Improved outlook for Ewing's sarcoma with combination chemotherapy (vincristine, actinomycin D and cyclophosphamide) and radiation therapy

Pharmacological targeting of P300/CBP reveals EWS::FLI1-mediated senescence evasion in Ewing sarcoma

Ewing sarcoma (ES) poses a significant therapeutic challenge due to the difficulty in targeting its main oncodriver, EWS::FLI1. We show that pharmacological targeting of the EWS::FLI1 transcriptional complex via inhibition of P300/CBP drives a global transcriptional outcome similar to direct knockdown of EWS::FLI1, and furthermore yields prognostic risk factors for ES patient outcome. We find that EWS::FLI1 upregulates LMNB1 via repetitive GGAA motif recognition and acetylation codes in ES cells and EWS::FLI1-permissive mesenchymal stem cells, which when reversed by P300 inhibition leads to senescence of ES cells. P300-inhibited senescent ES cells can then be eliminated by senolytics targeting the PI3K signaling pathway. The vulnerability of ES cells to this combination therapy suggests an appealing synergistic strategy for future therapeutic exploration.

ActO, a positive cluster-situated regulator for actinomycins biosynthesis in Streptomyces antibioticus ZS

Actinomycins are a class of cyclic lipopeptide antibiotics produced by Streptomyces, which have rich biological activities and demonstrate great potential value. Among them, actinomycin D is currently the effective drug for some malignant tumor diseases. Although the chemical properties, biological activities and biosynthesis of actinomycins have been extensively studied, the regulation of their biosynthesis remains poorly understood. Streptomyces antibioticus ZS isolated from deep-sea corals is a producer of actinomycin D and actinomycin V. Here, we reported the characterization of a cluster-situated regulator ActO in actinomycins biosynthetic gene cluster (act cluster) of S. antibioticus ZS, which belongs to LmbU family. Deletion of actO completely blocked the synthesis of actinomycins. Overexpression of actO increased the yields of actinomycin D and actinomycin V by 4.4 fold and 2.6 fold, respectively. The result of RT-qPCR showed that ActO activates the transcription of all genes in act cluster. However, no specific binding of His6-ActO to the promoters of target genes was observed after electrophoretic mobility shift assay (EMSA). These results proved that ActO serves as a positive regulator involved in the biosynthesis of actinomycins, affecting the transcription of all genes related to the synthesis of intermediates, skeleton modification and extracellular transportation of final products. Moreover, we demonstrated that overexpression of actO is a novel strategy to increase the yields of actinomycins.

(-)-Epigallocatechin-3-Gallate Attenuates the Adverse Reactions Triggered by Selenium Nanoparticles without Compromising Their Suppressing Effect on Peritoneal Carcinomatosis in Mice Bearing Hepatocarcinoma 22 Cells

Increasing evidence shows that selenium and polyphenols are two types of the most reported compounds in tumor chemoprevention due to their remarkable antitumor activity and high safety profile. The cross-talk between polyphenols and selenium is a hot research topic, and the combination of polyphenols and selenium is a valuable strategy for fighting cancer. The current work investigated the combination anti-peritoneal carcinomatosis (PC) effect of selenium nanoparticles (SeNPs) and green tea (Camellia sinensis) polyphenol (-)-epigallocatechin-3-gallate (EGCG) in mice bearing murine hepatocarcinoma 22 (H22) cells. Results showed that SeNPs alone significantly inhibited cancer cell proliferation and extended the survival time of mice bearing H22 cells. Still, the potential therapeutic efficacy is accompanied by an approximately eighty percent diarrhea rate. When EGCG was combined with SeNPs, EGCG did not affect the tumor proliferation inhibition effect but eliminated diarrhea triggered by SeNPs. In addition, both the intracellular selectively accumulated EGCG without killing effect on cancer cells and the enhanced antioxidant enzyme levels in ascites after EGCG was delivered alone by intraperitoneal injection indicated that H22 cells were insensitive to EGCG. Moreover, EGCG could prevent SeNP-caused systemic oxidative damage by enhancing serum superoxide dismutase, glutathione, and glutathione peroxidase levels in healthy mice. Overall, we found that H22 cells are insensitive to EGCG, but combining EGCG with SeNPs could protect against SeNP-triggered diarrhea without compromising the suppressing efficacy of SeNPs on PC in mice bearing H22 cells and attenuate SeNP-caused systemic toxicity in healthy mice. These results suggest that EGCG could be employed as a promising candidate for preventing the adverse reactions of chemotherapy including chemotherapy-induced diarrhea and systemic toxicity in cancer individuals.

Feasibility and Toxicity of Interval-Compressed Chemotherapy in Asian Children and Young Adults with Sarcoma

Twelve Asian patients with sarcoma received interval-compressed (ic-) chemotherapy scheduled every 14 days with a regimen of vincristine (2 mg/m²), doxorubicin (75 mg/m²), and cyclophosphamide (1200-2200 mg/m²) (VDC) alternating with a regimen of ifosfamide (9000 mg/m²) and etoposide (500 mg/m²) (IE), with filgrastim (5-10 mcg/kg/day) between cycles. Carboplatin (800 mg/m²) was added for CIC-rearranged sarcoma. The patients were treated with 129 cycles of ic-VDC/IE with a median interval of 19 days (interquartile range [IQR], 15-24 days. Median nadirs (IQR) were neutrophil count, 134 (30-396) × 10⁶/L at day 11 (10-12), recovery by day 15 (14-17) and platelet count, 35 (23-83) × 10⁹/L at day 11 (10-13), recovery by day 17 (14-21). Fever and bacteremia were observed in 36% and 8% of cycles, respectively. The diagnoses were Ewing sarcoma (6), rhabdomyosarcoma (3), myoepithelial carcinoma (1), malignant peripheral nerve sheath tumor (1), and CIC-DUX4 Sarcoma (1). Seven of the nine patients with measurable tumors responded (one CR and six PR). Interval-compressed chemotherapy is feasible in the treatment of Asian children and young adults with sarcomas.

Genetic and Histopathological Heterogeneity of Neuroblastoma and Precision Therapeutic Approaches for Extremely Unfavorable Histology Subgroups

Peripheral neuroblastic tumors (neuroblastoma, ganglioneuroblastoma and ganglioneuroma) are heterogeneous and their diverse and wide range of clinical behaviors (spontaneous regression, tumor maturation and aggressive progression) are closely associated with genetic/molecular properties of the individual tumors. The International Neuroblastoma Pathology Classification, a biologically relevant and prognostically significant morphology classification distinguishing the favorable histology (FH) and unfavorable histology (UH) groups in this disease, predicts survival probabilities of the patients with the highest hazard ratio. The recent advance of neuroblastoma research with precision medicine approaches demonstrates that tumors in the UH group are also heterogeneous and four distinct subgroups—MYC, TERT, ALT and null—are identified. Among them, the first three subgroups are collectively named extremely unfavorable histology (EUH) tumors because of their highly aggressive clinical behavior. As indicated by their names, these EUH tumors are individually defined by their potential targets detected molecularly and immunohistochemically, such as MYC-family protein overexpression, TERT overexpression and ATRX (or DAXX) loss. In the latter half on this paper, the current status of therapeutic targeting of these EUH tumors is discussed for the future development of effective treatments of the patients.

The patterns of distant metastasis and prognostic factors in patients with primary metastatic Ewing sarcoma of the bone

Background

Ewing sarcoma (ES) of bone is accounting for the second most common type of primary bone cancer in children and adolescents. However, the patterns of distant metastasis (DM) and the effect of the sites of DM on survival outcomes were not investigated.

Aims

This study aimed to investigate the patterns of DM and the prognostic factors related to outcomes in primary metastatic ES of the bone.

Methods

Patients who were diagnosed with primary metastatic ES between 2010 and 2018 were identified from the Surveillance, Epidemiology, and End Results database. Kaplan-Meier analysis, log-rank tests, and Cox proportional-hazards regression models were used for statistical analyses.

