[Effect of ileostomy on the clinical outcomes of children with very early onset inflammatory bowel disease]

To explore the effect of ileostomy on clinical outcomes of children with very early onset inflammatory bowel disease(VEO-IBD). The clinical data of 11 children with VEO-IBD who underwent ileostomy in the Department of Gastroenterology of the Affiliated Children's Hospital of Zhengzhou University from January 2016 to December 2022 were retrospectively analyzed, and the clinical characteristics and outcomes were analyzed. A total of 11 cases were included, including 7 males and 4 females, aged 3.0 (0.9, 8.0) months. The main clinical manifestations were fever and diarrhea, with L2 type the main lesion site (according to the Paris classification of childhood Crohn's disease). There were 7 cases of gene type interleukin (IL)-10RA. After VEO-IBD ileostomy, the disease site, incidence of growth disorders, the weighted children's Crohn's disease activity index, the simplified endoscopic score of Crohn's disease, and severe mucosal inflammation activity rate were all lower than those before ileostomy (all P<0.05). The postoperative inflammatory indicators and factors were lower than those before ileostomy (all P<0.05). The mucosal barrier indicators after ileostomy were increased than before (all P<0.05). The nutritional evaluation indicators after ileostomy were improved (P<0.05). Ileostomy can reduce inflammatory response of VEO-IBD, improve intestinal mucosal barrier, reduce disease activity, and improve nutritional status.

[Effect of recombinant human thrombin for hemostasis in liver resection: a randomized controlled phase Ⅲ clinical trial]

Objective: To evaluate the hemostatic efficacy, safety and immunogenicity of recombinant human thrombin in the treatment of liver wounds that still ooze after conventional surgical hemostasis. Methods: A multicenter, stratified randomized, double-blind, placebo-controlled phase Ⅲ trial with a planned enrollment of 510 subjects at 33 centers, with a 2∶1 randomization to the thrombin group versus the placebo group. An interim analysis will be conducted after approximately 70% of the subjects have completed the observation period. The primary efficacy endpoint was the rate of hemostasis within 6 minutes at the point of bleeding that could be evaluated. Safety analysis was performed one month after surgery, and the positive rates of anti-drug antibody (ADA) and neutralizing antibody were evaluated. Results: At the interim analysis, a total of 348 subjects had been randomized and received the study drug (215 were male and 133 were female). They were aged 19-69 (52.9±10.9)years. Among them, 232 were in the thrombin group and 116 were in the placebo group, with balanced and comparable demographics and baseline characteristics between the two groups. The hemostasis rate at 6 minutes was 71.6% (95%CI:65.75%-77.36%) in the thrombin group and 44.0% (95%CI: 34.93%-53.00%) in the placebo group, respectively (P<0.001). No grade≥3 drug-related adverse events and no drug-related deaths were reported from the study.No recombinant human thrombin-induced immunologically-enhanced ADA or immunologically-induced ADA was detected after topical use in subjects. Conclusion: Recombinant human thrombin has shown significant hemostatic efficacy and good safety in controlling bleeding during liver resection surgery, while also demonstrating low immunogenicity characteristics.

Observation of New Baryons in the Ξ_{b}^{-}π^{+}π^{-} and Ξ_{b}^{0}π^{+}π^{-} Systems

The first observation and study of two new baryonic structures in the final state Ξ_{b}^{0}π^{+}π^{-} and the confirmation of the Ξ_{b}(6100)^{-} state in the Ξ_{b}^{-}π^{+}π^{-} decay mode are reported using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9  fb^{-1}. In addition, the properties of the known Ξ_{b}^{*0}, Ξ_{b}^{'-} and Ξ_{b}^{*-} resonances are measured with improved precision. The new decay mode of the Ξ_{b}^{0} baryon to the Ξ_{c}^{+} π^{-} π^{+} π^{-} final state is observed and exploited for the first time in these measurements.

Precision Measurement of CP Violation in the Penguin-Mediated Decay B_{s}^{0}→ϕϕ

A flavor-tagged time-dependent angular analysis of the decay B_{s}^{0}→ϕϕ is performed using pp collision data collected by the LHCb experiment at the center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 6  fb^{-1}. The CP-violating phase and direct CP-violation parameter are measured to be ϕ_{s}^{ss[over ¯]s}=-0.042±0.075±0.009  rad and |λ|=1.004±0.030±0.009, respectively, assuming the same values for all polarization states of the ϕϕ system. In these results, the first uncertainties are statistical and the second systematic. These parameters are also determined separately for each polarization state, showing no evidence for polarization dependence. The results are combined with previous LHCb measurements using pp collisions at center-of-mass energies of 7 and 8 TeV, yielding ϕ_{s}^{ss[over ¯]s}=-0.074±0.069  rad and |λ|=1.009±0.030. This is the most precise study of time-dependent CP violation in a penguin-dominated B meson decay. The results are consistent with CP symmetry and with the standard model predictions.

[Research progress on the mechanism of action of mitophagy in the occurrence and development of liver cancer]

Mitophagy, as an important link in maintaining mitochondrial homeostasis and environmental homeostasis in the liver, can remove damaged mitochondria and provide energy through autophagy and other processes. Additionally, it plays a dual role in the occurrence and development of liver cancer and can affect the therapeutic effect of liver cancer through a variety of signaling pathways. This article reviews the relationship between mitophagy and hepatitis B virus infection, liver cancer occurrence and development, liver cancer stem cells, mitochondrial division and fusion, therapeutic resistance and invasiveness of liver cancer, and other aspects.

Measurement of the Λ_{b}^{0}→Λ(1520)μ^{+}μ^{-} Differential Branching Fraction

The branching fraction of the rare decay Λ_{b}^{0}→Λ(1520)μ^{+}μ^{-} is measured for the first time, in the squared dimuon mass intervals q^{2}, excluding the J/ψ and ψ(2S) regions. The data sample analyzed was collected by the LHCb experiment at center-of-mass energies of 7, 8, and 13 TeV, corresponding to a total integrated luminosity of 9  fb^{-1}. The result in the highest q^{2} interval, q^{2}>15.0  GeV^{2}/c^{4}, where theoretical predictions have the smallest model dependence, agrees with the predictions.

Molecular Imaging of Radiation-Induced Lung Injury Using [18F]AlF Labeled Polypeptide Targeting C-X-C-Chemokine-Receptor-Type-4

PURPOSE/OBJECTIVE(S)

Radiation-induced lung injury (RILI) is a severe side effect of radiotherapy (RT) for thoracic malignancies and we currently lack established means for the early detection of RILI. In this study, we synthesized a new tracer, [18F]AlF-NOTA-QHY-04, targeting C-X-C-chemokine-receptor-type-4 (CXCR4) and investigated the feasibility of using this tracer in positron emission tomography combined with computed tomography (PET/CT) for detecting RILI.

