Temozolomide-related hematologic toxicity

Engineered nanovesicles targeting SERPINE1 overcome temozolomide resistance in glioblastoma

Glioblastoma multiforme (GBM) is a highly aggressive brain tumor with limited treatment options due to its resistance to temozolomide (TMZ). This study explores a novel therapeutic approach using engineered cell membrane nanovesicles loaded with SERPINE1 inhibitors to combat TMZ resistance. High-throughput sequencing identified pivotal genes associated with resistance, while the nanovesicles demonstrated excellent stability and the ability to cross the blood-brain barrier. Functional assays revealed significant suppression of GBM cell viability, migration, and invasion, accompanied by reduced expression of SERPINE1 and VEGF, suggesting inhibition of angiogenesis and tumor progression. These findings highlight the potential of SERPINE1-targeted nanovesicles as an innovative and effective strategy for overcoming TMZ resistance in GBM.

Levetiracetam and valproic acid in glioma: antiseizure and potential antineoplastic effects

Seizures are a frequent complication in glioma. Incidence of brain tumor-related epilepsy (BTRE) in high-grade glioma (HGG) is an estimated > 25% and in low-grade glioma (LGG) is approximately 72%. Two first-line antiseizure medications (ASMs) for BTRE include levetiracetam (LEV) and valproic acid (VPA). Use of VPA has decreased because of a broader side effect profile, potential interaction with chemotherapeutic drugs, and availability of newer generation agents. In refractory BTRE, LEV and VPA may be prescribed together to enhance seizure control. VPA and LEV have gained attention for their purported antineoplastic effects and synergistic role with temozolomide. VPA is suggested to modulate anticancer activity in vitro through multiple mechanisms. In addition, retrospective studies indicate increased overall survival in patients with epileptogenic HGGs who are managed with LEV or VPA rather than other ASMs. However, these studies have numerous limitations. It is also reported that patients with glioma and a seizure history have a longer survival. This extended survival, if one exists, may be only observed in certain gliomas with corresponding patient characteristics. We provide a brief overview of the management of BTRE, VPA and LEV as anticonvulsants and antineoplastics, and the factors that may be associated with survival in epileptogenic glioma.

Post-Marketing Safety of Temozolomide: A Pharmacovigilance Study Based on the Food and Drug Administration Adverse Event Reporting System

INTRODUCTION

Temozolomide (TMZ) is a widely used chemotherapy agent for the treatment of malignant gliomas and other brain tumors. Despite its established therapeutic benefits, there is an ongoing need to understand better its safety profile, particularly in real-world clinical settings. This study aimed to identify critical adverse drug reactions (ADRs) associated with TMZ by utilizing the FDA Adverse Event Reporting System (FAERS) database, thereby providing valuable safety insights for clinical practice.

METHODS

We utilized the reported odds ratio, proportional reporting ratio, Bayesian Confidence Propagation Neural Network, and Empirical Bayes Geometric Mean as primary algorithms for disproportionality analysis. Adverse events (AEs) were classified as ADRs only upon meeting the criteria set by all four algorithms. To ensure the accuracy of our results, we meticulously excluded any AEs deemed unrelated to TMZ.

RESULTS

From October 2003 to September 2023, a total of 10,502,538 case reports and 9,073 cases explicitly attributed to TMZ were retrieved from the FAERS database. After applying our filters, 116 ADRs, each with a corresponding Preferred Term (PT), were identified across 18 System Organ Classes (SOCs). The identified ADRs associated with TMZ primarily involved bone marrow suppression, hepatotoxicity, and various infections, notably Pneumocystis jirovecii pneumonia. Furthermore, our analysis identified valuable ADRs not listed in the drug label, including congenital, familial, and genetic disorders at the SOC level, as well as unexpected ADRs at the PT level, such as seizures, pulmonary embolism, and sepsis.

CONCLUSION

This real-world pharmacovigilance study has identified significant and previously unreported ADRs associated with TMZ. Further research for validation and resolution is urgently needed to guide the clinical application of TMZ, ensuring the safety and efficacy of its use in treating brain tumors.

