The clinicopathological analysis of receptor tyrosine kinases in meningiomas: the expression of VEGFR-2 in meningioma was associated with a higher WHO grade and shorter progression-free survival

A Review of FDA-Approved Multi-Target Angiogenesis Drugs for Brain Tumor Therapy

Neovascularization is an important process in brain tumor development, invasion and metastasis. Several research studies have indicated that the VEGF signaling target has potential for reducing angiogenesis in brain tumors. However, targeting VEGF signaling has not met the expected efficacy, despite initial enthusiasm. This is partly because tumors cleverly use alternative growth factor pathways, other than VEGF signaling, to restore angiogenesis. Multi-target inhibitors have been developed to inhibit several receptor kinases that play a role in the development of angiogenesis. By simultaneously affecting various receptor kinases, these treatments can potentially obstruct various angiogenic pathways that are involved in brain cancer advancement, often offering a more holistic strategy than treatments focusing on just one kinase. Since 2009, the FDA has approved a number of multi-kinase inhibitors that target angiogenic growth factor receptors (e.g., VEGFR, PDGFR, FGFR, RET, c-KIT, MET, AXL and others) for treatment of malignant diseases, including brain cancer. Here, we present some recent results from the literature regarding the preclinical and clinical effects of these inhibitors on brain tumors.

Molecular diagnosis and treatment of meningiomas: an expert consensus (2022)

ABSTRACT

Meningiomas are the most common primary intracranial neoplasm with diverse pathological types and complicated clinical manifestations. The fifth edition of the WHO Classification of Tumors of the Central Nervous System (WHO CNS5), published in 2021, introduces major changes that advance the role of molecular diagnostics in meningiomas. To follow the revision of WHO CNS5, this expert consensus statement was formed jointly by the Group of Neuro-Oncology, Society of Neurosurgery, Chinese Medical Association together with neuropathologists and evidence-based experts. The consensus provides reference points to integrate key biomarkers into stratification and clinical decision making for meningioma patients.

REGISTRATION

Practice guideline REgistration for transPAREncy (PREPARE), IPGRP-2022CN234.

Receptor-Tyrosine Kinase Inhibitor Ponatinib Inhibits Meningioma Growth In Vitro and In Vivo

To date, there is no standard-of-care systemic therapy for the treatment of aggressive meningiomas. Receptor tyrosine kinases (RTK) are frequently expressed in aggressive meningiomas and are associated with poor survival. Ponatinib is a FDA- and EMA-approved RTK inhibitor and its efficacy in meningioma has not been studied so far. Therefore, we investigated ponatinib as a potential drug candidate against meningioma. Cell viability and cell proliferation of ponatinib-treated meningioma cells were assessed using crystal violet assay, manual counting and BrdU assay. Treated meningioma cell lines were subjected to flow cytometry to evaluate the effects on cell cycle and apoptosis. Meningioma-bearing mice were treated with ponatinib to examine antitumor effects in vivo. qPCR was performed to assess the mRNA levels of tyrosine kinase receptors after ponatinib treatment. Full-length cDNA sequencing was carried out to assess differential gene expression. IC50 values of ponatinib were between 171.2 and 341.9 nM in three meningioma cell lines. Ponatinib induced G0/G1 cell cycle arrest and subsequently led to an accumulation of cells in the subG1-phase. A significant induction of apoptosis was observed in vitro. In vivo, ponatinib inhibited meningioma growth by 72.6%. Mechanistically, this was associated with downregulation of PDGFRA/B and FLT3 mRNA levels, and mitochondrial dysfunction. Taken together, ponatinib is a promising candidate for targeted therapy in the treatment of aggressive meningioma.

Receptor Tyrosine Kinases as Candidate Prognostic Biomarkers and Therapeutic Targets in Meningioma

Meningioma (MGM) is the most common type of intracranial tumor in adults. The validation of novel prognostic biomarkers to better inform tumor stratification and clinical prognosis is urgently needed. Many molecular and cellular alterations have been described in MGM tumors over the past few years, providing a rational basis for the identification of biomarkers and therapeutic targets. The role of receptor tyrosine kinases (RTKs) as oncogenes, including those of the ErbB family of receptors, has been well established in several cancer types. Here, we review histological, molecular, and clinical evidence suggesting that RTKs, including the epidermal growth factor receptor (EGFR, ErbB1), as well as other members of the ErbB family, may be useful as biomarkers and therapeutic targets in MGM.

