135 research outputs found
AurkA inhibitors enhance the effects of B-RAF and MEK inhibitors in melanoma treatment
Background: Aurora kinase A (AurkA) is over-expressed in melanoma and its inhibition has been observed to limit tumor growth, suggesting a potential role in melanoma treatment.
Methods: A human melanoma cell line with the B-RAF (V600E) mutation (A375mel) was exposed to B-RAF inhibitor (GSK2118436), MEK inhibitor (GSK1120212) and AurkA inhibitor (MLN8054) as single agents or in various combinations (BRAF plus AurkA inhibitor, MEK plus AurkA inhibitor or triple combination BRAF plus MEK plus AurkA inhibitor). Cell proliferation was assessed using xCELLigence technology. Total protein extracts were examined for p53 and c-Myc protein expression by Western blot analysis. Drug anti-tumor effects were further assessed using a 3D-human melanoma skin reconstruction model, in which tissues were incubated with serum-free medium containing control, B-RAF plus MEK inhibitor, MEK plus AurkA inhibitor or the triple combination.
Results: AurkA inhibitor plus B-RAF inhibitor, AurkA inhibitor plus MEK inhibitor or triple combination had a markedly greater anti-proliferative effect on A375 (BRAFV600E) melanoma cells than single agents. In the 3D human skin model, the triple combination had a greater anti-tumor effect at the epidermal/dermal junction than control or either double combination. However, S-100 and Ki-67 positively stained spindle-shaped cells were detected in the dermal stratum, suggesting the presence of alive and proliferating melanoma cells.
Conclusions: These findings provide new prospects for melanoma research, including combined B-RAF/AurkA inhibition for B-RAF mutated melanomas and MEK/AurkA inhibitor combination for patients without B-RAF mutations. Moreover, for the first time, we have shown that a B-RAF, MEK and AurkA inhibitor triple drug combination offers increased efficacy against melanoma cell growth and might be considered as a potential treatment strategy for enhancing clinical response in melanoma. However, although this triple drug combination was more effective at the epidermal/dermal junction, the suggested presence of alive and proliferating melanoma cells in the dermal stratum could result in drug resistance and disease recurrence. Molecular characterization of these dermal cells may be critical for the development of novel therapeutic strategies
COX-2 expression positively correlates with PD-L1 expression in human melanoma cells.
Abstract
BACKGROUND:
The resistance to PD-1/PD-L1 inhibitors for the treatment of melanoma have prompted investigators to implement novel clinical trials which combine immunotherapy with different treatment modalities. Moreover is also important to investigate the mechanisms which regulate the dynamic expression of PD-L1 on tumor cells and PD-1 on T cells in order to identify predictive biomarkers of response. COX-2 is currently investigated as a major player of tumor progression in several type of malignancies including melanoma. In the present study we investigated the potential relationship between COX-2 and PD-L1 expression in melanoma.
METHODS:
Tumor samples obtained from primary melanoma lesions and not matched lymph node metastases were analyzed for both PD-L1 and COX-2 expression by IHC analysis. Status of BRAF and NRAS mutations was analyzed by sequencing and PCR. Co-localization of PD-L1 and COX-2 expression was analyzed by double fluorescence staining. Lastly the BRAFV600E A375 and NRASQ61R SK-MEL-2 melanoma cell lines were used to evaluate the effect of COX-2 inhibition by celecoxib on expression of PD-L1 in vitro.
RESULTS:
BRAFV600E/V600K and NRASQ61R/Q61L were detected in 57.8 and 8.9% of the metastatic lesions, and in 65.9 and 6.8% of the primary tumors, respectively. PD-L1 and COX-2 expression were heterogeneously expressed in both primary melanoma lesions and not matched lymph node metastases. A significantly lower number of PD-L1 negative lesions was found in primary tumors as compared to not matched metastatic lesions (P = 0.002). COX-2 expression significantly correlated with PD-L1 expression in both primary (P = 0.001) and not matched metastatic (P = 0.048) lesions. Furthermore, in melanoma tumors, cancer cells expressing a higher levels of COX-2 also co-expressed a higher level of PD-L1. Lastly, inhibition of COX-2 activity by celecoxib down-regulated the expression of PD-L1 in both BRAFV600E A375 and NRASQ61R SK-MEL-2 melanoma cell lines.
