The use of chemotherapy in soft-tissue sarcomas

Biomarkers for immune checkpoint inhibition in sarcomas - are we close to clinical implementation?

Sarcomas are a group of diverse and complex cancers of mesenchymal origin that remains poorly understood. Recent developments in cancer immunotherapy have demonstrated a potential for better outcomes with immune checkpoint inhibition in some sarcomas compared to conventional chemotherapy. Immune checkpoint inhibitors (ICIs) are key agents in cancer immunotherapy, demonstrating improved outcomes in many tumor types. However, most patients with sarcoma do not benefit from treatment, highlighting the need for identification and development of predictive biomarkers for response to ICIs. In this review, we first discuss United States (US) Food and Drug Administration (FDA)-approved and European Medicines Agency (EMA)-approved biomarkers, as well as the limitations of their use in sarcomas. We then review eight potential predictive biomarkers and rationalize their utility in sarcomas. These include gene expression signatures (GES), circulating neutrophil-to-lymphocyte ratio (NLR), indoleamine 2,3-dioxygenase (IDO), lymphocyte activation gene 3 (LAG-3), T cell immunoglobin and mucin domain-containing protein 3 (TIM-3), TP53 mutation status, B cells, and tertiary lymphoid structures (TLS). Finally, we discuss the potential for TLS as both a predictive and prognostic biomarker for ICI response in sarcomas to be implemented in the clinic.

Epirubicin, cisplatin plus ifosfamide versus standard chemotherapeutic regimens for advanced/unresectable primary thoracic sarcomas

PURPOSE

Thoracic sarcomas are rare malignancies, with limited data for unresectable/advanced scenarios. Our goal is to provide insights of a three-drug chemotherapy regimen improving patient survival compared to standard regimens.

METHODS

Retrospective cohort analysis of patients diagnosed with unresectable/advanced primary thoracic sarcoma divided between primary pulmonary sarcomas (PPS) and chest wall sarcomas (CWS) comparing chemotherapeutical regimens efficacy. Not true soft tissue sarcomas (STS) for PPS were excluded from the analysis. Univariate and multivariate analysis performed via Cox-regression model. Progression-free survival (PFS) and overall survival (OS) analysis via Kaplan-Meier with hazard ratio (HR) obtained via Mantel-Haenszel or log rank.

RESULTS

157 total cases were included, from which 50 cases were PPS and 107 cases CWS. For PPS, 4 cases were excluded from the analysis as they were not true STS. The most common histology was undifferentiated sarcomas, 63% of cases were treated with E/C/I and 37% with another regimen. The E/C/I regimen demonstrated a benefit for both OS (p = 0.020) and PFS (p = 0.010) when compared to any other regimen as well as when compared to non-platinum regimens (p = 0.016 and p = 0.001). Regarding CWS, the most common histology was synovial and undifferentiated sarcomas, 55.1% were treated with E/C/I and 44.9% treated with another regimen. The E/C/I regimen did not demonstrate a benefit for OS or PFS compared to any other regimen, neither when compared to other non-platinum regimens. However, a benefit was observed in favor of E/C/I when compared to other platinum regimens in both OS (p = 0.049) and PFS (0.015). Both analyses for PPS and CWS demonstrated a benefit in favor of cisplatin therapies compared to carboplatin in both OS and PFS.

CONCLUSION

This study demonstrates that platinum therapy alone does not work, and that cisplatin must be the agent of choice and it's used in combination could increase treatment response. The E/C/I regimen demonstrated a in PPS but not for CWS, this is due do their rarity of PPS and that no standard treatment is established yet. The regimen proposed here could represent a possible new standard of treatment for PPS as long as it is validated in a prospective study.

Real-life incidence of cardiotoxicity and associated risk factors in sarcoma patients receiving doxorubicin

BACKGROUND

Anthracycline induced cardiotoxicity is well recognized but only few data exist in sarcoma patients. This study retrospectively aimed to analyze sequential Cadmium Zinc Telluride (CZT)-multigated equilibrium radionuclide angiography (ERNA) for monitoring left ventricular ejection fraction (LVEF) and to assess the real-life incidence of cardiotoxicity in sarcoma patients receiving doxorubicin based chemotherapy.

MATERIALS AND METHODS

A retrospective analysis was performed on all sarcoma patients referred to Herlev University Hospital between 2012 and 2015. Cardiotoxicity was defined as a decline in LVEF of > 10% percentage point to a LVEF < 50% as compared to baseline. Early cardiotoxicity was defined as < 1 year and late cardiotoxicity as ≥ 1 year. Recovery of cardiotoxicity was defined as a LVEF ≥ 50%.

RESULTS

A total of 149 patients were referred, 75 (50%) sarcoma patients were included. The main reason for exclusion was that only one CZT-ERNA had been performed in 50 (68%) of the patients. Twenty-three (31%) of the patients experienced cardiotoxicity, 11 (48%) were female, mean age was 56.9 years. Early cardiotoxicity was observed in 16 (70%) of the patients and 11 (48%) experienced clinical symptoms of cardiotoxicity at diagnosis. Recovery of LVEF was seen in 12 (55%) of the patients and persistent recovery in 10 (45%). The diastolic blood pressure at baseline was positively and significantly associated with a higher risk of developing cardiotoxicity (Relative Risk (RR): 1.039 (95% CI= 1.001 - 1.079; p = 0.042)). The median survival was 1.4 years (range 0.5 - 2.2 years) for patients with metastatic disease versus 3.9 years (range 1.5 - 6.4 years) (p = 0.009) for localized disease at baseline.

CONCLUSION

Cardiotoxicity is a relative frequent complication in sarcoma patients treated with doxorubicin based chemotherapy and the diastolic blood pressure at baseline was significantly associated with a higher risk of developing cardiotoxicity.

Bio fabrication of gold nanoparticles and their combination with chemotherapy and ultrasound for effective treatment of tumors

BACKGROUND AND OBJECTIVE

Chemotherapy is one of the important medical option for the cancer therapy, but still new combination of therapeutic treatment methods are needed to achieve efficient anti tumor activity. In this work, Pueraria lobata leaf extract was utilized as a bio reductant for the fabrication of the Gold nanoparticles (Au-NPs) by an ecological approach without using any harmful chemical. This work also evaluates whether the combined effect of chemotherapy along with Au-NPs and Ultrasound (US) is effective over the tumors or not.

MATERIALS AND METHODS

About 10 mL of plant extract was added to 1mM of HAuCl4 solution (20.0 mL) and pH was maintained at 12 and allowed for stirring for half an hour. The change in solution color from yellow to purple signified the Au-NPs formation.

RESULTS

XRD results and TEM images confirmed the formation of crystalline Au-NPs with sizes ranging from 23-30 nm. Further, biological studies revealed that the combination of Au-NPs and US along with chemotherapy improved the impact of anti-cancer drug.

CONCLUSION

In conclusion, Pueraria lobata leaf extract mediated synthesis of Au-NPs by an eco-friendly approach was reported in this work. The plant biomolecules of the extract were involved in the reduction and capping of the Au-NPs formed. The major conclusion is that addition of Au-NPs with chemotherapy and ultrasound has shown more effective anti-tumor activity.

