In this article, we summarize the progress made in lung cancer, mesothelioma, and thymic epithelial malignancy during the period 2005-2025. We enlisted multidisciplinary thoracic oncologic experts to tackle this task. The main focus of the article concerns how basic science with translational impact has improved the diagnosis, prognosis, and therapy of these cancers. During the past 20 years, we have come to the realization that "lung cancer" is a name that encompasses tumors with vast histologic, immune, and genomic differences that in turn influence prognosis and response to therapy. For example, programmed death-ligand 1 levels are being used as an immune signature which guides the use of immunotherapy. There is an 85% higher risk for developing lung cancer among first-degree relatives of patients with lung cancer. Accordingly, an increasing number of lung cancers are being identified in carriers of predisposing germline pathogenic inactivating mutations, suggesting that screening programs for early lung cancer detection may benefit family members. Underscoring the role of genetics, and the importance of germline testing, a different variant of mesothelioma has been identified developing in carriers of inactivating heterozygous germline mutations of BAP1 and of other tumor suppressor genes, including a new variant of mesothelioma caused by fusion genes. These variants of mesothelioma are characterized by specific histologic and molecular genetic alterations. These patients benefit from screening programs as they are at risk of multiple malignancies, their tumors are usually much less aggressive, and they are more responsive to therapy compared with sporadic, asbestos-induced mesotheliomas. Thus, the tailored therapeutic approach that is described here for lung cancer may extend to patients with mesothelioma, rather than the previous "one therapy fits all" approach. Progress in the rare thymic epithelial tumors has been less marked; however, recent insights into the biology of thymic tumors have resulted in the development of clinically relevant interventions.

INTRODUCTION:Low-dose computed tomography (LDCT) screening saves lives but is limited by high false-positive rates, necessitating noninvasive risk stratification. The prospective Bio-Multicentric Italian Lung Detection (BioMILD) trial was the first to validate the combination of a plasma microRNA test (MSC) with LDCT to personalize screening intervals. This study integrates a novel immune signature classifier (ISC), based on peripheral blood mononuclear cell profiling, to complement MSC, maximize information from a single blood draw, and further optimize the management of suspicious lung nodules. METHODS:Plasma and peripheral blood mononuclear cell samples were prospectively collected from 304 heavy smokers enrolled in the BioMILD trial who presented with LDCT-detected suspicious nodules and a 7.5-year median follow-up. MSC and ISC tests were determined by real-time quantitative polymerase chain reaction. Grafting of patient-derived xenograft models, obtained from the same patients, was used as indicator of tumor aggressiveness. RESULTS:ISC was associated with age (p = 0.0323) and Lung-RADS (p = 0.0008) and was significantly higher in patients with cancers diagnosed within 2 years (p = 0.0006). Higher ISC values also correlated with successful patient-derived xenograft engraftment (p = 0.0449). In terms of diagnostic performance, the combined ISC and MSC model achieved 96% sensitivity and 98% negative predictive value (NPV) (95% confidence interval: 0.93-0.99). It represented a significant enhancement than MSC alone (ΔNPV = +0.05; 95% confidence interval: 0.01-0.08) and resulted in a 37% reduction of false positives. CONCLUSION:Integration of immune and molecular markers significantly enhances LDCT screening accuracy. The higher NPV achieved by the combined model allows greater confidence in ruling out malignancy among LDCT-detected nodules, thereby reducing unnecessary follow-up examinations and invasive procedures.

