An orthotopic mouse model of small cell lung cancer reflects the clinical course in patients

Transcriptomic profiling and risk assessment in bladder cancer: Insights from copper death-related genes

BACKGROUND

The study aimed to investigate the role of copper death-related genes (CRGs) in bladder cancer (BC) for improved prognosis assessment.

METHODS

Multi-omics techniques were utilized to analyze CRG expression in BC tissues from TCGA and GEO databases. Consensus clustering categorized patients into molecular subtypes based on clinical characteristics and immune cell infiltration.

RESULTS

An innovative risk assessment model identified eight critical genes associated with BC risk. In vitro and in vivo experiments validated LIPT1's significant impact on copper-induced cell death, proliferation, migration, and invasion in BC.

CONCLUSION

This multi-omics analysis elucidates the pivotal role of CRGs in BC progression, suggesting enhanced risk assessment through molecular subtype categorization and identification of key genes like LIPT1. Insights into these mechanisms offer the potential for improved diagnosis and treatment strategies for BC patients.

New genetic insights into immunotherapy outcomes in gastric cancer via single-cell RNA sequencing and random forest model

OBJECTIVE

The high mortality rate of gastric cancer, traditionally managed through surgery, underscores the urgent need for advanced therapeutic strategies. Despite advancements in treatment modalities, outcomes remain suboptimal, necessitating the identification of novel biomarkers to predict sensitivity to immunotherapy. This study focuses on utilizing single-cell sequencing for gene identification and developing a random forest model to predict immunotherapy sensitivity in gastric cancer patients.

METHODS

Differentially expressed genes were identified using single-cell RNA sequencing (scRNA-seq) and gene set enrichment analysis (GESA). A random forest model was constructed based on these genes, and its effectiveness was validated through prognostic analysis. Further, analyses of immune cell infiltration, immune checkpoints, and the random forest model provided deeper insights.

RESULTS

High METTL1 expression was found to correlate with improved survival rates in gastric cancer patients (P = 0.042), and the random forest model, based on METTL1 and associated prognostic genes, achieved a significant predictive performance (AUC = 0.863). It showed associations with various immune cell types and negative correlations with CTLA4 and PDCD1 immune checkpoints. Experiments in vitro and in vivo demonstrated that METTL1 enhances gastric cancer cell activity by suppressing T cell proliferation and upregulating CTLA4 and PDCD1.

CONCLUSION

The random forest model, based on scRNA-seq, shows high predictive value for survival and immunotherapy sensitivity in gastric cancer patients. This study underscores the potential of METTL1 as a biomarker in enhancing the efficacy of gastric cancer immunotherapy.

A mouse model of lung cancer induced via intranasal injection for anticancer drug screening and evaluation of pathology

The pathologies and lethality of lung cancers are associated with smoking, lifestyle, and genomic factors. Several experimental mouse models of lung cancer, including those induced via intrapulmonary injection and intratracheal injection, have been reported for evaluating the pharmacological effect of drugs. However, these models are not sufficient for evaluating the efficacy of drugs during screening, as these direct injection models ignore the native processes of cancer progression in vivo, resulting in the inadequate pathological formation of lung cancer. In the present study, we developed a novel intranasal injection model of lung cancer simulating the native lung cancer pathology for anticancer drug screening. A mouse lung cancer cell line (Lewis lung carcinoma; LCC) was intranasally injected into mouse lungs, and injected cell number-dependent cancer proliferation was apparent in both the left and right lungs. Human non-small-cell lung cancer (NCI-H460) cells were also intranasally injected into nude mice and similarly showed injected cell number-dependent cancer growth. For the pharmacological evaluation of cisplatin, two different treatment frequencies were tested four times per month and twice a month. The intranasal injection model confirmed that cisplatin suppressed lung cancer progression to a greater extent under the more frequent treatment condition. In conclusion, these results indicated that our intranasal injection model is a powerful tool for investigating lung cancer pathology and may aid in the development of new anti-lung cancer agents.

