AptBCis1, An Aptamer-Cisplatin Conjugate, Is Effective in Lung Cancer Leptomeningeal Carcinomatosis.

Treatment of lung cancer leptomeningeal carcinomatosis (LM) remains challenging partly due to the biological nature of the blood-brain barrier (BBB). Cisplatin has limited effects on LM, and it is notorious for neurotoxicity. Aptamers are small oligonucleotides considered as antibody surrogates. Here we report a DNA therapeutics, AptBCis1. AptBCis1 is a cisplatin-conjugated, BBB-penetrating, and cancer-targeting DNA aptamer. Its backbone, AptB1, was identified via in vivo SELEX using lung cancer LM orthotopic mouse models. The AptB1 binds to EAAT2, Nucleolin, and YB-1 proteins. Treatment with AptBCis1 1 mg/kg (equivalent to cisplatin 0.35 mg/kg) showed superior tumor suppressive effects compared to cisplatin 2 mg/kg in mice with lung cancer LM diseases. The cerebrospinal fluid platinum concentration in the AptBCis1 group was 10% of that in the cisplatin group. The data suggested the translational potential of AptBCis1 in lung cancer with LM and in cancers in which platinum-based chemotherapy remains as the standard of care.

Analysis of Cancer Survival Associated With Immune Checkpoint Inhibitors After Statistical Adjustment: A Systematic Review and Meta-analyses.

Importance: Appropriate clinical decision-making relies on accurate data interpretation, which in turn relies on the use of suitable statistical models. Long tails and early crossover-2 features commonly observed in immune checkpoint inhibitor (ICI) survival curves-raise questions as to the suitability of Cox proportional hazards regression for ICI survival analysis. Cox proportional hazards-Taylor expansion adjustment for long-term survival data (Cox-TEL) adjustment may provide possible solutions in this setting. Objective: To estimate overall survival and progression-free survival benefits of ICI therapy vs chemotherapy using Cox-TEL adjustment. Data Sources: A PubMed search was performed for all cataloged publications through May 22, 2022. Study Selection: The search was restricted to randomized clinical trials with search terms for ICIs and lung cancer, melanoma, or urothelial carcinoma. The publications identified were further reviewed for inclusion. Data Extraction and Synthesis: Cox proportional hazards ratios (HRs) were transformed to Cox-TEL HRs for patients with short-term treatment response (ie, short-term survivor) (ST-HR) and difference in proportions for patients with long-term survival (LT-DP) by Cox-TEL. Meta-analyses were performed using a frequentist random-effects model. Main Outcomes and Measures: Outcomes of interest were pooled overall survival (primary outcome) and progression-free survival (secondary outcome) HRs, ST-HRs, and LT-DPs. Subgroup analyses stratified by cancer type also were performed. Results: A total of 1036 publications was identified. After 3 levels of review against inclusion criteria, 13 clinical trials (7 in non-small cell lung cancer, 3 in melanoma, and 3 in urothelial carcinoma) were selected for the meta-analysis. In the primary analysis, pooled findings were 0.75 (95% CI, 0.70-0.81) for HR, 0.86 (95% CI, 0.81-0.92) for ST-HR, and 0.08 (95% CI, 0.06-0.10) for LT-DP. In the secondary analysis, the pooled values for progression-free survival were 0.77 (95% CI, 0.64-0.91) for HR, 1.02 (95% CI, 0.84-1.24) for ST-HR, and 0.10 (95% CI, 0.06-0.14) for LT-DP. Conclusions and Relevance: This systematic review and meta-analysis of ICI clinical trial results noted consistently larger ST-HRs vs Cox HRs for ICI therapy, with an LT-DP of approximately 10%. These results suggest that Cox HRs may not provide a full picture of survival outcomes when the risk reduction from treatment is not constant, which may aid in the decision-making process of oncologists and patients.