MATERIALS/METHODS

An RILI model was established using a high-dose single RT (50 Gy/Fraction) to the right lung of female Wistar rats. Experimental animals were scanned with [18F]AlF-NOTA-QHY-04 PET/CT and [18F]FDG PET/CT at various time-points post-RT. MicroCT imaging was conducted weekly till 11 weeks post-RT. Dynamic, competition, autoradiography and histopathological studies were performed on day 14 post-RT. Biodistribution study was further performed on day 18 post-RT. Lung QHY-04 uptake was analyzed in twelve patients with radiation pneumonia, developed during or after thoracic RT.

RESULTS

The yield of [18F]AlF-NOTA-QHY-04 was 28.5-43.2%, and the specific activity was 27-33 GBq/μmol. Significantly increased [18F]AlF-NOTA-QHY-04 uptake in the damaged lung compared with that in the normal lung was observed in the experimental animal model on 6 post-RT and peaked on day 14 post-RT (0.96 ± 0.06 vs. 0.50 ± 0.05 %ID/mL, P<0.05), whereas no apparent uptake of [18F]FDG was shown on day 7 and 15 post-RT. Significant intense [18F]AlF-NOTA-QHY-04 uptake was confirmed by autoradiography. No significant difference in CT density was observed between the damaged and normal lung tissues until six weeks post-RT. Immunofluorescence staining demonstrated expression of CXCR4 was significantly increased in the damaged lung tissue, which correlated with results obtained from hematoxylin-eosin and Masson's trichrome staining. Maximum standardized uptake values (SUVmax) were significantly higher in the irradiated lung compared with that in the normal lung in 12 patients with radiation pneumonia (3.07 ± 0.86 vs. 0.585 ± 0.17, P<0.001). SUVmax of patients with grade 2 RILI was significantly higher than that of patients with grade 1 RILI (3.30 ± 0.65 vs. 1.64 ± 0.08, P<0.05).

CONCLUSION

This study indicated that [18F]AlF-NOTA-QHY-04 PET/CT imaging can detect RILI noninvasively and earlier than [18F]FDG PET/CT in a rat model. Clinical studies verified its' feasibility, suggesting the clinical potential of [18F]AlF-NOTA-QHY-04 as a PET/CT tracer for early monitoring of RILI.

Overcoming Radio-Immunotherapy Treatment Resistance through ILT4 Blockade and Reversal of HFRT Induced CXCL1-CXCR2 Axis Activation and Tumor-Associated Macrophage Immunosuppression

PURPOSE/OBJECTIVE(S)

Immunotherapy combined with radiotherapy (iRT) has unlimited potential, but up to 60% of cancer patients do not benefit from it. Enhancing the anti-tumor immune stimulatory effect triggered by radiotherapy is the key to overcome iRT resistance. Immunoglobulin-like transcript (ILT) 4 is a potential immune checkpoint molecule, highly expressed in various tumor cells, but its role in radiotherapy is still unknown. This study confirmed the role and molecular mechanism of ILT4 in suppressing radiotherapy immunosuppressive microenvironment formation and promoting tumor radiotherapy resistance. We propose a new therapeutic strategy that block ILT4 to enhance the efficacy of radiotherapy, and cooperate with radiotherapy to reverse immunotherapy resistance.

MATERIALS/METHODS

Using multiplex immunohistochemistry, we analyzed ILT4 expression, tumor-associated macrophage (TAM) /T cell phenotype and quantity in tumor patient treated with SBRT. Using mice subcutaneous tumor models, Single-cell RNA sequencing and multiplex flowcytometry, we assessed the role of ILT4 inhibition and hyper-fractionated radiotherapy (HFRT) on preventing tumor growth and immune escape. The molecular signaling and cytokines regulated by ILT4 under HFRT were analyzed by transcriptome sequencing and further verified by molecular experiments. By establishing cancer cell/TAM co-culture system in vitro, using CXCL1 protein or CXCR2 inhibitor and macrophage/CD8+ T cell deletion antibody in vivo, we identified the downstream pathway and cytokine of ILT4 to enhancing HFRT -induced TAM immune response.

RESULTS

In the tumor specimens of NSCLC patients treated with SBRT, we found that high ILT4 expression predicted poor progression-free survival and more M2-TAM recruitment. Among the C57BL/6 mice model, ILT4 inhibition in cancer cells reduced HFRT mediated M2-TAMs accumulation, and to sustain activation and proliferation of CD8+ T cells, and eventually suppressed tumor progression. Mechanistically, RT promoted ILT4 expression, which subsequently induced NF-κB pathway activation and CXCL1 secretion to enhance M2-TAMs migration in vitro. Using CXCL1 protein or CXCR2 inhibitor administration, inferring that ILT4 promotes TAMs migration via NF-κB-CXCL1-CXCR2 axis. Consistently, depletion of TAMs blocked the T cell function impairment and radiotherapy resistance induced by ILT4 in vivo. Importantly, targeting ILT4 potentiated the effect of radiotherapy, overcomes radio-immunotherapy treatment resistance.

CONCLUSION

ILT4 mediates HFRT-induced M2-like TAMs recruitment and subsequently T cell response impairment by regulating NF-κB-CXCL1-CXCR2 axis. ILT4 is an attractive drug target for enhancing radiotherapy and overcomes radio-immunotherapy treatment resistance.

Metformin Antagonizes Radiotherapy-Induced Anti-Tumor Effects via Inhibition of cGAS-STING Pathway Mediated Immune Responses

PURPOSE/OBJECTIVE(S)

Radiotherapy induced anti-tumor effects depend on both direct tumor cell death caused by radiation and immune activation mediated by cGAS-STING pathway. Metformin (MTF), which could augment the tumoricidal efficiency of radiation, is indicated to be a radiosensitizer by basic research. However, several large prospective clinical trials proved otherwise. In present study, we intend to interrogate the effects of MTF on radiotherapy-induced anti-tumor immune responses and try to explain the inconsistent outcomings of radiotherapy combined with MTF in basic research and clinical practice.

MATERIALS/METHODS

To explore the effects of MTF on radiotherapy induced anti-tumor effects, tumor models were established using E0771, B16F10 and LLC cell lines in both immunocompetent and immunodeficient mice. To investigate the composition and function of immune cells in tumor microenvironments, single-cell transcriptome sequencing of CD45+ cells sorted from tumor microenvironments were carried out, and flow cytometry and multiple immunofluorescence analysis were then performed for validation. To reveal the possible mechanisms, tumor cells were subjected to radiotherapy in the presence or absence of MTF in vitro, and RNA-sequencing was then employed followed by subsequent validation with western blotting, real-time qPCR and flow cytometry.

