A novel patient-derived immortalised cell line of myxofibrosarcoma: a tool for preclinical drugs testing and the generation of near-patient models.

BACKGROUND: Myxofibrosarcoma is a rare malignant soft tissue sarcoma characterised by multiple local recurrence and can become of higher grade with each recurrence. Consequently, myxofibrosarcoma represents a burden for patients, a challenge for clinicians, and an interesting disease to study tumour progression. Currently, few myxofibrosarcoma preclinical models are available. METHODS: In this paper, we present a spontaneously immortalised myxofibrosarcoma patient-derived cell line (MF-R 3). We performed phenotypic characterization through multiple biological assays and analyses: proliferation, clonogenic potential, anchorage-independent growth and colony formation, migration, invasion, AgNOR staining, and ultrastructural evaluation. RESULTS: MF-R 3 cells match morphologic and phenotypic characteristics of the original tumour as 2D cultures, 3D aggregates, and on the chorioallantoic membrane of chick embryos. Overall results show a clear neoplastic potential of this cell line. Finally, we tested MF-R 3 sensitivity to anthracyclines in 2D and 3D conditions finding a good response to these drugs. CONCLUSIONS: In conclusion, we established a novel patient-derived myxofibrosarcoma cell line that, together with the few others available, could serve as an important model for studying the molecular pathogenesis of myxofibrosarcoma and for testing new drugs and therapeutic strategies in diverse experimental settings.

Unveiling the Genomic Basis of Chemosensitivity in Sarcomas of the Extremities: An Integrated Approach for an Unmet Clinical Need.

Myxofibrosarcoma (MFS) and undifferentiated pleomorphic sarcoma (UPS) can be considered as a spectrum of the same disease entity, representing one of the most common adult soft tissue sarcoma (STS) of the extremities. While MFS is rarely metastasizing, it shows an extremely high rate of multiple frequent local recurrences (50-60% of cases). On the other hand, UPS is an aggressive sarcoma prone to distant recurrence, which is correlated to a poor prognosis. Differential diagnosis is challenging due to their heterogeneous morphology, with UPS remaining a diagnosis of exclusion for sarcomas with unknown differentiation lineage. Moreover, both lesions suffer from the unavailability of diagnostic and prognostic biomarkers. In this context, a genomic approach combined with pharmacological profiling could allow the identification of new predictive biomarkers that may be exploited for differential diagnosis, prognosis and targeted therapy, with the aim to improve the management of STS patients. RNA-Seq analysis identified the up-regulation of MMP13 and WNT7B in UPS and the up-regulation of AKR1C2, AKR1C3, BMP7, and SGCG in MFS, which were confirmed by in silico analyses. Moreover, we identified the down-regulation of immunoglobulin genes in patient-derived primary cultures that responded to anthracycline treatment compared to non-responder cultures. Globally, the obtained data corroborated the clinical observation of UPS as an histotype refractory to chemotherapy and the key role of the immune system in determining chemosensitivity of these lesions. Moreover, our results confirmed the validity of genomic approaches for the identification of predictive biomarkers in poorly characterized neoplasms as well as the robustness of our patient-derived primary culture models in recapitulating the chemosensitivity features of STS. Taken as a whole, this body of evidence may pave the way toward an improvement of the prognosis of these rare diseases through a treatment modulation driven by a biomarker-based patient stratification.

Temozolomide Alone or Combined with Capecitabine for the Treatment of Metastatic Neuroendocrine Neoplasia: A "Real-World" Data Analysis.

