•Sarcomas are a diverse group of difficult-to-treat malignant tumors.•Histone deacetylase inhibitors are epigenetic drugs that can inhibit sarcoma growth in vitro and in vivo.•Histone deacetylase ...inhibitors can increase treatment efficiency when combined with chemotherapeutic drugs.•Histone deacetylase inhibitors represent a promising new class of compounds for the treatment of sarcomas.
Sarcomas are a rare group of malignant tumors originating from mesenchymal stem cells. Surgery, radiation and chemotherapy are currently the only standard treatments for sarcoma. However, their response rates to chemotherapy are quite low. Toxic side effects and multi-drug chemoresistance make treatment even more challenging. Therefore, better drugs to treat sarcomas are needed. Histone deacetylase inhibitors (HDAC inhibitors, HDACi, HDIs) are epigenetic modifying agents that can inhibit sarcoma growth in vitro and in vivo through a variety of pathways, including inducing tumor cell apoptosis, causing cell cycle arrest, impairing tumor invasion and preventing metastasis. Importantly, preclinical studies have revealed that HDIs can not only sensitize sarcomas to chemotherapy and radiotherapy, but also increase treatment responses when combined with other chemotherapeutic drugs. Several phase I and II clinical trials have been conducted to assess the efficacy of HDIs either as monotherapy or in combination with standard chemotherapeutic agents or targeted therapeutic drugs for sarcomas. Combination regimen for sarcomas appear to be more promising than monotherapy when using HDIs. This review summarizes our current understanding and therapeutic applications of HDIs in sarcomas.
Summary Background A non-randomised, phase 2 study showed activity and tolerability of eribulin in advanced or metastatic soft-tissue sarcoma. In this phase 3 study, we aimed to compare overall ...survival in patients with advanced or metastatic soft-tissue sarcoma who received eribulin with that in patients who received dacarbazine (an active control). Methods We did this randomised, open-label, phase 3 study across 110 study sites in 22 countries. We enrolled patients aged 18 years or older with intermediate-grade or high-grade advanced liposarcoma or leiomyosarcoma who had received at least two previous systemic regimens for advanced disease (including an anthracycline). Using an interactive voice and web response system, an independent statistician randomly assigned (1:1) patients to receive eribulin mesilate (1·4 mg/m2 intravenously on days 1 and 8) or dacarbazine (850 mg/m2 , 1000 mg/m2 , or 1200 mg/m2 dose dependent on centre and clinician intravenously on day 1) every 21 days until disease progression. Randomisation was stratified by disease type, geographical region, and number of previous regimens for advanced soft-tissue sarcoma and in blocks of six. Patients and investigators were not masked to treatment assignment. The primary endpoint was overall survival in the intention-to-treat population. The study is registered with ClinicalTrials.gov , number NCT01327885 , and is closed to recruitment, but treatment and follow-up continue. Findings Between March 10, 2011 and May 22, 2013, we randomly assigned patients to eribulin (n=228) or dacarbazine (n=224). Overall survival was significantly improved in patients assigned to eribulin compared with those assigned to dacarbazine (median 13·5 months 95% CI 10·9–15·6 vs 11·5 months 9·6–13·0; hazard ratio 0·77 95% CI 0·62–0·95; p=0·0169). Treatment-emergent adverse events occurred in 224 (99%) of 226 patients who received eribulin and 218 (97%) of 224 who received dacarbazine. Grade 3 or higher adverse events were more common in patients who received eribulin (152 67%) than in those who received dacarbazine (126 56%), as were deaths (10 4% vs 3 1%); one death (in the eribulin group) was considered treatment-related by the investigators. Interpretation Overall survival was improved in patients assigned to eribulin compared with those assigned to an active control, suggesting that eribulin could be a treatment option for advanced soft-tissue sarcoma. Funding Eisai.
