Clinical and Genetic Factors Associated With Severe Hematological Toxicity in Glioblastoma Patients During Radiation Plus Temozolomide Treatment: A Prospective Study

Novel 9-Methylanthracene Derivatives as p53 Activators for the Treatment of Glioblastoma Multiforme

Glioblastoma multiforme, a highly aggressive and lethal brain tumor, is a substantial clinical challenge and a focus of increasing concern globally. Hematological toxicity and drug resistance of first-line drugs underscore the necessity for new anti-glioma drug development. Here, 43 anthracenyl skeleton compounds as p53 activator XI-011 analogs were designed, synthesized, and evaluated for their cytotoxic effects. Five compounds (13d, 13e, 14a, 14b, and 14n) exhibited good anti-glioma activity against U87 cells, with IC50 values lower than 2 μM. Notably, 13e showed the best anti-glioma activity, with an IC50 value up to 0.53 μM, providing a promising lead compound for new anti-glioma drug development. Mechanistic analyses showed that 13e suppressed the MDM4 protein expression, upregulated the p53 protein level, and induced cell cycle arrest at G2/M phase and apoptosis based on Western blot and flow cytometry assays.

Impact of sex on treatment-related adverse effects and prognosis in nasopharyngeal carcinoma

BACKGROUND

In nasopharyngeal cancer (NPC), women have a lower incidence and mortality rate than men. Whether sex influences the prognosis of NPC patients remains debatable. We retrospectively examined the influence of sex on treatment-related side effects and prognosis in NPC.

METHODS

Clinical data of 1,462 patients with NPC treated at the Southern Hospital of Southern Medical University from January 2004 to December 2015 were retrospectively examined. Statistical analysis was performed to assess differences in overall survival (OS), distant metastasis-free survival (DMFS), local recurrence-free survival(LRFS), and progression-free survival(PFS), as well as treatment-related adverse effects, including myelosuppression, gastrointestinal responses, and radiation pharyngitis and dermatitis, between men and women.

RESULTS

Women had better 5-year OS (81.5% vs. 87.1%, P = 0.032) and DMFS (76.2% vs. 83.9%, P = 0.004) than men. Analysis by age showed that the prognoses of premenopausal and menopausal women were better than those of men, whereas prognoses of postmenopausal women and men were not significantly different. Additionally, women had a better prognosis when stratified by treatment regimen. Furthermore, chemotherapy-related adverse effects were more severe in women than in men; however, the incidences of radiation laryngitis and dermatitis were not significantly different between the sexes. Logistic regression analysis revealed that the female sex was an independent risk factor for severe myelosuppression and gastrointestinal reactions.

CONCLUSIONS

Chemotherapy-related side effects are more severe but the overall prognosis is better in women with NPC than in men with NPC. Patients may benefit from a personalized treatment approach for NPC.

TRIAL REGISTRATION

This study was approved by the Medical Ethics Committee of Nanfang Hospital of the Southern Medical University (NFEC-201,710-K3).

Myelotoxicity of Temozolomide Treatment in Patients with Glioblastoma Is It Time for a More Mechanistic Approach?

Glioblastoma multiforme is the most common primary central nervous system tumor, with an incidence of 3 [...].

Patterns, predictors and prognostic relevance of high-grade hematotoxicity after temozolomide or temozolomide-lomustine in the CeTeG/NOA-09 trial

PURPOSE

In the randomized phase III trial CeTeG/NOA-09, temozolomide (TMZ)/lomustine (CCNU) combination therapy was superior to TMZ in newly diagnosed MGMT methylated glioblastoma, albeit reporting more frequent hematotoxicity. Here, we analyze high grade hematotoxicity and its prognostic relevance in the trial population.

METHODS

Descriptive and comparative analysis of hematotoxicity adverse events ≥ grade 3 (HAE) according to the Common Terminology of Clinical Adverse Events, version 4.0 was performed. The association of HAE with survival was assessed in a landmark analysis. Logistic regression analysis was performed to predict HAE during the concomitant phase of chemotherapy.

RESULTS

HAE occurred in 36.4% and 28.6% of patients under CCNU/TMZ and TMZ treatment, respectively. The median onset of the first HAE was during concomitant chemotherapy (i.e. first CCNU/TMZ course or daily TMZ therapy), and 42.9% of patients with HAE receiving further courses experienced repeat HAE. Median HAE duration was similar between treatment arms (CCNU/TMZ 11.5; TMZ 13 days). Chemotherapy was more often discontinued due to HAE in CCNU/TMZ than in TMZ (19.7 vs. 6.3%, p = 0.036). The occurrence of HAE was not associated with survival differences (p = 0.76). Regression analysis confirmed older age (OR 1.08) and female sex (OR 2.47), but not treatment arm, as predictors of HAE.

CONCLUSION

Older age and female sex are associated with higher incidence of HAE. Although occurrence of HAE was not associated with shorter survival, reliable prediction of patients at risk might be beneficial to allow optimal management of therapy and allocation of supportive measures.

TRIAL REGISTRATION

NCT01149109.

