RESUMO
Cytosolic sulfotransferases (SULTs) are cytosolic enzymes that catalyze the transfer of sulfonate group to key endogenous compounds, altering the physiological functions of their substrates. SULT enzymes catalyze the O-sulfonation of hydroxy groups or N-sulfonation of amino groups of substrate compounds. In this study, we report the discovery of C-sulfonation of α,ß-unsaturated carbonyl groups mediated by a new SULT enzyme, SULT7A1, and human SULT1C4. Enzymatic assays revealed that SULT7A1 is capable of transferring the sulfonate group from 3'-phosphoadenosine 5'-phosphosulfate to the α-carbon of α,ß-unsaturated carbonyl-containing compounds, including cyclopentenone prostaglandins as representative endogenous substrates. Structural analyses of SULT7A1 suggest that the C-sulfonation reaction is catalyzed by a novel mechanism mediated by His and Cys residues in the active site. Ligand-activity assays demonstrated that sulfonated 15-deoxy prostaglandin J2 exhibits antagonist activity against the prostaglandin receptor EP2 and the prostacyclin receptor IP. Modification of α,ß-unsaturated carbonyl groups via the new prostaglandin-sulfonating enzyme, SULT7A1, may regulate the physiological function of prostaglandins in the gut. Discovery of C-sulfonation of α,ß-unsaturated carbonyl groups will broaden the spectrum of potential substrates and physiological functions of SULTs.
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Immunotherapy has attracted considerable attention as a therapeutic strategy for cancers including acute myeloid leukemia (AML). In this study, we found that the development of several aggressive subtypes of AML is slower in Rag2-/- mice despite the lack of B and T lymphocytes, even compared to the immunologically normal C57BL/6 mice. Furthermore, an orally active p53-activating drug shows stronger antileukemia effect on AML in Rag2-/- mice than C57BL/6 mice. Intriguingly, Natural Killer (NK) cells in Rag2-/- mice are increased in number, highly express activation markers, and show increased cytotoxicity to leukemia cells in a coculture assay. B2m depletion that triggers missing-self recognition of NK cells impairs the growth of AML cells in vivo. In contrast, NK cell depletion accelerates AML progression in Rag2-/- mice. Interestingly, immunogenicity of AML keeps changing during tumor evolution, showing a trend that the aggressive AMLs generate through serial transplantations are susceptible to NK cell-mediated tumor suppression in Rag2-/- mice. Thus, we show the critical role of NK cells in suppressing the development of certain subtypes of AML using Rag2-/- mice, which lack functional lymphocytes but have hyperactive NK cells.
Assuntos
Células Matadoras Naturais , Leucemia Mieloide Aguda , Animais , Camundongos , Camundongos Knockout , Camundongos Endogâmicos C57BL , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Linfócitos T , Proteínas de Ligação a DNA/genéticaRESUMO
Malignant peripheral nerve sheath tumors (MPNSTs) arising from the trigeminal nerves are extremely rare (only 45 cases, including the present case, have been published) and have been reported to develop de novo from the peripheral nerve sheath and are not transformed from a schwannoma or neurofibroma. Here, we report a case of MPNSTs of the trigeminal nerve caused by the malignant transformation of a trigeminal schwannoma, with a particular focus on genetic considerations. After undergoing a near-total resection of a histologically typical benign schwannoma, the patient presented with regrowth of the tumor 10 years after the primary excision. Histopathologic and immunochemical examinations confirmed the recurrent tumor to be an MPNST. Comprehensive genomic analyses (FoundationOne panel-based gene assay) showed that only the recurrent MPNST sample, not the initial diagnosis of schwannoma, harbored genetic mutations, including NF1-p.R2637* and TP53-p.Y234H, candidate gene mutations associated with malignant transformation. Moreover, the results of reverse transcription polymerase chain reaction showed that the fusion of SH3PXD2A and HTRA1, which has been reported as one of the responsible genetic aberrations of schwannoma, was detected in the recurrent tumor. Taken together, we could illustrate the accumulation process of gene abnormalities for developing MPNSTs from normal cells via schwannomas.