Enhancing glioma treatment with 3D scaffolds laden with upconversion nanoparticles and temozolomide in orthotopic mouse model

Targeted drug delivery for primary brain tumors, particularly gliomas, is currently a promising approach to reduce patient relapse rates. The use of substitutable scaffolds, which enable the sustained release of clinically relevant doses of anticancer medications, offers the potential to decrease the toxic burden on the patient's organism while also enhancing their quality of life and overall survival. Upconversion nanoparticles (UCNPs) are being actively explored as promising agents for detection and monitoring of tumor growth, and as therapeutic agents that can provide isolated therapeutic effects and enhance standard chemotherapy. Our study is focused on the feasibility of constructing scaffolds using methacrylated hyaluronic acid with additional impregnation of UCNPs and the chemotherapeutic drug temozolomide (TMZ) for glioma treatment. The designed scaffolds have been demonstrated their efficacy as a drug and UCNPs delivery system for gliomas. Using the aggressive orthotopic glioma model in vivo, it was found that the scaffolds possess the capacity to ameliorate neurological disorders in mice. Moreover, upon intracranial co-implantation of the scaffolds and glioma cells, the constructs disintegrate into distinct segments, augmenting the release of UCNPs into the surrounding tissue and concurrently reducing postoperative damage to brain tissue. The use of TMZ in the scaffold composition contributed to restraining glioma development and the reduction of tumor invasiveness. Our findings unveil promising prospects for the application of photopolymerizable biocompatible scaffolds in the realm of neuro-oncology.

Prolonged use of temozolomide leads to increased anxiety and decreased content of aggrecan and chondroitin sulfate in brain tissues of aged rats

Chemotherapy with temozolomide (TMZ) is an essential part of anticancer therapy used for malignant tumors (mainly melanoma and glioblastoma); however, the long-term effects on patient health and life quality are not fully investigated. Considering that tumors often occur in elderly patients, the present study was conducted on long-term (4 months) treatment of adult Wistar rats (9 months old, n=40) with TMZ and/or dexamethasone (DXM) to investigate potential behavioral impairments or morphological and molecular changes in their brain tissues. According to the elevated plus maze test, long-term use of TMZ affected the anxiety of the adult Wistar rats, although no significant deterioration of brain morphology or cellular composition of the brain tissue was revealed. The expression levels of all studied heparan sulfate (HS) proteoglycans (HSPGs) (syndecan-1, syndecan-3, glypican-1 and HSPG2) and the majority of the studied chondroitin sulfate (CS) proteoglycans (CSPGs) (decorin, biglycan, lumican, brevican, neurocan aggrecan, versican, Cspg4/Ng2, Cspg5 and phosphacan) were not affected by TMZ/DXM, except for neurocan and aggrecan. Aggrecan was the most sensitive proteoglycan to TMZ/DXM treatment demonstrating downregulation of its mRNA and protein levels following TMZ (-10-fold), DXM (-45-fold) and TMZ-DXM (-80-fold) treatment. HS content was not affected by TMZ/DXM treatment, whereas CS content was decreased 1.5-2.5-fold in the TMZ- and DXM-treated brain tissues. Taken together, the results demonstrated that treatment of adult Wistar rats with TMZ had long-term effects on the brain tissues, such as decreased aggrecan core protein levels and CS chain content and increased anxiety of the experimental animals.

Research progress on the role of the Wnt signaling pathway in pituitary adenoma

Pituitary adenoma (PA) is the third most common central nervous system tumor originating from the anterior pituitary, but its pathogenesis remains unclear. The Wnt signaling pathway is a conserved pathway involved in cell proliferation, Self-renewal of stem cells, and cell differentiation. It is related to the occurrence of various tumors, including PA. This article reviews the latest developments in Wnt pathway inhibitors and pathway-targeted drugs. It discusses the possibility of combining Wnt pathway inhibitors with immunotherapy to provide a theoretical basis for the combined treatment of PA.

Glioblastoma Multiforme: The Latest Diagnostics and Treatment Techniques

BACKGROUND

Glioblastoma multiforme (GBM) is a WHO grade 4 glioma and the most common malignant primary brain tumour. Recently, there has been outstanding progress in the treatment of GBM. In addition to the newest form of GBM removal using fluorescence, three-dimensional (3D) imaging, tomoradiotherapy, moderate electro-hyperthermia, and adjuvant temozolomide (post-operative chemotherapy), new developments have been made in the fields of immunology, molecular biology, and virotherapy. An unusual and modern treatment has been created, especially for stage 4 GBM, using the latest therapeutic techniques, including immunotherapy and virotherapy. Modern oncological medicine is producing extraordinary and progressive therapeutic methods. Oncological therapy includes individual analysis of the properties of a tumour and targeted therapy using small-molecule inhibitors. Individualised medicine covers the entire patient (tumour and host) in the context of immunotherapy. An example is individualised multimodal immunotherapy (IMI), which relies on individual immunological tumour-host interactions. In addition, IMI is based on the concept of oncolytic virus-induced immunogenic tumour cell death.

