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ObjectiveRecently, we demonstrated cholesterol accelerating colorectal cancer (CRC) progression via squalene epoxidase (SQLE) reduction, activating the β-catenin oncogenic pathway while downregulating the p53 pathway, mediated by the inhibition of GSK3β activity (GSK3βpS9). However, the interrelationship between cholesterol increase and CRC progression with aging has never been determined.DesignWe utilized case data from public databases and human specimens to assess the relationship between cholesterol accumulation and CRC progression with aging. Digital image analysis-machine learning with multiplex fluorescence-immunohistochemistry evaluated the effects of SQLE, p53WT, p53MT, and GSK3βpS9(hereafter candidates) on the survival of CRC patients. Also, the prognostic and diagnostic abilities were assessed by a time-dependent receiver operating characteristic (timeROC) and a ROC curve with and without the discriminant score for the candidates as a single or whole, respectively.ResultsWe found an accumulation of cholesterol and cholesteryl ester in tissues with aging, which led to the acceleration of CRC progression through substantial decreases of SQLE, p53WT, p53MTexpressions and inhibition of GSK3β activity in advanced CRCs. Retrospective studies demonstrated that SQLE significantly impacted the shortened progression-free survival of the population with progressive pathological severity and high CRC risk beyond the age of 50. Clinical assays further showed the excellent prognostic and diagnostic abilities of SQLE and GSK3βpS9but also the substantial diagnostic potential of the combined candidate for the aged high-risk CRC population.ConclusionWe provide new insights into the relationship between cholesterol increase and CRC progression with aging and identify valuable biomarkers for aged populations with high-risk CRC.

TREX1 is an exonuclease that degrades extranuclear DNA species in mammalian cells. Herein, we show a novel mechanism by which TREX1 interacts with the BiP/GRP78 and TREX1 deficiency triggers ER stress through the accumulation of single-stranded DNA and activates unfolded protein response (UPR) signaling via the disruption of the TREX1-BiP/GRP78 interaction. In TREX1 knockdown cells, the activation of ER stress signaling disrupted ER Ca2+ homeostasis via the ERO1α-IP3R1-CaMKII pathway, leading to neuronal cell death. Moreover, TREX1 knockdown dysregulated the Golgi-microtubule network through Golgi fragmentation and decreased Ac-α-tubulin levels, contributing to neuronal injury. These alterations were also observed in neuronal cells harboring a TREX1 mutation (V91M) that has been identified in hereditary spastic paraplegia (HSP) patients in Korea. Notably, this mutation leads to defects in the TREX1-BiP/GRP78 interaction and mislocalization of TREX1 from the ER and possible disruption of the Golgi-microtubule network. In summary, the current study reveals TREX1 as a novel regulator of the BiP/GRP78 interaction and shows that TREX1 deficiency promotes ER stress-mediated neuronal cell death, which indicates that TREX1 may hold promise as a therapeutic target for neurodegenerative diseases such as HSP.

Aim: Lennox-Gastaut syndrome (LGS) is a severe type of childhood-onset epilepsy with multiple types of seizures, specific discharges on electroencephalography, and intellectual disability. However, LGS-related genes are largely unknown. To identify causative genes related to LGS, we collected and analyzed data from a three-generation Korean family in which one member had LGS and two had intellectual disability. Methods: Genomic DNAs were extracted from blood samples of all participants and used in whole-exome sequencing (WES). Genetic variants were detected by the Genome Analysis Toolkit and confirmed by Sanger sequencing. Variant pathogenicity was evaluated by prediction programs and the American College of Medical Genetics criteria. The LGS patient had generalized slow spike-and-wave discharges, multiple types of seizures, and developmental delay. Results: Analyses of the WES data from the family revealed a novel variant (c.1048G>A, p.Ala350Thr) in the IQ motif and Sec7 domain 2 (IQSEC2). This variant is within a highly evolutionarily conserved IQ-like motif, indicating a decrease in the calmodulin-binding capacity or α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid transmission. The hemizygous variant in the male with LGS was a maternally inherited X-linked variant from the heterozygous maternal grandmother and mother, both of whom had intellectual disability. Conclusion: These findings indicate that the variant of IQSEC2 triggered both LGS and intellectual disability dependent on sex in this family. We report a novel X-linked inherited IQSEC2 variant for LGS and intellectual disability, which enhances the spectrum of variants in the IQ-like motif of IQSEC2.