RESULTS

We found that systematic administration of MTF could significantly inhibit radiotherapy-induced anti-tumor effects in immunocompetent mouse models. Single cell sequencing of CD45+ cells sorted from tumor microenvironments and further validation showed that administration of MTF dramatically attenuated the infiltration and cytotoxic capacity of CD8+ T cells after radiotherapy. cGAS-STING pathway in tumor cells was required for maximum efficiency of radiotherapy, while MTF curbed cGAS-STING pathway after radiotherapy in a dose-dependent pattern by enhancing autophagy and reducing cytoplasmic mitochondrial DNA accumulation, which contributed to compromised anti-tumor effects.

CONCLUSION

Our findings indicated that MTF could antagonize radiotherapy-mediated anti-tumor effects by inhibiting the activation of cGAS-STING pathway and subsequent immune responses, which may partially explain the unsatisfied outcomes of radiotherapy combined with MTF in clinical practices. Since the anti-tumor effects of radiotherapy rely not only on the tumor-killing efficiency of radiation but also on systematic immune responses, our findings suggest that cautions are needed when MTF is administrated with radiotherapy in clinical practice.

Targeting XPO1 Combined with Radiotherapy to Enhance Systemic Anti-tumor Effects in Non-Small Cell Lung Cancer

PURPOSE/OBJECTIVE(S)

The combination of radiation and radiosensitizing chemotherapeutic agents have shown promising anti-tumor effects in NSCLC. Acting as an oncogenic driver, XPO1 is frequently overexpressed and/or mutated in lung cancer. Thus, suppression of XPO1-mediated nuclear export presents a unique therapeutic strategy. We hypothesize that XPO1 inhibition combined with radiotherapy (XRT) may remodel the tumor immune microenvironment (TIME) and reduce radioresistance, thus enhance systemic anti-tumor effects.

MATERIALS/METHODS

Herein, we optimized a small molecule inhibitor, WJ01024, which can bind to XPO1 and antagonize its activity to inhibit nuclear export. In the C57BL/6 mouse subcutaneous tumor model, we evaluated the ability of different treatment regimens containing oral WJ01014 single or combined with XRT (one fractions of 15 Gy) in tumor control and tumor recurrence inhibition. The effects of each treatment regimen on the alterations of immunophenotypes, including the quantification, activation, proliferative capacity, exhaustion marker expression, and memory status, were evaluated by flow cytometry.

RESULTS

In our study, we found that the overexpression of XPO1 was associated with poor prognosis and survival in radioresistant patients with NSCLC. The combination therapy of WJ01024 and XRT resulted in an increase of apoptosis and a decrease of proliferation compared to monotherapy, which was closely correlated with tumor regression and improved survival in the C57BL/6 mouse subcutaneous tumor model. Notably, we found that WJ01024 were shown to enhance the therapeutic effect of XRT by remodeling TIME. Compared with XRT, the addition of WJ01024 increased the infiltration and proliferation of radiation-stimulated CD8+ T cells, which especially promoted the production of interferon-γ and granzyme B. Moreover, the combination therapy also reversed the immunosuppressive effect of radiation on the percentage of Tregs and exhausted T cells in mouse xenografts. Thus, the TIME was significantly improved in combination therapy. Strikingly, mechanistic studies suggested that the activation of cyclic GMP-AMP synthase/stimulator of interferon genes (cGAS/STING) signaling pathway is required to reshape TIME and produce synergistic anti-tumor effect with the combination of WJ01024 and XRT.

CONCLUSION

Our findings suggest that WJ01024 might be a potential synergistic treatment for radiotherapy to control the proliferation of NSCLC cells, promote tumor regression and prolong survival in mouse model of NSCLC by activating cGAS/STING signaling, and this in turn potentiate the immune microenvironment.

Dissecting Systemic T Cell Responses after Stereotactic Ablative Radiotherapy in NSCLC by Single-Cell RNA and T Cell Receptor Sequencing

PURPOSE/OBJECTIVE(S)

There is accumulating evidence that stereotactic ablative radiotherapy (SABR) modulates immune responses to cancer; combining SABR and immunotherapy could promote the abscopal effect, but the precise effects of SABR on patients' systemic T cells is unclear. Here, we investigated SABR-induced systemic T cell response in early-stage non-small cell lung cancer (NSCLC) by single-cell RNA and T cell receptor sequencing.

MATERIALS/METHODS

We performed single-cell RNA and T cell receptor sequencing on 29,439 T cells from four pairs of peripheral blood before and after SABR in early-stage NSCLC patients. Cell clustering and dimensionality reduction, SingleR, feature genes score, and TCR profiling analyses were used to investigate the heterogeneity of T cells and their changes following SABR.

RESULTS

We identified fourteen T cell subtypes using unsupervised graph-based clustering of uniform manifold approximation and projection. By comparing the gene set scores of CD8_TE and CD8_EM pre- and post-SABR, we found both cytotoxic and inhibitory scores were significantly elevated in CD8_TE (both P < 0.001), while cytotoxic score was significantly increased in CD8_EM (P < 0.001) after SABR. We also found that CD4_TE showed increased cytotoxic scores and decreased Treg scores (P < 0.001 and < 0.05, respectively), while Treg cells showed decreased inhibitory and Treg scores (P < 0.001 and <0.01, respectively) after SABR. The proportion of large TCR clones was higher after SABR, which was accompanied by a decrease in proportion of single clones. When we compared the transcriptomes of CD8_TE cells between the single, small and large clones post-SABR, we found high expression of GZMB and KLRC3 in cells with large clones, and GZMK, IL7R, and SELL in small and single clones. This suggested that T cells after SABR with large clones may have higher cytotoxicity than those with small and single clones.

CONCLUSION

Our study identified systemic T cell activation after SABR at single-cell resolution, providing unprecedented insight into the immune-modulatory role of SABR in early-stage NSCLC.

Single-Cell RNA Sequencing Reveals a Subset of cMAS can Aggravate RIHD through CXCL1-CXCR2 Axis

PURPOSE/OBJECTIVE(S)

Radiation induced heart disease (RIHD) is any form of cardiac toxicity induced by radiation therapy (RT) for thoracic cancers. Our previous studies have shown that RT obviously contributed to cardiovascular diseases-specific death over 3 years while RT became protective in the short term within 2 years survival in non-small cell lung cancer patients. Here, single cell RNA sequencing (scRNA-seq) was performed to identify various cell subsets and investigate their functions and dynamics in RIHD which offered several targets for early clinical interventions to alleviate RIHD.

