Novel platinum agents and mesenchymal stromal cells for thoracic malignancies: state of the art and future perspectives

Advances in Understanding the Roles of Mesenchymal Stem Cells in Lung Cancer

Lung cancer is the most common and deadliest type of cancer worldwide. Research concerning lung cancer has made considerable progress in recent decades, but lung cancer remains the leading cause of malignancy-related mortality rate. Mesenchymal stem cells (MSCs) mainly exist in fat, umbilical cord blood, bone marrow, bone, and muscle. MSCs are a primary component of the tumor microenvironment (TME). Recent studies have shown that MSCs have roles in lung cancer-related proliferation, invasion, migration, and angiogenesis, but the underlying mechanisms are poorly understood. Because MSCs can migrate to the TME, there is increasing attention toward the use of MSCs in drugs or gene vectors for cancer treatment. This review summarizes the roles and effects of MSCs in lung cancer, while addressing clinical applications of MSCs in lung cancer treatment.

7-T MRI tracking of mesenchymal stromal cells after lung injection in a rat model

Background

Mesenchymal stromal cells (MSCs) are able to migrate and engraft at sites of inflammation, injuries, and tumours, but little is known about their fate after local injection. The purpose of this study is to perform MSC tracking, combining in vivo 7-T magnetic resonance imaging (MRI) and histological assessment, following lung injection in a rat model.

Methods

Five lungs were injected with ferumoxide-labelled MSCs and five with perfluorocarbon-labelled MSCs and underwent 7-T MRI. MRI acquisitions were recorded immediately (T₀), at 24 h (T₂₄) and/or 48 h (T₄₈) after injection. For each rat, labelled cells were assessed in the main organs by MRI. Target organs were harvested under sterile conditions from rats sacrificed 0, 24, or 48 h after injection and fixed for histological analysis via confocal and structured illumination microscopy.

Results

Ferumoxide-labelled MSCs were not detectable in the lungs, whereas they were not visible in the distant sites. Perfluorocarbon-labelled MSCs were seen in 5/5 injected lungs at T₀, in 1/2 at T₂₄, and in 1/3 at T₄₈. The fluorine signal in the liver was seen in 3/5 at T₀, in 1/2 at T24, and in 2/3 at T₄₈. Post-mortem histology confirmed the presence of MSCs in the injected lung.

Conclusions

Ferumoxide-labelled cells were not seen at distant sites; a linear decay of injected perfluorocarbon-labelled MSCs was observed at T₀, T₂₄, and T₄₈ in the lung. In more than half of the experiments, perfluorocarbon-labelled MSCs scattering to the liver was observed, with a similar decay over time as observed in the lung.

The therapeutic potential of mesenchymal stem cells in lung cancer: benefits, risks and challenges

BACKGROUND

Lung cancer is one of the most challenging diseases to treat. In the past decades standard therapy including surgery, chemo- and radiation therapy, alone or in combination has not changed the high mortality rate and poor prognosis. In recent years, mesenchymal stem cells (MSCs) have emerged as putative therapeutic tools due to their intrinsic tumor tropism, anti-tumor and immunoregulatory properties. MSCs release biomolecules that are thought to exert the same beneficial effects as their cellular counterparts and, as such, they may offer practical possibilities of using MSC-secreted products. Owing to their innate affinity to home to tumor sites, MSCs have also gained interest as selective vehicles for the delivery of anti-cancer agents. However, MSCs are also known to confer pro-oncogenic effects, rendering them into double-sword weapons against neoplastic diseases.

CONCLUSIONS

Here, we present published data on the cell- and secretome-based therapeutic competences of MSCs, as well as on their potential as engineered delivery vectors for the treatment of lung cancer. Despite the controversial role of MSCs in the context of lung cancer therapy, current findings support hopeful perspectives to harness the potential of MSC-based regimens that may augment current treatment modalities in lung cancer.