Celecoxib as a Valuable Adjuvant in Cutaneous Melanoma Treated with Trametinib.

BACKGROUND: Melanoma patients stop responding to targeted therapies mainly due to mitogen activated protein kinase (MAPK) pathway re-activation, phosphoinositide 3 kinase/the mechanistic target of rapamycin (PI3K/mTOR) pathway activation or stromal cell influence. The future of melanoma treatment lies in combinational approaches. To address this, our in vitro study evaluated if lower concentrations of Celecoxib (IC50 in nM range) could still preserve the chemopreventive effect on melanoma cells treated with trametinib. MATERIALS AND METHODS: All experiments were conducted on SK-MEL-28 human melanoma cells and BJ human fibroblasts, used as co-culture. Co-culture cells were subjected to a celecoxib and trametinib drug combination for 72 h. We focused on the evaluation of cell death mechanisms, melanogenesis, angiogenesis, inflammation and resistance pathways. RESULTS: Low-dose celecoxib significantly enhanced the melanoma response to trametinib. The therapeutic combination reduced nuclear transcription factor (NF)-kB (p < 0.0001) and caspase-8/caspase-3 activation (p < 0.0001), inhibited microphthalmia transcription factor (MITF) and tyrosinase (p < 0.05) expression and strongly down-regulated the phosphatidylinositol-3-kinase/protein kinase B (PI3K/AKT) signaling pathway more significantly than the control or trametinib group (p < 0.0001). CONCLUSION: Low concentrations of celecoxib (IC50 in nM range) sufficed to exert antineoplastic capabilities and enhanced the therapeutic response of metastatic melanoma treated with trametinib.

Influence of mitochondrial and systemic iron levels in heart failure pathology.

Iron deficiency or overload poses an increasingly complex issue in cardiovascular disease, especially heart failure. The potential benefits and side effects of iron supplementation are still a matter of concern, even though current guidelines suggest therapeutic management of iron deficiency. In this review, we sought to examine the iron metabolism and to identify the rationale behind iron supplementation and iron chelation. Cardiovascular disease is increasingly linked with iron dysmetabolism, with an increased proportion of heart failure patients being affected by decreased plasma iron levels and in turn, by the decreased quality of life. Multiple studies have concluded on a benefit of iron administration, even if just for symptomatic relief. However, new studies field evidence for negative effects of dysregulated non-bound iron and its reactive oxygen species production, with concern to heart diseases. The molecular targets of iron usage, such as the mitochondria, are prone to deleterious effects of the polyvalent metal, added by the scarcely described processes of iron elimination. Iron supplementation and iron chelation show promise of therapeutic benefit in heart failure, with the extent and mechanisms of both prospects not being entirely understood. It may be that a state of decreased systemic and increased mitochondrial iron levels proves to be a useful frame for future advancements in understanding the interconnection of heart failure and iron metabolism.

Case Report: Aberrant Left Vertebral Artery Management in Traumatic Transection of the Aortic Isthmus.

Association of elective debranching and endovascular thoracic aortic repair (TEVAR) with aberrant left vertebral artery (AVA) revascularization and supra-aortic left carotid-subclavian bypass in post-traumatic pseudoaneurysm of the distal aortic arch are extremely rare procedures that can minimize unnecessary neurologic complications. The patient was a 42-year-old man, stable, with a post-traumatic transection of the aortic isthmus, with origin of the AVA between the left common carotid artery (LCCA) and left subclavian artery (LSA). Preoperative planning and proper sizing of the stent-grafts were evaluated by means of computed tomography angiography (CT scan) images. The patient underwent a hybrid procedure that included TEVAR with landing zone 2, covering the origin of both the AVA and LSA and concomitant supra-aortic reimplantation of the AVA in the LCCA and left carotid-subclavian bypass combined with both ligation of the AVA and LSA proximally. Postoperative arteriography images confirmed the exclusion of the aneurysm and the patency of all arch vessels, including the AVA. No endoleak was reported.