Studies have reported dysregulation of TIPRL, LC3 and CD133 in liver cancer tissues. However, their respective relationships to liver cancer and roles as biomarkers for prognosis and diagnosis of liver cancer have never been studied. Here we report that the level of TIPRL is significantly correlated with levels of LC3 (Spearman r = 0.9) and CD133 (r = 0.7) in liver cancer tissues. We observed significant upregulations of TIPRL, LC3 and CD133 in hepatocellular carcinomas (HCCs) compared with adjacent normal tissues. Importantly, TIPRL, tested among additional variables, showed a significant impact on the prognosis of HCC patients. TIPRL knockdown significantly reduced expressions of LC3, CD133, stemness-related genes, as well as viability and stemness of liver cancer cell-lines, which were promoted by ectopic TIPRL expression. Either alone or as a combination, TIPRL, LC3 and CD133 showed significant values of area under the curve (AUC) and sensitivity/specificity in early liver cancer tissues. Furthermore, the statistical association and the diagnostic efficacies of TIPRL, LC3 and CD133 in HCC tissues were confirmed in a different IHC cohort. This data demonstrates that the complex involvement of TIPRL/LC3/CD133 in liver cancer aggressiveness can together or individually serve as potential biomarkers for the early detection of liver cancer.

Simple Summary We recently reported that the human TOR signaling regulator (hereafter TIPRL) contributes to the drug-resistance of hepatocellular carcinomas (HCCs) and the involvement of TIPRL/LC3/CD133 in liver cancer aggressiveness. This study aims to determine prognostic and diagnostic efficacies of TIPRL/LC3/CD133/CD44 for early liver cancer. We observed the significant upregulation of TIPRL and LC3 in HCCs and adult hepatocyte-derived liver disease while observing downregulation in intrahepatic carcinomas (iCCA). The TIPRL level has been shown to be the clearest indicator of liver cancer patients’ survivability as a sole covariate. This indication supports that TIPRL contributed to liver cancer cell proliferation and survival via stemness and self-renewal induction. TIPRL/LC3/CD133 have exhibited crucial efficiency in diagnostic patients with grade 1 iCCA, and TIPRL/LC3/CD133/CD44 showed prognosticating grade-1 HCCs and iCCA, either as an alone or in conjunction. Overall, this study reports that TIPRL/LC3/CD133/CD44 could, either individually or in conjunction, serve as potential biomarkers for early liver cancer. Abstract Recently, we reported the involvement of TIPRL/LC3/CD133 in liver cancer aggressiveness. This study assessed the human TOR signaling regulator (TIPRL)/microtubule-associated light chain 3 (LC3)/prominin-1 (CD133)/cluster of differentiation 44 (CD44) as potential diagnostic and prognostic biomarkers for early liver cancer. For the assessment, we stained tissues of human liver disease/cancer with antibodies against TIPRL/LC3/CD133/CD44/CD46, followed by confocal observation. The roles of TIPRL/LC3/CD133/CD44/CD46 in liver normal and cancer cell lines were determined by in vitro studies. We analyzed the prognostic and diagnostic potentials of TIPRL/LC3/CD133/CD44/CD46 using the receiver-operating characteristic curve, a Kaplan–Meier and uni-/multi-Cox analyses. TIPRL and LC3 were upregulated in tissues of HCCs and adult hepatocytes-derived liver diseases while downregulated in iCCA. Intriguingly, TIPRL levels were found to be critically associated with liver cancer patients’ survivability, and TIPRL is the key player in liver cancer cell proliferation and viability via stemness and self-renewal induction. Furthermore, we demonstrate that TIPRL/LC3/CD133 have shown prominent efficiency for diagnosing patients with grade 1 iCCA. TIPRL/LC3/CD133/CD44 have also provided excellent potential for prognosticating patients with grade 1 iCCA and grade 1 HCCs, together with demonstrating that TIPRL/LC3/CD133/CD44 are, either individually or in conjunction, potential biomarkers for early liver cancer.

