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1.
World J Oncol ; 15(2): 181-191, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38545475

RESUMO

Background: Spinster homologue 2 (SPNS2) is a transporter of sphingosine-1-phosphate (S1P), a bioactive lipid linked to cancer progression. We studied the link between SPNS2 gene expression, tumor aggressiveness, and outcomes in patients with hepatocellular carcinoma (HCC). Methods: Gene expression in patients with HCC was analyzed from the Cancer Genome Atlas (TCGA) (n = 350) and GSE76427 (n = 115) as a validation cohort, as well as liver tissue cohort GSE6764 (n = 75). Results: High-SPNS2 HCC was significantly associated with high level of lymph-angiogenesis-related factors. SPNS2 expression was significantly higher in normal liver and early HCC versus advanced HCC (P < 0.02). High SPNS2 levels enriched immune response-related gene sets; inflammatory, interferon (IFN)-α, IFN-γ responses, and tumor necrosis factor (TNF)-α, interleukin (IL)-6/Janus kinase/signal transducer and activator of transcription (JAK/STAT3) signaling, complement and allograft rejection, but did not significantly infiltrate specific immune cells nor cytolytic activity score. High-SPNS2 HCC enriched tumor aggravating pathway gene sets such as KRAS (Kirsten rat sarcoma virus) signaling, but inversely correlated with Nottingham histological grade, MKI67 (marker of proliferation Ki-67) expression, and cell proliferation-related gene sets. Further, high-SPNS2 HCC had significantly high infiltration of stromal cells, showing that low-SPNS2 HCC is highly proliferative. Finally, high-SPNS2 HCC was associated with better disease-free, disease-specific, and overall survival (P = 0.031, 0.046, and 0.040, respectively). Conclusions: Although SPNS2 expression correlated with lymph-angiogenesis and other cancer-promoting pathways, it also enriched immune response. SPNS2 levels were higher in normal liver compared to HCC, and inversely correlated with cancer cell proliferation and better survival. SPNS2 expression may be beneficial in HCC patients despite detrimental in-vitro effects.

4.
J Surg Res ; 295: 666-672, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38113610

RESUMO

INTRODUCTION: Cancer operations are increasingly utilizing specialized equipment and technology. Related costs are often not known to the responsible surgeon. We seek to evaluate cost aspects of care episodes attributable to the surgeon's management decisions. METHODS: Financial cost data in a tertiary academic cancer center were queried over 3 y. Consecutive patients undergoing gastrointestinal operations followed by inpatient admission of two or more days were included, excluding patients with 40+ d admissions. Analysis of variance, Kruskal-Wallis, and multiple regression statistics were utilized. RESULTS: The study population included 1540 patients: 54% men and 46% women, with a median age of 64 y (range 15-95). Eight surgeons conducted major (82%) and minor (18%) operations, with a minimally invasive surgical approach in 60.4%. Procedures included colorectal (37%), pancreatic (19%), esophagogastric (18%), hepatobiliary (18%), and small bowel resections (8%). Total direct costs differed between surgeons with an analysis of variance coefficient range between -$3265 and +$6163 (P < 0.001). Surgeons' cost differences were observed for central medical supply, operating room (OR) supply, total OR, inpatient room, laboratory, pharmacy, supportive care (P < 0.001), and radiology costs (P < 0.02). OR supply cost was the dominant consistent domain with significant differences between surgeons in all case subcategories. When controlled for case category and minimally invasive surgical approach, multiple regression showed the most significant variations between surgeons in ORs, medical supply, and nutrition costs (P < 0.001), followed by laboratory costs (P < 0.01). Top OR supply costs were staplers and energy devices. CONCLUSIONS: Even in a highly subspecialized surgical environment, surgeons' variable utilization of ORs and medical supplies is strongly linked to variations in care-related costs. Specific queries into supply items should reduce costs and optimize value generated.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório , Neoplasias , Cirurgiões , Masculino , Humanos , Feminino , Estudos Retrospectivos , Custos e Análise de Custo , Hospitalização
5.
Ann Surg Oncol ; 30(13): 7986-7995, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37775686

