Repulsive Sema3E-Plexin-D1 signaling coordinates both axonal extension and steering via activating an autoregulatory factor, Mtss1

Axon guidance molecules are critical for neuronal pathfinding because they regulate directionality and growth pace during nervous system development. However, the molecular mechanisms coordinating proper axonal extension and turning are poorly understood. Here, metastasis suppressor 1 (Mtss1), a membrane protrusion protein, ensured axonal extension while sensitizing axons to the Semaphorin 3E (Sema3E)-Plexin-D1 repulsive cue. Sema3E-Plexin-D1 signaling enhanced Mtss1 expression in projecting striatonigral neurons. Mtss1 localized to the neurite axonal side and regulated neurite outgrowth in cultured neurons. Mtss1 also aided Plexin-D1 trafficking to the growth cone, where it signaled a repulsive cue to Sema3E. Mtss1 ablation reduced neurite extension and growth cone collapse in cultured neurons. Mtss1-knockout mice exhibited fewer striatonigral projections and irregular axonal routes, and these defects were recapitulated in Plxnd1- or Sema3e-knockout mice. These findings demonstrate that repulsive axon guidance activates an exquisite autoregulatory program coordinating both axonal extension and steering during neuronal pathfinding.

EGCG-induced selective death of cancer cells through autophagy-dependent regulation of the p62-mediated antioxidant survival pathway

The effects of EGCG on the selective death of cancer cells by modulating antioxidant pathways through autophagy were explored in various normal and cancer cells. EGCG positively regulated the p62-KEAP1-NRF2-HO-1 pathway in normal cells, while negatively regulating it in cancer cells, leading to selective apoptotic death of cancer cells. In EGCG-treated MRC5 cells (EGCG-MRC5), autophagic flux was blocked, which was accompanied by the formation of p62-positive aggregates. However, EGCG-treated HeLa cells (EGCG-HeLa) showed incomplete autophagic flux and no aggregate formation. The levels of P-ULK1 S556 and S758 increased in EGCG-MRC5 through AMPK-mTOR cooperative interaction. In contrast, EGCG treatment in HeLa cells led to AMPK-induced mTOR inactivation, resulting in abrogation of P-ULK1 S556 and S758 levels. AMPK knockout in EGCG-HeLa restored positive regulation of the p62-mediated pathway, which was accompanied by increased P-mTOR S2448 and P-ULK1 S758 levels. Knockdown of 67LR in EGCG-HeLa abolished AMPK activity but did not restore the p62-mediated pathway. Surprisingly, both AMPK knockout and 67LR knockdown in EGCG-HeLa markedly increased cell viability, despite differential regulation of the antioxidant enzyme HO-1. In conclusion, EGCG induces the selective death of cancer cells through the modulation of at least two autophagy-dependent and independent regulatory pathways: negative regulation involves the mTOR-ULK1 (S556 and S758)-p62-KEAP1-NRF2-HO-1 axis via AMPK activation, whereas positive regulation occurs through the 67LR-AMPK axis.

Low-Dose Ionizing Radiation-Crosslinking Immunoprecipitation (LDIR-CLIP) Identified Irradiation-Sensitive RNAs for RNA-Binding Protein HuR-Mediated Decay

Although ionizing radiation (IR) is widely used for therapeutic and research purposes, studies on low-dose ionizing radiation (LDIR) are limited compared with those on other IR approaches, such as high-dose gamma irradiation and ultraviolet irradiation. High-dose IR affects DNA damage response and nucleotide-protein crosslinking, among other processes; however, the molecular consequences of LDIR have been poorly investigated. Here, we developed a method to profile RNA species crosslinked to an RNA-binding protein, namely, human antigen R (HuR), using LDIR and high-throughput RNA sequencing. The RNA fragments isolated via LDIR-crosslinking and immunoprecipitation sequencing were crosslinked to HuR and protected from RNase-mediated digestion. Upon crosslinking HuR to target mRNAs such as PAX6, ZFP91, NR2F6, and CAND2, the transcripts degraded rapidly in human cell lines. Additionally, PAX6 and NR2F6 downregulation mediated the beneficial effects of LDIR on cell viability. Thus, our approach provides a method for investigating post-transcriptional gene regulation using LDIR.

Microtubule acetylation induced by oxidative stress regulates subcellular distribution of lysosomal vesicles for amyloid-beta secretion

Excessive production and accumulation of amyloid-beta (Aβ) in the brain are one of the hallmarks of Alzheimer's disease (AD). Although oxidative stress is known to trigger and promote the progression of AD, the molecular relationship between oxidative stress and Aβ production is not yet fully understood. In this study, we demonstrate that microtubule acetylation induced by oxidative stress plays a critical role in Aβ production and secretion by altering the subcellular distribution of Aβ precursor protein (APP)-containing lysosomal vesicles. Under oxidative stress, both H4-APPSwe/Ind and HEK293T-APPSwe/Ind cell lines showed increased microtubule acetylation and Aβ secretion. Knockdown (KD) of alpha-tubulin N-acetyltransferase 1 (ATAT1) by using a lentiviral shRNA not only inhibited the generation of intermediate APP fragments, such as β-CTF and AICD, but also suppressed Aβ secretion. Oxidative stress promoted the dispersion of LAMP1-positive vesicles to the periphery of the cell through microtubule acetylation, leading to the formation of neutralized lysosomal vesicles (NLVs), which was inhibited by ATAT1 KD. Treatment of the cells with the dynein ATPase inhibitor EHNA or downregulation of LIS1, a regulator of dynein-mediated intracellular transport, increased the peripheral localization of NLVs and promoted Aβ secretion, whereas KD of ADP ribosylation factor like GTPase 8B showed the opposite result. ATAT1 KD in the hippocampal region of the 5×FAD AD mouse model also showed significant reductions in Aβ plaque accumulation and memory loss. Taken together, these findings suggest that oxidative stress-induced microtubule acetylation promotes the peripheral localization of lysosomal vesicles to form NLVs, thereby enhancing Aβ secretion.

Multiple toll-like receptors (TLRs) display differential bacterial and ligand specificity in the earthworm, Eisenia andrei

Toll-like receptors (TLRs), an ancient and well-conserved group of pattern recognition receptors (PRRs), recognize conserved pathogen-associated molecular patterns. TLRs consist of three domains: the extracellular N-terminal domain, containing one or more leucine-rich repeats (LRRs), responsible for the recognizing and binding of antigens; the type-I transmembrane domain; and the intracellular domain known as the Toll/Interleukin-1 receptor (TIR) domain required for the downstream signaling pathway. We identified six new full-length complementary DNA (cDNA) sequences, Ean-TLR1/2/3/4/5/6. The deduced amino acid sequences indicate that Ean-TLRs consist of one signal peptide, one LRR N-terminal domain (Ean-TLR4/5), varying numbers of LRRs, one (Ean-TLR1/2/3/4/5) or two (Ean-TLR6) LRR C-terminal domains, one type-I transmembrane domain, and a TIR domain. In addition, a TIR domain alignment revealed that three conserved motifs, designated as Box 1, Box 2, and Box 3, contain essential amino acid residues for downstream signaling activity. Phylogenetic analysis of earthworm TLRs generated two separate evolutionary branches representing single (sccTLR) and multiple (mccTLR) cysteine cluster TLRs. Ean-TLR1/2/3/4 (sccTLR type) and Ean-TLR6 (mccTLR type) were clustered with corresponding types of previously reported earthworm TLRs as well as TLRs from Clitellata and Polychaete. As PRRs, earthworm TLRs should be capable of sensing a diverse range of pathogens. Except for Ean-TLR3, which was not responsive to any bacteria, earthworm TLR expression was significantly induced by Gram-positive but not Gram-negative bacteria. Moreover, it is likely that earthworms can differentiate between different species of Gram-positive bacteria via their TLR responses. The ligand specificity of earthworm TLRs suggests that their pathogenic ligand recognition is likely to be as specific and diverse as the mammalian TLR pathogen-sensing system.

Downregulation of AP1S1 causes the lysosomal degradation of EGFR in non-small cell lung cancer

Matrix stiffness has been shown to play a critical role in cancer progression by influencing various cellular processes, including epidermal growth factor (EGF) signaling. However, the underlying molecular mechanisms are not fully understood. Here, we investigated the role of adaptor-related protein complex 1 subunit sigma 1 (AP1S1), a component of adaptor protein complex-1, in the regulation of EGF receptor (EGFR) intracellular trafficking during cancer cell progression. We found that AP1S1 expression was upregulated under stiff matrix conditions, resulting in the regulation of EGFR trafficking in non-small cell lung adenocarcinoma cells. Knockout of AP1S1 caused the lysosomal degradation of EGFR, leading to suppressed EGF-induced anaplastic lymphoma receptor tyrosine kinase phosphorylation. In addition, the downregulation of AP1S1 increased the sensitivity of H1975 cancer cells, which are resistant to tyrosine kinase inhibitors, to erlotinib. Collectively, our results suggest that AP1S1 could regulate EGFR recycling under stiff matrix conditions, and AP1S1 inhibition could be a novel strategy for treating cancer cells resistant to EGFR-targeted anticancer drugs.

