Ethical considerations of neuro-oncology trial design in the era of precision medicine

Nanoparticle-Based Combinational Strategies for Overcoming the Blood-Brain Barrier and Blood-Tumor Barrier

The blood-brain barrier (BBB) and blood-tumor barrier (BTB) pose substantial challenges to efficacious drug delivery for glioblastoma multiforme (GBM), a primary brain tumor with poor prognosis. Nanoparticle-based combinational strategies have emerged as promising modalities to overcome these barriers and enhance drug penetration into the brain parenchyma. This review discusses various nanoparticle-based combinatorial approaches that combine nanoparticles with cell-based drug delivery, viral drug delivery, focused ultrasound, magnetic field, and intranasal drug delivery to enhance drug permeability across the BBB and BTB. Cell-based drug delivery involves using engineered cells as carriers for nanoparticles, taking advantage of their intrinsic migratory and homing capabilities to facilitate the transport of therapeutic payloads across BBB and BTB. Viral drug delivery uses engineered viral vectors to deliver therapeutic genes or payloads to specific cells within the GBM microenvironment. Focused ultrasound, coupled with microbubbles or nanoparticles, can temporarily disrupt the BBB to increase drug permeability. Magnetic field-guided drug delivery exploits magnetic nanoparticles to facilitate targeted drug delivery under an external magnetic field. Intranasal drug delivery offers a minimally invasive avenue to bypass the BBB and deliver therapeutic agents directly to the brain via olfactory and trigeminal pathways. By combining these strategies, synergistic effects can enhance drug delivery efficiency, improve therapeutic efficacy, and reduce off-target effects. Future research should focus on optimizing nanoparticle design, exploring new combination strategies, and advancing preclinical and clinical investigations to promote the translation of nanoparticle-based combination therapies for GBM.

Patients' and professionals' views related to ethical issues in precision medicine: a mixed research synthesis

BACKGROUND

Precision medicine development is driven by the possibilities of next generation sequencing, information technology and artificial intelligence and thus, raises a number of ethical questions. Empirical studies have investigated such issues from the perspectives of health care professionals, researchers and patients. We synthesize the results from these studies in this review.

METHODS

We used a systematic strategy to search, screen and assess the literature for eligibility related to our research question. The initial search for empirical studies in five data bases provided 665 different records and we selected 92 of these publications for inclusion in this review. Data were extracted in a spreadsheet and categorized into different topics representing the views on ethical issues in precision medicine.

RESULTS

Many patients and professionals expect high benefits from precision medicine and have a positive attitude towards it. However, patients and professionals also perceive some risks. Commonly perceived risks include: lack of evidence for accuracy of tests and efficacy of treatments; limited knowledge of patients, which makes informed consent more difficult; possible unavailability of access to precision medicine for underprivileged people and ethnic minorities; misuse of data by insurance companies and employers, potential of racial stigmatization due to genetic information; unwanted communication of incidental findings; changes in doctor-patient-relationship through focusing on data; and the problem that patients could feel under pressure to optimize their health.

CONCLUSIONS

National legislation and guidelines already minimize many risks associated with precision medicine. However, from our perspective some problems require more attention. Should hopes for precision medicine's benefits be fulfilled, then the ethical principle of justice would require an unlimited access to precision medicine for all people. The potential for autonomous patients' decisions must be greatly enhanced by improvements in patient education. Harm from test results must be avoided in any case by the highest possible data security level and communication guidelines. Changes in the doctor-patient relationship and the impact of precision medicine on the quality of life should be further investigated. Additionally, the cost-effectiveness of precision medicine should be further examined, in order to avoid malinvestment.