Results

We identified 277 patients in this study and 95.3% of them (n = 264) receiving chemotherapy. A total of 371 sites of DM were observed. Lung was the most common distant metastatic site (n = 182, 49.1%), followed by bone (n = 139, 37.5%), distant lymph node (n = 26, 7.0%), liver (n = 14, 3.8%), and brain (n = 10, 2.7%). Three-year cause-specific survival (CSS) was 56.1% in the entire cohort. Older age (hazard ratio [HR] 2.210, P < 0.001) and bone metastasis (HR 1.903, P = 0.002) were the independent prognostic factors associated with inferior CSS. Similar results were found in those with bone-only metastasis (n = 80) or lung-only metastasis (n = 117), which showed that patients with bone-only metastasis had an inferior CSS compared to those with metastases only to the lung (HR 1.926, P = 0.005).

Conclusions

Lung and bone are the most frequently distant metastatic sites in patients with primary metastatic ES of bone. Bone metastasis is an independent risk factor for inferior survival.

Impaired ribosome biogenesis checkpoint activation induces p53-dependent MCL-1 degradation and MYC-driven lymphoma death

MYC-driven B-cell lymphomas are addicted to increased levels of ribosome biogenesis (RiBi), offering the potential for therapeutic intervention. However, it is unclear whether inhibition of RiBi suppresses lymphomagenesis by decreasing translational capacity and/or by p53 activation mediated by the impaired RiBi checkpoint (IRBC). Here we generated Eμ-Myc lymphoma cells expressing inducible short hairpin RNAs to either ribosomal protein L7a (RPL7a) or RPL11, the latter an essential component of the IRBC. The loss of either protein reduced RiBi, protein synthesis, and cell proliferation to similar extents. However, only RPL7a depletion induced p53-mediated apoptosis through the selective proteasomal degradation of antiapoptotic MCL-1, indicating the critical role of the IRBC in this mechanism. Strikingly, low concentrations of the US Food and Drug Administration-approved anticancer RNA polymerase I inhibitor Actinomycin D (ActD) dramatically prolonged the survival of mice harboring Trp53+/+;Eμ-Myc but not Trp53-/-;Eμ-Myc lymphomas, which provides a rationale for treating MYC-driven B-cell lymphomas with ActD. Importantly, the molecular effects of ActD on Eμ-Myc cells were recapitulated in human B-cell lymphoma cell lines, highlighting the potential for ActD as a therapeutic avenue for p53 wild-type lymphoma.

Involvement of Reactive Oxygen Species in the Hepatorenal Toxicity of Actinomycin V In Vitro and In Vivo

The high toxicity of actinomycin D (Act D) severely limits its use as a first-line chemotherapeutic agent in the clinic. Actinomycin V (Act V), an analog of Act D, exhibited strong anticancer activity in our previous studies. Here, we provide evidence that Act V has less hepatorenal toxicity than Act D in vitro and in vivo, associated with the reactive oxygen species (ROS) pathway. Compared to Act D, Act V exhibited considerably stronger sensitivity for cancer cells and less toxicity to human normal liver LO-2 and human embryonic kidney 293T cells using the MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide) assay. Notably, Act V caused less damage to both the liver and kidney than Act D in vivo, indicated by organ to body weight ratios, as well as alanine aminotransferase (ALT), aspartate aminotransferase (AST), and serum creatinine (Scr) levels. Further experiments showed that the ROS pathway is involved in Act V-induced hepatorenal toxicity. Act V generates ROS and accumulates malondialdehyde (MDA), reducing levels of superoxide dismutase (SOD) and glutathione (GSH) in LO-2 and 293T cells. These findings indicate that Act V induces less hepatorenal toxicity than Act D in vitro and in vivo and merits further development as a potential therapeutic agent for the treatment of cancer.

DNA Damage-Inducing Anticancer Therapies: From Global to Precision Damage

DNA damage-inducing therapies are of tremendous value for cancer treatment and function by the direct or indirect formation of DNA lesions and subsequent inhibition of cellular proliferation. Of central importance in the cellular response to therapy-induced DNA damage is the DNA damage response (DDR), a protein network guiding both DNA damage repair and the induction of cancer-eradicating mechanisms such as apoptosis. A detailed understanding of DNA damage induction and the DDR has greatly improved our knowledge of the classical DNA damage-inducing therapies, radiotherapy and cytotoxic chemotherapy, and has paved the way for rational improvement of these treatments. Moreover, compounds targeting specific DDR proteins, selectively impairing DNA damage repair in cancer cells, form a promising novel therapy class that is now entering the clinic. In this review, we give an overview of the current state and ongoing developments, and discuss potential avenues for improvement for DNA damage-inducing therapies, with a central focus on the role of the DDR in therapy response, toxicity and resistance. Furthermore, we describe the relevance of using combination regimens containing DNA damage-inducing therapies and how they can be utilized to potentiate other anticancer strategies such as immunotherapy.

Inhibition of transcription by dactinomycin reveals a new characteristic of immunogenic cell stress

Chemotherapy still constitutes the standard of care for the treatment of most neoplastic diseases. Certain chemotherapeutics from the oncological armamentarium are able to trigger pre‐mortem stress signals that lead to immunogenic cell death (ICD), thus inducing an antitumor immune response and mediating long‐term tumor growth reduction. Here, we used an established model, built on artificial intelligence to identify, among a library of 50,000 compounds, anticancer agents that, based on their molecular descriptors, were predicted to induce ICD. This algorithm led us to the identification of dactinomycin (DACT, best known as actinomycin D), a highly potent cytotoxicant and ICD inducer that mediates immune‐dependent anticancer effects in vivo. Since DACT is commonly used as an inhibitor of DNA to RNA transcription, we investigated whether other experimentally established or algorithm‐selected, clinically employed ICD inducers would share this characteristic. As a common leitmotif, a panel of pharmacological ICD stimulators inhibited transcription and secondarily translation. These results establish the inhibition of RNA synthesis as an initial event for ICD induction.

Type II non-ribosomal peptide synthetase proteins: structure, mechanism, and protein-protein interactions

Covering: 1990 to 2019 Many medicinally-relevant compounds are derived from non-ribosomal peptide synthetase (NRPS) products. Type I NRPSs are organized into large modular complexes, while type II NRPS systems contain standalone or minimal domains that often encompass specialized tailoring enzymes that produce bioactive metabolites. Protein-protein interactions and communication between the type II biosynthetic machinery and various downstream pathways are critical for efficient metabolite production. Importantly, the architecture of type II NRPS proteins makes them ideal targets for combinatorial biosynthesis and metabolic engineering. Future investigations exploring the molecular basis or protein-protein recognition in type II NRPS pathways will guide these engineering efforts. In this review, we consolidate the broad range of NRPS systems containing type II proteins and focus on structural investigations, enzymatic mechanisms, and protein-protein interactions important to unraveling pathways that produce unique metabolites, including dehydrogenated prolines, substituted benzoic acids, substituted amino acids, and cyclopropanes.

Actinomycin D inhibits the expression of the cystine/glutamate transporter xCT via attenuation of CD133 synthesis in CD133+ HCC

Liver cancer is one of the most frequently occurring types of cancer with high mortality rate. Hepatocellular carcinoma (HCC) frequently metastasizes to lung, portal vein, and portal lymph nodes and most HCCs show strong resistance to conventional anticancer drugs. Cancer stem cells (CSCs) are considered to be responsible for resistance to therapies. Hence, recent advancements in the use of liver cancer stem cells (LCSCs) are rapidly gaining recognition as an efficient and organized means for developing antitumor agents. We aimed to use a non-target-based high-throughput screening (HTS) approach to specifically target α-fetoprotein (AFP)⁺/cluster of differentiation (CD)133⁺ HCC present in mixed populations of HCC cells and hepatocytes. Herein, we identified actinomycin D (ActD) as a potential antitumor agent that significantly inhibits activity of LCSCs without affecting the co-cultured hepatocytes. To determine the mechanism of ActD-induced tumor-specificity in LCSC, we applied various cell-based assay models in vitro. In fact, ActD significantly increased reactive oxygen species (ROS) accumulation and DNA damage in Huh7 HCC cells, but not in Fa2N-4 cells, immortalized hepatocytes. Treatment of spheroid-forming LCSCs with ActD effectively decreased spheroid formation and the CD133⁺ HCC cell population. Importantly, these ActD-mediated effects are a result of inhibition of cystine/glutamate transporter xCT expression, via attenuation of CD133 synthesis. These results indicate that ActD suppresses stemness and malignant properties in HCC cells through destabilization of xCT, by inhibition of CD133 expression in LCSCs. The effects of ActD on LCSCs provide novel therapeutic strategies for targeting cancer stem-like cells in liver cancer.