Abstract Background: Lung cancer (LC) remains the leading cause of cancer-related mortality worldwide. Despite major therapeutic advances, LC patients still experience poor prognosis. Increasing evidence indicates that tumor-driven hematopoietic remodeling and systemic inflammation actively sustain immune suppression and disease progression. The expansion of immature myeloid populations, particularly myeloid-derived suppressor cells (MDSCs), represents a hallmark of tumor-induced emergency myelopoiesis. However, the composition and developmental hierarchy of circulating MDSC subsets remain unclear. Here, we identify a previously unrecognized subset of circulating early MDSCs (eMDSCs) that mirrors tumor-driven myelopoietic activation and lung cancer progression. Methods: In a prospective discovery cohort including LC patients (n=63) and heavy smokers without cancer (HS, n=52), circulating myeloid subsets were characterized from fresh peripheral blood. Multiparametric flow cytometry enabled comprehensive profiling of peripheral blood mononuclear cells (PBMCs). eMDSCs were defined as CD11b+CD33+CD15- within the Lineage-HLA-DR- compartment. A retrospective validation cohort (LC, n=58; HS, n=58), matched for sex, age, and smoking status, confirmed the findings and explored associations with tumor stage and COPD-related inflammation. FACS-sorted eMDSCs from representative LC and HS samples underwent qPCR analysis for PD-L1 and ARG1 expression. Statistical analyses were performed using the Kruskal-Wallis (KW) and Wilcoxon (WILC) tests. Results: In both discovery and validation cohorts (total n=231), LC patients displayed an increased enrichment of circulating CD11b+ myeloid populations (WILC test p-value: non-significant p=0.052, p=0.001), particularly Lin-HLA-DR-CD33+CD11b+ MDSCs (WILC test p-value: p<0.0001, p=0.009). Within this population, a distinct immature subset of CD15- early MDSCs was identified (WILC test p-value: p<0.0001, p=0.014) and found to be specifically increased in stage II-III LC, but not further expanded at stage IV (KW test p-value: p=0.015). No association emerged between eMDSC levels and COPD-related inflammation, supporting a tumor-specific expansion. Moreover, NK cell frequencies increased in parallel with eMDSCs, suggesting a functional interplay, as eMDSCs may suppress NK activity (KW test p-value: p=0.002). Consistently, qPCR analysis revealed higher PD-L1 and ARG1 expression in LC-derived eMDSCs compared with HS, indicating their immunoregulatory polarization. Conclusion: Our findings identify circulating early MDSCs as a hallmark of lung cancer-associated emergency myelopoiesis. Their selective expansion in stage II-III disease supports their potential as circulating biomarkers to identify and monitor tumor-driven myelopoietic activation and lung cancer progression. Citation Format: Anna Zanichelli, Orazio Fortunato, Mara Lecchi, Paolo Verderio, Luigi Rolli, Ugo Pastorino, Gabriella Sozzi, Claudia Chiodoni, Sabina Sangaletti. Circulating early myeloid-derived suppressor cells as indicators of tumor-driven myelopoiesis and disease progression in lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 1112.

Background Metastatic recurrence represents the major clinical challenge in early-stage lung cancer after curative surgery. Here, we investigated the role of circulating extracellular vesicles and particles (EVPs) in promoting formation of pre-metastatic niches (PMNs).Methods Plasma-derived EVPs were obtained by ultracentrifugation from pre-surgery blood samples of patients with poor prognosis. Heavy-smokers cancer free individuals were used as control. EVP were characterized following MISEV guidelines. Functional experiments were carried out in vitro in 2D and 3D-bioprinted models as well as in vivo.Results EVPs from patients with early relapse show distinct molecular profiles, characterized by elevated levels of miR-29a and complement protein C4a. These EVPs preferentially target endothelial cells inducing a pro-inflammatory condition with upregulation of VCAM1 and CXCL1. In turn, endothelial modulation stimulated fibroblast activation and promoted neutrophils recruitment supporting PMNs formation. Mechanistically, we demonstrate that miR-29a and C4A act synergistically through SPARC down-modulation promoting cancer cell colonization. Preconditioning of mouse lungs using EVPs from patients with poor prognosis increased metastatic growth of human tumor cells, which was inhibited by miR-29a blockade.Conclusions Circulating EVPs could be novel prognostic biomarkers and key players in PMN formation offering new targets to reduce relapses in lung cancer.

