Antitumour efficacy of the selumetinib and trametinib MEK inhibitors in a combined human airway-tumour-stroma lung cancer model

The role of extracellular vesicles in non-small-cell lung cancer, the unknowns, and how new approach methodologies can support new knowledge generation in the field

Extracellular vesicles (EVs) are nanosized particles released from most human cell types that contain a variety of cargos responsible for mediating cell-to-cell and organ-to-organ communications. Current knowledge demonstrates that EVs also play critical roles in many aspects of the progression of Non-Small-Cell Lung Cancer (NSCLC). Their roles range from increasing proliferative signalling to inhibiting apoptosis, promoting cancer metastasis, and modulating the tumour microenvironment to support cancer development. However, due to the limited availability of patient samples, intrinsic inter-species differences between human and animal EV biology, and the complex nature of EV interactions in vivo, where multiple cell types are present and several events occur simultaneously, the use of conventional preclinical and clinical models has significantly hindered reaching conclusive results. This review discusses the biological roles that EVs are currently known to play in NSCLC and identifies specific challenges in advancing today's knowledge. It also describes the NSCLC models that have been used to define currently-known EV functions, the limitations associated with their use in this field, and how New Approach Methodologies (NAMs), such as microfluidic platforms, organoids, and spheroids, can be used to overcome these limitations, effectively supporting future exciting discoveries in the NSCLC field and the potential clinical exploitation of EVs.

It is time to crowd your cell culture media - Physicochemical considerations with biological consequences

In vivo, the interior and exterior of cells is populated by various macromolecules that create an extremely crowded milieu. Yet again, in vitro eukaryotic cell culture is conducted in dilute culture media that hardly imitate the native tissue density. Herein, the concept of macromolecular crowding is discussed in both intracellular and extracellular context. Particular emphasis is given on how the physicochemical properties of the crowding molecules govern and determine kinetics, equilibria and mechanism of action of biochemical and biological reactions, processes and functions. It is evidenced that we are still at the beginning of appreciating, let alone effectively implementing, the potential of macromolecular crowding in permanently differentiated and stem cell culture systems.

Air-liquid interface cultures of the healthy and diseased human respiratory tract: promises, challenges and future directions

Air-liquid interface (ALI) culture models currently represent a valid instrument to recreate the typical aspects of the respiratory tract in vitro in both healthy and diseased state. They can help reducing the number of animal experiments, therefore, supporting the 3R principle. This review discusses ALI cultures and co-cultures derived from immortalized as well as primary cells, which are used to study the most common disorders of the respiratory tract, in terms of both pathophysiology and drug screening. The article displays ALI models used to simulate inflammatory lung diseases such as chronic obstructive pulmonary disease (COPD), asthma, cystic fibrosis, lung cancer, and viral infections. It also includes a focus on ALI cultures described in literature studying respiratory viruses such as SARS-CoV-2 causing the global Covid-19 pandemic at the time of writing this review. Additionally, commercially available models of ALI cultures are presented. Ultimately, the aim of this review is to provide a detailed overview of ALI models currently available and to critically discuss them in the context of the most prevalent diseases of the respiratory tract.

Bioinspired in vitro microenvironments to control cell fate: focus on macromolecular crowding

The development of therapeutic regenerative medicine and accurate drug discovery cell-based products requires effective, with respect to obtaining sufficient numbers of viable, proliferative, and functional cell populations, cell expansion ex vivo. Unfortunately, traditional cell culture systems fail to recapitulate the multifaceted tissue milieu in vitro, resulting in cell phenotypic drift, loss of functionality, senescence, and apoptosis. Substrate-, environment-, and media-induced approaches are under intense investigation as a means to maintain cell phenotype and function while in culture. In this context, herein, the potential of macromolecular crowding, a biophysical phenomenon with considerable biological consequences, is discussed.

Multiparametric investigation of non functionalized-AGuIX nanoparticles in 3D human airway epithelium models demonstrates preferential targeting of tumor cells

Liquid deposit mimicking surface aerosolization in the airway is a promising strategy for targeting bronchopulmonary tumors with reduced doses of nanoparticle (NPs). In mimicking and studying such delivery approaches, the use of human in vitro 3D culture models can bridge the gap between 2D cell culture and small animal investigations. Here, we exposed airway epithelia to liquid-apical gadolinium-based AGuIX^® NPs in order to determine their safety profile. We used a multiparametric methodology to investigate the NP’s distribution over time in both healthy and tumor-bearing 3D models. AGuIX^® NPs were able to target tumor cells in the absence of specific surface functionalization, without evidence of toxicity. Finally, we validated the therapeutic potential of this hybrid theranostic AGuIX^® NPs upon radiation exposure in this model. In conclusion, 3D cell cultures can efficiently mimic the normal and tumor-bearing airway epitheliums, providing an ethical and accessible model for the investigation of nebulized NPs.