Real-World Experiences with Pazopanib in Patients with Advanced Soft Tissue and Bone Sarcoma in Northern California

Background: Pazopanib was approved for advanced soft tissue sarcoma as a second- or third-line therapy based on the clinical trial "Pazopanib for metastatic soft-tissue sarcoma" (PALETTE). We hypothesized that the real-world experiences may be significantly different from the clinical trial results. Methods: We analyzed the response pattern of patients with advanced soft tissue and bone sarcoma who received pazopanib treatment between 1 January 2011 and 31 October 2018 in Kaiser Permanente Northern California. Results: A total of 123 patients with 23 different histologic subtypes were assessable. One patient with low-grade fibromyxoid sarcoma obtained complete response (CR) after 2 months of treatment with pazopanib, 12 patients (9.7%) obtained partial response (PR), 34 patients (27.6%) had stable disease (SD), while 76 patients (61.8%) developed progressive disease (PD). The disease control rate (DCR) was 46.3% (CR + PR + SD). Among the 12 patients with PR, 3 had undifferentiated pleomorphic sarcoma (UPS), 4 had leiomyosarcoma (LMS), 2 had pleomorphic rhabdomyosarcoma, 1 had pleomorphic liposarcoma, 1 had dedifferentiated liposarcoma, and 1 had angiosarcoma. The median duration of response was 9 months. Two patients with Ewing's sarcoma had SD for 6 and 13 months, and two patients with osteosarcoma had SD for 6 and 9 months. Among 65 patients assessed at 8 weeks, 9 had a response, and 10 had SD. Among 104 patients assessed at 12 weeks, 12 had a response, and 26 had SD. The median progression-free survival (PFS) was approximately 3 months for all 123 cases and for patients with UPS and LMS. Conclusions: Our cohort of patients with advanced soft tissue and bone sarcoma in Northern California treated with pazopanib had diverse histologic subtypes. The response rate (CR + PR) was higher than that of the PALETTE trial, while the DCR and the median PFS were significantly lower. The observation of PR in two patients with liposarcoma and durable SD in several patients with bone sarcoma indicates that pazopanib has activity in liposarcoma and bone sarcoma.

The combination of gemcitabine and nab-paclitaxel as a novel effective treatment strategy for undifferentiated soft-tissue sarcoma in a patient-derived orthotopic xenograft (PDOX) nude-mouse model

Undifferentiated/unclassified soft-tissue sarcomas (USTS) is recalcitrant neoplasms that is usually treated with doxorubicin (DOX)-containing regimens as first-line therapy. Nanoparticle albumin-bound paclitaxel (nab-PTX) is a nanotechnology-based drug and is widely used in pancreatic cancer in combination with gemcitabine (GEM). The major goal of the present study was to determine the efficacy of nab-PTX in combination with GEM, compared to conventional drugs such as docetaxel (DOC), GEM combined with DOC, or first-line drug DOX on a USTS not-otherwise specified (USTS/NOS) from a striated muscle implanted in the right biceps femoris muscle of nude mice to establish a patient-derived orthotopic xenograft (PDOX) model. USTS PDOX models were randomized into six groups: untreated control; DOX; DOC; nab-PTX; GEM combined with DOC; and GEM combined with nab-PTX. Tumor size and body weight were measured. Tumor growth was inhibited to the greatest extent by GEM combined with nab-PTX. Tumors treated with GEM combined with nab-PTX had the most necrosis. Body weight of the treated mice was not significantly different from the untreated controls. The present study demonstrates the power of the PDOX model to identify a novel effective treatment strategy of the combination of GEM and nab-PTX for recalcitrant soft-tissue sarcomas. These results suggest that combination of GEM and nab-PTX could be a promising therapeutic strategy for USTS.

MDR1 not CYP3A4 gene expression is the predominant mechanism of innate drug resistance in pediatric soft tissue sarcoma patients

BACKGROUND

Intratumoral up-regulation of genes coding for drug transporters and metabolizing enzymes, such as MDR1 and CYP3A4, after chemotherapy are linked to cancer drug resistance. However their expression in primary soft tissue sarcomas (STS) prior to drug treatment and their role in innate resistance remain unclear.

OBJECTIVE

The aim of this study was characterize MDR1 and CYP3A4 expression pattern before to chemotherapy and its clinical implication in pediatric STS.

METHODS

In this prospective study we analyzed MDR1 and CYP3A4 mRNA expression in both normal and tumor tissues from 28 newly diagnosed STS pediatric and then compared with patients' clinical-pathological data, including chemotherapy response.

RESULTS

Our data showed that the expression of the MDR1 gene was significantly higher in malignant tissue than in the normal tissues of patients with STS. In addition, high MDR1 expression was significantly associated with local advances, as well as poor response to treatment. In contrast, CYP3A4 expression level was negligible in both tumoral and non-tumoral tissues.

CONCLUSIONS

These results suggest that a significant mRNA level of MDR1 gene was intrinsically present in STS before exposure to chemotherapeutic drugs, suggesting that MDR1 may be important contributors of innate chemoresistance of this tumor type.

Health Care Resource Utilization and Costs among Adult Patients with Advanced Soft Tissue Sarcoma: A Retrospective Medical Record Review in the United Kingdom, Spain, Germany, and France

Objective

To describe health care resource utilization and costs for patients with advanced soft tissue sarcoma (STS) in the United Kingdom (UK), Spain, Germany, and France.

Methods

Physicians abstracted data for adult patients with a diagnosis of advanced STS (other than Kaposi's sarcoma or gastrointestinal stromal tumor) who received ≥1 lines of systemic therapy. Health care resource utilization related to advanced STS treatment was recorded; associated costs were estimated by applying unit costs.

Results

A total of 130 physicians provided data for 807 patients (UK: 199; Spain: 203; Germany: 204; and France: 201). The site of care during active treatment varied based on differences in the health care systems of these four countries. Total mean per-patient health care cost in the UK was £19,457; in Spain, €26,814; in Germany, €20,468; and in France, €24,368. Advanced STS-related systemic treatment costs were driven primarily by drug acquisition and administration costs. Treatment-related costs increased during later lines of therapy for all countries except France, where they decreased after first-line therapy. Pain control and antiemetics were the most common supportive care medications.

Conclusions

This study provides real-world data on resource utilization and estimated costs in advanced STS and could inform policymakers about treatment burden.

Patterns of sensitivity to a panel of drugs are highly individualised for undifferentiated/unclassified soft tissue sarcoma (USTS) in patient-derived orthotopic xenograft (PDOX) nude-mouse models

Undifferentiated/unclassified soft tissue sarcoma (USTS) is a recalcitrant disease; therefore, precise individualised therapy is needed. Toward this goal, we previously established patient-derived orthotopic xenograft (PDOX) models of USTS in nude mice. Here, we determined the extent of uniqueness of drug response in a panel on USTS PDOX models from 5 different patients. We previously showed that 3 of the 5 patients were resistant to doxorubicin (DOX) despite DOX being first-line therapy. Two weeks after orthotopic tumour implantation, PDOX mouse models were randomised into five groups: untreated control, DOX, gem-citabine/docetaxel (GEM/DOC), pazopanib (PAZ), temozolomide (TEM). Three PDOX cases were completely resistant to DOX. TEM had high efficacy for 4 USTS PDOX models, including DOX-resistant cases. GEM/DOC and PAZ were effective in three USTS PDOX. One case was completely resistant to TEM. Two cases were completely resistant to PAZ. The results showed the drug sensitivity pattern for each USTS PDOX was highly individualised and that at least one effective drug could be found for each. The PDOX model could be effective in precise individualised drug sensitivity testing which is especially important for heterogeneous cancers such as USTS, and can give the patient a greater chance to be treated with an effective drug.

