800 research outputs found
Innovative Breakthroughs for the Treatment of Advanced and Metastatic Synovial Sarcoma
Simple Summary Synovial sarcoma (SyS) is a rare malignant soft tissue sarcoma bearing the chromosomal translocation t(X;18), which encodes the fusion oncoprotein SS18::SSX. More than 80% of the patients, mainly young in age, are initially diagnosed with localized disease with a 5-year survival rate of 70-80%. Metastatic relapse occurs in 50% of the cases. Advanced, unresectable, or metastatic disease shows a poor prognosis with a 5-year survival rate below 10%, representing an urgent clinical issue. This review will focus on: (i) current front-line therapies; (ii) alternative treatments in second line and beyond settings; and (iii) new epigenetic and immunological strategies. The improved understanding of the SyS molecular biology coupled with the recent development of innovative technologies, such as proteolysis targeting chimera (PROTAC) protein degraders or adoptive transfer of engineered immune cells, is offering new promising tools. Clinical trial results underline the need for accurate patient selection based on genetic and tumor immune microenvironment signatures. Synovial sarcoma (SyS) is a rare aggressive soft tissue sarcoma carrying the chromosomal translocation t(X;18), encoding the fusion transcript SS18::SSX. The fusion oncoprotein interacts with both BAF enhancer complexes and polycomb repressor complexes, resulting in genome-wide epigenetic perturbations and a unique altered genetic signature. Over 80% of the patients are initially diagnosed with localized disease and have a 5-year survival rate of 70-80%, but metastatic relapse occurs in 50% of the cases. Advanced, unresectable, or metastatic disease has a 5-year survival rate below 10%, representing a critical issue. This review summarizes the molecular mechanisms behind SyS and illustrates current treatments in front line, second line, and beyond settings. We analyze the use of immune check point inhibitors (ICI) in SyS that do not behave as an ICI-sensitive tumor, claiming the need for predictive genetic signatures and tumor immune microenvironment biomarkers. We highlight the clinical translation of innovative technologies, such as proteolysis targeting chimera (PROTAC) protein degraders or adoptive transfer of engineered immune cells. Adoptive cell transfer of engineered T-cell receptor cells targeting selected cancer/testis antigens has shown promising results against metastatic SyS in early clinical trials and further improvements are awaited from refinements involving immune cell engineering and tumor immune microenvironment enhancement
Uncoupling of growth inhibition and differentiation in dexamethasone-treated human rhabdomyosarcoma cells.
The effects of dexamethasone, a synthetic glucocorticoid, and of N,N-dimethylformamide on in vitro growth and differentiation and on proto-oncogene expression of human rhabdomyosarcoma cells were studied. RD/18 clone cells (derived from the embryonal rhabdomyosarcoma cell line RD) treated with 100 nM dexamethasone showed an almost complete block of differentiation: about 5% myosin-positive cells were observed after 2 weeks of culture in dexamethasone-supplemented differentiation medium, compared to 20% of untreated cultures. Dexamethasone also induced a 20-30% growth inhibition and a more flattened morphology. The treatment with N,N-dimethylformamide induced a significantly increased proportion of myosin-positive cells (reaching about 30%) and a 40% growth inhibition. Induction of differentiation inversely correlated with the levels of c-myc proto-oncogene expression: after a 2 week culture dexamethasone-treated cells showed the highest c-myc expression and N,N-dimethylformamide-treated cells the lowest. Culture conditions per se down-modulated c-erbB1 and up-regulated c-jun expression, with no relationship to the differentiation pattern. Other proto-oncogenes were not expressed (c-sis, N-myc, c-mos, c-myb) or were not modulated (c-fos, c-raf). Therefore dexamethasone and N,N-dimethylformamide, both causing a decreased growth rate, showed opposing actions on myogenic differentiation and on c-myc proto-oncogene expression of human rhabdomyosarcoma cells
Virus-like Particle (VLP) Vaccines for Cancer Immunotherapy
Cancer vaccines are increasingly being studied as a possible strategy to prevent and treat cancers. While several prophylactic vaccines for virus-caused cancers are approved and efficiently used worldwide, the development of therapeutic cancer vaccines needs to be further implemented. Virus-like particles (VLPs) are self-assembled protein structures that mimic native viruses or bacteriophages but lack the replicative material. VLP platforms are designed to display single or multiple antigens with a high-density pattern, which can trigger both cellular and humoral responses. The aim of this review is to provide a comprehensive overview of preventive VLP-based vaccines currently approved worldwide against HBV and HPV infections or under evaluation to prevent virus-caused cancers. Furthermore, preclinical and early clinical data on prophylactic and therapeutic VLP-based cancer vaccines were summarized with a focus on HER-2-positive breast cancer
LAG-3 enables DNA vaccination to persistently prevent mammary carcinogenesis in HER-2/neu transgenic BALB/c mice
Within 33 weeks of life, all 10 mammary glands of virgin BALB/c mice transgenic for the transforming rat HER-2/neu oncogene under the mammary tumor virus promoter (BALB-neuT mice) progress from atypical hyperplasia to invasive palpable carcinoma. Repeated DNA vaccination with plasmids coding for the extracellular and transmembrane domain of the protein product of rat HER-2/neu (r-p185neu) delayed tumor onset and reduced tumor multiplicity, but this protection eventually declined, and few mice were tumor free at 1 year of age. Association of plasmid vaccination with administration of soluble mouse LAG-3 (lymphocyte activation gene-3/CD223) generated by fusing the extracellular domain of murine LAG-3 to a murine IgG2a Fc portion (mLAG-3Ig) elicited a stronger and sustained protection that kept 70% of 1-year-old mice tumor free. Moreover, this combined vaccination, which was performed when multiple in situ carcinomas were already evident, extended disease-free survival and reduced carcinoma multiplicity. Inhibition of carcinogenesis was associated with markedly reduced epithelial cell proliferation and r-p185neu expression, whereas the few remaining hyperplastic foci were heavily infiltrated by reactive leukocytes. A stronger and enduring r-p185neu-specific cytotoxicity, a sustained release of IFN-γ and interleukin 4, and a marked expansion of both CD8+/CD11b+/CD28+ effector and CD8+/CD11b+/CD28- memory effector T-cell populations were induced in immunized mice. This combined vaccination also elicited a quicker and higher antibody response to r-p185neu, as well as an early antibody isotype switch. These data suggest that the appropriate costimulation provided by mLAG-3Ig enables DNA vaccination to establish an effective protection, probably by enhancing cross-presentation of the DNA coded antigen
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