Small cell and non small cell lung cancer form metastasis on cellular 4D lung model

Using ex vivo bioengineered lungs to model pathologies and screening therapeutics: A proof-of-concept study

Respiratory diseases, claim over eight million lives annually. However, the transition from preclinical to clinical phases in research studies is often hindered, partly due to inadequate representation of preclinical models in clinical trials. To address this, we conducted a proof-of-concept study using an ex vivo model to identify lung pathologies and to screen therapeutics in a humanized rodent model. We extracted and decellularized mouse heart-lung tissues using a detergent-based technique. The lungs were then seeded and cultured with human cell lines (BEAS-2B, A549, and Calu3) for 6-10 days, representing healthy lungs, cancerous states, and congenital pathologies, respectively. By manipulating cultural conditions and leveraging the unique characteristics of the cell lines, we successfully modeled various pathologies, including advanced-stage solid tumors and the primary phase of SARS-CoV-2 infection. Validation was conducted through histology, immunofluorescence staining, and pathology analysis. Additionally, our study involved pathological screening of the efficacy and impact of key anti-neoplastic therapeutics (Cisplatin and Wogonin) in cancer models. The results highlight the versatility and strength of the ex vivo model in representing crucial lung pathologies and screening therapeutics during the preclinical phase. This approach holds promise for bridging the gap between preclinical and clinical research, aiding in the development of effective treatments for respiratory diseases, including lung cancer.

Design, Synthesis, Antitumor Activity and NMR-Based Metabolomics of Novel Amino Substituted Tetracyclic Imidazo[4,5-b]Pyridine Derivatives

Newly prepared tetracyclic imidazo[4,5-b]pyridine derivatives were synthesized to study their antiproliferative activity against human cancer cells. Additionally, the structure-activity was studied to confirm the impact of the N atom position in pyridine nuclei as well as the chosen amino side chains on antiproliferative activity. Targeted amino substituted regioisomers were prepared by using uncatalyzed amination from corresponding chloro substituted precursors. The most active compounds 6 a, 8 and 10 showed improved activity in comparison to standard drug etoposide with IC50 values in a nanomolar range of concentration (0.2-0.9 μM). NMR-based metabolomics is a powerful instrument to elucidate activity mechanism of new chemotherapeutics. Multivariate and univariate statistical analysis of metabolic profiles of non-small cell lung cancer cells before and after exposure to 6 a revealed significant changes in metabolism of essential amino acids, glycerophospholipids and oxidative defense. Insight into the changes of metabolic pathways that are heavily involved in cell proliferation and survival provide valuable guidelines for more detailed analysis of activity metabolism and possible targets of this class of bioactive compounds.

AMPK activation reduces cancer cell aggressiveness via inhibition of monoamine oxidase A (MAO-A) expression/activity

AIM

AMPK can be considered as an important target molecule for cancer for its unique ability to directly recognize cellular energy status. The main aim of this study is to explore the role of different AMPK activators in managing cancer cell aggressiveness and to understand the mechanistic details behind the process.

MAIN METHODS

First, we explored the AMPK expression pattern and its significance in different subtypes of lung cancer by accessing the TCGA data sets for LUNG, LUAD and LUSC patients and then established the correlation between AMPK expression pattern and overall survival of lung cancer patients using Kaplan-Meire plot. We further carried out several cell-based assays by employing different wet lab techniques including RT-PCR, Western Blot, proliferation, migration and invasion assays to fulfil the aim of the study.

KEY FINDINGS

SIGNIFICANCE: This study identifies the importance of AMPK activators as a repurposing agent for combating lung and colon cancer cell aggressiveness. It also suggests SRT-1720 as a potent repurposing agent for cancer treatment especially in NSCLC patients where a point mutation is present in LKB1.