Current position of TNF-α in melanomagenesis.

Melanoma is one of the most heterogeneous and immunogenic forms of cancer. Both tumor and stroma cells synthesize many cytokines involved in rapid development and metastasis. One of these cytokines from the tumor milieu is tumor necrosis factor-alpha (TNF-α), which seems to have an intricate role in melanomagenesis. Initially, it was found that TNF-α can induce apoptosis of tumor cells through both extrinsic and intrinsic pathways, in contrast with later studies that revealed its protumoral activity. TNF-α is involved in inflammation, inducing the secretion of survival molecules like antiapoptotic proteins, proangiogenetic factors and metastasis markers. Although there are many therapeutic strategies against melanoma, the prognosis of advanced stages remains poor, due to several tumor resistance mechanisms. TNF seems to be a negative prognostic factor in melanoma surgery and correlates with chemotherapy resistance. However, high intratumoral levels of TNF-α might be beneficial for immunotherapy. Researchers may redirect their studies in the future by double activating of the proinflammatory molecule TNF-α and the immune cells in order to obtain an antitumoral response in metastatic melanoma.

Lactobacillus rhamnosus probiotic treatment modulates gut and liver inflammatory pathways in a hepatocellular carcinoma murine model. A preliminary study.

BACKGROUND AND AIMS: Hepatocellular carcinoma (HCC) is a growing global concern with an increasing incidence rate. The intestinal microbiota has been identified as a potential culprit in modulating the effects of antitumoral drugs. We aimed to assess the impact of adding Lactobacillus rhamnosus probiotic to regorafenib in mice with HCC. METHODS: Cirrhosis and HCCs were induced in 56 male Swiss mice via diethylnitrosamine injection and carbon tetrachloride administration. Mice were divided into four groups: treated with vehicle (VC), regorafenib (Rego), L. rhamnosus probiotic, and a combination of regorafenib and probiotic (Rego-Pro). After 3 weeks of treatment, liver and intestinal fragments were collected for analysis. RESULTS: Regorafenib elevated gut permeability, an effect mitigated by probiotic intervention, which exhibited a notable correlation with reduced inflammation (p < 0.01). iNOS levels were also reduced by adding the probiotic with respect to the mice treated with regorafenib only (p < 0.001). Notably, regorafenib substantially increased IL-6, TNF-a and TLR4 in intestinal fragments (p < 0.01). The administration of the probiotic effectively restored IL-6 to its initial levels (p < 0.001). CONCLUSION: Reducing systemic and intestinal inflammation by administering L. rhamnosus probiotic may alleviate tumoral resistance and systemic adverse effects.

Iron chelation alleviates multiple pathophysiological pathways in a rat model of cardiac pressure overload.

Iron dysmetabolism affects a great proportion of heart failure patients, while chronic hypertension is one of the most common risk factors for heart failure and death in industrialized countries. Serum data from reduced ejection fraction heart failure patients show a relative or absolute iron deficiency, whereas cellular myocardial analyses field equivocal data. An observed increase in organellar iron deposits was incriminated to cause reactive oxygen species formation, lipid peroxidation, and cell death. Therefore, we studied the effects of iron chelation on a rat model of cardiac hypertrophy. Suprarenal abdominal aortic constriction was achieved surgically, with a period of nine weeks to accommodate the development of chronic pressure overload. Next, deferiprone (100 mg/kg/day), a lipid-permeable iron chelator, was administered for two weeks. Pressure overload resulted in increased inflammation, fibrotic remodeling, lipid peroxidation, left ventricular hypertrophy and mitochondrial iron derangements. Deferiprone reduced cardiac inflammation, lipid peroxidation, mitochondrial iron levels, and hypertrophy, without affecting circulating iron levels or ejection fraction. In conclusion, metallic molecules may pose ambivalent effects within the cardiovascular system, with beneficial effects of iron redistribution, chiefly in the mitochondria.

Iron metabolism and cardiovascular disease: Basic to translational purviews and therapeutical approach.

