Cylindromatosis lysine 63 deubiquitinase (CYLD) suppress TLR3-mediated CCL5 expression in human renal proximal tubular epithelial cells.

BACKGROUND: One of the causes of tubulointerstitial nephritis is viral infection, with innate immune responses affecting its pathogenesis. Toll-like receptor 3 (TLR3) recognizes viral infections and acts antivirally by activating signaling to produce inflammatory cytokines/chemokines, including C-C motif chemokine ligand 5 (CCL5) and interferon-ß (IFN-ß). Although cylindromatosis lysine 63 deubiquitinase (CYLD) is known to be associated with tubulointerstitial nephritis and renal function, its role in the antiviral innate immune response in tubular epithelial cells remains unknown. In this study, we investigated the association between CYLD and TLR3-mediated CCL5 production in cultured human renal proximal tubular epithelial cells (hRPTECs). METHODS AND RESULTS: Polyinosinic-polycytidylic acid (poly IC), a synthetic TLR3 ligand, was used to stimulate hRPTECs. mRNA expression was measured using reverse transcription-quantitative polymerase chain reaction. Protein expression was assayed using western blotting or an enzyme-linked immunosorbent assay. Knockdown of IFN-ß, nuclear factor-kappa B (NF-κB) p65, and CYLD was performed by transfecting cells with specific small interfering RNAs. The intracellular localization of CYLD in hRPTECs was analyzed using immunofluorescence. Poly IC induced CCL5 expression in a time- and concentration-dependent manner, and knockdown of either IFN-ß or p65 reduced poly IC-induced CCL5 expression. CYLD knockdown increased the poly IC-induced CCL5, phosphorylated IκB kinase α/ß (IKK complex), and phosphorylated p65 expression. The CYLD protein was localized in the cytoplasm, and poly IC did not alter its expression. CONCLUSION: CYLD may prevent excessive inflammation due to an antiviral innate immune response by suppressing IKK complex and NF-κB activation downstream of TLR3 in hRPTECs.

A computational approach for structural and functional analyses of disease-associated mutations in the human CYLD gene.

Tumor suppressor cylindromatosis protein (CYLD) regulates NF-κB and JNK signaling pathways by cleaving K63-linked poly-ubiquitin chain from its substrate molecules and thus preventing the progression of tumorigenesis and metastasis of the cancer cells. Mutations in CYLD can cause aberrant structure and abnormal functionality leading to tumor formation. In this study, we utilized several computational tools such as PANTHER, PROVEAN, PredictSNP, PolyPhen-2, PhD-SNP, PON-P2, and SIFT to find out deleterious nsSNPs. We also highlighted the damaging impact of those deleterious nsSNPs on the structure and function of the CYLD utilizing ConSurf, I-Mutant, SDM, Phyre2, HOPE, Swiss-PdbViewer, and Mutation 3D. We shortlisted 18 high-risk nsSNPs from a total of 446 nsSNPs recorded in the NCBI database. Based on the conservation profile, stability status, and structural impact analysis, we finalized 13 nsSNPs. Molecular docking analysis and molecular dynamic simulation concluded the study with the findings of two significant nsSNPs (R830K, H827R) which have a remarkable impact on binding affinity, RMSD, RMSF, radius of gyration, and hydrogen bond formation during CYLD-ubiquitin interaction. The principal component analysis compared native and two mutants R830K and H827R of CYLD that signify structural and energy profile fluctuations during molecular dynamic (MD) simulation. Finally, the protein-protein interaction network showed CYLD interacts with 20 proteins involved in several biological pathways that mutations can impair. Considering all these in silico analyses, our study recommended conducting large-scale association studies of nsSNPs of CYLD with cancer as well as designing precise medications against diseases associated with these polymorphisms.

A Misdiagnosed Familiar Brooke-Spiegler Syndrome: Case Report and Review of the Literature.