BACKGROUND: Neuroendocrine neoplasias (NENs) are a rare group of tumors with different prognosis and response to therapy. Their heterogeneity is dependent on the site of origin, morphology, and Ki67. Temozolomide (TEM) appears to be active in metastatic NENs (mNENs) but there is limited evidence about its efficacy in gastrointestinal NENs. We analyzed "real-world" data on the use of TEM alone or in association with capecitabine (CAPTEM) in patients with mNENs. PATIENTS AND METHODS: One hundred consecutive patients with advanced NENs treated with TEM or CAPTEM between 2009 and 2019 were included. A pretreatment tumor growth rate (TGR0) was calculated. Overall survival (OS), progression-free survival (PFS), tolerance, objective response rate (ORR), and disease control rate (DCR) were analyzed. A propensity score analysis and inverse probability of treatment weights for Cox regression models were used. RESULTS: TEM-based therapy was administered to 95 patients (26.3% CAPTEM and 83.7% TEM) with a median age of 59 years (range 26-85) years. ECOG performance status was 0-2. Carcinoid syndrome was reported in 12 (12.6%) patients. Twenty (21.1%) patients with grade (G) 3 neuroendocrine carcinoma (NEC) and 9 (9.4%) with G3 neuroendocrine tumors (NETs) were included in the analysis. Median PFS of the entire group was 10.4 months (95% confidence interval [CI]: 6.0-11.5). In multivariate analysis, a higher risk of progression was observed for NEC G3 patients (hazard ratio [HR] 2.70, 95% CI: 1.25-5.84) and for a TGR ≥19.55 (HR: 2.53, 95% CI: 1.45-4.40). Median OS was 23.4 months (95% CI: 17.0-29.0) and was similar in both treatment groups (23.9 vs. 20.5 months for TEM and CAPTEM, respectively, p = 0.585). In multivariate analysis, TGR ≥19.55 was associated with a higher risk of death (HR: 2.18, 95% CI: 1.16-4.11) than TGR <19.55, as was NEC G3 (HR: 2.42, 95% CI: 1.04-5.59) with respect to NETs. No differences in terms of mPFS or mOS were seen in relation to the primary site of disease. In the 86 patients evaluable for response, ORR was 44.1% and the DCR was 70.9%. Mild adverse events (grade I-II) included anemia, neutropenia, and headache. Rare cases of G 3 neutropenia and thrombocytopenia were recorded. CONCLUSIONS: TEM-based regimens are associated with a high DCR and a relatively tolerable toxicity profile in NENs of pancreatic, intestinal, and lung origin. Further investigation of these specific NETs is warranted in prospective clinical trials.

Deciphering the Genomic Landscape and Pharmacological Profile of Uncommon Entities of Adult Rhabdomyosarcomas.

Adult rhabdomyosarcoma (RMS) represents an uncommon entity with an incidence of less than 3% of all soft tissue sarcomas (STS). Consequently, the natural history and the clinical management of this disease are infrequently reported. In order to fill this gap, we investigated the molecular biology of an adult RMS case series. The expression of epithelial mesenchymal transition-related gene and chemoresistance-related gene panels were evaluated. Moreover, taking advantage of our STS translational model combining patient-derived primary culture and 3D-scaffold, the pharmacological profile of an adult head and neck sclerosing RMS was assessed. Furthermore, NGS, microsatellite instability, and in silico analyses were carried out. RT-PCR identified the upregulation of CDH1, SLUG, MMP9, RAB22a, S100P, and LAPTM4b, representing promising biomarkers for this disease. Pharmacological profiling showed the highest sensitivity with anthracycline-based regimen in both 2D and 3D culture systems. NGS analysis detected RAB3IP-HMGA2 in frame gene rearrangement and FGFR4 mutation; microsatellite instability analysis did not detect any alteration. In silico analysis confirmed the mutation of FGFR4 as a promising marker for poor prognosis and a potential therapeutic target. We report for the first time the molecular and pharmacological characterization of rare entities of adult head and neck and posterior trunk RMS. These preliminary data could shed light on this poorly understood disease.

Clinical role of filgrastim in the management of patients at risk of prolonged severe neutropenia: An evidence-based review.