Assuntos
Neoplasias de Bainha Neural , Neurilemoma , Neurofibrossarcoma , Humanos , Neoplasias de Bainha Neural/genética , Neurofibrossarcoma/complicações , Neurilemoma/genética , Neurilemoma/complicações , Neurilemoma/patologia , Transformação Celular Neoplásica/genética , MutaçãoRESUMO
Transcription factor RUNX1 plays important roles in hematopoiesis and leukemogenesis. RUNX1 function is tightly controlled through posttranslational modifications, including ubiquitination and acetylation. However, its regulation via ubiquitination, especially proteasome-independent ubiquitination, is poorly understood. We previously identified DTX2 as a RUNX1-interacting E3 ligase using a cell-free AlphaScreen assay. In this study, we examined whether DTX2 is involved in the regulation of RUNX1 using in vitro and ex vivo analyses. DTX2 bound to RUNX1 and other RUNX family members RUNX2 and RUNX3 through their C-terminal region. DTX2-induced RUNX1 ubiquitination did not result in RUNX1 protein degradation. Instead, we found that the acetylation of RUNX1, which is known to enhance the transcriptional activity of RUNX1, was inhibited in the presence of DTX2. Concomitantly, DTX2 reduced the RUNX1-induced activation of an MCSFR luciferase reporter. We also found that DTX2 induced RUNX1 cytoplasmic mislocalization. Moreover, DTX2 overexpression showed a substantial growth-inhibitory effect in RUNX1-dependent leukemia cell lines. Thus, our findings indicate a novel aspect of the ubiquitination and acetylation of RUNX1 that is modulated by DTX2 in a proteosome-independent manner.
Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core , Leucemia , Humanos , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Regulação da Expressão Gênica , Leucemia/genéticaRESUMO
Adrenomedullin (AM) is a peptide with pleiotropic physiological functions that attenuates intestinal mucosal inflammation. However, the mechanism underpinning mucosal protection by AM is not fully understood, and its effect on intestinal epithelial cells remains unclear. Here, we investigated the effects of AM on junctional molecules in primary-cultured murine intestinal epithelial cells and discovered that AM upregulates claudin-4 expression. In a mouse model of dextran sulfate sodium-induced colitis, AM administration also enhanced claudin-4 expression and accelerated mucosal regeneration. Furthermore, AM reversed TNFα-mediated downregulation of claudin-4 and loss of cell-cell adhesion of the HCT116 human intestinal epithelial cell line in vitro. These results indicate that AM may enhance intestinal epithelial integrity by upregulating claudin-4 expression.
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Adrenomedulina , Colite , Camundongos , Humanos , Animais , Adrenomedulina/efeitos adversos , Adrenomedulina/metabolismo , Claudina-4 , Colite/induzido quimicamente , Epitélio/metabolismoRESUMO
MET is a high-affinity receptor tyrosine kinase of HGF (hepatocyte growth factor). HGF is secreted as an inactive single-chain precursor (pro-HGF), which requires proteolytic activation for conversion to an active form. HGF activator inhibitor (HAI)-2 is a transmembrane Kunitz-type serine protease inhibitor, which inhibits all pro-HGF-activating enzymes. In RCC, increased expression of MET and decreased expression of HAI-2 were reported to be poor prognostic factors. In the current study, we tried to inhibit the growth of RCC cells by dual inhibition of both MET phosphorylation and pro-HGF-activation using MET inhibitor and HAI-2 overexpression. A transgenic mouse model which expressed human HGF (HGF mouse) was used for in vivo analysis to evaluate the HGF/MET signaling axis accurately. Initially, doxycycline-induced HAI-2 overexpression RCC cells (786-O-HAI2) were prepared. The cells were cultured with pro-HGF, and inhibitory effect of MET inhibitor (SCC244) and HAI-2 was evaluated by phosphorylation of MET and cell proliferation. Next, the cells were subcutaneously implanted to HGF mice and the growth inhibition was determined by SCC244 and HAI-2. Single use of each inhibitor showed significant inhibition in MET phosphorylation, migration and proliferation of 786-O-HAI2 cells; however, the strongest effect was observed by combined use of both inhibitors. Although in vivo analysis also showed apparent downregulation of MET phosphorylation and growth inhibition in combined treatment, statistical significance was not observed compared with single use of MET inhibitor. Combined treatment with MET-TKI and HAI-2 suggested to consider as a candidate for new strong therapy for RCC.