SUMMARY

In this review, we outline current knowledge of the various available treatment options used in the therapy of GBM including both traditional therapeutic strategy and modern therapies, such as tomotherapy, electro-hyperthermia, and oncolytic virotherapy, which are promising treatment strategies with the potential to improve prognosis in patients with GBM.

KEY MESSAGES

This newest therapy, immunotherapy combined with virotherapy (oncolytic viruses and cancer vaccines), is displaying encouraging signs for combating GBM. Additionally, the latest 3D imaging is compared to conventional two-dimensional imaging.

Risk of cardiac-related death in astrocytoma patients treated with chemotherapy: A competing risk analysis using the SEER database

Purpose

To explore the impact of chemotherapy on the risk of cardiac-related death in astrocytoma patients.

Methods

We retrospectively evaluated astrocytoma patients diagnosed between 1,975 and 2016 in the Surveillance, Epidemiology, and End Results (SEER) database. Using Cox proportional hazards models, we compared the risks of cardiac-related death between a chemotherapy group and non-chemotherapy group. Competing-risks regression analyses were used to evaluate the difference in cardiac-related death. Also, propensity score matching (PSM) was employed to reduce confounding bias. The robustness of these findings was evaluated by sensitivity analysis, and E values were calculated.

Results

A total of 14,834 patients diagnosed with astrocytoma were included. Chemotherapy (HR = 0.625, 95%CI: 0.444-0.881) was associated with cardiac-related death in univariate Cox regression analysis. Chemotherapy was an independent prognostic factor for a lower risk of cardiac-related death before (HR = 0.579, 95%CI: 0.409-0.82, P = 0.002) and after PSM (HR = 0.550, 95%CI: 0.367-0.823 P = 0.004). Sensitivity analysis determined that the E-value of chemotherapy was 2.848 and 3.038 before and after PSM.

Conclusions

Chemotherapy did not increase the risk of cardiac-related death in astrocytoma patients. This study highlights that cardio-oncology teams should provide comprehensive care and long-term monitoring for cancer patients, especially those with an increased risk of cardiovascular disease.

Looking for the Holy Grail—Drug Candidates for Glioblastoma Multiforme Chemotherapy

Glioblastoma multiforme (GBM) is the deadliest and the most heterogeneous brain cancer. The median survival time of GBM patients is approximately 8 to 15 months after initial diagnosis. GBM development is determined by numerous signaling pathways and is considered one of the most challenging and complicated-to-treat cancer types. Standard GBM therapy consist of surgery followed by radiotherapy or chemotherapy, and combined treatment. Current standard of care (SOC) does not offer a significant chance for GBM patients to combat cancer, and the selection of available drugs is limited. For almost 20 years, there has been only one drug, Temozolomide (TMZ), approved as a first-line GBM treatment. Due to the limited efficacy of TMZ and the high rate of resistant patients, the implementation of new chemotherapeutics is highly desired. However, due to the unique properties of GBM, many challenges still need to be overcome before reaching a ‘breakthrough’. This review article describes the most recent compounds introduced into clinical trials as drug candidates for GBM chemotherapy.

Suppression of PI3K/Akt/mTOR pathway in chrysoeriol-induced apoptosis of rat C6 glioma cells

Chrysoeriol, a dietary methoxyflavonoid which is found in tropical medicinal plants, has been shown to have antioxidant, anti-inflammatory, and antineoplastic properties. The present study aimed to investigate the effects of chrysoeriol and its related mechanisms in rat C6 glioma cells. Cell viability in rat C6 glioma cells were measured by MTT assay. The protein expression levels of cleaved caspase-3, caspase-3, pro-apoptotic (Bax), anti-apoptotic protein (Bcl-2), and Annexin V were detected by Western blot analysis and immunocytochemical staining. Results showed that chrysoeriol significantly decreased cell viability and induced apoptosis in rat C6 glioma cells. Chrysoeriol significantly increased the levels of Bax/Bcl-2 ratio and cleaved caspase-3/caspase-3 ratio. Moreover, treatment with chrysoeriol significantly reduced the phosphorylation of PI3K, Akt, and mTOR expression in ratios. These results suggest that chrysoeriol promote apoptosis in rat C6 glioma cells via suppression of the PI3K/Akt/mTOR signaling pathway, thereby demonstrating the potential antineoplastic effects of chrysoeriol on glioma cells.