Current treatment strategies in pediatric gastrointestinal stromal cell tumor

Gastrointestinal stromal tumors (GIST) are exceedingly rare tumors in the pediatric population. As a result, many clinicians either may never see this diagnosis or will encounter it only a few times throughout their careers. Additionally, the more we discover about this disease, it becomes evident that it represents a distinct clinical entity from adult GIST. Many of the treatments and strategies used to combat the adult tumor are either ineffective or may be harmful to the pediatric population with this disease. The unique tumor biology found in pediatric GIST necessitates unique approaches and treatment strategies in order to achieve the best clinical outcome. This review aims to discuss the most recent data available on the different therapeutic modalities utilized in cases of Pediatric GIST.

Treatment Patterns and Survival among Adult Patients with Advanced Soft Tissue Sarcoma: A Retrospective Medical Record Review in the United Kingdom, Spain, Germany, and France

Objective

To describe real-world treatment patterns and outcomes for patients with advanced soft tissue sarcoma (STS) not amenable to surgery or radiotherapy in the United Kingdom, Spain, Germany, and France.

Methods

Physicians completed a web-based medical record abstraction for adult patients with advanced STS (other than Kaposi's sarcoma or gastrointestinal stromal tumor) who received ≥1 line of systemic therapy. Clinical characteristics, treatments, tumor responses, and mortality data were recorded.

Results

A total of 130 physicians provided data for 807 patients. Patients' mean age at advanced STS diagnosis was 57.1 (±12.3) years; 59% were male. The most commonly identified histologic categories were leiomyosarcoma (28%), liposarcoma (13%), and rhabdomyosarcoma (11%). Overall, 57% of patients received only 1 line of therapy, 32% received 2 lines of therapy, and 11% received ≥3 lines of therapy. The most common first-line regimens were doxorubicin alone (41%), doxorubicin plus ifosfamide (19%), docetaxel plus gemcitabine (9%), paclitaxel alone (4%), and ifosfamide (4%). Median overall survival from start of treatment was estimated to be 17.6 months (95% confidence interval, 15.6–19.0 months).

Conclusions

In real-world clinical practice, advanced STS is most commonly treated with older therapies in the United Kingdom, Spain, Germany, and France. New therapies that improve overall survival in advanced STS are needed.

Treatment patterns and survival among older adults in the United States with advanced soft-tissue sarcomas

Background

To describe patient and tumor characteristics, treatments, and survival among older adults in the United States with advanced soft-tissue sarcoma (STS), across and by categories of specifically defined histologic subtypes.

Methods

We conducted a retrospective cohort analysis using the SEER. The study population comprised patients ≥ 65 years old with advanced STS (excluding osteosarcoma, Kaposi sarcoma, and gastrointestinal stromal tumors) diagnosed from January 1, 2001 to December 31, 2011.

Results

Of 4274 study patients, 2103 (49.2%) were male. Mean age was 77.8 years, and 1539 (36.0%) had distant disease at initial diagnosis. The most common histologic categories were leiomyosarcoma (922[21.6%]), undifferentiated pleomorphic sarcoma (652[15.3%]), and liposarcoma (554[13.0%]). Overall, 1227 (28.7%) patients received first-line systemic therapy. Among these patients, 325 (26.5%) received docetaxel plus gemcitabine and 231 (18.8%) received doxorubicin alone. Only 476 patients received second-line therapy (11.1%), most commonly doxorubicin alone (n = 101). Median overall survival (95% confidence interval) from advanced STS diagnosis was 8.9 (8.3, 9.7) months.

Conclusions

Although previous studies of younger populations reported anthracycline-based therapy predominated in first line, our study of older advanced STS patients found that docetaxel plus gemcitabine was most commonly used. Despite variation by histologic category, prognosis remains poor for older adult patients with advanced STS.

Electronic supplementary material

The online version of this article (10.1186/s13569-018-0094-x) contains supplementary material, which is available to authorized users.

Individualized doxorubicin sensitivity testing of undifferentiated soft tissue sarcoma (USTS) in a patient-derived orthotopic xenograft (PDOX) model demonstrates large differences between patients

Doxorubicin (DOX) is often first-line treatment of undifferentiated/unclassified soft tissue sarcoma (USTS). However, the DOX response rate for USTS patients is low. Individualized precision-medicine technology that could identify DOX responders as well as non-responders would be of high value to cancer patients. In the present study, we established 5 patient-derived orthotopic xenograft (PDOX) nude mouse models from 5 USTS patients and evaluated the efficacy of DOX in each PDOX model. USTS's were grown orthotopically in the right thigh of nude mice to establish the PDOX models. Two weeks after implantation, the mouse models were randomized into two groups of 8 mice each: untreated control; and DOX (3 mg/kg, i.p., once a week for 2 weeks). DOX showed significant growth inhibition in only 2 USTS PDOX models out of 5 (p = 0.0054, p = 0.0055, respectively) on day 14 after initiation. DOX was ineffective in the other 3 PDOX models. However, even in the DOX-sensitive cases, DOX could not regress the PDOX tumors responding to treatment. The present study has important implications since this is the first in vivo study to compare the DOX sensitivity for USTS on multiple patient tumors. We showed that only two of five USTS were responsive to DOX, despite DOX being first line chemotherapy for USTS. The 3 resistant cases should not be treated with DOX clinically, in order to spare the patients' unnecessary toxicity. This PDOX model is useful for precise individualized drug sensitivity testing, especially for rare heterogeneous recalcitrant sarcomas such as USTS.

Tumor-targeting Salmonella typhimurium A1-R is a highly effective general therapeutic for undifferentiated soft tissue sarcoma patient-derived orthotopic xenograft nude-mouse models

Undifferentiated soft tissue sarcoma (USTS) is a recalcitrant and heterogeneous subgroup of soft tissue sarcoma with high risk of metastasis and recurrence. Due to heterogeneity of USTS, there is no reliably effective first-line therapy. We have generated tumor-targeting Salmonella typhimurium A1-R (S. typhimurium A1-R), which previously showed strong efficacy on single patient-derived orthotopic xenograft (PDOX) models of Ewing's sarcoma and follicular dendritic cell sarcoma. In the present study, tumor resected from 4 patients with a biopsy-proven USTS (2 undifferentiated pleomorphic sarcoma [UPS], 1 undifferentiated sarcoma not otherwise specified [NOS] and 1 undifferentiated spindle cell sarcoma [USS]) were grown orthotopically in the biceps femoris muscle of mice to establish PDOX models. One USS model and one UPS model were doxorubicin (DOX) resistant. One UPS and the NOS model were partially sensitive to DOX. DOX is first-line therapy for these diseases. S. typhimurium A1-R arrested tumor growth all 4 models. In addition to arresting tumor growth in each case, S. typhimurium A1-R was significantly more efficacious than DOX in each case, thereby surpassing first-line therapy. These results suggest that S. typhimurium A1-R can be a general therapeutic for USTS and possibly sarcoma in general.

