Development of a small cell lung cancer organoid model to study cellular interactions and survival after chemotherapy

Challenges of small cell lung cancer heterogeneity and phenotypic plasticity

Small cell lung cancer (SCLC) is an aggressive neuroendocrine malignancy with ~7% 5-year overall survival reflecting early metastasis and rapid acquired chemoresistance. Immunotherapy briefly extends overall survival in ~15% cases, yet predictive biomarkers are lacking. Targeted therapies are beginning to show promise, with a recently approved delta-like ligand 3 (DLL3)-targeted therapy impacting the treatment landscape. The increased availability of patient-faithful models, accumulating human tumour biobanks and numerous comprehensive molecular profiling studies have collectively facilitated the mapping and understanding of substantial intertumoural and intratumoural heterogeneity. Beyond the almost ubiquitous loss of wild-type p53 and RB1, SCLC is characterized by heterogeneously mis-regulated expression of MYC family members, yes-associated protein 1 (YAP1), NOTCH pathway signalling, anti-apoptotic BCL2 and epigenetic regulators. Molecular subtypes are based on the neurogenic transcription factors achaete-scute homologue 1 (ASCL1) and neurogenic differentiation factor 1 (NEUROD1), the rarer non-neuroendocrine transcription factor POU class 2 homeobox 3 (POU2F3), and immune- and inflammation-related signatures. Furthermore, SCLC shows phenotypic plasticity, including neuroendocrine-to-non-neuroendocrine transition driven by NOTCH signalling, which is associated with disease progression, chemoresistance and immune modulation and, in mouse models, with metastasis. Although these features pose substantial challenges, understanding the molecular vulnerabilities of transcription factor subtypes, the functional relevance of plasticity and cell cooperation offer opportunities for personalized therapies informed by liquid and tissue biomarkers.

Unveiling radiobiological traits and therapeutic responses of BRAFV600E-mutant colorectal cancer via patient-derived organoids

BACKGROUND

Radiotherapy (RT) is an essential treatment for colorectal cancer (CRC), yet the factors influencing radiosensitivity remain unclear. In the quest to enhance the therapeutic efficacy in CRC, the interplay between genetic mutations and RT sensitivity has emerged as a pivotal yet enigmatic area.

METHODS

We harness the fidelity of patient-derived organoids (PDOs) to dissect the molecular landscape of radiosensitivity, with a particular emphasis on BRAFV600E mutations. To further investigate, a cohort of 9 BRAFV600E-mutant and 10 BRAF wild-type PDOs is constructed to systematically assess the radiobiological traits of BRAFV600E-mutant CRC, including morphology, cell viability, and DNA damage, while also evaluating their responses to chemotherapy and chemoradiotherapy.

RESULTS

Our systematic investigation unveils a profound correlation between BRAFV600E mutation status and radioresistance, which is validated by clinical treatment responses. Intriguingly, BRAFV600E-mutant PDOs exhibit reduced sensitivity to conventional chemotherapy, yet demonstrate an enhanced response to combined chemoradiotherapy, characterized by increased apoptosis. The results are validated through in vivo analyses using patient-derived organoid xenograft mouse models and aligned with patient clinical outcomes.

CONCLUSIONS

This study outlines the distinct radiobiological profile of BRAFV600E-mutant CRC, underscoring the critical role of radiotherapy in comprehensive treatment strategies. This work not only advances our molecular understanding of CRC but also paves the way for precision medicine, offering valuable insights for therapeutic decision-making in the clinical management of BRAFV600E-mutant CRC.

Navigating the Complexity of Resistance in Lung Cancer Therapy: Mechanisms, Organoid Models, and Strategies for Overcoming Treatment Failure

Background: The persistence of chemotherapy-resistant and dormant cancer cells remains a critical challenge in the treatment of lung cancer. Objectives: This review focuses on non-small cell lung cancer and small cell lung cancer, examining the complex mechanisms that drive treatment resistance. Methods: This review analyzed current studies on chemotherapy resistance in NSCLC and SCLC, focusing on tumor microenvironment, genetic mutations, cancer cell heterogeneity, and emerging therapies. Results: Conventional chemotherapy and targeted therapies, such as tyrosine kinase inhibitors, often fail due to factors including the tumor microenvironment, genetic mutations, and cancer cell heterogeneity. Dormant cancer cells, which can remain undetected in a quiescent state for extended periods, pose a significant risk of recurrence upon reactivation. These cells, along with intrinsic resistance mechanisms, greatly complicate treatment efforts. Understanding these pathways is crucial for the development of more effective therapies. Emerging strategies, including combination therapies that target multiple pathways, are under investigation to improve treatment outcomes. Innovative approaches, such as antibody-drug conjugates and targeted protein degradation, offer promising solutions by directly delivering cytotoxic agents to cancer cells or degrading proteins that are essential for cancer survival. The lung cancer organoid model shows substantial promise to advance both research and clinical applications in this field, enhancing the ability to study resistance mechanisms and develop personalized treatments. The integration of current research underscores the need for continuous innovation in treatment modalities. Conclusions: Personalized strategies that combine novel therapies with an in-depth understanding of tumor biology are essential to overcome the challenges posed by treatment-resistant and dormant cancer cells in lung cancer. A multifaceted approach has the potential to significantly improve patient outcomes.