Hereditary Spastic Paraplegias (HSP) are a group of rare inherited neurological disorders characterized by progressive loss of corticospinal motor-tract function. Numerous patients with HSP remain undiagnosed despite screening for known genetic causes of HSP. Therefore, identification of novel genetic variations related to HSP is needed. In this study, we identified 88 genetic variants in 54 genes from whole-exome data of 82 clinically well-defined Korean HSP families. Fifty-six percent were known HSP genes, and 44% were composed of putative candidate HSP genes involved in the HSPome and originally reported neuron-related genes, not previously diagnosed in HSP patients. Their inheritance modes were 39, de novo; 33, autosomal dominant; and 10, autosomal recessive. Notably, ALDH18A1 showed the second highest frequency. Fourteen known HSP genes were firstly reported in Koreans, with some of their variants being predictive of HSP-causing protein malfunction. SPAST and REEP1 mutants with unknown function induced neurite abnormality. Further, 54 HSP-related genes were closely linked to the HSP progression-related network. Additionally, the genetic spectrum and variation of known HSP genes differed across ethnic groups. These results expand the genetic spectrum for HSP and may contribute to the accurate diagnosis and treatment for rare HSP.

TREX1 is an exonuclease that degrades extranuclear DNA species in mammalian cells. Herein, we show a novel mechanism by which TREX1 interacts with the BiP/GRP78 and TREX1 deficiency triggers ER stress through the accumulation of single-stranded DNA and activates unfolded protein response (UPR) signaling via the disruption of the TREX1-BiP/GRP78 interaction. In TREX1 knockdown cells, the activation of ER stress signaling disrupted ER Ca

// Ji-Yong Yoon 1, * , Jeong-Ju Lee 1, * , Sujin Gu 2 , Myoung Eun Jung 2 , Hyun-Soo Cho 1, 4 , Jung Hwa Lim 3, 4 , Soo Young Jun 1, 4 , Jun-Ho Ahn 1 , Ju-Sik Min 1 , Min-Hyuk Choi 1, 4 , Su-Jin Jeon 1, 4 , Yong-Jae Lee 1 , Areum Go 2, 5 , Yun-Jeong Heo 2 , Cho-Rok Jung 3, 4 , Gildon Choi 2, 5 , Kwangho Lee 2, 5 , Moon-Kook Jeon 2 and Nam-Soon Kim 1, 4 1 Genome Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 305-333, Republic of Korea 2 Bio and Drug Discovery Division, Korea Research Institute of Chemical Technology, Daejeon, 34114, Republic of Korea 3 Gene Therapy Research Unit, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 305-333, Republic of Korea 4 Department of Functional Genomics, Korea University of Science and Technology, Daejeon, 34113, Republic of Korea 5 Medicinal Chemistry and Pharmacology, Korea University of Science and Technology, Daejeon, 34113, Republic of Korea * Co-first authors Correspondence to: Nam-Soon Kim, email: nskim37@kribb.re.kr Moon-Kook Jeon, email: moteta@krict.re.kr Keywords: TIPRL, apoptosis, HCC, TRAIL sensitizer Received: January 25, 2017 Accepted: September 29, 2017 Published: November 03, 2017 ABSTRACT Hepatocellular carcinoma (HCC) is one of the most malignant tumors. Although various treatments, such as surgery and chemotherapy, have been developed, a novel alternative therapeutic approach for HCC therapy is urgently needed. Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) is a promising anti-cancer agent, but many cancer cells are resistant to TRAIL-induced apoptosis. To help overcome TRAIL resistance in HCC cancer cells, we have identified novel chemical compounds that act as TRAIL sensitizers. We first identified the hit compound, TRT-0002, from a chemical library of 6,000 compounds using a previously developed high-throughput enzyme-linked immunosorbent assay (ELISA) screening system, which was based on the interaction of mitogen-activated protein kinase kinase 7 (MKK7) and TOR signaling pathway regulator-like (TIPRL) proteins and a cell viability assay. To increase the efficacy of this TRAIL sensitizer, we synthesized 280 analogs of TRT-0002 and finally identified two lead compounds (TRT-0029 and TRT-0173). Co-treating cultured Huh7 cells with either TRT-0029 or TRT-0173 and TRAIL resulted in TRAIL-induced apoptosis due to the inhibition of the MKK7-TIPRL interaction and subsequent phosphorylation of MKK7 and c-Jun N-terminal kinase (JNK). In vivo , injection of these compounds and TRAIL into HCC xenograft tumors resulted in tumor regression. Taken together, our results suggest that the identified lead compounds serve as TRAIL sensitizers and represent a novel strategy to overcome TRAIL resistance in HCC.

