RESUMO

The rupture of the anterior cruciate ligament is common during physical activities; however, when associated with a multiple ligament injury, it represents an uncommon condition. The diagnosis of this injury is commonly delayed or missed. Consequently, the incidence of this injury may in fact be higher than reported. We present a case of a 27-year-old man with complete tear of the anterior cruciate ligament and of the medial collateral ligament and partial tear of the posterior cruciate, lateral collateral and patellar ligaments treated surgically.

A ruptura do ligamento cruzado anterior é comum durante atividades físicas; entretanto, quando associada a lesão ligamentar múltipla, representa uma condição incomum. O diagnóstico desta lesão é comumente tardio ou esquecido. Consequentemente, a incidência desta lesão pode de facto ser superior à relatada. Apresentamos o caso de um homem de 27 anos com ruptura completa do ligamento cruzado anterior e do ligamento colateral medial e ruptura parcial dos ligamentos cruzado posterior, colateral lateral e patelar tratados cirurgicamente.

La rotura del ligamento cruzado anterior es común durante las actividades físicas; sin embargo, cuando se asocia con una lesión de múltiples ligamentos, representa una condición poco común. El diagnóstico de esta lesión comúnmente se retrasa o se pasa por alto. En consecuencia, la incidencia de esta lesión puede ser mayor de lo informado. Presentamos el caso de un varón de 27 años con rotura completa del ligamento cruzado anterior y del ligamento colateral medial y rotura parcial de los ligamentos cruzado posterior, colateral lateral y rotuliano tratados quirúrgicamente.

RESUMO

Cellular neurothekeoma (CN) is a benign dermal neoplasm that most often affects the head and neck region and rarely occurs in the oral mucosa. We report a rare case of CN with atypical features on the floor of the mouth and summarize the reported cases of oral CN in English-language literature. A 62-year-old woman presented with a 6-month history of a painless mass on the floor of the mouth. Histopathological analysis of the excised specimen revealed a proliferation of neoplastic cells with oval to spindle morphology arranged in a vaguely nested and multinodular architecture separated by scarce hyaline collagen within a predominantly myxoid-rich stroma. The tumor cells were positive for NSE, and CD63 (NKI/C3), and negative for S100 protein, CD34, and SMA. Thus, the final diagnosis was CN. In addition, we summarized all clinicopathological data on oral CNs reported in the English-language literature. Nineteen cases were reviewed. Among them, only one case affected the floor of the mouth of a young girl, in contrast to the present case that occurred in an elderly woman. CN is particularly rare in this location and may be a diagnostic challenge for oral pathologists due to its rarity and morphological similarity with other lesions.

RESUMO

Persistent HGF/Met signaling drives tumor growth and dissemination. Proteoglycans within the tumor microenvironment might control HGF availability and signaling by affecting its accessibility to Met (HGF receptor), likely defining whether acute or sustained HGF/Met signaling cues take place. Given that betaglycan (BG, also known as type III TGFß receptor or TGFBR3), a multi-faceted proteoglycan TGFß co-receptor, can be found within the tumor microenvironment, we addressed its hypothetical role in oncogenic HGF signaling. We found that HGF/Met promotes lung cancer and endothelial cells migration via PI3K and mTOR. This effect was enhanced by recombinant soluble betaglycan (solBG) via a mechanism attributable to its glycosaminoglycan chains, as a mutant without them did not modulate HGF effects. Moreover, soluble betaglycan extended the effect of HGF-induced phosphorylation of Met, Akt, and Erk, and membrane recruitment of the RhoGEF P-Rex1. Data-mining analysis of lung cancer patient datasets revealed a significant correlation between high MET receptor, HGF, and PREX1 expression and reduced patient survival. Soluble betaglycan showed biochemical interaction with HGF and, together, they increased tumor growth in immunocompetent mice. In conclusion, the oncogenic properties of the HGF/Met pathway are enhanced and sustained by GAG-containing soluble betaglycan.

RESUMO

The serine-threonine kinase Akt plays a fundamental role in cell survival, metabolism, proliferation, and migration. To keep these essential processes under control, Akt activity and stability must be tightly regulated; otherwise, life-threatening conditions might prevail. Although it is well understood that phosphorylation regulates Akt activity, much remains to be known about how its stability is maintained. Here, we characterize BAG5, a chaperone regulator, as a novel Akt-interactor and substrate that attenuates Akt stability together with Hsp70. BAG5 switches monoubiquitination to polyubiquitination of Akt and increases its degradation caused by Hsp90 inhibition and Hsp70 overexpression. Akt interacts with BAG5 at the linker region that joins the first and second BAG domains and phosphorylates the first BAG domain. The Akt-BAG5 complex is formed in serum-starved conditions and dissociates in response to HGF, coincident with BAG5 phosphorylation. BAG5 knockdown attenuated Akt degradation and facilitated its activation, whereas the opposite effect was caused by BAG5 overexpression. Altogether, our results indicate that Akt stability and signaling are dynamically regulated by BAG5, depending on growth factor availability.

