Low-dose radiotherapy effects the progression of anti-tumor response

Harnessing artificial intelligence to address immune response heterogeneity in low-dose radiation therapy

Low-dose radiation therapy has emerged as a promising modality for cancer treatment because of its ability to stimulate antitumor immune responses while minimizing damage to healthy tissues. However, the significant heterogeneity in immune responses among patients complicates its clinical application, hindering outcome prediction and treatment personalization. Artificial intelligence (AI) offers a transformative solution by integrating multidimensional data such as immunomics, radiomics, and clinical features to decode complex immune patterns and predict individual therapeutic outcomes. This editorial explored the potential of AI to address immune response heterogeneity in low-dose radiation therapy and proposed an AI-driven framework for precision immunotherapy. While promising, challenges, including data standardization, model interpretability, and clinical validation, must be overcome to ensure successful integration into oncological practice.

Whole-body CT scanning radiation improves the immune microenvironment of tumor tissues to enhance the antitumor effect of ICI

OBJECTIVE

The effect of frequent whole-body CT scans during immune checkpoint inhibitor (ICI) therapy on patients' anti-tumor immunity.

METHODS

We conducted a retrospective clinical study aimed to investigate the correlation between the frequency of CT scans during immune checkpoint inhibitor (ICI) therapy and the duration of remission (DOR) of ICI therapy in patients with stage IV non-small cell lung cancer (NSCLC). We constructed a hormonal mouse model and administered immune checkpoint inhibitor (ICI) therapy to mice, and radiated five whole-body CT scans to mice during ICI therapy to observe whether frequent whole-body CT scans had an effect on the antitumor effect of immunotherapy in mice.

RESULTS

The more frequent CT scans during patients' immune checkpoint inhibitor (ICI) treatment the longer the duration of remission (DOR) of ICI treatment. In a mouse model we observed that the addition of whole-body CT scanning radiation had a tendency to inhibit tumor growth in mice compared with the anti-PD-1 group alone.Frequent CT scanning radiation during the application of immune checkpoint inhibitor PD-1 increased the proportion of infiltrating CD8 + T cells in tumor tissues and significantly increased the proportion of IFNγ-secreting CD8 + T cells, and single-cell sequencing of the results also revealed that IFNγ and killing-related genes were significantly upregulated in tumor-infiltrating CD8T cells.

CONCLUSION

To our knowledge this is the first study on the effect of CT scan radiation on ICI.Our findings suggest that multiple CT scans during immune checkpoint inhibitor (ICI) treatment did not promote tumor progression, but instead a trend toward delayed tumor progression was observed.

Effect and mechanism of the miR-1284/EIF4A1 axis on the cGAS-STING pathway under radiotherapy

Background

Gastric cancer (GC) remains a major global health concern, with limited treatment options, especially in advanced stages. Radiotherapy (RT) plays a vital role in GC management, but resistance to DNA damage impedes its effectiveness. MicroRNA-1284 (miR-1284), a tumor suppressor, regulates eukaryotic translation initiation factor 4A1 (EIF4A1), which is involved in DNA damage repair through homologous recombination (HR). This axis has been implicated in enhancing GC cell survival following RT. Additionally, the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway, activated by DNA damage, plays a key role in triggering an anti-tumor immune response. However, the interaction between the miR-1284/EIF4A1 axis, DNA repair, and the cGAS-STING pathway in GC under RT conditions remains unclear. This study aims to investigate how the miR-1284/EIF4A1 axis influences DNA repair and its role in activating the cGAS-STING pathway to enhance RT efficacy in GC.

Methods

A stably expressed messenger miR-1284 cell line was established. Quantitative reverse transcription and western blot were used to examine the expression of miR-1284 and EIF4A1, and the effect of blocking the miR-1284/EIF4A1 axis on the cGAS-STING pathway and interferon-β (IFN-β) in GC cells after RT; cytotoxicity experiments were conducted to explore the mechanism of the miR-1284/EIF4A1 axis in radiation-induced DNA damage repair; animal experiments were conducted to explore the translational application of rocaglamide (RocA) combined with the programmed cell death-ligand 1 (PD-L1) antibody in RT.

