Beyond conventional bounds: Surpassing system limits for stereotactic ablative (SAbR) lung radiotherapy using CBCT-based adaptive planning system.

PURPOSE: Online adaptive radiotherapy relies on a high degree of automation to enable rapid planning procedures. The Varian Ethos intelligent optimization engine (IOE) was originally designed for conventional treatments so it is crucial to provide clear guidance for lung SAbR plans. This study investigates using the Ethos IOE together with adaptive-specific optimization tuning structures we designed and templated within Ethos to mitigate inter-planner variability in meeting RTOG metrics for both online-adaptive and offline SAbR plans. METHODS: We developed a planning strategy to automate the generation of tuning structures and optimization. This was validated by retrospective analysis of 35 lung SAbR cases (total 105 fractions) treated on Ethos. The effectiveness of our planning strategy was evaluated by comparing plan quality with-and-without auto-generated tuning structures. Internal target volume (ITV) contour was compared between that drawn from CT simulation and from cone-beam CT (CBCT) at time of treatment to verify CBCT image quality and treatment effectiveness. Planning strategy robustness for lung SAbR was quantified by frequency of plans meeting reference plan RTOG constraints. RESULTS: Our planning strategy creates a gradient within the ITV with maximum dose in the core and improves intermediate dose conformality on average by 2%. ITV size showed no significant difference between those contoured from CT simulation and first fraction, and also trended towards decreasing over course of treatment. Compared to non-adaptive plans, adaptive plans better meet reference plan goals (37% vs. 100% PTV coverage compliance, for scheduled and adapted plans) while improving plan quality (improved GI (gradient index) by 3.8%, CI (conformity index) by 1.7%). CONCLUSION: We developed a robust and readily shareable planning strategy for the treatment of adaptive lung SAbR on the Ethos system. We validated that automatic online plan re-optimization along with the formulated adaptive tuning structures can ensure consistent plan quality. With the proposed planning strategy, highly ablative treatments are feasible on Ethos.

Adapt-On-Demand: A Novel Strategy for Personalized Adaptive Radiation Therapy for Locally Advanced Lung Cancer.

PURPOSE: Real-time adaptation of thoracic radiation plans is compelling because offline adaptive experiences show that tumor volumes and lung anatomy can change during therapy. We present and analyze a novel adaptive-on-demand (AOD) workflow combining online adaptive radiation therapy (o-ART) on the ETHOS system with image guided radiation therapy delivery on a Halcyon unit for conventional fractionated radiation therapy of locally advanced lung cancer (LALC). METHODS AND MATERIALS: We analyzed 26 patients with LALC treated with the AOD workflow, adapting weekly. We timed segments of the workflow to evaluate efficiency in a real-world clinic. Target coverage and organ at risk (OAR) doses were compared between adaptive plans (ADP) and nonadaptive scheduled plans (SCH). Planning robustness was evaluated by the frequency of preplanning goals achieved in ADP plans, stratified by tumor volume change. RESULTS: The AOD workflow was achievable within 30 minutes for most radiation fractions. Over the course of therapy, we observed an average 26.6% ± 23.3% reduction in internal target volume (ITV). Despite these changes, with o-ART, ITV and planning target volume (PTV) coverage (V100%) was 99.2% and 93.9% for all members of the cohort, respectively. This represented a 2.9% and 6.8% improvement over nonadaptive plans (P < .05), respectively. For tumors that grew >10%, V100% was 93.1% for o-ART and 76.4% for nonadaptive plans, representing a median 17.2% improvement in the PTV coverage (P < .05). In these plans, critical OAR constraints were met 94.1% of the time, whereas in nonadaptive plans, this figure was 81.9%. This represented reductions of 1.32 Gy, 1.34 Gy, or 1.75 Gy in the heart, esophagus, and lung, respectively. The effect was larger when tumors had shrunk more than 10%. Regardless of tumor volume alterations, the PTV/ITV coverage was achieved for all adaptive plans. Exceptional cases, where dose constraints were not met, were due to large initial tumor volumes or tumor growth. CONCLUSIONS: The AOD workflow is efficient and robust in responding to anatomic changes in LALC patients, providing dosimetric advantages over standard therapy. Weekly adaptation was adequate to keep pace with changes. This approach is a feasible alternative to conventional offline replanning workflows for managing anatomy changes in LALC radiation therapy.