Assuntos

Assuntos

RESUMO

Oncogenic Gαq causes uveal melanoma via non-canonical signaling pathways. This constitutively active mutant GTPase is also found in cutaneous melanoma, lung adenocarcinoma, and seminoma, as well as in benign vascular tumors, such as congenital hemangiomas. We recently described that PDZ-RhoGEF (also known as ARHGEF11), a canonical Gα12/13 effector, is enabled by Gαs Q227L to activate CdcIn addition, and we demonstrated that constitutively active Gαq interacts with the PDZ-RhoGEF DH-PH catalytic module, but does not affect its binding to RhoA or Cdc. This suggests that it guides this RhoGEF to gain affinity for other GTPases. Since RhoJ, a small GTPase of the Cdc42 subfamily, has been involved in tumor-induced angiogenesis and the metastatic dissemination of cancer cells, we hypothesized that it might be a target of oncogenic Gαq signaling via PDZ-RhoGEF. Consistent with this possibility, we found that Gαq Q209L drives full-length PDZ-RhoGEF and a DH-PH construct to interact with nucleotide-free RhoJ-G33A, a mutant with affinity for active RhoJ-GEFs. Gαq Q209L binding to PDZ-RhoGEF was mapped to the PH domain, which, as an isolated construct, attenuated the interaction of this mutant GTPase with PDZ-RhoGEF's catalytic module (DH-PH domains). Expression of these catalytic domains caused contraction of endothelial cells and generated fine cell sprouts that were inhibited by co-expression of dominant negative RhoJ. Using relational data mining of uveal melanoma patient TCGA datasets, we got an insight into the signaling landscape that accompanies the Gαq/PDZ-RhoGEF/RhoJ axis. We identified three transcriptional signatures statistically linked with shorter patient survival, including GPCRs and signaling effectors that are recognized as vulnerabilities in cancer cell synthetic lethality datasets. In conclusion, we demonstrated that an oncogenic Gαq mutant enables the PDZ-RhoGEF DH-PH module to recognize RhoJ, suggesting an allosteric mechanism by which this constitutively active GTPase stimulates RhoJ via PDZ-RhoGEF. These findings highlight PDZ-RhoGEF and RhoJ as potential targets in tumors driven by mutant Gαq.

Assuntos

RESUMO

The gingival cyst of the adult (GCA) is a rare odontogenic cyst, consisting of 0.3% of all odontogenic cysts. This case report, based on CARE guidelines for case reports, aims to present a case of a 52-year-old female patient with a symptomatic translucent nodule in the upper left anterior gingiva, measuring approximately 6mm. Excisional biopsy was performed, and the histological examination revealed multiple cystic cavities lined by the squamous epithelium of varying thickness with focal areas of nodular thickenings. The presence of clusters of cells with clear cytoplasm within epithelial thickenings was observed. PAS staining was negative in clear cells. The diagnosis of the GCA was established. Despite its rarity, GCA should be considered in the differential diagnosis of gingival lesions. Conservative surgical treatment proved to be effective, with no signs of recurrence.

RESUMO

Cancer cell migration involves a repertoire of signaling proteins that lead cytoskeleton reorganization as a critical step in metastatic dissemination. RhoGEFs are multidomain effectors that integrate signaling inputs to activate the molecular switches that orchestrate actin cytoskeleton reorganization. Ephexins, a group of five RhoGEFs, play oncogenic roles in invasive and metastatic cancer, leading to a mechanistic hypothesis about their function as signaling nodes assembling functional complexes that guide cancer cell migration. To identify clinically significant Ephexin signaling partners, we applied three systematic data mining strategies, based on the screening of essential Ephexins in multiple cancer cell lines and the identification of coexpressed signaling partners in the TCGA cancer patient datasets. Based on the domain architecture of encoded proteins and gene ontology criteria, we selected Ephexin signaling partners with a role in cytoskeletal reorganization and cell migration. We focused on Ephexin3/ARHGEF5, identified as an essential gene in multiple cancer cell types. Based on significant coexpression data and coessentiality, the signaling repertoire that accompanies Ephexin3 corresponded to three groups: pan-cancer, cancer-specific and coessential. To further select the Ephexin3 signaling partners likely to be relevant in clinical settings, we first identified those whose high expression was statistical linked to shorter patient survival. The resulting Ephexin3 transcriptional signatures represent significant accumulated risk, predictive of shorter survival, in 17 cancer types, including PAAD, LUAD, LGG, OSC, AML, KIRC, THYM, BLCA, LIHC and UCEC. The signaling landscape that accompanies Ephexin3 in various cancer types included the tyrosine kinase receptor MET and the tyrosine phosphatase receptor PTPRF, the serine/threonine kinases MARK2 and PAK6, the Rho GTPases RHOD, RHOF and RAC1, and the cytoskeletal regulator DIAHP1. Our findings set the basis to further explore the role of Ephexin3/ARHGEF5 as an essential effector and signaling hub in cancer cell migration.