CONCLUSIONS:
COX-2 expression correlates with and modulates PD-L1 expression in melanoma cells. These findings have clinical relevance since they provide a rationale to implement novel clinical trials to test COX-2 inhibition as a potential treatment to prevent melanoma progression and immune evasion as well as to enhance the anti-tumor activity of PD-1/PD-L1 based immunotherapy for the treatment of melanoma patients with or without BRAF/NRAS mutations
Ideas in the Hispanic Caribbean in the nineteenth century: The antillanismo as emancipatory and integration ideal
En la compleja y conflictiva realidad del Caribe hispano del siglo XIX, emerge un conjunto de ideas que se organizan en torno de la voluntad de independencia, de libertad y autoafirmación política y cultural, de integración antillana y nuestroamericana. Ideas que pueden ser sintetizadas en el término antillanismo. Fueron esgrimidas en oposición al colonialismo y al imperialismo y fundamentadas desde posiciones filosóficas que abarcaron un amplio espectro, desde la ilustración al positivismo y el krausismo. Su originalidad radica en haber constituido una trama discursiva ligada dialécticamente a los acontecimientos de la situación social e histórica que buscaba comprender y transformar.In the Spanish Caribbean complex and conflicting realities of nineteenth–century,
grows a set of ideas that are organized around the desire for independence, freedom, political and cultural self–assertion and integration. These ideas can be summarized in the term antillanismo. They were put forward in opposition to colonialism and imperialism and reasoned from philosophical positions that covered a wide spectrum, from illustration to positivism and krausism. Its originality lies in having formed a discursive frame dialectically linked to the events of the socio–historical situation that sought to understand and transform.Fil: Arpini, Adriana Maria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Ciencias Humanas, Sociales y Ambientales; Argentin
Mutational concordance between primary and metastatic melanoma: a next-generation sequencing approach
Background: Cutaneous malignant melanoma (CMM) is one of the most common skin cancers worldwide. Limited
information is available in the current scientific literature on the concordance of genetic alterations between primary
and metastatic CMM. In the present study, we performed next-generation sequencing (NGS) analysis of the main
genes participating in melanoma pathogenesis and progression, among paired primary and metastatic lesions of
CMM patients, with the aim to evaluate levels of discrepancies in mutational patterns.
Methods: Paraffin-embedded tumor tissues of the paired lesions were retrieved from the archives of the institutions
participating in the study. NGS was performed using a specific multiple-gene panel constructed by the Italian
Melanoma Intergroup (IMI) to explore the mutational status of selected regions (343 amplicons; amplicon range:
125–175 bp; coverage 100%) within the main 25 genes involved in CMM pathogenesis; sequencing was performed
with the Ion Torrent PGM System.
Results: A discovery cohort encompassing 30 cases, and a validation cohort including eleven Sardinian patients with
tissue availability from both the primary and metachronous metastatic lesions were identified; the global number of
analyzed tissue specimens was 90. A total of 829 genetic non-synonymous variants were detected: 101 (12.2%) were
pathogenic/likely pathogenic, 131 (15.8%) were benign/likely benign, and the remaining 597 (72%) were uncertain/
unknown significance variants. Considering the global cohort, the consistency in pathogenic/pathogenic like mutations
was 76%. Consistency for BRAF and NRAS mutations was 95.2% and 85.7% respectively, without statistically
significant differences between the discovery and validation cohort.