Cox Proportional Hazard Ratios Overestimate Survival Benefit of Immune Checkpoint Inhibitors: Cox-TEL Adjustment and Meta-Analyses of Programmed Death-Ligand 1 Expression and Immune Checkpoint Inhibitor Survival Benefit.

INTRODUCTION: Survival benefit of immune checkpoint inhibitor (ICI) therapy in lung cancer is not fully understood. METHODS: PubMed-cataloged publications through February 14, 2022, were queried for randomized controlled trials of ICI in lung cancer, and identified publications were reviewed for inclusion. Reported Cox hazard ratios (HRs) for overall survival were transformed to Cox-TEL HR for ICI short-term survivors (ST-HR) and difference in proportions for patients with long-term survival (LT-DP). Meta-analyses were performed using a frequentist random-effect model. Outcomes of interest were pooled overall survival Cox HR, ST-HR, and LT-DP in NSCLC, stratified by programmed death-ligand 1 (PD-L1) level (primary outcome) and ICI treatment line (secondary). RESULTS: A total of nine publications representing eight clinical trials were selected for meta-analysis. Primary analysis yielded the following metrics for patients with PD-L1 expression less than 1%, more than or equal to 1%, and more than or equal to 50%, respectively: pooled Cox HR, 0.71 (95% confidence interval [CI]: 0.62-0.82), 0.74 (95% CI: 0.68-0.82), and 0.62 (95% CI: 0.54-0.70); pooled ST-HR, 0.91 (95% CI: 0.79-1.05), 0.88 (95% CI: 0.82-0.94), and 0.70 (95% CI: 0.60-0.83); and pooled LT-DP, 0.10 (95% CI: 0.00-0.20), 0.09 (95% CI: 0.06-0.12), and 0.11 (95% CI: 0.05-0.17). Results of secondary analysis revealed LT-DP of approximately 10% across treatment lines. CONCLUSIONS: This study reveals an approximately 10% long-term survival probability increment in ICI long-term survivors across PD-L1-positive subpopulations in both ICI treatment lines. Furthermore, ST-HR was consistently poorer than Cox HR. For patients with PD-L1 less than 1%, neither LT-DP nor ST-HR achieved statistical significance. The analysis provides greater insight into the treatment effect of ICI in published trials.

Associations of influenza vaccination with severity of immune-related adverse events in patients with advanced thoracic cancers on immune checkpoint inhibitors.

Background: Whether influenza vaccination (FV) is associated with the severity of immune-related adverse events (IRAEs) in patients with advanced thoracic cancer on immune checkpoint inhibitors (ICIs) is not fully understood. Methods: Patients enrolled in this retrospective cohort study were identified from the Vanderbilt BioVU database and their medical records were reviewed. Patients with advanced thoracic cancer who received FV within 3 months prior to or during their ICI treatment period were enrolled in the FV-positive cohort and those who did not were enrolled in the FV-negative cohort. The primary objective was to detect whether FV is associated with decreased IRAE severity. The secondary objectives were to evaluate whether FV is associated with a decreased risk for grade 3-5 IRAEs and better survival times. Multivariable ordinal logistic regression was used for the primary analysis. Results: A total of 142 and 105 patients were enrolled in the FV-positive and FV-negative cohorts, respectively. There was no statistically significant difference in patient demographics or cumulative incidences of IRAEs between the two cohorts. In the primary analysis, FV was inversely associated with the severity of IRAEs (OR 0.63; p=0.046). In the secondary analysis, FV was associated with a decreased risk for grade 3-5 IRAEs (OR 0.42; p=0.005). Multivariable Cox regression showed that FV was not associated with survival times. Conclusions: Our study showed that FV does not increase toxicity for patients with advanced thoracic cancer on ICIs and is associated with a decreased risk for grade 3-5 IRAEs. No statistically significant survival differences were found between patients with and without FV.

Development and Evaluation of a Method to Correct Misinterpretation of Clinical Trial Results With Long-term Survival.