Iron interactions with the cardiovascular system were proposed about half a century ago, yet a clear-cut understanding of this micronutrient and its intricacies with acute and chronic events is still lacking. In chronic heart failure, patients with decreased iron stores appear to benefit from intravenous administration of metallic formulations, whereas acute diseases (e.g., myocardial infarction, stroke) are barely studied in randomized controlled trials in humans. However, proof-of-concept studies have indicated that the dual redox characteristics of iron could be involved in atherosclerosis, necrosis, and ferroptosis. To this end, we sought to review the currently available body of literature pertaining to these temporal profiles of heart diseases, as well as the pathophysiologic mechanism by which iron enacts, underlining key points related to treatment options.

Low Doses of Celecoxib Might Promote Phenotype Switching in Cutaneous Melanoma Treated with Dabrafenib-Preliminary Study.

Background: Cutaneous melanoma is a heterogeneous tumor with a rapidly switching molecular and cellular phenotype. The invasive phenotype switching characterized by MITFlow/AXLhigh predicts early resistance to multiple targeted drugs in melanoma. Celecoxib proved to be a valuable adjuvant in cutaneous melanoma in preclinical studies. Our in vitro study evaluated for the first time whether celecoxib could prevent phenotype switching in two human melanoma cell lines treated with dabrafenib. Methods: All in vitro experiments were carried out on BRAF-V600E-positive A375 and SK-MEL-28 human melanoma cell lines, and subjected to a celecoxib and dabrafenib drug combination for 72 h. Melanoma cells were already in the MITFlow/AXLhigh end of the spectrum. Of main interest was the evaluation of the key proteins expressed in phenotype switching (TGF-ß, MITF, AXL, YAP, TAZ), as well as cell death mechanisms correlated with oxidative stress production. Results: Celecoxib significantly enhanced the apoptotic effect of dabrafenib in each melanoma cell line compared to the dabrafenib group (p < 0.0001). Even though celecoxib promoted low MITF expression, this was correlated with high receptor tyrosine kinase AXL levels in A375 and SK-MEL-28 cell lines (p < 0.0001), a positive marker for the phenotype switch to an invasive state. Conclusion: This preliminary study highlighted that celecoxib might promote MITFlow/AXLhigh expression in cutaneous melanoma treated with dabrafenib, facilitating phenotype switching in vitro. Our results need further confirmation, as this finding could represent an important limitation of celecoxib as an antineoplastic drug.

COX-2 as a potential biomarker and therapeutic target in melanoma.

With a constantly increasing incidence, cutaneous melanoma has raised the need for a better understanding of its complex microenvironment that may further guide therapeutic options. Melanoma is a model tumor in immuno-oncology. Inflammation represents an important hallmark of cancer capable of inducing and sustaining tumor development. The inflammatory process also orchestrates the adaptative immunosuppression of tumor cells that helps them to evade immune destruction. Besides its role in proliferation, angiogenesis, and apoptosis, cyclooxygenase-2 (COX-2) is a well-known promoter of immune suppression in melanoma. COX-2 inhibitors are closely involved in this condition. This review attempts to answer two controversial questions: is COX-2 a valuable prognostic factor? Among all COX-2 inhibitors, is celecoxib a suitable adjuvant in melanoma therapy?

Solid Lipid Nanoparticles: Vital Characteristics and Prospective Applications in Cancer Treatment.

Cancer nanotechnology is a new field of interdisciplinary research cutting across biology, chemistry, engineering, and medicine, aiming to lead to major advances in cancer treatment. Over the past several years, solid lipid nanoparticles (SLNs) have attracted the interest of researchers due to their ability to overcome the limitations of classic chemotherapeutics. We reviewed the most recent data on the therapeutic use of SLNs in oncology, presenting their main advantages and disadvantages, along with various production methods and different routes of administration. In accordance with these aspects, the long-term physical stability, the controlled release of the loaded drugs, and the efficient targeted delivery of drugs as methods of surpassing the pharmaceutical limitations of anticancer drugs, natural products and gene therapy have been discussed. In addition, we have also emphasized briefly the crosstalk between SLNs and the new trend in oncology, immunotherapy, as future possible antineoplastic treatment, especially in melanoma. This review highlights the potential of SLNs in providing very positive perspectives for future cancer treatment by improving the efficiency of present chemotherapy and reducing its side effects. SLNs allow targeted delivery of anticancer drugs and could improve the efficiency of current chemotherapy in neoplasia.