Comparative characteristics of small cell lung cancer and Ewing's sarcoma: a narrative review

Background and Objective

Small cell lung cancer (SCLC) and Ewing's sarcoma (ES) at the disseminated stage are not amenable to therapy and have a dismal prognosis with low survival rates. Despite representing different tumor entities, treatment for both malignancies relies on cytotoxic chemotherapy that has not considerably changed for the past decades. The genomic background has been extensively studied and found to comprise inactivation of p53 and RB1 in case of SCLC and EWSR1/FLI1 rearrangement in case of ES resulting in aggressive tumors in adults with heavy tobacco consumption and as bone tumor in juveniles, respectively. New therapeutic modalities are urgently needed to improve the outcomes of both tumor entities, especially in patients with metastatic disease or recurrences. This review summarizes the common cell biologic and clinical characteristics of difficult-to-treat SCLC and ES and discusses their refractoriness and options to improve the therapeutic efficacy.

Methods

PubMed and Euro PMC were searched from January 1^st, 2012 to January 16^th, 2022 using the following key words: "SCLC", "Ewing´s sarcoma", "Genomics" and "Chemoresistance" as well as own work.

Key Content and Findings

Therapy of SCLC and ES involves the use of undirected cytotoxic drugs in multimodal chemotherapy and administration of topotecan for 2^nd line SCLC regimens. Despite highly aggressive chemotherapies, outcomes are dismal for patients with disseminated tumors. A host of unrelated drugs and targeted therapeutics have failed to result in progress for the patients and the underlying mechanisms of chemoresistance are still not clear. Identification of chemoresistance-reversing modulators in vitro and patient-derived xenografts of SCLC and ES has not translated into new therapies.

Conclusions

The global chemoresistance of SCLC and ES may be explained by physiological resistance at the tumor level and formation of larger spheroids that contain quiescent and hypoxic tumor cells in regions that occlude therapeutics. This type of chemoresistance is difficult to overcome and prevent the accumulation of effective drug concentration at the tumor cell level to a significant degree leaving therapeutic interventions of any kind ineffective.

Enhanced AC133-specific CAR T cell therapy induces durable remissions in mice with metastatic small cell lung cancer

Metastatic small cell lung cancer (SCLC) is not curable. While SCLC is initially sensitive to chemotherapy, remissions are short-lived. The relapse is induced by chemotherapy-selected tumor stem cells, which express the AC133 epitope of the CD133 stem cell marker. We studied the effectiveness of AC133-specific CAR T cells post-chemotherapy using human primary SCLC and an orthotopic xenograft mouse model. AC133-specific CAR T cells migrated to SCLC tumor lesions, reduced the tumor burden, and prolonged survival in a humanized orthotopic SCLC model, but were not able to entirely eliminate tumors. We identified CD73 and PD-L1 as immune-escape mechanisms and combined PD-1-inhibition and CD73-inhibition with CAR T cell treatment. This triple-immunotherapy induced cures in 25% of the mice, without signs of graft-versus-host disease or bone marrow failure. AC133⁺ cancer stem cells and PD-L1⁺CD73⁺ myeloid cells were detectable in primary human SCLC tissues, suggesting that patients may benefit from the triple-immunotherapy. We conclude that the combination of AC133-specific CAR T cells, anti-PD-1-antibody and CD73-inhibitor specifically eliminates chemo-resistant tumor stem cells, overcomes SCLC-mediated T cell inhibition, and might induce long-term complete remission in an otherwise incurable disease.