IMPORTANCE: In immune checkpoint inhibitor (ICI) trials, long tails and crossovers in survival curves-which violate the proportional hazards (PH) assumption-are commonly observed, making cure or restricted mean survival time models preferable for analysis of ICI survival data. Cox PH analysis, however, still appears in major medical journals, leading to potential misinterpretation of clinical significance. OBJECTIVE: To convert inappropriate Cox hazard ratios (HRs) to appropriate PH cure model treatment-effect estimates (HR for short-term survivors and difference in proportions [DP] for long-term survivors) for more accurate interpretation of published ICI trials. DESIGN AND SETTING: This study uses the Taylor expansion technique to demonstrate the mathematical relationship between Cox PH and PH cure models for data with long-term survival, and based on this relationship, proposes the Cox-TEL (Cox PH-Taylor expansion adjustment for long-term survival data) adjustment method. The proposed Cox-TEL method requires only 2 inputs: the reported Cox HRs and Kaplan-Meier-estimated survival probabilities. RESULTS: Comprehensive simulations show the strength of the proposed method in terms of power, bias, and type I error rate; these results, which are close to PH cure model estimates, were further verified in a melanoma data set (N = 285; Cox HR = 0.71; 95% CI, 0.51-0.91; Cox-TEL HR = 0.83; 95% CI, 0.60-1.07; PH cure HR = 0.86; 95% CI, 0.61-1.11; Cox-TEL DP = 0.10; 95% CI, 0.01-0.23; PH cure DP = 0.10; 95% CI, 0.00-0.21). The magnitude of potential difference between reported and adjusted HRs using real-world ICI trial results is demonstrated. For example, in the CheckMate 067 trial (nivolumab/ipilimumab combination therapy vs ipilimumab), the Cox HR was 0.54 (95% CI, 0.44-0.67), and the Cox-TEL HR was 0.90 (95% CI, 0.73-1.11). CONCLUSIONS AND RELEVANCE: The findings of this study suggest the need to revisit published ICI survival data analysis to address potential misinterpretation. The Cox-TEL method not only is designed for this purpose, but also is user friendly and easy to implement using published clinical trial data and a freely available R software package.

PINK1-Mediated Inhibition of EGFR Dimerization and Activation Impedes EGFR-Driven Lung Tumorigenesis.

EGFR is established as a driver of lung cancer, yet the regulatory machinery underlying its oncogenic activity is not fully understood. PTEN-induced kinase 1 (PINK1) kinase is a key player in mitochondrial quality control, although its role in lung cancer and EGFR regulation is unclear. In this study, we show that PINK1 physically directly interacts with EGFR via the PINK1 C-terminal domain (PINK1-CTD) and the EGFR tyrosine kinase domain. This interaction constituted an endogenous steric hindrance to receptor dimerization and inhibited EGFR-mediated lung carcinogenesis. Depletion of PINK1 from lung cancer cells promoted EGFR dimerization, receptor activation, EGFR downstream signaling, and tumor growth. In contrast, overexpression of PINK1 or PINK1-CTD suppressed EGFR dimerization, activation, downstream signaling, and tumor growth. These findings identify key elements in the EGFR regulatory cascade and illustrate a new direction for the development of anti-EGFR therapeutics, suggesting translational potential of the PINK1-CTD in lung cancer. SIGNIFICANCE: This study identifies PINK1 as a critical tumor suppressor that impedes EGFR dimerization and highlights PINK1-CTD as a potential therapeutic agent in EGFR-driven lung cancer.

Mortality of Cardiovascular Events in Patients With COPD and Preceding Hospitalization for Acute Exacerbation.