Antagonism in effectiveness of evofosfamide and doxorubicin through intermolecular electron transfer

Hypoxic cells pose a problem in anticancer chemotherapy, in which often drugs require oxygen as an electron acceptor to bring about the death of actively cycling cells. Bioreductive anticancer drugs, which are selectively activated in the hypoxic regions of tumours through enzymatic one-electron reduction, are being developed for combination with chemotherapy-, radiotherapy- and immunotherapy-containing regimens to kill treatment-resistant hypoxic cells. The most clinically-advanced bioreductive drug, evofosfamide (TH-302), which acts by releasing a DNA-crosslinking mustard, failed to extend overall survival in combination with doxorubicin, a topoisomerase II inhibitor, for advanced soft tissue sarcoma in a pivotal clinical trial. However, the reasons for the lack of additive efficacy with this combination are unknown. Here, we show that the radical anion of evofosfamide undergoes electron transfer to doxorubicin in kinetic competition to fragmentation of the radical anion, thus suppressing the release the cytotoxic mustard. This electron transfer process may account, at least in part, for the lack of overall survival improvement in the recent clinical trial. This study underlines the need to consider both redox and electron transfer chemistry when combining bioreductive prodrugs with other redox-active drugs in cancer treatment.

Photochemical internalization (PCI) of bleomycin is equally effective in two dissimilar leiomyosarcoma xenografts in athymic mice

BACKGROUND

Photochemical internalization (PCI) is a novel technique for delivery of active macromolecules into cancerous cells, via light activation of a specific photosensitizer and a low dose systemic drug. Numerous pre-clinical studies and one clinical trial have confirmed the treatment potential in carcinomas. Soft tissue sarcomas are rare and generally resistant to radio- and chemotherapy. Due to treatment resistance and surgical morbidity in sarcoma care, we seek to increase knowledge on PCI effects in sarcomas by studying two different, but closely related leiomyosarcomas.

METHODS

MES-SA and SK-LMS-1 tumours were established in the leg muscles of athymic mice. Treatment effects after AlPcS_2a-PCI of bleomycin, PCI with no drug (photodynamic therapy, PDT) and control groups were evaluated by: 1) assessment of tumour growth, 2) uptake of contrast agent during MRI and 3) histopathology.

RESULTS

PCI of bleomycin induced a similar and significant increase in time to reach the end point in both tumour models, while neither responded to AlPcS_2a-PDT. In the MES-SA tumours PCI reduced the growth rate, while in the SK-LMS-1 tumours the growth was blocked for 12days followed by exponential growth close to that of untreated tumours. SK-LMS-1 tumours were more homogenously and better vascularized than MES-SA. After PCI the vascular shutdown was more complete in the SK-LMS-1 tumours than in the MES-SA tumours.

CONCLUSIONS

AlPcS2a-based PCI, but not PDT, induced significant tumour growth delay in the evaluated sarcomas. Cellular responsiveness to bleomycin and tumour vascularity are identified as predictive markers for PCI treatment effects.

Retroperitoneal Sarcomas

BACKGROUND

The evaluation and treatment of retroperitoneal sarcomas are challenging because the tumors are relatively rare and frequently present with advanced disease in an anatomically complex location.

METHODS

We reviewed the literature on experience in the management of retroperitoneal sarcomas, and we present our own experience in the treatment of these tumors.

RESULTS

The identification of prognostic factors other than the adequacy of resection has been inconsistent. Due to a lack of associated symptoms, retroperitoneal sarcomas smaller than 5 cm are rare. Computed tomography is the most useful tool in the evaluation of retroperitoneal tumors. Surgery, radiation therapy, and chemotherapy are treatment options, but the most important factor in the treatment of primary tumors is complete surgical resection. The role of neoadjuvant and adjuvant therapies is not defined and should be considered within the context of clinical trials.

CONCLUSIONS

Early referral of patients with retroperitoneal soft tissue tumors will help to ensure that they will receive the benefits of multidisciplinary evaluation and treatment of their disease and ready access to clinical trials.

Olaratumab: PDGFR-α inhibition as a novel tool in the treatment of advanced soft tissue sarcomas

Advanced soft tissue sarcomas are aggressive cancers with limited therapeutic options. Recently, inhibition of platelet-derived growth factor receptor (PDGFR)-α by the monoclonal antibody olaratumab showed promising clinical activity. If confirmed, this would be one of the first examples of targeted therapy effective in advanced soft tissue sarcomas therapy independently of the histologic subtype. Here, we reviewed the biology of the PDGF/PDGFR axis, particularly focusing on its role in cancer, and then we discussed on the effects of PDGFR-α inhibition in the therapy of advanced soft tissue sarcomas.

Tumors Sharply Increased after Ceasing Pazopanib Therapy for a Patient with Advanced Uterine Leiomyosarcoma: Experience of Tumor Flare

Pazopanib has activity in patients with soft-tissue sarcoma. We report an advanced uterine leiomyosarcoma case that suddenly worsened after cessation of pazopanib therapy. A 47-year-old woman had a primary uterine leiomyosarcoma tumor and multiple lung metastases, which progressed during her initial treatment. In subsequent treatment with pazopanib for 3 months, the sum of her tumor diameters after cessation sharply increased for two weeks. Symptoms such as dyspnea suddenly worsened also. She died of the disease one month after cessation of pazopanib therapy. Given the poor prognosis of recurrent uterine leiomyosarcoma and the rapid tumor enlargement after ending pazopanib therapy, control of this disease is especially important. Therefore, the decision to discontinue pazopanib therapy requires careful consideration.

VIP (etoposide, ifosfamide, and cisplatin) in patients with previously treated soft tissue sarcoma

We retrospectively reviewed outcomes of treatment with VIP (combination of etoposide, ifosfamide, and cisplatin) in patients with previously treated soft tissue sarcoma (STS).We analyzed the medical records of patients with advanced or relapsed STS who had undergone VIP treatment as second-line or more chemotherapy between January 2000 and December 2015. The patients were treated with a combination of etoposide (100 mg/m for 5 days), ifosfamide (2000 mg/m for 2 days), and cisplatin (20 mg/m for 5 days) once every 4 weeks. Treatment response, progression-free survival (PFS), and overall survival (OS) were analyzed in all patients and between responder and nonresponder groups (responders showed a tumor response to any prior systemic chemotherapy before VIP).Twenty-four patients with a median age of 50 years (range: 20-68 years) were treated with VIP. Eleven (45.8%) patients were male and 7 (29.2%) received 2 or more chemotherapy regimens before VIP. Median PFS was 3.7 months (95% confidence interval [CI], 1.3-6.1 months) and median OS was 10.0 months (95% CI, 6.6-13.5). The overall response rate was 37.5%, and the disease control rate was 50%. The responder group showed better PFS (7.7 months vs 3.0 months; P = 0.101) and significantly improved OS (11.0 months vs 8.8 months; P = 0.039) compared to those of nonresponders. All patients reported some grade of hematological toxicity. The most frequently encountered hematological toxicity was neutropenia (any grade, 77.7%; grade 3 or 4, 74.0%).VIP might be effective in patients with previously treated STS.

Nonconvulsive Status Epilepticus Due to Ifosfamide

Objective:

To report 2 cases of nonconvulsive status epilepticus (NCSE) following infusion of ifosfamide.