RESUMO

BACKGROUND: The sequence of localized and systemic treatment for colorectal liver metastases (CRLM) remains debated. Our objective is to analyze the effect of treatment sequence on overall survival (OS) in patients with CRLM using a large cancer database. PATIENTS AND METHODS: The national cancer database (NCDB) was utilized to identify patients with stage IV colorectal cancer (CRC) diagnosed between 2004 and 2016. OS was analyzed using standard univariate and multivariate methods. RESULTS: We identified 72,376 patients with synchronous CRLM, of whom 43,039 had liver-only metastases. Patients with liver-only CRLM had a median OS of 18.9 months, versus those with CRLM plus extrahepatic sites (11.3 months). In patients with liver-only CRLM, resection of both the primary and metastatic site was associated with median OS 38.9 months versus 30.2 months after resection of the metastatic site alone, and resection of the primary tumor alone (22.3 months, all p < 0.001). Receipt of perioperative chemotherapy correlated with a median OS of 44.7 months versus preoperative chemotherapy only (38.4 months) or postoperative chemotherapy only (27.9 months, all p < 0.001). Patients who received chemotherapy alone had a median OS of 16.4 months versus those who underwent resection without chemotherapy (9.5 months, p < 0.001). CONCLUSIONS: This study reveals a correlation between perioperative chemotherapy and superior OS in patients with liver-only CRLM, and shows that resection of the metastatic site was linked to better OS. Despite obvious cohort heterogeneity, the data can support a resection approach with additional, preferably peri- or preoperative systemic therapy for patients with CRLM.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hepatectomia , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/cirurgia , Terapia Neoadjuvante , Estudos Retrospectivos
6.
J Surg Case Rep ; 2023(7): rjad411, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37528912

RESUMO

The incidence of bilateral adrenal hemorrhage (BAH) in the postoperative setting is rare, but potentially life threatening. A literature review of postoperative BAH reveals that there is limited data on BAH following abdominal surgery. We present a case of BAH following pancreaticoduodenectomy, which has not been previously documented in the literature. A 70-year-old male patient with no previous history of adrenal disease underwent an uncomplicated pancreaticoduodenectomy and was discharged after a typical postoperative course. He was readmitted with abdominal pain and ileus on POD 8 and a computed tomography (CT) scan was initially unremarkable, but a repeat CT scan on POD 11 demonstrated BAH. He was found to have adrenal insufficiency and was successfully treated with steroids. Clinicians should be aware of the possibility of adrenal hemorrhage postoperatively as it can potentially be a fatal surgical complication. To enhance patient outcomes, early detection and appropriate treatment are essential.

7.
World J Oncol ; 14(3): 178-187, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37350807

RESUMO

Background: Immune checkpoint inhibitors (ICIs) such as programmed cell death protein-1 (PD-1) inhibitors or PD-1 ligand-1 (PD-L1) inhibitors have led to remarkable improvement in outcomes of non-small cell lung cancer (NSCLC). Unfortunately, the significant benefits of ICI therapy are frequently limited by resistance to treatment and adverse effects, and the predictive value of pre-treatment tumor tissue PD-L1 expression is limited. Development of less invasive biomarkers that could identify responders and non-responders in early on-treatment could markedly improve the treatment regimen. Accumulating evidence suggests that baseline gut microbiota profile is associated with response to PD-1/PD-L1 blockade therapy. However, change in the gut microbiome composition during PD-1/PD-L1 blockade therapy and its relation to response remain unclear. Methods: Here, we analyzed pre- and on-treatment fecal samples from five NSCLC patients receiving anti-PD-1 immunotherapy, alone or in tandem with chemotherapy, and performed 16S rRNA sequencing. Results: The overall alpha diversity of the baseline gut microbiome was similar between three responders and two non-responders. While the gut microbiome composition remained stable overall during treatment (R2 = 0.145), responders showed significant changes in microbiome diversity between pre- and on-treatment samples during anti-PD-1 therapy compared to non-responders (P = 0.0274). Within the diverse microbiota, responders showed decreases in the abundance of genera Odoribacter, Gordonibacter, Candidatus Stoquefichus, Escherichia-Shigella, and Collinsella, and increase in abundance of Clostridium sensu stricto 1. In contrast, non-responders demonstrated on-treatment increases in genera Prevotella, Porphyromonas, Streptococcus, and Escherichia-Shigella, and decrease in abundance of Akkermansia. Conclusions: This pilot study identified a substantial change in gut microbiome diversity between pre- and on-treatment samples in NSCLC patients responding to anti-PD-1 therapy compared to non-responders. Our findings highlight the potential utility of gut microbiota dynamics as a noninvasive biomarker to predict response to PD-1/PD-L1 blockade therapy for a wide variety of malignancies, which sets a path for future investigation in larger prospective studies.

