer survival result (overall survival, p = 0.020; disease-free survival, p = 0.012). TCGA data showed TZAP expression was more frequently found in HCCs with hepatitis C infection (p = 0.023). However, TCGA data revealed that TZAP expression did not predict HCC prognosis. In a cell line study, TZAP inhibition via siRNA suppressed PLC/PRF/5 cell growth; however, cell viability was increased in HepG2 cells. Conclusions: We presented the clinical and prognostic values of TZAP expression in HCC tissues and cancer cell lines. Additionally, the TCGA results also revealed a significant role for TZAP expression. TZAP expression may involve HCC progression and its prognosis.

Loss of phospholipase Cγ1 suppresses hepatocellular carcinogenesis through blockade of STAT3-mediated cancer development.

Phospholipase C gamma 1 (PLCγ1) plays an oncogenic role in several cancers, alongside its usual physiological roles. Despite studies aimed at identifying the effect of PLCγ1 on tumors, the pathogenic role of PLCγ1 in the tumorigenesis and development of hepatocellular carcinoma (HCC) remains unknown. To investigate the function of PLCγ1 in HCC, we generated hepatocyte-specific PLCγ1 conditional knockout (PLCγ1f/f ; Alb-Cre) mice and induced HCC with diethylnitrosamine (DEN). Here, we identified that hepatocyte-specific PLCγ1 deletion effectively prevented DEN-induced HCC in mice. PLCγ1f/f ; Alb-Cre mice showed reduced tumor burden and tumor progression, as well as a decreased incidence of HCC and less marked proliferative and inflammatory responses. We also showed that oncogenic phenotypes such as repressed apoptosis, and promoted proliferation, cell cycle progression and migration, were induced by PLCγ1. In terms of molecular mechanism, PLCγ1 regulated the activation of signal transducer and activator of transcription 3 (STAT3) signaling. Moreover, PLCγ1 expression is elevated in human HCC and correlates with a poor prognosis in patients with HCC. Our results suggest that PLCγ1 promotes the pathogenic progression of HCC, and PLCγ1/STAT3 axis was identified as a potential therapeutic target pathway for HCC.

RPL17 Promotes Colorectal Cancer Proliferation and Stemness through ERK and NEK2/ß-catenin Signaling Pathways.

Aims: Ribosomal protein L17 (RPL17), a 60S subunit component, is up-regulated in colorectal cancer (CRC). However, its oncogenic role in CRC progression remains unexplored. Thus, we aimed to investigate the effect of RPL17 targeting on CRC in vitro and in vivo and whether RPL17 gained an extra-ribosomal function during CRC development. Methods: RPL17-specific siRNAs complexed with cationic lipids were transfected to CRC cells to silence target gene expression and then real-time RT-PCR and western blotting were applied to observe the change of expression or activity of genes or proteins of interest. Cell proliferation assay, clonogenic assay and cell cycle analysis were used to determine the in vitro effects of RPL17siRNAs on CRC cell growth, and a subcutaneous xenograft assay was applied to test the effect of RPL17siRNAs on in vivo tumor growth. RNA sequencing and western blotting were used to investigate the underlying mechanisms. Sphere-forming assay, invasion assay and migration assay were used to evaluate the effects of RPL17siRNAs on CRC stemness. Results: siRNA-mediated inhibition of RPL17 expression suppressed CRC cell growth and long-term colony formation by inducing apoptotic cell death. Similarly, targeting RPL17 effectively suppressed tumor formation in a mouse xenograft model. RNA sequencing of RPL17-silenced CRC cells revealed the same directional regulation of 159 (93 down- and 66 up-regulated) genes. Notably, NIMA-related kinase 2 (NEK2), which functionally cooperates with extracellular-regulated protein kinase (ERK) and plays a pivotal role in mitotic progression and stemness maintenance, was down-regulated. RPL17 silencing reduced NEK2, ß-catenin, and p-ERK protein levels. These molecular alterations reflected the reduction in sphere-forming capacity, expression of stem cell marker genes, migration, and invasion. Reversely, RPL17 overexpression increased the ability of long-term colony formation, migration, and invasion. Conclusion: Our findings indicate that RPL17 promotes CRC proliferation and stemness via the ERK and NEK2/ß-catenin signaling axis, and targeting RPL17 could be the next molecular strategy for both primary CRC treatment and prevention of secondary tumor formation.