Combined regimen of photodynamic therapy mediated by Gallium phthalocyanine chloride and Metformin enhances anti-melanoma efficacy.

BACKGROUND: Melanoma therapy is challenging, especially in advanced cases, due to multiple developed tumor defense mechanisms. Photodynamic therapy (PDT) might represent an adjuvant treatment, because of its bimodal action: tumor destruction and immune system awakening. In this study, a combination of PDT mediated by a metal substituted phthalocyanine-Gallium phthalocyanine chloride (GaPc) and Metformin was used against melanoma. The study aimed to: (1) find the anti-melanoma efficacy of GaPc-PDT, (2) assess possible beneficial effects of Metformin addition to PDT, (3) uncover some of the mechanisms underlining cell killing and anti-angiogenic effects. METHODS: Two human lightly pigmented melanoma cell lines: WM35 and M1/15 subjected to previous Metformin exposure were treated by GaPc-PDT. Cell viability, death mechanism, cytoskeleton alterations, oxidative damage, were assessed by means of colorimetry, flowcytometry, confocal microscopy, spectrophotometry, ELISA, Western Blotting. RESULTS: GaPc proved an efficient photosensitizer. Metformin addition enhanced cell killing by mechanisms dependent on the cell line, namely apoptosis in the metastatic M1/15 and necrosis in the radial growth phase, WM35. Cell death mechanism relied on the inhibition of nuclear transcription factor (NF)-κB activation and tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) sensitization, leading to TRAIL and TNF-α induced apoptosis. Metformin diminished the anti-angiogenic effect of PDT. CONCLUSIONS: Metformin addition to GaPc-PDT increased tumor cell killing through enhanced oxidative damage and induction of proapoptotic mechanisms, but altered PDT anti-angiogenic effects. GENERAL SIGNIFICANCE: Combination of Metformin and PDT might represent a solution to enhance the efficacy, leading to a potential adjuvant role of PDT in melanoma therapy.

Photodynamic therapy of melanoma using new, synthetic porphyrins and phthalocyanines as photosensitisers - a comparative study.

UNLABELLED: Melanoma, a cancer that arises from melanocytes, is one of the most unresponsive cancers to known therapies and has a tendency to produce early metastases. Several studies showed encouraging results of the efficacy of photodynamic therapy (PDT) in melanoma, in different experimental settings in vitro and in vivo, as well as several clinical reports. AIMS: Our study focuses on testing the antimelanoma efficacy of several new, synthetic photosensitisers (PS), from two different chemical classes, respectively four porphyrins and six phthalocyanines. METHODS: These PS were tested in terms of cell toxicity and phototoxicity against a radial growth phase melanoma cell line (WM35), in vitro. Cells were exposed to different concentrations of the PS for 24h, washed, then irradiatied with red light (630 nm) 75 mJ/cm(2) for the porphyrins and 1 J/cm(2) for the phthalocyanines. Viability was measured using the MTS method. RESULTS: Two of the synthetic porphyrins, TTP and THNP, were active photosensitizers against WM35 melanoma in vitro. Phthalocyanines were effective in producing a dose dependent PDT-induced decrease in viability in a dose-dependent manner. The most efficient was Indium (III) Phthalocyanine chloride, a metal substituted phthalocyanine. CONCLUSIONS: The most efficient photosensitizers for PDT in melanoma cells were the phthalocyanines in terms of tumor cell photokilling and decreased dark toxicity.