PP2A B55α inhibits epithelial-mesenchymal transition via regulation of Slug expression in non-small cell lung cancer

PP2A B55α, encoded by PPP2R2A, acts as a regulatory subunit of the serine/threonine phosphatase PP2A. Despite a frequent loss of heterozygosity of PPP2R2A in cases of non-small cell lung cancer (NSCLC), research on PP2A B55α's functions remains limited and controversial. To investigate the biological roles of PP2A B55α, we conducted bulk RNA-sequencing to assess the impact of PPP2R2A knockdown using two shRNAs in a NSCLC cell line. Gene set enrichment analysis (GSEA) of the RNA-sequencing data revealed significant enrichment of the epithelial-mesenchymal transition (EMT) pathway, with SNAI2 (the gene encoding Slug) emerging as one of the top candidates. Our findings demonstrate that PP2A B55α suppresses EMT, as PPP2R2A deficiency through knockdown or homozygous or hemizygous depletion promotes EMT and metastatic behavior in NSCLC cells, as evidenced by changes in EMT biomarkers, invasion and migration abilities, as well as metastasis in a tail vein assay. Mechanistically, PP2A B55α inhibits EMT by downregulating SNAI2 expression via the GSK3β-β-catenin pathway. Importantly, PPP2R2A deficiency also slows cell proliferation by disrupting DNA replication, particularly in PPP2R2A-/- cells. Furthermore, PPP2R2A deficiency, especially PPP2R2A-/- cells, leads to an increase in the cancer stem cell population, which correlates with enhanced resistance to chemotherapy. Overall, the decrease in PP2A B55α levels due to hemizygous/homozygous depletion heightens EMT and the metastatic or stemness/drug resistance potential of NSCLC cells despite their proliferation disadvantage. Our study highlights the significance of PP2A B55α in EMT and metastasis and suggests that targeting EMT/stemness could be a potential therapeutic strategy for treating PPP2R2A-deficient NSCLC.

Correlation between biological and mechanical properties of extracellular matrix from colorectal peritoneal metastases in human tissues

Peritoneal metastases (PM) are common routes of dissemination for colorectal cancer (CRC) and remain a lethal disease with a poor prognosis. The properties of the extracellular matrix (ECM) are important in cancer development; studying their changes is crucial to understand CRC-PM development. We studied the elastic properties of ECMs derived from human samples of normal and neoplastic PM by atomic force microscopy (AFM); results were correlated with patient clinical data and expression of ECM components related to metastatic spread. We show that PM progression is accompanied by stiffening of the ECM, increased cancer associated fibroblasts (CAF) activity and increased deposition and crosslinking in neoplastic matrices; on the other hand, softer regions are also found in neoplastic ECMs on the same scales. Our results support the hypothesis that local changes in the normal ECM can create the ground for growth and spread from the tumour of invading metastatic cells. We have found correlations between the mechanical properties (relative stiffening between normal and neoplastic ECM) of the ECM and patients' clinical data, like age, sex, presence of protein activating mutations in BRAF and KRAS genes and tumour grade. Our findings suggest that the mechanical phenotyping of PM-ECM has the potential to predict tumour development.

Polypeptide Bilayer Assembly-Mediated Gene Delivery Enhances Chemotherapy in Cancer Cells

Developing gene vectors with high transfection efficiency and low cytotoxicity to humans is crucial to improve gene therapy outcomes. This study set out to investigate the use of cationic polypeptide bilayer assemblies formed by coil-sheet poly(l-lysine)-block-poly(l-benzyl-cysteine) (PLL-b-PBLC) as gene vectors that present improved transfection efficiency, endosomal escape, and biocompatibility compared to PLL. The formation of the polyplexes was triggered by hydrogen bonding, hydrophobic interactions, and electrostatic association between the cationic PLL segments and the negatively charged plasmid encoding p53, resulting in self-assembled polypeptide chains. Transfection efficiency of these polyplexes increased with increments of PLL-to-PBLC block ratios, with PLL₁₅-b-PBLC₅ bilayers exhibiting the best in vitro transfection efficiency among all, suggesting that PLL-b-PBLC bilayer assemblies are efficient in the protection and stabilization of genes. The polypeptide bilayer gene vector reversed the cisplatin sensitivity of p53-null cancer cells by increasing apoptotic signaling. Consistent with in vitro results, mouse xenograft studies revealed that PLL₁₅-b-PBLC₅/plasmid encoding p53 therapy significantly suppressed tumor growth and enhanced low-dose cisplatin treatment, while extending survival of tumor-bearing mice and avoiding significant body weight loss. This study presents a feasible gene therapy that, combined with low-dose chemotherapeutic drugs, may treat genetically resistant cancers while reducing side effects in clinical patients.