Keep a watchful eye on methionine adenosyltransferases, novel therapeutic opportunities for hepatobiliary and pancreatic tumours

Methionine adenosyltransferases (MATs) synthesize S-adenosylmethionine (SAM) from methionine, which provides methyl groups for DNA, RNA, protein, and lipid methylation. MATs play a critical role in cellular processes, including growth, proliferation, and differentiation, and have been implicated in tumour development and progression. The expression of MATs is altered in hepatobiliary and pancreatic (HBP) cancers, which serves as a rare biomarker for early diagnosis and prognosis prediction of HBP cancers. Independent of SAM depletion in cells, MATs are often dysregulated at the transcriptional, post-transcriptional, and post-translational levels. Dysregulation of MATs is involved in carcinogenesis, chemotherapy resistance, T cell exhaustion, activation of tumour-associated macrophages, cancer stemness, and activation of tumourigenic pathways. Targeting MATs both directly and indirectly is a potential therapeutic strategy. This review summarizes the dysregulations of MATs, their proposed mechanism, diagnostic and prognostic roles, and potential therapeutic effects in context of HBP cancers.

Prognostic significance of therapy-induced myelosuppression in newly diagnosed glioblastoma

BACKGROUND

Myelosuppression is the major toxicity encountered during temozolomide chemoradiotherapy for newly diagnosed glioblastoma.

METHODS

We assessed the association of myelosuppression (neutropenia, thrombocytopenia, anemia, and lymphopenia) during temozolomide chemoradiotherapy alone or in combination with experimental agents with progression-free survival (PFS) or overall survival (OS) in 2073 patients with newly diagnosed glioblastoma enrolled into five clinical trials: CENTRIC, CORE, EORTC 26082, AVAglio, and EORTC 26981. A landmark Cox model was used. For each primary association analysis, a significance level of 1.7% was used.

RESULTS

Lower neutrophil counts at baseline were associated with better PFS (P = .011) and OS (P < .001), independently of steroid intake. Females experienced uniformly more myelotoxicity than males. Lymphopenia during concomitant chemoradiotherapy was associated with OS (P = .009): low-grade (1-2) lymphopenia might be associated with superior OS (HR 0.78, 98.3% CI 0.58-1.06), whereas high-grade (3-4) lymphopenia might be associated with inferior OS (HR 1.08, 98.3% CI 0.75-1.54). There were no associations of altered hematological parameters during concomitant chemoradiotherapy with PFS. During maintenance chemoradiotherapy, no significant association was found between any parameter of myelosuppression and PFS or OS, although exploratory analysis at 5% significance level indicated that either mild-to-moderate (HR 0.76, 95% CI 0.62-0.93) or high-grade lymphopenia (HR 0.65, 95% CI 0.46-0.92) was associated with superior OS (P = .013), but not PFS.

CONCLUSIONS

The association of higher neutrophil counts at baseline with inferior PFS and OS requires further prospective evaluation. The link of therapy-induced lymphopenia to better outcome may guide the design for immunotherapy trials in newly diagnosed glioblastoma.

The Next Frontier in Health Disparities—A Closer Look at Exploring Sex Differences in Glioma Data and Omics Analysis, from Bench to Bedside and Back

Sex differences are increasingly being explored and reported in oncology, and glioma is no exception. As potentially meaningful sex differences are uncovered, existing gender-derived disparities mirror data generated in retrospective and prospective trials, real-world large-scale data sets, and bench work involving animals and cell lines. The resulting disparities at the data level are wide-ranging, potentially resulting in both adverse outcomes and failure to identify and exploit therapeutic benefits. We set out to analyze the literature on women’s data disparities in glioma by exploring the origins of data in this area to understand the representation of women in study samples and omics analyses. Given the current emphasis on inclusive study design and research, we wanted to explore if sex bias continues to exist in present-day data sets and how sex differences in data may impact conclusions derived from large-scale data sets, omics, biospecimen analysis, novel interventions, and standard of care management.

Pump proton inhibitors display anti-tumour potential in glioma

OBJECTIVES

Glioma is one of the most aggressive brain tumours with poor overall survival despite advanced technology in surgical resection, chemotherapy and radiation. Progression and recurrence are the hinge causes of low survival. Our aim is to explain the concrete mechanism in the proliferation and progression of tumours based on tumour microenvironment (TME). The main purpose is to illustrate the mechanism of proton pump inhibitors (PPIs) in affecting acidity, hypoxia, oxidative stress, inflammatory response and autophagy based on the TME to induce apoptosis and enhance the sensitivity of chemoradiotherapy.

FINDINGS

TME is the main medium for tumour growth and progression. Acidity, hypoxia, inflammatory response, autophagy, angiogenesis and so on are the main causes of tumour progress. PPIs, as a common clinical drug to inhibit gastric acid secretion, have the advantages of fast onset, long action time and small adverse reactions. Nowadays, several kinds of literature highlight the potential of PPIs in inhibiting tumour progression. However, long-term use of PPIs alone also has obvious side effects. Therefore, till now, how to apply PPIs to promote the effect of radio-chemotherapy and find the concrete dose and concentration of combined use are novel challenges.

CONCLUSIONS

PPIs display the potential in enhancing the sensitivity of chemoradiotherapy to defend against glioma based on TME. In the clinic, it is also necessary to explore specific concentrations and dosages in synthetic applications.

Brain radiotoxicity-related 15CAcBRT gene expression signature predicts survival prognosis of glioblastoma patients

BACKGROUND

Glioblastoma is the most common and devastating primary brain cancer. Radiotherapy is standard of care; however, it is associated with brain radiation toxicity (BRT). This study used a multi-omics approach to determine whether BRT-related genes (RGs) harbor survival prognostic value and whether their encoded proteins represent novel therapeutic targets for glioblastoma.