Low-dose computed tomography (LDCT) lung cancer screening can reduce mortality in high-risk individuals, but many individuals with a heavy smoking history may be reluctant to undergo radiologic examinations. A non-invasive blood test might help overcome this barrier. The BioMILD trial evaluated the combination of a plasma microRNA signature classifier (MSC) and LDCT for personalized lung cancer screening in 4,119 individuals who smoke or used to smoke. Based on BioMILD results, we aim to conduct a projection analysis to estimate the number of early lung cancers that could be detected if MSC were used as an initial screening tool for individuals reluctant to undergo LDCT. This model explores the potential of a biomarker-driven approach to address screening hesitation. The analysis focuses on 3,139 volunteers meeting NLST criteria. At baseline, 24.9

Supplementary Data from Development of a Molecular Blood-Based Immune Signature Classifier as Biomarker for Risks Assessment in Lung Cancer Screening

Supplementary Table 1A, B, C, D and E

PURPOSE:Despite the significant improvement in outcomes for patients with advanced non-small cell lung cancer (NSCLC) treated with immune checkpoint inhibitors (ICIs), resistance, whether primary or secondary, remains a substantial challenge. Currently, reliable biomarkers to monitor ICI response are lacking, highlighting the need for minimally invasive tools like liquid biopsy to track treatment efficacy. This study aimed to identify circulating microRNAs (miRNAs) as potential biomarkers to track ICI response in patients with NSCLC. MATERIALS AND METHODS:The Apollo longitudinal study enrolled patients with advanced NSCLC receiving ICI in first or subsequent lines. Plasma samples were collected at baseline and follow-up to prospectively assess miRNA profiles until progressive disease (PD). Using a custom reverse transcription-quantitative polymerase chain reaction platform, 276 ratios among 24 lung cancer-related miRNAs were analyzed. The generalized estimating equation and joint models were applied to select the miRNA ratios most associated with PD over time. To control for multiple testing, the Benjamini-Yekutieli method was applied setting a 10% false discovery rate threshold. RESULTS:From the 211 patients, a total of 454 plasma samples were analyzed. Clinical and biochemical variables had little effect on miRNAs' profile. The analysis identified nine miRNA ratios, all involving miR-145-5p, as significant biomarkers for monitoring treatment response, even after adjustment for the line of therapy. These ratios exhibited a longitudinal modulation pattern consistent with radiologic response, particularly in patients who initially benefited from ICI treatment. In addition, in an independent set of 32 plasma samples from 10 patients receiving ICI as maintenance therapy, the same trends were observed. CONCLUSION:A focused panel of miRNA ratios, driven by miR-145-5p, effectively reflects response to ICI therapy in patients with advanced NSCLC, highlighting their potential as biomarkers for treatment monitoring.

Supplementary methods and materials

Abstract Background. Lung cancer (LC) patients, despite innovative cancer treatments such as target and immune-therapies, still have the poorest five-year survival rate. In this context the possibility of an early detection can anticipate therapeutic intervention, avoiding aggressive therapies thus prolonging disease-free and overall survival. Therefore, the identification of new circulating early biomarkers still represents a relevant clinical need. Methods. Lung cancer (LC) patients (n=63) and heavy smokers (HS) cancer free-subjects (n=52) were evaluated for the enrichment of specific subtypes of myeloid cells. Circulating early myeloid derived suppressor cells (eMDSCs) and low-density neutrophils (LDNs) were assessed by flow cytometry on peripheral blood mononuclear cells (PMBCs). Early MDSCs were defined as CD11b+CD33+CD15-CD14- cells among Lineage negative (Lin-) HLA-DR- PBMCs, whereas LDNs were defined as CD66b+CD15+ cells within the gate of CD11b+ PBMCs. Mature and immature subtypes were discriminated according to the expression of CD10. Results. Performing a sex- and smoking -matched case-control analysis in 39 LC and 39 HS subjects we were able to compare the capacity of specific myeloid population to discriminate lung cancer patients from heavy smokers. The analysis showed significantly higher values of eMDSC (OR=1.12; 95% Confidence Interval (CI) 1.03-1.21), total LDN (CD66b+CD15+; OR=1.23; 95%CI 1.04-1.45) and of mature CD10+ LDN (OR=1.30; 95%CI 1.05-1.61). Moreover, within the overall cohort of 63 LC patients, we analyzed the distributions of the different myeloid populations according to stage (I-II vs III-IV). In this comparison, total LDN (CD66b+CD15+; Kruskal-Wallis (KW) Test p-value=0.014), and mature CD10+ LDN (KW test p-value=0.006) showed significant different distributions according to tumor stage, observing higher values in patients with advanced stage. On the contrary, no difference among stages was observed for the eMDSC population. Conclusions. These findings point to eMDSCs as an early marker for lung cancer detection whereas LDN could be as well associated with disease progression. Citation Format: Orazio Fortunato, Barbara Bassani, Mara Lecchi, Paolo Verderio, Ugo Pastorino, Gabriella Sozzi, Mario Paolo Colombo, Sabina Sangaletti. Circulating early myeloid derived suppressor cells as biomarkers for early detection of lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1060.