Assuntos

Assuntos

RESUMO

BACKGROUND: Obesity is a global problem associated with several conditions, including hypertension, diabetes, arthritis and cardiovascular diseases. With the increase in the prevalence of obesity in recent years, mostly in developing countries, it is important to study its impact on various diseases, including infectious illnesses, such as Chagas disease, caused by the protozoan Trypanosoma cruzi. Considering that a diet rich in salt, sugar, and fat is associated with obesity, this study aimed to evaluate the influence of cafeteria diet (CAF)-induced obesity on immune responses in T. cruzi-infected rats. METHODS: Male Wistar Hannover rats were provided with water and food ad libitum (chow group). The CAF-fed groups received a normal rodent diet or CAF. The animals were intraperitoneally infected with 105 trypomastigote forms of the Y strain of T. cruzi present in the whole blood from a previously infected mouse. RESULTS: CAF-fed rats showed a significant increase in visceral adipose tissue weight compared to chow-fed rats. A significant reduction in CD3+ CD4+ helper splenic T cells was observed in obese-infected rats compared to non-obese-infected rats, as well as CD11b and macrophages. In addition, macrophages from obese animals displayed reduced RT1b levels compared to those from control animals. Moreover, INF-γ, an important factor in macrophage activation, was reduced in obese-infected rats compared with their counterparts. CONCLUSIONS: These results indicate that a CAF can impair the cell-mediated immune response against T. cruzi.

Assuntos

RESUMO

Calcium sensing receptor (CaSR), a class C GPCR, regulates essential secretory pathways, involving communication between endocytic and secretory Rab GTPases, via still to be fully defined molecular mechanisms. To address how communication between endocytic and secretory vesicles occurs, we hypothesized that CaSR activates endocytic Rab11A-dependent effector pathways acting upstream of Rab27B-regulated secretion. We found that Rab11A is critical to promote Rab27B-dependent secretion of chemotactic and inflammatory factors, including IL-8, CCL2/MCP-1, and IL1-ß, in response to CaSR stimulation. It also attenuates secretion of IL-6. The process is mediated by endosomal PI3-kinases, Vps34 and PI3KC2α, which promote Rab27B activation. Rab11A interacts with and activates MADD, a guanine exchange factor for Rab3, and Rab27A/B. Mechanistically, CaSR drives Rab11A-dependent coupling of recycling endosomes to secretory-vesicles via endosomal PI3K-mediated activation of a MADD/Rab27B pathway.

Assuntos

RESUMO

Metastatic cancer cells dynamically adjust their shape to adhere, invade, migrate, and expand to generate secondary tumors. Inherent to these processes is the constant assembly and disassembly of cytoskeletal supramolecular structures. The subcellular places where cytoskeletal polymers are built and reorganized are defined by the activation of Rho GTPases. These molecular switches directly respond to signaling cascades integrated by Rho guanine nucleotide exchange factors (RhoGEFs), which are sophisticated multidomain proteins that control morphological behavior of cancer and stromal cells in response to cell-cell interactions, tumor-secreted factors and actions of oncogenic proteins within the tumor microenvironment. Stromal cells, including fibroblasts, immune and endothelial cells, and even projections of neuronal cells, adjust their shapes and move into growing tumoral masses, building tumor-induced structures that eventually serve as metastatic routes. Here we review the role of RhoGEFs in metastatic cancer. They are highly diverse proteins with common catalytic modules that select among a variety of homologous Rho GTPases enabling them to load GTP, acquiring an active conformation that stimulates effectors controlling actin cytoskeleton remodeling. Therefore, due to their strategic position in oncogenic signaling cascades, and their structural diversity flanking common catalytic modules, RhoGEFs possess unique characteristics that make them conceptual targets of antimetastatic precision therapies. Preclinical proof of concept, demonstrating the antimetastatic effect of inhibiting either expression or activity of ßPix (ARHGEF7), P-Rex1, Vav1, ARHGEF17, and Dock1, among others, is emerging.

