Unraveling the role of the mitochondrial one-carbon pathway in undifferentiated thyroid cancer by multi-omics analyses

The role of the serine/glycine metabolic pathway (SGP) has recently been demonstrated in tumors; however, the pathological relevance of the SGP in thyroid cancer remains unexplored. Here, we perform metabolomic profiling of 17 tumor-normal pairs; bulk transcriptomics of 263 normal thyroid, 348 papillary, and 21 undifferentiated thyroid cancer samples; and single-cell transcriptomes from 15 cases, showing the impact of mitochondrial one-carbon metabolism in thyroid tumors. High expression of serine hydroxymethyltransferase-2 (SHMT2) and methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) is associated with low thyroid differentiation scores and poor clinical features. A subpopulation of tumor cells with high mitochondrial one-carbon pathway activity is observed in the single-cell dataset. SHMT2 inhibition significantly compromises mitochondrial respiration and decreases cell proliferation and tumor size in vitro and in vivo. Collectively, our results highlight the importance of the mitochondrial one-carbon pathway in undifferentiated thyroid cancer and suggest that SHMT2 is a potent therapeutic target.

Notch signaling regulates mineralization via microRNA modulation in dental pulp stem cells

OBJECTIVES

This study investigated the miRNA expression profile in Notch-activated human dental stem pulp stem cells (DPSCs) and validated the functions of miRNAs in modulating the odonto/osteogenic properties of DPSCs.

METHODS

DPSCs were treated with indirect immobilized Jagged1. The miRNA expression profile was examined using NanoString analysis. Bioinformatic analysis was performed, and miRNA expression was validated. Odonto/osteogenic differentiation was examined using alkaline phosphatase staining, Alizarin Red S staining, as well as odonto/osteogenic-related gene and protein expression.

RESULTS

Fourteen miRNAs were differentially expressed in Jagged1-treated DPSCs. Pathway analysis revealed that altered miRNAs were associated with TGF-β, Hippo, ErbB signalling pathways, FoxO and Ras signalling. Target prediction analysis demonstrated that 7604 genes were predicted to be targets for these altered miRNAs. Enrichment analysis revealed relationships to various DNA bindings. Among differentially expressed miRNA, miR-296-3p and miR-450b-5p were upregulated under Jagged1-treated conditions. Overexpression of miR-296-3p and miR-450b-5p enhanced mineralization and upregulation of odonto/osteogenic-related genes, whereas inhibition of these miRNAs revealed opposing results. The miR-296-3p and miR-450b-5p inhibitors attenuated the effects of Jagged1-induced mineralization in DPSCs.

CONCLUSIONS

Jagged-1 promotes mineralization in DPSCs that are partially regulated by miRNA. The novel understanding of these miRNAs could lead to innovative controlled mechanisms that can be applied to modulate biology-targeted dental materials.

Targeting class A GPCRs for hard tissue regeneration

G protein-coupled receptors (GPCRs) play important roles in various pathogeneses and physiological regulations. Owing to their functional diversity, GPCRs are considered one of the primary pharmaceutical targets. However, drugs targeting GPCRs have not been developed yet to regenerate hard tissues such as teeth and bones. Mesenchymal stromal cells (MSCs) have high proliferation and multi-lineage differentiation potential, which are essential for hard tissue regeneration. Here, we present a strategy for targeting class A GPCRs for hard tissue regeneration by promoting the differentiation of endogenous MSCs into osteogenic and odontogenic progenitor cells. Through in vitro screening targeted at class A GPCRs, we identified six target receptors (LPAR1, F2R, F2RL1, F2RL2, S1PR1, and ADORA2A) and candidate drugs with potent biomineralization effects. Through a combination of profiling whole transcriptome and accessible chromatin regions, we identified that p53 acts as a key transcriptional activator of genes that modulate the biomineralization process. Moreover, the therapeutic potential of class A GPCR-targeting drugs was demonstrated in tooth pulpotomy and calvarial defect models. The selected drugs revealed potent regenerative effects in both tooth and bone defects, represented by newly formed highly mineralized regions. Consequently, this study provides translational evidence for a new regenerative strategy for damaged hard tissue.

Occlusive membranes for guided regeneration of inflamed tissue defects

Guided bone regeneration aided by the application of occlusive membranes is a promising therapy for diverse inflammatory periodontal diseases. Symbiosis, homeostasis between the host microbiome and cells, occurs in the oral environment under normal, but not pathologic, conditions. Here, we develop a symbiotically integrating occlusive membrane by mimicking the tooth enamel growth or multiple nucleation biomineralization processes. We perform human saliva and in vivo canine experiments to confirm that the symbiotically integrating occlusive membrane induces a symbiotic healing environment. Moreover, we show that the membrane exhibits tractability and enzymatic stability, maintaining the healing space during the entire guided bone regeneration therapy period. We apply the symbiotically integrating occlusive membrane to treat inflammatory-challenged cases in vivo, namely, the open and closed healing of canine premolars with severe periodontitis. We find that the membrane promotes symbiosis, prevents negative inflammatory responses, and improves cellular integration. Finally, we show that guided bone regeneration therapy with the symbiotically integrating occlusive membrane achieves fast healing of gingival soft tissue and alveolar bone.

Crif1 deficiency in dopamine neurons triggers early-onset parkinsonism

Mitochondrial dysfunction has been implicated in Parkinson's Disease (PD) progression; however, the mitochondrial factors underlying the development of PD symptoms remain unclear. One candidate is CR6-interacting factor1 (CRIF1), which controls translation and membrane insertion of 13 mitochondrial proteins involved in oxidative phosphorylation. Here, we found that CRIF1 mRNA and protein expression were significantly reduced in postmortem brains of elderly PD patients compared to normal controls. To evaluate the effect of Crif1 deficiency, we produced mice lacking the Crif1 gene in dopaminergic neurons (DAT-CRIF1-KO mice). From 5 weeks of age, DAT-CRIF1-KO mice began to show decreased dopamine production with progressive neuronal degeneration in the nigral area. At ~10 weeks of age, they developed PD-like behavioral deficits, including gait abnormalities, rigidity, and resting tremor. L-DOPA, a medication used to treat PD, ameliorated these defects at an early stage, although it was ineffective in older mice. Taken together, the observation that CRIF1 expression is reduced in human PD brains and deletion of CRIF1 in dopaminergic neurons leads to early-onset PD with stepwise PD progression support the conclusion that CRIF1-mediated mitochondrial function is important for the survival of dopaminergic neurons.

Assessing Health and Economic Benefits of Omega-3 Fatty Acid Supplementation on Cardiovascular Disease in the Republic of Korea

BACKGROUND

Cardiovascular disease (CVD) is the primary cause of mortality worldwide and imposes a significant social burden on many countries.

METHODS

This study assessed the health and economic benefits of omega-3 associated with CVD. The meta-analysis estimated the risk ratio (RR) and absolute risk reduction (ARR), and the economic impact was calculated using direct and indirect costs related to CVD treatments in Korean adults.

RESULTS

A total of 33 studies were included in the meta-analysis on CVD outcomes, with 80,426 participants in the intervention group and 80,251 participants in the control group. The meta-analysis determined a significant reduction in omega-3 in CVD (RR = 0.92, 95% CI: 0.86~0.97) and ARR (1.48%). Additionally, the subgroup analysis indicated that higher doses and the long-term consumption of omega-3 could further enhance these effects. After applying ARR from meta-analysis to the target population of about 1,167,370 in 2021, the Republic of Korea, it was estimated that omega-3 consumption could result in an economic benefit of KRW 300 billion by subtracting the purchase expenses of omega-3 supplements from the total social cost savings.

CONCLUSION

Omega-3 supplements can help to reduce the risk of CVD and subsequent economic benefits in the Republic of Korea.