Dynamic ultrasound molecular-targeted imaging of senescence in evaluation of lapatinib resistance in HER2-positive breast cancer.

BACKGROUND: Prolonged treatment of HER2+ breast cancer with lapatinib (LAP) causes cellular senescence and acquired drug resistance, which often associating with poor prognosis for patients. We aim to explore the correlation between cellular senescence and LAP resistance in HER2+ breast cancer, screen for molecular marker of reversible senescence, and construct targeted nanobubbles for ultrasound molecular imaging to dynamically evaluate LAP resistance. METHODS AND RESULTS: In this study, we established a new cellular model of reversible cellular senescence using LAP and HER2+ breast cancer cells and found that reversible senescence contributed to LAP resistance in HER2+ breast cancer. Then, we identified ecto-5'-nucleotidase (NT5E) as a marker of reversible senescence in HER2+ breast cancer. Based on this, we constructed NT5E-targeted nanobubbles (NT5E-FITC-NBs) as a new molecular imaging modality which could both target reversible senescent cells and be used for ultrasound imaging. NT5E-FITC-NBs showed excellent physical and imaging characteristics. As an ultrasound contrast agent, NT5E-FITC-NBs could accurately identify reversible senescent cells both in vitro and in vivo. CONCLUSIONS: Our data demonstrate that cellular senescence-based ultrasound-targeted imaging can identify reversible senescence and evaluate LAP resistance effectively in HER2+ breast cancer cells, which has the potential to improve cancer treatment outcomes by altering therapeutic strategies ahead of aggressive recurrences.

GLUT3 promotes macrophage signaling and function via RAS-mediated endocytosis in atopic dermatitis and wound healing.

The facilitative GLUT1 and GLUT3 hexose transporters are expressed abundantly in macrophages, but whether they have distinct functions remains unclear. We confirmed that GLUT1 expression increased after M1 polarization stimuli and found that GLUT3 expression increased after M2 stimulation in macrophages. Conditional deletion of Glut3 (LysM-Cre Glut3fl/fl) impaired M2 polarization of bone marrow-derived macrophages. Alternatively activated macrophages from the skin of patients with atopic dermatitis showed increased GLUT3 expression, and a calcipotriol-induced model of atopic dermatitis was rescued in LysM-Cre Glut3fl/fl mice. M2-like macrophages expressed GLUT3 in human wound tissues as assessed by transcriptomics and costaining, and GLUT3 expression was significantly decreased in nonhealing, compared with healing, diabetic foot ulcers. In an excisional wound healing model, LysM-Cre Glut3fl/fl mice showed significantly impaired M2 macrophage polarization and delayed wound healing. GLUT3 promoted IL-4/STAT6 signaling, independently of its glucose transport activity. Unlike plasma membrane-localized GLUT1, GLUT3 was localized primarily to endosomes and was required for the efficient endocytosis of IL-4Rα subunits. GLUT3 interacted directly with GTP-bound RAS in vitro and in vivo through its intracytoplasmic loop domain, and this interaction was required for efficient STAT6 activation and M2 polarization. PAK activation and macropinocytosis were also impaired without GLUT3, suggesting broader roles for GLUT3 in the regulation of endocytosis. Thus, GLUT3 is required for efficient alternative macrophage polarization and function, through a glucose transport-independent, RAS-mediated role in the regulation of endocytosis and IL-4/STAT6 activation.

Development of a Covalent Inhibitor of c-Jun N-Terminal Protein Kinase (JNK) 2/3 with Selectivity over JNK1.

The c-Jun N-terminal kinases (JNKs) are members of the mitogen-activated protein kinase (MAPK) family, which includes JNK1-JNK3. Interestingly, JNK1 and JNK2 show opposing functions, with JNK2 activity favoring cell survival and JNK1 stimulating apoptosis. Isoform-selective small molecule inhibitors of JNK1 or JNK2 would be useful as pharmacological probes but have been difficult to develop due to the similarity of their ATP binding pockets. Here, we describe the discovery of a covalent inhibitor YL5084, the first such inhibitor that displays selectivity for JNK2 over JNK1. We demonstrated that YL5084 forms a covalent bond with Cys116 of JNK2, exhibits a 20-fold higher Kinact/KI compared to that of JNK1, and engages JNK2 in cells. However, YL5084 exhibited JNK2-independent antiproliferative effects in multiple myeloma cells, suggesting the existence of additional targets relevant in this context. Thus, although not fully optimized, YL5084 represents a useful chemical starting point for the future development of JNK2-selective chemical probes.