Results

The miR-1284/EIF4A1 axis in the GC cells promoted the repair of radiation-induced DNA damage and was associated with the prognosis of GC patients. Blocking this axis delayed the C-terminal binding protein interacting protein (CtIP)-mediated DNA repair, enhanced RT effectiveness, and activated the cGAS-STING pathway, while increasing the rate of apoptosis. In vivo experiments based on RocA binding to PD-L1 antibodies under RT had good biological safety, and thus provide a potential therapeutic strategy for the treatment of GC.

Conclusions

The miR-1284/EIF4A1 axis promotes the repair of DNA damage caused by RT, promotes the activation of the cGAS-STING pathway in GC, and has good biological safety. Our findings provide an important experimental basis for enhancing the anti-tumor immune effect of RT in the treatment of GC.

Radiation from frequent whole-body CT scans induces systemic immunosuppression and immune activation of tumor tissue

OBJECTIVE

This study aims to elucidate the impact of repeated whole-body computed tomography (CT) scans on systemic immunity, the tumor immune microenvironment, and tumor control. This inquiry was prompted by clinical observations indicating a decrease in the levels of IFN-β and IFN-γ in patients' blood following whole-body CT scans.

METHODS

A Lewis lung carcinoma (LLC) mouse model was established and divided into two groups: a control group and a group subjected to multiple whole-body CT scanning radiation (WBCTSs). The study monitored tumor growth trends across both groups and employed a comprehensive set of analytical techniques-including enzyme-linked immunosorbent assay (ELISA), flow cytometry analysis, immunohistochemistry, RNA sequencing, and single-cell sequencing-to assess differences in cytokine profiles (IFN-β and IFN-γ), proportions of key immune cells, and gene expression variations between the groups.

RESULTS

Repeated CT scan radiation does not promote tumor progression. In tumor tissues subjected to multiple CT scans, an increase in the proportion of CD8+ T cells, elevated interferon levels, and up-regulation of genes associated with killing in CD8+ T cells and genes associated with Ifnb in macrophages were observed. In contrast, radiation from multiple whole-body CT scans resulted in a decrease in the proportion of CD8+ T cells in the blood and spleen, a decrease in serum interferon levels, and down-regulation of killing-related genes in CD8+ T cells.

CONCLUSION

Our results suggest that repeated whole-body CT scanning radiation induces systemic immunosuppression and immune activation in tumor tissues. Multiple repeated CT scans do not promote tumor progression.

Enhancing immunotherapy efficacy with synergistic low-dose radiation in metastatic melanoma: current insights and prospects

Recent advances in oncology research have highlighted the promising synergy between low-dose radiation therapy (LDRT) and immunotherapies, with growing evidence highlighting the unique benefits of the combination. LDRT has emerged as a potent tool for stimulating the immune system, triggering systemic antitumor effects by remodeling the tumor microenvironment. Notably, LDRT demonstrates remarkable efficacy even in challenging metastatic sites such as the liver (uveal) and brain (cutaneous), particularly in advanced melanoma stages. The increasing interest in utilizing LDRT for secondary metastatic sites of uveal, mucosal, or cutaneous melanomas underscores its potential efficacy in combination with various immunotherapies. This comprehensive review traverses the journey from laboratory research to clinical applications, elucidating LDRT's immunomodulatory role on the tumor immune microenvironment (TIME) and systemic immune responses. We meticulously examine the preclinical evidence and ongoing clinical trials, throwing light on the promising prospects of LDRT as a complementary therapy in melanoma treatment. Furthermore, we explore the challenges associated with LDRT's integration into combination therapies, addressing crucial factors such as optimal dosage, fractionation, treatment frequency, and synergy with other pharmacological agents. Considering its low toxicity profile, LDRT presents a compelling case for application across multiple lesions, augmenting the antitumor immune response in poly-metastatic disease scenarios. The convergence of LDRT with other disciplines holds immense potential for developing novel radiotherapy-combined modalities, paving the way for more effective and personalized treatment strategies in melanoma and beyond. Moreover, the dose-related toxicities of immunotherapies may be reduced by synergistic amplification of antitumor efficacy with LDRT.