Enhanced AC133-specific CAR T cell therapy induces durable remissions in mice with metastatic small cell lung cancer

Metastatic small cell lung cancer (SCLC) is not curable. While SCLC is initially sensitive to chemotherapy, remissions are short-lived. The relapse is induced by chemotherapy-selected tumor stem cells, which express the AC133 epitope of the CD133 stem cell marker. We studied the effectiveness of AC133-specific CAR T cells post-chemotherapy using human primary SCLC and an orthotopic xenograft mouse model. AC133-specific CAR T cells migrated to SCLC tumor lesions, reduced the tumor burden, and prolonged survival in a humanized orthotopic SCLC model, but were not able to entirely eliminate tumors. We identified CD73 and PD-L1 as immune-escape mechanisms and combined PD-1-inhibition and CD73-inhibition with CAR T cell treatment. This triple-immunotherapy induced cures in 25% of the mice, without signs of graft-versus-host disease or bone marrow failure. AC133⁺ cancer stem cells and PD-L1⁺CD73⁺ myeloid cells were detectable in primary human SCLC tissues, suggesting that patients may benefit from the triple-immunotherapy. We conclude that the combination of AC133-specific CAR T cells, anti-PD-1-antibody and CD73-inhibitor specifically eliminates chemo-resistant tumor stem cells, overcomes SCLC-mediated T cell inhibition, and might induce long-term complete remission in an otherwise incurable disease.

Preclinical Applications of Magnetic Resonance Imaging in Oncology

The evolving possibilities of molecular imaging (MI) are fundamentally changing the way we look at cancer, with imaging paradigms now shifting away from basic morphological measures toward the longitudinal assessment of functional, metabolic, cellular, and molecular information in vivo. Recent developments of imaging methodology and probe molecules utilizing the vast number of novel animal models of human cancers have enhanced our ability to non-invasively characterize neoplastic tissue and follow anticancer treatments. While preclinical molecular imaging offers a whole palette of excellent methodology to choose from, we will focus on magnetic resonance imaging (MRI) techniques, since they provide excellent molecular imaging capabilities and bear high potential for clinical translation. Prerequisites and consequences of using animal models as surrogates of human cancers in preclinical molecular imaging are outlined. We present physical principles, values, and limitations of MRI as molecular imaging modality and comment on its high potential to non-invasively assess information on metabolism, hypoxia, angiogenesis, and cell trafficking in preclinical cancer research.

Pre-clinical models of small cell lung cancer and the validation of therapeutic targets

Introduction: Small-cell lung cancer (SCLC) is an aggressive form of lung cancer that has a dismal prognosis. One of the factors hindering therapeutic developments for SCLC is that most SCLC is not surgically resected resulting in a paucity of material for analysis. To address this, significant efforts have been made by investigators to develop pre-clinical models of SCLC allowing for downstream target identification in this difficult to treat cancer.Areas covered: In this review, we describe the current pre-clinical models that have been developed to interrogate SCLC, and outline the benefits and limitations associated with each. Using examples we show how each has been used to (i) improve our knowledge of this intractable cancer, and (ii) identify and validate potential therapeutic targets that (iii) are currently under development and testing within the clinic.Expert opinion: The large numbers of preclinical models that have been developed have dramatically improved the ways in which we can examine SCLC and test therapeutic targets/interventions. The newer models are rapidly providing novel avenues for the design and testing of new therapeutics. Despite this many of these models have inherent flaws that limit the possibility of their use for individualized therapy decision-making for SCLC.

The impact of smoking and the influence of other factors on lung cancer

Introduction: Smoking is the main preventable cause of lung cancer. This review summarizes preclinical and clinical data on the mechanisms of smoking-associated cancer development of the major histological lung cancer types small cell lung carcinoma squamous cell carcinoma and pulmonary adenocarcinoma (PAC) and the impact of several factors other than smoking on this process. Areas covered: The role of intracellular signaling induced by nicotinic receptors and beta-adrenergic receptors, the resulting increase in intracellular cyclic adenosine monophosphate (cAMP) as a key driver of PAC and the promoting effects of respiratory tract diseases and their therapeutics, psychological stress and global warming. Expert opinion: Smoking has deleterious effects on the regulation of lung epithelia by neurotransmitter receptors that are further enhanced by gene mutations. Sensitization of the alpha-7 nicotinic receptor (α7nAChR) by COPD enhances the carcinogenic effects of smoking and turns nicotine into a carcinogen. Nicotine vaping may, therefore, cause cancer in individuals with chronic obstructive pulmonary disease. The opposing effects of cAMP on the major lung cancer types indicate that patients with PAC of Clara cell phenotype (PAC-Cl) will benefit from treatment with cAMP reducers and suggest that global warming-induced respiratory tract diseases and their therapeutics cause the global increase in the incidence of PAC.