Beneficial Role of Multi-Disciplinary Treatment for Anaplastic Thyroid Cancer with Initial Distant Metastasis

PURPOSE/OBJECTIVE(S)

Anaplastic thyroid cancer (ATC) is a rare, highly aggressive tumor, with median survival around 5 months. Approximately half of the ATC patients presents with distant metastases at diagnosis, showing even more devastating prognosis, yet no outcome analysis had been reported. In this study, we aim to evaluate the clinical outcome of M1 ATC patients, and to define the group of patients who would benefit from local treatment based on multi-disciplinary approach.

MATERIALS/METHODS

A total of 133 histology-confirmed ATC patients underwent protocol-based multidisciplinary treatment including surgery and chemoradiotherapy (CRT) between May 2016 and January 2022. Patients received intensity-modulated radiotherapy of 30 fractions concurrently with paclitaxel on days 1, 8 and 15 every 4 weeks, and lenvatinib was added upon progression. After 18 fractions of CRT, interim response analysis using modified RECIST was conducted for adaptive treatment planning. We reviewed 58 patients with distant metastasis at diagnosis (stage IVC). Overall survival (OS) and progression-free survival (PFS) were measured from the day of diagnosis.

RESULTS

Most common metastatic site was lung (91.4%), followed by bone (31.0%) and brain (5.2%). Lenvatinib was added for 35 patients after any sign of progression. Fourteen patients received upfront surgery (16 debulking and 5 total) followed by adjuvant CRT in 16 patients. Thirty-one patients received upfront CRT with 2 patients receiving total resection after sufficient down-staging. Six (10%) patients could not complete radiotherapy but continued receiving systemic treatment. The median follow-up was 5.9 months. The median and 1-year OS were 6.2 months and 20.5%, and PFS were 3.7 months and 3.5%. Total RT dose over 60 Gy significantly improved median OS (7.5 vs 4.1 months, p = 0.012) and median PFS (4.4 vs 3.0, p = 0.010). Patients with less than 10 initial metastatic tumors showed better median OS (9.1 vs 4.6 months, p = 0.002) but not PFS (5.1 vs 3.6, p = 0.485). At interim analysis, early response (CR, PR and SD) of primary tumor was not associated with survival, while progression of distant metastases showed significantly worse median OS (9.8 vs 4.6 months, p = 0.001). More than 10 metastatic tumors (HR 2.73, 95% CI 1.32-5.66) and stable metastasis at interim analysis (HR 2.39, 95% CI 1.04-5.48) remained as significant factor in the multivariable cox regression analysis. Median OS and PFS of patients with less than 10 metastases showing no progression at interim analysis were 9.1 months, and 5.1 months.

CONCLUSION

Local treatment combined with chemotherapy for M1 ATC patients showed outcome comparable to those of non-metastatic ATC results. Active local treatment should be considered especially for patients with less than 10 metastases, and patients without distant progression in early response evaluation.

Optimal Planning Target Margin for Prostate Radiotherapy Based on Interfractional and Intrafractional Variability Assessment during 1.5T MR-Guided Radiotherapy

PURPOSE/OBJECTIVE(S)

MR-guided radiotherapy (MRgRT) provides superior soft-tissue contrast over CT-based image guidance. We collected and analyzed daily pre-treatment (PRE) and real-time motion-monitoring (MM) MR images of patients receiving prostate radiotherapy to assess interfractional and intrafractional variability of prostate using two localization methods: pelvic bony anatomy (bone) and prostate during online adaptive radiotherapy (ART).

MATERIALS/METHODS

PRE and MM MRIs for the first five fractions of twenty prostate cancer patients who received definitive MRgRT with 1.5T MRI were collected. Using MIM software, rigid registration between PRE MRI and planning CT images based on pelvic bony anatomy and prostate reproduced bone localization and online ART, respectively. To determine interfractional setup margin (SM), prostate was delineated on all PRE MRIs registered after bone and prostate localizations by a radiation oncologist, and centroid values of prostate contours between planning CT and PRE MRIs were compared. To determine interobserver variability, another radiation oncologist, a medical physicist, and a radiotherapist contoured prostate for both localization methods. For internal margin (IM) assessment, we used MM MRIs of the five patients who had all three sets of coronal, sagittal, and axial cine images and determined the maximum contour displacement using in-house MATLAB-based software converting binary image files to 2D cine images with a superimposed grid of 1 mm spacing.

RESULTS

A total of 100 PRE and 25 MM MRIs were analyzed. Four hundred prostate contours were delineated on MR images registered with planning CT based on both bony anatomy and prostate. After bone localization, SM was 0.57±0.42 mm in left-right (LR), 2.45±1.98 mm in anterior-posterior (AP), and 2.28±2.08 mm in superior-inferior (SI) directions, and IO was 1.06±0.58 mm in LR, 2.32±1.08 mm in AP, and 3.30±1.85 mm in SI directions. After prostate localization, SM was 0.76±0.57 mm in LR, 1.89±1.60 mm in AP, and 2.2±1.79 mm in SI directions, and IO was 1.11±0.55 mm in LR, 2.13±1.07 mm in AP, and 3.53±1.65 mm in SI directions. Average IM was 2.12±0.86 mm, 2.24±1.07 mm, and 2.84±0.88 mm in LR, AP, and SI directions, respectively.

CONCLUSION

Using daily MRIs from MRgRT, we showed that movements in the SI direction were the largest source of variability in prostate definitive RT. In addition, interobserver variability was a non-negligible source of margin. Optimal PTV margin should also consider internal margin, especially in the SI direction.

Disruption of type I interferon pathway and reduced production of IFN-α by parabens in virus-infected dendritic cells

BACKGROUND

Parabens are widely used preservatives commonly found in foods, cosmetics, and industrial products. Several studies have examined the effects of parabens on human health owing to widespread and continuous exposure to them in daily life. However, little is known about their immune-regulatory effects.

OBJECTIVE

Here, we aimed to investigate whether methylparaben, ethylparaben, and propylparaben affect the function of dendritic cells (DCs) as the most potent antigen-presenting cells that play a critical role in the initiation of adaptive immune responses.

METHODS

Bone-marrow derived DCs (BMDCs) were treated with three types of parabens (methylparaben, ethylparaben, and propylparaben) for 12 h. Subsequently, the transcriptomic profile was analyzed using RNA sequencing with further gene set enrichment analysis based on commonly regulated differentially expressed genes (DEGs). To test whether parabens suppress the production of type-I interferons (IFN-I) in BMDCs during viral infection, BMDCs or paraben-treated BMDCs were infected with Lymphocytic Choriomeningitis Virus (LCMV) at 10 multiplicity of infection (MOI) and measured the production of IFN-α1.

RESULTS

Transcriptomic analyses revealed that all three types of parabens reduced the transcription levels of genes in virus infection-associated pathways, such as IFN-I responses in BMDCs. Furthermore, parabens considerably reduced IFN-α1 production in the virus-infected BMDCs.

CONCLUSION

Our study is the first to show that parabens may modulate anti-viral immune responses by regulating DCs.

Polypropylene microplastics promote metastatic features in human breast cancer

Microplastics (MPs) are now a global issue due to increased plastic production and use. Recently, various studies have been performed in response to the human health risk assessment. However, these studies have focused on spherical MPs, which have smooth edges and a spherical shape and account for less than 1% of MPs in nature. Unfortunately, studies on fragment-type MPs are very limited and remain in the initial stages. In this study, we studied the effect that 16.4 µm fragment type polypropylene (PP) MPs, which have an irregular shape and sharp edges and form naturally in the environment, had on breast cancer. The detrimental effects of PPMPs on breast cancer metastasis were examined. Here, 1.6 mg/ml of PPMP, which does not induce cytotoxicity in MDA-MB-231, was used, and at this concentration, PPMP did not induce morphological changes or cellular migrating in the MDA-MB-231 and MCF-7 cells. However, PPMP incubation for 24 hours in the MDA-MB-231 cells significantly altered the level of cell cycle-related transcripts in an RNA-seq analysis. When confirmed by qRT-PCR, the gene expression of TMBIM6, AP2M1, and PTP4A2 was increased, while the transcript level of FTH1 was decreased. Further, secretion of the pro-inflammatory cytokine IL-6 from cancer cells was elevated with the incubation of PPMP for 12 hours. These results suggest that PPMP enhances metastasis-related gene expression and cytokines in breast cancer cells, exacerbating breast cancer metastasis.

Slit-Robo expression in the leech nervous system: insights into eyespot evolution

BACKGROUND

Slit and Robo are evolutionarily conserved ligand and receptor proteins, respectively, but the number of slit and robo gene paralogs varies across recent bilaterian genomes. Previous studies indicate that this ligand-receptor complex is involved in axon guidance. Given the lack of data regarding Slit/Robo in the Lophotrochozoa compared to Ecdysozoa and Deuterostomia, the present study aims to identify and characterize the expression of Slit/Robo orthologs in leech development.