8.
Surg Open Sci ; 13: 94-98, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37274136

RESUMO

Background: Incisional herniae (IH) are reported in 5->20 % of patients undergoing open celiotomy, and can be linked to closure technique. The STITCH randomized trial favors a small bite technique for midline celiotomy closure with a 1-year IH rate of 13 % over larger bites (23 %). Methods: A continuous musculofascial mass closure with absorbable looped #1 PDS suture with 2-cm bite size was used for all open celiotomies. IH frequency and associated clinicopathologic factors were retrospectively analyzed from prospective data in 336 consecutive patients undergoing visceral resections by a single surgeon. Results: The study population included 192 men and 144 women, 81 % of whom had a cancer diagnosis, who underwent hepatobiliary, pancreatic, gastroesophageal, and colorectal resections, or a combination. The majority of patients (84 %) had subcostal incisions, and 10 % received a midline incision. At a median follow-up of 19.5 months, the overall IH rate was 3.3 %. Hernia rates were 2.5 % for subcostal margin, 2.9 % for midline, and 5.5 % for other incisions (p = 0.006). Median time to hernia detection was 492 days. Factors associated with IH were increased weight, abdominal depth/girth, male sex, spleen size, visceral fat, and body height (p ≤ 0.04 for all), but not type of resection, prior operations, underlying diagnosis, weight loss, adjuvant chemotherapy or radiation, incision length or suture to incision ratio. Conclusions: The described technique leads to a low IH rate of <3 % in subcostal or midline incisions, and can be recommended for routine use. The observed results appear superior to those of the STITCH trial, even for the smaller midline incision cohort.

9.
Cancer Res Commun ; 3(3): 510-520, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-37009132

RESUMO

Lack of reliable predictive biomarkers is a major limitation of combination therapy with chemotherapy and anti-programmed cell death protein 1/programmed death-ligand 1 (anti-PD-1/PD-L1) therapy (chemo-immunotherapy). We previously observed that the increase of peripheral blood CD8+ T cells expressing CX3CR1, a marker of differentiation, correlates with response to anti-PD-1 therapy; however, the predictive and prognostic value of T-cell CX3CR1 expression during chemo-immunotherapy is unknown. Here, we evaluated the utility of circulating CX3CR1+CD8+ T cells as a predictive correlate of response to chemo-immunotherapy in patients with non-small cell lung cancer (NSCLC). At least 10% increase of the CX3CR1+ subset in circulating CD8+ T cells from baseline (CX3CR1 score) was associated with response to chemo-immunotherapy as early as 4 weeks with 85.7% overall accuracy of predicting response at 6 weeks. Furthermore, at least 10% increase of the CX3CR1 score correlated with substantially better progression-free (P = 0.0051) and overall survival (P = 0.0138) on Kaplan-Meier analysis. Combined single-cell RNA/T-cell receptor (TCR) sequencing of circulating T cells from longitudinally obtained blood samples and TCR sequencing of tumor tissue from the same patient who received a long-term benefit from the treatment demonstrated remarkable changes in genomic and transcriptomic signatures of T cells as well as evolution of TCR clonotypes in peripheral blood containing highly frequent tumor-infiltrating lymphocyte repertoires overexpressing CX3CR1 early after initiation of the treatment despite stable findings of the imaging study. Collectively, these findings highlight the potential utility of T-cell CX3CR1 expression as a dynamic blood-based biomarker during the early course of chemo-immunotherapy and a marker to identify frequent circulating tumor-infiltrating lymphocyte repertoires. Significance: Current approaches to combined chemotherapy and anti-PD-1/PD-L1 therapy (chemo-immunotherapy) for patients with NSCLC are limited by the lack of reliable predictive biomarkers. This study shows the utility of T-cell differentiation marker, CX3CR1, as an early on-treatment predictor of response and changes in genomic/transcriptomic signatures of circulating tumor-infiltrating lymphocyte repertoires in patients with NSCLC undergoing chemo-immunotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Prognóstico , Neoplasias Pulmonares/tratamento farmacológico , Antígeno B7-H1/análise , Linfócitos T CD8-Positivos/química , Imunoterapia/métodos , Receptores de Antígenos de Linfócitos T/genética , Receptor 1 de Quimiocina CX3C/genética
10.
Heliyon ; 9(2): e13571, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36865476