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Carcinoma de Células Renais , Neoplasias Renais , Humanos , Animais , Camundongos , Fator de Crescimento de Hepatócito/metabolismo , Camundongos SCID , Glicoproteínas de Membrana/metabolismo , Serina Endopeptidases/metabolismo , Inibidor da Tripsina de Soja de Kunitz/metabolismo , Proteínas Secretadas Inibidoras de Proteinases/metabolismo , Proteínas Proto-Oncogênicas c-met/metabolismoRESUMO
Inosine monophosphate dehydrogenase (IMPDH) is a rate-limiting enzyme in de novo guanine nucleotide synthesis pathway. Although IMPDH inhibitors are widely used as effective immunosuppressants, their antitumor effects have not been proven in the clinical setting. Here, we found that acute myeloid leukemias (AMLs) with MLL-fusions are susceptible to IMPDH inhibitors in vitro. We also showed that alternate-day administration of IMPDH inhibitors suppressed the development of MLL-AF9-driven AML in vivo without having a devastating effect on immune function. Mechanistically, IMPDH inhibition induced overactivation of Toll-like receptor (TLR)-TRAF6-NF-κB signaling and upregulation of an adhesion molecule VCAM1, which contribute to the antileukemia effect of IMPDH inhibitors. Consequently, combined treatment with IMPDH inhibitors and the TLR1/2 agonist effectively inhibited the development of MLL-fusion AML. These findings provide a rational basis for clinical testing of IMPDH inhibitors against MLL-fusion AMLs and potentially other aggressive tumors with active TLR signaling.
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Leucemia Mieloide Aguda , Proteína de Leucina Linfoide-Mieloide , Humanos , Proteína de Leucina Linfoide-Mieloide/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Inibidores Enzimáticos/farmacologia , NF-kappa B , Imunossupressores/uso terapêuticoRESUMO
Recent studies have demonstrated that epigenetic modifications are deeply involved in neurogenesis; however, the precise mechanisms remain largely unknown. To determine the role of UTX (also known as KDM6A), a demethylase of histone H3K27, in neural development, we generated Utx-deficient mice in neural stem/progenitor cells (NSPCs). Since Utx is an X chromosome-specific gene, the genotypes are sex-dependent; female mice lose both Utx alleles (UtxΔ/Δ ), and male mice lose one Utx allele yet retain one Uty allele, the counterpart of Utx on the Y chromosome (UtxΔ/Uty ). We found that UtxΔ/Δ mice exhibited fetal ventriculomegaly and died soon after birth. Immunofluorescence staining and EdU labeling revealed a significant increase in NSPCs and a significant decrease in intermediate-progenitor and differentiated neural cells. Molecular analyses revealed the downregulation of pathways related to DNA replication and increased H3K27me3 levels around the transcription start sites in UtxΔ/Δ NSPCs. These results indicate that UTX globally regulates the expression of genes required for proper neural development in NSPCs, and UTX deficiency leads to impaired cell cycle exit, reduced differentiation, and neonatal death. Interestingly, although UtxΔ/Uty mice survived the postnatal period, most died of hydrocephalus, a clinical feature of Kabuki syndrome, a congenital anomaly involving UTX mutations. Our findings provide novel insights into the role of histone modifiers in neural development and suggest that UtxΔ/Uty mice are a potential disease model for Kabuki syndrome.