The Prognostic Value of NANO Scale Assessment in IDH-Wild-Type Glioblastoma Patients

Background

IDH-wild-type glioblastoma (GBM) is the most frequent brain-derived malignancy. Despite intense research efforts, it is still associated with a very poor prognosis. Several parameters were identified as prognostic, including general physical performance. In neuro-oncology (NO), special emphasis is put on focal deficits and cognitive (dys-)function. The Neurologic Assessment in Neuro-Oncology (NANO) scale was proposed in order to standardize the assessment of neurological performance in NO. This study evaluated whether NANO scale assessment provides prognostic information in a standardized collective of GBM patients.

Methods

The records of all GBM patients treated between 2014 and 2019 at our facility were retrospectively screened. Inclusion criteria were age over 18 years, at least 3 months postoperative follow-up, and preoperative and postoperative cranial magnetic resonance imaging. The NANO scale was assessed pre- and postoperatively as well as at 3 months follow-up. Univariate and multivariate survival analyses were carried to investigate the prognostic value.

Results

One hundred and thirty-one patients were included. In univariate analysis, poor postoperative neurological performance (HR 1.13, p = 0.004), poor neurological performance at 3 months postsurgery (HR 1.37, p < 0.001), and neurological deterioration during follow-up (HR 1.38, p < 0.001), all assessed via the NANO scale, were associated with shorter survival. In multivariate analysis including other prognostic factors such as the extent of resection, adjuvant treatment regimen, or age, NANO scale assessment at 3 months postoperative follow-up was independently associated with survival prediction (HR 1.36, p < 0.001). The optimal NANO scale cutoff for patient stratification was 3.5 points.

Conclusion

Neurological performance assessment employing the NANO scale might provide prognostic information in patients suffering from GBM.

Potentially Curative Therapeutic Activity of NEO212, a Perillyl Alcohol-Temozolomide Conjugate, in Preclinical Cytarabine-Resistant Models of Acute Myeloid Leukemia

Simple Summary

Many patients are still dying from acute myeloid leukemia (AML). Initial treatment of this blood-borne cancer consists of chemotherapy, usually with the agent cytarabine (AraC). However, the cancer cells can become drug resistant and unresponsive to AraC, which complicates further treatment and worsens prognosis. More effective treatments are needed. We are developing a novel anticancer compound called NEO212. We investigated its AML-therapeutic potential with the use of AraC-resistant AML cells grown in culture and in mice implanted with such AML cells. We found that NEO212 effectively killed AML cells in culture. The majority of AML mice that received NEO212 treatment survived and thrived without signs of tumor recurrence. At the same time, NEO212 treatment did not result in any detectable side effects, showing that this drug was very well tolerated by these animals. We deem it worthwhile to further develop NEO212 toward its evaluation in AML patients, in particular in those where initial therapy with AraC has failed.

Abstract

Despite progress in the treatment of acute myeloid leukemia (AML), the clinical outcome remains suboptimal and many patients are still dying from this disease. First-line treatment consists of chemotherapy, which typically includes cytarabine (AraC), either alone or in combination with anthracyclines, but drug resistance can develop and significantly worsen prognosis. Better treatments are needed. We are developing a novel anticancer compound, NEO212, that was created by covalent conjugation of two different molecules with already established anticancer activity, the alkylating agent temozolomide (TMZ) and the natural monoterpene perillyl alcohol (POH). We investigated the anticancer activity of NEO212 in several in vitro and in vivo models of AML. Human HL60 and U937 AML cell lines, as well as different AraC-resistant AML cell lines, were treated with NEO212 and effects on cell proliferation, cell cycle, and cell death were investigated. Mice with implanted AraC-sensitive or AraC-resistant AML cells were dosed with oral NEO212, and animal survival was monitored. Our in vitro experiments show that treatment of cells with NEO212 results in growth inhibition via potent G2 arrest, which is followed by apoptotic cell death. Intriguingly, NEO212 was equally potent in highly AraC-resistant cells. In vivo, NEO212 treatment strikingly extended survival of AML mice and the majority of treated mice continued to thrive and survive without any signs of illness. At the same time, we were unable to detect toxic side effects of NEO212 treatment. All in all, the absence of side effects, combined with striking therapeutic activity even in an AraC-resistant context, suggests that NEO212 should be developed further toward clinical testing.