Improved Outcome in Local Ewing Sarcoma With an Intensified Pilot Treatment Protocol SCMCIE 94

This study evaluated the effect of an intensified pilot protocol, SCMCIE 94, on the outcome of Ewing sarcoma (EWS). The cohort included 121 patients with local or metastatic EWS treated at a tertiary pediatric medical center with the SCMCIE 94 (protocol 3, 1994 to 2011) or an earlier protocol (protocol 2, 1988 to 1994; protocol 1, 1985 to 1988). All protocols included 4 to 6 courses of chemotherapy, radiation, and surgery. Clinical data were collected retrospectively by chart review. Survival rates for protocol 3 were as follows: all patients-5-year event-free survival (EFS): 52.5%±5.6%, 10-year EFS: 49.3%±5.8%, 5-year overall survival (OS): 68.8%±5.3%, and 10-year OS: 51.1%±6.3%; patients with localized disease (any site)-5-year EFS: 63.5%±6.0% and 5-year OS: 77.2%±5.3%; patients with localized extremity disease-5-year EFS: 78.95%±8.3%, 10-year EFS: 68.6%±10.0%, 5-year OS: 90.7%±6.2%, and 10-year OS: 71.1%±11.2%. Protocol 3 was associated with an increase in 10-year EFS of 16% overall and 33% in patients with localized extremity disease compared with protocols 1+2, and a significant improvement in 5-year EFS and OS in patients with any localized disease (P=0.001). No survival benefit was found for metastatic disease. On multivariate analysis, protocol and metastatic disease were significantly independent prognostic factors. The intensified SCMCIE 94 protocol seems to increase survival in patients with localized but not metastatic EWS.

SCMCIE94: an intensified pilot treatment protocol known to be associated with cure in CD 56-negative non-pelvic isolated Ewing sarcoma (EWS) is also associated with no early relapses in non-metastatic extremity EWS

PURPOSE

We report the unexpected absence of early relapse (before 30 months) in 24 consecutive patients with isolated limb primary Ewing sarcoma treated with an intensified pilot protocol, SCMCIE94.

METHODS

Clinical data for the study were collected retrospectively from the patient files. The protocol included 6 courses of chemotherapy, split radiation, and limb salvage surgery. This SCMCIE94 protocol had been used in almost all the patients described in an earlier report, in whom those with non-pelvic isolated tumors and low/absent CD56 expression in Ewing sarcoma tumor cells were all long-term survivors.

RESULTS

The 5-year (10-year) event-free survival rate for the patients with isolated limb primary Ewing sarcoma was 78.95 ± 8.3% (68.6 ± 10.0%) and the overall survival rate was 90.7 ± 6.2% (71.1 ± 11.2%). There were no relapses before 30 months in any of these patients.

CONCLUSION

The intensified SCMCIE94 pilot protocol has been shown previously to cure patients with localized CD56-negative non-pelvic Ewing sarcoma. The present study shows that among all patients with localized extremity disease who were treated with this protocol, there were no cases of early relapse. Although our cohort was small, the difference in results from studies using other protocols is so striking, that it would seem reasonable to assume it is attributable to the changes made in the protocol itself rather than risk factors. Late relapses of isolated limb CD56-positive Ewing sarcoma suggest minimal residual disease warranting additional therapeutic approaches such as autologous stem cell rescue after Busulfan Melfelan.

Combining Tumor-Selective Bacterial Therapy with Salmonella typhimurium A1-R and Cancer Metabolism Targeting with Oral Recombinant Methioninase Regressed an Ewing's Sarcoma in a Patient-Derived Orthotopic Xenograft Model

BACKGROUND

Ewing's sarcoma (ES) is a recalcitrant disease in need of transformative therapeutics.

OBJECTIVES

The aim of this study was to investigate the efficacy of tumor-selective Salmonella typhimurium A1-R combined with tumor metabolism targeting with oral administration of recombinant methioninase (o-rMETase), on an ES patient-derived orthotopic xenograft (PDOX) model.

METHODS

The ES PDOX models were previously established in the right chest wall. The ES PDOX models were randomized into 5 groups when the tumor volume reached 80 mm3: G1: untreated control; G2: doxorubicin; G3: S. typhimurium A1-R; G4: o-rMETase; G5: S. typhimurium A1-R combined with o-rMETase. All mice were sacrificed on day 15. Body weight and tumor volume were assessed twice a week.

RESULTS

S. typhimurium A1-R and o-rMETase respectively suppressed tumor growth as monotherapies (p = 0.050 and p = 0.032). S. typhimurium A1-R combined with o-rMETase regressed tumor growth significantly compared to untreated group on day 15 (p < 0.032). S. typhimurium A1-R combined with o-rMETase group was significantly more effective than S. typhimurium A1-R or o-rMETase monotherapy (p = 0.032, p = 0.032).

CONCLUSIONS

The present results suggest that the combination of S. typhimurium A1-R and o-rMETase has promise to be a transformative therapy for ES.

Primary Intra-abdominal Ewing's Sarcoma in Adults: A Multimodality Imaging Spectrum

Ewing sarcoma (ES) and peripheral primitive neuroectodermal tumor are part of a spectrum of neoplastic diseases known as the ES family of tumors, which also includes extraosseous ES, peripheral primitive neuroectodermal tumor, malignant small-cell tumor of the thoracopulmonary region (Askin's tumor), and atypical ES. Although imaging features of these tumors have been previously described, extensive discussion about intra-abdominal manifestations is scarce in the literature. We present an imaging spectrum of these tumors in the abdomen and pelvis with particular attention to multimodality approach for staging and restaging.

Neutral metalloaminopeptidases APN and MetAP2 as newly discovered anticancer molecular targets of actinomycin D and its simple analogs

The potent transcription inhibitor Actinomycin D is used with several cancers. Here, we report the discovery that this naturally occurring antibiotic inhibits two human neutral aminopeptidases, the cell-surface alanine aminopeptidase and intracellular methionine aminopeptidase type 2. These metallo-containing exopeptidases participate in tumor cell expansion and motility and are targets for anticancer therapies. We show that the peptide portions of Actinomycin D and Actinomycin X₂ are not required for effective inhibition, but the loss of these regions changes the mechanism of interaction. Two structurally less complex Actinomycin D analogs containing the phenoxazone chromophores, Questiomycin A and Actinocin, appear to be competitive inhibitors of both aminopeptidases, with potencies similar to the non-competitive macrocyclic parent compound (K_i in the micromolar range). The mode of action for all four compounds and both enzymes was demonstrated by molecular modeling and docking in the corresponding active sites. This knowledge gives new perspectives to Actinomycin D's action on tumors and suggests new avenues and molecules for medical applications.

Ewing sarcoma of the head and neck: The Mayo Clinic experience

BACKGROUND

Treatment options of Ewing sarcoma of the head and neck include surgery, radiotherapy (RT), and chemoradiotherapy. However, local control can be challenging.

METHODS

We conducted a retrospective review of all patients with head and neck Ewing sarcoma treated from 1972 to 2015 at a single tertiary care hospital.

RESULTS

Seventeen patients met criteria (median 21 years, range 5-58 years; 5 women). Mean follow-up was 10.4 years (range 2.2-39 years). Tumors occurred commonly in the cervical spine (5/17), the skull (3/17), and the paranasal sinuses (3/17). A total of 14 of 17 patients underwent surgical resection, 9 with gross total resection. After multimodality therapy, the 5-year overall survival (OS) and recurrence-free survival (RFS) was 87% and 75%, respectively.