Towards compact and snapshot channeled Mueller matrix imaging.

A polarization transformation can be fully described by a 4 × 4 matrix, known as the Mueller matrix. To fully image an object's polarization response, one needs to compute the Mueller matrix at each pixel of the image. Standard divison-of-time Mueller matrix imaging, because of its sequential nature, is ill-suited to applications requiring immediate and real-time imaging and is also bulky owing to multiple moving parts. In this work, we propose a new method for compact, snapshot Mueller matrix imaging, based on structured polarization illumination, and division-of-focal plane imaging, which can, in a single-shot, fully capture the Mueller matrix information of a band-limited signal.

Compensator design for polarization state management in waveguide displays based on polarization volume gratings.

In this work, we focus on the polarization state management in optical devices using optical elements based on circular polarization. As an example, we point out the issue in a waveguide display using circular polarization optical elements as input/output couplers, where the polarization state of the light can change as it propagates in the waveguide due to total internal reflection (TIR). This has a negative effect on the waveguide output coupler efficiency, image uniformity, and the polarization multiplexing capability. To address this problem, we discussed two different methods to compensate the polarization state change. With the compensator applied to correct the polarization state change in the waveguide, the optical elements based on circular polarization can be used with their advantages as input/output couplers for waveguide displays.

Silencing CDCA8 Suppresses Hepatocellular Carcinoma Growth and Stemness via Restoration of ATF3 Tumor Suppressor and Inactivation of AKT/ß-Catenin Signaling.

Big data analysis has revealed the upregulation of cell division cycle associated 8 (CDCA8) in human hepatocellular carcinoma (HCC) and its poorer survival outcome. However, the functions of CDCA8 during HCC development remain unknown. Here, we demonstrate in vitro that CDCA8 silencing inhibits HCC cell growth and long-term colony formation and migration through the accumulation of the G2/M phase cell population. Conversely, CDCA8 overexpression increases the ability to undergo long-term colony formation and migration. RNA sequencing and bioinformatic analysis revealed that CDCA8 knockdown led to the same directional regulation in 50 genes (25 down- and 25 upregulated). It was affirmed based on protein levels that CDCA8 silencing downregulates the levels of cyclin B1 and p-cdc2 and explains how it could induce G2/M arrest. The same condition increased the protein levels of tumor-suppressive ATF3 and GADD34 and inactivated AKT/ß-catenin signaling, which plays an important role in cell growth and stemness, reflecting a reduction in sphere-forming capacity. Importantly, it was demonstrated that the extent of CDCA8 expression is much greater in CD133+ cancer stem cells than in CD133- cancer cells, and that CDCA8 knockdown decreases levels of CD133, p-Akt and ß-catenin and increases levels of ATF3 and GADD34 in the CD133+ cancer stem cell (CSC) population. These molecular changes led to the inhibition of cell growth and sphere formation in the CD133+ cell population. Targeting CDCA8 also effectively suppressed tumor growth in a murine xenograft model, showing consistent molecular alterations in tumors injected with CDCA8siRNA. Taken together, these findings indicate that silencing CDCA8 suppresses HCC growth and stemness via restoring the ATF3 tumor suppressor and inactivating oncogenic AKT/ß-catenin signaling, and that targeting CDCA8 may be the next molecular strategy for both primary HCC treatment and the prevention of metastasis or recurrence.

Targeting CALM2 Inhibits Hepatocellular Carcinoma Growth and Metastasis by Suppressing E2F5-mediated Cell Cycle Progression.

BACKGROUND/AIM: The aim of this study was to reveal the novel roles of calmodulin 2 (CALM2) in hepatocellular carcinoma (HCC) progression. MATERIALS AND METHODS: The effects of knockdown of CALM2 expression by siRNA were investigated using various experimental approaches in both cellular and molecular levels. RESULTS: Silencing of CALM2 inhibited HCC cell proliferation and colony formation through induction of apoptosis. At the molecular level, CALM2-specific knockdown led to the common dysregulation of 154 genes in HCC cells. Notably, E2F transcription factor 5 (E2F5), which is functionally associated with migration, invasion and proliferation, was generally down-regulated. These functional associations were confirmed in HCC clinical samples. Reflecting the molecular changes, CALM2 knockdown reduced the migration and invasion abilities of HCC cells and abrogated the potency of tumor formation in vivo. CONCLUSION: Targeting CALM2 may be a molecular strategy for both primary HCC treatment and prevention of metastasis or recurrence.