Aim of the report: Brooke-Spiegler syndrome (BSS) is a rare autosomal dominant disease characterized by the growth of cylindromas, spiradenomas, trichoepitheliomas, or their combination. These neoplasms usually begin in the second decade and progressively increase in number and size over the years. Diagnosis necessitates consideration of family history, clinical examination, histological findings, and genetic analysis. The aim of this paper is to explore the clinical overlap between Brooke-Spiegler syndrome (BSS) and neurofibromatosis type 1 (NF1). We aim to highlight the challenges associated with their differential diagnosis and emphasize the lack of standardized diagnostic criteria and treatment approaches. Case presentation: Hereby, we introduce the case of a 28-year-old male referred for suspicion of neurofibromatosis type 1 (NF1) who initially declined the recommended surgical excision for a scalp mass. After four years, he returned with larger masses of the scalp, and underwent excision of multiple masses, revealing cylindromas, spiradenomas, and spiradenocylindromas. Family history reported similar tumors in his father, who was also diagnosed with NF1 for the presence of multiple subcutaneous lesions on the scalp. Clinical overlap led to a genetic consultation, but testing for CYLD mutations yielded no significant variations. Despite this, the strong family history and consistent findings led to a revised diagnosis of Brooke-Spiegler syndrome, correcting the initial misdiagnosis of NF1 syndrome. Conclusions: Thanks to the evolving landscape of BSS research over the past two decades, its molecular underpinnings, clinical presentation, and histopathological features are now clearer. However, a thorough family history assessment is mandatory when BSS is suspected. It is our belief that a multidisciplinary approach and cooperation between specialists are essential when dealing with BSS. By sharing this case, we hope to underscore the importance of considering BSS as a differential diagnosis, especially in cases with atypical presentations or overlapping features with other syndromes like NF1.

The miR-19a/Cylindromatosis Axis Regulates Pituitary Adenoma Bone Invasion by Promoting Osteoclast Differentiation.

BACKGROUND: The presence of bone invasion in aggressive pituitary adenoma (PA) was found in our previous study, suggesting that PA cells may be involved in the process of osteoclastogenesis. miR-19a (as a key member of the miR-17-92 cluster) has been reported to activate the nuclear factor-кB (NF-кB) pathway and promote inflammation, which could be involved in the process of the bone invasion of pituitary adenoma. METHODS: In this work, FISH was applied to detect miR-19a distribution in tissues from patients with PA. A model of bone invasion in PA was established, GH3 cells were transfected with miR-19a mimic, and the grade of osteoclastosis was detected by HE staining. qPCR was performed to determine the expression of miR-19a throughout the course of RANKL-induced osteoclastogenesis. After transfected with a miR-19a mimic, BMMs were treated with RANKL for the indicated time, and the osteoclast marker genes were detected by qPCR and Western Blot. Pit formation and F-actin ring assay were used to evaluate the function of osteoclast. The TargetScan database and GSEA were used to find the potential downstream of miR-19a, which was verified by Co-IP, Western Blot, and EMSA. RESULTS: Here, we found that miR-19a expression levels were significantly correlated with the bone invasion of PA, both in clinical samples and animal models. The osteoclast formation prior to bone resorption was dramatically enhanced by miR-19, which was mediated by decreased cylindromatosis (CYLD) expression, increasing the K63 ubiquitination of tumor necrosis factor receptor-associated factor 6 (TRAF6). Consequently, miR-19a promotes osteoclastogenesis by the activation of the downstream NF-кB and mitogen-activated protein kinase (MAPK) pathways. CONCLUSIONS: To summarize, the results of this study indicate that PA-derived miR-19a promotes osteoclastogenesis by inhibiting CYLD expression and enhancing the activation of the NF-кB and MAPK pathways.

Clinical significance of cylindromatosis expression in primary hepatocellular carcinoma.

