Nestin-Expressing Cells in the Lung: The Bad and the Good Parts

The expression of intermediate filaments in the abomasum of ruminants: A comparative study

Intermediate filaments (IFs) are key molecular factors of the cell and have been reported to play an important role in maintaining the structural integrity and functionality of the abomasum. This study was designed to determine the regional distribution, cellular localization and expression of several IFs, including CK8, CK18, CK19, vimentin, desmin, peripherin and nestin, as well as the connective tissue component laminin, in the bovine, ovine and caprine abomasa. Immunohistochemical analyses demonstrated varying levels of expression of CK8, CK18, CK19, vimentin, desmin, nestin, peripherin and laminin in the bovine, ovine and caprine abomasa. CK8 immunoreactions were particularly evident in the luminal and glandular epithelia of the glands found in the abomasal cardia, fundus and pylorus in all three species. In the bovine abomasum, CK18 immunoreactions were stronger in the parietal cells, compared to the chief cells. In the abomasum of all three species, the smooth muscle as well as the smooth muscle cells of the vascular media in the cardiac, fundic and pyloric regions showed strong immunoreactivity. In all three species, the cardiac, fundic and pyloric regions of the abomasum showed strong peripherin and nestin immunoreactions in the luminal and glandular epithelial cells, stromal and smooth muscle cells, nervous plexuses and blood vessels. The expression patterns of IFs and laminin in the ruminant abomasum suggest that these proteins play a structural role in the cytoskeleton and are effective in maintaining abomasal tissue integrity and stability.

Distribution, contribution and regulation of nestin+ cells

BACKGROUND

Nestin is an intermediate filament first reported in neuroepithelial stem cells. Nestin expression could be found in a variety of tissues throughout all systems of the body, especially during tissue development and tissue regeneration processes.

AIM OF REVIEW

This review aimed to summarize and discuss current studies on the distribution, contribution and regulation of nestin+ cells in different systems of the body, to discuss the feasibility ofusing nestin as a marker of multilineage stem/progenitor cells, and better understand the potential roles of nestin+ cells in tissue development, regeneration and pathological processes.

KEY SCIENTIFIC CONCEPTS OF REVIEW

This review highlights the potential of nestin as a marker of multilineage stem/progenitor cells, and as a key factor in tissue development and tissue regeneration. The article discussed the current findings, limitations, and potential clinical implications or applications of nestin+ cells. Additionally, it included the relationship of nestin+ cells to other cell populations. We propose potential future research directions to encourage further investigation in the field.

A novel risk signature for predicting brain metastasis in patients with lung adenocarcinoma

BACKGROUND

Brain metastasis (BM) are a devastating consequence of lung cancer. This study was aimed to screen risk factors for predicting BM.

METHODS

Using an in vivo BM preclinical model, we established a series of lung adenocarcinoma (LUAD) cell subpopulations with different metastatic ability. Quantitative proteomics analysis was used to screen and identify the differential protein expressing map among subpopulation cells. Q-PCR and Western-blot were used to validate the differential proteins in vitro. The candidate proteins were measured in LUAD tissue samples (n = 81) and validated in an independent TMA cohort (n = 64). A nomogram establishment was undertaken by performing multivariate logistic regression analysis.

RESULTS

The quantitative proteomics analysis, qPCR and Western blot assay implied a five-gene signature that might be key proteins associated with BM. In multivariate analysis, the occurrence of BM was associated with age ≤ 65 years, high expressions of NES and ALDH6A1. The nomogram showed an area under the receiver operating characteristic curve (AUC) of 0.934 (95% CI, 0.881-0.988) in the training set. The validation set showed a good discrimination with an AUC of 0.719 (95% CI, 0.595-0.843).

CONCLUSIONS

We have established a tool that is able to predict occurrence of BM in LUAD patients. Our model based on both clinical information and protein biomarkers will help to screen patient in high-risk population of BM, so as to facilitate preventive intervention in this part of the population.

Immune Privileges as a Result of Mutual Regulation of Immune and Stem Systems

Immune privileges of cancer stem cells is a well-known and widely studied problem, as presence of such cells in tumors is associated with refractoriness, recurrence, and metastasis. Accumulating evidence also suggests presence of immune privileges in non-pathological stem cells in addition to their other defense mechanisms against damaging factors. This similarity between pathological and normal stem cells raises the question of why stem cells have such a potentially dangerous property. Regulation of vital processes of autoimmunity control and regeneration realized through interactions between immune cells, stem cells, and their microenvironment are reviewed in this work as causes of formation of the stem cell immune privilege. Deep mutual integration between regulations of stem and immune cells is noted. Considering diversity and complexity of mutual regulation of stem cells, their microenvironment, and immune system, I suggest the term "stem system".