RESULTS

We identified one slit (Hau-slit), and two robo genes (Hau-robo1 and Hau-robo2), and characterized their expression spatiotemporally during the development of the glossiphoniid leech Helobdella austinensis. Throughout segmentation and organogenesis, Hau-slit and Hau-robo1 are broadly expressed in complex and roughly complementary patterns in the ventral and dorsal midline, nerve ganglia, foregut, visceral mesoderm and/or endoderm of the crop, rectum and reproductive organs. Before yolk exhaustion, Hau-robo1 is also expressed where the pigmented eye spots will later develop, and Hau-slit is expressed in the area between these future eye spots. In contrast, Hau-robo2 expression is extremely limited, appearing first in the developing pigmented eye spots, and later in the three additional pairs of cryptic eye spots in head region that never develop pigment. Comparing the expression of robo orthologs between H. austinensis and another glossiphoniid leech, Alboglossiphonia lata allows to that robo1 and robo2 operate combinatorially to differentially specify pigmented and cryptic eyespots within the glossiphoniid leeches.

CONCLUSIONS

Our results support a conserved role in neurogenesis, midline formation and eye spot development for Slit/Robo in the Lophotrochozoa, and provide relevant data for evo-devo studies related to nervous system evolution.

c-Jun N-terminal kinase 1 (JNK1) phosphorylates OTX2 transcription factor that regulates early retinal development

BACKGROUND

The transcription factor orthodenticle homeobox 2 (OTX2) has critical functions in brain and eye development, and its mutations in humans are related to retinal diseases, such as ocular coloboma and microphthalmia. However, the regulatory mechanisms of OTX2 are poorly identified.

OBJECTIVE

The identification of JNK1 as an OTX2 regulatory protein through the protein interaction and phosphorylation.

METHODS

To identify the binding partner of OTX2, we performed co-immunoprecipitation and detected with a pooled antibody that targeted effective kinases. The protein interaction between JNK1 and OTX2 was identified with the co-immunoprecipitation and immunocytochemistry. In vivo and in vitro kinase assay of JNK1 was performed to detect the phosphorylation of OTX2 by JNK1.

RESULTS

JNK1 directly interacted with OTX2 through the transactivation domain at the c-terminal region. The protein-protein interaction and co-localization between JNK1 and OTX2 were further validated in the developing P0 mouse retina. In addition, we confirmed that the inactivation of JNK1 K55N mutant significantly reduced the JNK1-mediated phosphorylation of OTX2 by performing an immune complex protein kinase assay.

CONCLUSION

c-Jun N-terminal kinase 1 (JNK1) phosphorylates OTX2 transcription factor through the protein-protein interaction.

KPNA3 promotes epithelial-mesenchymal transition by regulating TGF-β and AKT signaling pathways in MDA-MB-231, a triple-negative breast cancer cell line

Karyopherin-α3 (KPNA3), a karyopherin- α isoform, is intimately associated with metastatic progression via epithelial-mesenchymal transition (EMT). However, the molecular mechanism underlying how KPNA3 acts as an EMT inducer remains to be elucidated. In this report, we identified that KPNA3 was significantly upregulated in cancer cells, particularly in triple-negative breast cancer, and its knockdown resulted in the suppression of cell proliferation and metastasis. The comprehensive transcriptome analysis from KPNA3 knockdown cells indicated that KPNA3 is involved in the regulation of numerous EMTrelated genes, including the downregulation of GATA3 and E-cadherin and the up-regulation of HAS2. Moreover, it was found that KPNA3 EMT-mediated metastasis can be achieved by TGF-β or AKT signaling pathways; this suggests that the novel independent signaling pathways KPNA3-TGF-β-GATA3-HAS2/E-cadherin and KPNA3-AKT-HAS2/E-cadherin are involved in the EMT-mediated progress of TNBC MDA-MB-231 cells. These findings provide new insights into the divergent EMT inducibility of KPNA3 according to cell and cancer type. [BMB Reports 2023; 56(2): 120-125].

Hyaluronic Acid Nanoparticles as a Topical Agent for Treating Psoriasis

Although conventional topical approaches for treating psoriasis have been offered as an alternative, there are still unmet medical needs such as low skin-penetrating efficacy and off-target adverse effects. A hyaluronic acid nanoparticle (HA-NP) formed by self-assembly of HA-hydrophobic moiety conjugates has been broadly studied as a nanocarrier for long-term and target-specific delivery of drugs, owing to their excellent physicochemical and biological characteristics. Here, we identify HA-NPs as topical therapeutics for treating psoriasis using in vivo skin penetration studies and psoriasis animal models. Transcutaneously administered HA-NPs were found to be accumulated and associated with pro-inflammatory macrophages in the inflamed dermis of a psoriasis mouse model. Importantly, HA-NP exerted potent therapeutic efficacy against psoriasis-like skin dermatitis in a size-dependent manner by suppressing innate immune responses and restoring skin barrier function without overt toxicity signs. The therapeutic efficacy of HA-NPs on psoriasis-like skin dermatitis was due to the outermost hydrophilic HA shell layer of HA-NPs, independent of the molecular weight of HA and hydrophobic moiety, and comparable with that of other conventional psoriasis therapeutics widely used in the clinical settings. Overall, HA-NPs have the potential as a topical nanomedicine for treating psoriasis effectively and safely.

The Kleisin Subunits of Cohesin are Involved in the Fate Determination of Embryonic Stem Cells

As a potential candidate to generate an everlasting cell source to treat various diseases, embryonic stem cells are regarded as a promising therapeutic tool in the regenerative medicine field. Cohesin, a multi-functional complex that controls various cellular activities, plays roles not only in organizing chromosome dynamics but also in controlling transcriptional activities related to self-renewal and differentiation of stem cells. Here, we report a novel role of the α-kleisin subunits of cohesin (RAD21 and REC8) in the maintenance of the balance between these two stem-cell processes. By knocking down REC8, RAD21, or the non-kleisin cohesin subunit SMC3 in mouse embryonic stem cells, we show that reduction in cohesin level impairs their self-renewal. Interestingly, the transcriptomic analysis revealed that knocking down each cohesin subunit enables the differentiation of embryonic stem cells into specific lineages. Specifically, embryonic stem cells in which cohesin subunit RAD21 were knocked down differentiated into cells expressing neural alongside germline lineage markers. Thus, we conclude that cohesin appears to control the fate determination of embryonic stem cells.

Peptidoglycan recognition proteins from the earthworm, Eisenia andrei: Differential inducibility and tissue-specific expression

Several pattern recognition receptors (PRRs) involved in innate immunity have been identified and characterized in earthworms. Peptidoglycan recognition proteins (PGRPs) are highly conserved PRRs that activate effector pathways such as prophenoloxidase cascade and Toll-like receptor pathway. In addition, PGRPs function as an enzyme, N-acetylmuramoyl-l-alanine amidase (NAMLAA), to directly hydrolyze peptidoglycan. We identified four full-length complementary DNA (cDNA) sequences, Ean-PGRP1/2/3/4, in Eisenia andrei, an earthworm. Sequence and phylogenetic analyses indicate that earthworm PGRP orthologs resemble short PGRP member proteins. The subcellular localizations of four Ean-PGRPs lacking the transmembrane domain are predicted to be extracellular or cytoplasmic. All Ean-PGRPs contain a highly conserved PGRP domain with a conserved Zn²⁺ binding site including a tyrosine residue essential for active amidase activity. Three highly conserved amino-acid residues (His, Trp, and Thr) necessary for amidase activity are also present, indicating that the Ean-PGRPs can be predicted to have amidase activity. Furthermore, we demonstrate that the Ean-PGRP genes are differentially induced by certain bacterial species, suggesting that the innate immune system of earthworms is likely to be somewhat specific rather than entirely non-specific. Tissue expression patterns indicate that Ean-PGRP mRNAs are primarily expressed in the immune-competent tissues and that their expression is tissue-specific according to Ean-PGRP types, particularly for Ean-PGRP1.

Efficacy of subsequent chemotherapy for patients with BRCA1/2-mutated recurrent epithelial ovarian cancer progressing on olaparib versus placebo maintenance: post-hoc analyses of the SOLO2/ENGOT Ov-21 trial

BACKGROUND

In the SOLO2 trial (ENGOT Ov-21; NCT01874353), maintenance olaparib in patients with platinum-sensitive relapsed ovarian cancer (PSROC) and BRCA mutation significantly improved progression-free survival (PFS) and prolonged overall survival (OS). Following disease progression on olaparib, efficacy of subsequent chemotherapy remains unknown.

PATIENTS AND METHODS

We conducted a post-hoc hypothesis-generating analysis of SOLO2 data to determine the efficacy of different chemotherapy regimens following RECIST disease progression in patients who received olaparib or placebo. We evaluated time to second progression (TTSP) calculated from the date of RECIST progression to the next progression/death.