Effect of a multichannel oral irrigator on periodontal health and the oral microbiome

Oral biofilms or dental plaques are one of the major etiological factors for diverse oral diseases. We aimed to evaluate the effect of a multichannel oral irrigator (MCOI) on periodontal health in 29 participants randomly divided into two groups: the MCOI group and the control group. To evaluate the effect of the MCOI on periodontal health, the modified Quigley Hein Plaque Index (PI), Mühlemann-Son Sulcus Bleeding Index (SBI), bleeding on probing (BOP), and swelling were evaluated and compared before and after MCOI use for 3 days. Although PI and SBI showed statistically significant increases in the control group, the MCOI group showed no significant changes in either parameter. Moreover, the percentage of BOP was significantly lower in the MCOI group. Saliva samples were analyzed by 16s rRNA amplicon sequencing to investigate changes in the oral microbiome. Sequencing results showed that Porphyromonas spp. were significantly increased in the control group, whereas no significant change was detected in the MCOI group. Using the MCOI, enriched populations and functional pathways were detected in pioneer species comprising non-mutans streptococci. These findings provide evidence of the effectiveness of the MCOI in maintaining periodontal health and a healthy microbial ecology in the oral cavity.

ATG9B Is a Poor Prognostic Marker Associated With Immune Evasion in Colon Adenocarcinoma

BACKGROUND/AIM

Autophagy-related genes (ATGs) are involved in autophagy activation, which has a pleiotropic role in cancer development. However, the potential value of ATG expression levels in colon adenocarcinoma (COAD) is unclear. This study aimed to examine the modulation of ATG expression levels and their association with clinical and molecular aspects of COAD.

MATERIALS AND METHODS

We used the clinical and molecular phenotypes and RNA sequencing datasets of the cancer genome atlas (TCGA)-COAD project using TCGAbiolinks and cBioPortal. Comparisons of ATG expression levels between tumor and normal tissues were performed using DESeq2 within R. Gene expression and immune cell infiltration levels were analyzed by TIMER.

RESULTS

ATG9B had the highest expression levels among ATGs in COAD tissues compared to normal tissues and was related to advanced stage and poor prognosis in COAD. In addition, ATG9B expression was positively associated with the consensus molecular subtype 4 and chromosomal instability but negatively correlated with tumor mutation burden. Furthermore, high ATG9B expression levels were associated with low immune cell infiltration and decreased expression of natural killer cell activation genes.

CONCLUSION

ATG9B is a poor prognostic biomarker driving immune evasion of COAD through negative correlation with immune cell infiltration.

Abstract 6069: Genomic and transcriptomic characterization of medullary thyroid cancer

Medullary thyroid carcinoma (MTC) is a rare thyroid malignancy derived from the parafollicular C cells of thyroid gland. It features relatively aggressive biologic behavior among thyroid cancers, but its genomic landscape has not yet been fully explored. Here, we conducted multi-omics data (whole genome sequencing (WGS), and bulk (bulk RNA-seq) or single nucleus RNA sequencing (snRNA-seq)) on ​​MTC, and found genetic characteristics of MTC and a new gene signature predicting aggressiveness of tumors. WGS was performed for 35 pairs of tumor specimens and normal thyroid tissues from 30 patients. And bulk RNA-seq for 59 samples (20 normal thyroid tissues, 26 primary MTCs, 9 recurred lymph nodes, and 4 metastatic lymph nodes) and snRNA-seq for 3 primary MTCs, and 2 recurred/metastatic lymph nodes were also performed. In WGS results, we verified driver mutations, including RET, RAS, and BRAF. Four patients were classified as germline RET mutations based on familial history. Somatic RET M918T mutations were occurred in 8 patients, 9 patients were observed other RET mutations. Also, we observed other somatic mutations such as HRAS and BRAF. Seven patients occurred somatic HRAS mutations (Q61L, Q61R, G13R, A11 and G15), and somatic BRAF mutations (G469A, K601E) were observed in two patients. We found broad-level copy-number alterations in ~50% of patients, and we also found a patient who shows whole-genome duplication. The copy-number alteration was associated with aggressive phenotype in MTC. In addition, we found complex rearrangements such as microhomology-mediated break-induced replication in five patients. Interestingly, we found intra-tumoral heterogeneity of several genes related to C cell differentiation through snRNA-seq analysis by comparing clusters of tumor cells. Using the genes, we calculated the C cell differentiation score of the samples with bulk RNA-seq by GSVA algorithm. This score was related to poor clinical characteristics such as recurrence. In conclusion, multi-omics profiling of MTC reveals that copy number alterations and C cell differentiation status are the important biomarkers for cancer aggressiveness.

Citation Format: Seong Eun Lee, Seongyeol Park, Shinae Yi, Joonoh Lim, Na Rae Choi, JungHak Kwak, June-Young Koh, Boram Yi, Jaemo Koo, Jae Won Chang, Young Seok Ju, Bon Seok Koo, Jin Man Kim, Young Joo Park, Minho Shong, Eun Kyung Lee, Jae Kyung Won, Yea Eun Kang, Kyu Eun Lee. Genomic and transcriptomic characterization of medullary thyroid cancer. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6069.

Single Cell Analysis of Human Thyroid Reveals the Transcriptional Signatures of Aging

The thyroid gland plays a critical role in the maintenance of whole-body metabolism. However, aging frequently impairs homeostatic maintenance by thyroid hormones due to increased prevalence of subclinical hypothyroidism associated with mitochondrial dysfunction, inflammation, and fibrosis. To understand the specific aging-related changes of endocrine function in thyroid epithelial cells, we performed single-cell RNA sequencing (RNA-seq) of 54 726 cells derived from pathologically normal thyroid tissues from 7 patients who underwent thyroidectomy. Thyroid endocrine epithelial cells were clustered into 5 distinct subpopulations, and a subset of cells was found to be particularly vulnerable with aging, showing functional deterioration associated with the expression of metallothionein (MT) and major histocompatibility complex class II genes. We further validated that increased expression of MT family genes are highly correlated with thyroid gland aging in bulk RNAseq datasets. This study provides evidence that aging induces specific transcriptomic changes across multiple cell populations in the human thyroid gland.

Functional expression of oxytocin receptors in pulp-dentin complex

Dental pulp-derived stromal cells (DPSCs) are a crucial cell population for maintaining the tissue integrity of the pulp-dentin complex. The oxytocin receptor (OXTR), a member of the G protein-coupled receptor (GPCR) superfamily, plays versatile roles in diverse biological contexts. However, the role of OXTR in dental pulp has not yet been fully understood. Here, we demonstrate the biological functions and significance of OXTR in DPSCs through a multidisciplinary approach. Microarray data of 494 GPCR genes revealed high OXTR expression in human DPSCs (hDPSCs). Blocking OXTR activity increased the expression of osteogenic and odontogenic marker genes, promoting hDPSC differentiation. Additionally, we found that OXTR is involved in extracellular matrix (ECM) remodeling through the regulation of the gene expression related to ECM homeostasis. We further demonstrated that these genetic changes are mediated by trascriptional activity of Yes-associated protein (YAP). Based on the results, a preclinical experiment was performed using an animal model, demonstrating that the application of an OXTR inhibitor to damaged pulp induced significant hard tissue formation. These results provide new insight into the oxytocin-OXTR system in the regenerative process of pulp-dentin complex.

Adrenomedullin2 stimulates progression of thyroid cancer in mice and humans under nutrient excess conditions

Thyroid cancer is associated with genetic alterations, e.g. BRAF^V600E , which may cause carcinomatous changes in hormone-secreting epithelial cells. Epidemiological studies have shown that overnutrition is related to the development and progression of cancer. In this study, we attempted to identify the cell nonautonomous factor responsible for the progression of BRAF^V600E thyroid cancer under overnutrition conditions. We developed a mouse model for inducible thyrocyte-specific activation of BRAF^V600E , which showed features similar to those of human papillary thyroid cancer. LSL-Braf^V600E ;TgCreER^T2 showed thyroid tumour development in the entire thyroid, and the tumour showed more abnormal cellular features with mitochondrial abnormalities in mice fed a high-fat diet (HFD). Transcriptomics revealed that adrenomedullin2 (Adm2) was increased in LSL-Braf^V600E ;TgCreER^T2 mice fed HFD. ADM2 was upregulated on the addition of a mitochondrial complex I inhibitor or palmitic acid with integrated stress response (ISR) in cancer cells. ADM2 stimulated protein kinase A and extracellular signal-regulated kinase in vitro. The knockdown of ADM2 suppressed the proliferation and migration of thyroid cancer cells. We searched The Cancer Genome Atlas and Genotype-Tissue Expression databases and found that increased ADM2 expression was associated with ISR and poor overall survival. Consistently, upregulated ADM2 expression in tumour cells and circulating ADM2 molecules were associated with aggressive clinicopathological parameters, including body mass index, in thyroid cancer patients. Collectively, we identified that ADM2 is released from cancer cells under mitochondrial stress resulting from overnutrition and acts as a secretory factor determining the progressive properties of thyroid cancer. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Dosimetric comparison between VMAT plans using the fast-rotating O-ring linac with dual-layer stacked MLC and helical tomotherapy for nasopharyngeal carcinoma

BACKGROUND

To compare the dosimetric profiles of volumetric modulated arc therapy (VMAT) plans using the fast-rotating O-ring linac (the Halcyon system) based on a dual-layer stacked multi-leaf collimator and helical tomotherapy (HT) for nasopharyngeal cancer (NPCa).