The coiled-coil domain containing 50 (CCDC50) protein is a phosphotyrosine-dependent signalling protein stimulated by epidermal growth factor. It is highly expressed in neuronal cells in the central nervous system; however, the roles of CCDC50 in neuronal development are largely unknown. In this study, we showed that the depletion of CCDC50-V2 impeded the neuronal development process, including arbor formation, spine density development, and axonal outgrowth, in primary neurons. Mechanistic studies revealed that CCDC50-V2 positively regulated the nerve growth factor receptor, while it downregulated the epidermal growth factor receptor pathway. Importantly, JNK/c-Jun activation was found to be induced by the CCDC50-V2 overexpression, in which the interaction between CCDC50-V2 and JNK2 was also observed. Overall, the present study demonstrates a novel mechanism of CCDC50 function in neuronal development and provides new insight into the link between CCDC50 function and the aetiology of neurological disorders.

Autophagy, an intracellular system of degrading damaged organelles and misfolded proteins, is essential for cancer cell survival. Despite the progress made towards understanding the mechanism, identification of novel autophagy regulators presents a major obstacle in developing anticancer therapies. Here, we examine the association between the TOR signaling pathway regulator-like (TIPRL) protein and autophagy in malignant transformation of tumors. We show that TIPRL upregulation in non-small cell lung cancer (NSCLC) potentiated autophagy activity and enabled autophagic clearance of metabolic and cellular stress, conferring a survival advantage to cancer cells. Importantly, the interaction of TIPRL with eukaryotic initiation factor 2α (eIF2α) led to eIF2α phosphorylation and activation of the eIF2α-ATF4 pathway, thereby inducing autophagy. Conversely, TIPRL depletion increased apoptosis by reducing autophagic clearance, which was markedly enhanced in TIPRL-depleted A549 xenografts treated with 2-deoxy-D-glucose. Overall, the study indicated that TIPRL is a potential regulator of autophagy and an important drug target for lung cancer therapy.

Background & Aims Squalene epoxidase (SQLE), a rate-limiting enzyme in cholesterol biosynthesis, is suggested as a proto-oncogene. Paradoxically, SQLE is degraded by excess cholesterol, and low SQLE is associated with aggressive colorectal cancer (CRC). Therefore, we studied the functional consequences of SQLE reduction in CRC progression. Methods Gene and protein expression data and clinical features of CRCs were obtained from public databases and 293 human tissues, analyzed by immunohistochemistry. In vitro studies showed underlying mechanisms of CRC progression mediated by SQLE reduction. Mice were fed a 2% high-cholesterol or a control diet before and after cecum implantation of SQLE genetic knockdown/control CRC cells. Metastatic dissemination and circulating cancer stem cells were demonstrated by in vivo tracking and flow cytometry analysis, respectively. Results In vitro studies showed that SQLE reduction helped cancer cells overcome constraints by inducing the epithelial-mesenchymal transition required to generate cancer stem cells. Surprisingly, SQLE interacted with GSK3β and p53. Active GSK3β contributes to the stability of SQLE, thereby increasing cell cholesterol content, whereas SQLE depletion disrupted the GSK3β/p53 complex, resulting in a metastatic phenotype. This was confirmed in a spontaneous CRC metastasis mice model, where SQLE reduction, by a high-cholesterol regimen or genetic knockdown, strikingly promoted CRC aggressiveness through the production of migratory cancer stem cells. Conclusions We showed that SQLE reduction caused by cholesterol accumulation aggravates CRC progression via the activation of the β-catenin oncogenic pathway and deactivation of the p53 tumor suppressor pathway. Our findings provide new insights into the link between cholesterol and CRC, identifying SQLE as a key regulator in CRC aggressiveness and a prognostic biomarker.