BACKGROUND: Acute exacerbation (AE) of COPD may be accompanied by the deterioration of cardiovascular comorbidities, as evidenced by the increased incidence of acute cardiovascular events. RESEARCH QUESTION: The goal of this study was to determine whether preceding AE might be associated with mortality of cardiovascular events. STUDY DESIGN AND METHODS: Using a health insurance research database in Taiwan, patients with COPD were identified who experienced first-time acute myocardial infarction (AMI; n = 26,442), ischemic stroke (n = 54,959), and intracranial hemorrhage (ICH; n = 14,893) over a 13-year period. In each cohort, 4,356, 6,655, and 1,727 patients, respectively, had been hospitalized for AE within the previous year prior to the index cardiovascular events, and patients with COPD but without hospitalization for AEs constituted the control subjects. ORs of 90-day mortality and hazard ratios (HRs) of overall mortality during follow-up in relation to hospitalization for an AE and the frequency of hospitalization for AEs (ie, 1 and ≥ 2 hospitalizations for AEs) were estimated with adjustment for potential confounders. RESULTS: Hospitalization for an AE was independently associated with 90-day mortality of AMI (OR, 1.33; 95% CI, 1.24-1.43), ischemic stroke (OR, 1.46; 95% CI, 1.36-1.56), and ICH (OR, 1.19; 95% CI, 1.06-1.32). Hospitalization for an AE was associated with overall mortality of AMI (HR, 1.23; 95% CI, 1.19-1.27), ischemic stroke (HR, 1.29; 95% CI, 1.26-1.33), and ICH (HR, 1.19; 95% CI, 1.13-1.26). In addition, compared with control subjects, patients with more frequent hospitalizations for AEs exhibited significant trends at higher risk of 90-day and overall mortality of AMI, ischemic stroke, and ICH. Finally, these results were consistent with propensity score matching-based estimates. INTERPRETATION: Preceding hospitalization for AEs is associated with 90-day and overall mortality of cardiovascular events in COPD.

A Novel TNF-α-Targeting Aptamer for TNF-α-Mediated Acute Lung Injury and Acute Liver Failure.

Rationale: The TNF-α pathway plays as a double-edged sword that simultaneously regulates cell apoptosis and proliferation. The dysregulated TNF-α signaling can trigger cytokine storms that lead to profound cell death during the phase of acute tissue injury. On the other hand, an optimal level of TNF-α signaling is required for tissue repair following the acute injury phase. The TNF-α pathway is commonly upregulated in acute lung injury (ALI) and acute liver failure (ALF). Previous studies investigated the feasibility of adopting protein-based TNF-α blockers as disease modifiers in ALI and ALF, but none of these came out with a positive result. One of the potential reasons that resides behind the failure of the trials might be the long half-life of these inhibitors that led to undesired side effects. Developing alternative TNF-α blockers with manageable half-lives remain an unmet need in this regard. Methods: In the current study, we developed a novel TNF-α-targeting aptamer (aptTNF-α) and its PEG-derivate (aptTNF-α-PEG) with antagonistic functions. We investigated the in vivo antagonistic effects using mouse ALI and ALF models. Results: Our data showed that aptTNF-α possessed good in vitro binding affinity towards human/mouse TNF-α and successfully targeted TNF-α in vivo. In the mouse ALI model, aptTNF-α/aptTNF-α-PEG treatment attenuated the severity of LPS-induced ALI, as indicated by the improvement of oxygen saturation and lung injury scores, the reduction of protein-rich fluid leakage and neutrophil infiltration in the alveolar spaces, and the suppression of pro-inflammatory cytokines/chemokines expressions in the lung tissues. In the mouse ALF model, we further showed that aptTNF-α/aptTNF-α-PEG treatment not only attenuated the degree of hepatocyte damage upon acute injury but also potentiated early regeneration of the liver tissues. Conclusion: The results implicated potential roles of aptTNF-α/aptTNF-α-PEG in ALI and ALF. The data also suggested their translational potential as a new category of TNF-α blocking agent.

Translating Gene Signatures Into a Pathologic Feature: Tumor Necrosis Predicts Disease Relapse in Operable and Stage I Lung Adenocarcinoma.

