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1.
Am J Surg ; : 115809, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38945726

RESUMO

BACKGROUND: Secondary adrenal tumors (SATs) are uncommon, and the benefits of adrenalectomy for SATs have not been well-established. A systematic review and meta-analysis were conducted to assess the survival benefits of adrenalectomy for SATs. METHOD: ology: A systematic literature search was performed (1990-2022). The inclusion criteria included a known primary tumor with confirmed adrenal metastasis in patients who underwent adrenalectomy. The primary outcome was the overall survival (OS). RESULTS: A total of 26 studies were included, with 2279 patients. The average age at the time of diagnosis was 61.1 years. Lung cancer was the most common primary tumor. The average time from primary tumor diagnosis to identification of adrenal metastasis was 17 months. The median OS was 35.2 months. One, three, and five-year OS were 79.7 â€‹%, 49.1 â€‹%, and 37.9 â€‹%, respectively. CONCLUSION: The results of this review provide insight into the long-term survival of patients with SATs who underwent adrenalectomy. The study highlights the need for further research to identify the risk factors that play a role in the outcome of adrenalectomy in patients with SATs.

2.
Clin Transl Med ; 13(12): e1513, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38131168

RESUMO

BACKGROUND: The majority of pancreatic ductal adenocarcinoma (PDAC) patients experience disease progression while on treatment with gemcitabine and nanoparticle albumin-bound (nab)-paclitaxel (GemPac) necessitating the need for a more effective treatment strategy for this refractory disease. Previously, we have demonstrated that nuclear exporter protein exportin 1 (XPO1) is a valid therapeutic target in PDAC, and the selective inhibitor of nuclear export selinexor (Sel) synergistically enhances the efficacy of GemPac in pancreatic cancer cells, spheroids and patient-derived tumours, and had promising activity in a phase I study. METHODS: Here, we investigated the impact of selinexor-gemcitabine-nab-paclitaxel (Sel-GemPac) combination on LSL-KrasG12D/+ ; LSL-Trp53R172H/+ ; Pdx1-Cre (KPC) mouse model utilising digital spatial profiling (DSP) and single nuclear RNA sequencing (snRNAseq). RESULTS: Sel-GemPac synergistically inhibited the growth of the KPC tumour-derived cell line. The Sel-GemPac combination reduced the 2D colony formation and 3D spheroid formation. In the KPC mouse model, at a sub-maximum tolerated dose (sub-MTD) , Sel-GemPac enhanced the survival of treated mice compared to controls (p < .05). Immunohistochemical analysis of residual KPC tumours showed re-organisation of tumour stromal architecture, suppression of proliferation and nuclear retention of tumour suppressors, such as Forkhead Box O3a (FOXO3a). DSP revealed the downregulation of tumour promoting genes such as chitinase-like protein 3 (CHIL3/CHI3L3/YM1) and multiple pathways including phosphatidylinositol 3'-kinase-Akt (PI3K-AKT) signalling. The snRNAseq demonstrated a significant loss of cellular clusters in the Sel-GemPac-treated mice tumours including the CD44+ stem cell population. CONCLUSION: Taken together, these results demonstrate that the Sel-GemPac treatment caused broad perturbation of PDAC-supporting signalling networks in the KPC mouse model. HIGHLIGHTS: The majority of pancreatic ductal adenocarcinoma (PDAC) patients experience disease progression while on treatment with gemcitabine and nanoparticle albumin-bound (nab)-paclitaxel (GemPac). Exporter protein exportin 1 (XPO1) inhibitor selinexor (Sel) with GemPac synergistically inhibited the growth of LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx1-Cre (KPC) mouse derived cell line and enhanced the survival of mice. Digital spatial profiling shows that Sel-GemPac causes broad perturbation of PDAC-supporting signalling in the KPC model.


Assuntos
Carcinoma Ductal Pancreático , Combinação de Medicamentos , Proteína Exportina 1 , Neoplasias Pancreáticas , Animais , Camundongos , Modelos Animais de Doenças , Neoplasias Pancreáticas/tratamento farmacológico , Carcinoma Ductal Pancreático/tratamento farmacológico , Proteína Exportina 1/antagonistas & inibidores , Gencitabina/administração & dosagem , Paclitaxel/administração & dosagem , Hidrazinas/administração & dosagem , Triazóis/administração & dosagem , Microambiente Tumoral , Análise da Expressão Gênica de Célula Única , Humanos
3.
Surg Endosc ; 37(1): 715-722, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35562508