Developing a lncRNA Signature to Predict the Radiotherapy Response of Lower-Grade Gliomas Using Co-expression and ceRNA Network Analysis

BACKGROUND

Lower-grade glioma (LGG) is a type of central nervous system tumor that includes WHO grade II and grade III gliomas. Despite developments in medical science and technology and the availability of several treatment options, the management of LGG warrants further research. Surgical treatment for LGG treatment poses a challenge owing to its often inaccessible locations in the brain. Although radiation therapy (RT) is the most important approach in this condition and offers more advantages compared to surgery and chemotherapy, it is associated with certain limitations. Responses can vary from individual to individual based on genetic differences. The relationship between non-coding RNA and the response to radiation therapy, especially at the molecular level, is still undefined.

METHODS

In this study, using The Cancer Genome Atlas dataset and bioinformatics, the gene co-expression network that is involved in the response to radiation therapy in lower-grade gliomas was determined, and the ceRNA network of radiotherapy response was constructed based on three databases of RNA interaction. Next, survival analysis was performed for hub genes in the co-expression network, and the high-efficiency biomarkers that could predict the prognosis of patients with LGG undergoing radiotherapy was identified.

RESULTS

We found that some modules in the co-expression network were related to the radiotherapy responses in patients with LGG. Based on the genes in those modules and the three databases, we constructed a ceRNA network for the regulation of radiotherapy responses in LGG. We identified the hub genes and found that the long non-coding RNA, DRAIC, is a potential molecular biomarker to predict the prognosis of radiotherapy in LGG.

Long-Term Exposure to Temozolomide Affects Locomotor Activity and Cartilage Structure of Elderly Experimental Rats

Chemotherapy with temozolomide (TMZ) is an essential part of anticancer therapy of various malignant tumours; however, its long-term effects on patients’ health and life quality need to be further investigated. Here, we studied the effects of TMZ and/or companion drug dexamethasone (DXM) on the locomotor activity and cartilage structure of elderly Wistar rats (n = 40). Long-term TMZ treatment selectively inhibited the horizontal, but not vertical locomotor activity of the rats (6.7-fold, p < 0.01) and resulted in delamination of the superficial epiphyseal cartilage of the femoral epiphysis of knee joints, a 2-fold decrease in mean thickness of epiphyseal cartilage (p < 0.001), and changes in the proliferative and maturation cartilage zones ratio. The simultaneous use of DXM attenuated TMZ-induced changes in cartilage thickness and integrity and compensated the decrease in horizontal locomotor activity of experimental animals. Nevertheless, combined TMZ/DXM treatment still significantly affected the structure of proximal tibial, but not distal femoral epiphysis of knee joints of the rats. These changes were accompanied by the increased content of total glycosaminoglycans (GAGs) and their partial re-localisation from chondrocytes into tissue matrix, as well as the decrease in sulfated GAGs content in both compartments. Taken together, the results demonstrate that long-term treatment with TMZ results in a significant decrease in locomotor activity of elderly Wistar rats and the reorganisation of their knee joint cartilage structure, while DXM treatment attenuates those effects. So, use of DXM or chondroprotective drugs might be beneficial to maintain quality of life for TMZ-treated cancer patients.

Temozolomide-induced aplastic anaemia: Case report and review of the literature

INTRODUCTION

Temozolomide (TMZ) is an oral alkylating agent principally indicated for neurological malignancies including glioblastoma (GBM) and astrocytoma. Most common side effects are mild to moderate, and include fatigue, nausea, vomiting, thrombocytopenia and neutropenia. Severe or prolonged myelosuppression, causing delayed treatment or discontinuation, is uncommon. Major haematological adverse effects such as myelodysplastic syndrome or aplastic anaemia (AA) have rarely been reported.