Combination therapy of low-dose radiotherapy and immunotherapy in advanced metastatic nasopharyngeal carcinoma: a case report and literature review

BACKGROUND

Nasopharyngeal cancer (NPC) is a common head and neck malignant tumor, which is difficult to treat at the advanced NPC due to its occult and high metastatic potential to the cervical lymph nodes and distant organs. Low-dose radiotherapy (LDRT) is increasingly being investigated for potential cancer treatment. When combined with immune checkpoint inhibitors, LDRT has been shown to significantly improve the immune microenvironment of tumors, thereby promote the immune attack on tumor cells. However, the therapeutic effect of LDRT combined with immunotherapy in advanced NPC is not well understood. We report a case of a 31-year-old man was diagnosed with advanced metastatic nasopharnygeal non-keratinizing carcinoma (T4N3M1 stage IVb AJCC8th). The patient was treated with a high-dose of radiation therapy combined with LDRT and immunotherapy to inhibit tumor cell proliferation and activate the body's immune system. The initial treatment procedure was as follows: chemotherapy regimen (nedaplatin + docetaxel + fluorouracil) induction, followed by radical radiotherapy for the primary lesion, LDRT for the L5 vertebral body metastasis, and concurrent use of low-dose capecitabine beat chemotherapy and toripalimab immunotherapy. The patient was also administered with human granulocyte-macrophage colony-stimulating factor and aspirin to enhance the immune function. This combination therapy approach alleviated patient symptoms, improved bone changes in the L5 vertebral body and resolved the tumor without any adverse effects signals. The progression-free survival (PFS) has reached 27 months and he is currently stable without tumor recurrence.

CONCLUSION

The combination of chemotherapy and LDRT with aspirin and human granulocyte macrophage colony-stimulating factor improved the disease state of advanced NPC cancer, effectively reducing the level of tumor markers, enhanced the immune function without significant adverse reactions.

Combined treatment of small cell lung cancer using radiotherapy and immunotherapy: Challenges and updates

Currently, chemotherapy remains the standard first- and second-line treatment for small cell lung cancer (SCLC). Research concerning immunotherapy has brought about a remarkable development in the treatment pattern of SCLC. Atirizumab, duvalizumab, atezolizumab, and serplulimab can significantly improve the clinical outcomes of SCLC. Given the rapidly evolving concept that combining immunotherapy with radiotherapy can increase therapeutic effectiveness, clinicians are devoted to further improving local tumor control by integrating immunotherapy with radiotherapy. This paper reviews the research progress in this field to date and explores ways to further enhance the efficacy of this combination therapy. We first discussed that immunotherapy combined with radiotherapy can improve the abscopal effect, progression-free survival, and overall survival rates of SCLC patients. Then, the biomarkers related to the radiation immune microenvironment, such as programmed death ligand-1 (PD-L1), tumor mutational burden (TMB), and the immune function of patients were discussed. Next, we explored the occurrence and underlying mechanisms of immune resistance during radiotherapy implementation. Finally, we clarified that the emerging trend of low-dose radiotherapy help overcome the inhibitory signals that limit T-cell infiltration in the tumor matrix. In summary, considering the rapid development of this field, these combined therapy strategies may have unlimited potential to further improve the efficacy of radiotherapy combined with immunotherapy for patients.