LIMS-Kinase provides sensitive and generalizable label-free in vitro measurement of kinase activity using mass spectrometry.

Measurements of kinase activity are important for kinase-directed drug development, analysis of inhibitor structure and function, and understanding mechanisms of drug resistance. Sensitive, accurate, and miniaturized assay methods are crucial for these investigations. Here, we describe a label-free, high-throughput mass spectrometry-based assay for studying individual kinase enzymology and drug discovery in a purified system, with a focus on validated drug targets as benchmarks. We demonstrate that this approach can be adapted to many known kinase substrates and highlight the benefits of using mass spectrometry to measure kinase activity in vitro, including increased sensitivity. We speculate that this approach to measuring kinase activity will be generally applicable across most of the kinome, enabling research on understudied kinases and kinase drug discovery.

T Stage and Pretreatment Standardized Uptake Values Predict Tumor Recurrence With 5-Fraction SABR in Early-Stage Non-Small Cell Lung Cancer.

Purpose: Five-fraction stereotactic ablative radiotherapy (SABR) regimens are frequently used to treat centrally located early-stage non-small cell lung cancer or disease in the proximity of the chest wall as a means of optimizing tumor control and reducing treatment toxicity. However, increasing these SABR regimens to 5 fractions may reduce tumor control outcomes. We sought to identify the clinical parameters predictive of treatment failures with these 5-fraction courses. Methods: Ninety patients with T1-2 non-small cell lung cancer were treated with 50 or 60 Gy in 5 fractions. Failure over time was modeled using cumulative incidences of local, regional, or distant failure, with death as a competing risk. Cox proportional hazards analysis for incidences of failure was performed to control for patient variables. Results: Of 90 patients, 24 of 53 patients with T1 tumors and 19 of 37 patients with T2 tumors received 50 Gy SABR, and the other 47 patients received 60 Gy. Two-year overall survival and progression-free survival for the whole cohort were 75.8% and 59.3%, respectively. Total SABR dose (50 vs 60 Gy) did not influence survival nor failure rates at 2 and 5 years. Within 2 years of treatment, 7.8% of all patients developed local failure. For all patient and tumor characteristics evaluated, only T stage and pretreatment positron emission tomography standardized uptake values served as predictors of local, regional, and distant failure at 2 and 5 years posttreatment on univariate and multivariable analysis. Conclusions: Five-fraction SABR provides excellent in-field control. T2 and high fluorodeoxyglucose uptake tumors have increased failure rates, suggesting the potential need for adjuvant therapies, which are being assessed in randomized phase 3 trials.

Case Report: Resolution of radiation pneumonitis with androgens and growth hormone.

Radiation pneumonitis (RP) occurs in some patients treated with thoracic radiation therapy. RP often self-resolves, but when severe it is most commonly treated with corticosteroids because of their anti-inflammatory properties. Androgens and human growth hormone (HGH) also have anti-inflammatory and healing properties in the lung, but have not been studied as a remedy for RP. Here we present a case of corticosteroid-refractory RP that resolved with androgen and HGH-based therapy. Case Presentation: A 62 year old male body builder with excellent performance status presented with locally advanced non-small cell lung cancer characterized by a 7 cm mass in the right lower lobe and associated right hilar and subcarinal lymph node involvement. He was treated with chemoradiation and an excellent tumor response was observed. However, 2 months post-treatment he developed severe shortness of breath and imaging was consistent with RP. His RP was refractory to prednisone and antibiotic therapy, despite various regimens over a 9 month period. The patient self-treated with an androgen and HGH-based regimen and the RP promptly resolved. Conclusion: The anti-inflammatory properties of androgens and HGH have prompted an exploration of their potential role in therapeutic strategies to treat pro-inflammatory conditions such as sepsis, infections and interstitial lung disease. This case study suggests a potential role for the use of androgens for the treatment of steroid-refractory RP after radiation therapy. However, the applicability of this strategy to general populations should be weighed carefully against secondary effects of these agents, especially in the setting of cancer survivorship.

Thermal Shift Assay for Small GTPase Stability Screening: Evaluation and Suitability.