Case Summaries:

Two patients who received ifosfamide-containing chemotherapy developed NCSE. One woman received ifosfamide 1000 mg/m2 (1 h infusion on days 1–5); confusion, lethargy, and speech deterioration developed on day 3. The second patient developed similar symptoms on day 3 of treatment with 2500 mg/m2. Both patients responded to intravenous administration of diazepam 10 mg and were given levetiracetam as maintenance therapy.

Discussion:

The severity and presentation of central nervous system toxicity due to ifosfamide varies greatly and involves a spectrum ranging from subclinical electroencephalogram changes to coma. NCSE, an epileptic disorder in which typical convulsive activity is absent, has previously been reported in only 4 patients receiving ifosfamide. Levetiracetam may be used for maintenance antiepileptic therapy after diazepam administration.

Conclusions:

Among the many presentations of ifosfamide neurotoxicity, clinicians should consider NCSE as a possible explanation for changes in consciousness in a patient receiving this agent. An objective causality assessment by use of the Naranjo probability scale revealed that NCSE due to ifosfamide was probable.

A case report of pancreatic metastasis from synovial sarcoma successfully treated by metastasectomy with adjuvant chemotherapy

INTRODUCTION

Synovial sarcoma is a malignant soft tissue sarcoma which arises near joints. The most frequent metastasis sites of synovial sarcoma are the lungs, lymph nodes, and bone. Pancreatic metastasis is quite rare; only 3 cases have been reported worldwide to date. We herein present the 4th case of pancreatic metastasis from synovial sarcoma.

METHODS AND RESULTS

A 32-year-old man underwent extended excision of synovial sarcoma in the left pelvis and femur in 2009. In 2013, follow-up contrast-enhanced computed tomography revealed a 35-mm heterogeneously enhanced mass in the pancreas body. Endoscopic ultrasound-guided fine needle aspiration of the mass revealed a diffuse proliferation of atypical spindle cells in a fascicular arrangement. Because the histology was quite similar to the resected specimen of synovial sarcoma in 2009, the mass was suspected to be a metastasis from synovial sarcoma. Laparoscopic distal pancreatectomy with adjuvant adriamycin/ifosfamide chemotherapy was subsequently performed. Synovial sarcoma-specific SS18-SSX1 (synovial sarcoma translocation, chromosome 18-synovial sarcoma X1) or SS18-SSX2 chimera mRNA was detected in the resected specimen, confirming the diagnosis of metastasis from synovial sarcoma. The patient did well for 30 months without recurrence.

CONCLUSION

This case suggests that pancreatic metastasis from synovial sarcoma can be successfully treated by metastasectomy with adjuvant chemotherapy.

Primary Splenic Angiosarcoma Presenting as Idiopathic Thrombocytopenic Purpura: A Case Report and Review of the Literature

Angiosarcoma of the spleen is a rare malignancy that arises from vascular endothelial origin. This neoplasm is highly malignant and diagnosis is often delayed due to the vague presentation of clinical symptoms. A case report and concise review of the current diagnostic criteria and surgical treatment are provided to aid in the detection and treatment of this malignancy. We present a case of a 56-year-old female who presented with massive splenomegaly secondary to angiosarcoma of the spleen. The patient suffered from longstanding symptomatic anemia and thrombocytopenia. Diagnosis of a splenic angiosarcoma can be difficult due to the vague presentation and lack of concrete risk factors. Early identification and splenectomy are paramount. However, it is an aggressive malignancy with poor prognosis. We reviewed the literature of the current diagnostic and surgical treatment of primary splenic angiosarcoma.

Xenograft models for undifferentiated pleomorphic sarcoma not otherwise specified are essential for preclinical testing of therapeutic agents

Undifferentiated pleomorphic sarcoma not otherwise specified belongs to the heterogeneous group of soft tissue tumors. It is preferentially located in the upper and lower extremities of the body, and surgical resection remains the only curative treatment. Preclinical animal models are crucial to improve the development of novel chemotherapeutic agents for the treatment of undifferentiated pleomorphic sarcoma. However, this approach has been hampered by the lack of reproducible animal models. The present study established two xenograft animal models generated from stable non-clonal cell cultures, and investigated the difference in chemotherapeutic effects on tumor growth between undifferentiated pleomorphic sarcoma in vivo and in vitro. The cell cultures were generated from freshly isolated tumor tissues of two patients with undifferentiated pleomorphic sarcoma. For the in vivo analysis, these cells were injected subcutaneously into immunodeficient mice. The mice were monitored for tumor appearance and treated with the most common or innovative chemotherapeutic agents available to date. Furthermore, the same drugs were administered to in vitro cell cultures. The most effective tumor growth inhibition in vitro was observed with doxorubicin and the histone deacetylase inhibitor suberoylanilide hydroxamic acid (SAHA), also known as vorinostat. In the in vivo xenograft mouse model, the combination of doxorubicin and the tyrosine kinase inhibitor pazopanib induced a significant tumor reduction. By contrast, treatment with vorinostat did not reduce the tumor growth. Taken together, the results obtained from drug testing in vitro differed significantly from the in vivo results. Therefore, the novel and reproducible xenograft animal model established in the present study demonstrated that in vivo models are required to test potential chemotherapeutic agents for the treatment of undifferentiated pleomorphic sarcoma prior to clinical use, since animal models are more similar to humans, compared with in vitro cell cultures.

A Phase I/II Clinical Trial of Belinostat (PXD101) in Combination with Doxorubicin in Patients with Soft Tissue Sarcomas

Background. Belinostat is a novel histone deacetylase inhibitor. Primary Objectives. Maximum tolerated dose (MTD) and dose limiting toxicities (DLTs) of belinostat (Bel) in combination with doxorubicin (Dox) in solid tumours (phase I) and response rate (RR) in soft tissue sarcomas (phase II). Methods. Bel was administered as a 30-minute IV infusion on days 1–5 and on day 5 with Dox. The dose escalation schedule was as follows: cohort 1: Bel 600 mg/m² and 50 mg/m² Dox, cohort 2: Bel 600 mg/m² and 75 mg/m² Dox, cohort 3: Bel 800 mg/m² and 75 mg/m² Dox, and cohort 4: Bel 1000 mg/m² and 75 mg/m² Dox. Results. 41 patients were included (25 in phase I, 16 in phase II). Adverse events were fatigue (95%), nausea (76%), and alopecia (63%). There was one DLT, grade 3 rash/hand and foot syndrome. MTD was Bel 1000 mg/m²/d and Dox 75 mg/m². Four responses were seen: 2 PR in phase I, RR of 8%; in phase II, 1 PR/1 CR, RR of 13%, and 9 patients (56%) with SD. Conclusion. The combination was well tolerated. Response rate was moderate but median time to progression was 6.0 months (95% CI, 1.6–9.7 months) which is superior to some reports of single-agent Dox.

Notch Signaling Mediates Skeletal Muscle Atrophy in Cancer Cachexia Caused by Osteosarcoma

Skeletal muscle atrophy in cancer cachexia is mediated by the interaction between muscle stem cells and various tumor factors. Although Notch signaling has been known as a key regulator of both cancer development and muscle stem cell activity, the potential involvement of Notch signaling in cancer cachexia and concomitant muscle atrophy has yet to be elucidated. The murine K7M2 osteosarcoma cell line was used to generate an orthotopic model of sarcoma-associated cachexia, and the role of Notch signaling was evaluated. Skeletal muscle atrophy was observed in the sarcoma-bearing mice, and Notch signaling was highly active in both tumor tissues and the atrophic skeletal muscles. Systemic inhibition of Notch signaling reduced muscle atrophy. In vitro coculture of osteosarcoma cells with muscle-derived stem cells (MDSCs) isolated from normal mice resulted in decreased myogenic potential of MDSCs, while the application of Notch inhibitor was able to rescue this repressed myogenic potential. We further observed that Notch-activating factors reside in the exosomes of osteosarcoma cells, which activate Notch signaling in MDSCs and subsequently repress myogenesis. Our results revealed that signaling between tumor and muscle via the Notch pathway may play an important role in mediating the skeletal muscle atrophy seen in cancer cachexia.