CONCLUSION

Combined multimodal treatment resulted in a 5-year OS and RFS of 87% and 75%, respectively. Aggressive surgical resection with adjuvant chemoradiotherapy should be considered. Although negative margin surgery is the goal, subtotal resection may be acceptable in the setting of adjuvant treatment.

Neoadjuvant Chemotherapy for Localized Ewing's Sarcoma of the Extremities: Preliminary Results of a Protocol Which uses Surgery (Alone or Followed by Radiotherapy) for Local Control

From June 1983 to December 1985, thirty-eight paients with localized Ewing's sarcoma of the extremities were treated with a protocol that consisted of an initial nine week period of polychemotherapy (vincristine, adriamycin and cyclophosphamide) followed by local therapy and additional chemotherapy (vincristine, adriamycin, cyclophosphamide and dactino-mycln) for one year. As local treatment all patients were offered surgery; thirty-two accepted and six refused. These six patients were locally treated with radiotherapy alone (50 Gy). In the remaining patients an amputation was performed in one case and a resection in thirty-one. In resected patients when a wide margin was achieved (24 cases) no further local treatment was performed; when it was marginal (5 cases) or intralesional (2 cases) radiotherapy at lower doses (40 Gy) followed. At mean follow-up of thirty-seven months the percentage of continuously disease-free patients was 50 % for those treated with radiotherapy, 76 % with surgery, and 85 % with surgery and radiotherapy. Eight patients developed metastatic disease and two patients had local recurrence and metastases. The local recurrences were seen in one patient locally treated with surgery and in one locally treated with radiotherapy. Nine major local complications were observed: three in patients treated with radiotherapy, five in patients treated with surgery, and one in a patient treated with surgery and radiotherapy. These results indicate that after induction chemotherapy conservative surgery is possible in almost all cases of Ewing's sarcoma of the extremities and that such treatment is better than radiotherapy alone as local therapy.

Synthesis and in vitro cytotoxicity evaluation of β-carboline-linked 2,4-thiazolidinedione hybrids: potential DNA intercalation and apoptosis-inducing studies

A series of β-carboline-linked 2,4-thiazolidinedione hybrids was synthesized and studied for their DNA affinities and cytotoxicities. The most potent compound was 19e with IC₅₀ of 0.97 ± 0.13 μM.

Manipulating Protein-Protein Interactions in Nonribosomal Peptide Synthetase Type II Peptidyl Carrier Proteins

In an effort to elucidate and engineer interactions in type II nonribosomal peptide synthetases, we analyzed biomolecular recognition between the essential peptidyl carrier proteins and adenylation domains using nuclear magnetic resonance (NMR) spectroscopy, molecular dynamics, and mutational studies. Three peptidyl carrier proteins, PigG, PltL, and RedO, in addition to their cognate adenylation domains, PigI, PltF, and RedM, were investigated for their cross-species activity. Of the three peptidyl carrier proteins, only PigG showed substantial cross-pathway activity. Characterization of the novel NMR solution structure of holo-PigG and molecular dynamics simulations of holo-PltL and holo-PigG revealed differences in structures and dynamics of these carrier proteins. NMR titration experiments revealed perturbations of the chemical shifts of the loop 1 residues of these peptidyl carrier proteins upon their interaction with the adenylation domain. These experiments revealed a key region for the protein-protein interaction. Mutational studies supported the role of loop 1 in molecular recognition, as mutations to this region of the peptidyl carrier proteins significantly modulated their activities.

The combination of temozolomide-irinotecan regresses a doxorubicin-resistant patient-derived orthotopic xenograft (PDOX) nude-mouse model of recurrent Ewing's sarcoma with a FUS-ERG fusion and CDKN2A deletion: Direction for third-line patient therapy

The aim of the present study was to determine the usefulness of a patient-derived orthotopic xenograft (PDOX) nude-mouse model of a doxorubicin-resistant metastatic Ewing’s sarcoma, with a unique combination of a FUS-ERG fusion and CDKN2A deletion, to identify effective drugs for third-line chemotherapy of the patient. Our previous study showed that cyclin-dependent kinase 4/6 (CDK4/6) and insulin-like growth factor-1 receptor (IGF-1R) inhibitors were effective on the Ewing’s sarcoma PDOX, but not doxorubicin, similar to the patient’s resistance to doxorubicin. The results of the previous PDOX study were successfully used for second-line therapy of the patiend. In the present study, the PDOX mice established with the Ewing’s sarcoma in the right chest wall were randomized into 5 groups when the tumor volume reached 60 mm³: untreated control; gemcitabine combined with docetaxel (intraperitoneal [i.p.] injection, weekly, for 2 weeks); irinotecan combined with temozolomide (irinotecan: i.p. injection; temozolomide: oral administration, daily, for 2 weeks); pazopanib (oral administration, daily, for 2 weeks); yondelis (intravenous injection, weekly, for 2 weeks). All mice were sacrificed on day 15. Body weight and tumor volume were assessed 2 times per week. Tumor weight was measured after sacrifice. Irinotecan combined with temozolomide was the most effective regimen compared to the untreated control group (p=0.022). Gemcitabine combined with docetaxel was also effective (p=0.026). Pazopanib and yondelis did not have significant efficacy compared to the untreated control (p=0.130, p=0.818). These results could be obtained within two months after the physician’s request and were used for third-line therapy of the patient.

Single-Centre Experience of Systemic Treatment with Vincristine, Ifosfamide, and Doxorubicin Alternating with Etoposide, Ifosfamide, and Cisplatin in Adult Patients with Ewing Sarcoma

The treatment of Ewing sarcoma (ES) in adult patients requires a multidisciplinary approach. Systemic therapy remains an important component of clinical management of this disease. ES is extremely rare in adult patients. Due to the rarity of the disease, no standard of care in terms of chemotherapy for the adult population exists, and the level of evidence for individual agents or some multidrug combinations is limited. Most regimens that are used in both adults and children include anthracyclines, etoposide, vincristine, cyclophosphamide, and ifosfamide. In this report, we describe our experience with the alternating use of triple combination therapies based on vincristine, ifosfamide, and doxorubicin (VIA) and an etoposide, ifosfamide, and cisplatin combination (VIP). We retrospectively evaluated the response rates, outcome, and tolerance of adult patients (n = 64) treated with VIA/VIP between 1990 and 2014. The patients included were treated with perioperative chemotherapy (53.1% neoadjuvant therapy and 17.2% adjuvant therapy) or had synchronous metastases at diagnosis (29.7%). Five-year overall survival rate was 52.2% for all patients, 72.2% for patients with localized disease, and 5.3% in patients with synchronous metastases. Overall response rate (ORR) was 37% after 2 cycles of VIA and 2 cycles of VIP. There were no patients with progressive disease (PD).

The rationale of combined radiotherapy and chemotherapy - Joint action of Castor and Pollux

This article aims to review the rationale behind the combination of radiotherapy and chemotherapy. Theoretical concepts describing the principles of the joint effects of chemoradiotherapy are reviewed. Preclinical and clinical evidence are collected and summarised demonstrating the co-operation between the two modalities which form the mainstay of the treatment of most solid tumours. Initially, the evolution of chemoradiotherapy was mostly empirically driven which is true for both, the early studies and the experimental investigations, rather than relying on scientific rationale. To date, the revised Steel's model proposes five mechanisms, spatial cooperation, cytotoxic enhancement, biological co-operation, temporary modulation and normal tissue protection to describe the interaction between radiotherapy and chemotherapy. Chemoradiotherapy has become the standard modality for most patients with locally advanced solid tumours due to better control of loco-regional disease and prolonged survival. Gradually, molecular prediction of efficacy is integrated such as MGMT status for combining temozolomide with radiotherapy in glioblastoma. As molecular targeted drugs are ready to be taken into triple combinations with chemoradiotherapy it is crucial to have a good understanding of the mechanisms of chemoradiotherapy for the rational development of future combinations.