// Jae-Hye Lee 1, 3, * , Hyun-Soo Cho 1, 3, * , Jeong-Ju Lee 1 , Soo Young Jun 1, 3 , Jun-Ho Ahn 1 , Ju-Sik Min 1 , Ji-Yong Yoon 1 , Min-Hyuk Choi 1, 3 , Su-Jin Jeon 1, 3 , Jung Hwa Lim 2 , Cho-Rok Jung 2 , Dae-Soo Kim 1, 3 , Hyun-Taek Kim 4 , Valentina M. Factor 5 , Yun-Han Lee 6 , Snorri S. Thorgeirsson 7 , Cheol-Hee Kim 4 , Nam-Soon Kim 1, 3 1 Genome Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-333, Republic of Korea 2 Gene Therapy Research Unit, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-333, Republic of Korea 3 Department of Functional Genomics, Korea University of Science and Technology, Daejeon 305-333, Republic of Korea 4 Department of Biology, Chungnam National University, Daejeon 305-764, Republic of Korea 5 Laboratory of Molecular Pharmacology, Center for Cancer Research, NCI, NIH, Bethesda, MD 20892-5068, USA 6 Department of Molecular Medicine, Keimyung University School of Medicine, Daegu 704-701, Republic of Korea 7 Laboratory of Human Carcinogenesis, Center for Cancer Research, NCI, NIH, Bethesda, MD 20892-4255, USA * Both authors are shared co-first authorship Correspondence to: Nam-Soon Kim, email: nskim37@kribb.re.kr Keywords: liver cancer, metastasis, PGCP, Wnt/β-catenin Received: July 25, 2016 Accepted: October 14, 2016 Published: October 28, 2016 ABSTRACT Tumor metastasis is the leading cause of cancer death. In the metastatic process, EMT is a unique phenotypic change that plays an important role in cell invasion and changes in cell morphology. Despite the clinical significance, the mechanism underlying tumor metastasis is still poorly understood. Here we report a novel mechanism by which secreted plasma glutamate carboxypeptidase(PGCP) negatively involves Wnt/β-catenin signaling by DKK4 regulation in liver cancer metastasis. Pathway analysis of the RNA sequencing data showed that PGCP knockdown in liver cancer cell lines enriched the functions of cell migration, motility and mesenchymal cell differentiation. Depletion of PGCP promoted cell migration and invasion via activation of Wnt/β-catenin signaling pathway components such as phospho-LRP6 and β-catenin. Also, addition of DKK4 antagonized the Wnt/β-catenin signaling cascade in a thyroxine (T4)-dependent manner. In an in vivo study, metastatic nodules were observed in the lungs of the mice after injection of shPGCP stable cell lines. Our findings suggest that PGCP negatively associates with Wnt/β-catenin signaling during metastasis. Targeting this regulation may represent a novel and effective therapeutic option for liver cancer by preventing metastatic activity of primary tumor cells.

TRAIL (TNF-related apoptosis inducing ligand) is a promising anti-cancer drug target that selectively induces apoptosis in cancer cells. However, many cancer cells are resistant to TRAIL-induced apoptosis. Therefore, reversing TRAIL resistance is an important step for the development of effective TRAIL-based anti-cancer therapies. We previously reported that knockdown of the TOR signaling pathway regulator-like (TIPRL) protein caused TRAIL-induced apoptosis by activation of the MKK7-c-Jun N-terminal Kinase (JNK) pathway through disruption of the MKK7-TIPRL interaction. Here, we identified Taraxacum officinale F.H. Wigg (TO) as a novel TRAIL sensitizer from a set of 500 natural products using an ELISA system and validated its activity by GST pull-down analysis. Furthermore, combination treatment of Huh7 cells with TRAIL and TO resulted in TRAIL-induced apoptosis mediated through inhibition of the MKK7-TIPRL interaction and subsequent activation of MKK7-JNK phosphorylation. Interestingly, HPLC analysis identified chicoric acid as a major component of the TO extract, and combination treatment with chicoric acid and TRAIL induced TRAIL-induced cell apoptosis via JNK activation due to inhibition of the MKK7-TIPRL interaction. Our results suggest that TO plays an important role in TRAIL-induced apoptosis, and further functional studies are warranted to confirm the importance of TO as a novel TRAIL sensitizer for cancer therapy. © 2015 Wiley Periodicals, Inc.