Thermal unfolding methods are commonly used as a predictive technique by tracking the protein's physical properties. Inherent protein thermal stability and unfolding profiles of biotherapeutics can help to screen or study potential drugs and to find stabilizing or destabilizing conditions. Differential scanning calorimetry (DSC) is a 'Gold Standard' for thermal stability assays (TSA), but there are also a multitude of other methodologies, such as differential scanning fluorimetry (DSF). The use of an external probe increases the assay throughput, making it more suitable for screening studies, but the current methodologies suffer from relatively low sensitivity. While DSF is an effective tool for screening, interpretation and comparison of the results is often complicated. To overcome these challenges, we compared three thermal stability probes in small GTPase stability studies: SYPRO Orange, 8-anilino-1-naphthalenesulfonic acid (ANS), and the Protein-Probe. We studied mainly KRAS, as a proof of principle to obtain biochemical knowledge through TSA profiles. We showed that the Protein-Probe can work at lower concentration than the other dyes, and its sensitivity enables effective studies with non-covalent and covalent drugs at the nanomolar level. Using examples, we describe the parameters, which must be taken into account when characterizing the effect of drug candidates, of both small molecules and Designed Ankyrin Repeat Proteins.

NCCN Guidelines® Insights: Lung Cancer Screening, Version 1.2022.

The NCCN Guidelines for Lung Cancer Screening recommend criteria for selecting individuals for screening and provide recommendations for evaluation and follow-up of lung nodules found during initial and subsequent screening. These NCCN Guidelines Insights focus on recent updates to the NCCN Guidelines for Lung Cancer Screening.

Therapeutic Targeting the Allosteric Cysteinome of RAS and Kinase Families.

Allosteric mechanisms are pervasive in nature, but human-designed allosteric perturbagens are rare. The history of KRASG12C inhibitor development suggests that covalent chemistry may be a key to expanding the armamentarium of allosteric inhibitors. In that effort, irreversible targeting of a cysteine converted a non-deal allosteric binding pocket and low affinity ligands into a tractable drugging strategy. Here we examine the feasibility of expanding this approach to other allosteric pockets of RAS and kinase family members, given that both protein families are regulators of vital cellular processes that are often dysregulated in cancer and other human diseases. Moreover, these heavily studied families are the subject of numerous drug development campaigns that have resulted, sometimes serendipitously, in the discovery of allosteric inhibitors. We consequently conducted a comprehensive search for cysteines, a commonly targeted amino acid for covalent drugs, using AlphaFold-generated structures of those families. This new analysis presents potential opportunities for allosteric targeting of validated and understudied drug targets, with an emphasis on cancer therapy.

Synthesis and Structure-Activity relationships of cyclin-dependent kinase 11 inhibitors based on a diaminothiazole scaffold.

Cyclin-dependent kinases (CDK) are attractive targets for drug discovery due to their wide range of cellular functions. CDK11 is an understudied CDK with roles in transcription and splicing, cell cycle regulation, neuronal function, and apoptosis. In this study, we describe a medicinal chemistry campaign to identify a CDK11 inhibitor. Employing a promising but nonselective CDK11-targeting scaffold (JWD-047), extensive structure-guided medicinal chemistry modifications led to the identification of ZNL-05-044. A combination of biochemical evaluations and NanoBRET cellular assays for target engagement guided the SAR towards a 2,4-diaminothiazoles CDK11 probe with significantly improved kinome-wide selectivity over JWD-047. CDK11 inhibition with ZNL-05-044 leads to G2/M cell cycle arrest, consistent with prior work evaluating OTS964, and impacts CDK11-dependent mRNA splicing in cells. Together, ZNL-05-044 serves as a tool compound for further optimization and interrogation of the consequences of CDK11 inhibition.

ADAP1 promotes latent HIV-1 reactivation by selectively tuning KRAS-ERK-AP-1 T cell signaling-transcriptional axis.