Establishment and characterization of a cell line and patient-derived xenograft (PDX) from peritoneal metastasis of low-grade serous ovarian carcinoma

Peritoneal spread indicates poor prognosis in patients with serous ovarian carcinoma (SOC) and is generally treated by surgical cytoreduction and chemotherapy. Novel treatment options are urgently needed to improve patient outcome. Clinically relevant cell lines and patient-derived xenograft (PDX) models are of critical importance to therapeutic regimen evaluation. Here, a PDX model was established, by orthotopic engraftment after subperitoneal tumor slurry injection of low-grade SOC, resulting in an early-stage transplantable peritoneal metastasis (PM)-PDX model. Histology confirmed the micropapillary and cribriform growth pattern with intraluminal tumor budding and positivity for PAX8 and WT1. PM-PDX dissociated cells show an epithelial morphotype with a 42 h doubling time and 40% colony forming efficiency, they are low sensitive to platinum derivatives and highly sensitive to paclitaxel (IC50: 6.3 ± 2.2 nM, mean ± SEM). The patient primary tumor, PM, PM-PDX and derived cell line all show a KRAS c.35 G > T (p.(Gly12Val)) mutation and show sensitivity to the MEK inhibitor trametinib in vitro (IC50: 7.2 ± 0.5 nM, mean ± SEM) and in the PM mouse model. These preclinical models closely reflecting patient tumors are useful to further elucidate LGSOC disease progression, therapy response and resistance mechanisms.

A review of predictive, prognostic and diagnostic biomarkers for non-small-cell lung cancer: towards personalised and targeted cancer therapy

Introduction:

Lung cancer has a high mortality rate mainly due to the lack of early detection or outward signs and symptoms, thereby often progressing to advanced stages (e.g., stage IV) before it is diagnosed. However, if lung cancers can be diagnosed at an early stage and also if clinicians can prospectively identify patients likely to respond to specific treatments, then there is a very high potential to increase patients’ survival. In recent years, several investigations have been conducted to identify cancer biomarkers for lung cancer risk assessment, early detection and diagnosis, the likelihood of identifying the group of patients who will benefit from a particular treatment and monitoring patient response to treatment.

Materials and Methods:

This paper reports on the review of 19 current clinical and emerging biomarkers used in risk assessment, screening for early detection and diagnosis and monitoring the response of treatment of non-small-cell lung cancers.

Conclusion:

The future holds promise for personalised and targeted medicine from prevention, diagnosis to treatment, which take into account individual patient’s variability, though it depends on the development of effective biomarkers interrogating the key aberrant pathways and potentially targetable with molecular targeted or immunologic therapies. Lung cancer biomarkers have the potential to guide clinical decision-making since they can potentially detect the disease early, measure the risk of developing the disease and the risk of progression, provide accurate information of patient response to a specific treatment and are capable of informing clinicians about the likely outcome of a cancer diagnosis independent of the treatment received. Moreover, lung cancer biomarkers are increasingly linked to specific molecular pathway deregulations and/or cancer pathogenesis and can be used to justify the application of certain therapeutic or interventional strategies.

Mitogen-Activated Protein Kinase Pathway Inhibition for Redifferentiation of Radioiodine Refractory Differentiated Thyroid Cancer: An Evolving Protocol