RESULTS

The study population comprised 147 patients who received chemotherapy as their first subsequent treatment after RECIST progression. Of these, 69 (47%) and 78 (53%) were originally randomized to placebo and olaparib arms, respectively. In the placebo-treated cohort, 27/69 and 42/69 received non-platinum and platinum-based chemotherapy, respectively, compared with 24/78 and 54/78, respectively, in the olaparib-treated cohort. Among patients treated with chemotherapy (N = 147), TTSP was significantly longer in the placebo than in the olaparib arm: 12.1 versus 6.9 months [hazard ratio (HR) 2.17, 95% confidence interval (CI) 1.47-3.19]. Similar result was obtained on multivariable analysis adjusting for prognostic factors at RECIST progression (HR 2.13, 95% CI 1.41-3.22). Among patients treated with platinum-based chemotherapy (n = 96), TTSP was significantly longer in the placebo arm: 14.3 versus 7.0 months (HR 2.89, 95% CI 1.73-4.82). Conversely, among patients treated with non-platinum-based chemotherapy (n = 51), the TTSP was comparable in the placebo and olaparib arms: 8.3 versus 6.0 months (HR 1.58, 95% CI 0.86-2.90).

CONCLUSIONS

Following progression from maintenance olaparib in the recurrent setting, the efficacy of platinum-based subsequent chemotherapy seems to be reduced in BRCA1/2-mutated patients with PSROC compared to patients not previously receiving poly (ADP-ribose) polymerase inhibitors (PARPi). The optimal strategy for patients who relapse after PARPi is an area of ongoing research.

Anti-inflammatory effect of Ailanthus altissima (Mill.) Swingle leaves in lipopolysaccharide-stimulated astrocytes

ETHNOPHARMACOLOGICAL RELEVANCE

Activated astrocytes are involved in the progression of neurodegenerative diseases. Traditionally, Ailanthus altissima (Mill.) Swingle, widely distributed in East Asia, has been used as a medicine for the treatment of fever, gastric diseases, and inflammation. Although A. altissima has been reported to play an anti-inflammatory role in peripheral tissues or cells, its role in the central nervous system (CNS) remains unclear.

AIM OF THE STUDY

In the present study, we investigated the anti-inflammatory effects and mechanism of action of A. altissima in primary astrocytes stimulated by lipopolysaccharide (LPS).

MATERIALS AND METHODS

A nitrite assay was used to measure nitric oxide (NO) production, and the tetrazolium salt 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay was performed to determine cytotoxicity. The expression levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and mitogen-activated protein kinase (MAPK) were determined with western blotting. Reverse-transcription PCR was used to assess the expression of inflammatory cytokines. The levels of reactive oxygen species were measured using 2,7-dichlorodihydrofluorescein diacetate. Luciferase assay and immunocytochemistry were used for assessing nuclear factor-kappa B (NF-κB) transcription and p65 localization, respectively. Memory and social interaction were analyzed using the Y-maze and three-chamber tests, respectively.

RESULTS

The ethanol extract of A. altissima leaves (AAE) inhibited iNOS and COX-2 expression in LPS-stimulated astrocytes. Moreover, AAE reduced the transcription of various proinflammatory mediators, hindered NF-κB activation, and suppressed extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) activation without p38 activation. Ultra-high performance liquid chromatography with mass spectrometry analysis revealed that AAE comprised ethyl gallate, quercetin, and kaempferol, along with luteolin, which has anti-inflammatory properties, and repressed LPS-induced nitrite levels and the nuclear translocation of p65. Finally, oral administration of AAE attenuated LPS-induced memory and social impairment in mice and repressed LPS-induced ERK and JNK activation in the cortices of mice.

CONCLUSION

AAE could have therapeutic uses in the treatment of neuroinflammatory diseases via suppression of astrocyte activation.

An observational study of hydrodynamic impact on water mass transport due to tidal power generation

The world's largest Sihwa Tidal Power Plant (TPP), located on the west coast of Korea, was built in 2011 for the purpose of improving water quality and producing renewable energy. After several years of actual operation, most of the original purpose was achieved, but unexpected coastal environmental changes such as tidal flat damage and sediment accumulation also occurred. In this study, in order to understand the causes of these environmental changes, field observations were conducted near TPP, and spatial and temporal variability of flow structure and water exchange process were investigated. Three-dimensional velocity data were collected along the closed line surrounding the outside of the TPP for 11 h during spring tide and analyzed according to two discharge phases: power generation phase (PGP) and drainage phase (DP). The results show that the depth-averaged maximum current velocity was more than three times greater at DP than at PGP. Jet-like flow during DP caused very high horizontal shear, whereas vertical shear was relatively weak, indicating that the horizontal and vertical flow structures were very different. The most notable result is that the mass transport patterns between PGP and DP are significantly different, i.e., during PGP, mass transport is dominated on the left side of the TPP, whereas during DP, it occurs at the front of the TPP. This means that there is a strong spatiotemporal asymmetry between the inflow from the downstream (outside of the TPP) during PGP and the outflow from the upstream (inside of the TPP) during DP. These asymmetric processes can have a significant impact on the material exchange and sediment transport near the TPP. Since observational studies on TPP are extremely rare, this study is expected to contribute to future TPP related research, such as numerical modeling.

Multiomics analyses reveal early metabolic imbalance and mitochondrial stress in neonatal photoreceptors leading to cell death in Pde6brd1/rd1 mouse model of retinal degeneration

Retinal diseases exhibit extensive genetic heterogeneity and complex etiology with varying onset and severity. Mutations in over 200 genes can lead to photoreceptor dysfunction and/or cell death in retinal neurodegeneration. To deduce molecular pathways that initiate and/or drive cell death, we adopted a temporal multiomics approach and examined molecular and cellular events in newborn and developing photoreceptors before the onset of degeneration in a widely-used Pde6brd1/rd1 (rd1) mouse, a model of autosomal recessive retinitis pigmentosa caused by PDE6B mutations. Transcriptome profiling of neonatal and developing rods from the rd1 retina revealed early downregulation of genes associated with anabolic pathways and energy metabolism. Quantitative proteomics of rd1 retina showed early changes in calcium signaling and oxidative phosphorylation, with specific partial bypass of complex I electron transfer, which precede the onset of cell death. Concurrently, we detected alterations in central carbon metabolism, including dysregulation of components associated with glycolysis, pentose phosphate and purine biosynthesis. Ex vivo assays of oxygen consumption and transmission electron microscopy validated early and progressive mitochondrial stress and abnormalities in mitochondrial structure and function of rd1 rods. These data uncover mitochondrial overactivation and related metabolic alterations as determinants of early pathology and implicate aberrant calcium signaling as an initiator of higher mitochondrial stress. Our studies thus provide a mechanistic framework with mitochondrial damage and metabolic disruptions as early drivers of photoreceptor cell death in retinal degeneration.

Postoperative Pneumonia and Aspiration Pneumonia Following Elderly Hip Fractures

OBJECTIVES

The present study aimed to investigate the incidence of and risk factors for postoperative pneumonia and aspiration pneumonia after hip fracture surgery.

DESIGN

Retrospective cohort study from 2005 to 2021.

SETTING

Asan Medical Center in Seoul, Republic of Korea.

PARTICIPANTS

A total 1,208 patients aged ≥ 65 years who underwent hip fracture surgery.

MEASUREMENTS

Postoperative pneumonia was defined as cases with new infiltration on chest x-ray or chest computed tomography (CT) after surgery or confirmed by a pulmonologist's consultation and diagnosis. Aspiration pneumonia was defined as: 1) radiologic findings of hospital-acquired pneumonia on chest radiographs or CT, medical record of aspiration pneumonia confirmed by a pulmonologist's consultation, and history of vomiting or aspiration, or 2) gravity-dependent opacity on chest CT when the history of vomiting or aspiration is ambiguous. Patient demographics, past medical history, pre-injury Koval score, Charlson Comorbidity Index (CCI), blood test results, length of hospital stay, and in-hospital mortality were evaluated. A comparison analysis and binary logistic regression were performed to identify the incidence and risk factors for postoperative pneumonia and aspiration pneumonia.

RESULTS

Postoperative pneumonia was diagnosed in 47 patients (3.9%), including 20 with aspiration pneumonia (1.7%). In the multivariate analysis, postoperative delirium (odds ratio [OR], 3.42; P < 0.001), American Society of Anesthesiologists (ASA) scores ≥ 3 (OR, 2.11; P = 0.021), and CCI (OR, 1.21; P = 0.013) were significant risk factors for postoperative pneumonia. Male sex (OR, 3.01; P = 0.017), postoperative delirium (OR, 3.16; P = 0.014), and preoperative serum albumin levels < 3.5 g/dL (OR, 7.00; P = 0.010) were significant risk factors for aspiration pneumonia.

CONCLUSION

ASA classification ≥ 3, higher CCI, and postoperative delirium were the risk factors for postoperative pneumonia. Male sex, postoperative delirium, and lower preoperative serum albumin level were the risk factors for aspiration pneumonia. Thus, physicians should pay attention to patients with the risk factors.