METHODS

RGs were identified through analysis of single-nucleotide variants associated with BRT (R-SNVs). Functional relationships between RGs were established using Protein-Protein Interaction networks. The influence of RGs and their functional groups on glioblastoma prognosis was evaluated using clinical samples from the Glioblastoma Bio-Discovery Portal database and validated using the Chinese Glioma Genome Atlas dataset. The identification of clusters of radiotoxic and putative pathogenic variants in proteins encoded by RGs was achieved by computational 3D structural analysis.

RESULTS

We identified the BRT-related 15CAcBRT molecular signature with prognostic value in glioblastoma, by analysis of the COMT and APOE protein functional groups. Its external validation confirmed clinical relevance independent of age, MGMT promoter methylation status, and IDH mutation status. Interestingly, the genes IL6, APOE, and MAOB documented significant gene expression levels alteration, useful for drug repositioning. Biological networks associated with 15CAcBRT signature involved pathways relevant to cancer and neurodegenerative diseases. Analysis of 3D clusters of radiotoxic and putative pathogenic variants in proteins coded by RGs unveiled potential novel therapeutic targets in neuro-oncology.

CONCLUSIONS

15CAcBRT is a BRT-related molecular signature with prognostic significance for glioblastoma patients and represents a hub for drug repositioning and development of novel therapies.

Tumor-activated carrier-free prodrug nanoparticles for targeted cancer Immunotherapy: Preclinical evidence for safe and effective drug delivery

As immunogenic cell death (ICD) inducers initiating antitumor immune responses, certain chemotherapeutic drugs have shown considerable potential to reverse the immunosuppressive tumor microenvironment (ITM) into immune-responsive tumors. The application of these drugs in nanomedicine provides a more enhanced therapeutic index by improving unfavorable pharmacokinetic (PK) profiles and inefficient tumor targeting. However, the clinical translation of conventional nanoparticles is restricted by fundamental problems, such as risks of immunogenicity and potential toxicity by carrier materials, premature drug leakage in off-target sites during circulation, low drug loading contents, and complex structure and synthetic processes that hinder quality control (QC) and scale-up industrial production. To address these limitations, tumor-activated carrier-free prodrug nanoparticles (PDNPs), constructed only by the self-assembly of prodrugs without any additional carrier materials, have been widely investigated with distinct advantages for safe and more effective drug delivery. In addition, combination immunotherapy based on PDNPs with other diverse modalities has efficiently reversed the ITM to immune-responsive tumors, potentiating the response to immune checkpoint blockade (ICB) therapy. In this review, the trends and advances in PDNPs are outlined, and each self-assembly mechanism is discussed. In addition, various combination immunotherapies based on PDNPs are reviewed. Finally, a physical tumor microenvironment remodeling strategy to maximize the potential of PDNPs, and key considerations for clinical translation are highlighted.

PrACTiC: A Predictive Algorithm for Chemoradiotherapy-Induced Cytopenia in Glioblastoma Patients

Background

Chemotherapy-induced cytopenia is the most frequent side effect of chemoradiotherapy in glioblastoma patients which may lead to reduced delivery of treatment. This study aims to develop a predictive model that is able to forecast the cytopenia induced by temozolomide (TMZ) during concomitant chemoradiotherapy.

Methods

Medical records of 128 patients with newly diagnosed glioblastoma were evaluated to extract the baseline complete blood test before and during the six weeks of chemoradiotherapy to create a dataset for the development of ML models. Using the constructed dataset, different ML algorithms were trained and tested.

Results

Our proposed algorithm achieved accuracies of 85.6%, 88.7%, and 89.3% in predicting thrombocytopenia, lymphopenia, and neutropenia, respectively.

Conclusions

The algorithm designed and developed in this study, called PrACTiC, showed promising results in the accurate prediction of thrombocytopenia, neutropenia, and lymphopenia induced by TMZ in glioblastoma patients. PrACTiC can provide valuable insight for physicians and help them to make the necessary treatment modifications and prevent the toxicities.

Temozolomide-induced myelotoxicity and single nucleotide polymorphisms in the MGMT gene in patients with adult diffuse glioma: a single-institutional pharmacogenetic study

PURPOSE

Nearly 10% of patients with adult diffuse glioma develop clinically significant myelotoxicity while on temozolomide (TMZ) leading to treatment interruptions. This study aimed to assess single nucleotide polymorphisms (SNPs) in the O⁶-methylguanine-DNA methyltransferase (MGMT) gene in adults with biopsy-proven diffuse glioma who develop TMZ-induced myelotoxicity and correlate their presence with severity and duration of such toxicity.

METHODS

This study assessed 33 adults treated with TMZ for diffuse glioma who developed ≥ grade 2 thrombocytopenia and/or ≥ grade 3 neutropenia. Genomic DNA was extracted from peripheral blood cells for MGMT SNP analysis after written informed consent. TMZ-induced severe myelotoxicity (≥ grade 3) was correlated with three specified SNPs commonly seen in the MGMT gene (L84F, I143V/K178R) using chi-square test or Fischer's exact test as appropriate.

RESULTS

Of the 33 adults, 24 (72.7%) experienced ≥ grade 3 thrombocytopenia and/or neutropenia, while 9 (27.3%) developed grade 2 thrombocytopenia only. The variant T allele of L84F was expressed in 28.7% (19/66) of analyzed alleles, which was substantially higher than previously reported for South Asian ancestry. The variant G allele of I143V/K178R was expressed in 9.3% (6/64) of analyzed alleles. Of which 3 patients showed statistically significant association with prolonged myelosuppression for > 2 months (p = 0.03). No significant correlation was established between the mentioned SNPs and severe myelotoxicity.