Nestin and Notch3 collaboratively regulate angiogenesis, collagen production, and endothelial-mesenchymal transition in lung endothelial cells

BACKGROUND

Nestin, an intermediate filament protein, participates in various pathophysiological processes, including wound healing, angiogenesis, endothelial-mesenchymal transition (EndoMT), and fibrosis. However, the pathophysiological roles of lung nestin-expressing cells remain unclear due to conflicting reports. The objective of this study is to elucidate the characteristics and functions of lung nestin-expressing cells.

METHODS

We conducted a series of in vitro and in vivo experiments using endothelial cell line MS1 and nestin-GFP mice. This animal model allows for nestin-expressing cell detection without the use of anti-nestin antibodies.

RESULTS

Lung nestin-expressing cells occurred in approximately 0.2% of CD45- cells and was co-expressed with epithelial, endothelial, and mesenchymal cell-surface markers. Importantly, virtually all nestin-expressing cells co-expressed CD31. When compared to lung nestin-nonexpressing endothelial cells, nestin-expressing endothelial cells showed robust angiogenesis with frequent co-expression of PDGFRβ and VEGFR2. During TGFβ-mediated EndoMT, the elevation of Nes mRNA expression preceded that of Col1a1 mRNA, and nestin gene silencing using nestin siRNA resulted in further upregulation of Col1a1 mRNA expression. Furthermore, Notch3 expression was regulated by nestin in vitro and in vivo; nestin siRNA resulted in reduced Notch3 expression accompanied with enhanced EndoMT. Contrary to previous reports, neither Nes mRNA expression nor nestin-expressing cells were increased during pulmonary fibrosis.

CONCLUSIONS

Our study showed that (1) lung nestin-expressing cells are an endothelial lineage but are distinct from nestin-nonexpressing endothelial cells; (2) nestin regulates Notch3 and they act collaboratively to regulate angiogenesis, collagen production, and EndoMT; and (3) nestin plays novel roles in lung angiogenesis and fibrosis. Video Abstract.

Back to the Basics: Usefulness of Naturally Aged Mouse Models and Immunohistochemical and Quantitative Morphologic Methods in Studying Mechanisms of Lung Aging and Associated Diseases

Aging-related molecular and cellular alterations in the lung contribute to an increased susceptibility of the elderly to devastating diseases. Although the study of the aging process in the lung may benefit from the use of genetically modified mouse models and omics techniques, these approaches are still not available to most researchers and produce complex results. In this article, we review works that used naturally aged mouse models, together with immunohistochemistry (IHC) and quantitative morphologic (QM) methods in the study of the mechanisms of the aging process in the lung and its most commonly associated disorders: cancer, chronic obstructive pulmonary disease (COPD), and infectious diseases. The advantage of using naturally aged mice is that they present characteristics similar to those observed in human aging. The advantage of using IHC and QM methods lies in their simplicity, economic accessibility, and easy interpretation, in addition to the fact that they provide extremely important information. The study of the aging process in the lung and its associated diseases could allow the design of appropriate therapeutic strategies, which is extremely important considering that life expectancy and the number of elderly people continue to increase considerably worldwide.

20-Hydroxyecdysone Confers Antioxidant and Antineoplastic Properties in Human Non-Small Cell Lung Cancer Cells

20-Hydroxyecdysone (20E) is an arthropod hormone which is synthesized by some plants as part of their defense mechanism. In humans, 20E has no hormonal activity but possesses a number of beneficial pharmacological properties including anabolic, adaptogenic, hypoglycemic, and antioxidant properties, as well as cardio-, hepato-, and neuroprotective features. Recent studies have shown that 20E may also possess antineoplastic activity. In the present study, we reveal the anticancer properties of 20E in Non-Small Cell Lung Cancer (NSCLC) cell lines. 20E displayed significant antioxidant capacities and induced the expression of antioxidative stress response genes. The RNA-seq analysis of 20E-treated lung cancer cells revealed the attenuation of genes involved in different metabolic processes. Indeed, 20E suppressed several enzymes of glycolysis and one-carbon metabolism, as well as their key transcriptional regulators-c-Myc and ATF4, respectively. Accordingly, using the SeaHorse energy profiling approach, we observed the inhibition of glycolysis and respiration mediated by 20E treatment. Furthermore, 20E sensibilized lung cancer cells to metabolic inhibitors and markedly suppressed the expression of Cancer Stem Cells (CSCs) markers. Thus, in addition to the known beneficial pharmacological activities of 20E, our data uncovered novel antineoplastic properties of 20E in NSCLC cells.