Targeting EZH2-mediated methylation of H3K27 inhibits proliferation and migration of Synovial Sarcoma in vitro

Synovial sarcoma is an aggressive soft tissue sarcoma genetically defined by the fusion oncogene SS18-SSX. It is hypothesized that either SS18-SSX disrupts SWI/SNF complex inhibition of the polycomb complex 2 (PRC2) methyltransferase Enhancer of Zeste Homologue 2 (EZH2), or that SS18-SSX is able to directly recruit PRC2 to aberrantly silence target genes. This is of potential therapeutic value as several EZH2 small molecule inhibitors are entering early phase clinical trials. In this study, we first confirmed EZH2 expression in the 76% of human synovial sarcoma samples. We subsequently investigated EZH2 as a therapeutic target in synovial sarcoma in vitro. Knockdown of EZH2 by shRNA or siRNA resulted in inhibition of cell growth and migration across a series of synovial sarcoma cell lines. The EZH2 selective small-molecule inhibitor EPZ005687 similarly suppressed cell proliferation and migration. These data support the hypothesis that targeting EZH2 may be a promising therapeutic strategy in the treatment of synovial sarcoma; clinical trials are initiating enrollment currently.

Long-Term Clinical Responses of Neoadjuvant Dendritic Cell Infusions and Radiation in Soft Tissue Sarcoma

Purpose. Patients with large >5 cm, high-grade resectable soft tissue sarcomas (STS) have the highest risk of distant metastases. Previously we have shown that dendritic cell (DC) based vaccines show consistent immune responses. Methods. This was a Phase I single institution study of neoadjuvant radiation with DC injections on 18 newly diagnosed high-risk STS patients. Neoadjuvant treatment consisted of 50 Gy of external beam radiation (EBRT), given in 25 fractions delivered five days/week, combined with four intratumoral injections of DCs followed by complete resection. The primary endpoint was to establish the immunological response to neoadjuvant therapy and obtain data on its clinical safety and outcomes. Results. There were no unexpected toxicities or serious adverse events. Twelve out of 18 (67%) patients were alive, of which an encouraging 11/18 (61%) were alive with no systemic recurrence over a period of 2-8 years. Favorable immunological responses correlated with clinical responses in some cases. Conclusions. This study provides clinical support to using dendritic cell injections along with radiation in sarcomas, which when used optimally in combination can help clinical outcomes in soft tissue sarcoma. Study registration number is NCT00365872.

A Phase II Study of Gemcitabine, Vincristine, and Cisplatin As Second-Line Treatment for Patients with Advanced Soft Tissue Sarcoma

Patients with advanced soft tissue sarcoma (aSTS) typically have a poor prognosis. Patients progressing to doxorubicin-based regimen have limited therapeutic options. Monotherapy with cytotoxic drugs appears to have only modest activity in the second-line setting. The purpose of this phase II study was to prospectively evaluate the safety and efficacy of combination regimen with gemcitabine, vincristine, and cisplatin (GVP) as a salvage treatment for patients with aSTS.Eligible patients were female with 18∼75 years old, and had aSTS that had progressed after 1 prior anthracyclines-based chemotherapy regimen. Patients were treated with 1,000 mg/m gemcitabine intravenously (IV) on days 1 and 8, 1.4 mg/m (max 2 mg) vincristine IV on day 1 and 25 mg/m cisplatin IV on days 1 through 3 every 21 days until disease progression, unacceptable toxicity or up to 6 cycles. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), over response rate (ORR) and safety. This trial was registered with http://www.clinicaltrials.gov (no. NCT01192633).A total of 26 patients with a median age 47 years (21-72) were recruited. ORR was 23.1% [1 complete response and 5 partial responses]. The median PFS and OS were 4.8 (95% CI, 0.1-9.5) months and 15.0 (95% CI, 6.1-23.9) months, respectively. Grade 3/4 hematologic toxicities included neutropenia (34.6%), leukopenia (23.1%), thrombocytopenia (11.5%) and anemia (3.8%). No febrile neutropenia and grade 3/4 non-hematologic toxicities occurred. The most frequent non-hematologic toxicities were nausea/vomiting (50.0%), fatigue (30.8%), and fever (11.5%).We conclude that GVP regimen is effective with a favorable safety profile as the second-line chemotherapy in aSTS patients, which warrants further investigation in a phase III study.

Survival After Resection of Gastrointestinal Stromal Tumor and Sarcoma Liver Metastases in 146 Patients

BACKGROUND

We investigated outcomes by primary tumor type in patients who underwent resection of liver metastases from gastrointestinal stromal tumors (GIST), leiomyosarcomas, and other sarcomas.

METHOD

Our institutional liver database was used to identify patients who underwent resection from 1998 through 2013. Histopathological, clinical, and survival data were analyzed.

RESULTS

One hundred forty-six patients underwent resection of liver metastases from GIST (n = 49), leiomyosarcomas (n = 47), or other sarcomas (n = 50). The 5-year overall survival (OS) rates in patients with GIST, leiomyosarcomas, and other sarcomas were 55.3, 48.4, and 44.9%, respectively, and the 10-year OS rates were 52.5, 9.2, and 23.0%, respectively. The 5-year recurrence-free survival (RFS) rate was better for GIST (35.7%; p = 0.003) than for leiomyosarcomas (3.4%) and other sarcomas (21.4%). Lung recurrence was more common for leiomyosarcomas (36% of patients; p < 0.0001) than for other sarcomas (12%) and GIST (2%). For GIST, the findings support a benefit of imatinib regarding the 5-year RFS rate compared to resection alone (47.1 vs. 9.5%; p = 0.013). For leiomyosarcoma, primary tumor location did not affect the 5-year RFS rate (intraabdominal 14.5%; other location 0%; p = 0.182).

CONCLUSION

Liver metastases from GIST, leiomyosarcomas, and other sarcomas should be assessed separately as their survival and recurrence patterns are different. This is especially important for GIST, for which imatinib is now available.