BACKGROUND AND STUDY AIM: There is currently a lack of sensitive biomarkers for the diagnosis of hepatocellular carcinoma (HCC). Low expression of cylindromatosis (CYLD), a tumor suppressor gene that encodes a deubiquitinase, is associated with the development of HCC. The present study, therefore, aimed to determine the clinical utility of measuring CYLD expression in the early diagnosis of HCC. PATIENTS AND METHODS: The present study comprised 257 patients from the Affiliated Hospital of Qingdao University including 90 patients with HCC, 41 patients with liver cirrhosis (LC), 46 patients with hepatitis B (HB), and 80 healthy controls. qPCR was used to measure the amounts of CYLD mRNA in stored blood samples. The sensitivity and specificity of CYLD mRNA in diagnosing HCC was analyzed using receiver operator characteristic (ROC) curves. We also obtained HCC data from the Oncomine database to further verify our results. RESULTS: The relative levels of CYLD mRNA in peripheral blood from patients with HCC (median, 0.060; interquartile range [IQR], 0.019-0.260) was significantly lower than in blood from patients with LC (median, 3.732; IQR, 0.648-14.573), HB (median, 0.419; IQR, 0.255-1.809) and healthy controls (median, 1.262; IQR, 0.279-3.537; P < 0.05). CYLD mRNA levels in peripheral blood were significantly higher in patients with LC compared to healthy controls and patients with HB. Oncomine data demonstrated that CYLD mRNA expression levels in HCC tissues were significantly lower than in normal liver tissues. ROC analysis demonstrated that the combined use of peripheral blood levels of CYLD and AFP had the greatest diagnostic accuracy for HCC (area under the curve (AUC), 0.897; 95 % confidence interval [CI], 0.853-0.942). CYLD had utility as a supplementary marker to AFP for diagnosing HCC. CONCLUSION: Circulating levels of CYLD mRNA are significantly decreased in patients with HCC, indicating CYLD may have utility as a biomarker of HCC. Combined measurement of CYLD mRNA and AFP protein had the greatest diagnostic accuracy.

Potential use of EGFR-targeted molecular therapies for tumor suppressor CYLD-negative and poor prognosis oral squamous cell carcinoma with chemoresistance.

BACKGROUND: Tumor suppressor CYLD dysfunction by loss of its expression, triggers malignant transformation, especially drug resistance and tumor invasion/metastasis. Although loss of CYLD expression is significantly associated with poor prognosis in a large variety of tumors, no clinically-effective treatment for CYLD-negative cancer patients is available. METHODS: We focused on oral squamous cell carcinoma (OSCC), and sought to develop novel therapeutic agents for CYLD-negative cancer patients with poor prognosis. CYLD-knockdown OSCC cells by using CYLD-specific siRNA, were used to elucidate and determine the efficacy of novel drug candidates by evaluating cell viability and epithelial-mesenchymal transition (EMT)-like change. Therapeutic effects of candidate drug on cell line-derived xenograft (CDX) model and usefulness of CYLD as a novel biomarker using patient-derived xenograft (PDX) model were further investigated. RESULTS: CYLD-knockdown OSCC cells were resistant for all currently-available cytotoxic chemotherapeutic agents for OSCC, such as, cisplatin, 5-FU, carboplatin, docetaxel, and paclitaxel. By using comprehensive proteome analysis approach, we identified epidermal growth factor receptor (EGFR), a receptor tyrosine kinase, played key roles in CYLD-knockdown OSCC cells. Indeed, cell survival rate in the cisplatin-resistant CYLD-knockdown OSCC cells was markedly inhibited by treatment with clinically available EGFR tyrosine kinase inhibitors (EGFR-TKIs), such as gefitinib. In addition, gefitinib was significantly effective for not only cell survival, but also EMT-like changes through inhibiting transforming growth factor-ß (TGF-ß) signaling in CYLD-knockdown OSCC cells. Thereby, overall survival of CYLD-knockdown CDX models was significantly prolonged by gefitinib treatment. Moreover, we found that CYLD expression was significantly associated with gefitinib response by using PDX models. CONCLUSIONS: Our results first revealed that EGFR-targeted molecular therapies, such as EGFR-TKIs, could have potential to be novel therapeutic agents for the CYLD-negative OSCC patients with poor prognosis.