Background: Some patients with metastatic differentiated thyroid cancer (DTC) lack iodine avidity and are therefore unsuitable for radioactive iodine (RAI) therapy. Limited experience suggests that single-agent selective mitogen-activated protein kinase (MAPK) pathway inhibitors can restore expression of the sodium-iodide symporter rendering RAI refractory (RAIR) DTC patients amenable to RAI therapy. The aim of this study was to assess the feasibility of mutation-guided MAPK-pathway blockade combined with thyroid hormone withdrawal (THW) for redifferentiation. Methods: This is a retrospective review of metastatic RAIR DTC and driver mutation in MAPK pathway, treated on a redifferentiation protocol. All patients had metastatic disease that had never been RAI-avid and/or imaging and biochemical progression despite treatment with RAI within the past 12 months. Patients with tumors harboring an NRAS mutation were treated with an MEK inhibitor (trametinib), and tumors with a BRAF^V600E mutation with combined BRAF and MEK inhibition (dabrafenib and trametinib; or vemurafenib and cobimetinib) for four weeks. Thyrotropin stimulation was performed by THW for four weeks. Restoration of RAI uptake was determined by ¹²⁴I positron emission tomography/computed tomography imaging. The response was assessed at least three months post-RAI. Results: From 2015 to 2017, six patients (age 45-70, four females) received redifferentiation therapy. Three patients had an NRAS mutation; two with follicular thyroid carcinoma (FTC) and one with a poorly differentiated thyroid carcinoma (PDTC); and three patients had a BRAF^V600E mutation and papillary thyroid carcinoma (PTC). One NRAS and all BRAF^V600E mutation cases demonstrated restoration of RAI uptake and proceeded to RAI therapy with a median follow-up of 16.6 months (range 13.5-42.3 months). The patient with an NRAS mutation and two of three patients with a BRAF^V600E demonstrated partial imaging response beyond a three-month follow-up. Grade 3 adverse events (acneiform rash) were observed in two patients with NRAS mutations. Conclusions: Mutation-guided MAPK pathway inhibition with MEK inhibitor or a combination of BRAF inhibitor and MEK inhibitor under concurrent THW is a feasible and a promising strategy to redifferentiate RAIR DTC, thereby rendering them suitable for RAI therapy with satisfactory retention following treatment.

ALI multilayered co-cultures mimic biochemical mechanisms of the cancer cell-fibroblast cross-talk involved in NSCLC MultiDrug Resistance

Background

Lung cancer is the leading cause of cancer-related deaths worldwide. This study focuses on its most common form, Non-Small-Cell Lung Cancer (NSCLC). No cure exists for advanced NSCLC, and patient prognosis is extremely poor. Efforts are currently being made to develop effective inhaled NSCLC therapies. However, at present, reliable preclinical models to support the development of inhaled anti-cancer drugs do not exist. This is due to the oversimplified nature of currently available in vitro models, and the significant interspecies differences between animals and humans.

Methods

We have recently established 3D Multilayered Cell Cultures (MCCs) of human NSCLC (A549) cells grown at the Air-Liquid Interface (ALI) as the first in vitro tool for screening the efficacy of inhaled anti-cancer drugs. Here, we present an improved in vitro model formed by growing A549 cells and human fibroblasts (MRC-5 cell line) as an ALI multilayered co-culture. The model was characterized over 14-day growth and tested for its response to four benchmarking chemotherapeutics.

Results

ALI multilayered co-cultures showed an increased resistance to the four drugs tested as compared to ALI multilayered mono-cultures. The signalling pathways involved in the culture MultiDrug Resistance (MDR) were influenced by the cancer cell-fibroblast cross-talk, which was mediated through TGF-β1 release and subsequent activation of the PI3K/AKT/mTOR pathway. As per in vivo conditions, when inhibiting mTOR phosphorylation, MDR was triggered by activation of the MEK/ERK pathway activation and up-regulation in cIAP-1/2 expression.

Conclusions

Our study opens new research avenues for the development of alternatives to animal-based inhalation studies, impacting the development of anti-NSCLC drugs.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-6038-x) contains supplementary material, which is available to authorized users.

From basic researches to new achievements in therapeutic strategies of KRAS-driven cancers

Among the numerous oncogenes involved in human cancers, KRAS represents the most studied and best characterized cancer-related genes. Several therapeutic strategies targeting oncogenic KRAS (KRAS onc ) signaling pathways have been suggested, including the inhibition of synthetic lethal interactions, direct inhibition of KRAS onc itself, blockade of downstream KRAS onc effectors, prevention of post-translational KRAS onc modifications, inhibition of the induced stem cell-like program, targeting of metabolic peculiarities, stimulation of the immune system, inhibition of inflammation, blockade of upstream signaling pathways, targeted RNA replacement, and oncogene-induced senescence. Despite intensive and continuous efforts, KRAS onc remains an elusive target for cancer therapy. To highlight the progress to date, this review covers a collection of studies on therapeutic strategies for KRAS published from 1995 to date. An overview of the path of progress from earlier to more recent insights highlight novel opportunities for clinical development towards KRASonc-signaling targeted therapeutics.