Influence of VEGF-A, VEGFR-1-3, and neuropilin 1-2 on progression-free: and overall survival in WHO grade II and III meningioma patients

Higher grade meningiomas tend to recur. We aimed to evaluate protein levels of vascular endothelial growth factor (VEGF)-A with the VEGF-receptors 1-3 and the co-receptors Neuropilin (NRP)-1 and -2 in WHO grade II and III meningiomas to elucidate the rationale for targeted treatments. We investigated 232 specimens of 147 patients suffering from cranial meningioma, including recurrent tumors. Immunohistochemistry for VEGF-A, VEGFR-1-3, and NRP-1/-2 was performed on tissue micro arrays. We applied a semiquantitative score (staining intensity x frequency). VEGF-A, VEGFR-1-3, and NRP-1 were heterogeneously expressed. NRP-2 was mainly absent. We demonstrated a significant increase of VEGF-A levels on tumor cells in WHO grade III meningiomas (p = 0.0098). We found a positive correlation between expression levels of VEGF-A and VEGFR-1 on tumor cells and vessels (p < 0.0001). In addition, there was a positive correlation of VEGF-A and VEGFR-3 expression on tumor vessels (p = 0.0034). VEGFR-2 expression was positively associated with progression-free survival (p = 0.0340). VEGF-A on tumor cells was negatively correlated with overall survival (p = 0.0084). The VEGF-A-driven system of tumor angiogenesis might still present a suitable target for adjuvant therapy in malignant meningioma disease. However, its role in malignant tumor progression may not be as crucial as expected. The value of comprehensive testing of the ligand and all receptors prior to administration of anti-angiogenic therapy needs to be evaluated in clinical trials.

Apatinib in recurrent anaplastic meningioma: a retrospective case series and systematic literature review

Up to now, no proven effective medical therapy for surgery and radiation-refractory anaplastic meningioma (AM) exists. Patients with vascular endothelial growth factor receptor 2 (VEGFR-2) positive meningiomas showed significantly shorter progression-free survival. Apatinib is a small-molecule antiangiogenic agent that selectively inhibits VEGFR-2. We report three cases of recurrent AM (VEGFR-2 positive) treated with apatinib. After apatinib treatment, the best outcome for all three patients was the partial response. The Progression-free survival was 17.3 months, 10.3 months, and 14+ months, respectively. The third patient lost follow-up after the last review. The overall survival was 28.5 months and 18 months, respectively. The main adverse events were hypertension, hand-foot syndrome, and myelosuppression. Apatinib is active in recurrent AM patients and this is the first report in the world. It is promising to launch a Phase II clinical trial of apatinib to further evaluate its efficacy on AM.

BACKGROUND

Anaplastic meningioma (AM) are rare and aggressive tumors with high recurrence rates despite optimal surgical or medical management. Up to now, no proven effective medical therapy, surgery, or radiation-refractory for AM exist. The progression-free survival (PFS) of patients with vascular endothelial growth factor receptor 2 (VEGFR-2)-positive meningiomas was significantly low. Apatinib (YN968D1) is a small-molecule antiangiogenic agent that selectively inhibits VEGFR-2.

CASE PRESENTATION

CASE #1

A 47-year-old Asian female patient with malignant meningioma underwent four operations and three radiotherapies. She was given a 500 mg apatinib daily oral treatment, and the dosage was halved to 250 mg 3 months into the treatment. According to the Response Assessment in Neuro-Oncology (RANO) evaluation criteria, the best outcome during treatment was the partial response (PR) 6 months after the treatment. The PFS was 17.3 months, whereas the overall survival (OS) was 28.5 months. The best change in the Karnofsky performance scale (KPS) was a 10-point increase. The main adverse events included anemia (grade II), thrombocytopenia (grade II), and proteinuria (grade I).

CASE #2

A 71-year-old Asian woman with AM underwent two operations and two gamma knife stereotactic radiotherapies. She was given a 500 mg apatinib daily oral treatment with a follow-up period of 18 months. apatinib was taken orally for 10 months. According to the RANO evaluation criteria, the best outcome during treatment was PR. The PFS was 10.3 months, whereas the OS was 18 months. The best change in KPS was a 20-point increase. The main adverse events included hypertension (grade II), hand-foot syndrome (grade II), and fecal ocular blood (grade II). Case #3: A 16-year-old Asian girl with AM underwent two operations and two radiotherapies. She was given a 250 mg apatinib daily oral treatment with a follow-up period of 16 months. Apatinib was taken orally for 8 months. The patient did not follow-up after the last review of the brain-enhanced magnetic resonance imaging. According to the RANO evaluation criteria, the best outcome during treatment was PR. The PFS was 14+ months, and the best change in KPS was a 10-point increase. The main adverse events included hypertension (grade I) and hand-foot syndrome (grade I).

CONCLUSION

Apatinib is actively used in treating patients with recurrent AM. A randomized trial and phase II clinical trial of this inhibitor should be performed to further evaluate its efficacy in treating malignant meningioma.