SOX4 induces drug resistance of colorectal cancer cells by downregulating CYLD through transcriptional activation of microRNA-17.

Exposure to high doses of anticancer drugs can induce the emergence of a subpopulation of weakly proliferative and drug-tolerant cells. Drug tolerance can reduce the benefits obtained from canonical treatment and reduce the survival rate of patients. Regulation of SRY-related HMG box transcription factor 4 (SOX4) has been proved to affect drug sensitivity. The current study aimed to explore the role of SOX4 in drug resistance of colorectal cancer (CRC) cells as well as the related molecular mechanisms. Expression patterns of SOX4, microRNA-17 (miR-17), and CYLD in both CRC tissues and cells were determined with their relationship analyzed by bioinformatics analysis, dual-luciferase reporter gene assay, and ChIP. Loss- and gain-function assays were performed to ascertain the effect of SOX4, miR-17, and CYLD on biological cellular processes and drug resistance to 5-FU. SOX4 and miR-17 were found to be highly expressed while CYLD was poorly expressed in CRC tissues and cells. Silencing of SOX4 resulted in the suppression of cellular proliferation, invasion, migration as well as a reduction in CRC drug resistance. Mechanically, CYLD was specifically targeted by miR-17, while SOX4 upregulated the expression of miR-17. Functionally, SOX4 triggered drug resistance of CRC cells to 5-FU through the miR-17/CYLD axis. Taken together, the key findings of the present study provides evidence suggesting that SOX4 elevates miR-17 to decrease CYLD, thus inducing chemotherapy resistance of CRC cells.

Exosomal microRNA-588 from M2 polarized macrophages contributes to cisplatin resistance of gastric cancer cells.

BACKGROUND: Gastric cancer is a prevalent malignant cancer with a high incidence and significantly affects the health of modern people globally. Cisplatin (DDP) is one of the most common and effective chemotherapies for patients with gastric cancer, but DDP resistance remains a severe clinical challenge. AIM: To explore the function of M2 polarized macrophages-derived exosomal microRNA (miR)-588 in the modulation of DDP resistance of gastric cancer cells. METHODS: M2 polarized macrophages were isolated and identified by specific markers using flow cytometry analysis. The exosomes from M2 macrophages were identified by transmission electron microscopy and related markers. The uptake of the PKH67-labelled M2 macrophages-derived exosomes was detected in SGC7901 cells. The function and mechanism of exosomal miR-588 from M2 macrophages in the modulation of DDP resistance of gastric cancer cells was analyzed by CCK-8 assay, apoptosis analysis, colony formation assay, Western blot analysis, qPCR analysis, and luciferase reporter assay in SGC7901 and SGC7901/DDP cells, and by tumorigenicity analysis in nude mice. RESULTS: M2 polarized macrophages were isolated from mouse bone marrow stimulated with interleukin (IL)-13 and IL-4. Co-cultivation of gastric cancer cells with M2 polarized macrophages promoted DDP resistance. M2 polarized macrophages-derived exosomes could transfer in gastric cancer cells to enhance DDP resistance. Exosomal miR-588 from M2 macrophages contributed to DDP resistance of gastric cancer cells. miR-588 promoted DDP-resistant gastric cancer cell growth in vivo. miR-588 was able to target cylindromatosis (CYLD) in gastric cancer cells. The depletion of CYLD reversed miR-588 inhibition-regulated cell proliferation and apoptosis of gastric cancer cells exposed to DDP. CONCLUSION: In conclusion, we uncovered that exosomal miR-588 from M2 macrophages contributes to DDP resistance of gastric cancer cells by partly targeting CYLD. miR-588 may be applied as a potential therapeutic target for the treatment of gastric cancer.

Deficiency of the CYLD Impairs Fear Memory of Mice and Disrupts Neuronal Activity and Synaptic Transmission in the Basolateral Amygdala.