MATERIALS/METHODS

Based on evaluation of histopathological characteristics, ejection fraction and serum levels of cardiac injury biomarkers, we have established mouse models during different stages to simulate clinical RIHD progression. Hence, we performed single cell RNA-sequencing of RIHD models to characterize the diversity within specific cell types and obtain basic information of differently expressed genes (DEGs). We investigated the role of several cell clusters and DEGs in RIHD through bioinformatics analysis and experimental verification. In vivo, mouse models were given intraperitoneal injection of CXCR2 inhibitor. Bone marrow macrophages and primary cardiac fibroblasts were extracted for in vitro experiments.

RESULTS

RIHD processes were divided into acute injury, compensation and decompensation stage. Transcriptomes of 31769 single cells from cardiac suspension have been profiled. Analysis of scRNA-seq revealed that there were 30 cell clusters participating in RIHD. The fraction of cell populations varied greatly at three stages which indicated RIHD was a dynamic process and each cell cluster functioned differently at different stages. Notably, we observed cardiac resident macrophages (cMAS) subset accounted for the highest fraction during the compensatory period and decreased in decompensation period. Pseudotime analysis showed cMAS had a different developmental trajectory compared to myeloid derived cells. Moreover, CXCR2 was significantly expressed in cMAS cluster. Ligand-receptor interaction results suggested that CXCL1 secreted by cardiac fibroblasts bind primarily to CXCR2+ cMAS and participated in the formation of the extracellular matrix (ECM) related to cardiac fibrosis. Moreover, cardiac fibrosis of RIHD models were relieved after CXCR2 inhibitor treatment. CXCL1 expression in primary cardiac fibroblast elevated after RT.

CONCLUSION

The identification of main cell clusters provided a new insight to investigate RIHD through dynamics of cell phenotypes and cell-cell communications during RIHD processes. In compensation stage, CXCR2+ cMAS could be activated by CXCL1 secreted by cardiac fibroblasts. Both were associated with ECM and contribute to the decompensation stage.

IL-1β+ Tumor Associated Macrophages Induced by Type I Interferon Initiates Radiotherapy-Mediated Abscopal Effect

PURPOSE/OBJECTIVE(S)

Both experimental and clinical studies have proved that radiotherapy can lead to not only local control of irradiated tumors, but also tumor regression of non-irradiated area, termed as abscopal effect. Abscopal effect has been attributed to radiotherapy-induced innate and adaptive anti-tumor immune responses. However, the detailed molecular mechanisms and key cellular components are still unclear. So, the purpose of this study is to reveal the key molecular mechanisms and essential cells in inducing abscopal effect.

MATERIALS/METHODS

Bilateral MC38 subcutaneous tumor mouse models were established, and primary tumors were subjected to one fraction of 15Gy. CD45+ cells were sorted from both primary and abscopal tumors 3-, 7-, 17- and 24-day post radiotherapy respectively and subjected to single-cell RNA sequencing followed by standard bioinformatic analysis with R studio. To verify the findings, flow cytometry, mIHC and real-time qPCR were carried out to analyze the cellular and molecular components in tumor microenvironments. Cellular depletion experiments and conditional knockout mice were finally employed to confirm key mechanisms that contribute to abscopal effect.

RESULTS

The primary and abscopal immune microenvironments showed different repertoires time-dependently. Radiotherapy induced durable type I interferon (IFN-I) responses with dramatic infiltration and activation of CD8+ T cells and tumor associated macrophages (TAMs) in primary tumors. However, in abscopal tumors, we found that TAMs rather than CD8+ T cells were the predominant population activated in early stages (3- and 7-day post radiotherapy), and functional CD8+ T cells enriched until late stages (24-day post radiotherapy). Thorough analysis of scRNA-seq and experimental validation discovered a unique subset of TAMs characterized by high expression of IL-1β emerged as early as 3-day post radiotherapy in both primary and secondary tumor immune microenvironments, termed as IL-1β+ TAMs herein. IL-1β+ TAMs were the main activated component in abscopal tumors in early stage, and strongest respondent to IFN-I pathway. Abscopal effect was significantly attenuated when IFN-I response was abolished in either primary or abscopal tumors or TAMs were depleted from abscopal tumors.

CONCLUSION

Our data identified a subset of immune cells, IL-1β+ TAMs, and IFN-I as the essential cellular and molecular components that contribute to abscopal effect. Mechanically, radiotherapy-induced dramatical IFN-I response in primary tumors lead to enrichment of IL-1β+ TAMs, which initiated the anti-tumor immune response in abscopal tumors. All these findings provided theoretical basis for understanding and improving radiotherapy-induced abscopal effect.

Spatial Proteome Analysis Identifies Lymphocyte CD44 as a Biomarker Associated with SBRT Resistance in Early-Stage Non-Small Cell Lung Cancer

PURPOSE/OBJECTIVE(S)

To discover and validate spatially-resolved protein markers associated with resistance to SBRT in early-stage NSCLC patients.

MATERIALS/METHODS

We initially evaluated a discovery cohort of 44 early-stage NSCLC patients treated with SBRT as first-line treatment at the Shandong cancer hospital. Using the GeoMx DSP system, 71 proteins were measured in five molecular compartments (tumor, leukocyte, lymphocyte, macrophage, and stroma) on pre-treatment samples. Candidate biomarkers were orthogonally validated with the Gem AQUA method of quantitative immunofluorescence (QIF). For internal independent cohort validation, we assessed pre-treatment samples derived from 150 NSCLC patients who receive radiotherapy. We further analyzed 100 radiotherapy untreated patients with operable NSCLC to address prognostic significance.

RESULTS

Using continuous log-scaled data, we identified CD44 expression in the lymphocyte compartment (CD3+) as a novel predictor of poor progression-free survival (PFS) (multivariate HR = 7.323, p = 0.0079) and overall survival (OS) (multivariate HR = 8.65, p = 0.028) in the discovery set. High CD44 expression in the tumor compartment (pan-cytokeratin, CK+) predicted significantly shorter OS (multivariate HR = 2.208, p = 0.0212), with no significant difference in PFS. We validated by QIF that lymphocyte CD44 levels were associated with resistance to SBRT therapy and prognostic for poor outcomes. Using QIF in an independent radiotherapy treated cohort, we validated that CD44 levels in the lymphocyte compartment were associated with poor PFS and OS. High lymphocyte cell CD44 was not prognostic in non-radiotherapy-treated cohort. Using DSP data, intratumoral regions with elevated lymphocyte cell CD44 expression showed prominent upregulation of CD127, ARG1 and VISTA in the discovery Cohort.