Pharmacogenomics Implementation and Hurdles to Overcome; In the Context of a Developing Country

Having multiple dimensions, uncertainties and several stakeholders, the costly pharmacogenomics (PGx) is associated with dynamic implementation complexities. Identification of these challenges is critical to harness its full potential, especially in developing countries with fragile healthcare systems and scarce resources. This is the first study aimed to identify most salient challenges related to PGx implementation, with respect to the experiences of early-adopters and local experts' prospects, in the context of a developing country in the Middle East. To perform a comprehensive reconnaissance on PGx adoption challenges a scoping literature review was conducted based on national drug policy components: efficacy/safety, access, affordability and rational use of medicine (RUM). Strategic option development and analysis workshop method with cognitive mapping as the technique was used to evaluate challenges in the context of Iran. The cognitive maps were face-validated and analyzed via Decision Explorer XML. The findings indicated a complex network of issues relative to PGx adoption, categorized in national drug policy indicators. In the rational use of medicine category, ethics, education, bench -to- bedside strategies, guidelines, compliance, and health system issues were found. Clinical trial issues, test's utility, and biomarker validation were identified in the efficacy group. Affordability included pricing, reimbursement, and value assessment issues. Finally, access category included regulation, availability, and stakeholder management challenges. The current study identified the most significant challenges ahead of clinical implementation of PGx in a developing country. This could be the basis of a policy-note development in future work, which may consolidate vital communication among stakeholders and accelerate the efficient implementation in developing new-comer countries.

Single-Cell Analysis of Circulating Tumor Cells: How Far Have We Come in the -Omics Era?

Tumor cells detach from the primary tumor or metastatic sites and enter the peripheral blood, often causing metastasis. These cells, named Circulating Tumor Cells (CTCs), display the same spatial and temporal heterogeneity as the primary tumor. Since CTCs are involved in tumor progression, they represent a privileged window to disclose mechanisms of metastases, while -omic analyses at the single-cell level allow dissection of the complex relationships between the tumor subpopulations and the surrounding normal tissue. However, in addition to reporting the proof of concept that we can query CTCs to reveal tumor evolution throughout the continuum of treatment for early detection of resistance to therapy, the scientific literature has also been highlighting the disadvantages of CTCs, which hampers a routine use of this approach in clinical practice. To date, an increasing number of CTC technologies, as well as -omics methods, have been employed, mostly lacking strong comparative analyses. The rarity of CTCs also represents a major challenge, because there is no consensus regarding the minimal criteria necessary and sufficient to define an event as CTC; moreover, we cannot often compare data from of one study with that of another. Finally, the availability of an individual tumor profile undermines the traditional histology-based treatment. Applying molecular data for patient benefit implies a collective effort by biologists, bioengineers, and clinicians, to create tools to interpret molecular data and manage precision medicine in every single patient. Herein, we focus on the most recent findings in CTC −omics to learn how far we have come.

Development of the CNS TAP tool for the selection of precision medicine therapies in neuro-oncology

The number of targeted therapies utilized in precision medicine are rapidly increasing. Neuro-oncology offers a unique challenge due to the varying blood brain barrier (BBB) penetration of each agent. Neuro-oncologists face a difficult task weighing the growing number of potential targeted therapies and their likelihood of BBB penetration. We developed the CNS TAP Working Group and performed an extensive literature review for the evidence-based creation of the CNS TAP tool, which was retrospectively validated by analyzing brain tumor patients who underwent therapy targeted based on genomic results from an academic sequencing study (MiOncoseq, n = 17) or private molecular profiling (Foundation One, n = 7). The CNS TAP tool scores relevant targeted agents by applying multiple variables (i.e., pre-clinical data, clinical data, BBB permeability) to patient specific genomic information and clinical trial availability. In the Michigan cohort, the CNS TAP tool predicted the selected agent 85.7% of the time. The CNS TAP tool predicted the agent independently selected by pediatric neuro-oncologists in the Colorado cohort 50% of the time. Patients with recurrent brain tumors treated with agents predicted by the CNS TAP tool demonstrated a median progression-free survival of 4 months and four patients with recurrent high-grade glioma maintained ongoing partial responses of at least 6 months. The CNS TAP tool is a formalized algorithm to assist clinicians select the optimal targeted therapy for neuro-oncology patients. The CNS TAP tool has relatively high concordance with selected therapies and clinical outcomes in patients receiving targeted therapy in this heterogeneous retrospective cohort were promising.