RESUMO

INTRODUCTION: Minimally invasive or open Graham Patch repair remains the gold standard approach for management of perforated peptic ulcers (PPU). Herein, we report outcomes of laparoscopic technique and compare it with open approach at a community hospital. METHODS: Retrospective observational study conducted comparing laparoscopic modified Cellan-Jones repair (mCJR) versus the standard open repair of PPU. Patients aged 18-90 years during 2016-2021 were offered either a minimally invasive or open approach depending on surgeon laparoscopic capability, and were compared in terms of demographics, co-morbidities, intra-operative details, and short-term outcomes. RESULTS: A total of 49 patients were included (46.9% males, mean age 52.9 years, mean BMI 25.0, ASA ≥ III 75.5%, 75.5% smokers, 26.5% current NSAIDs use, and 71.4% alcohol drinkers). Duodenum was the most common perforation site (57.1%), and majority of ulcers were 1-2 cm (72.9%). Laparoscopic approach was performed in 16 consecutive patients (32.7%) by a single surgeon, with no conversions. Preoperative characteristics were similar for both groups. Compared to open approach, laparoscopic group were taken to operation immediately (< 4 h) (87.5% vs. 15.2%, p < 0.001), had lower estimated blood loss (11.8 ml vs. 73.8 ml, p = 0.063), and longer operative time (117.1 min vs. 85.6 min, p = 0.010). Postoperatively, nasogastric tube was removed earlier in laparoscopic group (POD1-2, 87.5% vs. 24.2%, p = 0.001), with earlier resumption of diet (POD1-2, 62.6% vs. 9.1%, p = 0.002), less narcotic usage (< 3 days, 58.3% vs. 6.1%, p < 0.001), earlier return of bowel function (POD1-2, 43.8% vs. 9.1%, p = 0.003) and shorter length of stay (LOS) (3.7 days vs. 16.1 days, p < 0.001). Both in-house mortality and morbidity rates were lower in the laparoscopic group, but not statistically significant [(0% vs. 6.1%, p = 0.347) and (12.5% vs. 39.4%, p = 0.500), respectively]. CONCLUSION: Laparoscopic mCJR is a feasible method for repair of PPU, and it is associated with shorter LOS, and less narcotics usage in comparison to the open repair approach.


Assuntos
Laparoscopia , Úlcera Péptica Perfurada , Masculino , Humanos , Pessoa de Meia-Idade , Feminino , Resultado do Tratamento , Hospitais Comunitários , Complicações Pós-Operatórias/etiologia , Laparoscopia/métodos , Estudos Retrospectivos , Úlcera Péptica Perfurada/cirurgia , Úlcera Péptica Perfurada/etiologia , Tempo de Internação
4.
J Surg Case Rep ; 2022(4): rjac138, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35495083

RESUMO

Pancreatic cancer has a low survival rate even after ostensible complete resection, and treatment for recurrence is usually only palliative. However, rare solitary metastasis can occur and may be operable. In this report, we describe such a case and review the literature on metastasectomy for pancreatic adenocarcinoma. A 66-year-old female underwent Whipple procedure at our institution in 2014 for a pT3N0 pancreatic adenocarcinoma. A slowly growing umbilical mass was noted 6 years later with concomitant rise in her CA 19-9 levels. CT-guided biopsy of her abdominal wall mass confirmed a well-differentiated adenocarcinoma consistent with her primary pancreatic cancer. The patient underwent metastasectomy of the isolated abdominal wall mass, with negative margins. She received no further postoperative treatment. The patient remains disease and symptom-free over 18 months after resection of the metastasis. In highly selected cases of pancreatic adenocarcinoma, resection of solitary metastasis may be therapeutic.

5.
Cureus ; 14(1): e21782, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35251852

RESUMO

A malignant peripheral nerve sheath tumor (MPNST) is an aggressive tumor that can arise from the malignant transformation of benign neurofibromas in patients with neurofibromatosis type 1 (NF1). MPNST occurs in 2% of patients with NF1, contributing to significant mortality in these patients. Here, we report the case of a 67-year-old female with a known history of neurofibromatosis type 1 who was referred to general surgery after the discovery of a large left-sided adrenal mass on CT imaging five months earlier. Lab workup revealed elevated urine catecholamines, concerning pheochromocytoma. As pheochromocytoma is also common in those with NF-1, appropriate medical management followed by surgical resection was performed. The final pathology report revealed an MPNST.