Assuntos
Histonas , Hidrocefalia , Animais , Feminino , Masculino , Camundongos , Desenvolvimento Fetal , Histona Desmetilases/genética , Hidrocefalia/genética , Neurogênese , Células-Tronco , Células-Tronco NeuraisRESUMO
BACKGROUND: Dura-attached supratentorial extra-axial ependymoma is a very rare type of tumor, with only nine reported cases. Preoperative diagnosis of dura-attached supratentorial extra-axial ependymoma is difficult and often radiologically misdiagnosed as a meningioma. We report a case of dura-attached supratentorial extra-axial ependymoma that was misdiagnosed using intraoperative histological and cytological examinations. CASE PRESENTATION: A 26-year-old Japanese man with headache and nausea was referred to our medical facility. Magnetic resonance imaging revealed a cystic mass of 70 × 53 × 57 mm in the left temporoparietal lobe. A peritumoral band with hyperintensity on T2-weighted imaging was observed at the periphery of the lesion, suggesting an extra-axial lesion with no apparent connection to the ventricle. A dural tail sign was also noted on the gadolinium-enhanced T1-weighted image. Preoperative clinical diagnosis was meningioma. Proliferated tumor cells in sheets with intermingled branching vessels were observed in the frozen tissue. Perivascular rosettes were inconspicuous, and the tumor cells had rhabdoid cytoplasm. The tumor was intraoperatively diagnosed as a meningioma, suspected to be a rhabdoid meningioma. Perivascular rosettes were evident in the formalin-fixed paraffin-embedded tissues, suggesting ependymoma. The tumor cells had eosinophilic cytoplasm without a rhabdoid appearance. Anaplastic features, such as high tumor cellularity, increased mitotic activity, microvascular proliferation, and necrosis, were observed. Ependymal differentiation was confirmed on the basis of ultrastructural analysis. Molecular analysis detected C11orf95-RELA fusion gene. The final diagnosis was RELA fusion-positive ependymoma, World Health Organization grade III. CONCLUSION: Owing to its unusual location, dura-attached supratentorial extra-axial ependymomas are frequently misdiagnosed as meningiomas. Neuropathologists should take great precaution in intraoperatively diagnosing this rare subtype of ependymoma to avoid misdiagnosis of the lesion as other common dura-attached tumors.
Assuntos
Ependimoma , Neoplasias Meníngeas , Meningioma , Neoplasias Supratentoriais , Adulto , Erros de Diagnóstico , Ependimoma/diagnóstico , Ependimoma/patologia , Ependimoma/cirurgia , Humanos , Masculino , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/cirurgia , Meningioma/diagnóstico , Meningioma/cirurgia , Neoplasias Supratentoriais/diagnóstico , Neoplasias Supratentoriais/patologia , Neoplasias Supratentoriais/cirurgia , Fator de Transcrição RelA/genéticaRESUMO
Myelodysplastic syndrome (MDS) is a clonal disorder of hematopoietic stem cells (HSCs), characterized by ineffective hematopoiesis and frequent progression to leukemia. It has long remained unresolved how MDS cells, which are less proliferative, inhibit normal hematopoiesis and eventually dominate the bone marrow space. Despite several studies implicating mesenchymal stromal or stem cells (MSCs), a principal component of the HSC niche, in the inhibition of normal hematopoiesis, the molecular mechanisms underlying this process remain unclear. Here, we demonstrate that both human and mouse MDS cells perturb bone metabolism by suppressing the osteolineage differentiation of MSCs, which impairs the ability of MSCs to support normal HSCs. Enforced MSC differentiation rescues the suppressed normal hematopoiesis in both in vivo and in vitro MDS models. Intriguingly, the suppression effect is reversible and mediated by extracellular vesicles (EVs) derived from MDS cells. These findings shed light on the novel MDS EV-MSC axis in ineffective hematopoiesis.
Assuntos
Vesículas Extracelulares , Células-Tronco Mesenquimais , Síndromes Mielodisplásicas , Animais , Vesículas Extracelulares/metabolismo , Hematopoese , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Síndromes Mielodisplásicas/metabolismoRESUMO
After the new molecular-based classification was reported to be useful for predicting prognosis, the T2-fluid-attenuated inversion recovery (FLAIR) mismatch sign has gained interest as one of the promising methods for detecting lower grade gliomas (LGGs) with isocitrate dehydrogenase (IDH) mutations and chromosome 1p/19q non-codeletion (IDH mut-Noncodel) with high specificity. Although all institutions could use T2-FLAIR mismatch sign without any obstacles, this sign was not completely helpful because of its low sensitivity. In this study, we attempted to uncover the mechanism of T2-FLAIR mismatch sign for clarifying the cause of this sign's low sensitivity. Among 99 patients with LGGs, 22 were T2-FLAIR mismatch sign-positive (22%), and this sign as a marker of IDH mut-Noncodel showed a sensitivity of 55.6% and specificity of 96.8%. Via pathological analyses, we could provide evidence that not only microcystic changes but the enlarged intercellular space was associated with T2-FLAIR mismatch sign (p = 0.017). As per the molecular analyses, overexpression of mTOR-related genes (m-TOR, RICTOR) were detected as the molecular events correlated with T2-FLAIR mismatch sign (p = 0.020, 0.030. respectively). Taken together, we suggested that T2-FLAIR mismatch sign could pick up the IDH mut-Noncodel LGGs with enlarged intercellular space or that with overexpression of mTOR-related genes.