Lynch syndrome (LS) is an inherited condition characterized by an increased risk of developing cancer, in particular colorectal cancer (CRC). Microsatellite instability (MSI) is the main feature of (pre)cancerous lesions occurring in LS patients. Close endoscopic surveillance is the only option available to reduce CRC morbidity and mortality. However, it may fail to intercept interval cancers and patients’ compliance to such an invasive procedure may decrease over the years. The development of a minimally invasive test able to detect (pre)cancerous colorectal lesions, could thus help tailor surveillance programs in LS patients. Taking advantage of an endoscopic surveillance program, we retrospectively assessed the instability of five microsatellites (BAT26, BAT25, NR24, NR21, and Mono27) in liquid biopsies collected at baseline and possibly at two further endoscopic rounds. For this purpose, we tested a new multiplex drop-off digital polymerase chain reaction (dPCR) assay, reaching mutant allele frequencies (MAFs) as low as 0.01%. Overall, 78 plasma samples at the three time-points from 18 patients with baseline (pre)cancerous lesions and 18 controls were available for molecular analysis. At baseline, the MAFs of BAT26, BAT25 and NR24 were significantly higher in samples of patients with lesions but did not differ with respect to the grade of dysplasia or any other clinico-pathological characteristics. When all markers were combined to determine MSI in blood, this test was able to discriminate lesion-bearing patients with an AUC of 0.80 (95%CI: 0.66; 0.94).

Background About 10% of NSCLCs are mutated in KRAS and impaired in STK11/LKB1 , a genetic background associated with poor prognosis, caused by an increase in metastatic burden and resistance to standard therapy. LKB1 is a protein involved in a number of biological processes and is particularly important for its role in the regulation of cell metabolism. LKB1 alterations lead to protein loss that causes mitochondria and metabolic dysfunction that makes cells unable to respond to metabolic stress. Different studies have shown how it is possible to interfere with cancer metabolism using metformin and caloric restriction (CR) and both modify the tumor microenvironment (TME), stimulating the switch from “cold” to “hot”. Given the poor therapeutic response of KRAS mut / LKB1 mut patients, and the role of LKB1 in cell metabolism, we examined whether the addition of metformin and CR enhanced the response to chemo or chemo-immunotherapy in LKB1 impaired tumors. Methods Mouse cell lines were derived from lung nodules of transgenic mice carrying KRAS G12D with either functional LKB1 (KRAS G12D /LKB1 wt ) or mutated LKB1 (KRAS G12D /LKB1 mut ). Once stabilized in vitro, these cell lines were inoculated subcutaneously and intramuscularly into immunocompetent mice. Additionally, a patient-derived xenograft (PDX) model was established by directly implanting tumor fragments from patient into immunocompromised mice. The mice bearing these tumor models were subjected to treatment with chemotherapy or chemo-immunotherapy, both as standalone regimens and in combination with metformin and CR. Results Our preclinical results indicate that in NSCLC KRAS mut / LKB1 mut tumors, metformin and CR do enhance the response to chemo and chemo-immunotherapy, inducing a metabolic stress condition that these tumors are not able to overcome. Analysis of immune infiltrating cells did not bring to light any strong correlation between the TME immune-modulation and the tumor response to metformin and CR. Conclusion Our in vitro and in vivo preliminary studies confirm our hypothesis that the addition of metformin and CR is able to improve the antitumor activity of chemo and chemoimmunotherapy in LKB1 impaired tumors, exploiting their inability to overcome metabolic stress.