Effect of low doses of actinomycin D on neuroblastoma cell lines

BACKGROUND

Neuroblastoma is a malignant embryonal tumor occurring in young children, consisting of undifferentiated neuroectodermal cells derived from the neural crest. Current therapies for high-risk neuroblastoma are insufficient, resulting in high mortality rates and high incidence of relapse. With the intent to find new therapies for neuroblastomas, we investigated the efficacy of low-doses of actinomycin D, which at low concentrations preferentially inhibit RNA polymerase I-dependent rRNA trasncription and therefore, ribosome biogenesis.

METHODS

Neuroblastoma cell lines with different p53 genetic background were employed to determine the response on cell viability and apoptosis of low-dose of actinomycin D. Subcutaneously-implanted SK-N-JD derived neuroblastoma tumors were used to assess the effect of low-doses of actinomycin D on tumor formation.

RESULTS

Low-dose actinomycin D treatment causes a reduction of cell viability in neuroblastoma cell lines and that this effect is stronger in cells that are wild-type for p53. MYCN overexpression contributes to enhance this effect, confirming the importance of this oncogene in ribosome biogenesis. In the wild-type SK-N-JD cell line, apoptosis was the major mechanism responsible for the reduction in viability and we demonstrate that treatment with the MDM2 inhibitor Nutlin-3, had a similar effect to that of actinomycin D. Apoptosis was also detected in p53(-/-)deficient LA1-55n cells treated with actinomycin D, however, only a small recovery of cell viability was found when apoptosis was inhibited by a pan-caspase inhibitor, suggesting that the treatment could activate an apoptosis-independent cell death pathway in these cells. We also determined whether actinomycin D could increase the efficacy of the histone deacetylase inhibitor, SAHA, which is in being used in neuroblastoma clinical trials. We show that actinomycin D synergizes with SAHA in neuroblastoma cell lines. Moreover, on subcutaneously-implanted neuroblastoma tumors derived from SK-N-JD cells, actinomycin D led to tumor regression, an effect enhanced in combination with SAHA.

CONCLUSIONS

The results presented in this work demonstrate that actinomycin D, at low concentrations, inhibits proliferation and induces cell death in vitro, as well as tumor regression in vivo. From this study, we propose that use of ribosome biogenesis inhibitors should be clinically considered as a potential therapy to treat neuroblastomas.

Whole Lung Irradiation in Adults with Metastatic Ewing Sarcoma: Practice Patterns and Implications for Treatment

Background. Whole lung irradiation (WLI) is a standard treatment component for children with metastatic Ewing Sarcoma (ES), but data on WLI for adults are sparse. Design. An email survey was sent to expert sarcoma-dedicated oncologists worldwide: An adult with excellent performance status presents with primary ES in the leg and multiple pulmonary metastases. The patient achieves complete radiographic response after chemotherapy and resection of the primary. Would you give bilateral WLI to (1) this adult patient?, (2) this patient if 20 years old (yo)?, (3) this patient if 45 yo?, or (4) this patient if 60 yo? Results. 38 experts responded, including 24 adult, 1 adolescent young adult, and 13 pediatric oncologists. 63%, 63%, 62%, and 50% of respondents offered WLI to the adult, 20-year-old, 45-year-old, and 60-year-old, respectively. Pediatric oncologists more likely endorsed WLI across all ages including the adult (P = 0.01), 20-year-old (P = 0.005), 45-year-old (P = 0.01), and 60-year-old (P = 0.08). There were no significant differences between medical and radiation oncologists or between European/Australian and American providers. Conclusions. Almost two-thirds of experts surveyed supported WLI for adults with metastatic ES up to age 45 and half supported WLI for a 60-year-old. Continued collaboration across adult and pediatric oncology is needed to define evidence-based strategies across the age spectrum.

An Oral Formulation of YK-4-279: Preclinical Efficacy and Acquired Resistance Patterns in Ewing Sarcoma

Ewing sarcoma is a transcription factor-mediated pediatric bone tumor caused by a chromosomal translocation of the EWSR1 gene and one of several genes in the ETS family of transcription factors, typically FLI1 or ERG. Full activity of the resulting oncogenic fusion protein occurs only after binding RNA helicase A (RHA), and novel biologically targeted small molecules designed to interfere with that interaction have shown early promise in the preclinical setting. Herein, we demonstrate marked preclinical antineoplastic activity of an orally bioavailable formulation of YK-4-279 and identify mechanisms of acquired chemotherapy resistance that may be exploited to induce collateral sensitivity. Daily enteral administration of YK-4-279 led to significant delay in Ewing sarcoma tumor growth within a murine model. In advance of anticipated early-phase human clinical trials, we investigated both de novo and acquired mechanism(s) by which Ewing sarcoma cells evade YK-4-279-mediated cell death. Drug-resistant clones, formed by chronic in vitro exposure to steadily increased levels of YK-4-279, overexpressed c-Kit, cyclin D1, pStat3(Y705), and PKC isoforms. Interestingly, cross-resistance to imatinib and enzastaurin (selective inhibitors of c-Kit and PKC-β, respectively), was observed and the use of YK-4-279 with enzastaurin in vitro led to marked drug synergy, suggesting a potential role for combination therapies in the future. By advancing an oral formulation of YK-4-279 and identifying prominent mechanisms of resistance, this preclinical research takes us one step closer to a shared goal of curing adolescents and young adults afflicted by Ewing sarcoma.

Radiation for bone metastases in Ewing sarcoma and rhabdomyosarcoma

BACKGROUND

The role, optimal dose, and efficacy of radiotherapy (RT) for the treatment of bone metastases in rhabdomyosarcoma (RMS) and Ewing sarcoma (ES) are unclear.

PROCEDURE

All patients with ES or RMS who received RT for bone metastases with curative intent during frontline therapy at Memorial Sloan Kettering Cancer Center (MSKCC) between 1995 and 2013 were reviewed. Among the 30 patients (8 RMS and 22 ES), 49 bone metastases were irradiated.

RESULTS

Median biologically effective dose (BED) was 42.4 Gy (range, 34.9-59.7) for RMS and 50.7 Gy (range, 31.3-65.8) for ES. Tumor recurrence occurred in six of 49 irradiated bone metastases. Cumulative incidence of local failure at a treated metastatic site was 6.6% at 1 year and 9.0% at 3 years. Dose, fractionation, and RT technique did not impact local control at an irradiated site. The presence of >5 bone metastases was associated with worse local control at an irradiated site (P = 0.07). The 3-year EFS was 33% in RMS and 16% in ES.

CONCLUSIONS

RT appears to be an effective modality of local control for bone metastases in ES and RMS. Local control at sites of metastatic bone irradiation is similar to local control at the primary site after definitive RT. Doses in the biologic range prescribed for the definitive treatment of primary disease should be used for metastatic sites of disease.

Prognostic factors for survival in patients with Ewing's sarcoma using the surveillance, epidemiology, and end results (SEER) program database

BACKGROUND

The current study aims to determine cause-specific survival in patients with Ewing's sarcoma while reporting clinical risk factors for survival.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) Program database was used to identify patients with osseous Ewing's sarcoma from 1991 to 2010. Patient, tumor, and socioeconomic variables were analyzed to determine prognostic factors for survival.

RESULTS

There were 1163 patients with Ewing's sarcoma identified in the SEER Program database. The 10-year cause-specific survival for patients with non-metastatic disease at diagnosis was 66.8% and 28.1% for patients with metastatic disease. Black patients demonstrated reduced survival at 10 years with an increased frequency of metastatic disease at diagnosis as compared to patients of other race, while Hispanic patients more frequently presented with tumor size>10cm. Univariate analysis revealed that metastatic disease at presentation, tumor size>10cm, axial tumor location, patient age≥20 years, black race, and male sex were associated with decreased cause-specific survival at 10 years. Metastatic disease at presentation, axial tumor location, tumor size>10cm, and age≥20 years remained significant in the multivariate analysis.

CONCLUSIONS

Patients with Ewing's sarcoma have decreased cause-specific survival at 10 years when metastatic at presentation, axial tumor location, tumor size>10cm, and patient age≥20 years.