Elucidating cell surface glycan imbalance through SERS guided metabolic glycan labelling: An appraisal of metastatic potential in cancer cells

The intrinsic complexities of cell-surface glycans impede tracking the metabolic changes in cells. By coupling metabolic glycan labelling (MGL) and surface-enhanced Raman scattering (SERS), we employed the MGL-SERS strategy to elucidate the differential glycosylation pattern in cancer cell lines. Herein, for the first time, we are reporting an N-alkyl derivative of glucosamine (GlcNPhAlk) as a glycan labelling precursor. The extent of labelling was assessed by utilizing Raman imaging and verified by complementary fluorescence and Western blot analysis. MGL-SERS technique was implemented for a comparative evaluation of cell surface glycan imbalance in different cancer cells wherein a linear relationship between glycan expression and metastatic potential was established. Further, the effect of sialyltransferase inhibitor, P-3Fax-Neu5Ac, on metabolic labelling of GlcNPhAlk proved the incorporation of GlcNPhAlk to the terminal glycans through the sialic acid biosynthetic pathway. Hence, this methodology unveils the phenomenon of metastatic progression in cancer cells with inherent glycosylation-related dysplasia.

The microRNA-520a-3p inhibits invasion and metastasis by targeting NF-kappaB signaling pathway in non-small cell lung cancer

PURPOSE

To identify the expression of miR-520a-3p and AKT1 in non-small cell lung cancer cells (NSCLC) and the mechanism in inhibiting cell invasion and metastasis by targeting NF-kappaB signaling pathway.

METHODS

Bioinformatics analysis and dual luciferase reporter gene assay were used to predict and verify the targeting relationship between miR-520a-3p and AKT1. EdU assay was used to detect the proliferation of NSCLC cells. Flow cytometry detected the apoptosis of NSCLC cells. Transwell assay tested the invasion ability of NSCLC cells. qRT-PCR measured the expression of miR-520a-3p and AKT1 mRNA in NSCLC cells; while western blotting was adopted to detect the protein expressions of AKT1, Ki67, CyclinD1, Bax, Bcl-2, MMP-2, MMP-9, NF-kB p65, IkBs kinase (IKK), NF-kB inducing kinase (NIK).

RESULTS

Bioinformatics analysis suggested that miR-520a-3p could target AKT1. miR-520a-3p could regulate the expression of AKT1 negatively. Compared to mimic-NC group, miR-520a-3p mimic group had increased expressions of miR-520a-3p and Bax, while decreased expressions of AKT1, Ki67, CyclinD1, Bcl-2, MMP-2, MMP-9, NF-kB p65, IKK and NIK, reduced cell proliferation, invasion, and increased cell apoptosis rate (all P < 0.05). Compared to inhibitor NC group, miR-520a-3p inhibitor group had decreased expressions of miR-520a-3p and Bax, but increased expressions of AKT1, Ki67, CyclinD1, Bcl-2, MMP-2, MMP-9, NF-kB p65, IKK and NIK, promoted cell proliferation, invasion, and suppressed cell apoptosis rate (all P < 0.05).

CONCLUSION

Overexpression of miR-520a-3p can target and downregulate the expression of AKT1 to inhibit the invasion and metastasis of NSCLC via suppressing the activation of NF-kappaB signaling pathway.

MicroRNA (miR)-355 Suppressed Small Cell Lung Cancer Cell Metastasis via Regulating P38 Mitogen-Activated Protein Kinases (MAPKs) Signaling

MicroRNA (miR)-355 was reported to mediate p38 mitogen-activated protein kinases (MAPKs) signaling, which exerted an effect on cell invasion and metastasis. But whether miR-355 could inhibit small cell lung cancer cell line H446 cell metastasis by regulating p38 MAPKs signaling needs further study. H446 cells were cultured to establish miR-355 overexpression group and blank group. The expression of MT1-MMP, the activity and migration of H446 cells were evaluated. Further, the ability of invasion, the level of p-p38 MAPKs and the activity degree of MT1-MMP were observed in H446 cells. MT1-MMP was mainly expressed on the cell membrane. miR-355 overexpression significantly decreased cellular viability and reduced MT1-MMP and p-p38 MAPKs levels relative to the blank group without influencing p38 MAPKs level. In addition, miR-355 overexpression suppressed cell migration and invasive ability in H446 cells. Finally, miR-355 overexpression reduced pro-MMP and MMP-2 activity in H446 cells. miR-355 overexpression suppressed H446 cell metastasis through regulating P38 MAPKs signaling.