A gapmer antisense oligonucleotide targeting SRRM4 is a novel therapeutic medicine for lung cancer

Small cell lung cancer (SCLC) is the most aggressive neuroendocrine phenotype of the deadliest human lung cancers. However the therapeutic landscape for SCLC has not changed in over 30 years. Effective treatment and prognosis are needed to combat this aggressive cancer. Herein we report that Ser/Arg repetitive matrix 4 (SRRM4), a splicing activator, is abnormally expressed at high levels in SCLC and thus is a potential therapeutic target. We screened an effective gapmer antisense oligonucleotide (gASO) targeting SRRM4 in vitro which led to cell death of SCLC. Our gASO, which is stabilized by containing artificial nucleotides, effectively represses SRRM4 mRNA. We found that our gASO repressed SRRM4 synthesis leading to a dramatic tumor reduction in a lung cancer mouse model. We also analyzed miRNA microarray and found that the miR-4516 is abnormally increased in exosomes in the blood of SCLC patients. Treating with gASO suppressed tumors in the SCLC model mouse concurrently reduced plasma miR-4516. In conclusion this study reports that administration of an SRRM4-targeted gASO coupled with a novel miRNA diagnostic methodology represents a potential breakthrough in the therapeutic treatment of high mortality SCLC.

Establishment of a Novel PDX Mouse Model and Evaluation of the Tumor Suppression Efficacy of Bortezomib Against Liposarcoma

The patient-derived xenograft (PDX) model has been adopted as a major tool for studying tumorigenesis and differentiation in various carcinomas. In addition, it has been used in the development of anticancer agents. PDX models have been among the most meaningful tools used to understand the role of stromal cells and vascular cells in the body, which are major factors in cancer development and the application of therapeutic agents. Also, the establishment of PDX models from liposarcoma patients is considered to be important for understanding lipomagenesis and following drugs development. For these reasons, we developed patient-derived cell (PDC) and PDX models derived from 20 liposarcoma patients. The tissues of these patients were obtained in accordance with the principles of the Samsung Medical Center's ethics policy, and cell culture and xenografting onto the mice were performed under these principles. High-throughput drug screening (HTS) was carried out using established PDCs to select candidate drugs. Among the different candidate anticancer drugs, we tested the effect of bortezomib, which was expected to inhibit MDM2 amplification. First, we confirmed that the PDCs maintained the characteristics of liposarcoma cells by assessing MDM2 amplification and CDK4 overexpression using fluorescence in situ hybridization. Analysis of short tandem repeats and an array using comparative genomic hybridization confirmed that the PDX model exhibited the same genomic profile as that of the patient. Immunohistochemistry for MDM2 and CDK4 showed that the overexpression patterns of both proteins were similar in the PDX models and the PDCs. Specifically, MDM2 amplification was observed to be significantly correlated with the successful establishment of PDX mouse models. However, CDK4 expression did not show such a correlation. Of the anticancer drugs selected through HTS, bortezomib showed a strong anticancer effect against PDC. In addition, we observed that bortezomib suppressed MDM2 expression in a dose-dependent manner. In contrast, p21 tended to elicit an increase in PDC expression. Treatment of the PDX model with bortezomib resulted in an anticancer effect similar to that seen in the PDCs. These results support that PDCs and PDX models are among the most powerful tools for the development and clinical application of anticancer drugs for the treatment of liposarcoma patients.