In vitro antimicrobial, antioxidant and cytotoxic properties of Streptomyces lavendulae strain SCA5

BACKGROUND

Actinomycetes are Gram-positive, often filamentous, bacteria known for their unsurpassed capacity for the production of secondary metabolites with diverse biological activities. The aim of the present study was to evaluate the antimicrobial, cytotoxic and antioxidant properties of Streptomyces lavendulae strain SCA5.

RESULTS

The ethyl acetate extract of SCA5 broth (EA-SCA5) showed antimicrobial activity with MIC value of 31.25 μg/ml. EA-SCA5 showed good antioxidant potential by scavenging 2, 2-diphenyl-picrylhydrazyl (DPPH) (IC50 507.61 ± 0.66 μg/ml), hydroxyl radical (IC50 617.84 ± 0.57 μg/ml), nitric oxide (IC50 730.92 ± 0.81 μg/ml) and superoxide anion radical (IC50 864.71 ± 1.15 μg/ml). The EA-SCA5 also showed strong suppressive effect on rat liver lipid peroxidation (IC50 838.83 ± 1.18 μg/ml). The total phenolic content of SCA5 was 577.12 mg of GAE equivalents/gram extract. EA-SCA5 exhibited cytotoxic activity on A549 adenocarcinoma lung cancer cell line. It showed 84.9% activity at 500 μg/ml with IC50 value of 200 μg/ml. The gas chromatography mass spectrometry (GC-MS) analysis revealed the presence of one major bioactive compound actinomycin C2.

CONCLUSIONS

The results of this study indicate that the EA-SCA5 could be probed further for isolating some medically useful compounds.

Whole lung irradiation for adults with pulmonary metastases from Ewing sarcoma

PURPOSE

To evaluate feasibility and patterns of failure in adult patients with Ewing sarcoma (ES) treated with whole lung irradiation (WLI) for pulmonary metastases.

METHODS AND MATERIALS

Retrospective review of all ES patients treated at age 18 or older with 12-15 Gy WLI for pulmonary metastases at a single institution between 1990 and 2014. Twenty-six patients met the study criteria.

RESULTS

The median age at WLI was 23 years (range, 18-40). The median follow-up time of the surviving patients was 3.8 years (range, 1.0-9.6). The 3-year cumulative incidence of pulmonary relapse (PR) was 55%, with a 3-year cumulative incidence of PR as the site of first relapse of 42%. The 3-year event-free survival (EFS) and overall survival (OS) were 38 and 45%, respectively. Patients with exclusively pulmonary metastases had better outcomes than did those with extrapulmonary metastases: the 3-year PR was 45% in those with exclusively lung metastases versus 76% in those with extrapulmonary metastases (P=.01); the 3-year EFS was 49% versus 14% (P=.003); and the 3-year OS was 61% versus 13% (P=.009). Smoking status was a significant prognostic factor for EFS: the 3-year EFS was 61% in nonsmokers versus 11% in smokers (P=.04). Two patients experienced herpes zoster in the radiation field 6 and 12 weeks after radiation. No patients experienced pneumonitis or cardiac toxicity, and no significant acute or late sequelae were observed among the survivors.

CONCLUSION

WLI in adult patients with ES and lung metastases is well tolerated and is associated with freedom from PR of 45% at 3 years. Given its acceptable toxicity and potential therapeutic effect, WLI for pulmonary metastases in ES should be considered for adults, as it is in pediatric patients. All patients should be advised to quit smoking before receiving WLI.

Outcome for children with metastatic solid tumors over the last four decades

Background

Outcomes for pediatric solid tumors have significantly improved over the last 30 years. However, much of this improvement is due to improved outcome for patients with localized disease. Here we evaluate overall survival (OS) for pediatric patients with metastatic disease over the last 40 years.

Procedure

The United States Surveillance, Epidemiology, and End Results (SEER) database was used to conduct this study. Patients diagnosed between 0 and 18 years of age with metastatic Ewings sarcoma, neuroblastoma, osteosarcoma, rhabdomyosarcoma or Wilms tumor were included in the analysis.

Results

3,009 patients diagnosed between 1973–2010 met inclusion criteria for analysis. OS at 10 years for patients diagnosed between 1973–1979, 1980–1989, 1990–1999 and 2000–2010 was 28.3%, 37.2%, 44.7% and 49.3%, respectively (p<0.001). For patients diagnosed between 2000–2010, 10-year OS for patients with Ewing sarcoma, neuroblastoma, osteosarcoma, rhabdomyosarcoma and Wilms tumor was 30.6%, 54.4%, 29.3%, 27.5%, and 76.6%, respectively, as compared to 13.8%, 25.1%, 13.6%, 17.9% and 57.1%, respectively, for patients diagnosed between 1973–1979. OS for neuroblastoma significantly increased with each decade. For patients with osteosarcoma and Ewing sarcoma, there was no improvement in OS over the last two decades. There was no improvement in outcome for patients with rhabdomyosarcoma or Wilms tumor over the last 30 years.

Conclusions

OS for pediatric patients with metastatic solid tumors has significantly improved since the 1970s. However, outcome has changed little for some malignancies in the last 20–30 years. These data underscore the importance of continued collaboration and studies to improve outcome for these patients.

p53 -Dependent and -Independent Nucleolar Stress Responses

The nucleolus has emerged as a cellular stress sensor and key regulator of p53-dependent and -independent stress responses. A variety of abnormal metabolic conditions, cytotoxic compounds, and physical insults induce alterations in nucleolar structure and function, a situation known as nucleolar or ribosomal stress. Ribosomal proteins, including RPL11 and RPL5, become increasingly bound to the p53 regulatory protein MDM2 following nucleolar stress. Ribosomal protein binding to MDM2 blocks its E3 ligase function leading to stabilization and activation of p53. In this review we focus on a number of novel regulators of the RPL5/RPL11-MDM2-p53 complex including PICT1 (GLTSCR2), MYBBP1A, PML and NEDD8. p53-independent pathways mediating the nucleolar stress response are also emerging and in particular the negative control that RPL11 exerts on Myc oncoprotein is of importance, given the role of Myc as a master regulator of ribosome biogenesis. We also briefly discuss the potential of chemotherapeutic drugs that specifically target RNA polymerase I to induce nucleolar stress.

Ewing sarcoma: clinical state-of-the-art

Ewing sarcoma, a rare malignancy of childhood and adolescence, has become a model of advances in diagnosis, treatment, and outcome through long-standing research efforts in multinational clinical trials. With modern multimodal regimens consisting of local surgery and/or radiotherapy plus intensive systemic chemotherapy, survival can be achieved for ≈ 70% of patients with localized disease. However, in the last decade, improvement in survival curves has slowed down. Also, a relapse rate of ≈ 30% remains unacceptable, since salvage strategies for Ewing sarcoma recurrence are discouraging and prognosis is unfavorable in most cases. Metastatic disease at diagnosis poses a similar challenge, since even if remission is achieved, relapse frequently occurs despite the most intensive treatment. Urgently needed, novel biology-driven treatment options are now beginning to emerge on the horizon, but have not yet reached the standard of care. An overview of the current clinical state-of-the-art is provided in this article.

Towards novel radiosensitizing agents: the role of cytosolic PLA2α in combined modality cancer therapy

The radioresistant nature of some tumors serves as an obstacle to curative therapy for several poor-prognosis malignancies. The radiosensitivity of a cancer is dependent not only on the intrinsic ability of tumor cells to recover from radiation-induced damage, but also the ability of stromal elements (e.g., vasculature) in the tumor microenvironment to survive and continue proliferating in the face of ionizing radiation. In this regard, it is important to understand the initial events activating radiation-induced signal transduction pathways. Among these events is the activation of cytosolic phospholipase A2 α and the subsequent production of the lipid second messengers. These events occur within minutes following exposure to ionizing radiation, and have been shown to enhance cell viability through a number of prosurvival signaling pathways. Furthermore, inhibition of cytosolic phospholipase A2 α has now been shown to reduce the viability of endothelial cells in culture after exposure to ionizing radiation, as well as slowing the growth of tumors in animal models of cancer.