Hiltonol Cocktail Kills Lung Cancer Cells by Activating Cancer-Suppressors, PKR/OAS, and Restraining the Tumor Microenvironment

NSCLC (non-small cell lung cancer) is a leading cause of cancer-related deaths worldwide. Clinical trials showed that Hiltonol, a stable dsRNA representing an advanced form of polyI:C (polyinosinic-polycytidilic acid), is an adjuvant cancer-immunomodulator. However, its mechanisms of action and effect on lung cancer have not been explored pre-clinically. Here, we examined, for the first time, how a novel Hiltonol cocktail kills NSCLC cells. By retrospective analysis of NSCLC patient tissues obtained from the tumor biobank; pre-clinical studies with Hiltonol alone or Hiltonol⁺⁺⁺ cocktail [Hiltonol+anti-IL6+AG490 (JAK2 inhibitor)+Stattic (STAT3 inhibitor)]; cytokine analysis; gene knockdown and gain/loss-of-function studies, we uncovered the mechanisms of action of Hiltonol⁺⁺⁺. We demonstrated that Hiltonol⁺⁺⁺ kills the cancer cells and suppresses the metastatic potential of NSCLC through: (i) upregulation of pro-apoptotic Caspase-9 and Caspase-3, (ii) induction of cytosolic cytochrome c, (iii) modulation of pro-inflammatory cytokines (GRO, MCP-1, IL-8, and IL-6) and anticancer IL-24 in NSCLC subtypes, and (iv) upregulation of tumor suppressors, PKR (protein kinase R) and OAS (2′5′ oligoadenylate synthetase). In silico analysis showed that Lys296 of PKR and Lys66 of OAS interact with Hiltonol. These Lys residues are purportedly involved in the catalytic/signaling activity of the tumor suppressors. Furthermore, knockdown of PKR/OAS abrogated the anticancer action of Hiltonol, provoking survival of cancer cells. Ex vivo analysis of NSCLC patient tissues corroborated that loss of PKR and OAS is associated with cancer advancement. Altogether, our findings unraveled the significance of studying tumor biobank tissues, which suggests PKR and OAS as precision oncological suppressor candidates to be targeted by this novel Hiltonol⁺⁺⁺ cocktail which represents a prospective drug for development into a potent and tailored therapy for NSCLC subtypes.

Decellularized Extracellular Matrix for Bioengineering Physiomimetic 3D in Vitro Tumor Models

Recent advances in the extraction and purification of decellularized extracellular matrix (dECM) obtained from healthy or malignant tissues open new avenues for engineering physiomimetic 3D in vitro tumor models, which closely recapitulate key biomolecular hallmarks and the dynamic cancer cell-ECM interactions in the tumor microenvironment. We review current and upcoming methodologies for chemical modification of dECM-based biomaterials and advanced bioprocessing into organotypic 3D solid tumor models. A comprehensive review of disruptive advances and shortcomings of exploring dECM-based biomaterials for recapitulating the native tumor-supporting matrix is also provided. We hope to drive the discussion on how 3D dECM testing platforms can be leveraged for generating microphysiological tumor surrogates that generate more robust and predictive data on therapeutic bioperformance.

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.

Immune cells inhibit the tumor metastasis in the 4D cellular lung model by reducing the number of live circulating tumor cells

The immune system and tumor microenvironment play a decisive role in tumor progression. We developed a novel model to better understand tumor progression and interaction with immune cells and the cellular components. We grew 393 P non-metastatic and 344SQ metastatic murine cells in an acellular metastatic lung cancer model, where both cell lines formed circulating tumor cells (CTC) and metastatic lesions. When the CTC from this model were placed in the tail vein of nu/nu mice, both cell lines formed metastatic lesions. However, in syngeneic immune-competent mice, the CTC from the non-metastatic cell line did not metastasize while the CTC from the metastatic cell line metastasized. When we placed the activated immune cells in the cellular lung model, it decreased CTC and metastatic lesion formation for the non-metastatic cell line while it had no impact on metastatic cell line. The metastatic cell line had a significant increase in expression of programmed death-ligand 1 (PDL-1) compared to the non-metastatic cell line in the model. Overall, the immune cells showed an impact on viability of CTC for cell lines with a decreased expression of PDL-1 that leads to decreased metastatic lesion formation. Further studies are needed to understand the subtype of immune cells and mechanism of decreased CTC viability and metastasis inhibition.