microRNAs (miRNA, miR) play an important role in cancer cell growth and migration; however, the potential roles of miRNAs in osteosarcoma remain largely uncharacterized. By applying a miRNA ...microarray platform and unsupervised hierarchical clustering analysis, we found that several miRNAs have altered expression levels in osteosarcoma cell lines and tumor tissues when compared with normal human osteoblasts. Three miRNAs, miR-199a-3p, miR-127-3p, and miR-376c, were significantly decreased in osteosarcoma cell lines, whereas miR-151-3p and miR-191 were increased in osteosarcoma cell lines in comparison with osteoblasts. Transfection of precursor miR-199a-3p into osteosarcoma cell lines significantly decreased cell growth and migration, thus indicating that the inhibition effect is associated with an increase in the G(1)-phase and a decrease of the S-phase cell population. In addition, we observed decreased mTOR and Stat3 expression in miR-199a-3p transfected cells. This study provides new insights for miRNAs in osteosarcoma and suggests that miR-199a-3p may play a functional role in osteosarcoma cell growth and proliferation. Restoring miR-199a-3p's function may provide therapeutic benefits in osteosarcoma.
Summary Background Giant cell tumour of bone (GCTB) is a very rare, aggressive, and progressive osteolytic tumour for which no standard medicinal treatment or chemotherapy exists. We report interim ...safety and efficacy results from a phase 2 study of denosumab in patients with GCTB. Methods We did an international, open-label, parallel-group, phase 2 trial of patients with histologically confirmed GCTB and radiographically measurable active disease. Eligible patients were adults or skeletally mature adolescents with radiographic evidence of at least one mature long bone who were at least 12 years old and weighed at least 45 kg. We divided patients into three cohorts—those with surgically unsalvageable GCTB (cohort 1), those with salvageable GCTB whose surgery was associated with severe morbidity (cohort 2), and those who transferred from a previous study of denosumab for GCTB (cohort 3). Patients in cohorts 1 and 2 received 120 mg of subcutaneous denosumab every 4 weeks with loading doses on days 8 and 15 of the first cycle; those in cohort 3 continued the regimen from the previous study. Investigator-determined disease status and clinical benefit were assessed every 4 weeks. Our primary endpoint was the safety profile of denosumab in terms of adverse events and laboratory abnormalities. Prespecified secondary endpoints were time to disease progression in cohort 1 and the proportion of patients without any surgery at 6 months in cohort 2. Safety analyses included all patients who received at least one dose of denosumab. Efficacy analyses included all eligible patients who received at least one dose of denosumab. This study is registered with ClinicalTrials.gov , identifier NCT00680992. Findings 282 patients, including ten adolescents, were included between Sept 9, 2008, and March 25, 2011. Of the 281 patients analysable for safety, three (1%) had osteonecrosis of the jaw and 15 (5%) hypocalcaemia. The most common grade 3–4 adverse events were hypophosphataemia, which occurred in nine (3%) patients, and anaemia, back pain, and pain in extremities, each of which occurred in three patients (1%). Serious adverse events were reported in 25 (9%) patients. No treatment-related deaths were reported. On the basis of investigators' assessment of disease status, 163 of 169 (96%) analysable patients in cohort 1 had no disease progression after median follow-up of 13 months (IQR 5·8–21·0). In cohort 2, 74 of 100 (74%) analysable patients had no surgery and 16 of 26 (62%) patients who had surgery underwent a less morbid procedure than planned. Median follow-up in cohort 2 was 9·2 months (IQR 4·2–12·9). Interpretation Adverse events were consistent with the known safety profile of denosumab. Denosumab was associated with tumour responses and reduced the need for morbid surgery in patients with GCTB. Denosumab represents a new treatment option for patients with GCTB. Funding Amgen.