CONCLUSION

In conclusion, we identified and validated lymphocyte cell CD44 as a biomarker indicative of resistance to SBRT or radiotherapy in patients with NSCLC. Further evaluation is warranted to address the predictive value of lymphocyte cell CD44 in multi-institutional studies and clinical trials.

Irradiated Tumor Cells-Derived Exosomes Modulate Macrophage Polarization by Targeting SHP-2 Mediated Metabolic Reprogramming

PURPOSE/OBJECTIVE(S)

Tumor-associated macrophages (TAMs) constitute a plastic and heterogeneous cell population of the tumor microenvironment (TME) that can regulate tumor proliferation and support resistance to therapy, constituting promising targets for the development of novel anticancer agents. The efficacy of radiotherapy, a mainstay of cancer treatment, can strongly influence TAMs recruitment and phenotype. Our previous results demonstrated that SHP-2 and PD-L1 inhibition combined with radiotherapy enhances systemic antitumor effects in non-small cell lung cancer (NSCLC). Especially, SHP-2 has an important effect on the polarization of TAM in the context of radiotherapy. However, the immune mechanisms of SHP-2 in TAM remain largely unknown, and this leads us to implement this project.

MATERIALS/METHODS

Transmission electron microscopy and differential ultracentrifugation were used to verify the existence of exosomes. The bone marrow-derived macrophages (BMDM) and peritoneal macrophages (PM) were derived from C57BL/6 mice for vitro tests. In vivo and in vitro assays were used to identify roles of exosomal miRNA targeting SHP-2. To investigate the regulating function of SHP-2 in TAMs, co-culture experiments, qPCR, Western Blot, Flow Cytometry and Oxygraph-2k were employed. And we also explore tumor growth and tumor environment changes in SHP-2 flox/floxLyz-Cre+/- (CKO) mice.

RESULTS

We found that irradiated tumor cells-derived exosomes reprogramed their energy metabolism and polarized primary macrophages to an anti-inflammatory phenotype. Furthermore, SHP-2 in macrophages was a direct target of exosomal miR-138-5p from irradiated tumor cells. In vitro study also demonstrates that miR-138-5p can down-regulate SHP-2 in the BMDMs and PMs. Further research has shown that SHP-2 negatively regulated glycolysis through dephosphorylating Pyruvate kinase M2 (PKM2) at the Tyr105 site. In addition, SHP-2 can inhabit PKM2 translocation to the nucleus by dephosphorylating PKM2 at the Ser37 site. Thus, the SHP099 (a SHP-2 inhibitor) can uptake and utilization of glucose by SHP-2/PKM2(Tyr105) (Ser37)/β-catenin/LDHA/Glut-1 axis, suggesting that SHP099 plays positive roles on glycolysis and M1-polarized. In vivo study showed that SHP-2 flox/floxLyz-Cre+/- (CKO) mice display enhanced control of solid tumor growth, accompanied by increased the proportion of M1-like macrophages.

CONCLUSION

Our study demonstrates that exosomal miR-138-5p from irradiated tumor cells can modulate macrophage polarization by targeting SHP-2. And SHP-2 negatively regulates glycolysis and polarize macrophage to an M2 phenotype by SHP-2/PKM2(Tyr105) (Ser37)/β-catenin/LDHA/Glut-1 axis.

High Dose Hyperfractionated Thoracic Radiotherapy vs. Standard Dose for Limited Stage Small-Cell Lung Cancer: A Multicenter, Open-Label Randomized, Phase 3 Trial

PURPOSE/OBJECTIVE(S)

Limited stage small-cell lung cancer (LS-SCLC) is associated with poor prognosis. We aimed to assess the efficacy and safety of high-dose, hyperfractionated thoracic radiotherapy of 54 Gy in 30 fractions compared with standard dose (45 Gy in 30 fractions) as a first-line treatment for LS-SCLC.

MATERIALS/METHODS

The study was an open-label, randomized, phase 3 trial, done at 16 public hospitals in China. Key inclusion criteria were patients aged 18-70 years, with previously histologically or cytologically confirmed LS-SCLC, previously untreated or received 1-2 courses of intravenous cisplatin (75 mg/m²of body-surface area, on day 1 or divided into two days of each cycle) or carboplatin (area under the curve of 5 mg/mL per min, day 1 of each cycle)and intravenous etoposide (100 mg/m²of body-surface area, on days 1-3 of each cycle), and an Eastern Cooperative Oncology Group (ECOG) performance status of 0-1.Eligible patients were randomly assigned (1:1) to receive volumetric-modulated arc radiotherapy (VMAT) of 45 Gy in 30 fractions or the simultaneous integrated boost VMAT (SIB-VMAT) of 54 Gy in 30 fractions to the primary lung tumor and lymph node metastases starting 0-42 days after the first chemotherapy course. Both groups of patients received thoracic radiotherapy twice per day and 10 fractions per week. Prophylactic cranial radiation (PCI, 25 Gy in 10 fractions) was implemented to patients with responsive disease. The primary endpoint was overall survival. Safety was analyzed in the as-treated population.

RESULTS

Between June 30, 2017, and April 6, 2021, 224 eligible patients were enrolled and randomly assigned to 54 Gy (n = 108) or 45 Gy (n = 116). Median follow-up for the primary analysis was 45 months (IQR 41-48). Median overall survival was significantly improved in the 54 Gy group (62.4 months) compared with the 45 Gy group (43.1 months; p = 0.001). Median progression-free survival was significantly improved in the 54 Gy group (30.5 months) compared with the 45 Gy group (16.7 months; p = 0.044). The most common grade 3-4 adverse events were neutropenia (30 [28%] of 108 patients in the 54 Gy group vs 27 [23%] of 116 patients in the 45 Gy group), neutropenic infections (6 [6%] vs 2 [2%]), thrombocytopenia (13 [12%] vs 12 [10%]), anemia (6 [6%] vs 4 [3%]), and esophagitis (1 [1%] vs 3 [3%]). Treatment-related serious adverse events occurred in 9 [8%] patients in the 54 Gy group and 16 [14%] patients in the 45 Gy group. There were one treatment-related deaths in 54 Gy group (myocardial infarction).