BACKGROUND: Patients undergoing chemotherapy are at risk of toxicity, especially of haematological origin. Granulocyte depletion, although often underestimated, can lead to the occurrence of an event defined as febrile neutropenia (FN). Neutropenic fever syndromes are dangerous because they cause major complications in around 25%-30% of patients and have a mortality rate of up to 11%. Treatment for FN was limited to antibiotics and supportive therapies until filgrastim was approved for use in the 1990s. OBJECTIVES: The present systematic review focuses on the efficacy and safety of this haematopoietic growth factor. DATA SOURCES AND METHODS: For this review, a systematic literature search of electronic databases and references from recent reviews up to December 2018 was carried out to identify clinical trials, observational studies and case reports evaluating filgrastim efficacy and safety. English language was defined as a restriction. Published randomised controlled trials (RCTs), case reports and reviews analysing the effects of filgrastim on severe neutropenia and its limits were considered. Four review authors independently selected the studies, assessed the risk of bias and extracted study data. RESULTS: As reported in ASCO guidelines, the efficacy of filgrastim with respect to placebo or no treatment in RCTs is based on its prevention of FN. A recent meta-analysis analysed nine RCTs with 2197 patients, revealing a reduction in the incidence of FN with filgrastim (risk ratio [RR] 0.63, 95% CI 0.53-0.75). These findings were further confirmed in two observational studies. Bone pain is the most commonly reported adverse event with filgrastim, while other toxicities are associated with filgrastim efficacy and with an increased neutrophil count. KEY FINDINGS: In conclusion, our findings attest to the previous results on the efficacy and safety of filgrastim.

Management and potentialities of primary cancer cultures in preclinical and translational studies.

The use of patient-derived primary cell cultures in cancer preclinical assays has increased in recent years. The management of resected tumor tissue remains complex and a number of parameters must be respected to obtain complete sample digestion and optimal vitality yield. We provide an overview of the benefits of correct primary cell culture management using different preclinical methodologies, and describe the pros and cons of this model with respect to other kinds of samples. One important advantage is that the heterogeneity of the cell populations composing a primary culture partially reproduces the tumor microenvironment and crosstalk between malignant and healthy cells, neither of which is possible with cell lines. Moreover, the use of patient-derived specimens in innovative preclinical technologies, such as 3D systems or bioreactors, represents an important opportunity to improve the translational value of the results obtained. In vivo models could further our understanding of the crosstalk between tumor and other tissues as they enable us to observe the systemic and biological interactions of a complete organism. Although engineered mice are the most common model used in this setting, the zebrafish (Danio rerio) species has recently been recognized as an innovative experimental system. In fact, the transparent body and incomplete immune system of zebrafish embryos are especially useful for evaluating patient-derived tumor tissue interactions in healthy hosts. In conclusion, ex vivo systems represent an important tool for cancer research, but samples require correct manipulation to maximize their translational value.

Recombinant granulocyte colony-stimulating factor (rG-CSF) in the management of neutropenia induced by anthracyclines and ifosfamide in patients with soft tissue sarcomas (NEUSAR).

PURPOSE: Anthracycline and ifosfamide-based chemotherapy represents a widely used regimen both in early and advanced settings in soft tissue sarcoma (STS). Prophylaxis with granulocyte colony-stimulating factor (G-CSF) reduces the severity of chemotherapy-induced neutropenia. The aim of this study was to assess the efficacy and safety of biosimilar G-CSF in these patients. METHODS: Between 2003 and 2013, 67 patients with soft tissue tumors under epirubicin and ifosfamide (EI) treatment receiving biosimilar filgrastim (Zarzio®), originator filgrastim (Granulokine®, Neupogen®), and lenograstim (only originator Myelostim®) as primary prophylaxis for a total of 260 cycles of therapy were retrospectively analyzed. Baseline patient characteristics were summarized in a propensity score (PS). RESULTS: The incidence of febrile neutropenia (FN) was 44.0 % in biosimilar filgrastim, 40.0 % in originator filgrastim, and 45.5 % in the lenograstim groups (p = 0.935). All grade and G4 neutropenia were similar in the three groups with the same safety profile. The use of biosimilar filgrastim achieved cost savings of €225.25 over originator filgrastim and €262.00 over lenograstim. CONCLUSION: Biosimilar G-CSF was effective in preventing FN and in reducing the need for hospitalization in STS patients undergoing EI treatment. It also proved comparable to its reference products from both a clinical and cost-effective standpoint.