6.
BMJ Case Rep ; 14(8)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34413045

RESUMO

Three distinct gastric carcinoid (GC) tumour types have been described based on differing biological behaviour and prognoses. Type I GC tumours account for the vast majority (70%-80%), are associated with chronic atrophic gastritis and have a low metastatic potential. Type II carcinoid tumours are the least common (5%-10%), are related to Zollinger-Ellison syndrome and occur in relation to multiple neoplasia type I. Sporadic type III tumours (15%-25%) are the most aggressive type, are unrelated to gastrin over secretion and carry the worst prognosis. In this case report, we present a patient with longstanding gastroesophageal reflux disease (GERD) who presented with epigastric abdominal pain and tarry stools and was found to have a large gastric polyp on endoscopy. Despite current literature recommending surgical resection for larger GC tumours, endoscopic resection was successfully used to excise the tumour with pathology demonstrating complete resection with negative margins.


Assuntos
Tumor Carcinoide , Gastrite Atrófica , Neoplasias Gástricas , Síndrome de Zollinger-Ellison , Tumor Carcinoide/cirurgia , Endoscopia , Humanos , Neoplasias Gástricas/cirurgia
8.
Sci Rep ; 7(1): 1538, 2017 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-28484210

RESUMO

Treponema pallidum subsp. pallidum, the causative agent of syphilis, is a highly invasive spirochete pathogen that uses the vasculature to disseminate throughout the body. Identification of bacterial factors promoting dissemination is crucial for syphilis vaccine development. An important step in dissemination is bacterial adhesion to blood vessel surfaces, a process mediated by bacterial proteins that can withstand forces imposed on adhesive bonds by blood flow (vascular adhesins). The study of T. pallidum vascular adhesins is hindered by the uncultivable nature of this pathogen. We overcame these limitations by expressing T. pallidum adhesin Tp0751 (pallilysin) in an adhesion-attenuated strain of the cultivable spirochete Borrelia burgdorferi. Under fluid shear stress representative of conditions in postcapillary venules, Tp0751 restored bacterial-vascular interactions to levels similar to those observed for infectious B. burgdorferi and a gain-of-function strain expressing B. burgdorferi vascular adhesin BBK32. The strength and stability of Tp0751- and BBK32-dependent endothelial interactions under physiological shear stress were similar, although the mechanisms stabilizing these interactions were distinct. Tp0751 expression also permitted bacteria to interact with postcapillary venules in live mice as effectively as BBK32-expressing strains. These results demonstrate that Tp0751 can function as a vascular adhesin.


Assuntos
Adesinas Bacterianas/metabolismo , Borrelia burgdorferi/genética , Expressão Gênica , Doença de Lyme/microbiologia , Treponema pallidum/metabolismo , Vênulas/microbiologia , Animais , Aderência Bacteriana , Endotélio/microbiologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Masculino , Camundongos Endogâmicos C57BL , Resistência ao Cisalhamento , Estresse Mecânico
9.
Cell Rep ; 16(10): 2593-2604, 2016 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-27568563

RESUMO

Systemic dissemination of microbes is critical for progression of many infectious diseases and is associated with most mortality due to bacterial infection. The physical mechanisms mediating a key dissemination step, bacterial association with vascular endothelia in blood vessels, remain unknown. Here, we show that endothelial interactions of the Lyme disease spirochete Borrelia burgdorferi under physiological shear stress mechanistically resemble selectin-dependent leukocyte rolling. Specifically, these interactions are mediated by transfer of mechanical load along a series of adhesion complexes and are stabilized by tethers and catch bond properties of the bacterial adhesin BBK32. Furthermore, we found that the forces imposed on adhesive bonds under flow may be small enough to permit active migration driven by bacterial flagellar motors. These findings provide insight into the biomechanics of bacterial-vascular interactions and demonstrate that disseminating bacteria and circulating host immune cells share widely conserved mechanisms for interacting with endothelia under physiological shear stress.


Assuntos
Vasos Sanguíneos/microbiologia , Vasos Sanguíneos/patologia , Borrelia burgdorferi/fisiologia , Interações Hospedeiro-Patógeno , Aderência Bacteriana , Proteínas de Bactérias/metabolismo , Fenômenos Biomecânicos , Células Endoteliais/microbiologia , Células Endoteliais/patologia , Humanos , Migração e Rolagem de Leucócitos , Modelos Biológicos , Complexos Multiproteicos/metabolismo , Rotação , Estresse Mecânico , Torque , Vênulas/patologia , Vênulas/virologia
10.
PLoS One ; 11(2): e0149177, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26882284

RESUMO

The Jagn1 protein was indentified in a SILAC proteomic screen of proteins that are increased in insulinoma cells expressing a folding-deficient proinsulin. Jagn1 mRNA was detected in primary rodent islets and in insulinoma cell lines and the levels were increased in response to ER stress. The function of Jagn1 was assessed in insulinoma cells by both knock-down and overexpression approaches. Knock-down of Jagn1 caused an increase in glucose-stimulated insulin secretion resulting from an increase in proinsulin biosynthesis. In contrast, overexpression of Jagn1 in insulinoma cells resulted in reduced cellular proinsulin and insulin levels. Our results identify a novel role for Jagn1 in regulating proinsulin biosynthesis in pancreatic ß-cells. Under ER stress conditions Jagn1 is induced which might contribute to reducing proinsulin biosynthesis, in part by helping to relieve the protein folding load in the ER in an effort to restore ER homeostasis.