METHODS

For 30 NPCa patients, three sets of RT plans were generated, under the same policy of contouring and dose constraints: HT plan; Halcyon VMAT plan with two arcs (HL_2arc); and Halcyon VMAT plan with four arcs (HL_4arc), respectively. The intended dose schedule was to deliver 67.2 Gy to the planning gross target volume (P-GTV) and 56.0 Gy to the planning clinical target volume (P-CTV) in 28 fractions using the simultaneously integrated boost concept. Target volumes and organ at risks dose metrics were evaluated for all plans. Normal tissue complication probabilities (NTCP) for esophagus, parotid glands, spinal cord, and brain stem were compared.

RESULTS

The HT plan achieved the best dose homogeneity index for both P_GTV and P_CTV, followed by the HL_4arc and L_2arc plans. No significant difference in the dose conformity index (CI) for P_GTV was observed between the HT plan (0.80) and either the HL_2arc plan (0.79) or the HL_4arc plan (0.83). The HL_4arc plan showed the best CI for P_CTV (0.88), followed by the HL_2arc plan (0.83) and the HT plan (0.80). The HL_4arc plan (median, interquartile rage (Q1, Q3): 25.36 (22.22, 26.89) Gy) showed the lowest D_mean in the parotid glands, followed by the HT (25.88 (23.87, 27.87) Gy) and HL_2arc plans (28.00 (23.24, 33.99) Gy). In the oral cavity (OC) dose comparison, the HT (22.03 (19.79, 24.85) Gy) plan showed the lowest D_mean compared to the HL_2arc (23.96 (20.84, 28.02) Gy) and HL_4arc (24.14 (20.17, 27.53) Gy) plans. Intermediate and low dose regions (40-65% of the prescribed dose) were well fit to the target volume in HL_4arc, compared to the HT and HL_2arc plans. All plans met the dose constraints for the other OARs with sufficient dose margins. The between-group differences in the median NTCP values for the parotid glands and OC were < 3.47% and < 1.7% points, respectively.

CONCLUSIONS

The dosimetric profiles of Halcyon VMAT plans were comparable to that of HT, and HL_4arc showed better dosimetric profiles than HL_2arc for NPCa.

Hepatic transcriptome profiling according to growth rate reveals acclimation in metabolic regulatory mechanisms to cyclic heat stress in broiler chickens

Climate change has numerous effects on poultry that result in welfare concerns and economic losses in agricultural industries. However, the mechanisms underlying the acclimation to heat stress in poultry have not been comprehensively defined. Therefore, identifying associated patterns of gene regulation and understanding the molecular mechanisms of acclimation to a warmer environment will provide insights into the acclimation system of broiler chickens. We profiled differentially expressed genes (DEGs) associated with differences in growth performance under heat stress conditions in the liver tissues of broilers based on RNA sequencing data. The DEGs were identified by comparison to the gene expression levels of broilers exhibiting average growth at 28 d of age (D28A) and D36A relative to those at D21A. In D36A, 507 and 312 DEGs were up- and downregulated, respectively, whereas 400 and 156 DEGs were up- and downregulated in D28A, respectively. Pathway enrichment analysis further revealed that “fatty acid degradation” and “heat shock protein expression” were upregulated in broilers exhibiting a higher growth and weight, whereas “cell cycle arrest” and “amino acid metabolism” were downregulated. Transcriptome profiling revealed that the acclimatized group supplied fat and energy from the liver to tissues through the breakdown of fatty acids. Furthermore, homeostasis was maintained via heat shock proteins and antioxidant enzymes. The characterized candidate genes and mechanisms associated with the response to heat stress might serve as a foundation for improving the ability of broilers to acclimatize under heat stress conditions.

Colchicine as a novel drug for the treatment of osteosarcoma through drug repositioning based on an FDA drug library

Background

Colchicine is a traditional medication that is currently approved to treat gout and familial Mediterranean fever (FMF). However, colchicine has a wide range of anti-inflammatory activities, and several studies have indicated that it may be useful in a variety of other conditions, such as rheumatic disease, cardiac disease, and cancer. Osteosarcoma, the most common type of bone sarcoma, is derived from primitive bone-forming mesenchymal cells. In this study, we investigated whether colchicine could be used to treat osteosarcoma through the regulation of cell cycle signaling.

Methods

Two human osteosarcoma cell lines, U2OS and Saos-2, were used. A clonogenic assay was used to determine the antiproliferative effects of colchicine on osteosarcoma cells. Reactive oxygen species (ROS) production and apoptosis were measured by flow cytometry. Migration and invasion assays were performed to investigate the inhibitory effects of colchicine. The signaling pathways related to colchicine treatment were verified by GO biological process (GOBP) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses.

Results

Colchicine was selected as the lead compound based on the results of initial screening and cell viability assays conducted in Saos-2 and U2Os cells. Colchicine reduced the viability of Saos-2 and U2OS cells in a concentration-dependent manner. It also significantly inhibited colony-forming ability and induced ROS production and apoptosis. It also inhibited the migration and invasion of both Saos-2 and U2OS cells. GOBP and KEGG enrichment analyses indicated the involvement of microtubule-based processes and cancer-related pathways.

Conclusions

These findings suggest that colchicine has therapeutic potential in osteosarcoma.

ANKRD13a controls early cell-death checkpoint by interacting with RIP1 independent of NF-κB

In TNF signaling, ubiquitination of RIP1 functions as an early cell-death checkpoint, which prevents the spatial transition of the signaling complex from complex-I to death-inducing complex-II. Here, we report that ankyrin repeat domain 13a (ANKRD13a) acts as a novel component of complex-II to set a higher signal threshold for the cytotoxic potential of TNF. ANKRD13a deficiency is sufficient to turn the response to TNF from survival to death by promoting the formation of complex-II without affecting NF-κB activation. ANKRD13a binds to ubiquitinated-RIP1 via its UIM, and subsequently limits the association of FADD and caspase-8 with RIP1. Moreover, high ANKRD13a expression is inversely correlated with apoptotic phenotypes in ovarian cancer tissues and is associated with poor prognosis. Our work identifies ANKRD13a as a novel gatekeeper of the early cell-death checkpoint, which may function as part of an escape mechanism from cell death in some cancers.

Transcriptomic analysis of papillary thyroid cancer focused on immune-subtyping, oncogenic fusion, and recurrence

Objectives

Thyroid cancer is the most common endocrine tumor, with rapidly increasing incidence worldwide. However, its transcriptomic characteristics associated with immunological signatures, driver fusions, and recurrence markers remain unclear. We aimed to investigate the transcriptomic characteristics of advanced papillary thyroid cancer.

Methods

This study included 282 papillary thyroid cancer tumor samples and 155 normal samples from Chungnam National University Hospital and Seoul National University Hospital. Transcriptomic quantification was determined by high-throughput RNA sequencing. We investigated the associations of clinical parameters and molecular signatures using RNA sequencing. We validated predictive biomarkers using the Cancer Genome Atlas database.

