Pazopanib for metastatic soft-tissue sarcoma: A multicenter retrospective study

Fragment-based investigation of thiourea derivatives as VEGFR-2 inhibitors: a cross-validated approach of ligand-based and structure-based molecular modeling studies

Angiogenesis is mediated by the vascular endothelial growth factor (VEGF) that plays a key role in the modulation of progression, invasion and metastasis, related to solid tumors and hematological malignancies. Several small-molecule VEGFR-2 inhibitors are marketed, but their usage is restricted to specific cancers due to severe toxicities. Therefore, cost-effective novel small molecule VEGFR-2 inhibitors may be an alternative to overcome these adverse effects. Here, a set of thiourea-based VEGFR-2 inhibitors were considered for a combined fragment-based QSAR technique, structure-based molecular docking followed by molecular dynamics simulation studies to acquire insights into the key structural attributes and the binding pattern of enzyme-ligand interactions. Noticeably, amine-substituted quinazoline phenyl ring and a higher number of nitrogen atoms, and the hydrazide function in the molecular structure are crucial for VEGFR-2 inhibition whereas methoxy groups are detrimental to VEGFR-2 inhibition. The MD simulation study of sorafenib and thiourea derivatives explored the significance of urea and thiourea moiety binding at VEGFR-2 active site that can be utilized further in the future to design molecules for greater binding stability and better VEGFR-2 selectivity. Therefore, such findings can be beneficial for the development of newer VEGFR-2 inhibitors for further refinement to acquire better therapeutic efficacy.Communicated by Ramaswamy H. Sarma.

Changing landscape of anti-angiogenic therapy: Novel approaches and clinical perspectives

Targeting angiogenesis has remained one of the important aspects in disease biology in general and cancer in particular. Currently (June 2023), over 593 clinical trials have been registered at ClinicalTrials.gov having inference of term 'angiogenesis'. A panel of 14 anti-angiogenic drugs have been approved by FDA for the treatment of variety of cancers and other human ailments. Although the anti-angiogenic therapy (AAT) has gained significant clinical attention as a promising approach in the treatment of various diseases, particularly cancer, however, sizable literature has accumulated in the recent past describing the aggressive nature of tumours after the drug holidays, evolving drug resistance and off-target toxicities. Nevertheless, the emergence of inscrutable compensatory or alternative angiogenic mechanisms is limiting the efficacy of anti-angiogenic drugs and focussing the therapeutic regime as a puzzle of 'Lernaean hydra'. This review offers an overview of recent updates on the efficacy of antiangiogenic therapy and the current clinical performance of aaRTK inhibitors. Additionally, it also explores the changing application landscape of AAT, focusing on its role in diabetic nephropathy, age-related macular degeneration and other neovascular ocular disorders. Combination therapy with antiangiogenic drugs and immune check point inhibitors (ICIs) has emerged as a potential strategy to enhance the therapeutic index of cancer immunotherapy. While clinical studies have demonstrated the clinical efficacy of this approach, they also highlight the complex and sometimes unpredictable adverse events associated with it. Normalizing tumour vasculature has been identified as a key factor in unlocking the full potential of ICIs, thereby providing hope for improved treatment outcomes. The future prospects and challenges of AAT have been described with special reference to integration of technological advances for enhancing its efficacy and applications beyond its discovery.

Real-world outcomes of pazopanib in metastatic soft tissue sarcoma: a retrospective Turkish oncology group (TOG) study

AIM

Description of patient characteristics, effectiveness and safety in Turkish patients treated with pazopanib for metastatic soft tissue sarcoma (STS).

PATIENTS AND METHODS

This multicenter study is based on retrospective review of hospital medical records of patients (≥ 18 years) treated with pazopanib for non-adipocytic metastatic STS at 37 Oncology clinics across Turkey. Objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS) and overall survival (OS) were evaluated with further analysis of data on the three most common histological subtypes (leiomyosarcoma [LMS], undifferentiated pleomorphic sarcoma [UPS], synovial sarcoma [SS]) in the cohort.

RESULTS

Data of 552 adults (57.6% women, median age: 52 years) were analyzed. DCR and ORR were 43.1% and 30.8%, respectively. Median PFS was 6.7 months and OS was 13.8 months. For LMS, UPS and SS, median PFSs were 6.1, 5.9 and 7.53 months and median OSs were 15.03, 12.87 and 12.27 months, respectively. ECOG ≥ 2 was associated with poor PFS and OS. Liver metastasis was only a factor for progression. Second-line use of pazopanib (vs. front-line) was associated with better PFS, its use beyond third line predicted worse OS. Adverse events (AE) occurred in 82.7% of patients. Most common AEs were fatigue (58.3%) and anorexia (52.3%) which were graded as ≥ 3 in 8.2% and 7.4% of patients, respectively.