CONCLUSION

Compared with standard thoracic radiotherapy dose of 45 Gy, the high dose of 54 Gy improved overall survival and progression-free survival without increasing toxicities in patients with LS-SCLC, supporting twice-daily hyperfractionated thoracic radiotherapy of 54 Gy with concurrent chemotherapy is an alternative treatment option for LS-SCLC. This study is complete and registered with ClinicalTrials.gov, NCT03214003.

TFAM Modulates Cardiomyocytes Pyroptosis Induced by Ionizing Radiation through mtDNA/TLR9/NF-kB Pathway

PURPOSE/OBJECTIVE(S)

Mitochondrial transcription factor A (TFAM) is a pivotal factor for regulating mitochondrial DNA (mtDNA) replication, transcription and biogenesis. Previous studies have reported that cytosolic mtDNA stress can lead to cardiomyocytes pyroptosis, which is characterized by inflammasome formation. In this study, we attempted to investigate the mechanism of TFAM regulate cardiomyocytes pyroptosis induced by ionizing radiation.

MATERIALS/METHODS

The peripheral blood serum of patients with esophageal cancer before and after definitive chemoradiotherapy was collected for Luminex multiplex cytokine assays. C57BL/6 mice were irradiated with the whole heart using small animal radiation research platform (SARRP) to construct a radiation-induced myocardial damage (RIMD) mouse model, and the ventricular function was evaluated using 9.4T Bruker magnetic resonance (MR) scanner. The function changes of cardiomyocytes exposed to radiation were observed in vitro and in vivo after knocking out GSDMD. Furthermore, the changes of mitochondrial function, the levels of cytosolic mtDNA, and the protein levels of NF-kB and pyroptosis pathway in irradiated cardiomyocytes were analyzed by knockdown and overexpression of TFAM in vitro and in vivo.

RESULTS

By multifactor cytokine assays we found that pyroptosis related IL-1β and IL-18 were significantly increased in patients with high mean heart dose (MHD) after radiotherapy, while those with low MHD were not significantly increased after radiotherapy. Next, we successfully constructed the RIMD mouse model using a single heart irradiation of 20 Gy. We found that the gene expression of pyroptosis pathway was significantly up-regulated after cardiac irradiation by myocardial tissue transcriptomic sequencing. Compared with wild-type (WT) mice, cardiac systolic function of Gsdmd-/- mice was significantly improved at 1, 2, 6, 12, and 24 weeks after heart irradiation. In vitro, we also demonstrated increased viability of irradiated cardiomyocytes by knocking out GSDMD. In vitro and in vivo experiments confirmed the expression of TFAM decreased after radiation. By overexpression of TFAM, we found that irradiated cardiomyocytes showed improved mitochondrial function, decreased release of mtDNA into cytoplasm through mitochondrial permeability transition pores (mPTPs), decreased binding of cytosolic mtDNA to TLR9, and decreased expression of NF-kB and pyroptosis pathway proteins. Dual luciferase gene reporter assays and Chromatin immunoprecipitation (CHIP) assay confirmed that p65 could bind the NLRP3 promoter region. In addition, we found that ventricular function deteriorated and improved in mice with knockdown and overexpression of TFAM through adeno-associated virus serotype 9 (AAV9), respectively.

CONCLUSION

Our study indicated that TFAM regulate irradiated cardiomyocytes pyroptosis through mtDNA/TLR9/NF-kB pathway. We provide a novel mechanism of RIMD, revealing an underappreciated intervention target for RIMD.

Carm1 Inhibition Potentiates Irradiation-Induced Antitumor Immunity via Tumor Intrinsic STING Pathway Activation

PURPOSE/OBJECTIVE(S)

Radiotherapy is commonly applied in multiple cancer types. Besides irradiation induced direct cell death, radiotherapy stimulated significant immune responses for tumor control. Intact and functional cGAS-STING pathway in both tumor cells and host cells is indispensable for efficient irradiation-induced anti-tumor effects. Coactivator-associated arginine methyltransferase 1 (Carm1) is emerging as an attractive therapeutic target and a biomarker for prognosis in various types of cancer. It has been reported that Carm1 inhibition could improve immunotherapy induced anti-tumor effects. However, it remains unclear how tumor cell intrinsic Carm1 affects irradiation-induced anti-tumor immunity.

MATERIALS/METHODS

Carm1 deficient cell lines were established in MC38 and B16F10 murine cancer cells using the CRISPR/Cas9 technology. To verify the effects of tumor `subcutaneous tumor mouse models were established and one fraction of 15Gy was administrated when the tumor volume reached 200mm3, followed by flow cytometry assays. Transcriptome sequencing, protein mass spectrometry, single-cell sequencing, Digital Spatial Profiling (DSP), real-time qPCR, western blotting, immunofluorescence and co-immunoprecipitation were carried out to explore and verify possible molecular mechanisms.

RESULTS

Here we found Carm1 deficiency in tumor cells dramatically enhanced irradiation-induced anti-tumor immune responses. Transcriptome sequencing of irradiated tumor cells and further experiments then validated that cGAS-STING pathway was significantly activated after irradiation in the absence of Carm1 in tumor cells, which contributed to enhance anti-tumor immunity after irradiation. Mechanistically, Carm1 deficiency in tumor cells attenuated autophagy, resulting in increased cytoplasmic mtDNA enrichment and enhanced cGAS-STING pathway activation. On the other hand, we also found that Carm1 caused asymmetric arginine methylation (ADMA) modification of TBK1 with reduced phosphorylation level, and Carm1 deficiency could activate cGAS-STING pathway by reducing AMDA modification and enhancing phosphorylation of TBK1. Finally, Carm1 inhibitor EZM2302 was applied in combination with radiotherapy in vitro, and it's indicated that combination therapy resulted in intensive anti-tumor immunity and prominent abscopal effects.

CONCLUSION

In this study, we identified that Carm1 ablation in tumor cells could promote irradiation-induced antitumor immunity through tumor cell intrinsic STING pathway activation. Mechanically, Carm1 deficiency directly activated the cGAS-STING pathway by interacting with TBK1 and increased mtDNA accumulation in cytoplasm by inhibiting autophagy. These findings provided new strategies for targeting Carm1 to boost the efficacy of radiotherapy.

RUNX1 as a Potential Target for Combined Radioimmunotherapy of Lung Adenocarcinoma

PURPOSE/OBJECTIVE(S)

Radioimmunotherapy for non-small cell lung cancer has good clinical application prospects. The role and mechanism of RUNX1 in DNA damage repair were explored for its potential role in lung adenocarcinoma radioimmunotherapy.