Antitumor effect of YM155, a novel small-molecule survivin suppressant, via mitochondrial apoptosis in human MFH/UPS

Survivin is a member of the inhibitor of apoptosis family, which is known to inhibit mitochondrial apoptosis. Survivin is highly expressed in cancers and plays an important role in cancer cell survival, and increased survivin expression is an unfavorable prognostic marker in cancer patients. YM155, a novel small-molecule survivin suppressant, selectively suppresses survivin expression, resulting in the induction of apoptosis in various malignancies. However, the roles of survivin in human malignant fibrous histiocytoma/undifferentiated pleomorphic sarcoma (MFH/UPS) have not been studied. In the present study, we examined survivin expression in human musculoskeletal tumor tissues, and the effect of survivin inhibition by siRNA or YM155 on apoptotic activity in human MFH/UPS cell lines. In tumor tissues, mRNA expression of survivin was significantly higher in MFH/UPS samples than in benign schwannomas. Moreover, in vitro studies revealed that both survivin siRNA and YM155 suppressed survivin expression and inhibited MFH/UPS cell proliferation in a dose- and a time-dependent manner. Further, the numbers of apoptotic cells significantly increased with YM155 treatment. In vivo, tumor volume in YM155-treated groups was significantly reduced without significant bodyweight loss. Increased apoptotic activity along with decreased survivin expression was also observed in YM155-treated tumors. The findings in this study strongly suggest that survivin suppressants, including YM155, contribute to the suppression of human MFH/UPS cell growth via promoting mitochondrial apoptosis, and that survivin may be a potent therapeutic target for the novel treatment of human MFH/UPS.

Targeted therapy in sarcomas other than GIST tumors

Non-GIST soft tissue sarcomas are a heterogeneous grouping of mesenchymal tumors that comprise less than 1% of adult malignancies. Treatment continues to be based on cytotoxic chemotherapy regimens. However, characterization of the molecular pathway deregulations that drive these tumors has led to the emergence of more customized treatment options. In this review, we focus on the multitude of molecular inhibitors targeting angiogenesis and cell cycle pathways being tested in clinical trials.

Targeted treatment with pazopanib in metastatic soft tissue sarcoma: Nearly complete response in two cases

Soft tissue sarcomas (STS) are a group of rare mesenchymal cancers that include approximately 50 histological types and account for 1% of all adult cancers. The standard curative treatment option for localized disease is surgical resection and, if a surgically removed tumor exhibits high-risk characteristics, adjuvant chemotherapy and radiotherapy may be administered. Sarcoma presenting at an advanced stage has a dismal prognosis and survival has not markedly improved over the last 20 years. The standard first-line treatment for advanced STS, other than gastrointestinal stromal tumors, is cytotoxic chemotherapy. Therapies targeting pro-angiogenic factors have been a focus of drug development for STS over the last few years. Pazopanib, a multitargeted tyrosine kinase inhibitor, is a novel treatment option for patients with metastatic STS in the second-line setting. This is a presentation of 2 case reports of patients with metastatic STS who responded well to treatment with pazopanib.

The combination of intralymphatic chemotherapy with ultrasound and nano-/microbubbles is efficient in the treatment of experimental tumors in mouse lymph nodes

Intravenous chemotherapy is a therapeutic option for the treatment of lymph node metastasis, but the drugs often have difficulty accessing the lymphatic system. The aim of this study was to determine whether the combination of intralymphatic chemotherapy with ultrasound and nano-/microbubbles is active against tumors in mouse lymph nodes. Intralymphatic chemotherapy in mice with lymph nodes containing tumors was found to have a marked anti-tumor effect, compared with intravenous administration, and the addition of ultrasound combined with nano-/microbubbles enhanced the effect of the anti-cancer drug, but only when the drug was administered intralymphatically. Furthermore, decreases in the volumes and blood vessel densities of tumor-bearing lymph nodes are reliable measures of therapeutic effect, confirmed by histopathological evaluation. The main conclusion is that combining ultrasound with nano-/microbubbles and intralymphatic chemotherapy improves drug delivery to the lymphatic system and has a more potent anti-tumor effect.

Combined treatment of murine fibrosarcoma with chemotherapy (Paclitaxel), radiotherapy, and intratumoral injection of dendritic cells

Background

New antitumor therapeutic strategies aim to combine different approaches that are able to induce tumor-specific effector and memory T cell responses that might control tumor growth. Dendritic cells (DCs) have the capacity to induce antigen-specific cytotoxic T lymphocytes. We have previously shown that the combined treatment of paclitaxel chemotherapy (Chemo) and injection of DCs led to complete tumor regression.

Objective

The goal of this study was to evaluate synergistic antitumor effect of a triple combination treatment comprising radiotherapy, paclitaxel Chemo and intratumoral injection of syngeneic bone marrow-derived DCs on murine fibrosarcoma, compared to other single or double combination treatments.

Methods

For the murine fibrosarcoma model, naïve C57BL/6 mice were inoculated intradermally with 2×10³ MCA102 cells in the right upper flank. Mice were assigned to five groups (untreatedcontrol, RT alone, RT+Chemo, RT+DC, and RT+Chemo+DC), with eight mice in each group. In vitro cytotoxicity assays were performed to assess the immune activity. The persistence of tumor-specific immunity was determined by second tumor challenge in mice with complete tumor regression.

Results

The triple combination treatment showed a significantly enhanced therapeutic efficacy by decreasing tumor size and inducing complete tumor regression, resulting in a cure of 50% of mice. The results of in vitro cytotoxicity assays and the second tumor challenge experiment strongly indicated the induction of a tumor-specific cytotoxic T lymphocyte response and acquisition of prolonged tumor immunity.

Conclusion

These findings suggest that the triple combination treatment can be a promising strategy for the treatment of murine fibrosarcoma.

Efficacy and safety of pharmacological interventions in second- or later-line treatment of patients with advanced soft tissue sarcoma: a systematic review

BACKGROUND

Current guidelines recommend anthracycline-based chemotherapy primarily with doxorubicin either as monotherapy or in combination with ifosfamide as the first-line treatment for most advanced STS subtypes. Therapeutic options after failure of doxorubicin and/or ifosfamide are limited. This study aimed to comprehensively review available data on the activity and safety of interventions in second- or later-line treatment of advanced STS.

METHODS

Electronic literature databases (Embase®, MEDLINE®, MEDLINE® In-Process, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews) were searched from 1980 to 01 March 2012 to identify randomised controlled trials (RCTs) and non-randomised studies (both prospective and retrospective) evaluating pharmacological interventions in patients with advanced STS pre-treated with anthracycline- and/or ifosfamide-based therapy.

RESULTS

The review identified six RCTs (one phase III and five phase II trials) and 94 non-randomised studies. Based on the primary trial endpoints, RCTs demonstrated favourable efficacy for pazopanib over placebo (PFS: 4.6 months vs. 1.6 months), gemcitabine plus dacarbazine over dacarbazine monotherapy (3-month PFS rate: 54.2% vs. 35.2%), and trabectedin 3-weekly schedule over weekly schedule (TTP: 3.7 months vs. 2.3 months. The non-randomised studies demonstrated heterogeneity in efficacy and safety results.

CONCLUSIONS

Across the RCTs, pazopanib over placebo, gemcitabine-dacarbazine over dacarbazine, and trabectedin 3-weekly over weekly regimen clearly demonstrated a PFS advantage in the second- and later-line treatment of advanced STS. With only one phase III trial in this setting, there is a clear need for additional comparative trials to better understand the risk: benefit ratios of available agents and combinations.