Activating Invasion and Metastasis in Small Cell Lung Cancer: Role of the Tumour Immune Microenvironment and Mechanisms of Vasculogenesis, Epithelial-Mesenchymal Transition, Cell Migration, and Organ Tropism

BACKGROUND

Small cell lung cancer (SCLC) harbours the most aggressive phenotype of all lung cancers to correlate with its bleak prognosis. The aggression of SCLC is partially attributable to its strong metastatic tendencies. The biological processes facilitating the metastasis in SCLC are still poorly understood and garnering a deeper understanding of these processes may enable the exploration of additional targets against this cancer hallmark in the treatment of SCLC.

RECENT FINDINGS

This narrative review will discuss the proposed molecular mechanisms by which the cancer hallmark of activating invasion and metastasis is featured in SCLC through important steps of the metastatic pathway, and address the various molecular targets that may be considered for therapeutic intervention. The tumour immune microenvironment plays an important role in facilitating immunotherapy resistance, whilst the poor infiltration of natural killer cells in particular fosters a pro-metastatic environment in SCLC. SCLC vasculogenesis is achieved through VEGF expression and vascular mimicry, and epithelial-mesenchymal transition is facilitated by the expression of the transcriptional repressors of E-cadherin, the suppression of the Notch signalling pathway and tumour heterogeneity. Nuclear factor I/B, selectin and B1 integrin hold important roles in SCLC migration, whilst various molecular markers are expressed by SCLC to assist organ-specific homing during metastasis. The review will also discuss a recent article observing miR-1 mRNA upregulation as a potential therapeutic option in targeting the metastatic activity of SCLC.

CONCLUSION

Treatment of SCLC remains a clinical challenge due to its recalcitrant and aggressive nature. Amongst the many hallmarks used by SCLC to enable its aggressive behaviour, that of its ability to invade surrounding tissue and metastasise is particularly notable and understanding the molecular mechanisms in SCLC metastasis can identify therapeutic targets to attenuate SCLC aggression and improve mortality.

Patient-derived organoids and mini-PDX for predicting METN375S-mutated lung cancer patient clinical therapeutic response

Lung cancer as a molecularly and histologically high heterogonous disease, there is an urgent need to predict lung cancer patients' responses to anti-cancer treatment, and patient-derived organoids (PDOs) have been recognized as a valuable platform for preclinical drug screening. In this study, we successfully established 26 PDO lines from various subtypes of lung cancers including benign tumor, adenocarcinoma, squamous cell carcinoma, adenosquamous carcinoma, large-cell carcinoma, and small-cell carcinoma. These PDOs were shown to retain the major genomic and histological characteristics of primary tumors and remain stable during long-term culture. With the help of targeted genomic sequencing, we found that lung cancer that harbors METN375S mutation is selectively sensitive to afatinib, and a combination of afatinib and gemcitabine induced synthetic lethality in PDO and mini-PDX models. In summary, our findings demonstrate the potential of PDO in predicting lung cancer drug response, and reveal a promising strategy for METN375S mutant lung cancer treatment.

3D cell culture models in research: applications to lung cancer pharmacology

Lung cancer remains one of the leading causes of cancer-related mortality worldwide, necessitating innovative research methodologies to improve treatment outcomes and develop novel strategies. The advent of three-dimensional (3D) cell cultures has marked a significant advancement in lung cancer research, offering a more physiologically relevant model compared to traditional two-dimensional (2D) cultures. This review elucidates the various types of 3D cell culture models currently used in lung cancer pharmacology, including spheroids, organoids and engineered tissue models, having pivotal roles in enhancing our understanding of lung cancer biology, facilitating drug development, and advancing precision medicine. 3D cell culture systems mimic the complex spatial architecture and microenvironment of lung tumours, providing critical insights into the cellular and molecular mechanisms of tumour progression, metastasis and drug responses. Spheroids, derived from commercialized cell lines, effectively model the tumour microenvironment (TME), including the formation of hypoxic and nutrient gradients, crucial for evaluating the penetration and efficacy of anti-cancer therapeutics. Organoids and tumouroids, derived from primary tissues, recapitulate the heterogeneity of lung cancers and are instrumental in personalized medicine approaches, supporting the simulation of in vivo pharmacological responses in a patient-specific context. Moreover, these models have been co-cultured with various cell types and biomimicry extracellular matrix (ECM) components to further recapitulate the heterotypic cell-cell and cell-ECM interactions present within the lung TME. 3D cultures have been significantly contributing to the identification of novel therapeutic targets and the understanding of resistance mechanisms against conventional therapies. Therefore, this review summarizes the latest findings in drug research involving lung cancer 3D models, together with the common laboratory-based assays used to study drug effects. Additionally, the integration of 3D cell cultures into lung cancer drug development workflows and precision medicine is discussed. This integration is pivotal in accelerating the translation of laboratory findings into clinical applications, thereby advancing the landscape of lung cancer treatment. By closely mirroring human lung tumours, these models not only enhance our understanding of the disease but also pave the way for the development of more effective and personalized therapeutic strategies.

Mesenchymal Stromal Cell Therapy for Thoracic Surgeons: An Update

Stem cells are undifferentiated cells presenting extensive self-renewal features and the ability to differentiate "in vitro" and "in vivo" into a range of lineage cells, like chondrogenic, osteogenic and adipogenic lineages when cultured in specific inducing media. Two major domains of clinical applications of stem cells in thoracic surgery have been investigated: regenerative medicine, which is a section of translational research in tissue engineering focusing on the replacement, renewal or regeneration of cells, tissues and organs to re-establish damaged physiologic functions; drug loading and delivery, representing a new branch proposing stem cells as carriers to provide selected districts with anti-cancer agents for targeted treatments.