Fear learning and memory are crucial for animal survival. Abnormal fear memory is a hallmark of many neuropsychiatric disorders. Appropriate neuronal activation and excitability in the basolateral amygdala (BLA) are necessary for the formation of fear memory. The gene cylindromatosis (Cyld), which encodes a lysine-63 deubiquitinase, is expressed in several brain regions including the amygdala. The functions of the cylindromatosis protein (CYLD) in the regulation of the neuronal activity, neural circuits and fear memory, remain largely unknown, however. Here, we report that Cyld knockout impairs amygdala-dependent tone-cued fear memory. The number of c-Fos+ neurons responding to the tone-cued fear test was reduced in the BLA of Cyld -/- mice, suggesting that the absence of CYLD causes aberrant neuronal activation. We found that this aberrant neuronal activation in the BLA of Cyld -/- mice may relate to the decreased excitability of principal neurons. Another possibility of aberrant neuronal activation could be the impaired excitatory synaptic transmission in the BLA of Cyld -/- mice. Specifically, both the frequency of spontaneous excitatory postsynaptic currents and the amplitude of miniature excitatory postsynaptic currents in BLA principal neurons were decreased. In addition, Cyld mutation caused an increase in both the frequency of miniature inhibitory postsynaptic currents in principal neurons and the number of parvalbumin+ interneurons, consistent with excessive local circuit inhibition in the BLA of Cyld -/- mice. Taken together, these results suggest that CYLD deficiency disrupts the neuronal activity and synaptic transmission in the BLA of mice which may contribute to the impaired fear memory observed in Cyld -/- mice.

Turban Tumor Syndrome: In Search of a Gold Standard - A Case Report.

Turban tumor syndrome (TTS) is a rare condition characterized by predisposition to developing multiple adnexal tumors. It is the rare autosomal dominant genodermatosis that is associated with the mutation of the CYLD suppressor gene. We herein report rare TTS in an adult who suffered from numerous episodic ulcerations of the scalp tumors and frequent bleeding following a minor trauma. The plain radiograms of the skull excluded bone marrow infiltration, and no regional lymphadenopathy was noted. The patient underwent total scalp excision and split skin grafting under general anesthesia in a single-stage operation. Recovery was uneventful. No recurrence was observed during the 2-year follow-up. Due to a high recurrence rate and risk of neoplastic transformation, surgery should be considered as the gold standard.

Potential role for the tumor suppressor CYLD in brain and notochord development.

BACKGROUND: The cylindromatosis (CYLD) tumor suppressor is a microtubule-associated deubiquitinase that plays a critical role in the regulation of cell signaling and contributes to a variety of physiological and pathological processes. However, the functions of CYLD in zebrafish are less well known, particularly with regard to their development and physiology. In this context, we investigated the loss of function of CYLD in zebrafish via transcription activator-like effector nuclease (TALEN)-based gene deletion. METHODS: Semi-quantitative RT-PCR was used to quantify CYLD mRNA expression in zebrafish embryos at various developmental stages. We also performed whole-mount in situ hybridization to further assess the dynamic expression and distribution of CYLD in the entire zebrafish embryos at different stages. In addition, we deleted CYLD in zebrafish with TALENs to investigate its potential impact on embryonic development. RESULTS: The expression of CYLD mRNA varied during early embryonic development. The CYLD mRNA localized to the brain and notochord of developing zebrafish embryos. Homozygous deletion of CYLD resulted in embryonic death before 8 h post-fertilization. CONCLUSIONS: CYLD appears to play an important role in central nervous system development in zebrafish. Although severe embryonic death restricted analysis of homozygous mutants, further research into the role of CYLD in central nervous system development is warranted.

Down-regulation of cylindromatosis protein phosphorylation by BTK inhibitor promotes apoptosis of non-GCB-diffuse large B-cell lymphoma.