CONCLUSIONS

There is substantially higher frequency of variant T allele (L84F) in Indian patients than previously reported for South Asians. The presence of specific SNPs in the MGMT gene correlates with prolonged duration but not severity of TMZ-induced myelotoxicity.

Hematological adverse events in the management of glioblastoma

BACKGROUND

Hematological adverse events (HAEs) are common during treatment for glioblastoma (GBM), usually associated with temozolomide (TMZ). Their clinical value is uncertain, as few investigations have focused on outcomes for HAEs during GBM treatment.

METHODS

We combined data from two randomized clinical trials, RTOG 0525 and RTOG 0825, to analyze HAEs during treatment for GBM. We investigated differences between chemoradiation and adjuvant therapy, and by regimen received during adjuvant treatment.

RESULTS

1454 patients participated in these trials, of which 1154 (79.4%) developed HAEs. During chemoradiation, 44.4% of patients developed HAEs (54% involving more than one cell line), and were most commonly lymphopenia (50.6%), and thrombocytopenia (47.5%). During adjuvant treatment, 45% of patients presented HAEs (78.6% involving more than one cell line), and were more commonly leukopenia (62.7%), and thrombocytopenia (62.3%). Median overall survival (OS) and progression free survival (PFS) were longer in patients with HAEs (OS 19.4 months and PFS 9.9 months) compared to those with other or no adverse events (OS 14.1 months and PFS 5.9 months). There was no significant difference in survival between grade 1 and/or 2 versus grade 3 and/or 4 HAEs. History of HAEs during chemoradiation was a protective factor for presentation of HAEs during adjuvant therapy.

CONCLUSION

HAEs are common during GBM treatment, and often involve more than one cell line (more likely during adjuvant therapy). HAEs may be associated with prolonged OS and PFS, particularly during adjuvant therapy. HAEs during chemoradiation was a protective factor for HAEs during adjuvant therapy.

Germline polymorphisms in MGMT associated with temozolomide-related myelotoxicity risk in patients with glioblastoma treated on NRG Oncology/RTOG 0825

Background

We sought to identify clinical and genetic predictors of temozolomide-related myelotoxicity among patients receiving therapy for glioblastoma.

Methods

Patients (n = 591) receiving therapy on NRG Oncology/RTOG 0825 were included in the analysis. Cases were patients with severe myelotoxicity (grade 3 and higher leukopenia, neutropenia, and/or thrombocytopenia); controls were patients without such toxicity. A risk-prediction model was built and cross-validated by logistic regression using only clinical variables and extended using polymorphisms associated with myelotoxicity.

Results

23% of patients developed myelotoxicity (n = 134). This toxicity was first reported during the concurrent phase of therapy for 56 patients; 30 stopped treatment due to toxicity. Among those who continued therapy (n = 26), 11 experienced myelotoxicity again. The final multivariable clinical factor model included treatment arm, gender, and anticonvulsant status and had low prediction accuracy (area under the curve [AUC] = 0.672). The final extended risk prediction model including four polymorphisms in MGMT had better prediction (AUC = 0.827). Receiving combination chemotherapy (OR, 1.82; 95% CI, 1.02-3.27) and being female (OR, 4.45; 95% CI, 2.45-8.08) significantly increased myelotoxicity risk. For each additional minor allele in the polymorphisms, the risk increased by 64% (OR, 1.64; 95% CI, 1.43-1.89).

Conclusions

Myelotoxicity during concurrent chemoradiation with temozolomide is an uncommon but serious event, often leading to treatment cessation. Successful prediction of toxicity may lead to more cost-effective individualized monitoring of at-risk subjects. The addition of genetic factors greatly enhanced our ability to predict toxicity among a group of similarly treated glioblastoma patients.

Preoperative Thrombocytosis is Not Associated with Overall Survival in 309 Glioblastoma Patients

BACKGROUND

 In recent years, a correlation of thrombocytosis and a worse prognosis was shown for many solid cancers, including glioblastoma multiforme (GBM).

METHODS

 A retrospective review was performed for all patients with a histologically proven and first-diagnosed GBM between 2005 and 2015 in our department. Clinical and paraclinical parameters were acquired from patient documentation and structured for subsequent data analysis. The association of potential risk factors with overall survival was assessed using the Kaplan-Meier survival analysis and Cox regression.

RESULTS

 The present study includes 309 patients first diagnosed with primary GBM. Our analyses validate well-known risk factors of a decreased overall survival such as higher patient age, a larger preoperative tumor volume, Karnofsky performance status, extent of resection, tumor localization, and adjuvant treatment. However, no correlation was observed between a preoperative thrombocytosis, the mean platelet volume, leucocyte count, activated partial thromboplastin time (apTT), fibrinogen level, and acetylsalicylic acid 100 co-medication. Patients with preoperative hemoglobin below 7.5 mmol/L had decreased overall survival.

CONCLUSION

 The present study, enrolling the largest numbers of patients assessing this topic to date, did not find any association between a preoperative thrombocytosis and overall survival in 309 patients with GBM.