RESUMO

Betel-nut leaf plate fiber (BLPF) is a lingo-cellulosic natural fiber that can be used to make eco-friendly and biodegradable blended or hybrid fabric with Banana fiber. In the world of organic textiles, naturally dyed BLPF-Banana fiber can be used for wearable products and satisfy health and hygiene issues. BLPF and Banana fiber can be good natural fibers for hybrid fabrics despite being considered waste materials. In this research work, both of the fibers were pretreated carefully to get the desired fineness, color, flexibilities, etc., which are necessary to manufacture fabric. BLPF-Banana woven (1 × 1) hybrid fabric was developed where 12 Ne Banana yarns were used in the warp direction, and 20 Ne BLPF yarns were used in the weft direction and it was dyed naturally with Turmeric. Evaluations of different physico-mechanical properties; tensile strength (854.9 N), tearing strength (14.5 N), stiffness (3.1 N), crease recovery (75° angle), and fabric thickness (1.33 mm) of naturally dyed BLPF-Banana blended fabric were tested, and found satisfactory. SEM, FTIR, and Water vapor transmission tests were also conducted in this study. It attempted to turn the wastages into an asset to make a unique biodegradable BLPF-Banana hybrid fabric by blending two types of natural fibers with the help of natural dyeing substance; it could be a god replacement for synthetic blended fabric.

12.
Biol Trace Elem Res ; 201(10): 5000-5036, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36633786

RESUMO

Selenium is a trace element required for the active function of numerous enzymes and various physiological processes. In recent years, selenium nanoparticles draw the attention of scientists and researchers because of its multifaceted uses. The process involved in chemically synthesized SeNPs has been found to be hazardous in nature, which has paved the way for safe and ecofriendly SeNPs to be developed in order to achieve sustainability. In comparison to chemical synthesis, SeNPs can be synthesized more safely and with greater flexibility utilizing bacteria, fungi, and plants. This review focused on the synthesis of SeNPs utilizing bacteria, fungi, and plants; the mechanisms involved in SeNP synthesis; and the effect of various abiotic factors on SeNP synthesis and morphological characteristics. This article discusses the synergies of SeNP synthesis via biological routes, which can help future researchers to synthesize SeNPs with more precision and employ them in desired fields.


Assuntos
Nanopartículas , Selênio , Bactérias , Selênio/farmacologia
16.
Ann Surg Oncol ; 30(3): 1630-1641, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36396870

RESUMO

BACKGROUND: Pancreatic cancer (PC) has an extremely high mortality rate, where obstructive jaundice due to cholestasis is a classic symptom. Conjugated bile acids (CBAs) such as taurocholic acid (TCA) have been reported to activate both the ERK1/2 and AKT signaling pathways via S1P receptor 2 (S1PR2) and promote growth of cholangiocarcinoma. Thus, we hypothesize that CBAs, which accumulate in cholestasis, accelerate PC progression via S1PR2. METHODS: Murine Panc02-luc and human AsPC-1, MIA PaCa2, and BxPC-3 cells were treated with TCA, S1PR2 agonist CYM5520, S1PR2 antagonist JTE-013, sphingosine-1-phosphate (S1P), and functional S1P receptor antagonist (except S1PR2) FTY720. Bile duct ligation (BDL) was performed on liver implantation or intraperitoneal injection of Panc02-luc cells. RESULTS: Panc02-luc and AsPC-1 cells predominantly expressed S1PR2, and their growth and migration were stimulated by TCA or CYM5520 in dose-dependent manner, which was blocked by JTE-013. This finding was not seen in PC cell lines expressing other S1P receptors than S1PR2. Panc02-luc growth stimulation by S1P was not blocked by FTY720. BDL significantly increased PC liver metastasis compared with sham. PC peritoneal carcinomatosis was significantly worsened by BDL, confirmed by number of nodules, tumor weight, bioluminescence, Ki-67 stain, ascites, and worse survival compared with sham. CYM5520 significantly worsened PC carcinomatosis, whereas treatment with anti-S1P antibody or FTY720 also worsened progression. CONCLUSIONS: CBAs accelerated growth of S1PR2 predominant PC both in vitro and in vivo. This finding implicates S1PR2 as a potential therapeutic target in metastatic S1PR2 predominant pancreatic cancer.