Chordoma is a rare malignant tumor of bone with high morbidity and mortality. Recently, aggressive pediatric poorly differentiated chordoma with SMARCB1 loss has been described. This study summarizes ...the clinicopathologic features of poorly differentiated chordoma with SMARCB1 loss in the largest series to date. A search of records between 1990-2017 at MGH identified 19 patients with poorly differentiated chordoma. Immunohistochemical stains were evaluated. Kaplan-Meier survival statistics and log-rank (Mantel Cox) tests compared survival with other subtypes. The patients (n = 19) were diagnosed at a median age of 11 years (range: 1-29). Tumors arose in the skull base and clivus (n = 10/19; 53%); cervical spine (n = 6/19; 32%); and sacrum or coccyx (n = 3/19; 16%). The clinical stage of these patients (AJCC 7e) was stage 2A (n = 7/16; 44%); stage 2B (n = 6/16; 38%); stage 4A (n = 1/16; 6%); and stage 4B (n = 2/16; 13%). The tumors were composed of sheets of epithelioid cells with nuclear pleomorphism, abundant eosinophilic cytoplasm, and increased mitoses. Tumors were positive for cytokeratin (n = 18/18; 100%) and brachyury (n = 18/18; 100%). Patients were treated with a combination of excision, radiation therapy, and chemotherapy. No difference in overall survival, progression free survival, local control time, and metastasis free survival was identified between poorly differentiated chordoma of the skull base and of the spine. Compared to other chordoma subtypes, poorly differentiated chordoma has a significantly decreased mean overall survival after stratification by site (p = 0.037). Pediatric poorly differentiated chordoma has a distinct clinical and immunohistochemical profile, with characteristic SMARCB1 loss and decreased survival compared to conventional/chondroid chordoma. Recognition of this subtype is important because these malignancies should be treated aggressively with multimodality therapy.
There are more than 70 distinct sarcomas, and this diversity complicates the development of precision-based therapeutics for these cancers. Prospective comprehensive genomic profiling could overcome ...this challenge by providing insight into sarcomas' molecular drivers. Through targeted panel sequencing of 7494 sarcomas representing 44 histologies, we identify highly recurrent and type-specific alterations that aid in diagnosis and treatment decisions. Sequencing could lead to refinement or reassignment of 10.5% of diagnoses. Nearly one-third of patients (31.7%) harbor potentially actionable alterations, including a significant proportion (2.6%) with kinase gene rearrangements; 3.9% have a tumor mutational burden ≥10 mut/Mb. We describe low frequencies of microsatellite instability (<0.3%) and a high degree of genome-wide loss of heterozygosity (15%) across sarcomas, which are not readily explained by homologous recombination deficiency (observed in 2.5% of cases). In a clinically annotated subset of 118 patients, we validate actionable genetic events as therapeutic targets. Collectively, our findings reveal the genetic landscape of human sarcomas, which may inform future development of therapeutics and improve clinical outcomes for patients with these rare cancers.
Chordomas are primary malignant tumors of the notochord that are resistant to conventional chemotherapy. Expression of programmed cell death ligand 1 (PD-L1), prevalence of tumor-infiltrating ...lymphocytes (TILs), and their clinical relevance in chordoma remain unknown. We evaluated PD-L1 expression in three chordoma cell lines and nine chordoma tissue samples by western blot. Immunohistochemical staining was performed on a chordoma tissue microarray (TMA) that contained 78 tissue specimens. We also correlated the expression of PD-L1 and TILs with clinical outcomes. PD-L1 protein expression was demonstrated to be induced by IFN-γ in both UCH1 and UCH2 cell lines. Across nine human chordoma tissue samples, PD-L1 protein was differentially expressed. 94.9% of chordoma samples showed positive PD-L1 expression in the TMA. The expression score of PD-L1 for metastatic chordoma tumors was significant higher as compared with non-metastatic chordoma tumors. Expression of PD-L1 protein significantly correlates with the presence of elevated TILs, which correlates with metastasis. In summary, our study showed high levels of PD-L1 are expressed in chordoma, which is correlated with the prevalence of TILs. The current study suggests targeting PD-L1 may be a novel immunotherapeutic strategy for chordoma clinical trials.