Tumor-Stroma Crosstalk in Bone Tissue: The Osteoclastogenic Potential of a Breast Cancer Cell Line in a Co-Culture System and the Role of EGFR Inhibition.

Although bone metastases represent a major challenge in the natural history of breast cancer (BC), the complex interactions involved have hindered the development of robust in vitro models. The aim of this work is the development of a preclinical model of cancer and bone stromal cells to mimic the bone microenvironment. We studied the effects on osteoclastogenesis of BC cells and Mesenchymal stem cells (MSC) cultured alone or in combination. We also analyzed: (a) whether the blockade of the Epithelial Growth Factor Receptor (EGFR) pathway modified their influence on monocytes towards differentiation, and (b) the efficacy of bone-targeted therapy on osteoclasts. We evaluated the osteoclastogenesis modulation of human peripheral blood monocytes (PBMC) indirectly induced by the conditioned medium (CM) of the human BC cell line SCP2, cultured singly or with MSC. Osteoclastogenesis was evaluated by TRAP analysis. The effect of the EGFR blockade was assessed by treating the cells with gefitinib, and analyzed with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and Western Blot (WB). We observed that SCP2 co-cultured with MSC increased the differentiation of PBMC. This effect was underpinned upon pre-treatment of the co-culture with gefitinib. Co-culture of SCP2 with MSC increased the expression of both the bone-related marker Receptor Activator of Nuclear Factor κB (RANK) and EGFR in BC cells. These upregulations were not affected by the EGFR blockade. The effects of the CM obtained by the cells treated with gefitinib in combination with the treatment of the preosteoclasts with the bone-targeted agents and everolimus enhanced the inhibition of the osteoclastogenesis. Finally, we developed a fully human co-culture system of BC cells and bone progenitor cells. We observed that the interaction of MSC with cancer cells induced in the latter molecular changes and a higher power of inducing osteoclastogenesis. We found that blocking EGFR signaling could be an efficacious strategy for breaking the interactions between cancer and bone cells in order to inhibit bone metastasis.

Primary Culture of Undifferentiated Pleomorphic Sarcoma: Molecular Characterization and Response to Anticancer Agents.

Undifferentiated pleomorphic sarcoma (UPS) is an aggressive mesenchymal neoplasm with no specific line of differentiation. Eribulin, a novel synthetic microtubule inhibitor, has shown anticancer activity in several tumors, including soft tissue sarcomas (STS). We investigated the molecular biology of UPS, and the mechanisms of action of this innovative microtubule-depolymerizing drug. A primary culture from a patient with UPS was established and characterized in terms of gene expression. The activity of eribulin was also compared with that of other drugs currently used for STS treatment, including trabectedin. Finally, Western blot analysis was performed to better elucidate the activity of eribulin. Our results showed an upregulation of epithelial mesenchymal transition-related genes, and a downregulation of epithelial markers. Furthermore, genes involved in chemoresistance were upregulated. Pharmacological analysis confirmed limited sensitivity to chemotherapy. Interestingly, eribulin exhibited a similar activity to that of standard treatments. Molecular analysis revealed the expression of cell cycle arrest-related and pro-apoptotic-related proteins. These findings are suggestive of aggressive behavior in UPS. Furthermore, the identification of chemoresistance-related genes could facilitate the development of innovative drugs to improve patient outcome. Overall, the results from the present study furnish a rationale for elucidating the role of eribulin for the treatment of UPS.

The Effect of Everolimus in an In Vitro Model of Triple Negative Breast Cancer and Osteoclasts.