Clinicopathological Characteristics of TZAP Expression in Colorectal Cancers.

PURPOSE: The zinc finger protein, ZBTB48, is a telomere-associated protein. It was renamed as telomeric zinc finger-associated protein (TZAP) binding to elongated telomeres. However, its expression level was not measured in cancers. PATIENTS AND METHODS: We analyzed TZAP mRNA levels in 60 colorectal cancers (CRC) and its correlation with telomere length and TERT was studied. RESULTS: TZAP mRNA in CRC was higher statistically than that in paired non-cancerous tissues (p = 0.033). Higher TZAP was found in carcinoembryonic antigen (CEA)-positive CRCs (>5 ng/mL) (p = 0.012). Shorter telomere was found in CRCs with high TZAP expression than that with low TZAP expression (p = 0.010). According to quantitative correlation analysis, TZAP has a correlation with age (r = -0.349, p = 0.007), TERT (r = 0.279, p = 0.041) and telomere length (r = -0.305, p = 0.021). TZAP expression did not harbor prognostic value in CRC. Inhibition of TZAP expression by siRNA suppresses cell growth in HT29 cells; however, it resulted in increased cell viability in HCT116 cells. TZAP inhibition induces a decrease in mRNA levels of TERT in both HT29 and HCT116 cells. TCGA data analysis showed higher expression of TZAP showed poorer overall survival in colon cancer (p = 0.001); however, it did not have a significance in rectal cancer (p = 0.951). CONCLUSION: We suggested that TZAP may be a possible biomarker for CRC.

Histone deacetylase inhibitor CG200745 ameliorates high-fat diet-induced hypertension via inhibition of angiotensin II production.

Obesity is growing rapidly worldwide due to consumption of westernized diet and lack of exercise. Obesity is one of the major risk factors of hypertension. The novel histone deacetylase (HDAC) inhibitor CG200745 was originally developed to treat various cancers. Previous studies showed that CG200745 attenuated hypertension through inhibition of cardiac hypertrophy and fibrosis in deoxycorticosterone acetate-induced hypertensive rat. The purpose of this study is to investigate the role and underlying mechanism of CG200745 in high-fat diet (HFD)-induced hypertension. Nine-week old C57BL/6 mice were fed a normal diet (ND) or HFD for 17 weeks. Each group of mice was treated with vehicle or CG200745 by intraperitoneal injection for 9 days. HFD group showed higher body weight, blood pressure (BP), HDAC activities, angiotensinogen and renin expressions in kidney, angiotensin-converting enzyme (ACE) expression in the lung, serum angiotensin II (Ang II) concentration, and myosin light chain20 (MLC20) phosphorylation in mesenteric artery compared with ND group. CG200745 lowered BP, HDAC activity, renin and angiotensinogen in the kidney, ACE in the lung, serum Ang II level, and phosphorylation of MLC20 in HFD group. In conclusion, CG200745 ameliorated HFD-induced hypertension through inhibition of HDAC/Ang II/vascular contraction axis. Our results offer CG200745 as a novel therapeutic option for HFD-induced hypertension.

Improving near-eye display resolution by polarization multiplexing.

We present here an optical approach to boost the apparent pixel density by utilizing the superimposition of two shifted-pixel grids generated by a Pancharatnam-Berry deflector (PBD). The content of the two shifted pixel grids are presented to the observer's eye simultaneously using a polarization-multiplexing method. Considering the compact and lightweight nature of PBD, this approach has potential applications in near-eye display systems. Moreover, the same concept can be extended to projection displays with proper modifications.

Disruption of the Myc-PDE4B regulatory circuitry impairs B-cell lymphoma survival.