Beta-Pix-dynamin 2 complex promotes colorectal cancer progression by facilitating membrane dynamics

PURPOSE

Spatiotemporal regulation of cell membrane dynamics is a major process that promotes cancer cell invasion by acting as a driving force for cell migration. Beta-Pix (βPix), a guanine nucleotide exchange factor for Rac1, has been reported to be involved in actin-mediated cellular processes, such as cell migration, by interacting with various proteins. As yet, however, the molecular mechanisms underlying βPix-mediated cancer cell invasion remain unclear.

METHODS

The clinical significance of βPix was analyzed in patients with colorectal cancer (CRC) using public clinical databases. Pull-down and immunoprecipitation assays were employed to identify novel binding partners for βPix. Additionally, various cell biological assays including immunocytochemistry and time-lapse video microscopy were performed to assess the effects of βPix on CRC progression. A βPix-SH3 antibody delivery system was used to determine the effects of the βPix-Dyn2 complex in CRC cells.

RESULTS

We found that the Src homology 3 (SH3) domain of βPix interacts with the proline-rich domain of Dynamin 2 (Dyn2), a large GTPase. The βPix-Dyn2 interaction promoted lamellipodia formation, along with plasma membrane localization of membrane-type 1 matrix metalloproteinase (MT1-MMP). Furthermore, we found that Src kinase-mediated phosphorylation of the tyrosine residue at position 442 of βPix enhanced βPix-Dyn2 complex formation. Disruption of the βPix-Dyn2 complex by βPix-SH3 antibodies targeting intracellular βPix inhibited CRC cell invasion.

CONCLUSIONS

Our data indicate that spatiotemporal regulation of the Src-βPix-Dyn2 axis is crucial for CRC cell invasion by promoting membrane dynamics and MT1-MMP recruitment into the leading edge. The development of inhibitors that disrupt the βPix-Dyn2 complex may be a useful therapeutic strategy for CRC.

Proneural genes define ground-state rules to regulate neurogenic patterning and cortical folding

Asymmetric neuronal expansion is thought to drive evolutionary transitions between lissencephalic and gyrencephalic cerebral cortices. We report that Neurog2 and Ascl1 proneural genes together sustain neurogenic continuity and lissencephaly in rodent cortices. Using transgenic reporter mice and human cerebral organoids, we found that Neurog2 and Ascl1 expression defines a continuum of four lineage-biased neural progenitor cell (NPC) pools. Double⁺ NPCs, at the hierarchical apex, are least lineage restricted due to Neurog2-Ascl1 cross-repression and display unique features of multipotency (more open chromatin, complex gene regulatory network, G₂ pausing). Strikingly, selectively eliminating double⁺ NPCs by crossing Neurog2-Ascl1 split-Cre mice with diphtheria toxin-dependent "deleter" strains locally disrupts Notch signaling, perturbs neurogenic symmetry, and triggers cortical folding. In support of our discovery that double⁺ NPCs are Notch-ligand-expressing "niche" cells that control neurogenic periodicity and cortical folding, NEUROG2, ASCL1, and HES1 transcript distribution is modular (adjacent high/low zones) in gyrencephalic macaque cortices, prefiguring future folds.

Effect of dipeptidyl peptidase IV inhibitors, thiazolidinedione, and sulfonylurea on osteoporosis in patients with type 2 diabetes: population-based cohort study

The population-based cohort study used the Korean National Health Insurance claims database to evaluate the effect of anti-diabetic drugs on osteoporosis. The use of DPP-IV inhibitors does not increase the risk of osteoporosis compared with the use of sulfonylureas in patients with type 2 diabetes mellitus, while a weak association was found between thiazolidinediones and increased risk of osteoporosis.

PURPOSE

The current study aimed to evaluate the effect of dipeptidyl peptidase IV inhibitors (DPP-IVi), thiazolidinedione (TZD), and sulfonylurea (SU) on osteoporosis in patients with type 2 diabetes.

METHODS

A population-based cohort study was conducted in the Republic of Korea using the Korean National Health Insurance claims database. Data from 2012 to 2017 for patients of 50-99 years of age who were prescribed DPP-IVi, TZD, or SU during 2013-2015 were extracted from the database. Based on pre-defined criteria, a total of 381,404 patients were analyzed after inverse probability of treatment weighting. The association between the study drugs and osteoporosis was estimated using Cox proportional hazards models. Data of 220,166 patients who were prescribed DPP-IVi, 18,630 who were prescribed TZD, and 142,608 patients who were prescribed SU were set.

RESULTS

In the multivariate-adjusted analysis, the hazard ratio (HR) of osteoporosis in the DPP-IVi group was not significantly different from that of the SU group (HR: 0.97; 95% confidence interval (CI) 0.94-1.00), whereas the HR of osteoporosis in the TZD group was higher (HR: 1.13; 95% CI 1.06-1.20). In the subgroup analysis, the HRs of osteoporosis were higher with pioglitazone (HR: 1.14; 95% CI 1.06-1.23) in the TZD group and with glibenclamides (HR: 1.39; 95% CI 1.09-1.77) in the SU group, whereas drugs with lower HR in the DPP-IVi group were saxagliptin (HR: 0.93; 95% CI 0.87-0.99) and sitagliptin (HR: 0.93; 95% CI 0.89-0.97).

CONCLUSION

DPP-IV inhibitors do not increase the risk of osteoporosis compared with sulfonylureas in patients with type 2 diabetes mellitus, while a weak association was found between thiazolidinediones and increased risk of osteoporosis.

Pilot study of fractional microneedling radiofrequency for hidradenitis suppurativa assessed by clinical response and histology

BACKGROUND

Hidradenitis suppurativa (HS) is a devastating chronic inflammatory skin disease with frequent recurrences. Various systemic treatments and procedures have been used but the efficacy of fractional microneedling radiofrequency (FMR) has not been reported.

AIM

To evaluate the clinical and histological efficacy of FMR in the treatment of HS lesions.

METHODS

An 8-week, prospective, split-body, unblinded study was conducted, which enrolled 10 adult patients with mild to moderate HS to receive 3 sessions of FMR treatment biweekly. HS severity was assessed using the number and type of lesions, HS Physician Global Assessment (HS-PGA) and the modified Sartorius score (mSS). Skin biopsies were performed on participants to assess change in inflammation before and after FMR.

RESULTS

Severity of HS was significantly reduced on the FMR-treated side of the body, but not on the control side. Inflammatory HS lesions were significantly reduced after 4 weeks, while HS-PGA and mSS were significantly decreased after 6 weeks. Immunohistochemistry staining showed decreased expression of inflammatory markers including neutrophil elastases, interleukin (IL)-8 and IL-17, tumour necrosis factor-α, transforming growth factor-β1 and matrix metalloproteinases.

CONCLUSION

FMR may be a viable treatment option for mild to moderate HS.

Population-based, three-dimensional analysis of age- and sex-related femur shaft geometry differences

This study deals with differences of femoral geometric focus on the bowing and width. Analysis using three-dimensional skeletonization showed increase of femoral bowing and femur width over life (more in women), and widening of the medullary canal only in women after 50 years old, not in men.

INTRODUCTION

The changes in femur geometry that occur with aging and lead to fragility or insufficiency fracture remain unclear. The role of the lower limb geometry, including the femur and femoral bowing, has become a point of discussion, especially in atypical femur fracture. This study aimed to analyze femur shaft geometry using three-dimensional skeletonization.

METHODS

We acquired computed tomography images of both femurs obtained. A total of 1400 age- and sex-stratified participants were enrolled and were divided into subgroups according to age (by decade) and sex. The computed tomography images were used to produce 3-dimensional samplings of anatomical elements of the human femur using reconstruction and parametrization from these datasets. The process of skeletonization was conducted to obtain compact representation of the femur. With the skeletonization, we were able to compare all parameters according to age and sex.

RESULTS

The femur length was 424.4 ± 28.6 mm and was longer in men (P < 0.001). The minimum diameter of the medullary canal was 8.9 ± 2.0 mm. The radius of curvature (ROC) was 906.9 ± 193.3 mm. Men had a larger femur length, femur outer diameter, and the narrowest medullary diameter (P < 0.001, respectively). Women had significantly smaller ROC (P < 0.001). ROC decreased by 19.4% in men and 23.6% in women between the ages of 20 to 89 years. Femur width increased over life by 11.4% in men and 24.5% in women. Between the ages of 50 and 89 years, the medullary canal appears to have increased by 32.7% in women.

CONCLUSION

This geometry analysis demonstrated that femoral bowing and femoral width increased related to aging, and that the medullary canal widened after the age of 50 years in women. This cross-sectional study revealed important age- and sex-related differences in femur shaft geometry that occur with aging.

MRI-Visible Perivascular Spaces in the Centrum Semiovale Are Associated with Brain Amyloid Deposition in Patients with Alzheimer Disease-Related Cognitive Impairment

BACKGROUND AND PURPOSE

The association of perivascular spaces in the centrum semiovale with amyloid accumulation among patients with Alzheimer disease-related cognitive impairment is unknown. We evaluated this association in patients with Alzheimer disease-related cognitive impairment and β-amyloid deposition, assessed with [¹⁸F] florbetaben PET/CT.

