In vitro radiotherapy and chemotherapy alter migration of brain cancer cells before cell death

Lnc-RAINY regulates genes involved in radiation susceptibility through DNA:DNA:RNA triplex-forming interactions and has tumor therapeutic potential in lung cancers

Lung cancer is the leading cause of cancer related deaths worldwide. Unfortunately, radiation resistance remains a major problem facing lung cancer patients. Recently, we identified a group of long non-coding RNAs (lncRNAs) known as linc-SPRY3 RNAs, expressed on the Y-chromosome, which play a role in radiation sensitivity by decreasing tumor burden in vitro and in vivo after radiation. In this study, we found that the linc-SPRY3 RNAs are one large lncRNA that we named Radiation Induced Y-chromosome linked long non-coding RNA (lnc-RAINY). Through ATAC-seq and immunoprecipitation experiments, we show that lnc-RAINY interacts with DNA in a triple helix to induce chromatin remodeling and gene expression. We also identified that lnc-RAINY regulates CDC6 and CDC25A expression affecting senescence induction, cell migration patterns, and cell cycle regulation. Furthermore, the administration of Lnc-RAINY encapsulated in FDA-approved nanoparticles into a lung cancer patient-derived xenograft model dramatically reduces tumor progression demonstrating therapeutic potential.

Engineered Cell Microenvironments: A Benchmark Tool for Radiobiology

The development of engineered cell microenvironments for fundamental cell mechanobiology, in vitro disease modeling, and tissue engineering applications increased exponentially during the last two decades. In such context, in vitro radiobiology is a field of research aiming at understanding the effects of ionizing radiation (e.g., X-rays/photons, high-speed electrons, and high-speed protons) on biological (cancerous) tissues and cells, in particular in terms of DNA damage leading to cell death. Herein, the perspective provides a comparative assessment overview of scaffold-free, scaffold-based, and organ-on-a-chip models for radiobiology, highlighting opportunities, limitations, and future pathways to improve the currently existing approaches toward personalized cancer medicine.

Unite and Conquer: Association of Two G-Quadruplex Aptamers Provides Antiproliferative and Antimigration Activity for Cells from High-Grade Glioma Patients

Background: High-grade gliomas remain a virtually incurable form of brain cancer. Current therapies are unable to completely eradicate the tumor, and the tumor cells that survive chemotherapy or radiation therapy often become more aggressive and resistant to further treatment, leading to inevitable relapses. While the antiproliferative effects of new therapeutic molecules are typically the primary focus of research, less attention is given to their influence on tumor cell migratory activity, which can play a significant role in recurrence. A potential solution may lie in the synergistic effects of multiple drugs on the tumor. Objectives: In this study, we investigated the effect of combined exposure to bi-(AID-1-T), an anti-proliferative aptamer, and its analog bi-(AID-1-C), on the migratory activity of human GBM cells. Results: We examined the effects of various sequences of adding bi-(AID-1-T) and bi-(AID-1-C) on five human GBM cell cultures. Our findings indicate that certain sequences significantly reduced the ability of tumor cells to migrate and proliferate. Additionally, the expression of Nestin, PARP1, L1CAM, Caveolin-1, and c-Myc was downregulated in human GBM cells that survived exposure, suggesting that the treatment had a persistent antitumor effect on these cells.

The Bi-(AID-1-T) G-Quadruplex Has a Janus Effect on Primary and Recurrent Gliomas: Anti-Proliferation and Pro-Migration

High-grade gliomas are considered an incurable disease. Despite all the various therapy options available, patient survival remains low, and the tumor usually returns. Tumor resistance to conventional therapy and stimulation of the migratory activity of surviving cells are the main factors that lead to recurrent tumors. When developing new treatment approaches, the effect is most often evaluated on standard and phenotypically depleted cancer cell lines. Moreover, there is much focus on the anti-proliferative effect of such therapies without considering the possible stimulation of migratory activity. In this paper, we studied how glioma cell migration changes after exposure to bi-(AID-1-T), an anti-proliferative aptamer. We investigated the effect of this aptamer on eight human glioma cell cultures (Grades III and IV) that were derived from patients' tumor tissue; the difference between primary and recurrent tumors was taken into account. Despite its strong anti-proliferative activity, bi-(AID-1-T) was shown to induce migration of recurrent tumor cells. This result shows the importance of studying the effect of therapeutic molecules on the invasive properties of glioma tumor cells in order to reduce the likelihood of inducing tumor recurrence.

Understanding Glioblastoma Signaling, Heterogeneity, Invasiveness, and Drug Delivery Barriers

The most prevalent and aggressive type of brain cancer, namely, glioblastoma (GBM), is characterized by intra- and inter-tumor heterogeneity and strong spreading capacity, which makes treatment ineffective. A true therapeutic answer is still in its infancy despite various studies that have made significant progress toward understanding the mechanisms behind GBM recurrence and its resistance. The primary causes of GBM recurrence are attributed to the heterogeneity and diffusive nature; therefore, monitoring the tumor's heterogeneity and spreading may offer a set of therapeutic targets that could improve the clinical management of GBM and prevent tumor relapse. Additionally, the blood-brain barrier (BBB)-related poor drug delivery that prevents effective drug concentrations within the tumor is discussed. With a primary emphasis on signaling heterogeneity, tumor infiltration, and computational modeling of GBM, this review covers typical therapeutic difficulties and factors contributing to drug resistance development and discusses potential therapeutic approaches.

Development of In Vitro Assays for Advancing Radioimmunotherapy against Brain Tumors

Glioblastoma (GBM) is the most common primary brain tumor. Due to high resistance to treatment, local invasion, and a high risk of recurrence, GBM patient prognoses are often dismal, with median survival around 15 months. The current standard of care is threefold: surgery, radiation therapy, and chemotherapy with temozolomide (TMZ). However, patient survival has only marginally improved. Radioimmunotherapy (RIT) is a fourth modality under clinical trials and aims at combining immunotherapeutic agents with radiotherapy. Here, we develop in vitro assays for the rapid evaluation of RIT strategies. Using a standard cell irradiator and an Electric Cell Impedance Sensor, we quantify cell migration following the combination of radiotherapy and chemotherapy with TMZ and RIT with durvalumab, a PD-L1 immune checkpoint inhibitor. We measure cell survival using a cloud-based clonogenic assay. Irradiated T98G and U87 GBM cells migrate significantly (p < 0.05) more than untreated cells in the first 20−40 h post-treatment. Addition of TMZ increases migration rates for T98G at 20 Gy (p < 0.01). Neither TMZ nor durvalumab significantly change cell survival in 21 days post-treatment. Interestingly, durvalumab abolishes the enhanced migration effect, indicating possible potency against local invasion. These results provide parameters for the rapid supplementary evaluation of RIT against brain tumors.