PURPOSE: The high 5-year disease relapse rate in patients with stage I lung adenocarcinoma indicates the need for additional risk stratification parameters. This study assessed whether gene signatures translate into a pathologic feature for better disease stratification. MATERIALS AND METHODS: The mutual interdependence and risk stratification power of three gene signatures, cell cycle, hypoxia, and mammalian target of rapamycin (mTOR), were investigated in nine cohorts of patients with lung adenocarcinoma and five cohorts of patients with lung squamous cell carcinoma. The translation from gene signatures to a pathologic feature, tumor necrosis, was validated in The Cancer Genome Atlas lung adenocarcinoma cohort. The translation of signature score to pathway activity was further investigated by integrative analyses using The Cancer Genome Atlas and The Cancer Protein Atlas lung adenocarcinoma data sets. RESULTS: The results showed that the three gene signatures were mutually interdependent in lung adenocarcinoma but not in lung squamous cell carcinoma. The signature activities were higher in necrosis-positive tumors than in necrosis-negative tumors. The signature score correlated with the expression level of the representative protein that implicated the activity of each pathway. These signatures stratified patients with operable and stage I lung adenocarcinomas into different risk groups independent of age and stage. Furthermore, the signatures translated to a pathologic feature, tumor necrosis, which predicted shorter overall and relapse-free survival in patients with operable and stage I lung adenocarcinomas. CONCLUSION: This study showed that gene signatures could translate into a pathologic feature, tumor necrosis, with risk stratification ability in patients with operable and stage I lung adenocarcinomas.

Population-Based Cohort Study Reveals Distinct Associations Between Female Lung Cancer and Breast Cancer in Taiwan.

PURPOSE: Associations between Asian lung cancer (LC) and breast cancer (BC) are unknown. This study evaluates associations between LC and BC in the Taiwan population. METHODS: This study was based on the Taiwan National Health Insurance data and Taiwan Cancer Registry. The cohorts included women with newly diagnosed LC or BC between 2000 and 2011 and an age- and sex-stratified random sample as a noncancer comparison cohort during the same period. Cox proportional hazards regression analysis was used to determine the risks. The National Taiwan University Hospital (NTUH) cohort, which comprised patients with confirmed pathology diagnoses of double BC/LC, was reviewed. RESULTS: In 32,824 women with LC, there were increased risks for synchronous BC in patients younger than age 50 years (hazard ratio, 5.80; 95% CI, 1.83 to 18.73), age 50 to 59 years (HR, 2.37; 95% CI, 1.02 to 5.54), and age 60 to 69 years (HR, 4.42; 95% CI, 1.91 to 10.2). In the 88,446 women with BC, there were increased risks for synchronous LC in patients age 40 to 59 years (HR, 5.86; 95% CI, 3.05 to 11.3) and older than 60 years (HR, 1.98; 95% CI, 1.04 to 3.77). In the 128-patient NTUH double LC/BC cohort, 77 (60%) had both cancers diagnosed within 5 years of each other. CONCLUSION: LC is associated with an increased risk for synchronous BC in Taiwan and vice versa. Radiotherapy might not be a major risk factor for LC in BC survivors. Etiology for double LC/BC deserves additional exploration and cross-racial genomic studies.

A CTLA-4 Antagonizing DNA Aptamer with Antitumor Effect.

The successful translation of cytotoxic T lymphocyte antigen-4 (CTLA-4) blockade has revolutionized the concept of cancer immunotherapy. Although monoclonal antibody therapeutics remain the mainstream in clinical practice, aptamers are synthetic oligonucleotides that encompass antibody-mimicking functions. Here, we report a novel high-affinity CTLA-4-antagonizing DNA aptamer (dissociation constant, 11.84 nM), aptCTLA-4, which was identified by cell-based SELEX and high-throughput sequencing. aptCTLA-4 is relatively stable in serum, promotes lymphocyte proliferation, and inhibits tumor growth in cell and animal models. Our study demonstrates the developmental pipeline of a functional CTLA-4-targeting aptamer and suggests a translational potential for aptCTLA-4.