Immune stimulation fuels cell signaling-transcriptional programs inducing biological responses to eliminate virus-infected cells. Yet, retroviruses that integrate into host cell chromatin, such as HIV-1, co-opt these programs to switch between latent and reactivated states; however, the regulatory mechanisms are still unfolding. Here, we implemented a functional screen leveraging HIV-1's dependence on CD4+ T cell signaling-transcriptional programs and discovered ADAP1 is an undescribed modulator of HIV-1 proviral fate. Specifically, we report ADAP1 (ArfGAP with dual PH domain-containing protein 1), a previously thought neuronal-restricted factor, is an amplifier of select T cell signaling programs. Using complementary biochemical and cellular assays, we demonstrate ADAP1 inducibly interacts with the immune signalosome to directly stimulate KRAS GTPase activity thereby augmenting T cell signaling through targeted activation of the ERK-AP-1 axis. Single cell transcriptomics analysis revealed loss of ADAP1 function blunts gene programs upon T cell stimulation consequently dampening latent HIV-1 reactivation. Our combined experimental approach defines ADAP1 as an unexpected tuner of T cell programs facilitating HIV-1 latency escape.

Acid-Catalyzed Synthesis of Isatoic Anhydride-8-Secondary Amides Enables IASA Transformations for Medicinal Chemistry.

Quinazolin-dione-N-3-alklyl derivatives are the core scaffolds for several categories of bioactive small molecules, but current synthetic methods are costly, involve environmental hazards, and are not uniformly scalable. Here, we report an inexpensive, flexible, and scalable method for the one-pot synthesis of substituted quinazolin-dione-N-3-alkyls (isomers of isatoic-8-secondary amides (IASAs)) from isatin that take advantage of in situ capture of imidic acid under acidic conditions. We further show that this method can be used for the synthesis of a wide variety of derivatives with medicinal uses.

PD-L1P146R is prognostic and a negative predictor of response to immunotherapy in gastric cancer.

Cancer cells evade immune detection via programmed cell death 1/programmed cell death-ligand 1 (PD-1/PD-L1) interactions that inactivate T cells. PD-1/PD-L1 blockade has become an important therapy in the anti-cancer armamentarium. However, some patients do not benefit from PD-1/PD-L1 blockade despite expressing PD-L1. Here, we screened 101 gastric cancer (GC) patients at diagnosis and 141 healthy control subjects and reported one such subpopulation of GC patients with rs17718883 polymorphism in PD-L1, resulting in a nonsense P146R mutation. We detected rs17718883 in 44% of healthy control subjects, and rs17718883 was associated with a low susceptibility to GC and better prognosis in GC patients. Structural analysis suggests that the mutation weakens the PD-1:PD-L1 interaction. This was supported by co-culture experiments of T cells, with GC cells showing that the P146R substitution results in interferon (IFN)-γ secretion by T cells and enables T cells to suppress GC cell growth. Similar results with animal gastric tumor models were obtained in vivo. PD-1 monoclonal antibody treatment did not enhance the inhibitory effect of T cells on GC cells expressing PD-L1P146Rin vitro or in vivo. This study suggests that rs17718883 is common and may be used as a biomarker for exclusion from PD-1/PD-L1 blockade therapy.

A structural model of a Ras-Raf signalosome.

The protein K-Ras functions as a molecular switch in signaling pathways regulating cell growth. In the human mitogen-activated protein kinase (MAPK) pathway, which is implicated in many cancers, multiple K-Ras proteins are thought to assemble at the cell membrane with Ras effector proteins from the Raf family. Here we propose an atomistic structural model for such an assembly. Our starting point was an asymmetric guanosine triphosphate-mediated K-Ras dimer model, which we generated using unbiased molecular dynamics simulations and verified with mutagenesis experiments. Adding further K-Ras monomers in a head-to-tail fashion led to a compact helical assembly, a model we validated using electron microscopy and cell-based experiments. This assembly stabilizes K-Ras in its active state and presents composite interfaces to facilitate Raf binding. Guided by existing experimental data, we then positioned C-Raf, the downstream kinase MEK1 and accessory proteins (Galectin-3 and 14-3-3σ) on and around the helical assembly. The resulting Ras-Raf signalosome model offers an explanation for a large body of data on MAPK signaling.

Accelerated Hypofractionated Image-Guided vs Conventional Radiotherapy for Patients With Stage II/III Non-Small Cell Lung Cancer and Poor Performance Status: A Randomized Clinical Trial.