MATERIALS AND METHODS

MR imaging and [¹⁸F] florbetaben PET/CT images of 144 patients with Alzheimer disease-related cognitive impairment were retrospectively evaluated. MR imaging-visible perivascular spaces were rated on a 4-point visual scale: a score of ≥3 or <3 indicated a high or low degree of MR imaging-visible perivascular spaces, respectively. Amyloid deposition was evaluated using the brain β-amyloid plaque load scoring system.

RESULTS

Compared with patients negative for β-amyloid, those positive for it were older and more likely to have lower cognitive function, a diagnosis of Alzheimer disease, white matter hyperintensity, the Apolipoprotein E ε4 allele, and a high degree of MR imaging-visible perivascular spaces in the centrum semiovale. Multivariable analysis, adjusted for age and Apolipoprotein E status, revealed that a high degree of MR imaging-visible perivascular spaces in the centrum semiovale was independently associated with β-amyloid positivity (odds ratio, 2.307; 95% CI, 1.036-5.136; P = .041).

CONCLUSIONS

A high degree of MR imaging-visible perivascular spaces in the centrum semiovale independently predicted β-amyloid positivity in patients with Alzheimer disease-related cognitive impairment. Thus, MR imaging-visible perivascular spaces in the centrum semiovale are associated with amyloid pathology of the brain and could be an indirect imaging marker of amyloid burden in patients with Alzheimer disease-related cognitive impairment.

Acetylation of UHRF1 Regulates Hemi-methylated DNA Binding and Maintenance of Genome-wide DNA Methylation

UHRF1 is a key regulator in DNA methylation maintenance. It binds histone H3K9me2/3 and hemi-methylated DNA and recruits DNMT1 to DNA replication forks during S phase. However, the regulatory mechanism of hemi-methylated DNA binding activity of UHRF1 remains unknown. In this study, we reveal that acetylation of UHRF1 is regulated by PCAF and HDAC1. We show that UHRF1 acetylation at K490 attenuates its binding affinity to hemi-methylated DNA. We analyze genome-wide DNA methylation and gene-expression patterns using stable cell lines and discover that cells where the endogenous UHRF1 is replaced with an acetyl-mimetic (UHRF1 K490Q) mutant show deficiencies in inherited DNA methylation and show different gene-expression patterns in genes related to cell survival. These results reveal that precise regulation of UHRF1 acetylation is required to maintain DNA methylation during cell division and control cell survival.

Transcriptomic profiling of three-dimensional cholangiocyte spheroids long term exposed to repetitive Clonorchis sinensis excretory-secretory products

Background

Biliary tract infection with the carcinogenic human liver fluke, Clonorchis sinensis, provokes chronic inflammation, epithelial hyperplasia, periductal fibrosis, and even cholangiocarcinoma. Complications are proportional to the intensity and duration of the infection. In addition to mechanical irritation of the biliary epithelia from worms, their excretory-secretory products (ESPs) cause chemical irritation, which leads to inflammation, proliferation, and free radical generation.

Methods

A three-dimensional in vitro cholangiocyte spheroid culture model was established, followed by ESP treatment. This allowed us to examine the intrinsic pathological mechanisms of clonorchiasis via the imitation of prolonged and repetitive in vivo infection.

Results

Microarray and RNA-Seq analysis revealed that ESP-treated cholangiocyte H69 spheroids displayed global changes in gene expression compared to untreated spheroids. In ESP-treated H69 spheroids, 185 and 63 probes were found to be significantly upregulated and downregulated, respectively, corresponding to 209 genes (p < 0.01, fold change > 2). RNA-Seq was performed for the validation of the microarray results, and the gene expression patterns in both transcriptome platforms were well matched for 209 significant genes. Gene ontology analysis demonstrated that differentially expressed genes were mainly classified into immune system processes, the extracellular region, and the extracellular matrix. Among the upregulated genes, four genes (XAF1, TRIM22, CXCL10, and BST2) were selected for confirmation using quantitative RT-PCR, resulting in 100% similar expression patterns in microarray and RNA-Seq.

Conclusions

These findings broaden our understanding of the pathological pathways of liver fluke-associated hepatobiliary disorders and suggest a novel therapeutic strategy for this infectious cancer.

Graphic abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-021-04717-2.

Mercury Chloride but Not Lead Acetate Causes Apoptotic Cell Death in Human Lung Fibroblast MRC5 Cells via Regulation of Cell Cycle Progression

Heavy metals are important for various biological systems, but, in excess, they pose a serious risk to human health. Heavy metals are commonly used in consumer and industrial products. Despite the increasing evidence on the adverse effects of heavy metals, the detailed mechanisms underlying their action on lung cancer progression are still poorly understood. In the present study, we investigated whether heavy metals (mercury chloride and lead acetate) affect cell viability, cell cycle, and apoptotic cell death in human lung fibroblast MRC5 cells. The results showed that mercury chloride arrested the sub-G₁ and G₂/M phases by inducing cyclin B1 expression. In addition, the exposure to mercury chloride increased apoptosis through the activation of caspase-3. However, lead had no cytotoxic effects on human lung fibroblast MRC5 cells at low concentration. These findings demonstrated that mercury chloride affects the cytotoxicity of MRC5 cells by increasing cell cycle progression and apoptotic cell death.

Transcriptome Analysis Reveals HgCl2 Induces Apoptotic Cell Death in Human Lung Carcinoma H1299 Cells through Caspase-3-Independent Pathway

Mercury is one of the detrimental toxicants that can be found in the environment and exists naturally in different forms; inorganic and organic. Human exposure to inorganic mercury, such as mercury chloride, occurs through air pollution, absorption of food or water, and personal care products. This study aimed to investigate the effect of HgCl₂ on cell viability, cell cycle, apoptotic pathway, and alters of the transcriptome profiles in human non-small cell lung cancer cells, H1299. Our data show that HgCl₂ treatment causes inhibition of cell growth via cell cycle arrest at G₀/G₁- and S-phase. In addition, HgCl₂ induces apoptotic cell death through the caspase-3-independent pathway. Comprehensive transcriptome analysis using RNA-seq indicated that cellular nitrogen compound metabolic process, cellular metabolism, and translation for biological processes-related gene sets were significantly up- and downregulated by HgCl₂ treatment. Interestingly, comparative gene expression patterns by RNA-seq indicated that mitochondrial ribosomal proteins were markedly altered by low-dose of HgCl₂ treatment. Altogether, these data show that HgCl₂ induces apoptotic cell death through the dysfunction of mitochondria.

Liposomal irinotecan plus fluorouracil/leucovorin versus FOLFIRINOX as the second-line chemotherapy for patients with metastatic pancreatic cancer: a multicenter retrospective study of the Korean Cancer Study Group (KCSG)

Background

There is no clear consensus on the recommended second-line treatment for patients with metastatic pancreatic cancer who have disease progression following gemcitabine-based therapy. We retrospectively evaluated the clinical outcomes of liposomal irinotecan (nal-IRI) plus fluorouracil/leucovorin (FL) and FOLFIRINOX (fluorouracil, leucovorin, irinotecan, and oxaliplatin) in patients who had failed on the first-line gemcitabine-based therapy.

Patients and methods

From January 2015 to August 2019, 378 patients with MPC who had received nal-IRI/FL (n = 104) or FOLFIRINOX (n = 274) as second-line treatment across 11 institutions were included in this retrospective study.

Results

There were no significant differences in baseline characteristics between groups, except age and first-line regimens. With a median follow-up of 6 months, the median progression-free survival (PFS) was 3.7 months with nal-IRI/FL versus 4.6 months with FOLFIRINOX (P = 0.44). Median overall survival (OS) was 7.7 months with nal-IRI/FL versus 9.7 months with FOLFRINOX (P = 0.13). There was no significant difference in PFS and OS between the two regimens in the univariate and multivariate analyses. The subgroup analysis revealed that younger age (<70 years) was associated with better OS with FOLFIRINOX. In contrast, older age (≥70 years) was associated with better survival outcomes with nal-IRI/FL. Adverse events were manageable with both regimens; however, the incidence of grade 3 or higher neutropenia and peripheral neuropathy was higher in patients treated with FOLFIRINOX than with nal-IRI/FL.

Conclusions

Second-line nal-IRI/FL and FOLFIRINOX showed similar effectiveness outcomes after progression following first-line gemcitabine-based therapy. Age could be the determining factor for choosing the appropriate second-line therapy.

•

This multicenter retrospective study investigated nal-IRI/FL and FOLFIRINOX outcomes after gemcitabine-based therapy.

•

We found no significant differences in outcome between nal-IRI/FL and FOLFIRINOX treatment.

•

Both regimens were well tolerated; however, neutropenia and peripheral neuropathy were more frequent with FOLFIRINOX.

•

Age (cut-off, 70 years) showed differential efficacy between chemotherapy regimens.

Safety and efficacy of transarterial embolisation for treatment of dorsal pancreatic artery haemorrhage

AIM

To evaluate the safety and efficacy of transarterial embolisation (TAE) of dorsal pancreatic artery (DPA) haemorrhage.