Metastatic bone disease has a major impact on morbidity of breast cancer (BC) patients. Alterations in mTOR signaling are involved both in cancer progression and in osteoclast differentiation. The purpose of this study was to assess the role of mTOR inhibitor Everolimus (Eve) on osteoclastogenesis induced by triple negative BC cells. To this aim, we developed an in vitro human model of osteoclastogenesis from peripheral blood monocytes co-cultured with the triple negative SCP2 and the hormonal receptor positive MCF7 cell lines. Osteoclastogenesis was evaluated by TRAP staining, evaluation of F actin rings and Calcitonin Receptor expression. Eve significantly reduced differentiation induced by cancer cells and resulted more effective when evaluated in combination with Denosumab and Zoledronic Acid (Zol). Combination with Zol showed a total abrogation of osteoclast differentiation induced by the triple negative cell line, not by MCF7. Finally, we observed that Eve was active in the inhibition of the crosstalk between cancer cells and osteoclasts reproduced by our model, highlighting a new therapeutic choice for the subsetting of triple negative BC patients. We observed a difference in the response to bone-targeted therapy with respect to BC subtypes. Our model may represent a valid platform for preclinical trials on bone-targeted drugs and for the study of the interplay of BC with bone stromal cells.

Development of a Patient-Derived Xenograft (PDX) of Breast Cancer Bone Metastasis in a Zebrafish Model.

Bone metastasis is a complex process that needs to be better understood in order to help clinicians prevent and treat it. Xenografts using patient-derived material (PDX) rather than cancer cell lines are a novel approach that guarantees more clinically realistic results. A primary culture of bone metastasis derived from a 67-year-old patient with breast cancer was cultured and then injected into zebrafish (ZF) embryos to study its metastatic potential. In vivo behavior and results of gene expression analyses of the primary culture were compared with those of cancer cell lines with different metastatic potential (MCF7 and MDA-MB-231). The MCF7 cell line, which has the same hormonal receptor status as the bone metastasis primary culture, did not survive in the in vivo model. Conversely, MDA-MB-231 disseminated and colonized different parts of the ZF, including caudal hematopoietic tissues (CHT), revealing a migratory phenotype. Primary culture cells disseminated and in later stages extravasated from the vessels, engrafting into ZF tissues and reaching the CHT. Primary cell behavior reflected the clinical course of the patient's medical history. Our results underline the potential for using PDX models in bone metastasis research and outline new methods for the clinical application of this in vivo model.

Activity of Eribulin in a Primary Culture of Well-Differentiated/Dedifferentiated Adipocytic Sarcoma.

Eribulin mesylate is a novel, non-taxane, synthetic microtubule inhibitor showing antitumor activity in a wide range of tumors including soft tissue sarcomas (STS). Eribulin has been recently approved for the treatment of metastatic liposarcoma (LPS) patients previously treated with anthracyclines. This work investigated the mechanism of action of this innovative antitubulin agent in well-differentiated/dedifferentiated LPS (ALT/DDLPS) which represents one of the most common adipocytic sarcoma histotypes. A primary culture of ALT/DDLPS from a 54-year-old patient was established. The anticancer activity of eribulin on the patient-derived primary culture was assessed by MTT and tunel assays. Eribulin efficacy was compared to other drugs approved for the treatment of STS. Cell migration and morphology were examined after exposure to eribulin to better understand the drug mechanism of action. Finally, Western blot analysis of apoptosis and migration proteins was performed. The results showed that eribulin exerts its antiproliferative effect by the arrest of cell motility and induction of apoptosis. Our results highlighted the activity of eribulin in the treatment of ALT/DDLPS patients.

Combining preclinical tools and models to unravel tumor complexity: Jump into the next dimension.

Tumors are complex and heterogeneous diseases characterized by an intricate milieu and dynamically in connection with surrounding and distant tissues. In the last decades, great efforts have been made to develop novel preclinical models able to recapitulate the original features of tumors. However, the development of an in vitro functional and realistic tumor organ is still utopic and represents one of the major challenges to reproduce the architecture of the tumor ecosystem. A strategy to decrypt the whole picture and predict its behavior could be started from the validation of simplified biomimetic systems and then proceed with their integration. Variables such as the cellular and acellular composition of tumor microenvironment (TME) and its spatio-temporal distribution have to be considered in order to respect the dynamic evolution of the oncologic disease. In this perspective, we aim to explore the currently available strategies to improve and integrate in vitro and in vivo models, such as three-dimensional (3D) cultures, organoids, and zebrafish, in order to better understand the disease biology and improve the therapeutic approaches.