A large body of evidence suggests that B-cell lymphomas with enhanced Myc expression are associated with an aggressive phenotype and poor prognosis, which makes Myc a compelling therapeutic target. Phosphodiesterase 4B (PDE4B), a main hydrolyzer of cyclic AMP (cAMP) in B cells, was shown to be involved in cell survival and drug resistance in diffuse large B cell lymphomas (DLBCL). However, the interrelationship between Myc and PDE4B remains unclear. Here, we first demonstrate the presence of the Myc-PDE4B feed-forward loop, in which Myc and PDE4B mutually reinforce the expression of each other. Next, the combined targeting of Myc and PDE4 synergistically prevented the proliferation and survival of B lymphoma cells in vitro and in a mouse xenograft model. We finally recapitulated this combinatorial effect in Eµ-myc transgenic mice; co-inhibition of Myc and PDE4 suppressed lymphomagenesis and restored B cell development to the wild type level that was associated with marked reduction in Myc levels, unveiling the critical role of the Myc-PDE4B amplification loop in the regulation of Myc expression and the pathogenesis of B cell lymphoma. These findings suggest that the disruption of the Myc-PDE4B circuitry can be exploited in the treatment of B cell malignancies.

Photo-responsive dye-doped liquid crystals for smart windows.

An electric field drives most dye-doped liquid crystal devices. Here, we demonstrate a new photo-responsive dye-doped self-organized cholesteric liquid crystal device. Upon UV or blue light exposure, the helical twisting power of the chiral azobenzene changes because of the trans-cis isomerization. As a result, the initially vertically aligned liquid crystal directors and dye molecules will change from transparent state to dark state. Such a polarizer-free photo-activated dimmer can be used for wide range of applications, such as diffractive photonic devices, portable information system, vehicular head-up displays, and as a smart window for energy-saving buildings.

Stretchable, flexible, rollable, and adherable polarization volume grating film.

Volume Bragg gratings (VBGs) have many applications, including filters, wavelength multiplexing devices, and see-through displays. As a kind of VBGs, polarization volume gratings (PVGs) based on liquid crystal polymer have the advantages of nearly 100% efficiency, large deflection angle, and high polarization selectivity. However, previous reports regarding PVGs did not address high efficiency, tunable periodicity, and flexibility. Here, we report a stretchable, flexible, and rollable PVG film with high diffraction efficiency. The control of PVG by mechanical stretching is investigated, while the Bragg reflection band shift is evaluated quantitatively. Moreover, we quantified the deflection angle change's behavior, which has promising potential for laser beam steering applications. The mechanical robustness under stretch-release cycles is also scrutinized.

Fabrication of Pancharatnam-Berry phase optical elements with highly stable polarization holography.

Polarization-dependent diffraction based on Pancharatnam-Berry phase optical elements (PBOEs) offers considerable benefits compared to conventional metasurfaces, such as negligible absorption, nearly 100% diffraction efficiency and an inexpensive fabrication process. Polarization holography is a simple way to fabricate PBOEs, which entails the interference of beams with different polarizations to generate a spatial-varying polarization field. Thus, the quality of recorded PBOEs manifests high sensitivity to the length change and phase shift between polarized beams, usually caused by environmental vibration and air flow. Here, new polarization holography based on modified Sagnac interferometry is developed for fabricating liquid crystal-based PB gratings and lenses, where the pitch of grating and optical power of lens could be easily tuned. This approach offers high tolerance to environmental disturbance during the exposure process. Detailed design parameters are analyzed, and the fabricated PBOEs with high optical quality are also demonstrated.

Foveated imaging for near-eye displays.

The angular resolution of current near-eye display devices is still far below human-eye acuity. How to achieve retina-level resolution while keeping wide field-of-view (FOV) remains a great challenge. In this work, we demonstrate a multi-resolution foveated display with two display panels and an optical combiner. The first display panel provides a wide FOV but relatively low resolution for the surrounding region, while the second one offers an ultra-high resolution for the central fovea region, by an optical minifying system which enhances the effective resolution by 5 ×. In addition, a switchable Pancharatnam-Berry phase deflector is employed to shift the high-resolution region. The proposed design effectively reduces the pixelation and screen-door effect in near-eye displays.