MATERIALS AND METHODS

Nineteen consecutive patients (M:F = 16:3, mean age 59.6 years) who underwent TAE of DPA in three tertiary medical centres between January 2001 to January 2020 were reviewed retrospectively. Angiographic features and the technical and clinical outcomes of TAE were analysed.

RESULTS

The clinical presentations were a bloody drain from the Jackson-Pratt drainage tube (n=8), melaena (n=7), abdominal pain (n=4), and haematochezia (n=3). Angiographic findings included pseudoaneurysm (n=14), contrast media extravasation (n=4), or abrupt cut-off of the arterial branch (n=1). The NBCA (N-butyl-cyanoacrylate; n=4), microcoils (n=4), and a combination of these agents (n=7) were used as embolic agents. The most common origin of the DPA in the present study cohort was the splenic artery (n=7), followed by the coeliac trunk (n=4), common hepatic artery (n=4), and superior mesenteric artery (n=4). Technical and clinical success rates were 100% and 84.2% (16/19), respectively. Of the three clinically unsuccessful cases, two patients were revealed to have newly developed bleeding from another artery. The other patient expired 1 day after the TAE procedure due to a progression of hepatic failure. In one patient, an asymptomatic non-target embolisation occurred in the right posterior tibial artery as a procedure-related complication. No major complications were observed.

CONCLUSION

TAE is safe and effective for the management of bleeding from the DPA. It is important to be aware of the DPA as a potential bleeding source, including the relevant clinical characteristics.

Intramedullary pneumorrhachis following a cervical epidural steroid injection

Pneumorrhachis (PR) is a rare radiological condition characterized by the presence of intraspinal air. PR is commonly classified as spontaneous (nontraumatic), traumatic, or iatrogenic, and iatrogenic PR is the most common and often occurs secondary to invasive procedures such as epidural anesthesia, lumbar puncture, or spinal surgery. PR is usually asymptomatic, but it can produce symptoms associated with its underlying pathology. Here, we report a rare case of intramedullary cervical PR following a cervical epidural steroid injection (ESI) and include pertinent discussion.

FAM83H and Autosomal Dominant Hypocalcified Amelogenesis Imperfecta

Autosomal dominant hypocalcified amelogenesis imperfecta (ADHCAI; OMIM #130900) is a genetic disorder exhibiting severe hardness defects and reduced fracture toughness of dental enamel. While the condition is nonsyndromic, it can be associated with other craniofacial anomalies, such as malocclusions and delayed or failed tooth eruption. Truncation mutations in FAM83H (OMIM *611927) are hitherto the sole cause of ADHCAI. With human genetic studies, Fam83h knockout and mutation-knock-in mouse models indicated that FAM83H does not serve a critical physiologic function during enamel formation and suggested a neomorphic mutation mechanism causing ADHCAI. The function of FAM83H remains obscure. FAM83H has been shown to interact with various isoforms of casein kinase 1 (CK1) and keratins and to mediate organization of keratin cytoskeletons and desmosomes. By considering FAM83H a scaffold protein to anchor CK1s, further molecular characterization of the protein could gain insight into its functions. In this study, we characterized 9 kindreds with ADHCAI and identified 3 novel FAM83H truncation mutations: p.His437*, p.Gln459*, and p.Glu610*. Some affected individuals exhibited hypoplastic phenotypes, in addition to the characteristic hypocalcification enamel defects, which have never been well documented. Failed eruption of canines or second molars in affected persons was observed in 4 of the families. The p.Glu610* mutation was located in a gap area (amino acids 470 to 625) within the zone of previously reported pathogenic variants (amino acids 287 to 694). In vitro pull-down studies with overexpressed FAM83H proteins in HEK293 cells demonstrated an interaction between FAM83H and SEC16A, a protein component of the COP II complex at endoplasmic reticulum exit sites. The interaction was mediated by the middle part (amino acids 287 to 657) of mouse FAM83H protein. Results of this study significantly extended the phenotypic and genotypic spectrums of FAM83H-associated ADHCAI and suggested a role for FAM83H in endoplasmic reticulum-to-Golgi vesicle trafficking and protein secretion (dbGaP phs001491.v1.p1).

Associations of marijuana with markers of chronic lung disease in people living with HIV

OBJECTIVES

The relationship between marijuana use and markers of chronic lung disease in people living with HIV (PLWH) is poorly understood.

METHODS

We performed a cross-sectional analysis of the Examinations of HIV-Associated Lung Emphysema (EXHALE) study, including 162 HIV-positive patients and 138 participants without HIV. We modelled marijuana exposure as: (i) current daily or weekly marijuana smoking vs. monthly or less often; or (ii) cumulative marijuana smoking (joint-years). Linear and logistic regression estimated associations between marijuana exposure and markers of lung disease, adjusted for tobacco smoking and other factors.

RESULTS

In PLWH, current daily or weekly marijuana use was associated with a larger forced vital capacity (FVC), larger total lung capacity and increased odds of radiographic emphysema compared with marijuana non-smokers in adjusted models; these associations were not statistically significant in participants without HIV. Marijuana joint-years were associated with higher forced expiratory volume in 1 s and FVC in PLWH but not with emphysema.

CONCLUSIONS

In PLWH, marijuana smoking was associated with higher lung volumes and potentially with radiographic emphysema. No consistently negative associations were observed between marijuana and measures of chronic lung health.

Dynein-mediated nuclear translocation of yes-associated protein through microtubule acetylation controls fibroblast activation

Myofibroblasts are the major cell type that is responsible for increase in the mechanical stiffness in fibrotic tissues. It has well documented that the TGF-β/Smad axis is required for myofibroblast differentiation under the rigid substrate condition. However, the mechanism driving myofibroblast differentiation in soft substrates remains unknown. In this research, we demonstrated that interaction of yes-associated protein (YAP) and acetylated microtubule via dynein, a microtubule motor protein drives nuclear localization of YAP in the soft matrix, which in turn increased TGF-β1-induced transcriptional activity of Smad for myofibroblast differentiation. Pharmacological and genetical disruption of dynein impaired the nuclear translocation of YAP and decreased the TGF-β1-induced Smad activity even though phosphorylation and nuclear localization of Smad occurred normally in α-tubulin acetyltransferase 1 (α-TAT1) knockout cell. Moreover, microtubule acetylation prominently appeared in the fibroblast-like cells nearby the blood vessel in the fibrotic liver induced by CCl4 administration, which was conversely decreased by TGF-β receptor inhibitor. As a result, quantitative inhibition of microtubule acetylation may be suggested as a new target for overcoming fibrotic diseases.

Investigation of photodarkening in tandem-pumped Yb-doped fibers

Investigation of photodarkening (PD) in Yb-doped fibers tandem-pumped at 1018 nm is reported. For a homemade Yb-doped aluminosilicate double-clad fiber (YADF), the transmitted power of a 633 nm probe beam is reduced by 2.4% over 2 hours for the tandem pumping configuration at 1018 nm, which is significantly smaller than 33.3% for a laser diode (LD) pumping at 976 nm. A tandem-pumped Yb fiber amplifier also shows a much smaller decrease in the amplified output power over time than a LD-pumped Yb fiber amplifier. Based on fluorescence spectra of the YADF, we can not only associate PD of the YADF to intrinsic oxygen deficiency centers or Tm³⁺ impurities but also confirm the impact of the excited Yb³⁺ ion density on PD. The benefits of the tandem pumping in a high-power Yb fiber laser system will be discussed.

Targeting NLRP3 Inflammasome Reduces Age-Related Experimental Alveolar Bone Loss

The cause of chronic inflammatory periodontitis, which leads to the destruction of periodontal ligament and alveolar bone, is multifactorial. An increasing number of studies have shown the clinical significance of NLRP3-mediated low-grade inflammation in degenerative disorders, but its causal linkage to age-related periodontitis has not yet been elucidated. In this study, we investigated the involvement of the NLRP3 inflammasome and the therapeutic potential of NLRP3 inhibition in age-related alveolar bone loss by using in vivo and in vitro models. The poor quality of alveolar bones in aged mice was correlated with caspase-1 activation by macrophages and elevated levels of IL-1β, which are mainly regulated by the NLRP3 inflammasome, in periodontal ligament and serum, respectively. Aged mice lacking Nlrp3 showed better bone mass than age-matched wild-type mice via a way that affects bone resorption rather than bone formation. In line with this finding, treatment with MCC950, a potent inhibitor of the NLRP3 inflammasome, significantly suppressed alveolar bone loss with reduced caspase-1 activation in aged mice but not in young mice. In addition, our in vitro studies showed that the addition of IL-1β encourages RANKL-induced osteoclastogenesis from bone marrow-derived macrophages and that treatment with MCC950 significantly suppresses osteoclastic differentiation directly, irrelevant to the inhibition of IL-1β production. Our results suggest that the NLRP3 inflammasome is a critical mediator in age-related alveolar bone loss and that targeting the NLRP3 inflammasome could be a novel option for controlling periodontal degenerative changes with age.