BACKGROUND: Non-germinal center B-cell-like diffuse large B-cell lymphoma (non-GCB-DLBCL) has worse clinical outcome than GCB-DLBCL, and some relapsed/refractory non-GCB-DLBCL (R/R non-GCB-DLBCL) are even resistant to CD20 monoclonal antibody (rituximab). Bruton's tyrosine kinase inhibitors (BTKis) are new drugs for B-cell lymphoma. BTKis can promote apoptosis of DLBCL by inactivating nuclear transcription factor κB (NFκB) signaling pathway. Cylindromatosis (CYLD) is a tumor suppressor and ubiquitinase. CYLD can inactivate NFκB signaling pathway through ubiquitination and regulate the apoptosis of hematological tumors. The ubiquitination of CYLD can be regulated by phosphorylation, suggesting that the regulation of CYLD phosphorylation can be a potential mechanism to promote the apoptosis of hematological tumors. Therefore, we hypothesized that BTKis could promote the apoptosis of non-GCB-DLBCL by regulating the phosphorylation of CYLD, especially in rituximab resistant cases, and we proved this hypothesis through both in vivo and in vitro experiments. METHODS: The baseline expression levels of CYLD phosphorylation in non-GCB-DLBCL patients and cell lines were detected by Western Blotting. The non-GCB-DLBCL cell lines were treated with BTKis, and apoptosis induced by BTKis treatment was detected by Western blotting, cell viability assay and Annexin V assay. To verify whether the effect of BTKis on apoptosis in non-GCN-DLBCL cells is CYLD dependent, the expression of CYLD was knocked down by lentiviral shRNAs. To verify the effect of BTKis on the phosphorylation of CYLD and the apoptosis in vivo and in rituximab resistant non-GCB-DLBCL, the xeograft model and rituximab resistant non-GCB-DLBCL cells were generated by tumor cell inoculation and escalation of drug concentrations, respectively. RESULTS: BTKis induced apoptosis by down-regulating CYLD phosphorylationin in non GCB-DLBCL, xenograft mouse model, and rituximab-resistant cells, and this effect could be enhanced by rituximab. Knocking-down CYLD reversed apoptosis which was induced by BTKis. BTKis induced CYLD-dependent apoptosis in non-GCB-DLBCL including in rituximab-resistant cells. CONCLUSIONS: The present results indicated that CYLD phosphorylation is a potential clinical therapeutic target for non-GCB-DLBCL, especially for rituximab-resistant relapsed/refractory cases.

CYLD mediates human pulmonary artery smooth muscle cell dysfunction in congenital heart disease-associated pulmonary arterial hypertension.

Pulmonary arterial hypertension (PAH) is a common complication of congenital heart disease (CHD). Deubiquitinase cylindromatosis (CYLD) has been reported to significantly aggravate vascular smooth muscle cell (VSMC) phenotypic transformation, proliferation, and migration. Here, we aimed to further investigate its roles and underlying mechanisms in the CHD-PAH development. The expression of CYLD in the lung tissues from CHD-PAH patients and monocrotaline (MCT) plus aortocaval (AV)-induced PAH rats, pulmonary artery smooth muscle cells (PASMCs) from MCT-AV-induced PAH rats, and human PASMCs (HPASMCs) was evaluated. After infection with CYLD siRNA or pcNDA3.1-CYLD, the proliferation, migration, and apoptosis of HPASMCs were measured using an EdU assay, transwell and scratch wound healing assays, and flow cytometric assay, respectively. An adeno-associated virus (AAV) vector encoding CYLD was used to suppress CYLD expression by being intratracheally instilled in rats 7 days before MCT-AV treatment. The results showed that CYLD was increased in the lung tissues from CHD-PAH patients and MCT-AV-induced PAH rats, and in PASMCs from MCT-AV-induced PAH rats. The contractile-type HPASMCs expressed low levels of CYLD, while the proliferative synthetic-type HPASMCs expressed high levels of CYLD. In addition, CYLD could mediate HPASMC dysfunction, which regulated HPASMC phenotypic transformation and proliferation via the modulation of p38 and ERK activation, while CYLD regulated HPASMC migration via the modulation of p38 activation. In vivo results demonstrated that the local suppression of CYLD expression could attenuate the increased levels of PAH and its associated pulmonary vascular remodeling in MCT-AV-induced PAH rats. Collectively, these results indicated that CYLD might be a potential novel therapeutic target for the prevention of PAH and pulmonary vascular remodeling in CHD-PAH through the modulation of HPASMC dysfunction.