Overcoming delivery barriers in immunotherapy for glioblastoma

Glioblastoma is one of the deadliest forms of primary adult tumors, with median survival of 14.6 months post-diagnosis despite aggressive standard of care treatment. This grim prognosis for glioblastoma patients has changed little in the past two decades, necessitating novel treatment modalities. One potential treatment modality is cancer immunotherapy, which has shown remarkable progress in slowing disease progression or even potentially curing certain solid tumors. However, the transport barriers posed by the blood-brain barrier and the immune privileged status of the central nervous system pose drug delivery obstacles that are unique to brain tumors. In this review, we provide an overview of the various physiological, immunological, and drug delivery barriers that must be overcome for effective glioblastoma treatment. We discuss chemical modification strategies to enable nanomedicines to bypass the blood-brain barrier and reach intracranial tumors. Finally, we highlight recent advances in biomaterial-based strategies for cancer immunotherapy that can be adapted to glioblastoma treatment.

Gender and sex disparity in cancer trials

The study population within phase III clinical trials leading to approval of new cancer agents should ideally more closely mirror the population who will ultimately receive these agents. Although the number of females participating in clinical trials has increased over the past several decades, females are still under-represented in preclinical studies, in early phase clinical trials and even in some later phase cancer clinical trials. In the USA, this is particularly true for women from minority populations and elderly women. In this review, we review gender and sex disparities in cancer trials, the reasons for these disparities, the barriers to clinical trial enrolment and ways to improve diversity in cancer clinical trials.

Sex-Specific Differences in Glioblastoma

Sex differences have been well identified in many brain tumors. Even though glioblastoma (GBM) is the most common primary malignant brain tumor in adults and has the worst outcome, well-established differences between men and women are limited to incidence and outcome. Little is known about sex differences in GBM at the disease phenotype and genetical/molecular level. This review focuses on a deep understanding of the pathophysiology of GBM, including hormones, metabolic pathways, the immune system, and molecular changes, along with differences between men and women and how these dimorphisms affect disease outcome. The information analyzed in this review shows a greater incidence and worse outcome in male patients with GBM compared with female patients. We highlight the protective role of estrogen and the upregulation of androgen receptors and testosterone having detrimental effects on GBM. Moreover, hormones and the immune system work in synergy to directly affect the GBM microenvironment. Genetic and molecular differences have also recently been identified. Specific genes and molecular pathways, either upregulated or downregulated depending on sex, could potentially directly dictate GBM outcome differences. It appears that sexual dimorphism in GBM affects patient outcome and requires an individualized approach to management considering the sex of the patient, especially in relation to differences at the molecular level.

Adjuvant chemotherapy after severe myelotoxicity during chemoradiation phase in malignant gliomas. Is it feasibile? Results from AINO study (Italian Association for Neuro-Oncology)

BACKGROUND

Malignant gliomas (MG) are aggressive brain tumours in adults. The standard of care is concurrent radiation plus temozolomide (TMZ) [chemo-radiotherapy (CRT)] followed by TMZ maintenance up to 6 months. TMZ is considered to have a low toxicity profile, but several studies reported occurrence of severe myelosuppression, especially during the concomitant phase. Toxicity may be prolonged, thus treatment should be discontinued.

PURPOSE

To evaluate the risk of recurrente myelotoxicity during adjuvant chemotherapy (CT) in patients who recovered from severe myelotoxicity during CRT.

METHODS

We retrospectively collected data on patients with MG who developed and recovered from severe myelotoxicity during CRT from eight Italian neuro-oncology centers.

RESULTS

We included 87 patients. Histology was Glioblastoma (GBM) in 78 patients (89.7%); 60% of patients were female. After myelotoxicity recovery, 54 (62%) received treatment. The majority of them (82%, n = 44) received adjuvant TMZ and 18% (n = 10) others treatments. Out of 44 patients who received adjuvant TMZ, 34% experienced the re-occurrence of grade 3-4 myelotoxicity which required permanent CT discontinuation in 6 (13%) cases. Patients who received TMZ or other treatments had longer overall (OS) (adjusted HR 0.46, p = 0.008) and progression free survival (PFS) (adjusted HR 0.57, p = 0.034) than those who remained untreated.

CONCLUSION

Our study suggests that after severe myelotoxicity the majority of patients received treatment, particularly with TMZ. Only a fraction of patients experienced toxicity recurrence, suggesting that TMZ is well tolerated and had an impact on PFS and OS.

Sex-specific aspects of epidemiology, molecular genetics and outcome: primary brain tumours

Recent years have seen a great interest in sex-specific aspects of many diseases, including cancer, in part because of the assumption that females have often not been adequately represented in early drug development and determination of safety, tolerability and efficacy in clinical trials. Brain tumours represent a highly heterogeneous group of neoplastic diseases with strong variation of incidence by age, but partly also by sex. Most gliomas are more common in men whereas meningiomas, the most common primary intracranial tumours, are more common in females. Potential sex-specific genetic risk factors and specific sex biology have been reported in a tumour-specific manner. Several small studies have indicated differences in tolerability and safety of, as well as benefit from, treatment by sex, but no conclusive data have been generated. Exploring sex-specific aspects of neuro-oncology should be studied more systematically and in more depth in order to uncover the biological reasons for known sex differences in this disease.

Immunotherapy for Glioblastoma: Current State, Challenges, and Future Perspectives

Glioblastoma is the most lethal intracranial primary malignancy by no optimal treatment option. Cancer immunotherapy has achieved remarkable survival benefits against various advanced tumors, such as melanoma and non-small-cell lung cancer, thus triggering great interest as a new therapeutic strategy for glioblastoma. Moreover, the central nervous system has been rediscovered recently as a region for active immunosurveillance. There are vibrant investigations for successful glioblastoma immunotherapy despite the fact that initial clinical trial results are somewhat disappointing with unique challenges including T-cell dysfunction in the patients. This review will explore the potential of current immunotherapy modalities for glioblastoma treatment, especially focusing on major immune checkpoint inhibitors and the future strategies with novel targets and combo therapies. Immune-related adverse events and clinical challenges in glioblastoma immunotherapy are also summarized. Glioblastoma provides persistent difficulties for immunotherapy with a complex state of patients’ immune dysfunction and a variety of constraints in drug delivery to the central nervous system. However, rational design of combinational regimens and new focuses on myeloid cells and novel targets to circumvent current limitations hold promise to advent truly viable immunotherapy for glioblastoma.