Assuntos
Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Glioma/genética , Glioma/patologia , Humanos , Isocitrato Desidrogenase/genética , Imageamento por Ressonância Magnética/métodos , Mutação , Estudos Retrospectivos , Serina-Treonina Quinases TOR/genéticaRESUMO
Hepatocyte growth factor (HGF) activator inhibitor type-1 (HAI-1), encoded by the SPINT1 gene, is a transmembrane protease inhibitor that regulates membrane-anchored serine proteases, particularly matriptase. Here, we explored the role of HAI-1 in tongue squamous cell carcinoma (TSCC) cells. An immunohistochemical study of HAI-1 in surgically resected TSCC revealed the cell surface immunoreactivity of HAI-1 in the main portion of the tumor. The immunoreactivity decreased in the infiltrative front, and this decrease correlated with enhanced lymphatic invasion as judged by podoplanin immunostaining. In vitro homozygous deletion of SPINT1 (HAI-1KO) in TSCC cell lines (HSC3 and SAS) suppressed the cell growth rate but significantly enhanced invasion in vitro. The loss of HAI-1 resulted in enhanced pericellular activities of proteases, such as matriptase and urokinase-type plasminogen activator, which induced activation of HGF/MET signaling in the co-culture with pro-HGF-expressing fibroblasts and plasminogen-dependent plasmin generation, respectively. The enhanced plasminogen-dependent plasmin generation was abrogated partly by matriptase silencing. Culture supernatants of HAI-1KO cells had enhanced potency for converting the proform of vascular endothelial growth factor-C (VEGF-C), a lymphangiogenesis factor, into the mature form in a plasminogen-dependent manner. Furthermore, HGF significantly stimulated VEGF-C expression in TSCC cells. Orthotopic xenotransplantation into nude mouse tongue revealed enhanced lymphatic invasion of HAI-1KO TSCC cells compared to control cells. Our results suggest that HAI-1 insufficiency leads to dysregulated pericellular protease activity, which eventually orchestrates robust activation of protease-dependent growth factors, such as HGF and VEGF-C, in a tumor microenvironment to contribute to TSCC progression.
Assuntos
Carcinoma de Células Escamosas , Proteínas Secretadas Inibidoras de Proteinases , Neoplasias da Língua , Animais , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Fibrinolisina/genética , Homozigoto , Humanos , Camundongos , Plasminogênio/genética , Proteínas Secretadas Inibidoras de Proteinases/genética , Proteínas Secretadas Inibidoras de Proteinases/metabolismo , Deleção de Sequência , Serina Endopeptidases , Neoplasias da Língua/genética , Neoplasias da Língua/patologia , Microambiente Tumoral , Fator C de Crescimento do Endotélio Vascular/genéticaRESUMO
Hepatocyte growth factor activator inhibitor-1 (HAI-1, also known as SPINT1) is an inhibitor of matriptase, a type-2 transmembrane protease widely expressed in epithelial cells. HAI-1 also functions as a chaperone to maintain the processing and localization of matriptase required for epithelial integrity. However, mechanisms underpinning the chaperone function remain to be elucidated. Here, we show that the first Kunitz domain (KD1) and the adjacent polycystic kidney disease (PKD) domain-like internal domain of HAI-1 are essential for the chaperone function. In HEK293T cells, which do not express endogenous HAI-1 or matriptase, forced matriptase overexpression was unsuccessful unless sufficient HAI-1 was co-expressed. Among mutant HAI-1 constructs, HAI-1 with inactivation mutation in KD1 (HAI-1mKD1) or HAI-1 lacking the PKD domain (HAI-1dPKD) was unable to support matriptase expression, and neither mutant formed a complex with activated matriptase. Matriptase did not localize to the cell surface when co-expressed with HAI-1dPKD. Moreover, HAI-1dPKD accumulated in the cytoplasm of HEK293T and HaCaT cells rather than localizing to the cell surface, presumably due to misfolding as judged by altered antibody recognition. On the other hand, activationlocked and activity-incompetent matriptase were stable and readily overexpressed and localized to the cell surface without HAI-1. Therefore, the observed matriptase instability was caused by its own catalytic activity in the absence of inhibitory HAI-1. The matriptase chaperone function of HAI-1 is thus mediated primarily by the inhibition of undesired intracellular matriptase activity, and the PKD domain is essential for the proper folding and trafficking of inhibitory HAI-1 and its chaperone function.