Conclusions: Our study showed a high level of concordance in mutational patterns between primary and metastatic
CMM, especially when pathogenic mutations in driver genes were considered
Regulatory T cell frequency in patients with melanoma with different disease stage and course, and modulating effects of high-dose interferon-α 2b treatment
<p>Abstract</p> <p>Background</p> <p>High-dose interferon-alpha 2b (IFN-α 2b) is the only approved systemic therapy in the United States for the adjuvant treatment of melanoma. The study objective was to explore the immunomodulatory mechanism of action for IFN-α 2b by measuring serum regulatory T cell (Treg), serum transforming growth factor-β (TGF-β), interleukin (IL)-10, and autoantibody levels in patients with melanoma treated with the induction phase of the high-dose IFN-α 2b regimen.</p> <p>Methods</p> <p>Patients with melanoma received IFN-α 2b administered intravenously (20 MU/m<sup>2 </sup>each day from day 1 to day 5 for 4 consecutive weeks). Serum Treg levels were measured as whole lymphocytes in CD4<sup>+ </sup>cells using flow cytometry while TGF-β, IL-10, and autoantibody levels were measured using enzyme-linked immunosorbent assays.</p> <p>Results</p> <p>Twenty-two patients with melanoma received IFN-α 2b treatment and were evaluated for Treg levels. Before treatment, Treg levels were significantly higher in patients with melanoma when compared with data from 20 healthy subjects (<it>P </it>= 0.001; Mann-Whitney test). Although a trend for reduction of Treg levels following IFN-α 2b treatment was observed (average decrease 0.29% per week), statistical significance was not achieved. Subgroup analyses indicated higher baseline Treg levels for stage III versus IV disease (<it>P </it>= 0.082), early recurrence versus no recurrence (<it>P </it>= 0.017), deceased versus surviving patients (<it>P = </it>0.021), and preoperative neoadjuvant versus postoperative adjuvant treatment groups (not significant). No significant effects were observed on the levels of TGF-β, IL-10, and autoantibodies in patients with melanoma treated with IFN-α 2b.</p> <p>Conclusions</p> <p>Patients with melanoma in this study showed increased basal levels of Treg that may be relevant to their disease and its progression. Treg levels shifted in patients with melanoma treated with IFN-α 2b, although no firm conclusions regarding the role of Tregs as a marker of treatment response or outcome can be made at present.</p
The impact of COVID-19 pandemic on surgical residency programmes in Italy: a nationwide analysis on behalf of the Italian Polyspecialistic Young Surgeons Society (SPIGC)
Evaluation of predictive factors for i-CLARAS (intraoperative complications in laparoscopic renal and adrenal surgery): a multicentre international retrospective cohort study
The laparoscopic approach represents the standard of treatment for renal and adrenal diseases, and its use is increasing even outside referral centres. Although most procedures are routinely performed, intraoperative complications do not occur, and the rate and predictive factors of these complications have not been established. The aim of this study was to evaluate the incidence and type of intraoperative complications and to identify predictive factors in patients undergoing laparoscopic renal and adrenal surgery. This was a cohort, multicentre, international retrospective study. Patients who underwent laparoscopic renal and adrenal surgeries between April 2017 and March 2022 were included in the study. Bivariate analysis was performed using contingency tables and the χ2 test for independent samples to compare qualitative variables and the T test and Mood test for continuous variables. Multivariate analysis was performed using a logistic regression model to obtain adjusted odds ratios. A total of 2374 patients were included in the study. Intraoperative complications were reported for 8.09% of patients who underwent renal surgery, with the most common complications reported being hollow viscus and vascular complications, and for 6.75% of patients who underwent adrenal surgery, with the most common complication reported being parenchymatous viscous complications. Multivariate analysis revealed that both adrenal and renal surgery radiological preoperative factors, such as invasive features during adrenalectomy and the RENAL score during nephrectomy, are predictive factors of intraoperative complications. In contrast to existing data, surgeon experience was not associated with a reduction in the incidence of perioperative complications
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