Health state dependent multiphoton induced autofluorescence in human 3D in vitro lung cancer model

Lung diseases pose the highest risk of death and lung cancer is a top killer among cancers with a mortality rate up to 70% within 1 year after diagnosis. Such a fast escalation of this cancer development makes early diagnosis and treatment a highly challenging task, and currently there are no effective tools to diagnose the disease at an early stage. The ability to discriminate between healthy and tumorous tissue has made autofluorescence bronchoscopy a promising tool for detection of lung cancer; however, specificity of this method remains insufficiently low. Here, we perform autofluorescence imaging of human lung cancer invading a human functional airway using an in vitro model of Non Small Cell Lung Cancer which combines a reconstituted human airway epithelium, human lung fibroblasts and lung adenocarcinoma cell lines, OncoCilAir™. By using two-photon laser induced autofluorescence microscopy combined with spectrally resolved imaging, we found that OncoCilAir™ provides tissue's health dependent autofluorescence similar as observed in lung tissue in patients. Moreover, we found spectral and intensity heterogeneity of autofluorescence at the edges of tumors. This metabolic related heterogeneity demonstrates ability of tumor to influence its microenvironment. Together, our result shows that OncoCilAir™ is a promising model for lung cancer research.

Establishment of a tumour-stroma airway model (OncoCilAir) to accelerate the development of human therapies against lung cancer

This paper highlights the work for which OncoTheis, a Swiss biotechnology company, engaged in the development of innovative bioengineered tissues and organoids for cancer research, was co-awarded the 2015 Lush Science Prize. Noting that the use of animal models failed to lead to the design of effective treatments for cancer, OncoTheis has opted to develop in vitro models based exclusively on human cells. The company currently focuses on lung cancer, which is the leading cause of cancer-related deaths worldwide, with more than one million deaths per year. To address this public health concern, we developed OncoCilAir™, a new 3-D model that mimics in vitro the progression of the disease as it happens in patients. In this system, bronchial and lung tumour cells obtained from discarded surgical tissue are cocultured in a Petri dish to reconstitute a fragment of the human lung. After appropriate differentiation, the culture closely reproduces malignant pulmonary nodules invading a small piece of functional airway tissue. As OncoCilAir includes both healthy and cancerous tissues, it can be used to test tumour-killing activity and the adverse effects of chemotherapies and other anti-cancer drugs. Moreover, a single culture can be maintained for up to three months, which permits studies of longer-term effects, including the assessment of drug resistance and tumour recurrence. OncoCilAir heralds a new generation of integrated in vitro models, which is expected to increase the quality of preclinical research while replacing animal testing.

KRAS AND THE REALITY OF PERSONALIZED MEDICINE IN NON-SMALL CELL LUNG CANCER

Lung cancer is the leading cause of mortality among all cancer types, worldwide. Latest available global statistics of World Health Organization report 1.59 million casualities in 2012 alone. Worldwide, 1 in 5 cancer deaths are caused by lung cancer. In 2016, in USA alone, estimated new cases of lung cancer are 224,390, of which 158,080 are expected to result in death as reported by National Cancer Institute. Non-small cell lung cancer (NSCLC), a histological subtype, comprises of about 85% of all cases, which is nearly 9 out of 10 lung cancer patients. Efforts are underway to develop and improve targeted therapy strategies. Certain mutations are being clinically targeted such as those in EGFR and ALK genes. However, one of the most frequently mutated genes in NSCLC is the KRAS oncogene, which is currently untargetable. Approximately 25% of all types of NSCLC tumors contain KRAS mutations, which remain as an undruggable challenge. These mutations are indicative of poor prognosis and confer negative response to standard chemotherapy. Furthermore, tumors harboring KRAS mutations are unlikely to respond to currently available targeted treatments such as Tyrosine Kinase Inhibitors. Therefore, there is a definitive, urgent need to generate new targeted therapy approaches for KRAS mutations. Current strategies have major limitations and evolve around targeting molecules upstream and downstream of KRAS. Direct targeting is not available in the clinic. Combination therapies of multiple agents are being sought. Concentrated efforts are needed to accelerate basic research and consecutive clinical trials to achieve effective targeting of KRAS.

Targeting the MEK signaling pathway in non-small cell lung cancer (NSCLC) patients with RAS aberrations

With the advancement in understanding the biology of non-small cell lung cancer (NSCLC), therapies focused on novel molecular pathways have come to the forefront of NSCLC treatment. This review focuses on the preclinical and clinical aspects underlying the targeting of RAS aberrations in NSCLC with special focus on MEK inhibitors which work by inhibiting the principal downstream mediator of RAS aberrations with a view on how to optimize outcomes with these agents. Preclinical evidence of the activity of MEK inhibitors in KRAS-mutant NSCLC has pushed forward the clinical development of these agents (namely selumetinib and trametinib) in KRAS-mutant NSCLC particularly in combination with other agents. A number of randomized studies have been launched to confirm the activity of these agents and to establish their position in the treatment armamentarium of NSCLC.