Osteosarcoma is the most common primary bone malignancy in children and adolescents. Herein, we investigated the role of cluster of differentiation 44 (CD44), a cell-surface glycoprotein involved in ...cell-cell interactions, cell adhesion, and migration in osteosarcoma. We constructed a human osteosarcoma tissue microarray with 114 patient tumor specimens, including tumor tissues from primary, metastatic, and recurrent stages, and determined the expression of CD44 by immunohistochemistry. Results showed that CD44 was overexpressed in metastatic and recurrent osteosarcoma as compared with primary tumors. Higher expression of CD44 was found in both patients with shorter survival and patients who exhibited unfavorable response to chemotherapy before surgical resection. Additionally, the 3'-untranslated region of CD44 mRNA was the direct target of microRNA-199a-3p (miR-199a-3p). Overexpression of miR-199a-3p significantly inhibited CD44 expression in osteosarcoma cells. miR-199a-3p is one of the most dramatically decreased miRs in osteosarcoma cells and tumor tissues as compared with normal osteoblast cells. Transfection of miR-199a-3p significantly increased the drug sensitivity through down-regulation of CD44 in osteosarcoma cells. Taken together, these results suggest that the CD44-miR-199a-3p axis plays an important role in the development of metastasis, recurrence, and drug resistance of osteosarcoma. Developing strategies to target CD44 may improve the clinical outcome of osteosarcoma.
Metastatic GI stromal tumor (GIST) is a life-threatening disease with no therapy of proven efficacy after failure of imatinib and sunitinib. Regorafenib is a structurally unique inhibitor of multiple ...cancer-associated kinases, including KIT and platelet-derived growth factor receptor (PDGFR), with broad-spectrum anticancer activity in preclinical and early-phase trials. Because KIT and PDGFR-α remain drivers of GIST after resistance to imatinib and sunitinib, we performed a multicenter single-stage phase II trial of regorafenib in patients with advanced GIST after failure of at least imatinib and sunitinib.
Patients received regorafenib orally, 160 mg daily, on days 1 to 21 of a 28-day cycle. Disease assessment was performed every two cycles per RECIST 1.1. Primary end point was clinical benefit rate (CBR), defined as objective responses (ie, complete or partial response PR as well as stable disease SD ≥ 16 weeks). Serial tumor biopsies were obtained from consenting patients whenever possible.
From February to December 2010, 34 patients were enrolled at four US centers. As of July 28, 2011, 33 patients had received at least two cycles of regorafenib (range, two to 17 cycles). CBR was 79% (95% CI, 61% to 91%). Four patients achieved PR, and 22 exhibited SD ≥ 16 weeks. Median progression-free survival was 10.0 months. The most common grade 3 toxicities were hypertension and hand-foot-skin reaction.
Regorafenib has significant activity in patients with advanced GIST after failure of both imatinib and sunitinib. A phase III trial of regorafenib versus placebo is ongoing to define more fully the safety and efficacy of regorafenib in this setting.
•Both radiation-induced and neurofibromatosis-associated MPNSTs have poorer prognosis than sporadic MPNSTs.•Complete resection of the tumor is a significant prognostic factor for MPNST.•Surgery with ...adjuvant radiotherapy is related to improved local control in patients with positive surgical margins.
Malignant peripheral nerve sheath tumors (MPNST) may be sporadic or associated with neurofibromatosis or prior radiation. MPNST may behave aggressively with a high rate of local recurrence and distant metastasis.
In an IRB approved protocol, we reviewed the clinical characteristics, treatment, and outcomes of 280 patients treated for MPNST at Massachusetts General Hospital (MGH) between 1960 and 2016.
There were 138 men and 142 women with a median age of 41 (range: 3–95) years. Tumors were classified as neurofibromatosis-associated (nfMPNST, n = 77), radiation-induced (rMPNST, n = 21), or sporadic (sMPNST, n = 182) MPNST. The median time to development of rMPNST from prior radiation was 15 years. With a median follow-up of 43.1 months, the median overall survival (OS) was 65.3 months. Older age, nfMPNST, rMPNST, increased tumor size, lymph node involvement, metastatic disease, intermediate to high grade, radiotherapy alone, and R2 resection were related to worse OS, whereas surgery with radiotherapy was associated with improved OS. Among the 251 patients without metastasis, nfMPNST, rMPNST, and increased tumor size were correlated with worse metastasis-free survival; nfMPNST, radiotherapy alone, and R1/R2 resection were associated with local recurrence, whereas surgery with adjuvant radiotherapy was related to improved local control in patients with R1/R2 resection.
Both radiation-induced and neurofibromatosis-associated MPNSTs have poorer prognosis than sporadic MPNSTs. Complete resection of the tumor is a significant prognostic factor for MPNST. The addition of radiotherapy after surgery should be considered especially when the surgical margins are positive.
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