CASE REPORT

We report a 68-year old female with GBM treated at a tertiary hospital with short-course radiotherapy and concurrent temozolomide following craniotomy. On treatment completion she was transferred to our hospital for rehabilitation. She was thrombocytopenic on admission. Platelets continued falling with significant pancytopenia developing over the next two weeks. Blood parameters and a markedly hypocellular bone marrow confirmed the diagnosis of very severe AA, probably due to TMZ.

MANAGEMENT AND OUTCOME

Treatment consisted of repeated platelet transfusions, intravenous antibiotics, antiviral and antifungal prophylaxis, and G-CSF 300 mcg daily. Platelet and neutrophil counts had returned to normal at 38 days following the completion of TMZ treatment.

DISCUSSION

Whilst most cases of AA are idiopathic, a careful drug, occupational exposure and family history should be obtained, as acquired AA may result from viruses, chemical exposure, radiation and medications. Temozolomide-induced AA is well documented, though only 12 cases have been described in detail. Other potential causes were eliminated in our patient. Physicians should be aware of this rare and potentially fatal toxicity when prescribing. Frequent blood tests should be performed, during and following TMZ treatment, to enable early detection.

Aggressive prolactinomas: how to manage?

PURPOSE

Aggressive prolactinomas are defined as radiologically invasive tumors which cannot be cured by surgery, and that have an unusually rapid rate of tumor growth despite dopamine agonist treatment and surgery. In some cases, metastasis occurs, defining prolactin carcinoma which is the second most frequent pituitary carcinoma.

METHODS

A literature search was performed to review the available data on the treatment of aggressive pituitary prolactinomas or carcinomas.

RESULTS

When optimal standard therapies (high dose cabergoline, surgery and radiotherapy) failed, temozolomide, an alkylating drug, is currently the best option, allowing to control tumor growth in about 50% of treated prolactinomas and improving overall survival of these patients. However, long-term complete response occurs in a limited subgroup of tumors. Alternative drugs could be discussed in a subset of aggressive prolactinomas either before temozolomide (pasireotide, peptide receptor radionuclide therapy…) or after temozolomide failure.

CONCLUSION

Despite the significant improvement obtained with the use of temozolomide, a need for alternative drugs persists since a majority of these tumors are resistant or will recur during the follow-up. Patients suffering from such a rare condition should have access to clinical trials available for other types of rare cancers, such as tyrosine kinase inhibitors or immunotherapy.

Tunable Stability of Imidazotetrazines Leads to a Potent Compound for Glioblastoma

Even in the era of personalized medicine and immunotherapy, temozolomide (TMZ), a small molecule DNA alkylating agent, remains the standard-of-care for glioblastoma (GBM). TMZ has an unusual mode-of-action, spontaneously converting to its active component via hydrolysis in vivo. While TMZ has been FDA approved for two decades, it provides little benefit to patients whose tumors express the resistance enzyme MGMT and gives rise to systemic toxicity through myelosuppression. TMZ was first synthesized in 1984, but certain key derivatives have been inaccessible due to the chemical sensitivity of TMZ, precluding broad exploration of the link between imidazotetrazine structure and biological activity. Here, we sought to discern the relationship between the hydrolytic stability and anticancer activity of imidazotetrazines, with the objectives of identifying optimal timing for prodrug activation and developing suitable compounds with enhanced efficacy via increased blood-brain barrier penetrance. This work necessitated the development of new synthetic methods to provide access to previously unexplored functionality (such as aliphatic, ketone, halogen, and aryl groups) at the C8 position of imidazotetrazines. Through synthesis and evaluation of a suite of compounds with a range of aqueous stabilities (from 0.5 to 40 h), we derive a predictive model for imidazotetrazine hydrolytic stability based on the Hammett constant of the C8 substituent. Promising compounds were identified that possess activity against a panel of GBM cell lines, appropriate hydrolytic and metabolic stability, and brain-to-serum ratios dramatically elevated relative to TMZ, leading to lower hematological toxicity profiles and superior activity to TMZ in a mouse model of GBM. This work points a clear path forward for the development of novel and effective anticancer imidazotetrazines.

Early platelet variation during concomitant chemo-radiotherapy predicts adjuvant temozolomide-induced thrombocytopenia in newly diagnosed glioblastoma patients

PURPOSE

Temozolomide (TMZ) is known to induce thrombocytopenia but no early predictive test has yet been clearly established. The aim of the study was to retrospectively identify and validate a threshold of early platelet variation predicting TMZ-induced thrombocytopenia during the TMZ phase in patients treated according to the Stupp protocol for glioblastoma.