Induction of apoptosis through activation of the TRAIL pathway is considered to be a promising anticancer strategy due to its ability to selectively induce apoptosis in cancer cells. However, the ability of cancer cells to acquire TRAIL resistance has limited the clinical translation of this approach. We previously reported that the TOR signaling pathway regulator-like (TIPRL) protein contributes to the resistance to TRAIL-induced apoptosis by inhibiting the MKK7-c-Jun N-terminal kinase (JNK) pathway via MKK7‑TIPRL interaction. In the present study, we identified Tussilago farfara L. (TF) as a novel TRAIL sensitizer among 500 natural products using an ELISA system that specifically detects the MKK7-TIPRL interaction, and we validated candidates by GST-pull down assay. Co-treatment of Huh7 cells with TF and TRAIL induced apoptosis via inhibition of the MKK7-TIPRL interaction and an increase in MKK7/JNK phosphorylation. This is the first report to describe TF as a novel TRAIL sensitizer, unveiling a potentially novel therapeutic strategy in cancer therapy.

Links between cholesterol and cancer are well-documented, but the mechanisms remain unclear. Squalene epoxidase (SQLE), a key enzyme in cholesterol biosynthesis degraded by excess cholesterol, is suggested as a proto-oncogene. Paradoxically, we found reduced SQLE in aggressive colorectal cancer (CRC); low SQLE being associated with a shortened survival of CRC patients. This was confirmed in a spontaneous CRC metastasis mouse model where SL-15 reduction, by either a high-cholesterol regimen or genetic knockdown, strikingly promotes CRC aggressiveness through the production of migratory cancer stem cells. Experiments in CRC cell-lines demonstrated that SQLE reduction helps overcome constraints for malignant transformation. Specifically, we uncovered a surprising interaction of SQLE with GSK3β and p53. Depletion of SQLE disrupted the GSK3β/p53 complex, resulting in a metastatic phenotype. Our findings provide mechanistic insights into the link between cholesterol and CRC, identifying SQLE as a key regulator in CRC progression and potentially a biomarker for risk assessment. Citation Format: Soo Young Jun, Andrew J. Brown, Ji-Yong Yoon, Jeong-Ju Lee, Ngee Kiat Chua, Jin OK Yang, Ju-Sik Min, Insu Jang, Su-Jin Jeon, Min-Hyuk Choi, Tae-Ik Choi, Cheol-Hee Kim, Nam-Soon Kim. A squalene epoxidase-cholesterolaxis drives colorectal cancer progression and metastatic dissemination [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2769.

Purpose A retrorectal developmental cyst (tailgut cyst, epidermoid cyst, dermoid cyst, teratoma, and duplication) is very rare disease, and the symptoms are not characteristic so that sometimes this disease is still misdiagnosed as a supralevator abscess or a complex anal fistula. We would like to present a clinical approach to this disease. Methods We retrospectively examined the charts of 15 patients who were treated for retrorectal cysts from January 2001 to November 2009. Results All 15 patients were female. The average age was 41 years (range, 21 to 60 years). Fourteen patients (93.3%) were symptomatic, and the most common symptom was anal pain or discomfort. Nine patients (60%) had more than one previous operation (range, 1 to 9 times) for a supralevator abscess, an anal fistula, etc. In 12 patients (80%), the diagnosis could be made by using the medical history and physical examination. Thirteen cysts (80%) were excised completely through the posterior approach. The average diameter of the cysts was 4.8 cm (range, 2 to 10 cm). Pathologic diagnoses were 8 tailgut cysts (53.3%), 5 epidermoid cysts (33.3%) and 2 dermoid cysts (13.3%). The average follow-up period was 18.3 months (range, 1 to 64 months). Conclusion In our experience, high suspicion and physical examination are the most important diagnostic methods. If a female patient has a history of multiple perianal operations, a retrorectal bulging soft mass, a posterior anal dimple, and no conventional creamy foul odorous pus in drainage, the possibility of a retrorectal developmental cyst must be considered.