Assuntos
Doenças Renais Policísticas , Proteínas Secretadas Inibidoras de Proteinases , Serina Endopeptidases , Células HEK293 , Humanos , Doenças Renais Policísticas/metabolismo , Proteínas Secretadas Inibidoras de Proteinases/metabolismo , Serina Endopeptidases/metabolismoRESUMO
Leukemia stem cells (LSCs) in chronic myeloid leukemia (CML) are quiescent, insensitive to BCR-ABL1 tyrosine kinase inhibitors (TKIs) and responsible for CML relapse. Therefore, eradicating quiescent CML LSCs is a major goal in CML therapy. Here, using a G0 marker (G0M), we narrow down CML LSCs as G0M- and CD27- double positive cells among the conventional CML LSCs. Whole transcriptome analysis reveals NF-κB activation via inflammatory signals in imatinib-insensitive quiescent CML LSCs. Blocking NF-κB signals by inhibitors of interleukin-1 receptor-associated kinase 1/4 (IRAK1/4 inhibitors) together with imatinib eliminates mouse and human CML LSCs. Intriguingly, IRAK1/4 inhibitors attenuate PD-L1 expression on CML LSCs, and blocking PD-L1 together with imatinib also effectively eliminates CML LSCs in the presence of T cell immunity. Thus, IRAK1/4 inhibitors can eliminate CML LSCs through inhibiting NF-κB activity and reducing PD-L1 expression. Collectively, the combination of TKIs and IRAK1/4 inhibitors is an attractive strategy to achieve a radical cure of CML.
Assuntos
Quinases Associadas a Receptores de Interleucina-1/efeitos dos fármacos , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mieloide/tratamento farmacológico , Células-Tronco Neoplásicas/metabolismo , Animais , Antineoplásicos/farmacologia , Doença Crônica , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Proteínas de Fusão bcr-abl/metabolismo , Humanos , Mesilato de Imatinib/farmacologia , Inibidores de Checkpoint Imunológico/farmacologia , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Masculino , Camundongos , Pessoa de Meia-Idade , Inibidores de Proteínas Quinases/farmacologiaRESUMO
We describe the case of a 40s woman with a carbohydrate antigen (CA)19-9-producing splenic cyst. The lesion was detected incidentally at the splenic hilum, and resected after 5 years of follow-up. Size of the lesion was enlarged from 1.6 cm to 5.3 cm, and serum CA19-9 was elevated from the normal range to 1766 U/ml. Microscopically, CA19-9-producing splenic cyst was diagnosed. It was mimicked pancreatic malignancy due to its location at the splenic hilum. Benign lesions with elevated serum CA19-9 also to be differential diagnosis.
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Lateral lymph node (LLN) metastasis is one of the forms of local recurrence after surgery for lower rectal cancer. We here present a case of LLN recurrence of rectal cancer that was shown by laparoscopic lateral lymph node dissection (LLND) to have a complete pathological response to chemotherapy. A 58-year-old man underwent open low anterior resection for lower rectal cancer. After detection of right LLN recurrence 43 months after the operation, 11 cycles of capecitabine, oxaliplatin, and bevacizumab chemotherapy were administered. Laparoscopic right LLND was performed 55 months after the first operation. Pathological examination revealed no viable tumor cells in the dissected lymph nodes. The patient remains alive without recurrence 61 months after the first surgery and 6 months after laparoscopic LLND. Laparoscopic LLND for LLN recurrence of rectal cancer is feasible and should be considered a valid treatment option.