Supramolecular prodrug hydrogelator as an immune booster for checkpoint blocker-based immunotherapy

Immune checkpoint blockers (ICBs) have shown great promise at harnessing immune system to combat cancer. However, only a fraction of patients can directly benefit from the anti-programmed cell death protein 1 (aPD1) therapy, and the treatment often leads to immune-related adverse effects. In this context, we developed a prodrug hydrogelator for local delivery of ICBs to boost the host's immune system against tumor. We found that this carrier-free therapeutic system can serve as a reservoir for extended tumoral release of camptothecin and aPD1 antibody, resulting in an immune-stimulating tumor microenvironment for boosted PD-1 blockade immune response. Our in vivo results revealed that this combination chemoimmunotherapy elicits robust and durable systemic anticancer immunity, inducing tumor regression and inhibiting tumor recurrence and metastasis. This work sheds important light into the use of small-molecule prodrugs as both chemotherapeutic and carrier to awaken and enhance antitumor immune system for improved ICBs therapy.

Prospects of biological and synthetic pharmacotherapies for glioblastoma

Introduction: The field of neuro-oncology has experienced significant advances in recent years. More is known now about the molecular and genetic characteristics of glioma than ever before. This knowledge leads to the understanding of glioma biology and pathogenesis, guiding the development of targeted therapeutics and clinical trials. The goal of this review is to describe the state of basic, translational, and clinical research as it pertains to biological and synthetic pharmacotherapy for gliomas.Areas covered: Challenges remain in designing accurate preclinical models and identifying patients that are likely to respond to a particular targeted therapy. Preclinical models for therapeutic assessment are critical to identify the most promising treatment approaches.Expert opinion: Despite promising new therapeutics, there have been no significant breakthroughs in glioma treatment and patient outcomes. Thus, there is an urgent need to better understand the mechanisms of treatment resistance and to design effective clinical trials.

Accumulation of DNA methylation alterations in paediatric glioma stem cells following fractionated dose irradiation

BACKGROUND

Radiation is an important therapeutic tool. However, radiotherapy has the potential to promote co-evolution of genetic and epigenetic changes that can drive tumour heterogeneity, formation of radioresistant cells and tumour relapse. There is a clinical need for a better understanding of DNA methylation alterations that may follow radiotherapy to be able to prevent the development of radiation-resistant cells.

METHODS

We examined radiation-induced changes in DNA methylation profiles of paediatric glioma stem cells (GSCs) in vitro. Five GSC cultures were irradiated in vitro with repeated doses of 2 or 4 Gy. Radiation was given in 3 or 15 fractions. DNA methylation profiling using Illumina DNA methylation arrays was performed at 14 days post-radiation. The cellular characteristics were studied in parallel.

RESULTS

Few fractions of radiation did not result in significant accumulation of DNA methylation alterations. However, extended dose fractionations changed DNA methylation profiles and induced thousands of differentially methylated positions, specifically in enhancer regions, sites involved in alternative splicing and in repetitive regions. Radiation induced dose-dependent morphological and proliferative alterations of the cells as a consequence of the radiation exposure.

CONCLUSIONS

DNA methylation alterations of sites with regulatory functions in proliferation and differentiation were identified, which may reflect cellular response to radiation stress through epigenetic reprogramming and differentiation cues.

Deleterious impact of a generic temozolomide formulation compared with brand-name product on the kinetic of platelet concentration and survival in newly diagnosed glioblastoma

Chemo-induced thrombocytopenia is a limiting toxicity among patients receiving temozolomide (TMZ) as first-line treatment for glioblastoma. We aimed to compare early platelet concentration kinetics, hematological safety profile, and impact on survival following the initiation of either the brand-name or a generic TMZ formulation. A retrospective trial was conducted in patients suffering from newly diagnosed glioblastoma. Patients were treated with TMZ at 75 mg/m² per day during six weeks, concomitantly with radiotherapy. Platelet concentration was collected each week. Primary endpoint was to perform a linear mixed-effect model of platelet concentration kinetic over weeks. A total of 147 patients were included as follows: 96 received the brand-name TMZ, and 51 received a generic TMZ formulation. Exposition to the generic was a significant variable that negatively influenced the platelet kinetics in the radiotherapy and concomitant TMZ phase, P = 0.02. Grade ≥3 chemo-induced thrombocytopenia was more frequent in the generic group: 19.6% [95% CI 8.7-30.5%] vs 3.1% [0-6.6%], P = 0.001. Exposition to the generic formulation of TMZ led to increase early treatment discontinuation due to TMZ-induced thrombocytopenia and was a worsening independent prognostic factor on overall survival: adjusted HR 1.83 [1.21-2.8], P = 0.031. These data suggest that exposition to a generic formulation of TMZ vs the brand-name product is associated with higher early platelet decrease leading to clinically relevant impacts on treatment schedule in glioblastoma. Further prospective trials are needed to confirm these results.