Pre-clinical imaging for establishment and comparison of orthotopic non-small cell lung carcinoma: in search for models reflecting clinical scenarios

OBJECTIVE:

Clinically relevant animal models of non-small cell lung carcinoma (NSCLC) are required for the validation of novel treatments. We compared two different orthotopic transplantation techniques as well as imaging modalities to identify suitable mouse models mimicking clinical scenarios.

METHODS:

We used three genomically diverse NSCLC cell lines [National Cancer Institute (NCI)-H1703 adenosquamous cell carcinoma, NCI-H23 adenocarcinoma and A549 adenocarcinoma) for implanting tumour cells either as spheroids or cell suspension into lung parenchyma. Bioluminescence imaging (BLI) and contrast-enhanced cone beam CT (CBCT) were performed twice weekly to monitor tumour growth. Tumour histological data and microenvironmental parameters were determined.

RESULTS:

Tumour development after spheroid-based transplantation differs probably due to the integrity of spheroids, as H1703 developed single localised nodules, whereas H23 showed diffuse metastatic spread starting early after transplantation. A549 transplantation as cell suspension with the help of a stereotactic system was associated with initial single localised tumour growth and eventual metastatic spread. Imaging techniques were successfully applied to monitor longitudinal tumour growth: BLI revealed highly sensitive qualitative data, whereas CBCT was associated with less sensitive quantitative data. Histology revealed significant model-dependent heterogeneity in proliferation, hypoxia, perfusion and necrosis.

CONCLUSION:

Our developed orthotopic NSCLC tumours have similarity with biological growth behaviour comparable to that seen in the clinic and could therefore be used as attractive models to study tumour biology and evaluate new therapeutic strategies. The use of human cancer cell lines facilitates testing of different genomic tumour profiles that may affect treatment outcomes.

ADVANCES IN KNOWLEDGE:

The combination of different imaging modalities to identify tumour growth with subsequent use in treatment planning and orthotopic transplantation techniques to develop initially single lesions to ultimate metastases pave the way towards representative pre-clinical NSCLC models for experimental testing of novel therapeutic options in future studies.

Preparation, characterization, in vitro and in vivo anti-tumor effect of thalidomide nanoparticles on lung cancer

Introduction

Thalidomide (THA) is an angiogenesis inhibitor and an efficient inhibitor of the tumor necrosis factor-α (TNF-α). However, the clinical application of THA has been limited due to hydrophobicity of the compound.

Materials and methods

To increase the water solubility of THA and in order to evaluate the anticancer abilities of this material on human lung carcinoma, methoxy poly(ethylene glycol)-poly(ε-caprolactone) nanoparticles loaded with THA (THA-NPs) were prepared. The synthesis of THA-NPs was carried out via a dialysis method with relative satisfactory encapsulation efficiency, loading capacity, size distribution, and zeta potential.

Results

A cytotoxicity assay demonstrated that THA-NPs inhibited the growth of cells in a dose-dependent manner. The evaluation of anti-tumor activity in vivo showed that THA-NPs could inhibit tumor growth and prolong the survival rate of tumor-bearing mice. Immunohistochemical analysis indicated that THA-NPs inhibited cell proliferation (Ki-67 positive rate, 32.8%±4.2%, P<0.01), and resulted in a decreased rate of the tumor tissue microvessel density (3.87%±0.77%, P<0.01), VEGF (26.67%±4.02%, P<0.01), and TNF-α (75.21±6.85 ng/mL, P<0.01).

Conclusion

In general, the drug delivery system reported herein may shed light on future targeted therapy in lung cancer treatment.