Results

Through a comparison of differentially expressed genes, gene sets, and pathways in papillary thyroid cancer compared to normal tumor-adjacent tissue, we found increased immune signaling associated with cytokines or T cells and decreased thyroid hormone synthetic pathways. In addition, patients with recurrence presented increased CD8+ T-cell and Th1-cell signatures. Interestingly, we found differentially overexpressed genes related to immune-escape signaling such as CTLA4, IDO1, LAG3, and PDCD1 in advanced papillary thyroid cancer with a low thyroid differentiation score. Fusion analysis showed that the PI3K and mitogen-activated protein kinase (MAPK) signaling pathways were regulated differently according to the RET fusion partner genes (CCDC6 or NCOA4). Finally, we identified HOXD9 as a novel molecular biomarker that predicts the recurrence of thyroid cancer in addition to known risk factors (tumor size, lymph node metastasis, and extrathyroidal extension).

Conclusion

We identified a high association with immune-escape signaling in the immune-hot group with aggressive clinical characteristics among Korean thyroid cancer patients. Moreover, RET fusion differentially regulated PI3K and MAPK signaling depending on the partner gene of RET, and HOXD9 was found to be a recurrence marker for advanced papillary thyroid cancer.

PINK1 deficiency impairs osteoblast differentiation through aberrant mitochondrial homeostasis

Background

PTEN-induced kinase 1 (PINK1) is a serine/threonine-protein kinase in mitochondria that is critical for mitochondrial quality control. PINK1 triggers mitophagy, a selective autophagy of mitochondria, and is involved in mitochondrial regeneration. Although increments of mitochondrial biogenesis and activity are known to be crucial during differentiation, data regarding the specific role of PINK1 in osteogenic maturation and bone remodeling are limited.

Methods

We adopted an ovariectomy model in female wildtype and Pink1^−/− mice. Ovariectomized mice were analyzed using micro-CT, H&E staining, Masson’s trichrome staining. RT-PCR, western blot, immunofluorescence, alkaline phosphatase, and alizarin red staining were performed to assess the expression of PINK1 and osteogenic markers in silencing of PINK1 MC3T3-E1 cells. Clinical relevance of PINK1 expression levels was determined via qRT-PCR analysis in normal and osteoporosis patients.

Results

A significant decrease in bone mass and collagen deposition was observed in the femurs of Pink1^−/− mice after ovariectomy. Ex vivo, differentiation of osteoblasts was inhibited upon Pink1 downregulation, accompanied by impaired mitochondrial homeostasis, increased mitochondrial reactive oxygen species production, and defects in mitochondrial calcium handling. Furthermore, PINK1 expression was reduced in bones from patients with osteoporosis, which supports the practical role of PINK1 in human bone disease.

Conclusions

In this study, we demonstrated that activation of PINK1 is a requisite in osteoblasts during differentiation, which is related to mitochondrial quality control and low reactive oxygen species production. Enhancing PINK1 activity might be a possible treatment target in bone diseases as it can promote a healthy pool of functional mitochondria in osteoblasts.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02656-4.

Structural, magnetic, and magnetocaloric properties of R2NiMnO6 (R = Eu, Gd, Tb)

The crystal structure, cryogenic magnetic properties, and magnetocaloric performance of double perovskite Eu₂NiMnO₆ (ENMO), Gd₂NiMnO₆ (GNMO), and Tb₂NiMnO₆ (TNMO) ceramic powder samples synthesized by solid-state method have been investigated. X-ray diffraction structural investigation reveal that all compounds crystallize in the monoclinic structure with a P2₁/n space group. A ferromagnetic to paramagnetic (FM-PM) second-order phase transition occurred in ENMO, GNMO, and TNMO at 143, 130, and 112 K, respectively. Maximum magnetic entropy changes and relative cooling power with a 5 T applied magnetic field are determined to be 3.2, 3.8, 3.5 J/kgK and 150, 182, 176 J/kg for the investigated samples, respectively. The change in structural, magnetic, and magnetocaloric effect attributed to the superexchange mechanism of Ni²⁺–O–Mn³⁺ and Ni²⁺–O–Mn⁴⁺. The various atomic sizes of Eu, Gd, and Tb affect the ratio of Mn⁴⁺/Mn³⁺, which is responsible for the considerable change in properties of double perovskite.

Determination of L-Carnitine in Infant Powdered Milk Samples after Derivatization

Herein, a novel analytical method using a high-performance liquid chromatography-fluorescence detector (HPLC/FLD) is developed for rapidly measuring an L-carnitine ester derivative in infant powdered milk. In this study, solid-phase extraction cartridges filled with derivatized methanol and distilled water were used to effectively separate L-carnitine. Protein precipitation pretreatment was carried out to remove the protein and recover the analyte extract with a high recovery (97.16%–106.56%), following which carnitine in the formula was derivatized to its ester form. Precolumn derivation with 1-aminoanthracene (1AA) was carried out in a phosphate buffer using 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) as the catalyst. Method validation was performed following the AOAC guidelines. The calibration curves were linear in the L-carnitine concentration range of 0.1–2.5 mg/L. The lower limit of quantitation and limit of detection of L-carnitine were 0.076 and 0.024 mg/L, respectively. The intra- and interday precision and recovery results were within the allowable limits. The results showed that our method helped reduce the sample preparation time. It also afforded higher resolution and better reproducibility than those obtained by traditional methods. Our method is suitable for detecting the quantity of L-carnitine in infant powdered milk containing a large amount of protein or starch.

Transfer rates of pathogenic bacteria during pork processing

We examined the rates of pathogenic bacterial cross-contamination from gloves to meat and from meat to gloves during pork processing under meat-handling scenarios in transfer rate experiments of inoculated pathogens. The inoculated pork contained ~5-6 Log₁₀ CFU/g pathogenic bacteria like Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), Listeria monocytogenes (L. monocytogenes), and Salmonella enterica subsp. enterica (Sal. enteritidis). On cotton gloves, after cutting the pork, the cutting board, knife, and cotton gloves showed 3.07-3.50, 3.29-3.92 and 4.48-4.86 Log₁₀ CFU/g bacteria. However, when using polyethylene gloves, fewer bacteria (3.12-3.75, 3.20-3.33, and 3.07-3.97 Log₁₀ CFU/g, respectively) were transferred. When four pathogens (6 Log₁₀ CFU/g) were inoculated onto the gloves, polyethylene gloves showed a lower transition rate (cutting board 2.47-3.40, knife 2.01-3.98, and polyethylene glove 2.40-2.98 Log₁₀ CFU/g) than cotton gloves. For cotton gloves, these values were 3.46-3.96, 3.37-4.06, and 3.55-4.00 Log₁₀ CFU/g, respectively. Use of cotton gloves, polyethylene gloves, knives and cutting boards for up to 10 hours in a meat butchering environment has not exceeded HACCP regulations. However, after 10 h of use, 3.09, 3.27, and 2.94 Log₁₀ CFU/g of plate count bacteria were detected on the cotton gloves, cutting board, and knives but polyethylene gloves showed no bacterial count. Our results reveal the transfer efficiency of pathogenic bacteria and that gloved hands may act as a transfer route of pathogenic bacteria between meat and hands. The best hand hygiene was achieved when wearing polyethylene gloves. Thus, use of polyethylene rather than cotton gloves reduces cross-contamination during meat processing.