TRAIL (TNF-related apoptosis inducing ligand) is a promising anti-cancer drug target that selectively induces apoptosis in cancer cells. However, many cancer cells are resistant to TRAIL-induced apoptosis. Therefore, reversing TRAIL resistance is an important step for the development of effective TRAIL-based anti-cancer therapies. We previously reported that knockdown of the TOR signaling pathway regulator-like (TIPRL) protein caused TRAIL-induced apoptosis by activation of the MKK7-c-Jun N-terminal Kinase (JNK) pathway through disruption of the MKK7-TIPRL interaction. Here, we identified Taraxacum officinale F.H. Wigg (TO) as a novel TRAIL sensitizer from a set of 500 natural products using an ELISA system and validated its activity by GST pull-down analysis. Furthermore, combination treatment of Huh7 cells with TRAIL and TO resulted in TRAIL-induced apoptosis mediated through inhibition of the MKK7-TIPRL interaction and subsequent activation of MKK7-JNK phosphorylation. Interestingly, HPLC analysis identified chicoric acid as a major component of the TO extract, and combination treatment with chicoric acid and TRAIL induced TRAIL-induced cell apoptosis via JNK activation due to inhibition of the MKK7-TIPRL interaction. Our results suggest that TO plays an important role in TRAIL-induced apoptosis, and further functional studies are warranted to confirm the importance of TO as a novel TRAIL sensitizer for cancer therapy. © 2015 Wiley Periodicals, Inc.

Malignancy cancer cells are reported to develop mechanisms to resist anoikis (apoptotic cell death from deprivation of cell-cell/matrix interactions), thereby enhancing the survival of cancer cells and secondary tumor formation in distant organs, which is responsible for 90% of cancer-related fatalities. A high serum level of cholesterol (hypercholesterolemia) in patients with colorectal cancers (CRCs) metastasis is reported, but the underlying relationship were never elucidated. Human CRC tissues revealed that the expression of squalene epoxidase (SqE), the rate-limiting enzyme in cholesterol synthesis, is significantly reduced in the advanced stages of CRC. Here we report that the knockdown/degradation of SqE by either the application of small-interfering RNA against SqE or a high-level of cholesterol significantly potentiates CRC cell survival/metastasis via the induction of an epithelial-mesenchymal transition as well as of anoikis resistance. We identified the interactions of SqE with glycogen synthase kinase 3β (GSK3β) and/or p53: SqE knockdown induced the dissociation of GSK3β and p53, thereby resulting in the downregulation of E-cadherin via the inhibition of GSK3 activity and of -catenin degradation, as well as the p53 degradation by the hdm2 upregulation. Overall, the present study demonstrates SqE is a key negative regulator of cancer cell survival and of CRC metastasis. Citation Format: Soo Young Jun, Hyun-Soo Cho, Jeong-Ju Lee, Ji-Yong Yoon, Jun-Ho Ahn, Ju-Sik Min, Sujin Jeon, Jae-Hye Lee, Min Hyuk Choi, Nam-Soon Kim. A novel tumor-suppressor role for squalene epoxidase in human colorectal metastasis. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4130.

When an inflammatory stimulus is given, vascular endothelial cells express various cell adhesion molecules including the vascular cell adhesion molecule (VCAM)-1. In this study, the possibility of specifically delivering anti-inflammatory drugs to activated endothelial cells by utilizing VCAM-1 as a target receptor was explored by loading celecoxib, a selective cyclooxygenase-2 inhibitor, into liposomes coupled to the Fab' fragment against VCAM-1. Anti-VCAM-1-Fab'-conjugated liposomes were prepared by forming an amide linkage between amino groups of Fab' and the carboxylic group of glutaryl-N-phosphatidylethanolamine in liposomes using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide as a cross-linker in the presence of sulpho-N-hydroxysuccinimide. The coupling of Fab' to phospholipids constituting liposomes was confirmed by SDS-PAGE analysis. Under our optimized conjugation conditions, 130.0 µg Fab' was coupled to 1 µmol liposomes. Immunoblotting analysis showed that VCAM-1 protein expression could be induced by incubating human umbilical vein endothelial cells (HUVEC) with TNF-α. Confocal laser microsopy analysis revealed that Fab' conjugation to liposomes selectively increased liposomal uptake in TNF-α-pre-stimulated (VCAM-1-expressed) HUVECs, but not in cells without VCAM-1 expression. The concentration of celecoxib loaded in Fab'-conjugated liposomes was 281.1 ± 29 µg/mL, suggesting that liposomal loading also helped to overcome the limitations in celecoxib administration caused by its poor water solubility. Celecoxib loaded in Fab'-conjugated liposomes inhibited prostaglandin E₂ (PGE₂) production induced by TNF-α-pre-stimulation more efficiently than when loaded in conventional liposomes. Therefore, Fab'-conjugated liposomes served as a drug delivery system with dual functions: targeted delivery and solubilizing capacity.