Background:The proper management of suspicious radiologic findings is crucial to optimize the effectiveness of low-dose computed tomography (LDCT) lung cancer screening trials. In the BioMILD study, we evaluated the utility of combining a plasma 24-microRNA signature classifier (MSC) and LDCT to define the individual risk and personalize screening strategies. Here we aim to assess the utility of repeated MSC testing during annual screening rounds in 1024 participants with suspicious LDCT findings. Methods:The primary outcome was two-year lung cancer incidence in relation to MSC test results, reported as relative risk (RR) with 95% confidence interval (CI). Lung cancer incidence and mortality were estimated using extended Cox models for time-dependent covariates, yielding the respective hazard ratios (HR). Clinicaltrials.gov ID: NCT02247453. Findings:With a median follow-up of 8.5 years, the full study set included 1403 indeterminate LDCT (CTind) and 584 positive LDCT (CT+) results. A lung cancer RR increase in MSC+ compared to MSC- participants was observed in both the CTind (RR: 2.5; 95% CI: 1.4-4.32) and CT+ (RR: 2.6; 95% CI: 1.81-3.74) groups and was maintained when considering stage I or resectable tumors only. A 98% negative predictive value in CTind/MSC- and a 30% positive predictive value in CT+/MSC+ lesions were recorded. At seven years' follow-up, MSC+ participants had a cumulative HR of 4.4 (95% CI: 3.0-6.4) for lung cancer incidence and of 8.1 (95% CI: 2.7-24.5) for lung cancer mortality. Interpretation:Our study shows that MSC can be reliably performed during LDCT screening rounds to increase the accuracy of lung cancer risk and mortality prediction and supports its clinical utility in the management of LDCT findings of uncertain malignancy. Funding:Italian Association for Cancer Research; Italian Ministry of Health; Horizon2020; National Cancer Institute (NCI); Gensignia LifeScience.

Background Epithelial to mesenchymal transition (EMT) endows cancer cells with pro-metastatic properties, which appear most effective when cells enter an intermediate hybrid (H) state, characterized by integrated mesenchymal (M) and epithelial (E) traits. The reasons for this advantage are poorly known and, especially, it is totally unexplored whether the interplay between H-cells and NK cells could have a role. Here we characterize the pro-metastatic mechanics of non-small cell lung cancer (NSCLC) H-cells and their subset of cancer-initiating cells (CICs), dissecting crucial interactions with NK cells.Methods Human lung cancer cell lines and sublines representative of E, M, or H states, assessed by proteomics, were analyzed in vivo for their tumor-forming and disseminating capabilities. Interactions with NK cells were investigated in vitro using migration assays, cytotoxic degranulation assays, and evaluation of CD133+ CICs modulation after coculture, and validated in vivo through NK cell neutralization assays. Correlation between EMT status, NK cell infiltration, and survival data, was evaluated in a cohort of surgically resected NSCLC cases (n=79).Results We demonstrated that H-cells, have limited dissemination capability but show the highest potential to initiate metastases in vivo. This property was related to their ability to escape NK cell surveillance. Mechanistically, H-cells expressed low levels of NK-attracting chemokines (CXCL1 and CXCL8), generating poorly infiltrated metastases. Accordingly, proteomics and GO enrichment analysis of E, H, M cell lines showed that the related secretory processes could change during EMT.Furthermore, H-CICs uniquely expressed high levels of the inhibitory ligand B7-H3, which protected H-CIC from NK cell-mediated clearance. In vivo neutralization assays confirmed that, indeed, the pro-metastatic properties of H-cells are poorly controlled by NK cells.Finally, the analysis of patients revealed that detection of hybrid phenotypes associated with low NK infiltration in NSCLC clinical specimens could identify a subset of patients with poor prognosis.Conclusions Our study demonstrates that H-cells play a central role in the metastatic spread in NSCLC. Such pro-metastatic advantage of H-cells is supported by their altered interaction with NK cells and by the critical role of B7-H3 in preserving their H-CIC component, indicating B7-H3 as a potential target in combined NK-based therapies.