Withaferin A inhibits Epithelial to Mesenchymal Transition in Non-Small Cell Lung Cancer Cells

Lung cancer is the leading cause of cancer-related deaths worldwide and in the United States. Despite recent advancements in treatment approaches, metastasis remains a major therapeutic challenge in lung cancer and explains the extremely poor prognosis. Epithelial to mesenchymal transition (EMT), a complex process of cellular reprogramming has become an attractive drug target because it plays a crucial role in the metastasis of non-small cell lung cancer (NSCLC). In the present study, we examined the effects of withaferin A (WFA), a plant-derived steroidal lactone on EMT in human NSCLC cell lines. First, we demonstrated that WFA displayed time- and concentration-dependent cytotoxicity on A549 and H1299 NSCLC cells. Then, cells were exposed to ≤ 0.5 µM WFA for ≤ 4 h to minimize cytotoxicity and determined its effects on EMT, cell adhesion, motility, migration, and invasion. EMT induction was performed by culturing cells in serum-free media containing TGFβ1 (5 ng/mL) and TNFα (25 ng/mL) for 48 h. We observed that pretreatment of cells with WFA inhibited cell adhesion, migration, and invasion of A549 and H1299 cells. Using western blot, immunofluorescence, and qRT-PCR analysis, we demonstrated that WFA suppressed TGFβ1 and TNFα-induced EMT in both cell lines. Mechanistically, WFA suppressed the phosphorylation and nuclear translocation of Smad2/3 and NF-κB in A549 and H1299 cells. Together, our study provides additional evidence demonstrating the inhibitory effects of WFA on EMT induction in NSCLC cells and further demonstrates the therapeutic potential of WFA against the metastasis in NSCLC.

Acellular and Cellular Lung Model to Study Tumor Metastasis

It is difficult to isolate tumor cells at different points of tumor progression. We created an ex vivo lung model that can show the interaction of tumor cells with a natural matrix and continual flow of nutrients, as well as a model that shows the interaction of tumor cells with normal cellular components and a natural matrix. The acellular ex vivo lung model is created by isolating a rat heart-lung block and removing all the cells using the decellularization process. The right main bronchus is tied off and tumor cells are placed in the trachea by a syringe. The cells move and populate the left lung. The lung is then placed in a bioreactor where the pulmonary artery receives a continual flow of media in a closed circuit. The tumor grown on the left lung is the primary tumor. The tumor cells that are isolated in the circulating media are circulating tumor cells and the tumor cells in the right lung are metastatic lesions. The cellular ex vivo lung model is created by skipping the decellularization process. Each model can be used to answer different research questions.

The Prognostic Role of Circulating Tumor Cells (CTCs) in Lung Cancer

Lung cancer affects over 1. 8 million people worldwide and is the leading cause of cancer related mortality globally. Currently, diagnosis of lung cancer involves a combination of imaging and invasive biopsies to confirm histopathology. Non-invasive diagnostic techniques under investigation include "liquid biopsies" through a simple blood draw to develop predictive and prognostic biomarkers. A better understanding of circulating tumor cell (CTC) dissemination mechanisms offers promising potential for the development of techniques to assist in the diagnosis of lung cancer. Enumeration and characterization of CTCs has the potential to act as a prognostic biomarker and to identify novel drug targets for a precision medicine approach to lung cancer care. This review will focus on the current status of CTCs and their potential diagnostic and prognostic utility in this setting.

The use of decellularised animal tissue to study disseminating cancer cells

Since the establishment of cell culture, common practice has been to grow adherent cells in 2D monolayers. Although cells behave completely differently when grown in these artificial conditions, the ease of 2D culturing has meant that this practice still prevails today, and adopting conditions that more closely reflect the natural microenvironment has been met with substantial inertia. The alternative, animal models that mimic natural human physiology, are less accessible, strictly regulated and require licences and expensive facilities. Although transition from 2D to 3D cell culturing is gathering momentum, there is a clear need for alternative culturing methods that more closely resemble in vivo conditions. Here we show that decellularised organs gleaned from discarded animal carcasses are ideal biomimetic scaffolds to support secondary tumour initiation in vitro. This article describes how to decellularise tissue, perform basic histochemistry and immunofluorescence procedures for cell and matrix detection; and follows cancer cell behaviour on this matrix by way of an example. As integration into the traditional work flow is easy and inexpensive we hope this article will encourage other researchers to adopt this approach.