Cylindromatosis Lysine 63 Deubiquitinase (CYLD) Regulates NF-kB Signaling Pathway and Modulates Fibroblast and Endothelial Cells Recruitment in Nasopharyngeal Carcinoma.

Nasopharyngeal carcinoma (NPC) is a malignant epithelial carcinoma of the nasopharynx. Cylindromatosis lysine 63 deubiquitinase (CYLD), a NF-kB inhibitor, was reported as one of the top mutated candidate genes in NPC. NF-kB is an inducible transcription factor, contributing to cancer via regulating inflammation, angiogenesis, cell proliferation, and metastasis. In this study, the impact of CYLD on regulating the NF-kB signaling pathway and its contribution to NPC development was studied using in vitro and in vivo functional assays, together with single cell RNA sequencing to understand the NPC tumor microenvironment. CYLD was downregulated in NPC clinical specimens and multiple cell lines. Functional assays revealed CYLD inhibits NPC cell proliferation and migration in vitro and suppresses NPC tumorigenicity and metastasis in vivo by negatively regulating the NF-kB signaling pathway. Additionally, CYLD was able to inhibit fibroblast and endothelial stromal cell infiltration into the NPC tumor microenvironment. These findings suggest that CYLD inhibits NPC development and provides strong evidence supporting a role for CYLD inhibiting fibroblast and endothelial stromal cell infiltration into NPC via suppressing the NF-kB pathway.

miR-454 promotes survival and induces oxaliplatin resistance in gastric carcinoma cells by targeting CYLD.

MicroRNA-454 (miR-454), is involved in the progression of various types of cancers. The present study aimed to evaluate the effect of miR-454 on the progression of gastric cancer. SGC-7901 cells overexpressing or silencing miR454 were constructed via transfection and the survival rate of the cells was determined. The relationship between miR-454 and cylindromatosis (CYLD) was explored and the influence of miR-454 on oxaliplatin resistance was investigated in SGC-7901 cells. It was determined that overexpression of miR-454 increased the number of colonies and reduced apoptosis rate of SGC-7901 cells. The CYLD gene was identified as a direct target of miR-454. miR-454 overexpression downregulated the expression of CYLD, leading to an increase in SGC-7901 cell proliferation. Finally, miR-454 was also demonstrated to induce resistance to oxaliplatin in gastric cancer cells. In conclusion, the present in vitro findings suggested that miR-454 might be a novel therapeutic target for gastric cancer.

Loss of Tumor Suppressor CYLD Expression Triggers Cisplatin Resistance in Oral Squamous Cell Carcinoma.

Cisplatin is one of the most effective chemotherapeutic agents commonly used for several malignancies including oral squamous cell carcinoma (OSCC). Although cisplatin resistance is a major obstacle to effective treatment and is associated with poor prognosis of OSCC patients, the molecular mechanisms by which it develops are largely unknown. Cylindromatosis (CYLD), a deubiquitinating enzyme, acts as a tumor suppressor in several malignancies. Our previous studies have shown that loss of CYLD expression in OSCC tissues is significantly associated with poor prognosis of OSCC patients. Here, we focused on CYLD expression in OSCC cells and determined whether loss of CYLD expression is involved in cisplatin resistance in OSCC and elucidated its molecular mechanism. In this study, to assess the effect of CYLD down-regulation on cisplatin resistance in human OSCC cell lines (SAS), we knocked-down the CYLD expression by using CYLD-specific siRNA. In cisplatin treatment, cell survival rates in CYLD knockdown SAS cells were significantly increased, indicating that CYLD down-regulation caused cisplatin resistance to SAS cells. Our results suggested that cisplatin resistance caused by CYLD down-regulation was associated with the mechanism through which both the reduction of intracellular cisplatin accumulation and the suppression of cisplatin-induced apoptosis via the NF-κB hyperactivation. Moreover, the combination of cisplatin and bortezomib treatment exhibited significant anti-tumor effects on cisplatin resistance caused by CYLD down-regulation in SAS cells. These findings suggest the possibility that loss of CYLD expression may cause cisplatin resistance in OSCC patients through NF-κB hyperactivation and may be associated with poor prognosis in OSCC patients.