Purpose of the study: Metastasis or systemic dissemination of cancer cells into secondary organs is responsible for 90% of cancer-related fatalities. Our team previously screened out SL-15 as therapeutic target of gastric cancer through the analysis of gene expression profiling. In this study, we investigated the roles of human SL-15 in colorectal cancer (CRC) metastasis. Experimental procedures: SL-15 levels of metastatic liver CRC tissues and of primary CRC tissues as well as of adjacent nontumour tissues were compared using quantitative RT-PCR. Transwell and wound healing methods were used to determine the migration/invasion abilities of CRC cells. Flow cytometery analysis was performed to measure the apoptotic ratio as well as the levels of E-cadherin/p53/SL-15. Confocal observation and Western blot analysis were used for studying the underlying mechanisms of small interfering RNA against SL-15 (siSL-15)-induced CRC metastasis. Results: The level of SL-15 was higher in the order of metastatic liver CRC tissues, primary CRC tissues and then the adjacent nontumor tissues. siSL-15 significantly induced the migration/invasion of CRC cells that was almost entirely suppressed by the co-expression of SL-15. Importantly, the application of siSL-15 contributes to anoikis resistance of CRC cells via the upregulation of zinc finger E-box-binding homeobox 1 (ZEB1) in stem-like subtype CRC cells and intestinal trefoil factor (ITF) in goblet- like subtype CRC cells by the inhibition of glycogen synthase kinase 3 β (GSK3β) and of β-catenin degradation, thereby leading to downregulation of E-cadherin as well as p53 degradation. Importantly, the interactions among SL-15/p53/GSK3β that were dissociated upon the application of siSL-15 were determined. Conclusions: SL-15 is more highly up-regulated in metastatic liver CRC cancer than in primary CRC cancer and the adjacent nontumor tissue: SL-15 knockdown contributes to anoikis resistance of CRC cells and CRC metastasis via inducing epithelial-to-mesenchymal transition as well as p53 degradation due to the dissociation of SL-15 with GSK3β and p53. Citation Format: Soo Young Jun, Hyun-Soo Cho, Jeong-Ju Lee, Jun-Ho Ahn, Ji-Yong Yoon, Jae-Hye Lee, Min Hyuk Choi, Nam-Soon Kim. Induction of epithelial-to-mesenchymal transition (EMT) by SL-15 knockdown contributes to anoikis resistance in human colorectal cancer metastases. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1446. doi:10.1158/1538-7445.AM2015-1446

Purpose: Although methacholine PC20 helps clinicians to identify asthma, there are practical limitations in using methacholine PC20 to assess asthma control. We assessed the relationship between methacholine PC20 levels and asthma control status in child patients with atopic asthma. Methods: We enrolled 153 children of 8 to 15 years of age with atopic asthma and measured methacholine PC20 of these children when their asthma was controlled. We followed up these patients for more than 2 years with measurements of asthma control score, lung function, bronchodilator response (BDR), and fractional exhaled nitric oxide (FeNO). Results: The geometric mean of methacholine PC20 in the study population was 2.81 mg/mL. Lower methacholine PC20 was found to be associated with lower lung function, higher rate of BDR greater than 12%, higher level of BDR, higher rate of FeNO levels greater than 23 ppb, higher FeNO, higher numbers of asthma aggravation per year, and higher rate of asthma control test scores of 19 or less. Conclusion: These data provide evidences that the degree of methacholine PC20 is linked to disease severity in children with atopic asthma. Thus, regular and close monitoring of asthma control should be required for patients with lower levels of methacholine PC20. (�������� ������ ������ ����(���������������