Nanocarrier-based drug combination therapy for glioblastoma

The current achievements in treating glioblastoma (GBM) patients are not sufficient because many challenges exist, such as tumor heterogeneity, the blood brain barrier, glioma stem cells, drug efflux pumps and DNA damage repair mechanisms. Drug combination therapies have shown increasing benefits against those challenges. With the help of nanocarriers, enhancement of the efficacy and safety could be gained using synergistic combinations of different therapeutic agents. In this review, we will discuss the major issues for GBM treatment, the rationales of drug combinations with or without nanocarriers and the principle of enhanced permeability and retention effect involved in nanomedicine-based tumor targeting and promising nanodiagnostics or -therapeutics. We will also summarize the recent progress and discuss the clinical perspectives of nanocarrier-based combination therapies. The goal of this article was to provide better understanding and key considerations to develop new nanomedicine combinations and nanotheranostics options to fight against GBM.

Development of cancer immunotherapy based on PD-1/PD-L1 pathway blockade

Programmed death receptor 1 (PD-1)/programmed death ligand 1 (PD-L1) blockade therapy has achieved considerable success in various tumours. However, only a fraction of patients benefit from its clinical application, and some patients might be suffer from tumour resistance against PD-1/PD-L1 blockade therapy after the original response. In this review, we summarized the main reasons that caused the low response rate of PD-/PD-L1 blockade therapy: firstly, the off-target of PD-1/PD-L1 blocking agents, which is also the main factor of the side effect of autoimmune disorders; secondly, the insufficient infiltration of T cells in a tumour microenvironment; thirdly, the low immunogenicity of tumor cells; fourth, other immunosuppressive components impairing the therapeutic efficacy of the immunotherapy based on the PD-/PD-L1 blockade, and introducing some updated the delivery system of PD-1/PD-L1 blocking agents and the combination therapy based on PD-1/PD-L1 inhibitors and other therapeutics that can complement and promote each other to achieve improved immune response.

Good tolerability of maintenance temozolomide in glioblastoma patients after severe hematological toxicity during concomitant radiotherapy and temozolomide treatment: report of two cases

Glioblastoma is the most common and aggressive primitive brain tumor in adults. Temozolomide (TMZ) administered daily with radiation therapy, followed by adjuvant TMZ has become the standard treatment. Although TMZ treatment has been considered to have a low toxicity profile, studies have noted the development of a severe myelosuppression, especially during the concomitant treatment; this toxicity may in some cases be prolonged and consequently treatment must be definitively discontinued. We analyzed two cases treated at our oncological center who developed severe and prolonged hematological toxicity during concomitant chemoradiotherapy treatment with TMZ. Hypothesizing that radiation therapy and daily TMZ could be the major causes of severe hematological toxicity during the concomitant phase, we decided to treat both patients with maintenance TMZ at the time of recovery of hematological values. Patients showed good tolerability without important myelosuppression. In conclusion, we suggest that glioblastoma patients with severe myelotoxicity during daily TMZ and radiation therapy be treated with maintenance TMZ at the time of blood value recovery.

Clinical correlates of severe thrombocytopenia from temozolomide in glioblastoma patients

BACKGROUND/AIM

This study was conducted retrospectively to evaluate rates of thrombocytopenia and their clinical impact during chemo-radiotherapy for glioblastomas and to elucidate associated clinical factors.

METHODS

A total of 64 patients who received temozolomide chemotherapy at our institution was included; 35 patients received full-dose chemo-radiotherapy as per the STUPP protocol (Group A), and 9 patients received abbreviated radiotherapy with concurrent chemotherapy (Group B). Twenty patients received temozolomide alone with an intended 12 cycles of therapy for first relapse at least 6 months after completion of adjuvant chemotherapy (Group C).

RESULTS

In Group A, 27 of 35 (77%) patients completed the chemo-radiotherapy phase; 14% had grade 3-4 thrombocytopenia leading to discontinuation. Of 27 patients, 16 (59%) completed adjuvant chemotherapy. There were no grade 3-4 thrombocytopenias, but 4% discontinued due to grade 2 thrombocytopenias. In Group B, four of nine (45%) patients completed the chemo-radiotherapy phase; 11% had grade 3-4 thrombocytopenias and discontinued treatment. Three of four (75%) patients completed adjuvant chemotherapy. Of these, 75% had grade 3-4 thrombocytopenias, but none discontinued. Finally, in Group C, 8 of 20 (40%) patients completed, with 10% discontinuing due to thrombocytopenias and the rest due to disease progression. In exploratory analyses, being female increased the risk of myelosuppresion, and there was a trend noticed in patients having a higher body surface area.

CONCLUSION

Our toxicity data were within range of the literature. We identified the group of patients that have increased thrombocytopenia risk. Larger pooled retrospective series and prospective studies are required.