'Decoy' and 'non-decoy' functions of DcR3 promote malignant potential in human malignant fibrous histiocytoma cells

Decoy receptor 3 (DcR3) is a soluble secreted protein that belongs to the tumor necrosis factor receptor (TNFR) superfamily. DcR3 inhibits the Fas ligand (FasL)/Fas apoptotic pathway by binding to FasL, competitively with Fas receptor. Previous studies have reported that overexpression of DcR3 has been detected in various human malignancies and that DcR3 functions as a ‘decoy’ for FasL to inhibit FasL-induced apoptosis. In addition, recent studies have revealed that DcR3 has ‘non-decoy’ functions to promote tumor cell migration and invasion, suggesting that DcR3 may play important roles in tumor progression by decoy and non-decoy functions. We have previously reported that overexpression of DcR3 was observed in human malignant fibrous histiocytoma (MFH), however, the roles of DcR3 in MFH have not been studied. In the present study, to elucidate the roles of DcR3 in tumor progression of MFH, we examined the effects of DcR3 inhibition on cell apoptosis, migration and invasion in human MFH cells. siRNA knockdown of DcR3 enhanced the FasL-induced apoptotic activity and significantly decreased cell migration and invasion with a decrease in the activation of phosphatidylinositol 3 kinase (PI3K)/Akt and matrix metalloproteinase (MMP)-2. The findings in this study strongly suggest that DcR3 plays important roles in tumor progression of human MFH by decoy as well as non-decoy functions and that DcR3 may serve as a potent therapeutic target for human MFH.

Dendritic cell immunotherapy in soft tissue sarcoma

Soft tissue sarcomas represent a rare but diverse family of tumors affecting patients of all ages. Conventional chemotherapy rarely eradicates metastatic disease and newer targeted agents are successful in only very specific histologic subgroups. Therefore, scientists and clinicians are investigating immunotherapy techniques, primarily involving cellular immunity focused on the T-cell response to tumor antigens. In both animal models and human sarcoma trials, dendritic cells have been shown to induce an effective antitumor immune response. Radiotherapy, particularly when delivered in a hypofractionated manner prior to sarcoma excision, may potentiate the function of the dendritic cells through the induction of apoptosis. The synergistic effect may carry over to other cancer types and warrants further multidisciplinary investigation.

Anticancer activity of stabilized palifosfamide in vivo: schedule effects, oral bioavailability, and enhanced activity with docetaxel and doxorubicin

Palifosfamide, the DNA-alkylating metabolite of ifosfamide (IFOS), has been synthesized as a stabilized tris or lysine salt and found to have preclinical and clinical antitumor activity. Stabilized palifosfamide overcomes limitations of IFOS because of patient-to-patient variability in response resulting from variable prodrug activation, resistance and toxicities of metabolic byproducts, acrolein and chloroacetaldehyde. Palifosfamide represents an effective alternative to IFOS and other DNA-alkylating prodrugs. The antitumor activities of stabilized palifosfamide were investigated in vivo. Dose response, route and schedule of administration, and interaction with docetaxel or doxorubicin were investigated in NCr-nu/nu mice bearing established orthotopic mammary MX-1 tumor xenografts. Oral activity was investigated in P388-1 leukemia in CD2F1 mice. Oral and intraperitoneal bioavailabilities were compared in Sprague-Dawley rats. Stabilized palifosfamide administered by optimized regimens suppressed MX-1 tumor growth (P<0.05) by greater than 80% with 17% complete antitumor responses and up to three-fold increase in time to three tumor doublings over controls. Median survival in the P388-1 (P<0.001) model was increased by 9 days over controls. Oral bioavailability in rats was 48-73% of parenteral administration, and antitumor activity in mice was equivalent by both routes. Treatment with palifosfamide-tris combined with docetaxel or doxorubicin at optimal regimens resulted in complete tumor regression in 62-75% of mice. These studies support investigation of stabilized palifosfamide in human cancers by parenteral or oral administration as a single agent and in combination with other approved drugs. The potential for clinical translation of the cooperative interaction of palifosfamide-tris with doxorubicin by intravenous administration is supported by results from a recent randomized Phase-II study in unresectable or metastatic soft-tissue sarcoma.

A phase II study of tasisulam sodium (LY573636 sodium) as second-line or third-line treatment for patients with unresectable or metastatic soft tissue sarcoma

BACKGROUND

Tasisulam sodium (hereafter tasisulam), a novel anticancer agent, is being studied in a broad range of tumors. The primary objective of this phase II study was to determine progression-free survival (PFS) in patients with 1 or 2 prior chemotherapy regimens for unresectable/metastatic soft tissue sarcoma (STS). Secondary objectives included objective response rate (ORR), clinical benefit rate (CBR), overall survival (OS), pharmacokinetics, and safety.

METHODS

Tasisulam was administered intravenously on day 1 of 21-day cycles according to a lean body weight-based dosing algorithm targeting a peak plasma concentration (C(max)) of 420 μg/mL; a 360-μg/mL dose level was also explored.

RESULTS

The median age of patients treated at 420 μg/mL was 58.3 years (range, 18.6-80.4; n = 63). Median PFS was 2.64 months (90 % CI, 1.41-3.38), with a 6-month PFS rate of 11 % (90 % CI, 4-17). Median OS was 8.71 months (90 % CI, 7.39-16.23); ORR, 3.2 %; and CBR, 46.0 % (stable disease, n = 27; partial response/confirmed, n = 2 [angiosarcoma and leiomyosarcoma]; partial response/unconfirmed, n = 1 [desmoplastic small round cell tumor]). The most frequent drug-related grade 3/4 toxicities in patients treated at 420 μg/mL were thrombocytopenia (27.0 %) and neutropenia (22.2 %). Incidences of grade 4 thrombocytopenia and/or neutropenia were 20.6 % in patients treated at 420 μg/mL and 15.8 % in those treated at 360 μg/mL (n = 38).

CONCLUSIONS

Tasisulam at a target C(max) of 420 μg/mL on day 1 of 21-day cycles demonstrated modest activity as second-/third-line treatment in patients with STS. Grade 4 hematologic toxicity posed some challenges in these heavily pre-treated patients. Tasisulam dosing continues to be refined.

Combination of external beam radiotherapy (EBRT) with intratumoral injection of dendritic cells as neo-adjuvant treatment of high-risk soft tissue sarcoma patients

PURPOSE

The goal of this study was to determine the effect of combination of intratumoral administration of dendritic cells (DC) and fractionated external beam radiation (EBRT) on tumor-specific immune responses in patients with soft-tissue sarcoma (STS).

METHODS AND MATERIAL

Seventeen patients with large (>5 cm) high-grade STS were enrolled in the study. They were treated in the neoadjuvant setting with 5,040 cGy of EBRT, split into 28 fractions and delivered 5 days per week, combined with intratumoral injection of 10(7) DCs followed by complete resection. DCs were injected on the second, third, and fourth Friday of the treatment cycle. Clinical evaluation and immunological assessments were performed.

RESULTS

The treatment was well tolerated. No patient had tumor-specific immune responses before combined EBRT/DC therapy; 9 patients (52.9%) developed tumor-specific immune responses, which lasted from 11 to 42 weeks. Twelve of 17 patients (70.6%) were progression free after 1 year. Treatment caused a dramatic accumulation of T cells in the tumor. The presence of CD4(+) T cells in the tumor positively correlated with tumor-specific immune responses that developed following combined therapy. Accumulation of myeloid-derived suppressor cells but not regulatory T cells negatively correlated with the development of tumor-specific immune responses. Experiments with (111)In labeled DCs demonstrated that these antigen presenting cells need at least 48 h to start migrating from tumor site.

CONCLUSIONS

Combination of intratumoral DC administration with EBRT was safe and resulted in induction of antitumor immune responses. This suggests that this therapy is promising and needs further testing in clinical trials design to assess clinical efficacy.