Novel S1R agonists counteracting NMDA excitotoxicity and oxidative stress: A step forward in the discovery of neuroprotective agents.

Sigma-1 receptor (S1R) has been considered a promising therapeutic target for several neurodegenerative diseases and S1R agonists have shown neuroprotective activity against glutamate excitotoxicity and oxidative stress. Starting from a previously identified low nanomolar S1R agonist, in this work we prepared and tested novel benzylpiperidine/benzylpiperazine-based compounds designed by applying a ring opening strategy. Among them, 4-benzyl-1-(2-phenoxyethyl)piperidine 6b (S1R Ki = 0.93 nM) and 4-benzyl-1-(3-phenoxypropyl)piperidine 8b (S1R Ki = 1.1 nM) emerged as high affinity S1R ligands and showed selectivity over S2R and N-methyl-d-aspartate receptor (NMDAR). Candidate compounds behaved as potent S1R agonists being able to enhance the neurite outgrowth induced by nerve growth factor (NGF) in PC12 cell lines. In SH-SY5Y neuroblastoma cell lines they exhibited a neuroprotective effect against rotenone- and NMDA-mediated toxic insults. The neuroprotective activity of 6b and 8b was reverted by co-treatment with an S1R antagonist, PB212. Compounds 6b and 8b were tested for cytotoxicity in-vitro against three human cancer cell lines (A549, LoVo and Panc-1) and in-vivo zebrafish model, resulting in a good efficacy/safety profile, comparable or superior to the reference drug memantine. Overall, these results encourage further preclinical investigations of 6b and 8b on in-vivo models of neurodegenerative diseases.

Modeling Myxofibrosarcoma: Where Do We Stand and What Is Missing?

Myxofibrosarcoma (MFS) is a malignant soft tissue sarcoma (STS) that originates in the body's connective tissues. It is characterized by the presence of myxoid (gel-like) and fibrous components and typically affects patients after the fifth decade of life. Considering the ongoing trend of increasing lifespans across many nations, MFS is likely to become the most common musculoskeletal sarcoma in the future. Although MFS patients have a lower risk of developing distant metastases compared with other STS cases, MFS is characterized by a high frequency of local recurrence. Notably, in 40-60% of the patients where the tumor recurs, it does so multiple times. Consequently, patients may undergo multiple local surgeries, removing the risk of potential amputation. Furthermore, because the tumor relapses generally have a higher grade, they exhibit a decreased response to radio and chemotherapy and an increased tendency to form metastases. Thus, a better understanding of MFS is required, and improved therapeutic options must be developed. Historically, preclinical models for other types of tumors have been instrumental in obtaining a better understanding of tumor development and in testing new therapeutic approaches. However, few MFS models are currently available. In this review, we will describe the MFS models available and will provide insights into the advantages and constraints of each model.

The NF-Y splicing signature controls hybrid EMT and ECM-related pathways to promote aggressiveness of colon cancer.

Aberrant splicing events are associated with colorectal cancer (CRC) and provide new opportunities for tumor diagnosis and treatment. The expression of the splice variants of NF-YA, the DNA binding subunit of the transcription factor NF-Y, is deregulated in multiple cancer types compared to healthy tissues. NF-YAs and NF-YAl isoforms differ in the transactivation domain, which may result in distinct transcriptional programs. In this study, we demonstrated that the NF-YAl transcript is higher in aggressive mesenchymal CRCs and predicts shorter patients' survival. In 2D and 3D conditions, CRC cells overexpressing NF-YAl (NF-YAlhigh) exhibit reduced cell proliferation, rapid single cell amoeboid-like migration, and form irregular spheroids with poor cell-to-cell adhesion. Compared to NF-YAshigh, NF-YAlhigh cells show changes in the transcription of genes involved in epithelial-mesenchymal transition, extracellular matrix and cell adhesion. NF-YAl and NF-YAs bind similarly to the promoter of the E-cadherin gene, but oppositely regulate its transcription. The increased metastatic potential of NF-YAlhigh cells in vivo was confirmed in zebrafish xenografts. These results suggest that the NF-YAl splice variant could be a new CRC prognostic factor and that splice-switching strategies may reduce metastatic CRC progression.