Assuntos

RESUMO

Despite advances in the treatment of heart failure, prognosis is poor, mortality high and there remains no cure. Heart failure is associated with reduced cardiac pump function, autonomic dysregulation, systemic inflammation and sleep-disordered breathing; these morbidities are exacerbated by peripheral chemoreceptor dysfunction. We reveal that in heart failure the carotid body generates spontaneous, episodic burst discharges coincident with the onset of disordered breathing in male rats. Purinergic (P2X3) receptors were upregulated two-fold in peripheral chemosensory afferents in heart failure, and when antagonized abolished these episodic discharges, normalized both peripheral chemoreceptor sensitivity and the breathing pattern, reinstated autonomic balance, improved cardiac function, and reduced both inflammation and biomarkers of cardiac failure. Aberrant ATP transmission in the carotid body triggers episodic discharges that via P2X3 receptors play a crucial role in the progression of heart failure and as such offer a distinct therapeutic angle to reverse multiple components of its pathogenesis.

Assuntos

RESUMO

ABSTRACT The gingival cyst of the adult (GCA) is a rare odontogenic cyst, consisting of 0.3% of all odontogenic cysts. This case report, based on CARE guidelines for case reports, aims to present a case of a 52-year-old female patient with a symptomatic translucent nodule in the upper left anterior gingiva, measuring approximately 6mm. Excisional biopsy was performed, and the histological examination revealed multiple cystic cavities lined by the squamous epithelium of varying thickness with focal areas of nodular thickenings. The presence of clusters of cells with clear cytoplasm within epithelial thickenings was observed. PAS staining was negative in clear cells. The diagnosis of the GCA was established. Despite its rarity, GCA should be considered in the differential diagnosis of gingival lesions. Conservative surgical treatment proved to be effective, with no signs of recurrence.

RESUMO

Assessment of ischaemia severity includes a variety of measures, such as pedal pulse palpation, the ankle/brachial index (ABI), and the toe/brachial index (TBI), but there is a lack of consensus regarding which ischaemia scale is the most effective for determining outcome prognosis. The purpose of this study is to validate the application of the ischaemia severity scale (ISS) in the effective prediction of wound healing, amputations, and mortality for diabetic foot wounds (DFW). This prospective study included 235 consecutive patients graded according to the Saint Elian Wound Score System (SEWSS). The ISS is part of this system, with patients being scored as non-ischaemic (0) or having mild (1), moderate (2), or severe (3) ischaemia. Age, diabetes duration in years, and ulcer size were found to be associated with a longer mean ischaemia of increasing severity. A trend of reduction in the pulse palpation rates (70.4%, 50%, 8.5% to 0%; p < 0.01), ABI (1.1 ± 0.1, 0.86 ± 0.3, 0.68 ± 0.2, 0.47 ± 0.2, p < 0.01), TBI average values (0.90 ± 0.35, 0.62 ± 0.52, 0.50 ± 0.33, 0.10 ± 0.42, p < 0.01), wound healing success (88.7%, 57.7%, 40.7%, 12.9%; p < 0.01), and delay in weeks (Kaplan−Meier: log-rank 44.2, p < 0.01) was observed with increasing values of the ISS (0, 1, 2, and 3). The odds ratio for adverse outcomes increased for each additional level of ischaemia severity. Thus, we demonstrate that the ISS is useful in effectively predicting adverse outcomes for DFW.

RESUMO

Systematic analysis of tumor transcriptomes, combined with deep genome sequencing and detailed clinical assessment of hundreds of patients, constitutes a powerful strategy aimed to identify potential biomarkers and therapeutic targets to guide personalized treatments. Oncogenic signaling cascades are integrated by multidomain effector proteins such as P-Rex1, a guanine nucleotide exchange factor for the Rac GTPase (RacGEF), known to promote metastatic dissemination of cancer cells. We hypothesized that patients with high P-Rex1 expression and reduced survival might be characterized by a particular set of signaling proteins co-expressed with this effector of cell migration as a central component of a putative signaling hub indicative of poor prognosis. High P-Rex1 expression correlated with reduced survival of TCGA Lower Grade Glioma (LGG) patients. Thus, guided by PREX1 expression, we searched for signaling partners of this RacGEF by applying a systematic unbiased in silico data mining strategy. We identified 30 putative signaling partners that also correlated with reduced patient survival. These included GPCRs such as CXCR3, GPR82, FZD6, as well as MAP3K1, MAP2K3, NEK8, DYRK3 and RPS6KA3 kinases, and PTPN2 and PTPN22 phosphatases, among other transcripts of signaling proteins and phospho-substrates. This PREX1 signaling hub signature correlated with increased risk of shorter survival of LGG patients from independent datasets and coincided with immune and endothelial transcriptomic signatures, indicating that myeloid infiltration and tumor angiogenesis might contribute to worsen brain tumor pathology. In conclusion, P-Rex1 and its putative signaling partners in LGG are indicative of a signaling landscape of the tumor microenvironment that correlates with poor prognosis and might guide the characterization of signaling targets leading the eventual development of immunotherapeutic strategies.