Abstract Background: Platinum-based neoadjuvant chemotherapy (pb-NACT) is the primary treatment approach for locally advanced non-small cell lung cancer (LA-NSCLC), despite offering only a limited overall survival (OS) gain. Cisplatin-induced cell damage has been shown to activate the SDF-1/CXCR4 axis in preclinical models of NSCLC, resulting in the recruitment of a cell subset co-expressing the stemness marker CD133 and CXCR4 (SDF-1 receptor) at distant sites. These cells, known as metastasis-initiating cells (MIC), exhibit prometastatic activity. By longitudinally monitoring circulating tumor cells (CTC) in the blood of LA-NSCLC patients (pts) undergoing pb-NACT, our objective is to assess the potential prognostic significance of CTC number and phenotype. Methods: Between February 2019 and August 2023, a total of 61 pts with LA-NSCLC undergoing pb-NACT, were included in the study. Blood samples were obtained at baseline (T1), post-pb-NACT (T2), and post-surgery (T3) for the characterization of CTC, including total CTC, CXCR4+CTCs, and CXCR4+CD133+ MIC. This characterization utilized a validated marker-independent strategy combining Parsortix and DEPArrayTM technologies. Logistic regression models were employed to examine the association between CTC subsets and the response to pb-NACT (Disease Control Rate [DCR], Overall Response Rate [ORR]), while Cox-regression models were used to assess their association with survival endpoints (event-free survival [EFS], OS, disease-free survival [DFS]). Results: Out of the 61 enrolled patients, 34 had available CTC data for analysis. In this population, DCR was 64.7%, and the ORR 29.4%. Surgery was performed in 14 pts (41.2%). At baseline (T1), elevated levels of CXCR4+CTCs were linked to a lower DCR (10 vs 3/mL, odds ratio [OR]=0.02, 95% confidence interval [CI]: 0-0.40, p=0.008), as well as shorter EFS (10 vs 3/mL, HR=4.20, 95% CI: 1.84-9.58, p=0.002) and OS (10 vs 3/mL, HR=3.14, 95% CI: 1.25-7.88, p=0.004). At the post- CT time point (T2), higher levels of MIC were associated with shorter EFS (3 vs 0/mL, HR=1.41, 95% CI: 1.00-1.99, p=0.047) and OS (3 vs 0/mL, HR=1.55, 95% CI: 1.03-2.34, p=0.035). Although the sample size was limited, a higher number of MIC at the post-surgery time point (T3) showed a trend toward reduced DFS. Discussion: CTC could serve as a novel biomarker for assessing the effectiveness of pb-NACT in LA-NSCLC. Elevated levels of CXCR4+CTC both at baseline and after pb-NACT, along with increased MIC post-pb-NACT and post-surgery, indicate unfavorable prognostic factors for survival. Specifically, a higher baseline of CXCR4+CTCs may be linked to a suboptimal response to treatment, suggesting the potential need for treatment intensification in patients exhibiting elevated CXCR4+CTC baseline levels. Citation Format: Rita Leporati, Teresa Beninato, Sara Iadecola, Chiara Andreon, Fabio Murianni, Melissa Balsamo, Antonia Martinetti, Benedetta Lombardi Stocchetti, Laura Mazzeo, Sara Manglaviti, Mario Occhipinti, Marta Brambilla, Arsela Prelaj, Claudia Proto, Rosalba Miceli, Luca Roz, Gabriella Sozzi, Filippo De Braud, Giuseppe Lo Russo, Giulia Bertolini. Dissecting circulating tumor cells phenotype in a cohort of locally advanced non-small cell lung cancer patients undergoing neoadjuvant chemotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3702.