Growth Differentiation Factor 15 is a Cancer Cell-Induced Mitokine That Primes Thyroid Cancer Cells for Invasiveness

Background: Mitochondrial stress is known to activate the mitochondrial unfolded protein response (UPR^mt). The UPR^mt results in the secretion of mitochondrial cytokines (mitokines), which can promote a hormetic response cell nonautonomously, and has been reported to be protumorigenic. Growth differentiation factor 15 (GDF15) is a well-characterized mitokine, which is reported to have a mitohormetic effect. Thus, we investigated whether GDF15 induction could prime a subpopulation of thyroid cancer cells to provide invasive advantages. Methods: The UPR^mt, including mitokine expression, was assessed in the context of thyroid cancer in vitro and in vivo. GDF15 expression in 266 patients with papillary thyroid carcinoma (PTC) was determined by immunohistochemistry. The serum levels of GDF15 were measured in healthy subjects and PTC patients. In addition, our own and The Cancer Genome Atlas data were analyzed to determine the expression level of GDF15 in thyroid cancers. The role of GDF15 in tumor aggressiveness was investigated by observing the effects of GDF15 knockdown in BCPAP, TPC-1, 8505C, and FRO cells. Results: Pharmacological inhibition of mitochondrial oxidative phosphorylation function in thyroid cancer cells robustly increased GDF15 expression. The expression of GDF15 was associated with activation of the mitochondrial integrated stress response pathway in PTC patients. Circulating GDF15 levels were significantly higher in PTC patients than in the controls, and tumor expression of GDF15 was related to tumor aggressiveness. In vitro and in vivo knockdown of GDF15 in a thyroid cancer model showed decreased viability, migration, and invasion compared with the control cells via regulation of STAT3. Conclusions: In this study, we demonstrated that GDF15 is a mitokine induced in thyroid cancer cells upon mitochondrial stress. GDF15-induced STAT3 activation determined tumor progression in thyroid cancer. The GDF15-STAT3 signaling axis may be a target in aggressiveness of thyroid cancer.

Selenoprotein W ensures physiological bone remodeling by preventing hyperactivity of osteoclasts

Selenoproteins containing selenium in the form of selenocysteine are critical for bone remodeling. However, their underlying mechanism of action is not fully understood. Herein, we report the identification of selenoprotein W (SELENOW) through large-scale mRNA profiling of receptor activator of nuclear factor (NF)-κΒ ligand (RANKL)-induced osteoclast differentiation, as a protein that is downregulated via RANKL/RANK/tumour necrosis factor receptor-associated factor 6/p38 signaling. RNA-sequencing analysis revealed that SELENOW regulates osteoclastogenic genes. SELENOW overexpression enhances osteoclastogenesis in vitro via nuclear translocation of NF-κB and nuclear factor of activated T-cells cytoplasmic 1 mediated by 14-3-3γ, whereas its deficiency suppresses osteoclast formation. SELENOW-deficient and SELENOW-overexpressing mice exhibit high bone mass phenotype and osteoporosis, respectively. Ectopic SELENOW expression stimulates cell-cell fusion critical for osteoclast maturation as well as bone resorption. Thus, RANKL-dependent repression of SELENOW regulates osteoclast differentiation and blocks osteoporosis caused by overactive osteoclasts. These findings demonstrate a biological link between selenium and bone metabolism.

Selenoproteins containing selenium have a variety of physiological functions including redox homeostasis and thyroid hormone metabolism. Here, the authors show that RANKL-dependent repression of selenoprotein W regulates cell fusion during osteoclast differentiation and bone remodelling in mice.

A mechanogenetic role for the actomyosin complex in branching morphogenesis of epithelial organs

The actomyosin complex plays crucial roles in various life processes by balancing the forces generated by cellular components. In addition to its physical function, the actomyosin complex participates in mechanotransduction. However, the exact role of actomyosin contractility in force transmission and the related transcriptional changes during morphogenesis are not fully understood. Here, we report a mechanogenetic role of the actomyosin complex in branching morphogenesis using an organotypic culture system of mouse embryonic submandibular glands. We dissected the physical factors arranged by characteristic actin structures in developing epithelial buds and identified the spatial distribution of forces that is essential for buckling mechanism to promote the branching process. Moreover, the crucial genes required for the distribution of epithelial progenitor cells were regulated by YAP and TAZ through a mechanotransduction process in epithelial organs. These findings are important for our understanding of the physical processes involved in the development of epithelial organs and provide a theoretical background for developing new approaches for organ regeneration.

Development of Pretreatment Method for Analysis of Vitamin B12 in Cereal Infant Formula using Immunoaffinity Chromatography and High-Performance Liquid Chromatography

Vitamin B₁₂ deficiency may lead to serious health issues in both infants and adults. A simple analytical method involving sample pretreatment with enzyme, followed by cyanide addition under acidic conditions; separation on an immunoaffinity column; and high-performance liquid chromatography (HPLC) was developed for the rapid detection and quantitation of vitamin B₁₂ in powdered milk. Detection limit and powdered milk recovery were determined by quantitative analysis. The limits of detection and quantitation were 2.71 and 8.21 μg/L, respectively. Relative standard deviations of the intra-day and inter-day precisions varied in the ranges of 0.98%–5.31% and 2.16%–3.90%, respectively. Recovery of the analysis varied in the range of 83.41%–106.57%, suggesting that the values were acceptable. Additionally, vitamin B₁₂ content and recovery in SRM 1849a were 54.10 μg/kg and 112.24%, respectively. Our results suggested that the analytical method, including the sample pretreatment step, was valid. This analytical method can be implemented in many laboratory-scale experiments that seek to save time and labor. Therefore, this study shows that immunoaffinity–HPLC/ultraviolet is an acceptable technique for constructing a reliable database on vitamin B₁₂ in powdered milk containing starch as well as protein and/or fat in high amounts.

LPS-induced epithelial barrier disruption via hyperactivation of CACC and ENaC

Gram-negative bacterial lipopolysaccharide (LPS) increases the susceptibility of cells to pathogenic diseases, including inflammatory diseases and septic syndrome. In our experiments, we examined whether LPS induces epithelial barrier disruption in secretory epithelia and further investigated its underlying mechanism. The activities of Ca²⁺-activated Cl^- channels (CACC) and epithelial Na⁺ channels (ENaC) were monitored with a short-circuit current using an Ussing chamber. Epithelial membrane integrity was estimated via transepithelial electrical resistance and paracellular permeability assays. We found that the apical application of LPS evoked short-circuit current (I_sc) through the activation of CACC and ENaC. Although LPS disrupted epithelial barrier integrity, this was restored with the inhibition of CACC and ENaC, indicating the role of CACC and ENaC in the regulation of paracellular pathways. We confirmed that LPS, CACC, or ENaC activation evoked apical membrane depolarization. The exposure to a high-K⁺ buffer increased paracellular permeability. LPS induced the rapid redistribution of zonula occludens-1 (ZO-1) and reduced the expression levels of ZO-1 in tight junctions through apical membrane depolarization and tyrosine phosphorylation. However, the LPS-induced epithelial barrier disruption and degradation of ZO-1 were largely recovered by blocking CACC and ENaC. Furthermore, although LPS-impaired epithelial barrier became vulnerable to secondary bacterial infections, this vulnerability was prevented by inhibiting CACC and ENaC. We concluded that LPS induces the disruption of epithelial barrier integrity through the activation of CACC and ENaC, resulting in apical membrane depolarization and the subsequent tyrosine phosphorylation of ZO-1.

Abstract PO-34: Subcutaneous panniculitis-like T-cell lymphoma with HAVCR2 mutation shows unique clinicopathologic features and gene expression profile