CONCLUSION

Pazopanib is effective and well-tolerated in treatment of non-adipocytic metastatic STS. Its earlier use (at second-line), good performance status may result in better outcomes. Worldwide scientific collaborations are important to gain knowledge on rarer STS subtypes by conducting studies in larger patient populations.

Stewart-Treves syndrome: a case report of lymphedema-related angiosarcoma

Stewart-Treves syndrome (STS) is an angiosarcoma associated with lymphedema deriving more often from radical mastectomy and longstanding lymphedema, first described in 1948. Irradiation is also commonly associated with chronic lymphedema of extremities. It generally occurs about 10 years after the mastectomy and/or radiotherapy. The prognosis is very poor with a mean survival of 20 months from the diagnosis especially when radical surgery is not possible. We present the case of STS in an 89-year-old female who underwent left upper outer quadrantectomy for invasive ductal carcinoma in 2009 followed by axillary lymphadenectomy, radiotherapy, and hormonal therapy until 2014. She presented swollen upper left limb associated with hemorrhagic red papular lesions. Skin biopsy revealed the presence of lymphedema-associated angiosarcoma. Radical surgery was not possible, so she underwent conservative therapy with pazopanib, a tyrosine kinase inhibitor, with benefit. Long-term follow-up of these patients is crucial to intercept this condition at an early stage.

Design, synthesis and biological characteristics of pyrazolo[3,4-d]pyrimidine derivatives as potential VEGFR-2 inhibitors

Aim: Several VEGFR-2 inhibitors with the structure of [3,4-d]pyrimidine and based on sorafenib were designed and synthesized. Materials & methods: Cytotoxic activity was evaluated by MTT, wound healing and clone formation assays. Cell cycle and apoptosis were analyzed by flow cytometry. Molecular simulation and western blot were also applied. Results: Among them, II-1 significantly inhibited tumor cellular activity (IC₅₀ = 5.90 ± 0.05 μM on HepG2 cells) compared with sorafenib (IC₅₀ = 9.05 ± 0.54 μM on HepG2 cells). Molecular docking demonstrated that II-1 and sorafenib have the same hydrogen binding. Finally, the protein expression of phosphorylated VEGFR-2 was substantially reduced after II-1 treatment. Conclusion: Compound II-1 can inhibit VEFGR-2 activation and is an effective antitumor agent in liver cancer cells.

Real-World Outcome and Prognostic Factors of Pazopanib in Advanced Soft Tissue Sarcoma

Purpose

Pazopanib has been approved for treating soft tissue sarcomas (STS) after chemotherapy. We aimed to evaluate the prognostic factors, clinical outcomes, and tolerability of pazopanib in patients with STS.

Patients and Methods

Forty-five patients treated between June 2015 and August 2019 were reviewed. Clinical outcome was measured by assessing the disease control rate (DCR) using Response Evaluation Criteria in Solid Tumors (version 1.1). Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan–Meier method. Adverse effects were assessed using the Common Terminology Criteria for Adverse Events (version 5.0).

Results

The median age of patients at diagnosis was 28 (interquartile range (IQR), 23–45) years. Pazopanib was used as the second-line treatment in 46.7% and the subsequent line in 53.3% of patients. The overall DCR was 55.6%, and at 8 and 12 weeks, it was 52.3% and 35.5%, respectively; the median duration of response was 7 (IQR: 2–18) months. Pazopanib-induced hypothyroidism was associated with DCR, with an odds ratio of 7 (95% confidence interval [95% CI: 1.7–27.5], p<0.01). The median PFS and OS were 4.1 (95% CI: 0.85–7.42) and 12.4 months (95% CI: 6.5–18.36), respectively. Hypothyroidism and response to pazopanib, better ECOG PS, histological subtypes desmoid tumor/aggressive fibromatosis (DT/AF), and alveolar soft part sarcoma (ASPS) were favorable prognostic factors for PFS. Hypothyroidism and response to pazopanib were significant favorable factors for OS. There was no statistical difference in the OS between patients using pazopanib as the second-line therapy and those using it as the subsequent-line therapy.

Conclusion

Pazopanib is an effective treatment for STS. However, it showed variability in the clinical outcome in favor of ASPS and an outstanding response in the DT/AF subtype. Pazopanib-induced hypothyroidism is a good prognostic factor for disease control and is associated with prolonged PFS and OS.