Assuntos
Estresse do Retículo Endoplasmático , Proteínas de Membrana/metabolismo , Proinsulina/biossíntese , Animais , Técnicas de Silenciamento de Genes , Células HeLa , Humanos , Insulina/metabolismo , Secreção de Insulina , Insulinoma/metabolismo , Ilhotas Pancreáticas/metabolismo , Camundongos , Proteínas Mutantes/metabolismo , Proteômica , Ratos
11.
Exp Cell Res ; 330(1): 111-22, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25447309

RESUMO

Endoplasmic reticulum (ER) stress is implicated in pancreatic ß-cell dysfunction and death resulting in type 2 diabetes. Activating transcription factor 6 (ATF6) is an essential component of the Unfolded Protein Response (UPR) and consists of two isoforms, ATF6α and ATF6ß. Here we investigated the role of ATF6ß. ATF6ß mRNA was detected in pancreatic ß-cell lines and rodent and human islets. We also detected ATF6ß protein and production of the active form (ATF6ßp60) in response to ER stress. Knock-down of ATF6ß in INS-1 832/13 insulinoma cells did not affect mRNA induction of several major UPR genes in response to ER stress, suggesting ATF6ß is not essential for the basic UPR. Expressing active ATF6ßp60 or ATF6αp50 followed by microarray analysis showed that they regulate similar UPR genes, although some genes such as Wfs1 are ATF6ß-specific. ATF6ß, but not ATF6α, is able to bind the Wfs1 promoter and induce Wfs1 gene and protein expression. Knock-down of ATF6ß increased the susceptibility of ß-cells to ER stress-induced apoptosis, while overexpression of active ATF6ßp60 reduced apoptosis. Thus, ATF6ß is not essential for induction of most UPR genes, but is required to maintain cell survival in ß-cells undergoing chronic ER stress, which in part relates to its ability to induce Wfs1, a pro-survival gene.


Assuntos
Fator 6 Ativador da Transcrição/metabolismo , Proteínas de Ligação a Calmodulina/metabolismo , Estresse do Retículo Endoplasmático , Células Secretoras de Insulina/metabolismo , Proteínas de Membrana/metabolismo , Fator 6 Ativador da Transcrição/genética , Animais , Apoptose , Proteínas de Ligação a Calmodulina/genética , Linhagem Celular , Sobrevivência Celular , Células Cultivadas , Humanos , Proteínas de Membrana/genética , Ligação Proteica , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Resposta a Proteínas não Dobradas
12.
BMC Cell Biol ; 15: 29, 2014 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-25011481

RESUMO

BACKGROUND: The Akita mutation (C96Y) in the insulin gene results in early onset diabetes in both humans and mice. Expression of mutant proinsulin (C96Y) causes endoplasmic reticulum (ER) stress in pancreatic ß-cells and consequently the cell activates the unfolded protein response (UPR). Since the proinsulin is terminally misfolded ER stress is irremediable and chronic activation of the UPR eventually activates apoptosis in some cells. Here we analyzed the IRE1-dependent activation of genes in response to misfolded proinsulin production in an inducible mutant proinsulin (C96Y) insulinoma cell line. RESULTS: The IRE1 endoribonuclease inhibitors 4µ8c and MKC-3946 prevented the splicing of the XBP1 mRNA in response to ER stress caused by mutant proinsulin production. Microarray expression analysis and qPCR validation of select genes revealed that maximal upregulation of many UPR genes in response to mutant proinsulin production required IRE1, although most were still increased above control. Interestingly, neither degradation of misfolded proinsulin via ER-associated degradation (ERAD), nor apoptosis induced by prolonged misfolded proinsulin expression were affected by inhibiting IRE1. CONCLUSIONS: Although maximal induction of most UPR genes requires IRE1, inhibition of IRE1 does not affect ERAD of misfolded proinsulin or predispose pancreatic ß-cells expressing misfolded proinsulin to chronic ER stress-induced apoptosis.