[Cylindromas-rare but striking]. / Zylindrome ­ selten aber eindrucksvoll.

Cylindromas are rare tumors of adnexal structures in adults. They are predominantly found on the scalp and face. More impressive than incidentally diagnosed solitary cylindromas are multiple tumors in patients with familial Brooke-Spiegler syndrome. If many large cylindromas appear on the head, they are termed turban tumor. Sudden growth or ulceration should raise suspicion for malignant transformation.

[Research progress of deubiquitinating enzyme CYLD to regulate liver-related diseases].

Cylindromatosis gene is a kind of tumor suppressor genes, whose mutation or deletion will lead to the development of a cylindrical tumor. The deubiquitinating enzyme CYLD protein encoded by it is a member of the deubiquitinating enzyme family. CYLD alters the function of the target molecules by removing the ubiquitin chain linked to the substrate protein K63, and participates in the regulation of signaling pathways, such as NF-κB, JNK and Wnt. This article reviews the recent year's research progress of CYLD, especially its negative regulatory role in the progression of liver-related diseases.

[Free latissimus dorsi flap lacing and local care in two-stage scalp reconstruction]. / Laçage de lambeau libre de grand dorsal dans le cadre des soins locaux d'un lambeau en nourrice du cuir chevelu.

Surgical treatment of large and multiple lesions of irradiated scalp may require subtotal scalp exeresis and reconstruction in two-stage free flap surgery: harvesting and placing the flap first, then scalp removing and defect covering in a second step. This strategy raises the question of how to care the flap between the two surgeries. We report an original technique of free latissimus dorsi flap lacing. A 70-year-old male, afflicted with familial cylindromatosis and treated by brachytherapy 18years ago, received a free latissimus dorsi myocutaneous flap in two-stage surgery, allowing 25×25cm pathological scalp exeresis. During first step, suture clips were fixed in two rows around the future scalp defect, in order to be used as anchors for the flap lacing. Braided wire were chosen for a better steerability, and to prevent knots untightening. Thus, the flap were placed in "anatomical" place, next to the scalp, pending secondary procedure. This situation permitted to avoid flap or pedicle compression or plication, and to ease flap care. The wires were tighten as shoelaces, allowing them to be undone and done as desired. The two-stage free latissimus dorsi flap reconstruction of scalp large defect permitted us to assess the flap reliability before final reconstruction. The lacing solution allowed us regular local care and convenient flap handling, while favoriting its optimal placing next to its future location.

CYLD deficiency promotes pancreatic cancer development by causing mitotic defects.

Successful treatment of pancreatic cancer, which has the highest mortality rate among all types of malignancies, has challenged oncologists for decades, and early detection would undoubtedly increase favorable patient outcomes. The identification of proteins involved in pancreatic cancer progression could lead to biomarkers for early detection of this disease. This study identifies one potential candidate, cylindromatosis (CYLD), a deubiquitinase and microtubule-binding protein that plays a suppressive role in pancreatic cancer development. In pancreatic cancer samples, downregulation of CYLD expression resulted from a loss in the copy number of the CYLD gene; additionally, reduced expression of CYLD negatively correlated with the clinicopathological parameters. Further study demonstrated that CYLD deficiency promoted colony formation in vitro and pancreatic cancer growth in vivo. Mechanistic studies revealed that CYLD is essential for spindle orientation and properly oriented cell division; CYLD deficiency resulted in a substantial increase in chromosome missegregation. Taken together, these data indicate a critical role for CYLD in suppressing pancreatic tumorigenesis, implicating its potential as a biomarker for early detection of pancreatic cancer and a prognostic indicator of patient outcomes.