IMPORTANCE: A significant subset of patients with stage II/III non-small cell lung cancer (NSCLC) cannot receive standard concurrent chemoradiotherapy owing to the risk of toxic effects outweighing potential benefits. Without concurrent chemotherapy, however, the efficacy of conventional radiotherapy is reduced. OBJECTIVE: To determine whether hypofractionated image-guided radiotherapy (IGRT) would improve overall survival in patients with stage II/III NSCLC who could not receive concurrent chemoradiotherapy and therefore were traditionally relegated to receiving only conventionally fractionated radiotherapy (CFRT). DESIGN, SETTING, AND PARTICIPANTS: This nonblinded, phase 3 randomized clinical study enrolled 103 patients and analyzed 96 patients with stage II/III NSCLC and Zubrod performance status of at least 2, with greater than 10% weight loss in the previous 6 months, and/or who were ineligible for concurrent chemoradiotherapy after oncology consultation. Enrollment occurred at multiple US institutions. Patients were enrolled from November 13, 2012, to August 28, 2018, with a median follow-up of 8.7 (3.6-19.9) months. Data were analyzed from September 14, 2018, to April 11, 2021. INTERVENTIONS: Eligible patients were randomized to hypofractionated IGRT (60 Gy in 15 fractions) vs CFRT (60 Gy in 30 fractions). MAIN OUTCOMES AND MEASURES: The primary end point was 1-year overall survival. RESULTS: A total of 103 patients (96 of whom were analyzed [63 men (65.6%); mean (SD) age, 71.0 (10.2) years (range, 50-90 years)]) were randomized to hypofractionated IGRT (n = 50) or CFRT (n = 46) when a planned interim analysis suggested futility in reaching the primary end point, and the study was closed to further accrual. There was no statistically significant difference between the treatment groups for 1-year overall survival (37.7% [95% CI, 24.2%-51.0%] for hypofractionated IGRT vs 44.6% [95% CI, 29.9%-58.3%] for CFRT; P = .29). There were also no significant differences in median overall survival, progression-free survival, time to local failure, time to distant metastasis, and toxic effects of grade 3 or greater between the 2 treatment groups. CONCLUSIONS AND RELEVANCE: This phase 3 randomized clinical trial found that hypofractionated IGRT (60 Gy in 15 fractions) was not superior to CFRT (60 Gy in 30 fractions) for patients with stage II/III NSCLC ineligible for concurrent chemoradiotherapy. Further studies are needed to verify equivalence between these radiotherapy regimens. Regardless, for well-selected patients with NSCLC (ie, peripheral primary tumors and limited mediastinal/hilar adenopathy), the convenience of hypofractionated radiotherapy regimens may offer an appropriate treatment option. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01459497.

Inhibiting the redox function of APE1 suppresses cervical cancer metastasis via disengagement of ZEB1 from E-cadherin in EMT.

BACKGROUND: Metastasis is a major challenge in cervical cancer treatment. Previous studies have shown that the dual functional protein apurinic/apyrimidinic endonuclease 1 (APE1) promotes tumor metastasis and is overexpressed in cervical cancer. However, the biological role and mechanism of APE1 in cervical cancer metastasis have rarely been studied. METHODS: We used gene set enrichment analysis (GSEA) to determine the APE1-related signaling pathways in cervical cancer. To investigate the role and mechanism of APE1 in cervical cancer metastasis and invasion, immunohistochemistry, immunofluorescence, western blotting, secondary structure prediction, coimmunoprecipitation, luciferase reporter, and electrophoretic mobility shift assays were performed. The inhibitory effects of the APE1 redox function inhibitor APX3330 on cervical cancer metastasis were evaluated using animal models. RESULTS: Clinical data showed that high expression of APE1 was associated with lymph node metastasis in cervical cancer patients. GSEA results showed that APE1 was associated with epithelial to mesenchymal transition (EMT) in cervical cancer. Ectopic expression of APE1 promoted EMT and invasion of cervical cancer cells, whereas inhibition of APE1 suppressed EMT and invasion of cervical cancer cells in a redox function-dependent manner. Notably, APE1 redox function inhibitor APX3330 treatment dramatically suppressed cervical cancer cell lymph node and distant metastasis in vivo. Furthermore, we found that APE1 enhanced the interaction between ZEB1 and the E-cadherin promoter by binding to ZEB1, thereby suppressing the expression of E-cadherin, a negative regulator of EMT. CONCLUSION: Our findings help to elucidate the role played by APE1 in cervical cancer metastasis and targeting APE1 redox function may be a novel strategy for inhibiting cervical cancer metastasis.