Assuntos
Apoptose/efeitos dos fármacos , Células Secretoras de Insulina/citologia , Proteínas de Membrana/antagonistas & inibidores , Proinsulina/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Resposta a Proteínas não Dobradas/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Regulação da Expressão Gênica/efeitos dos fármacos , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/metabolismo , Proteínas de Membrana/metabolismo , Mutação Puntual , Proinsulina/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteólise/efeitos dos fármacos , Ratos
13.
Mol Microbiol ; 86(5): 1116-31, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23095033

RESUMO

Systemic dissemination of microbial pathogens permits microbes to spread from the initial site of infection to secondary target tissues and is responsible for most mortality due to bacterial infections. Dissemination is a critical stage of disease progression by the Lyme spirochaete, Borrelia burgdorferi. However, many mechanistic features of the process are not yet understood. A key step is adhesion of circulating microbes to vascular surfaces in the face of the shear forces present in flowing blood. Using real-time microscopic imaging of the Lyme spirochaete in living mice we previously identified the first bacterial protein (B. burgdorferi BBK32) shown to mediate vascular adhesion in vivo. Vascular adhesion is also dependent on host fibronectin (Fn) and glycosaminoglycans (GAGs). In the present study, we investigated the mechanisms of BBK32-dependent vascular adhesion in vivo. We determined that BBK32-Fn interactions (tethering) function as a molecular braking mechanism that permits the formation of more stable BBK32-GAG interactions (dragging) between circulating bacteria and vascular surfaces. Since BBK32-like proteins are expressed in a variety of pathogens we believe that the vascular adhesion mechanisms we have deciphered here may be critical for understanding the dissemination mechanisms of other bacterial pathogens.


Assuntos
Aderência Bacteriana , Proteínas de Bactérias/metabolismo , Borrelia burgdorferi/fisiologia , Endotélio Vascular/metabolismo , Fibronectinas/metabolismo , Glicosaminoglicanos/metabolismo , Interações Hospedeiro-Patógeno , Animais , Proteínas de Bactérias/genética , Borrelia burgdorferi/genética , Borrelia burgdorferi/metabolismo , Endotélio Vascular/microbiologia , Doença de Lyme/microbiologia , Doença de Lyme/fisiopatologia , Camundongos , Ligação Proteica
14.
Am J Physiol Cell Physiol ; 302(7): C992-1003, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22189555

RESUMO

Activating transcription factor 6 (ATF6) is one of three principle endoplasmic reticulum (ER) stress response proteins and becomes activated when ER homeostasis is perturbed. ATF6 functions to increase ER capacity by stimulating transcription of ER-resident chaperone genes such as GRP78. Using an antibody that recognizes active ATF6α-p50, we found that active ATF6α was detected in insulinoma cells and rodent islets even under basal conditions and the levels were further increased by ER stress. To examine the function of ATF6α-p50, we depleted endogenous ATF6α-p50 levels using small interfering RNA in insulinoma cells. Knockdown of endogenous ATF6α-p50 levels by ∼60% resulted in a reduction in the steady-state levels of GRP78 mRNA and protein levels in nonstressed cells. Furthermore, ATF6α knockdown resulted in an apoptotic phenotype. We hypothesized that removal of the ATF6α branch of the unfolded protein response (UPR) would result in ER stress. However, neither the PKR-like endoplasmic reticulum kinase (PERK), nor the inositol requiring enzyme 1 (IRE1) pathways of the UPR were significantly activated in ATF6α knockdown cells, although these cells were more sensitive to ER stress-inducing compounds. Interestingly, phosphorylation of JNK, p38, and c-Jun were elevated in ATF6α knockdown cells and inhibition of JNK or p38 kinases prevented apoptosis. These results suggest that ATF6α may have a role in maintaining ß-cell survival even in the absence of ER stress.


Assuntos
Fator 6 Ativador da Transcrição/genética , Fator 6 Ativador da Transcrição/metabolismo , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Animais , Apoptose/fisiologia , Linhagem Celular Tumoral , Sobrevivência Celular/fisiologia , Células Cultivadas , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Chaperona BiP do Retículo Endoplasmático , Técnicas de Silenciamento de Genes , Células HeLa , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Insulinoma/genética , Insulinoma/metabolismo , Ilhotas Pancreáticas/metabolismo , MAP Quinase Quinase 4/genética , MAP Quinase Quinase 4/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-jun/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , RNA Mensageiro/genética , Ratos , Transdução de Sinais , Resposta a Proteínas não Dobradas , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
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