Radiophobia Harm, Its Main Cause, and a Proposed Solution

Background: We are exposed to natural ionizing radiation and other genomic stressors throughout life and radiophobia has caused much harm to society. The main basis for radiophobia is the invalid linear no-threshold (LNT) hypothesis for cancer induction, which the System of Radiological Protection (SRP) is linked to. Largely unknown to the public, evolution-associated genomic stress adaptation (gensadaptation) over many previous generations now provides protection to all lifeforms from low radiation doses. Objective: To help bring about an improved SRP not linked to the invalid LNT hypothesis for radiation-caused health detriment and to promote low-dose radiation therapy for different diseases. Methods: All-solid-cancer mortality risk dose-response relationships for A-bomb survivors were generated based on published LNT-modeling-related results. Dose-response relationships for lung cancer prevention by low-dose radiation were generated by linear interpolation based on published data from a study using > 15,000 mice. Uncertainty characterization was based on Monte Carlo calculations for binomial and Poisson distributions. New dose characterization tools were used for threshold dose-response relationships for radiation-caused cancer mortality. Results: The all-solid-cancer mortality risk for A-bomb survivors transitioned from LNT to threshold-linear when adjusted for key missing uncertainty at low doses. The prevention of lung cancer in mice by low radiation doses depends on the radiation absorbed dose and type. Conclusions: The SRP should be linked to population dose thresholds rather than the invalid LNT hypothesis and small likely harmless radiation doses could possibly be used in treating different diseases.

Environmental Low-Dose Radiation Activates Th1 Immunity through the Mitochondria-STING Pathway

The presence of low-dose radiation (LDR) in the environment has become more prevalent. However, the effect of LDR exposure on the immune system remains elusive. Here, we interestingly found that LDR specifically elevated the percentage of CD4+IFNγ+ Th1 splenocytes, both in vitro and in vivo, without affecting the percentage of CD8+IFNγ+ Tc1 cells and regulatory T cells. A similar phenomenon was found in T cells from peripheral blood. Mechanistically, we found that LDR can induce mitochondrial damage, which stimulated the STING signaling pathway, leading to the enhanced expression of T-bet, the master transcriptional factor of Th1-cell differentiation. The specific STING signal inhibitor can abrogate the effect of LDR on Th1 differentiation, confirming the central role of the STING pathway. To further validate the immunoregulatory role of LDR, we exposed mice with whole body LDR and evaluated if LDR could protect mice against triple-negative breast cancer through enhanced antitumor immunity. As expected, LDR significantly delayed tumor development and promoted cell death. Meanwhile, LDR resulted in increased tumor-infiltrating Th1 cells, while the proportion of Tc1 and Treg cells remained unchanged. Furthermore, the infiltration of antitumor macrophages was also increased. In summary, we revealed that environmental LDR could specifically regulate Th1 T-cell activities, providing critical information for the potential application of LDR in both clinical and nonclinical settings.

Synergistic enhancement of low-dose radiation therapy via cuproptosis and metabolic reprogramming for radiosensitization in in situ hepatocellular carcinoma

BACKGROUND

Radiotherapy (RT) is a primary clinical approach for cancer treatment, but its efficacy is often hindered by various challenges, especially radiation resistance, which greatly compromises the therapeutic effectiveness of RT. Mitochondria, central to cellular energy metabolism and regulation of cell death, play a critical role in mechanisms of radioresistance. In this context, cuproptosis, a novel copper-induced mitochondria-respiratory-dependent cell death pathway, offers a promising avenue for radiosensitization.

RESULTS

In this study, an innovative theranostic nanoplatform was designed to induce cuproptosis in synergy with low-dose radiation therapy (LDRT, i.e., 0.5-2 Gy) for the treatment of in situ hepatocellular carcinoma (HCC). This approach aims to reverse the hypoxic tumor microenvironment, promoting a shift in cellular metabolism from glycolysis to oxidative phosphorylation (OXPHOS), thereby enhancing sensitivity to cuproptosis. Concurrently, the Fenton-like reaction ensures a sustained supply of copper and depletion of glutathione (GSH), inducing cuproptosis, disrupting mitochondrial function, and interrupting the energy supply. This strategy effectively overcomes radioresistance and enhances the therapeutic efficacy against tumors.

CONCLUSIONS

In conclusion, this study elucidates the intricate interactions among tumor hypoxia reversal, cuproptosis, metabolic reprogramming, and radiosensitization, particularly in the context of treating in situ hepatocellular carcinoma, thereby providing a novel paradigm for radiotherapy.