CXCR4 antagonists suppress small cell lung cancer progression

Small cell lung cancer (SCLC) is an aggressive tumor with poor prognosis due to early metastatic spread and development of chemoresistance. Playing a key role in tumor-stroma interactions the CXCL12-CXCR4 axis may be involved in both processes and thus represent a promising therapeutic target in SCLC treatment. In this study we investigated the effect of CXCR4 inhibition on metastasis formation and chemoresistance using an orthotopic xenograft mouse model. This model demonstrates regional spread and spontaneous distant metastases closely reflecting the clinical situation in extensive SCLC. Tumor engraftment, growth, metabolism, and metastatic spread were monitored using different imaging techniques: Magnetic Resonance Imaging (MRI), Bioluminescence Imaging (BLI) and Positron Emission Tomography (PET). Treatment of mice bearing chemoresistant primary tumors with the specific CXCR4 inhibitor AMD3100 reduced the growth of the primary tumor by 61% (P<0.05) and additionally suppressed metastasis formation by 43%. In comparison to CXCR4 inhibition as a monotherapy, standard chemotherapy composed of cisplatin and etoposide reduced the growth of the primary tumor by 71% (P<0.01) but completely failed to suppress metastasis formation. Combination of chemotherapy and the CXCR4 inhibitor integrated the highest of both effects. The growth of the primary tumor was reduced to a similar extent as with chemotherapy alone and metastasis formation was reduced to a similar extent as with CXCR4 inhibitor alone. In conclusion, we demonstrate in this orthotopic mouse model that the addition of a CXCR4 inhibitor to chemotherapy significantly reduces metastasis formation. Thus, it might improve the overall therapy response and consequently the outcome of SCLC patients.

Proteasome inhibitor bortezomib enhances the effect of standard chemotherapy in small cell lung cancer

Small cell lung cancer (SCLC) is an aggressive cancer showing a very poor prognosis because of metastasis formation at an early stage and acquisition of chemoresistance. One key driver of chemoresistance is the transcription factor Forkhead box protein M1 (FOXM1) that regulates cell cycle proliferation, maintenance of genomic stability, DNA damage response, and cell differentiation in numerous tumor entities. In this study we investigated the role of FOXM1 in SCLC progression and analyzed the effect of FOXM1 inhibition using two proteasome inhibitors, bortezomib and siomycin A. FOXM1 was strongly expressed in patient-derived SCLC samples (n=123) and its nuclear localization was associated with the proliferation marker Ki-67. Both proteasome inhibitors successfully inhibited FOXM1 expression leading to a significantly reduced proliferation and a decreased mitotic rate along with cell cycle arrest and apoptosis induction. These effects were further enhanced by addition of bortezomib to standard chemotherapy. Treatment of mice bearing chemoresistant SCLC xenografts with bortezomib reduced the mean bioluminescence signal of tumors by 54%. Similarly, treatment with cisplatin as a standard chemotherapy reduced the mean bioluminescence signal of tumors by 58%. However, in combination with standard chemotherapy bortezomib further reduced the mean bioluminescence signal by 93% (p=0.0258). In conclusion, we demonstrate the effect of bortezomib in inhibiting FOXM1 expression and thus in sensitizing resistant SCLC cells to standard chemotherapy. Thus, addition of bortezomib to standard chemotherapy might potently improve SCLC therapy, particularly in an extensive cancer stage.

Mouse models of metastasis: progress and prospects

Metastasis is the spread of cancer cells from a primary tumor to distant sites within the body to establish secondary tumors. Although this is an inefficient process, the consequences are devastating as metastatic disease accounts for >90% of cancer-related deaths. The formation of metastases is the result of a series of events that allow cancer cells to escape from the primary site, survive in the lymphatic system or blood vessels, extravasate and grow at distant sites. The metastatic capacity of a tumor is determined by genetic and epigenetic changes within the cancer cells as well as contributions from cells in the tumor microenvironment. Mouse models have proven to be an important tool for unraveling the complex interactions involved in the metastatic cascade and delineating its many stages. Here, we critically appraise the strengths and weaknesses of the current mouse models and highlight the recent advances that have been made using these models in our understanding of metastasis. We also discuss the use of these models for testing potential therapies and the challenges associated with the translation of these findings into the provision of new and effective treatments for cancer patients.