Recent studies identified germline HAVCR2 (TIM-3) mutations as the specific genetic predisposition to subcutaneous panniculitis-like T-cell lymphoma (SPTCL). However, distinction between HAVCR2-mutated and HAVCR2-wildtype SPTCLs remains elusive. We studied the prevalence of HAVCR2 mutation in a nation-wide cohort of SPTCL and investigated clinical and molecular distinction between HAVCR2-mutated and HAVCR2-wild-type SPTCLs. A multicenter nationwide cohort of 53 SPTCL cases was established; patients were diagnosed at seven Korean institutions between 2003 and 2020. Histologic features were reviewed by experienced hematopathologists and clinical features were retrospectively reviewed. Whole-exome sequencing (WES) and RNA-seq were performed using formalin-fixed, paraffin-embedded (FFPE) samples of 8 patients diagnosed in Seoul National University Hospital (SNUH), with matched non-neoplastic tissue samples from two patients. Direct sequencing of HAVCR2 exon 2 was successfully carried out using FFPE samples from 33 of the remaining 45 patients. Among 41 patients with available HAVCR2 mutation status, 28 (68.3%) were women, and the median age at diagnosis was 30 years (range 11–74). Ten patients (10/40; 25.0%) suffered hemophagocytic syndrome (HPS) or HPS-like systemic illness during the clinical course, and 14 patients (14/40; 35.0%) progressed during the follow-up. Six patients (6/41; 14.6%) died of disease progression or HPS. We found 18 patients (18/41; 43.9%) with HAVCR2 mutation; 15 patients harbored biallelic HAVCR2 Y82C mutation and 3 patients were noted for heterozygous HAVCR2 Y82C mutation. HAVCR2-mutated SPTCLs occurred in younger patients (median age 26.5 versus 37; Mann-Whitney p-value = 0.003), and were more often complicated by HPS or HPS-like systemic illness (10/18 versus 0/22; Fisher's exact p-value &lt; 0.001), compared to HAVCR2-wild-type SPTCLs. Survival analysis using log-rank test revealed that HAVCR2-mutated SPTCLs had shorter progression-free survival, though statistical significance was not achieved (p-value = 0.081) WES results did not show recurrent genetic alteration other than HAVCR2 Y82C in 4 out of 8 patients. Mutations in genes involved in T/NK cell-associated inflammation (PVRL1, PVRL2, TICAM1, GZMA), epigenetic modification (BAZ2A, KMT2C, KMT2D, SETD1A), JAK-STAT signaling (IFNL2, PIAS3), and NF-kB pathway (PDCD11) were observed in individual cases. Gene set enrichment analyses (GSEA) using RNA-seq results showed significant enrichment of pathways involving TNF-alpha signaling via NF-kB (FDR q-value = 0.008), hypoxia (FDR q-value = 0.009), IL6-JAK-STAT3 signaling (FDR q-value = 0.026), apoptosis (FDR q-value = 0.121), and MTORC1 signaling (FDR q-value = 0.188) in HAVCR2-mutated SPTCLs. HAVCR2 Y82C hotspot mutation frequently occurs in Korean patients with SPTCL, which was characterized by unique clinicopathologic features. SPTCL with HAVCR2 Y82C was enriched with distinct cellular pathways, which remains to be further validated.

Citation Format: Jiwon Koh, Insoon Jang, Seungchan Mun, Cheol Lee, Hee-Jung Cha, Young Ha Oh, Jin Man Kim, Young Hyeh Ko, Jae Ho Han, Heounjeong Go, Jooryung Huh, Kwangsoo Kim, Yoon Kyung Jeon. Subcutaneous panniculitis-like T-cell lymphoma with HAVCR2 mutation shows unique clinicopathologic features and gene expression profile [abstract]. In: Proceedings of the AACR Virtual Meeting: Advances in Malignant Lymphoma; 2020 Aug 17-19. Philadelphia (PA): AACR; Blood Cancer Discov 2020;1(3_Suppl):Abstract nr PO-34.

Determining the Reuse of Frying Oil for Fried Sweet and Sour Pork according to Type of Oil and Frying Time

Food Codex regulations have set freshness limits for oils used to fry food, such as potato and fish products, and fried food itself; however, no such freshness limits have been set for meat products, such as sweet and sour pork. The freshness standard suggest that acid values (AVs) and peroxide values (POVs) for frying oil should be less than 2.5 and 50, respectively, whereas AVs and POVs for common fried food should be less than 5.0 and 60, respectively. Therefore, in this study, we investigate the effect of the number of frying cycles on oxidation-promoted changes in the oils used to fry sweet and sour pork and fried food itself during repeated frying over 10 d by determining their AVs and POVs, which were found to be highly correlated. Soybean, canola, palm, and pork lard oils could be reused approximately 37, 32, 58, and 87 times, respectively, to fry sweet and sour pork based on oil freshness, and 78, 78, 81, and 286 times, respectively, based on the freshness of fried food. Our data may help establish food-quality regulations for oils used to fry animal-based foods.

Slug is a novel molecular target for head and neck squamous cell carcinoma stem-like cells

BACKGROUND

The acquisition of stem-like phenotype is partly attributed to the induction of epithelial-mesenchymal transition (EMT). Thus, the activation of factors involved in EMT can be linked to cancer stem cell genesis. However, the underlying mechanisms in head and neck squamous cell carcinoma (HNSCC) remain largely unknown. Herein, we investigate whether slug, one of the major effectors of EMT, affects the stemness of HNSCC cells.

METHODS

We performed in vitro experiments to determine whether slug gene manipulation can influence the stemness phenotypes, including the capacity for self-renewal, expression of putative stemness markers, chemoresistance, and invasion in HNSCC cells. Further, we identified whether Slug knockout attenuates tumorigenicity of HNSCC cells in vivo. Finally, we examined whether prognosis of HNSCC patients after curative treatment may be affected by the level of slug expression.

RESULTS

Overexpression of slug promoted self-renewal of HNSCC cells via activation of sphere formation, the expression of stem cell markers, and induction of chemoresistance to cisplatin. Also, slug overexpression increased the migration and invasion of HNSCC cells in vitro and was mainly observed during the invasion in HNSCC xenograft mouse model. By contrast, slug expression knockdown abrogated their self-renewal capacity, stemness-associated gene expression, and cisplatin chemoresistance. Furthermore, high levels of slug expression correlated with poor prognosis of patients with HNSCC.

CONCLUSION

Inhibition of slug expression may represent a novel therapeutic strategy targeting HNSCC stem-like cells.

Photoprotective Effect of Dietary Galacto-Oligosaccharide (GOS) in Hairless Mice via Regulation of the MAPK Signaling Pathway

This study investigated the suppression of photoaging by galacto-oligosaccharide (GOS) ingestion following exposure to ultraviolet (UV) radiation. To investigate its photoprotective effects, GOS along with collagen tripeptide (CTP) as a positive control was orally administered to hairless mice under UVB exposure for 8 weeks. The water holding capacity, transepidermal water loss (TEWL), and wrinkle parameters were measured. Additionally, quantitative reverse-transcription polymerase chain reaction and Western blotting were used to determine mRNA expression and protein levels, respectively. The GOS or CTP orally-administered group showed a decreased water holding capacity and increased TEWL compared to those of the control group, which was exposed to UVB (CON) only. In addition, the wrinkle area and mean wrinkle length in the GOS and CTP groups significantly decreased. Skin aging-related genes, matrix metalloproteinase, had significantly different expression levels in the CTP and GOS groups. Additionally, the tissue inhibitor of metalloproteinases and collagen type I gene expression in the CTP and GOS groups significantly increased. Oral administration of GOS and CTP significantly lowered the tissue cytokine (interleukin-6 and -12, and tumor necrosis factor-α) levels. There was a significant difference in UVB-induced phosphorylation of JNK, p38, and ERK between the GOS group and the CON group. Our findings indicate that GOS intake can suppress skin damage caused by UV light and has a UV photoprotective effect.

Alteration of CYP4A11 expression in renal cell carcinoma: diagnostic and prognostic implications

Background: Cytochrome P-450 4A11 (CYP4A11) and peroxisome proliferator-activated receptor-α (PPARα) are expressed at high levels in renal proximal tubules, and upregulation of CYP4A11 protein levels is known to be influenced by PPAR agonists. The goal of this study was to evaluate the clinicopathological role of CYP4A11 expression in renal cell carcinoma (RCC).

Methods: We performed immunohistochemical analysis of CYP4A11, CYP4A22 and PPARα and correlated the results with the clinicopathological features of RCC (n=139). Reverse transcription digital droplet polymerase chain reaction (RT-ddPCR) against CYP4A11 and CYP4A22 was also performed.

Results: CYP4A11 mRNA expression levels were higher in non-neoplastic kidney tissues than in matched tumor tissues in 12 matched pairs of freshly frozen primary clear-cell RCC (ccRCC) and nontumor tissue (p=0.002). Immunohistochemical staining showed that CYP4A11 expression was significantly lower in ccRCC than in non-ccRCCs, including papillary, chromophobe, and unclassified RCCs (p<0.001). CYP4A11 expression was associated with PPARα expression, males and high nuclear histologic grades (p=0.001, p=0.018 and p<0.001). Univariate and multivariate analyses revealed that CYP4A11 expression was correlated with short overall survival (p=0.007 and p=0.010).

Conclusion: These findings suggest that CYP4A11 expression is a potential poor prognostic factor of RCC. The considerable decrease in CYP4A11 expression is a predictive diagnostic factor of ccRCC, and CYP4A11 metabolism in ccRCC might be different from that in non-ccRCCs.