High-grade transformation of a polymorphous adenocarcinoma of the salivary gland: a case report and review of the literature.

Background: Polymorphous adenocarcinoma (PAC) represents the second most widespread neoplasm of the minor salivary glands. These tumors rarely develop a histological progression from low-grade to high-grade malignancy, named "high-grade transformation" (HGT). Only nine cases are described in literature. Case description: Here, we describe the case of a 76-year-old male patient with a PAC recurrence of the oral floor displaying HGT, and we explore the tumor cytomorphological features, genomic profiling, and the patient's clinical management. The tumor mass was characterized by poorly atypical cellular elements with vesicular nuclei and comedonecrosis foci. The growth pattern was predominantly solid, tubular, and cribriform. The lesion did not show microsatellite instability or targeted molecular alterations. The case was successfully treated with radical surgery followed by radiotherapy. Conclusion: We report for the first time the recurrence of a PAC with HGT arising in the oral floor after 20 years from the primary lesion. These preliminary data and the literature analysis enhance the knowledge of this extremely rare disease.

Growth Inhibition of Retinoblastoma Cell Line by Exosome-Mediated Transfer of miR-142-3p.

Introduction: Retinoblastoma (Rb) is the most common ocular paediatric malignancy and is caused by a mutation of the two alleles of the tumor suppressor gene, RB1. The tumor microenvironment (TME) represents a complex system whose function is not yet well defined and where microvesicles, such as exosomes, play a key role in intercellular communication. Micro-RNAs (mRNAs) have emerged as important modifiers of biological mechanisms involved in cancer and been able to regulate tumor progression. Methods: Co-culture of monocytes with retinoblastoma cell lines, showed a significant growth decrease. Given the interaction between Rb cells and monocytes, we investigated the role of the supernatant in the cross-talk between cell lines, by taking the product of the co-culture and then using it as a culture medium for Rb cells. Results: miR-142-3p showed to be particularly over-expressed both in the Rb cell line and in the medium used for their culture, comparing to control cell line and the normal supernatant, respectively. Therefore, we provided evidence that miR-142-3p is released by monocytes in the co-culture medium's exosomes and that it is subsequently up-taken by Rb cells, causing the inhibition of proliferation of Rb cell line by affecting cell cycle progression. Conclusion: This study highlights the role of exosomic miR-142-3p in the TME of Rb and identifies new molecular targets, which are able to control tumor growth aiming the development of a forward-looking miR-based strategy.

Myxofibrosarcoma landscape: diagnostic pitfalls, clinical management and future perspectives.

Myxofibrosarcoma (MFS) is a common entity of adult soft tissue sarcomas (STS) characterized by a predilection of the extremities and a high local recurrence rate. Originally classified as a myxoid variant of malignant fibrous histiocytoma, this musculoskeletal tumor has been recognized since 2002 as a distinct histotype showing a spectrum of malignant fibroblastic lesions with myxoid stroma, pleomorphism and curvilinear vessels. Currently, the molecular pathogenesis of MFS is still poorly understood and its genomic profile exhibits a complex karyotype with a number of aberrations including amplifications, deletions and loss of function. The diagnosis is challenging due to the unavailability of specific immunohistochemical markers and is based on the analysis of cytomorphologic features. The mainstay of treatment for localized disease is represented by surgical resection, with (neo)-adjuvant radio- and chemotherapy. In the metastatic setting, chemotherapy represents the backbone of treatments, however its role is still controversial and the outcome is very poor. Recent advent of genomic profiling, targeted therapies and larger enrollment of patients in translational and clinical studies, have improved the understanding of biological behavior and clinical outcome of such a disease. This review will provide an overview of current diagnostic pitfalls and clinical management of MFS. Finally, a look at future directions will be discussed.