Efficacy of Proton Beam Therapy in the Treatment of Ewing's Sarcoma of the Paranasal Sinuses and Anterior Skull Base

Ewing's sarcoma involving the sinonasal cavity and anterior skull base is very rare. The purpose of this article is to present our experience with two such cases, which were both treated with combined chemotherapy and proton beam radiation therapy. The patients were selected from a retrospective medical record analysis that was conducted of all patients who were diagnosed with Ewing's sarcoma of the sinonasal cavity at the Massachusetts Eye & Ear Infirmary/Massachusetts General Hospital Cranial Base Center from 2004 to 2008. One of the patients underwent pretreatment endoscopic subtotal resection to facilitate proton beam radiation therapy. Response to treatment was assessed, post-treatment endoscopic biopsies were performed to assure eradication of disease, and treatment complications were recorded. Both patients completed chemotherapy and proton beam radiation therapy without complication. One patient completed treatment in December 2006 and remains disease free. The second patient completed treatment in March 2007 and remains disease free. Both patients developed headaches accompanied by frontal sinus opacification after treatment that required endoscopic drainage. After endoscopic drainage, the opacification and symptoms resolved.

The clinical value of flow cytometric DNA content analysis in patients with soft tissue sarcomas

Purpose. The purpose of this study was to evaluate: (1) the correlation between grade and ploidy or S-phase fraction (SPF), (2) the prognostic value of DNA flow cytometric study in soft tissue sarcomas.

Patients /Methods. In all, 47 tissue samples from soft tissue sarcoma patients, surgically treated in the same center, were included. Flow cytometric analyses were performed according to a modified version of the original method of Hedley et al.

Results. DNA ploidy status could be determined in 44 samples out of 47 (success rate 94%). Of these 44, S-phase fraction could be calculated in 34 samples (77%). In the study group as a whole, aneuploidy was significantly correlated with high grade. Survival analyses were carried out in 21 patients with soft tissue sarcoma, all surgically treated in the same center, without chemotherapy or radiotherapy. In univariate analyses, DNA ploidy was found to be a significant factor for overall survival (OAS) and metastasis-free survival MFS. Mean OAS for aneuploid tumors and diploid tumors were 35 and 65 months (p=0.034), and mean MFS 23 and 61 months, respectively (p=0.005) .

Discussion.There is a relation between histological grade and ploidy in soft tissue sarcomas. It appears that low-grade tumors are generally diploid, whereas high-grade tumors tend to be aneuploid. In a subgroup of patients treated only with surgery, DNA ploidy was found to be an important factor for predicting OAS and MFS.

Prognostic significance of HLA class I expression in Ewing's sarcoma family of tumors

BACKGROUND

Ewing's sarcoma family of tumors (ESFT) is one of the most malignant groups of tumors in young people. Human leukocyte antigen (HLA) class I displays endogenously processed peptides to CD8+ T lymphocytes and has a key role for host immune surveillance. In ESFT, the investigation concerning both HLA class I expression and T-cell infiltration has yet to be reported.

METHODS

Biopsy specimens from 28 ESFT patients were evaluated by immunohistochemistry with the anti-HLA class I monoclonal antibody (mAb) EMR8-5 and anti-CD8 mAb, respectively.

RESULTS

Expression of HLA class I was negative in 10 tumors and down-regulated in 22 tumors. The status of CD8+ T cell infiltration was closely associated with the expression levels of HLA class I. ESFT patients with down-regulated or negative expression of HLA class I showed significantly poorer survival than the rest of the patients.

CONCLUSIONS

Our results suggested that CD8+ T cell-mediated immune response restricted by HLA class I might play an important role in immune surveillance of ESFT, and we revealed for the first time that the status of HLA class I expression affects the survival of the patients with ESFT.

Targeting inflammatory pathways for tumor radiosensitization

Although radiation therapy (RT) is an integral component of treatment of patients with many types of cancer, inherent and/or acquired resistance to the cytotoxic effects of RT is increasingly recognized as a significant impediment to effective cancer treatment. Inherent resistance is mediated by constitutively activated oncogenic, proliferative and anti-apoptotic proteins/pathways whereas acquired resistance refers to transient induction of proteins/pathways following radiation exposure. To realize the full potential of RT, it is essential to understand the signaling pathways that mediate inducible radiation resistance, a poorly characterized phenomenon, and identify druggable targets for radiosensitization. Ionizing radiation induces a multilayered signaling response in mammalian cells by activating many pro-survival pathways that converge to transiently activate a few important transcription factors (TFs), including nuclear factor kappa B (NF-κB) and signal transducers and activators of transcription (STATs), the central mediators of inflammatory and carcinogenic signaling. Together, these TFs activate a wide spectrum of pro-survival genes regulating inflammation, anti-apoptosis, invasion and angiogenesis pathways, which confer tumor cell radioresistance. Equally, radiation-induced activation of pro-inflammatory cytokine network (including interleukin (IL)-1β, IL-6 and tumor necrosis factor-α) has been shown to mediate symptom burden (pain, fatigue, local inflammation) in cancer patients. Thus, targeting radiation-induced inflammatory pathways may exert a dual effect of accentuating the tumor radioresponse and reducing normal tissue side-effects, thereby increasing the therapeutic window of cancer treatment. We review recent data demonstrating the pivotal role played by inflammatory pathways in cancer progression and modulation of radiation response.

Ewing's sarcoma

Progress in the treatment of Ewing's sarcoma, the second most common bone tumour in children and adolescents, has improved survival from about 10% in the period before chemotherapy was introduced to about 75% today for patients with localised tumours. However, patients with metastases still fare badly, and the therapy carries short-term and long-term toxicities. Multidisciplinary care is indispensable for these patients. Molecular techniques and new imaging modalities are affecting the diagnosis and classification of patients with Ewing's sarcoma. Cooperative group studies have led to chemotherapy regimens using the same drugs (vincristine, doxorubicin, cyclophosphamide, ifosfamide, and etoposide), although the exact regimens differ in Europe and North America. The EWS-ETS family of gene fusions and their downstream effects in Ewing's sarcomas provide opportunities for new approaches to treatment. These include the inhibition of the fusion gene or its protein product, and pathways related to IGF1 and mTOR. Inhibition of tyrosine kinases, exploitation of non-apoptotic cell death, and interference with angiogenesis are promising new approaches. With many new approaches and relatively few patients, it will be challenging to integrate new and established treatments through clinical trials.

Ewing sarcoma demonstrates racial disparities in incidence-related and sex-related differences in outcome: an analysis of 1631 cases from the SEER database, 1973-2005

BACKGROUND

Previous reports of Ewing sarcoma cohorts suggested that there is a difference in incidence according to racial origin. However, to the authors' knowledge, this finding has never been tested in a population-based database, and the impact of race on clinical outcome and the significance of known risk factors stratified to racial groups have not been reported.

METHODS

Patients who had Ewing sarcoma diagnosed between 1973 and 2005 were identified in the Surveillance, Epidemiology, and End Results database. Patient demographic and clinical characteristics; incidence; year of diagnosis; tumor location, tumor size, and disease stage at diagnosis; treatment(s); cause of death; and survival were extracted. Kaplan-Meier, log-rank, and Cox regressions were used to analyze the significance of prognostic factors.

RESULTS

Race-specific incidence indicated that Caucasians have the highest incidence (0.155), followed by Asians/Pacific Islanders (0.082), and African Americans (0.017). The difference in incidence between Caucasians and African Americans was 9-fold and significant (P<.001). The incidence of Ewing sarcoma increased over the past 3 decades among Caucasians (P<.05). Survival was not impacted by race. Local disease stage, primary tumor location in the appendicular skeleton, and tumor size

CONCLUSIONS

To the authors' knowledge, this is the first report focusing on racial disparity in incidence of Ewing sarcoma. Caucasians were affected more frequently, although outcomes were similar between races. It is noteworthy that being a woman constituted a survival benefit only among the Caucasian patients. Further studies will need to clarify the reasons for racial disparities in incidence and for sex differences in survival.