High-Density Lipoprotein-Mimicking Nanodiscs for Chemo-immunotherapy against Glioblastoma Multiforme

Glioblastoma multiforme (GBM) is an aggressive primary brain tumor, for which there is no cure. Treatment effectiveness for GBM has been limited due to tumor heterogeneity, an immunosuppressive tumor microenvironment (TME), and the presence of the blood-brain barrier, which hampers the transport of chemotherapeutic compounds to the central nervous system (CNS). High-density lipoprotein (HDL)-mimicking nanodiscs hold considerable promise to achieve delivery of bioactive compounds into tumors. Herein, we tested the ability of synthetic HDL nanodiscs to deliver chemotherapeutic agents to the GBM microenvironment and elicit tumor regression. To this end, we developed chemo-immunotherapy delivery vehicles based on sHDL nanodiscs loaded with CpG, a Toll-like receptor 9 (TLR9) agonist, together with docetaxel (DTX), a chemotherapeutic agent, for targeting GBM. Our data show that delivery of DTX-sHDL-CpG nanodiscs into the tumor mass elicited tumor regression and antitumor CD8+ T cell responses in the brain TME. We did not observe any overt off-target side effects. Furthermore, the combination of DTX-sHDL-CpG treatment with radiation (IR), which is the standard of care for GBM, resulted in tumor regression and long-term survival in 80% of GBM-bearing animals. Mice remained tumor-free upon tumor cell rechallenge in the contralateral hemisphere, indicating the development of anti-GBM immunological memory. Collectively, these data indicate that sHDL nanodiscs constitute an effective drug delivery platform for the treatment of GBM, resulting in tumor regression, long-term survival, and immunological memory when used in combination with IR. The proposed delivery platform has significant potential for clinical translation.

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.

Anti-PD-1 antitumor immunity is enhanced by local and abrogated by systemic chemotherapy in GBM

The immunosuppressive effects of chemotherapy present a challenge for designing effective cancer immunotherapy strategies. We hypothesized that although systemic chemotherapy (SC) exhibits negative immunologic effects, local chemotherapy (LC) can potentiate an antitumor immune response. We show that LC combined with anti-programmed cell death protein 1 (PD-1) facilitates an antitumor immune response and improves survival (P < 0.001) in glioblastoma. LC-treated mice had increased infiltration of tumor-associated dendritic cells and clonal expansion of antigen-specific T effector cells. In comparison, SC resulted in systemic and intratumoral lymphodepletion, with decreased immune memory in long-term survivors. Furthermore, adoptive transfer of CD8⁺ cells from LC-treated mice partially rescued SC-treated mice after tumor rechallenge. Last, the timing of chemo- and immunotherapy had differential effects on anti-PD-1 efficacy. This study suggests that both mode of delivery and timing have distinct effects on the efficacy of anti-PD-1. The results of this work could help guide the selection and scheduling of combination treatment for patients with glioblastoma and other tumor types.

Checkpoints to the Brain: Directing Myeloid Cell Migration to the Central Nervous System

Myeloid cells are a unique subset of leukocytes with a diverse array of functions within the central nervous system during health and disease. Advances in understanding of the unique properties of these cells have inspired interest in their use as delivery vehicles for therapeutic genes, proteins, and drugs, or as "assistants" in the clean-up of aggregated proteins and other molecules when existing drainage systems are no longer adequate. The trafficking of myeloid cells from the periphery to the central nervous system is subject to complex cellular and molecular controls with several 'checkpoints' from the blood to their destination in the brain parenchyma. As important components of the neurovascular unit, the functional state changes associated with lineage heterogeneity of myeloid cells are increasingly recognized as important for disease progression. In this review, we discuss some of the cellular elements associated with formation and function of the neurovascular unit, and present an update on the impact of myeloid cells on central nervous system (CNS) diseases in the laboratory and the clinic. We then discuss emerging strategies for harnessing the potential of site-directed myeloid cell homing to the CNS, and identify promising avenues for future research, with particular emphasis on the importance of untangling the functional heterogeneity within existing myeloid subsets.

Can dosimetric parameters predict acute hematologic toxicity in rectal cancer patients treated with intensity-modulated pelvic radiotherapy?

Background

To identify dosimetric parameters associated with acute hematologic toxicity (HT) in rectal cancer patients undergoing concurrent chemotherapy and intensity-modulated pelvic radiotherapy.

Methods

Ninety-three rectal cancer patients receiving concurrent capecitabine and pelvic intensity-modulated radiation therapy (IMRT) were analyzed. Pelvic bone marrow (PBM) was contoured for each patient and divided into three subsites: lumbosacral spine (LSS), ilium, and lower pelvis (LP). The volume of each site receiving 5–40 Gy (V 5, V10, V15, V20, V30, and V40, respectively) as well as patient baseline clinical characteristics was calculated. The endpoint for hematologic toxicity was grade ≥ 2 (HT2+) leukopenia, neutropenia, anemia or thrombocytopenia. Logistic regression was used to analyze correlation between dosimetric parameters and grade ≥ 2 hematologic toxicity.

Results

Twenty-four in ninety-three patients experienced grade ≥ 2 hematologic toxicity. Only the dosimetric parameter V40 of lumbosacral spine was correlated with grade ≥ 2 hematologic toxicity. Increased pelvic lumbosacral spine V40 (LSS-V40) was associated with an increased grade ≥ 2 hematologic toxicity (p = 0.041). Patients with LSS-V40 ≥ 60 % had higher rates of grade ≥ 2 hematologic toxicity than did patients with lumbosacral spine V40 < 60 % (38.3 %, 18/47 vs.13 %, 6/46, p =0.005). On univariate and multivariate logistic regression analysis, lumbosacral spine V40 and gender was also the variable associated with grade ≥ 2 hematologic toxicity. Female patients were observed more likely to have grade ≥ 2 hematologic toxicity than male ones (46.9 %, 15/32 vs 14.8 %, 9/61, p =0.001).

Conclusions

Lumbosacral spine -V40 was associated with clinically significant grade ≥ 2 hematologic toxicity. Keeping the lumbosacral spine -V40 < 60 % was associated with a 13 % risk of grade ≥ 2 hematologic toxicity in rectal cancer patients undergoing concurrent chemoradiotherapy.