METHODS

A training set was used to analyze variations in platelet count occurring from the first week (W1) to week 6 (W6) during radiotherapy. Our aim was to identify the most relevant platelet decrease associated with TMZ-induced thrombocytopenia ≤ 100 G/L at day 28 during the TMZ phase. The performance of the threshold was confirmed in an independent validation set.

RESULTS

Overall, 147 patients were included, 85 and 62 in the training and validation sets, respectively. Twenty-seven patients (18%) experienced at least one TMZ-induced thrombocytopenia in the TMZ phase. A platelet decrease at W6 ≥ 35% (∆W6 ≥ 35%) was identified as the best predictive variation with an AUC of 0.83, a sensitivity of 65%, and a specificity of 96%. In the validation set, ∆W6 ≥ 35% platelet variation was identified as an independent marker of TMZ-induced thrombocytopenia during the TMZ phase (OR 15.23 (95% CI 3.5-107.5)) corresponding to sensitivity of 77% (66-87%), specificity of 73% (62-84%), a positive predictive value of 42% (29-54%), and a negative predictive value of 92% (86-99%).

CONCLUSION

Platelet decrease at W6 ≥ 35% during the RT-TMZ phase is an early and simple predictive marker of clinically relevant TMZ-induced thrombocytopenia during TMZ maintenance.

Acute lymphoblastic leukemia following temozolomide treatment in a patient with glioblastoma: A case report and review of the literature

Temozolomide (TMZ) is a second-generation oral alkylating agent that functions against a number of central nervous system neoplasms, and is generally used to treat high-grade gliomas, including anaplastic astrocytoma and glioblastoma multiforme. Therapy-related secondary myelodysplastic syndrome and acute myeloid leukemia have been reported in patients following prolonged exposure to TMZ. However, TMZ-related acute lymphoblastic leukemia (ALL) is extremely rare. The present study describes the case of an 11-year-old boy with a 3-day history of generalized tonic-clonic seizures and a contrast-enhanced lesion in the left temporooccipital region with focal cystic degeneration, as detected by magnetic resonance imaging. The patient underwent craniotomy and gross-total resection andpathological analysis confirmed the diagnosis of giant cell glioblastoma. Postoperatively, the patient received TMZ-based concurrent chemoradiation during radiotherapy, and developed B-cell ALL 6 months following TMZ treatment. A thorough literature search identified only six published cases of TMZ-related ALL. The chemotherapeutic efficacy of TMZ has been identified, however, its leukemogenic potential should be emphasized among practitioners and patients. Further studies are required to determine the specific pathogenic mechanism of TMZ-related ALL. Close hematological monitoring of patients following TMZ treatment is vital and a high index of suspicion is necessary.

Prolonged survival in secondary glioblastoma following local injection of targeted alpha therapy with 213Bi-substance P analogue

Background

Glioblastoma multiforme (GBM), the most common malignant brain tumor, mainly manifests as a primary de novo and less frequently as a secondary glial neoplasm. GBM has been demonstrated to overexpress the NK-1 receptor and substance P can be used as a ligand for targeted therapy. Alpha emitters, e.g. ²¹³Bi, that deposit their high energy within a short range allow the selective irradiation of tumor cells while sparing adjacent neuronal structures.

Material and methods

Among 50 glioma patients of different subtypes that have to date been treated with targeted alpha therapy at the Medical University Warsaw, we report here the data on nine patients with secondary GBM. Following surgery, chemo- and radiotherapy, recurrent GBM was treated by intracavitary injection of 1–6 doses of 0.9–2.3 GBq ²¹³Bi- DOTA-[Thi⁸,Met(O₂)¹¹]-substance P (²¹³Bi-DOTA-SP) in 2-month intervals. ⁶⁸Ga-DOTA-[Thi⁸,Met(O₂)¹¹]-substance P (⁶⁸Ga-DOTA-SP) was co-injected with the therapeutic doses to assess biodistribution using PET/CT. Therapeutic response was monitored with MRI.

Results

Treatment with activities ranging from 1.4 to 9.7 (median 5.8) GBq ²¹³Bi- DOTA-SP was well tolerated with only mild transient adverse reactions, mainly headaches due to a transient perfocal edema reaction. The median progression free survival and overall survival time following the initiation of alpha therapy was 5.8 and 16.4 months, respectively. The median overall survival time from the first diagnosis was 52.3 months. Two out of nine patients are still alive 39 and 51 months, respectively, after the initiation of the therapy.