MATERIALS/METHODS

To study the effect of RUNX1 expression level on the expression of DNA damage repair system related factors and radiation sensitivity of lung adenocarcinoma cells. As an important nuclear transcription factor, RUNX1 was explored whether directly regulating the expression of Nrf2, Rad51, BRCA1, and verifying their respective DNA binding sites in the promoter region through relevant databases. To observe the effect of RUNX1 knockout and overexpression on the expression level of PD-L1 in tumor cells at the cell level; The effect of RUNX1 expression level on the sorting and presentation of PD-L1 cells was investigated by the method of nucleocytoplasmic separation. According to literature reports, CMTM6 and ALIX play a key role in the process of PD-L1 cell sorting and presentation, and explore whether RUNX1 plays a role through this factor. The effect of phosphorylation level of different splicing bodies of RUNX1 (RUNX1a/b/c) on the expression level and DNA damage repair system related factors on tumor radiosensitivity were also explored.

RESULTS

According to TCGA database, RUNX1 is highly expressed and phosphorylated in lung adenocarcinoma. Through gene comparison with the database, it was found that RUNX1 binding sites existed in the promoter region of several factors related to this study, including ALIX, Nrf2, BRCA1, RAD51, ATM, H2AX, etc. After being activated by MAPKp38 phosphorylation, RUNX1a can positively regulate Nrf2 signal pathway. The expression of RUNX1 and p-RUNX1 is time-dependent on ionizing radiation. At the same time, it was found that the expression of RUNX1 and p-RUNX1 was dose-dependent on ionizing radiation, and the expression trend of Nrf2 signal pathway related factors was consistent with RUNX1. RUNX1 regulates the expression of PD-L1, BRCA1, ALIX and Nrf2. Bioinformatics analysis and flow cytometry data show that RUNX1 has inhibitory effect on tumor microenvironment of lung adenocarcinoma.

CONCLUSION

RUNX1 regulates DNA damage repair system and has inhibitory effect on tumor immunity. Inhibiting the expression of RUNX1 in lung adenocarcinoma cells can enhance the effect of radioimmunotherapy.

Intraoral Gavage of Second-Generation Probiotic Lactobacillus Reuteri Releasing IFN-β (LR-IFN-β) Mitigates Intestinal Irradiation Toxicity and Improves Survival During Whole Abdomen Irradiation (WAI)

PURPOSE/OBJECTIVE(S)

We sought to establish a method by which to overcome the toxicity of WAI to facilitate clinical application in Ovarian Cancer patients.

MATERIALS/METHODS

We irradiated C57BL/6J mice to 19.75 Gy WAI and assessed the primary endpoint of overall survival (OS). In a separate experiment, mice were irradiated to 12 Gy WAI and intestinal barrier integrity was compared between groups: control (0 Gy), irradiation only, 12 Gy + LR, 12 Gy + IFN-β, and 12 Gy + LR-IFN-β. Luminex assay of plasma and intestinal cells were also assayed at day 5 after WAI for radiation-induced inflammatory cytokines, and fecal matter was analyzed for LR-IFN-β clearance and levels of the LR-derived IFN-β gene from day 1 to 5 in control non-irradiated mice. Moreover, fluorescent beads were intraorally administered three hours prior to sacrifice at days 2 or 5 after WAI, and blood was assayed for beads.

RESULTS

Mice receiving LR-IFN-β (109 bacteria in 100 mL of saline) 24-hours following a single fraction of 19.75 Gy WAI showed improved OS compared to control irradiated mice (p = 0.03). LR-IFN-β gavage maintained intestinal barrier integrity (p < 0.05) by stimulating intestinal stem cells regenerations (improved levels of Lgr5+ cells, occludin, and I-CAM; p < 0.05), and reduced levels of intestinal pro-inflammatory cytokines, including IFN-γ (p = 0.0261), IL-3 (p < 0.0020) and IL-17 (p < 0.0070). There was no significant effect of control LR or intraperitoneal injection of IFN-β protein at 24 hours after WAI. Detectable levels of LR-IFN-β bacteria were also cleared from fecal matter by day three via colony assay and rt-PCR, with no detectable growth of LR-IFN-β in blood from gavaged irradiated mice (13.5 Gy WAI).

CONCLUSION

LR-IFN-β is both a feasible and effective radiation mitigator that could potentially improve the management of ovarian cancer patients. Furthermore, the subsequent addition of platinum/taxane-based chemotherapy to the combination of WAI and LR-IFN-β should reduce tumor volume while protecting the intestine and thus improve overall survival in ovarian cancer patients.

Safety and Efficacy Analysis of Patients with Extensive-Stage Small Cell Lung Cancer (ES-SCLC) Treated with SHR-1316 Plus Chemotherapy and Sequential Chest Radiotherapy as First-Line Therapy from a Phase II Trial

PURPOSE/OBJECTIVE(S)

CAPSTONE-1, a phase 3 trial, showed that SHR-1316 (PD-L1 antibody) combined with standard first-line chemotherapy could prolong overall survival (OS) in patients (pts) with ES-SCLC. The CREST trial reported consolidative thoracic radiotherapy (TRT) of 30 Gy in 10 fractions provided a 10% 2-year OS benefit and more intensive TRT should be investigated in ES-SCLC. In the era of immunotherapy, the role of TRT also needs further exploration. Therefore, we designed this clinical trial to investigate the efficacy and safety of SHR-1316 plus first-line chemotherapy followed by TRT combined with SHR-1316.

MATERIALS/METHODS

Key inclusion criteria were pts aged 18-75 years, with previously untreated histologically or cytologically confirmed ES-SCLC, and an ECOG performance status of 0-1. Eligible pts would receive 4∼6 cycles of SHR-1316 (20mg/kg, D1, q3w) combined with EP/EC (etoposide, 100mg/m2, D1-5, q3w and cisplatin, 75mg/m², D1-3, q3w or carboplatin, AUC = 5, D1, q3w), followed by SHR-1316 combined with TRT (≥3 Gy*10 f or ≥2 Gy*25 f, involved-field irradiation), and then the maintenance therapy with SHR-1316 until disease progression or intolerable adverse events (AEs). The main endpoints included ORR, PFS and safety.