Learning curve of laparoscopic living donor right hepatectomy

Background

The feasibility and learning curve of laparoscopic living donor right hepatectomy was assessed.

Methods

Donors who underwent right hepatectomy performed by a single surgeon were reviewed. Comparisons between open and laparoscopy regarding operative outcomes, including number of bile duct openings in the graft, were performed using propensity score matching.

Results

From 2014 to 2018, 103 and 96 donors underwent laparoscopic and open living donor right hepatectomy respectively, of whom 64 donors from each group were matched. Mean(s.d.) duration of operation (252·2(41·9) versus 304·4(66·5) min; P &lt; 0·001) and median duration of hospital stay (8 versus 10 days; P = 0·002) were shorter in the laparoscopy group. There was no difference in complication rates of donors (P = 0·298) or recipients (P = 0·394) between the two groups. Total time for laparoscopy decreased linearly (R2 = 0·407, β = –0·914, P = 0·001), with the decrease starting after approximately 50 procedures when cases were divided into four quartiles (2nd versus 3rd quartile, P = 0·001; 3rd versus 4th quartile, P = 0·023). Although grafts with bile duct openings were more abundant in the laparoscopy group (P = 0·022), no difference was found in the last two quartiles (P = 0·207).

Conclusion

Laparoscopic living donor right hepatectomy is feasible and an experience of approximately 50 cases may surpass the learning curve.

Impact Of Underlying Pulmonary Diseases On Treatment Outcomes In Early-Stage Non-Small Cell Lung Cancer Treated With Definitive Radiotherapy

Purpose

Current guidelines recommend definitive radiotherapy for patients with medically inoperable early-stage non-small cell lung cancer (NSCLC). However, the impact of underlying pulmonary diseases on survival in those patients remains unclear.

Methods

We retrospectively reviewed the medical records of 234 patients with stage I-II NSCLC treated with definitive radiotherapy alone at Samsung Medical Center between January 2010 and October 2017. We compared survival outcomes according to the presence of underlying pulmonary diseases, including chronic obstructive pulmonary disease (COPD), combined pulmonary fibrosis and emphysema (CPFE), and idiopathic pulmonary fibrosis (IPF). The control group in this study was stage I-II NSCLC patients who were non-COPD, non-CPFE, and non-IPF.

Results

The median follow-up duration was 17 (range, 1–92) months. The median survival times of the control, COPD, CPFE, and IPF groups were 32, 49, 17, and 12 months, respectively (P<0.001). In a Cox proportional hazards analysis for factors associated with overall survival, patients with COPD showed a similar risk of death (adjusted hazard ratio [HR], 1.306; 95% confidence interval [CI], 0.723–2.358; P=0.376) compared to that of the control group, while patients with CPFE (adjusted HR, 3.382; 95% CI, 1.472–7.769; P=0.004) and IPF (adjusted HR, 4.061; 95% CI, 1.963–8.403; P<0.001) showed an increased risk of death.

Conclusion

Definitive radiotherapy may be a tolerable treatment for early-stage NSCLC with COPD. However, poor survival in early-stage NSCLC patients with IPF or CPFE requires further study to identify and develop patient selection criteria as well as an optimal radiotherapy modality.

3D cellular visualization of intact mouse tooth using optical clearing without decalcification

Dental pulp is composed of nerves, blood vessels, and various types of cells and surrounded by a thick and hard enamel-dentin matrix. Due to its importance in the maintenance of tooth vitality, there have been intensive efforts to analyze the complex cellular-level organization of the dental pulp in teeth. Although conventional histologic analysis has provided microscopic images of the dental pulp, 3-dimensional (3D) cellular-level visualization of the whole dental pulp in an intact tooth has remained a technically challenging task. This is mainly due to the inevitable disruption and loss of microscopic structural features during the process of mechanical sectioning required for the preparation of the tooth sample for histological observation. To accomplish 3D microscopic observation of thick intact tissue, various optical clearing techniques have been developed mostly for soft tissue, and their application for hard tissues such as bone and teeth has only recently started to be investigated. In this work, we established a simple and rapid optical clearing technique for intact mouse teeth without the time-consuming process of decalcification. We achieved 3D cellular-level visualization of the microvasculature and various immune cell distributions in the whole dental pulp of mouse teeth under normal and pathologic conditions. This technique could be used to enable diverse research methods on tooth development and regeneration by providing 3D visualization of various pulpal cells in intact mouse teeth.

ALK-positive anaplastic large cell lymphoma with a monomorphic small-cell pattern masquerading as inflammatory gastric lesions

INTRODUCTION

Anaplastic lymphoma kinase-positive (ALK+) anaplastic large cell lymphoma (ALCL) with a non-common pattern can be diagnostic challenging. Pathologists can be unavoidably and unintentionally blind to non-descript tumor cells in a lymphohistiocytic- (LH) or small-cell (SC)-pattern. We report a case of primary systemic ALK+ ALCL with a SC pattern that presented as secondary gastric lesions with a mixed LH and SC pattern that was masqueraded as inflammatory lesions.

CASE REPORT

A 34-year-old woman with intractable epigastric pain was referred to have repeated endoscopy with biopsy. She was found to multiple gastric erosions and nodules that were diagnosed as inflammatory lesions both endoscopically and histologically. Meanwhile, she developed an acute onset of severe back pain associated with a pathologic compression fracture in the T3 thoracic vertebral body. Imaging studies disclosed a disseminated systemic disease involving abdominopelvic lymph nodes and cervical and thoracic vertebral bodies. The needle biopsy of the pelvic lymph node disclosed diffuse proliferation of monomorphic small round cells that were diffusely positive for CD30 and ALK. A diagnosis of ALK+ ALCL with a monomorphic SC pattern was rendered.

DISCUSSION

A retrospective review of the gastric biopsies with the aid of immunohistochemistry enabled us to recognise the presence of lymphomatous infiltrates with a mixed LH and SC pattern in every piece of gastric biopsies that were repeatedly misdiagnosed as inflammatory lesions. This case illustrates a significant diagnostic pitfall of the LH- and SC-patterns in ALK+ ALCL, in which the tumour cells featuring lymphoid, plasmacytoid or histiocytoid appearance can be masqueraded as inflammatory cells.

Immunohistochemical expression of CD44, matrix metalloproteinase2 and matrix metalloproteinase9 in renal cell carcinomas

PURPOSE

The aim of our study was to investigate the clinicopathologic values of the expression of CD44, matrix metalloproteinase (MMP)2, and MMP9 in renal cell carcinoma (RCC).

PATIENTS AND METHODS

A total of 107 clear cell RCCs (ccRCCs) and 32 nonclear cell RCCs (non-ccRCCs) were examined for CD44, MMP2, and MMP9 expression by immunohistochemistry. The membrane and cytoplasmic expression levels of the 3 proteins were scored by semiquantitative methods, and the correlations of the 3 proteins with clinicopathological parameters were verified.

RESULTS

The expression levels of CD44, MMP2, and MMP9 were positively correlated with nuclear grade (grade 1-2 vs. grade 3-4) (P = 0.003, P < 0.001 and P < 0.001, respectively) in the ccRCCs, while in the non-ccRCCs, only CD44 expression was correlated with higher nuclear grade (grade 1-3 vs. grade 4) (P = 0.001). Furthermore, CD44 expression in ccRCCs and non-ccRCCs was correlated with shorter overall survival in the univariate analyses (P < 0.001 and P = 0.015, respectively). In the multivariate analysis, which accounted for age, sex, nuclear grade, and pathologic stage, CD44 expression was an independent predictor of shorter overall survival only in ccRCCs. Correlations among the 3 proteins were all positive in ccRCCs, but in non-ccRCCs, only MMP2 and MMP9 were positively correlated.

CONCLUSION

CD44 expression may play an important role in the progression of both ccRCC and non-ccRCC. CD44 expression in ccRCC may be associated with elevated MMP2 and MMP9 expression levels, which is in contrast to non-ccRCC. The different correlations between CD44, MMP2, and MMP9 in ccRCC and non-ccRCC can be useful in understanding the mechanisms of carcinogenesis and stratifying patients for therapeutic purposes.