Assuntos
Neoplasias dos Ductos Biliares , Colestase , Neoplasias Hepáticas , Neoplasias Pancreáticas , Camundongos , Humanos , Animais , Receptores de Esfingosina-1-Fosfato , Receptores de Lisoesfingolipídeo/metabolismo , Cloridrato de Fingolimode , Colestase/tratamento farmacológico , Neoplasias Pancreáticas/tratamento farmacológico , Esteroides , Ácidos e Sais Biliares , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias dos Ductos Biliares/patologia
17.
Am J Cancer Res ; 12(8): 4001-4014, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36119815

RESUMO

Coagulation regulates angiogenesis in cancer, and is associated with tumor development and metastasis. To date, there have been no studies quantifying the state of intra-tumoral coagulation. We measured intra-tumoral coagulation gene expression using the "Hallmark-COAGULATION" gene set in the MSigDB, performing gene set variation analysis and then assigning a "coagulation score" to quantify gene expression. Clinical, histologic, and genetic data were analyzed in 807 gastric cancer patients from the TCGA_STAD and GSE84437 databases. Tumors with increased expression of pro-coagulation genes were consistently associated with higher AJCC T-categories (p = 0.018), lymph node metastasis (p = 0.036), and stage (p = 0.006) in both cohorts. Patients with high coagulation scores were found to have worse disease-specific survival and overall survival (OS) (p = 0.019 and 0.011, respectively) in TCGA, and worse OS in GSE84437 cohort (p = 0.012). Higher expression of pro-coagulation genes correlated with increased intra-tumoral angiogenesis, as well as increased proportions of lymphatic and microvascular endothelial cells, endothelial cells, and pericytes, calculated by xCell algorithm. High coagulation scores were significantly associated with low tumor mutation burden, but not with intratumor heterogeneity and homologous recombination deficiency. Gastric cancers with high coagulation scores contained higher amounts of M1 macrophages and dendritic cells, and low numbers of Th1 cells (all P<0.001). Genes for epithelial mesenchymal transition (EMT), myogenesis, apical junction, transforming growth factor (TGF)-ß signaling, and angiogenesis were enriched in high coagulation score-gastric cancers (all false discovery rate <0.25). In conclusion, gastric cancers expressing higher levels of pro-coagulation genes demonstrate increased angiogenesis, EMT, TGF-ß signaling and worse patient prognosis.

18.
Ocul Surf ; 26: 88-96, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35934279

RESUMO

PURPOSE: Corneal nerves comprise the densest sensory network in the body. Dysfunction of the corneal cold sensitive neurons (CSN) is implicated in ophthalmic disorders, including Dry Eye Disease, the most common ocular surface disorder. The preservative Benzalkonium chloride (BAK) and the mydriatic agent Phenylephrine hydrochloride (PHE) are considered to be inactive at the level of the CSNs. The purpose of this study is to test the impacts of continuous exposures to BAK or PHE at their clinically used concentrations on corneal nerve structure and function. METHODS: In vivo extracellular electrophysiology of the rat trigeminal ganglion was used to monitor CSN functional response to stimuli mimicking physiological states and stressors of the cornea. Corneal nerve structure was evaluated by immunostaining. RESULTS: Among the tested stimuli, cold probe receptive field stimulation and hyperosmolar stress were the most sensitive methods of detecting activity changes. CSN activity was attenuated after 30 min exposure to either PHE or BAK. After an hour-long washout period, BAK-treated neurons failed to recover activity while PHE-treated neurons showed signs of functional recovery. Intraepithelial nerve density was reduced and nerve fragmentation was increased in BAK-treated corneas, while PHE exposure left corneal nerves structurally intact. CONCLUSIONS: Our study suggests that prolonged ocular instillations of BAK or PHE alter CSN activity through two different processes - irreversible neuronal damage in the case of BAK vs. reversible attenuation in the case of PHE.