RESULTS

From October 2020 to January 2023, 33 pts received SHR-1316 and sequential consolidative TRT. Among them, 19 pts received high-dose TRT (>3 Gy*10 f or ≥2 Gy*25 f) and 14 pts received low-dose TRT (≤3 Gy*10 f or<2 Gy*25 f). The median age was 62 (range: 38-73). Most pts were male (28, 84.8%), former smokers (22, 66.7%) with an ECOG performance status 1 (32, 97%). Ten (30.3%) pts were diagnosed with brain metastasis and 10 (30.3%) pts had liver metastasis at baseline. At the data cutoff date, 9 pts remained on treatment, the average number of treatment cycles was 9.2. 33 pts had at least one 1 post-treatment tumor assessment. The confirmed ORR and DCR were 90.9% (30/33) and 100% (33/33) in all pts, were 89.5% (17/19) and 100% (19/19) in high-dose TRT group, and were 92.9% (13/14) and 100% (14/14) in low-dose TRT group. The median PFS was 10.2(CI: 5.8∼14.7) months in all pts, was 7 (CI: 3.8∼10.2) months in high-dose TRT group and 10.4 (CI: 8.4∼12.3) months in low-dose TRT group. AEs occurred in 27 (81.8%) pts and grade 3 or 4 AEs occurred in 20 (60.6%) pts. The most common grade 3 or 4 AEs included neutropenia (15, 45.5%), leukopenia (8, 24.2%), lymphocytopenia (5, 15.2%), pneumonia (3, 9.1%), anemia (3, 9.1%) and thrombocytopenia (2, 6.1%).

CONCLUSION

SHR-1316 plus chemotherapy and sequential TRT as first-line therapy for ES-SCLC showed promising efficacy and acceptable safety. There is no significant difference between high-dose and low-dose TRT groups in terms of safety and efficacy according to current data.

HPK1 Inhibition Enhancing HFRT Anti-Tumor Immune Response

PURPOSE/OBJECTIVE(S)

Radiation therapy, as one of the canonical treatments for classic tumors, results in impressive clinical responses. Stereotactic body radiotherapy (SBRT) has been increasingly used as one main therapy in early-stage non-small-cell lung cancer (NSCLC). SBRT affords good local tumor control, however, recurrence and metastasis are still the main causes of treatment failure. With the continuous deepening of the relationship between radiotherapy (RT) and immunity, reversing RT induced immunosuppression is considered to be a promising strategy to improve radiotherapy efficacy. Hematopoietic progenitor kinase 1 (HPK1) is mainly expressed in immune cells while rarely expressed in tumor cells. It has been proven to play a negative regulatory role in T cell receptor (TCR) signal. Therefore, we hypothesized that the combination of HPK1 inhibitor with SBRT would boost local and systemic anti-tumor immune responses by potentiating the anti-tumor effects of SBRT.

MATERIALS/METHODS

Using Digital Spatial Profiler (DSP), we analyzed HPK1 expression in the tumor specimens of 39 NSCLC patients treated with SBRT. By establishing mice subcutaneous tumor models, we assessed the combination of a HPK1 inhibitor and local hyper-fractionated radiotherapy (HFRT) on local and systemic tumor control and mouse survival. Using Single-cell RNA sequencing, Flow cytometry and pharmacological treatment, we analyzed and verified Tumor-infiltrating lymphocytes (TILs), and excavated the specific mechanism of the HPK1 inhibitor enhancing HFRT -induced anti -tumor immune response.

RESULTS

In the tumor specimens of NSCLC patients treated with SBRT, we found that high expression HPK1 in TILs predicted poor progression-free survival (PFS). Among the C57BL/6 mice model, HFRT combined with a HPK1 inhibitor promoted local response, and improved the survival rate of mice, showing better anti-tumor curative effects. We further showed that HFRT promoted CD8+ T cell cytotoxic activity, and also aggravated CD8+ T cell exhaustion. After the intervention of HPK1 small molecular inhibitors, the proportion of exhaustion CD8+T cells was significantly reduced, while CD8+T cell cytotoxic activity was further enhanced in the later period. Single-cell RNA sequencing and pharmacological inhibition of HPK1 revealed that HPK1 mediated the exhaustion of CD8+T cells by regulating RGS16. In abscopal effects preclinical models, BGB-15025 induced obvious abscopal effect.

CONCLUSION

Thus, we demonstrate that HPK1 mediates HFRT-induced CD8+T cell exhaustion by regulating RGS16, and HPK1 is an attractive drug target for enhancing local and systemic radiotherapy.

Using MRI Radiomics to Predict the Efficacy of Immunotherapy for Brain Metastasis in Patients with Non-small Cell Lung Cancer

PURPOSE/OBJECTIVE(S)

Despite immune checkpoint inhibitors (ICIs) has been proven effective in patients with advanced NSCLC, controversial therapeutic responses are seen in brain metastatic lesions. There are no robust biomarkers that predict benefit from this regimen. We evaluated the utility of novel imaging biomarkers (radiomics) to distinguish NSCLC patients with brain metastases (BMs) who will benefit from ICIs from those likely to progress despite therapy.

MATERIALS/METHODS

One-hundred and seventy-four NSCLC Patients with BMs treated with ICIs from June 2019 - June 2022 were identified. We collected patient clinical outcomes and pre-treatment MRI images. Images were split into training and test sets. Brain metastatic lesions were contoured on ITK-SNAP software and 3748 radiomic features capturing both intra- and peritumoral texture patterns were extracted. The primary endpoint of this study was intracranial progression-free survival (iPFS) and the secondary objective were progression-free survival (PFS) and overall survival (OS). We used the least absolute shrinkage and selection operator (LASSO) Cox regression model to build the radiomic signature for ORR. Based on the support vector machine (SVM) model, we construct the Clinical-radiomics nomogram (CRN). Multivariable Cox regression analysis were performed to evaluate the effect of each factor on iPFS. We performed Kaplan-Meier survival analysis and log-rank tests to assess prognostic value of the features.

RESULTS

We identified 174 patients who fit our criteria with available MRI images. 122 patients treated in our center were divided into a training set and 52 patients treated in another center were divided into a test set. The intratumoral radiomic signatures(IRS), peritumoral radiomic signatures(PRS) and CRN showed favorable predictive effects for ORR with the area under the receiver operating curve (AUC) of (IRS: 0.845 (95% CI: 0.776-0.914); PRS: 0.799 (95% CI:0.720-0.879); CRN:0.907 (95% CI: 0.855-0.959))in the training set and (IRS: 0.809 (95% CI: 0.693-0.926); PRS: 0.749 (95% CI:0.616-0.883); CRN:0.888(95% CI:0.798-0.979)) in the test set. Kaplan-Meier analyses showed a significantly longer iPFS in the high-CRN group versus the low-CRN group (P < 0.001). The CRNs were also found significantly associated with PFS (P < 0.001), but not OS.

CONCLUSION

Radiomic biomarkers from pre-treatment MRI images in NSCLC patients with BMs were predictive of iPFS to ICIs. Pre-treatment radiomics may allow early prediction of benefit and expedite more aggressive treatment for high-risk patients. Additional validation of these imaging biomarkers is warranted.