Cationic amino acid transporter PQLC2 is a potential therapeutic target in gastric cancer

Tumor cells overexpress amino acid transporters to meet the increased demand for amino acids. PQ loop repeat‐containing (PQLC)2 is a cationic amino acid transporter that might be involved in cancer progression. Here, we show that upregulation of PQLC2 is critical to gastric cancer (GC) development in vitro and in vivo. Both PQLC2 mRNA and protein were overexpressed in GC tissues, especially of the diffuse type. Overexpression of PQLC2 promoted cell growth, anchorage independence, and tumor formation in nude mice. This was due to activation of MEK/ERK1/2 and PI3K/AKT signaling. Conversely, PQLC2 knockdown caused growth arrest and cell death of cancer cells and suppressed tumor growth in a mouse xenograft model. These results suggest that targeting PQLC2 is an effective strategy for GC treatment.

LAMB3 is associated with disease progression and cisplatin cytotoxic sensitivity in head and neck squamous cell carcinoma

OBJECTIVES

Laminin subunit beta-3 (LAMB3) is a major component of the basement membrane zone. In our study, we investigated the role of LAMB3 in head and neck squamous cell carcinoma (HNSCC) progression and its clinical implication as a prognostic biomarker.

MATERIALS AND METHODS

A retrospective analysis of 100 patients with HNSCC who had undergone curative surgery from 1999 to 2011 was performed. We evaluated LAMB3 expression by immunohistochemistry and its associations with clinicopathological characteristics and survival. For functional in vitro analyses, cell proliferation, migration, and invasion and western blot assays were performed following LAMB3 suppression. In addition, the role of LAMB3 in cisplatin-induced cytotoxicity was clarified by measuring cell proliferation.

RESULTS

LAMB3 expression was up-regulated in HNSCC cell lines and patient tissues. High LAMB3 expression was significantly associated with positive lymph node metastasis (odds ratio: 6.316; P < 0.001) and poor prognosis in patients with HNSCC. LAMB3 suppression reduced cell migration/invasion via down-regulation of epithelial-to-mesenchymal transition-associated proteins (Vimentin and Slug). Moreover, LAMB3 suppression increased cisplatin cytotoxicity in HNSCC cells.

CONCLUSION

Our findings indicate that LAMB3 may be used as a prognostic biomarker in HNSCC and support that LAMB3 silencing could induce the sensitivity of anti-cancer drugs such as cisplatin.

Acquisition of Carbapenemase-Producing Enterobacteriaceae in Solid Organ Transplantation Recipients

BACKGROUND

Carbapenemase-producing Enterobacteriaceae (CPE) can lead to life-threatening outcomes with rapid spread of the carbapenemase gene in solid organ transplantation (SOT) recipients because of limitations of available antibiotics. We examined the characteristics and importance of CPE acquisition in SOT recipients with large numbers of CPE isolates.

METHODS

Between November 2015 and October 2016, 584 CPE isolates were found in 37 recipients and verified by carbapenemase gene multiplex polymerase chain reaction (PCR). One hundred recipients with at least 2 negative results in carbapenemase PCR for stool surveillance and no CPE isolates in clinical samples were retrospectively included.

RESULTS

Most CPE isolates were Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (546, 93.5%). The most frequent transplantation organ was lung (43.3%), and the most common sample with CPE isolates other than stool was respiratory tract (22.6%). The median time between SOT and first CPE acquisition was 7 days. All-cause mortality was significantly higher in recipients with CPE than in those without CPE (24.3% vs 10.0%; P = .03). In multivariate regression analysis, stool colonization of vancomycin-resistant Enterococci and/or Clostridium difficile during 30 days before SOT (odds ratio [OR], 3.28; 95% CI, 1.24-8.68; P = .02), lung transplantation (OR, 4.50; 95% CI, 1.19-17.03; P = .03), and intensive care unit stay ≥2 weeks (OR, 6.21; 95% CI, 1.72-22.45; P = .005) were associated with acquisition of CPE.

CONCLUSIONS

Early posttransplantation CPE acquisition may affect the clinical outcome of SOT recipients. Careful screening for CPE during the early posttransplantation period would be meaningful in recipients with risk factors.

Correction: RCP induces Slug expression and cancer cell invasion by stabilizing β1 integrin

Following the publication of this article the authors noted that images were inadvertently duplicated in Fig. 1b. The corrected Fig. 1 can be found in the associated Correction. The conclusions of this paper are not affected. The authors sincerely apologize for this error. This error has not been corrected in the HTML or PDF of the original Article.

Predictors of incisional hernia in adult liver transplant recipients

PURPOSE

Incisional hernia is a complication following abdominal operation. Patients undergoing liver transplantation have a high risk of developing incisional hernia because of immunosuppression. The purpose of this study was to evaluate incisional hernia after liver transplantation and to identify risk factors for hernia formation in those patients.

METHODS

We retrospectively reviewed 1044 adult patients with more than 2 years of follow-up in patients who underwent liver transplantation from January 2000 to December 2015.

RESULTS

Incisional hernia was identified in 79 patients with more than 2 years of follow-up. The overall incisional hernia rate was 7.6%. The mean age and body mass index (BMI) of the patients with incisional hernia were 55 ± 9 years and 25.3 ± 3.7 kg/m², respectively. No significant differences in gender, diagnosis, diabetes, Child-Pugh score, model for end-stage liver disease (MELD) score, donor type, hepatorenal syndrome, varix bleeding, ascites, hepatic encephalopathy, ventilator use, spontaneous bacterial peritonitis (SBP), or bile leakage were found between patients who did and did not develop incisional hernia. Patients with acute rejection before hernia development were more to have herniated patients hernia (p < 0.05).

CONCLUSION

Age greater than 55 years and high BMI were significant risk factors. We identified risk factors for the development of incisional hernia. Based on these risk factors, attention should be paid to incisional hernia in older and obese patients.

Laparoscopic right posterior sectionectomy versus laparoscopic right hemihepatectomy for hepatocellular carcinoma in posterior segments: Propensity Score Matching Analysis

BACKGROUND AND AIMS:

This study was designed to analyze the feasibility of laparoscopic right posterior sectionectomy compared to laparoscopic right hemihepatectomy in patients with hepatocellular carcinoma located in the posterior segments.

MATERIAL AND METHODS:

The study included patients who underwent either laparoscopic right posterior sectionectomy or laparoscopic right hemihepatectomy for hepatocellular carcinoma located in segment 6 or 7 from January 2009 to December 2016 at Samsung Medical Center. After 1:1 propensity score matching, patient baseline characteristics and operative and postoperative outcomes were compared between the two groups. Disease-free survival and overall survival were compared using Kaplan-Meier log-rank test.

RESULTS:

Among 61 patients with laparoscopic right posterior sectionectomy and 37 patients with laparoscopic right hemihepatectomy, 30 patients from each group were analyzed after propensity score matching. After matching, baseline characteristics of the two groups were similar including tumor size (3.4 ± 1.2 cm in laparoscopic right posterior sectionectomy vs 3.7 ± 2.1 cm in laparoscopic right hemihepatectomy, P = 0.483); differences were significant before matching (3.1 ± 1.3 cm in laparoscopic right posterior sectionectomy vs 4.3 ± 2.7 cm in laparoscopic right hemihepatectomy, P = 0.035). No significant differences were observed in operative and postoperative data except for free margin size (1.04 ± 0.71 cm in laparoscopic right posterior sectionectomy vs 2.95 ± 1.75 cm in laparoscopic right hemihepatectomy, P < 0.001). Disease-free survival (5-year survival: 38.0% in laparoscopic right posterior sectionectomy vs 47.0% in laparoscopic right hemihepatectomy, P = 0.510) and overall survival (5-year survival: 92.7% in laparoscopic right posterior sectionectomy vs 89.6% in laparoscopic right hemihepatectomy, P = 0.593) did not differ between the groups based on Kaplan-Meier log-rank test.

CONCLUSION:

For hepatocellular carcinoma in the posterior segments, laparoscopic right posterior sectionectomy was feasible compared to laparoscopic right hemihepatectomy when performed by experienced laparoscopic surgeons.