Assuntos
Compostos de Benzalcônio , Síndromes do Olho Seco , Ratos , Animais , Compostos de Benzalcônio/toxicidade , Conservantes Farmacêuticos , Córnea/inervação , Síndromes do Olho Seco/induzido quimicamente , Soluções Oftálmicas
19.
Artigo em Inglês | MEDLINE | ID: mdl-35881600

RESUMO

The Industrial Internet of Things (IIoT) has been introduced in an era of increasingly broad potentials in the medical industry. In recent years, IIoT-based healthcare applications have grown in popularity, with the majority of them relying on Wireless Body Area Network (WBAN) for flexibility. There have been a few recent works that have investigated SDN-based fog architecture for constructing smart healthcare systems. However, the best fog node from the fog layer must be identified and limit the transmission of unnecessary data. To address this issue, the Intelligent Software-defined Fog Architecture (i-Health) is developed in this work. Based on the prior data pattern of each patient, the controller will decide whether to send the data to the fog layer. Furthermore, we introduced the Fog Ranking Service (FRS) and Fog Probing Service (FPS) to select the best fog node. The performance comparison reveals that the proposed i-Health outperforms existing benchmark approaches.

20.
PLoS One ; 17(7): e0269818, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35862373

RESUMO

PURPOSE: We have previously reported that VEGF-B is more potent than VEGF-A in mediating corneal nerve growth in vitro and in vivo, and this stimulation of nerve growth appears to be different from stimulation of angiogenesis by these same ligands, at least in part due to differences in VEGF receptor activation. VEGF signaling may be modulated by a number of factors including receptor number or the formation of receptor hetero- vs. homodimers. In endothelial cells, VEGF receptor heterodimer (VEGR1/R2) activation after ligand binding and subsequent phosphorylation alters the activation of downstream signaling cascades. However, our understanding of these processes in neuronal cell types remains unclear. The purpose of this study was to identify the presence and distribution of VEGF Receptor-Ligand interactions in neuronal cells as compared to endothelial cells. METHODS: PC12 (rat neuronal cell line), MAEC (mouse aortic endothelial cell line), MVEC (mouse venous endothelial cell line) and HUVEC (human umbilical venous endothelial cell line; control group) were used. Cells were acutely stimulated either with VEGF-A (50 ng/µL) or VEGF-B (50 ng/µL) or "vehicle" (PBS; control group). We also isolated mouse trigeminal ganglion cells from thy1-YFP neurofluorescent mice. After treatment, cells were used as follows: (i) One group was fixed in 4% paraformaldehyde and processed for VEGFR1 and VEGFR2 immunostaining and visualized using confocal fluorescence microscopy and Total Internal Reflection (TIRF) microscopy; (ii) the second group was harvested in cell lysis buffer (containing anti-protease / anti-phosphatase cocktail), lysed and processed for immunoprecipitation (IP; Thermo Fisher IP kit) and immunoblotting (IB; LI-COR® Systems). Immunoprecipitated proteins were probed either with anti-VEGFR1 or anti-VEGFR2 IgG antibodies to evaluate VEGFR1-R2-heterodimerization; (iii) a third group of cells was also processed for Duolink Proximity Ligation Assay (PLA; Sigma) to assess the presence and distribution of VEGF-receptor homo- and heterodimers in neuronal and endothelial cells. RESULTS: TIRF and fluorescence confocal microscopy revealed the presence of VEGFR1 co-localized with VEGFR2 in endothelial and PC12 neuronal cells. Cell lysates immunoprecipitated with anti-VEGFR1 further validated the existence of VEGFR1-R2 heterodimers in PC12 neuronal cells. Neuronal cells showed higher levels of VEGFR1-R2 heterodimers as compared to endothelial cells whereas endothelial cells showed higher VEGFR2-R2 homodimers compared to neuronal cells as demonstrated by Duolink PLA. Levels of VEGFR1-R1 homodimers were very low in neuronal and endothelial cells. CONCLUSIONS: Differences in VEGF Receptor homo- and heterodimer distribution may explain the differential role of VEGF ligands in neuronal versus endothelial cell types. This may in turn influence VEGF activity and regulation of neuronal cell homeostasis.


Assuntos
Fator A de Crescimento do Endotélio Vascular , Fator B de Crescimento do Endotélio Vascular , Animais , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Ligantes , Camundongos , Ratos , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
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