Ethylparaben induces apoptotic cell death in human placenta BeWo cells via the Caspase-3 pathway

Parabens are generally used as preservatives in foods, pharmaceuticals, and various other commercial products. Among them, ethylparaben has weaker estrogenic characteristics than endogenous estrogen. However, growing evidence indicates that ethylparaben has an adverse effect on various human tissues. Here, we investigated whether ethylparaben induces cell death by affecting cell viability, cell proliferation, cell cycle, and apoptosis using the human placenta cell line BeWo. Ethylparaben significantly decreased cell viability in a dose-dependent manner. It caused cell cycle arrest at sub-G1 by reducing the expression of cyclin D1, whereas it decreased the cell proportion at the G0/G1 and S phases. Furthermore, we verified that ethylparaben induces apoptotic cell death by enhancing the activity of Caspase-3. Taken together, our results suggest that ethylparaben exerts cytotoxic effects in human placental BeWo cells via cell cycle arrest and apoptotic pathways.

Transcriptome dynamics of alternative splicing events revealed early phase of apoptosis induced by methylparaben in H1299 human lung carcinoma cells

Methylparaben is most frequently used as an antimicrobial preservative in pharmaceuticals and foods. Methylparaben has been subjected to toxicological studies owing to the increasing concern regarding its possible impact on the environment and human health. However, the cytotoxicity and underlying mechanisms of methylparaben exposure in human lung cells have not been explored. Here, we investigated the effect of methylparaben on cell cycle, apoptotic pathways, and changes in the transcriptome profiles in human lung cells. Our results demonstrate that treatment with methylparaben causes inhibition of cell growth. In addition, methylparaben induced S- and G2/M-phase arrest as a result of enhanced apoptosis. Transcriptome analysis using RNA-seq revealed that mRNA expression of ER stress- and protein misfolding-related gene sets was upregulated in methylparaben-treated group. RNA splicing- and maturation-related gene sets were significantly down-regulated by methylparaben treatment. Interestingly, RNA-seq analysis at the transcript level revealed that alternative splicing events, especially retained intron, were markedly changed by a low dose of methylparaben treatment. Altogether, these data show that methylparaben induces an early phase of apoptosis through cell cycle arrest and downregulation of mRNA maturation.

Interventional treatment of arterial injury during blind central venous catheterisation in the upper thorax: experience from two centres

AIM

To evaluate the safety and clinical efficacy of interventional treatment for arterial injury during blind, central venous catheterisation in the upper thorax at two tertiary medical centres.

MATERIALS AND METHODS

Eighteen consecutive patients (37-81 years; M:F=8:10) who underwent interventional treatment for the arterial injuries that occurred during central venous catheterisation without any imaging guidance between November 2007 and December 2018 were included. Clinical data, angiographic findings, detailed interventional procedures, and technical and clinical outcomes were analysed retrospectively.

RESULTS

Arterial injury sites were the subclavian artery/branches (n=12), axillary artery/branches (n=2), and common carotid artery (n=4). The target vein was not correlated with the corresponding artery/branches in eight patients (44.4%); internal jugular vein to subclavian artery branches. Angiographic findings were pseudoaneurysm (66.7%, 12/18), contrast medium extravasation (22.2%, 4/18), or both (11.1%, n=2). A stent graft was inserted for the main trunk injuries in nine patients, with (n=2) or without (n=7) prior arterial branch embolisation to prevent potential endoleak, while embolisation for the arterial branch injuries was performed in nine patients. Direct percutaneous access with thrombin injection to the pseudoaneurysm or residual arteriovenous fistula was utilised in two. The technical and clinical success rate was 94.4% (17/18) each. There were no procedure-related complications. In one patient without immediate clinical success, there was a persistent pseudoaneurysm after stent graft placement, which was treated with in-stent balloon dilation.

CONCLUSION

Interventional treatment serves as a safe and effective treatment modality for inadvertent arterial injury related to blind, central venous access catheterisation in the upper thorax.

Efficacy and safety findings from DREAM: a phase III study of DHP107 (oral paclitaxel) versus i.v. paclitaxel in patients with advanced gastric cancer after failure of first-line chemotherapy

Background

Paclitaxel is currently only available as an intravenous (i.v.) formulation. DHP107 is a novel oral formulation of lipid ingredients and paclitaxel. DHP107 demonstrated comparable efficacy, safety, and pharmacokinetics to i.v. paclitaxel as a second-line therapy in patients with advanced gastric cancer (AGC). DREAM is a multicenter, open-label, prospective, randomized phase III study of patients with histologically/cytologically confirmed, unresectable/recurrent AGC after first-line therapy failure.

Methods and materials

Patients were randomized 1 : 1 to DHP107 (200 mg/m2 orally twice daily days 1, 8, 15 every 4 weeks) or i.v. paclitaxel (175 mg/m2 day 1 every 3 weeks). Patients were stratified by Eastern Cooperative Oncology Group performance status, disease status, and prior treatment; response was assessed (Response Evaluation Criteria in Solid Tumors) every 6 weeks. Primary end point: non-inferiority of progression-free survival (PFS); secondary end points: overall response rate (ORR), overall survival (OS), and safety. For the efficacy analysis, sequential tests for non-inferiority were carried out, first with a non-inferiority margin of 1.48, then with a margin of 1.25.

Results

Baseline characteristics were balanced in the 236 randomized patients (n = 118 per arm). Median PFS (per-protocol) was 3.0 (95% CI 1.7-4.0) months for DHP107 and 2.6 (95% CI 1.8-2.8) months for paclitaxel (hazard ratio [HR] = 0.85; 95% CI 0.64-1.13). A sensitivity analysis on PFS using independent central review showed similar results (HR = 0.93; 95% CI 0.70-1.24). Median OS (full analysis set) was 9.7 (95% CI 7.1 - 11.5) months for DHP107 versus 8.9 (95% CI 7.1-12.2) months for paclitaxel (HR = 1.04; 95% CI 0.76-1.41). ORR was 17.8% for DHP107 (CR 4.2%; PR 13.6%) versus 25.4% for paclitaxel (CR 3.4%; PR 22.0%). Nausea, vomiting, diarrhea, and mucositis were more common with DHP107; peripheral neuropathy was more common with paclitaxel. There were only few Grade≥3 adverse events, most commonly neutropenia (42% versus 53%); febrile neutropenia was reported infrequently (5.9% versus 2.5%). No hypersensitivity reactions occurred with DHP107 (paclitaxel 2.5%).

Conclusions

DHP107 as a second-line treatment of AGC was non-inferior to paclitaxel for PFS; other efficacy and safety parameters were comparable. DHP107 is the first oral paclitaxel with proven efficacy/safety for the treatment of AGC.

ClinicalTrials.gov

NCT01839773.

P2523Hand grip strength as a predictor of exercise capacity in coronary heart disease

A recent study has shown that quadriceps strength can be used to predict the level of exercise capacity in patients with coronary heart disease (CHD). We investigated whether the relationship between muscular strength and exercise capacity is also observed with hand grip strength (HGS). We studied 443 participants (age, 61.8±11.2 y; 77.7% male) who underwent coronary intervention and participated in cardiac rehabilitation between 2015 and 2018. Participants were assessed for grip strength, measured using a Jamar dynamometer. Logistic regression was used to assess the relationship between various clinical measures (HGS, age, sex, etc) with the distance walked on a 6-minute walk test (6MWT) and maximal oxygen uptake (VO2max). HGS was significantly related to distance walked on the 6MWT (r=0.435, p<0.001). It was the only predictor of all exercise capacity categories, and one of the strongest predictors of each exercise capacity category. A HGS of 25.5% of body weight predicted an achievement of a 200 m walk on the 6MWT (positive predictive value = 0.95). However, HGS less than 35.5% of body weight predicted that 500m could not be done in 6 minutes (negative predictive value = 0.97). This trend was also observed in the subgroups in which VO2max was measured. This study demonstrates that HGS is associated with exercise capacity in CHD and can be used to predict the level of exercise capacity. These findings may contribute to setting the recommended level of daily activity as well as the level of cardiac rehabilitation in CHD.

Logistic regression models for different levels of exercise capacity Level of exercise capacity B±S.E p-value Odd ratio 95% CI Distance of 6MWT   200 m Grip strength 0.054±0.014 <0.001 1.056 1.027–1.086   300 m Grip strength 0.042±0.009 <0.001 1.042 1.024–1.062   400 m Grip strength 0.047±0.011 <0.001 1.048 1.026–1.070   500 m Grip strength 0.051±0.016 0.001 1.053 1.021–1.086 VO2max level   4 METs Grip strength 0.054±0.010 <0.001 1.056 1.036–1.076   6 METs Grip strength 0.059±0.011 <0.001 1.061 1.039–1.083   8 METs Grip strength 0.081±0.015 <0.001 1.085 1.053–1.117   10 METs Grip strength 0.113±0.049 0.019 1.12 1.019–3.232 Data are presented as mean ± standard deviation (SD). 6MWT, 6-minute walk test; STEMI, ST-Elevation Myocardial Infarction; SE, standard error; CI, confidence interval; VO2max, Maximal Oxygen uptake; METs, Metabolic equivalents.