Conclusions

Targeted alpha therapy of secondary GBM with ²¹³Bi-DOTA-SP is safe and well tolerated and may evolve as a promising novel therapeutic option for secondary GBM.

Targeted nanoparticle delivery of therapeutic antisense microRNAs presensitizes glioblastoma cells to lower effective doses of temozolomide in vitro and in a mouse model

Temozolomide (TMZ) chemotherapy for glioblastoma (GBM) is generally well tolerated at standard doses but it can cause side effects. GBMs overexpress microRNA-21 and microRNA-10b, two known oncomiRs that promote cancer development, progression and resistance to drug treatment. We hypothesized that systemic injection of antisense microRNAs (antagomiR-21 and antagomiR-10b) encapsulated in cRGD-tagged PEG-PLGA nanoparticles would result in high cellular delivery of intact functional antagomiRs, with consequent efficient therapeutic response and increased sensitivity of GBM cells to lower doses of TMZ. We synthesized both targeted and non-targeted nanoparticles, and characterized them for size, surface charge and encapsulation efficiency of antagomiRs. When using targeted nanoparticles in U87MG and Ln229 GBM cells, we showed higher uptake-associated improvement in sensitivity of these cells to lower concentrations of TMZ in medium. Co-inhibition of microRNA-21 and microRNA-10b reduced the number of viable cells and increased cell cycle arrest at G2/M phase upon TMZ treatment. We found a significant increase in expression of key target genes for microRNA-21 and microRNA-10b upon using targeted versus non-targeted nanoparticles. There was also significant reduction in tumor volume when using TMZ after pre-treatment with loaded nanoparticles in human GBM cell xenografts in mice. In vivo targeted nanoparticles plus different doses of TMZ showed a significant therapeutic response even at the lowest dose of TMZ, indicating that preloading cells with antagomiR-21 and antagomiR-10b increases cellular chemosensitivity towards lower TMZ doses. Future clinical applications of this combination therapy may result in improved GBM response by using lower doses of TMZ and reducing nonspecific treatment side effects.

Persistent bone marrow depression following short-term treatment with temozolomide

Temozolomide (TMZ) is, in combination with radiotherapy (RT), the treatment of choice for glioblastoma multiforme. Although generally well tolerated, haematological side effects are observed in approximately 1-10% of patients receiving TMZ. We report a case of a patient who developed severe bone marrow failure (BMF) after only 3 weeks of concomitant TMZ. The BMF was grave with no signs of improvement for 12 months, resulting in more than 100 transfusions of blood cells.

Haematological toxicity of Valproic acid compared to Levetiracetam in patients with glioblastoma multiforme undergoing concomitant radio-chemotherapy: a retrospective cohort study

Patients with glioblastoma multiforme (GBM) and symptomatic seizures are in need of a sufficient antiepileptic treatment. Haematological toxicity is a limiting side effect of both, first line radio-chemotherapy with temozolomide (TMZ) and co-medication with antiepileptic drugs. Valproic acid (VPA) and levetiracetam (LEV) are considered favourable agents in brain tumor patients with seizures, but are commonly reported to induce haematological side effects on their own. We hypothesized, that antiepileptic treatment with these agents has no increased impact on haematological side effects during radio-chemotherapy in the first line setting. We included 104 patients from two neuro-oncologic centres with GBM and standard radio-chemotherapy in a retrospective cohort study. Patients were divided according to their antiepileptic treatment with either VPA, LEV or without antiepileptic drug therapy (control group). Declines in haemoglobin levels and absolute blood cell counts for neutrophil granulocytes, lymphocytes and thrombocytes were analyzed twice during concomitant and once during adjuvant phase. A comparison between the examined groups was performed, using a linear mixed model. Neutrophil granulocytes, lymphocytes and thrombocytes significantly decreased over time in all three groups (all p < 0.012), but there was no significant difference between the compared groups. A significant decline in haemoglobin was observed in the LEV treated group (p = 0.044), but did not differ between the compared groups. As a novel finding, this study demonstrates that co-medication either with VPA or LEV in GBM patients undergoing first line radio-chemotherapy with TMZ has no additional impact on medium-term haematological toxicity.