Prospects for Treatment of Lung Cancer Using Activated Lymphocytes Combined with Other Anti-Cancer Modalities

This review explores the significance and prospects of using diverse T-cell variants in the context of combined therapy for lung cancer treatment. Recently, there has been an increase in research focused on understanding the critical role of tumor-specific T lymphocytes and the potential benefits of autologous T-cell-based treatments for individuals with lung cancer. One promising approach involves intravenous administration of ex vivo-activated autologous lymphocytes to improve the immune status of patients with cancer. Investigations are also exploring the factors that influence the success of T-cell therapy and the methods used to stimulate them. Achieving a comprehensive understanding of the characteristics of activated lymphocytes and deciphering the mechanisms underlying their activation of innate anti-tumor immunity will pave the way for numerous clinical trials and the development of innovative strategies for cancer therapy like combined immunotherapy and radiation therapy.

Revolutionizing the treatment for nasopharyngeal cancer: the impact, challenges and strategies of stem cell and genetically engineered cell therapies

Nasopharyngeal carcinoma (NPC) is a distinct malignancy of the nasopharynx and is consistently associated with the Epstein-Barr virus (EBV) infection. Its unique anatomical location and complex aetiology often result in advanced-stage disease at first diagnosis. While radiotherapy (RT) and chemotherapy have been the mainstays of treatment, they often fail to prevent tumour recurrence and metastasis, leading to high rates of treatment failure and mortality. Recent advancement in cell-based therapies, such as chimeric antigen receptor (CAR)-T cell therapy, have shown great promise in hematological malignancies and are now being investigated for NPC. However, challenges such as targeting specific tumour antigens, limited T cell persistence and proliferation, and managing treatment-related toxicities must be addressed. Extensive research is needed to enhance the effectiveness and safety of these therapies, paving the way for their integration into standard clinical practice for better management of NPC and a better quality of life for human health.

Low-dose radiotherapy promotes the formation of tertiary lymphoid structures in lung adenocarcinoma

PURPOSE

A tertiary lymphoid structure (TLS) refers to an organized infiltration of immune cells that is linked to a positive prognosis and improved response to immunotherapy. However, methods that promote TLS formation are limited and challenging to implement in clinical settings. In this study, we aimed to promote the formation and maturation of TLSs in lung adenocarcinoma (LUAD) by combining low-dose radiotherapy (LDRT) with immunotherapy.

METHODS

Tissue sections from 198 patients who had undergone surgery were examined. Risk factors for patient survival were assessed, and the relationship between TLSs and five-year survival was analyzed. The Kras-LSL-G12D spontaneous lung cancer mouse model was used to screen the optimal irradiation dose (0/1/2 Gy whole lung irradiation) for promoting TLS formation. LDRT combined with anti-PD-1 was used to promote the formation and maturation of TLSs.

RESULTS

TLS+, TLSHigh, TLS+GC+ and CD8High within TLS+ were associated with a favorable prognosis. LDRT increased the formation of early TLSs in the Kras-LSL-G12D lung cancer mouse model. In addition, LDRT combined with anti-PD-1 treatment can significantly improve the maturity of TLSs in mouse LUAD, resulting in greater antitumor effects. This antitumor effect was strongly associated with the number of CD8+ T cells within the TLSs.

CONCLUSION

We successfully applied LDRT combined with PD-1 inhibitor therapy for the first time, which increased both the quantity and maturity of TLSs in lung cancer. This approach achieved a promising antitumor effect.

Radiotherapy of high-grade gliomas: dealing with a stalemate

This article discusses the studies on radiotherapy of high-grade gliomas published between January 1, 2022, and June 30, 2022, with special reference to their molecular biology basis. The focus was on advances in radioresistance, radiosensitization and the toxicity of radiotherapy treatments. In the first half of 2022, several important advances have been made in understanding resistance mechanisms in high-grade gliomas. Furthermore, the development of several radiosensitization procedures for these deadly tumors, including studies with small molecule radiosensitizers, new fractionation protocols, and new immunostimulatory agents, has progressed in both the preclinical and clinical settings, reflecting the frantic research effort in the field. However, since 2005 our research efforts fail to produce significant improvements to treatment guidelines for high-grade gliomas. Possible reasons for this stalemate and measures to overcome it are discussed.