Assuntos
Laparoscopia , Neoplasias Retais , Humanos , Excisão de Linfonodo , Linfonodos/cirurgia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/cirurgia , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/cirurgiaRESUMO
Cell behavior is controlled by complex gene regulatory networks. Although studies have uncovered diverse roles of individual genes, it has been challenging to record or control sequential genetic events in living cells. In this study, we designed two cellular chain reaction systems that enable sequential sgRNA activation in mammalian cells using a nickase Cas9 tethering of a cytosine nucleotide deaminase (nCas9-CDA). In these systems, thymidine (T)-to-cytosine (C) substitutions in the scaffold region of the sgRNA or the TATA box-containing loxP sequence (TATAloxP) are corrected by the nCas9-CDA, leading to activation of the next sgRNA. These reactions can occur multiple times, resulting in cellular chain reactions. As a proof of concept, we established a chain reaction by repairing sgRNA scaffold mutations in 293 T cells. Importantly, the results obtained in yeast or in vitro did not match those obtained in mammalian cells, suggesting that in vivo chain reactions need to be optimized in appropriate cellular contexts. Our system may lay the foundation for building cellular chain reaction systems that have a broad utility in the future biomedical research.
Assuntos
Sistemas CRISPR-Cas , Reparo do DNA , Edição de Genes , Mutação , RNA Guia de Cinetoplastídeos/genética , Citosina Desaminase/genética , Citosina Desaminase/metabolismo , Células HEK293 , Humanos , TATA Box/genética , Timidina/genéticaRESUMO
BACKGROUND: The most common presentation of symptomatic Meckel's diverticulum (MD) are intestinal obstruction, gastrointestinal hemorrhage, and inflammation of the MD with or without perforation. Intraperitoneal hemorrhage because of MD is extremely rare. We report a case of MD with intraperitoneal hemorrhage in a child detected with screening laparoscopy. CASE PRESENTATION: An 11-year-old girl presented to another hospital with lower abdominal pain and vomiting that lasted for 2 days. Acute appendicitis was suspected, and she was referred to our department. Abdominal enhanced computed tomography showed an abscess in the lower abdomen with ascites in the pelvis. She was diagnosed with a localized intra-abdominal abscess and the decision was made to treat with antibiotics. However, her abdominal pain worsened, with abdominal distension, tenderness and guarding. She was diagnosed with panperitonitis and the decision was made for surgery 5 h after admission. During surgery, laparoscopic observation from the umbilical region revealed 200 ml of fresh blood throughout the peritoneal cavity, originating from the mesentery of the ileum. MD was observed with bleeding from the surrounding mesentery. Small bowel resection was performed, and the patient was discharged on the 5th postoperative day. Pathological findings revealed an MD containing ectopic gastric mucosa and small intestinal ulcer perforation at the base of the MD. CONCLUSIONS: We report an extremely rare case of an MD with intraperitoneal hemorrhage in a child. In pediatric cases, it is possible that perforation with ectopic gastric mucosa may cause massive bleeding because of rupture of the surrounding mesenteric blood vessels.
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INTRODUCTION: Cutaneous metastasis of urothelial carcinoma is uncommon. We experienced a case of cutaneous metastasis that emerged during chemotherapy and progressed rapidly during immunotherapy for bladder tumor with lymph node metastasis. CASE PRESENTATION: A 77-year-old female patient received chemotherapy using gemcitabine and cisplatin for bladder urothelial carcinoma with para-aortic and pelvic lymph node metastases (clinical stage T2N1M1). After eight courses of chemotherapy, skin rash appeared in the lower abdomen with leg edema caused by multiple lymphadenopathy. Skin biopsy revealed cutaneous metastasis of urothelial carcinoma. The cutaneous tumor progressed rapidly and the patient died 5 weeks after the start of second-line pembrolizumab treatment. CONCLUSION: A patient with cutaneous metastasis of urothelial carcinoma that emerged during chemotherapy had poor prognosis and lack of efficacy of an immune checkpoint inhibitor.