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Key Words Collapse

MESH Headings

• Adolescent
• Adult
• Black People
• Bone Neoplasms/epidemiology
• Bone Neoplasms/ethnology
• Bone Neoplasms/mortality
• Child
• Child, Preschool
• Female
• Hispanic or Latino
• Humans
• Incidence
• Infant
• Infant, Newborn
• Middle Aged
• Prognosis
• Racial Groups
• Risk Factors
• SEER Program
• Sarcoma, Ewing/epidemiology
• Sarcoma, Ewing/ethnology
• Sarcoma, Ewing/mortality
• Sex Distribution
• White People
• Black or African American

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Grants Collapse

Affiliation(s)

Muhammad U Jawad Department of Orthopedics, University of Miami Miller School of Medicine, Miami, Florida 33136, USA
Michael C Cheung
Elijah S Min
Michaela M Schneiderbauer
Leonidas G Koniaris
Sean P Scully

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High-dose therapy with hematopoietic stem cell rescue in patients with poor prognosis Ewing family tumors

The purpose of the study was to evaluate the feasibility and safety of two cycles of high-dose chemotherapy (HDT) followed by autologous hematopoietic SCT (HSCT) in patients with poor prognosis Ewing family of tumors (EFT). Twenty patients with primary metastatic bulky disease or recurrent EFT were enrolled to a treatment protocol with two cycles of HDT and HSCT. Patients tolerated well the first (n=20) and second (n=13) cycles, with limited and predictable toxicities. Only one (5%) TRM occurred during the second cycle. Myeloid engraftment occurred at the median of 11 days after both cycles. At 3 years, the overall and EFS were 45% (confidence interval; CI 0.22, 0.69) and 47% (CI 0.25, 0.70), respectively, for the entire group and 58% (CI 0.30, 0.86) for patients who completed two cycles. Dose intensification with two cycles of HDT and HSCT is feasible and safe, with low and acceptable treatment-related morbidity and mortality. Adding a second course of therapy does not impair engraftment. However, only 65% of the patients were able to proceed to the second cycle. Further studies are required to define the optimal mode of delivery of HDT and HSCT in treatment of advanced EFT.

Sarcoma

Sarcomas comprise a heterogeneous group of mesenchymal neoplasms. They can be grouped into 2 general categories, soft tissue sarcoma and primary bone sarcoma, which have different staging and treatment approaches. This review includes a discussion of both soft tissue sarcomas (malignant fibrous histiocytoma, liposarcoma, leiomyosarcoma, synovial sarcoma, dermatofibrosarcoma protuberans, angiosarcoma, Kaposi sarcoma, gastrointestinal stromal tumor, aggressive fibromatosis or desmoid tumor, rhabdomyosarcoma, and primary alveolar soft-part sarcoma) and primary bone sarcomas (osteosarcoma, Ewing sarcoma, giant cell tumor, and chondrosarcoma). The 3 most important prognostic variables are grade, size, and location of the primary tumor. The approach to a patient with a sarcoma begins with a biopsy that obtains adequate tissue for diagnosis without interfering with subsequent optimal definitive surgery. Subsequent treatment depends on the specific type of sarcoma. Because sarcomas are relatively uncommon yet comprise a wide variety of different entities, evaluation by oncology teams who have expertise in the field is recommended. Treatment and follow-up guidelines have been published by the National Comprehensive Cancer Network (www.nccn.org).

Exploitable mechanisms for combining drugs with radiation: concepts, achievements and future directions

Widening indications for combining radiation therapy with cytotoxic or molecular-targeted drugs have mainly been driven by pragmatic clinical trials. With a flurry of novel drugs in various stages of preclinical and clinical development there is a need to revise the framework that has traditionally been used for discussing possible drug-radiation interactions, especially because many of the new drugs are directed at a specific molecular target. Spatial cooperation, cytotoxic enhancement, biological cooperation, temporal modulation and normal tissue protection are proposed as five primary exploitable mechanisms for the rational combination of drugs with radiation for cancer therapy. These five mechanisms produce different clinical outcomes and, therefore, the optimum clinical end point for assessing therapeutic benefit will depend on the mechanism tested. The dependence of outcome on these mechanisms also affects the selection of preclinical models and the optimum scheduling of the two modalities, i.e. the timing and dosing of the drug relative to the radiation dose fractions. These considerations are discussed in some detail for each mechanism and illustrated with specific clinical examples. Multi-modality therapy for head and neck squamous-cell carcinoma is used to illustrate these concepts. Further clinical progress in this field will require hypothesis-driven trials to ensure efficient identification of treatments with the most favorable risk:benefit ratio.

Safety assessment of intensive induction with vincristine, ifosfamide, doxorubicin, and etoposide (VIDE) in the treatment of Ewing tumors in the EURO-E.W.I.N.G. 99 clinical trial

BACKGROUND

The EUROpean Ewing tumour Working Initiative of National Groups 1999 (EURO-E.W.I.N.G. 99) protocol prescribes six courses of vincristine, ifosfamide, doxorubicin, and etoposide (VIDE) as intensive induction chemotherapy for Ewing tumors (ET). Granulocyte-colony stimulating factor (G-CSF) is recommended. Adverse reactions (AR) were evaluated; quality assurance of data collection reviewed.

PROCEDURE

Safety data from 4,746 courses of VIDE in 851 patients less than 50 years with ET were collected using a checklist and evaluated using descriptive statistics with sub-groups including gender, age, and tumor volume, analyzed by Wilcoxon and Kruskal-Wallis tests.

RESULTS

Myelosuppression and infections were the major AR but with appropriate supportive therapy targeted dose intensity was maintained. Five VIDE-related deaths with three due to sepsis were reported. Renal and cardiac toxicity were reflected by glomerular filtration rate (GFR) <39 ml/min/1.73 m2 in 0.1%, tubular phosphate reabsorption < or = 0.80 in 1.9%, and left ventricular shortening fracture <28% in 2.5% VIDE courses. Statistically significant gender-associated AR concerning hemoglobin and platelets were observed with females > males as were age-associated AR concerning hemoglobin, WBC, platelets, stomatitis, and vomiting with AR decreasing with age, that is, children > adolescents > adults. No association of AR to tumor volume was found. In VIDE courses with and without G-CSF, neutropenia-related fever in 60.8% and 65.8%, and infection in 54.7% and 61.0% courses, respectively, were recorded.

CONCLUSIONS

AR under VIDE remained within the expected range. Some AR, for example, hematotoxicity were significantly influenced by age and gender but not by tumor volume. G-CSF did not significantly influence neutropenia-related fever and infection. Solicited safety collection with checklists adequately reflects the burden per course.

Ewing's sarcoma and primitive neuroectodermal family of tumors

Ewing's sarcoma (ES) initially was believed to be of perivascular endothelial origin. The Ewing's sarcoma family of tumors (EFT) includes ES of bone (ESB), extraosseous ES (EES), peripheral primitive neuroectodermal tumor of bone (pPNET), and malignant small-cell tumor of the thoracopulmonary region, or Askin's tumor, all of which are now known to be neoplasms of neuroectodermal origin. The degree of neuronal differentiation has been used for histopathologic subclassification of the EFT as classical ES (ESB or EES), which is characterized by minimal evidence of neural differentiation, and pPNET, which displays evidence of neural differentiation by standard microscopy, electron microscopy, or immunohistochemistry. Because the behavior, prognosis, and treatment appear to be similar for all subsets of EFT, this histopathologic subclassification may not be clinically significant, though some debate remains whether neural differentiation predicts for inferior outcome.

Spinal cord Ewing's sarcoma metastasis: presentation of one case

Cervical spinal Ewing's sarcomas are rare and cause problems in diagnosis. We present an unusual case of a primary extraosseous Ewing's sarcoma arising from the spinal cord. An 18-year-old woman with fever, headache and back pain lasting one month was admitted to the hospital. Whole body bone scintigraphy was performed with 1110 MBq technetium-99m methylenediphosphonate. Scintigraphy clearly showed abnormal technetium-99m methylenediphosphonate accumulation in the level of the 5th and 6th cervical vertebrae. Magnetic resonance imaging could also confirm this examination finding. After the scintigraphic study, the patient underwent surgery. Pathological diagnosis of the operation specimen was Ewing's sarcoma.