The participation of tumor residing pericytes in oral squamous cell carcinoma

Pericytes are perivascular cells related to vessel structure and angiogenesis that can interact with neoplastic cells, interfering with cancer progression and outcomes. This study focused on the characterization of pericytes in oral squamous cell carcinoma (OSCC) using clinical samples and a transgenic mouse model of oral carcinogenesis. Nestin^-/NG2⁺ (type-1) and nestin⁺/NG2⁺ (type-2) pericytes were analyzed by direct fluorescence after induction of oral carcinogenesis (4-nitroquinoline-1-oxide). Gene expression of neuron glial antigen-2 (NG2), platelet-derived growth factor receptor beta (PDGFR-β), and cluster of differentiation 31 (CD31) was examined in human OSCC tissues. The protein expression of von Willebrand factor and NG2 was assessed in oral leukoplakia (i.e., oral potentially malignant disorders) and OSCC samples. Additionally, clinicopathological aspects and survival data were correlated and validated by bioinformatics using The Cancer Genome Atlas (TCGA). Induction of carcinogenesis in mice produced an increase in both NG2⁺ pericyte subsets. In human OSCC, advanced-stage tumors showed a significant reduction in CD31 mRNA and von Willebrand factor-positive vessels. Low PDGFR-β expression was related to a shorter disease-free survival time, while NG2 mRNA overexpression was associated with a reduction in overall survival, consistent with the TCGA data. Herein, oral carcinogenesis resulted in an increase in NG2⁺ pericytes, which negatively affected survival outcomes.

Expression of Markers Ki-67, Nestin, VEGF, CD34 and Apoptosis in Relatively Healthy Lung Tissue with Non-Changed and Metaplastic Bronchial Epithelium

BACKGROUND

Knowledge about the occurrence of processes such as proliferation, apoptosis and angiogenesis in healthy lung tissues with different bronchial epitheliums is limited, and further exploration can contribute to a better understanding of the physiological renewal of lung tissues. The processes mentioned above occur with the help of important tissue factors; therefore, the aim of the study was to determine the expression of markers Ki-67, nestin, CD34 and vascular endothelial growth factor (VEFG) and detect apoptotic cells in relatively healthy lung tissue.

METHODS

Samples of relatively healthy lung tissue were obtained from 19 patients and divided into groups of patients with non-changed and patients with metaplastic bronchial epithelium. Tissue samples were examined by hematoxylin and eosin staining. Ki-67, nestin, VEGF and CD34-positive cells were detected by the immunohistochemistry method. Terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) assay was carried out to detect apoptotic cells. The number of positive structures was counted semi-quantitatively by microscopy.

RESULTS

Ki-67-positive cells were detected in only one case. An occasional to moderate number of nestin-positive structures was found in various tissues of relatively healthy lungs with different bronchial epitheliums. No apoptotic cells were seen in non-changed bronchial epithelium, compared with few apoptotic cells in metaplastic bronchial epithelium. Metaplastic bronchial epithelium contained more VEGF-positive cells than non-changed bronchial epithelium. Samples with non-changed, and metaplastic bronchial epithelium both contained a similar number of CD34-positive structures.

CONCLUSIONS

Proliferative activity and programmed cell death are not prominent events in normal lung tissue. A moderate number of nestin-positive cells in the alveolar epithelium and cartilage of bronchi with pseudostratified ciliated epithelium suggests a significant role of neuronal origin cells in these structures, to be intensified in metaplastic bronchial epithelium. A practically non-changed number of CD34-positive cells excludes any difference in stimulation of endothelial origin cells between lungs with different types of epithelium, while an increase in VEGF in structures with metaplastic epithelium suggests the presence/influence of tissue ischemia impact on possible development/maintenance of metaplasia.

Nestin-GFP transgene labels immunoprivileged bone marrow mesenchymal stem cells in the model of ectopic foci formation

Immune privileges are demonstrated for different types of quiescent stem cells of adult mammalian organisms. Mesenchymal stem cells (MSCs) are believed to have immune privileges; however, an accurate experimental confirmation hasn’t been presented. Here, we provide direct experimental evidence that MSCs of C57Black/6J murine bone marrow (BM) are immune privileged in vivo and retain their functionality after prolonged exposure to the uncompromised immune system. The BM of Nes-Gfp transgenic mice was implanted as a tissue fragment under the kidney capsule in isogenic C57Black/6J immunocompetent recipients. Nestin-Gfp strain provides a fluorescent immunogenic marker for a small fraction of BM cells, including GFP+CD45– MSCs. Despite the exposure of xenogenically marked MSCs to the fully-functional immune system, primary ectopic foci of hematopoiesis formed. Six weeks after implantation, multicolor fluorescence cytometry revealed both GFP+CD45– and GFP+CD45+ cells within the foci. GFP+CD45– cells proportion was 2.0 × 10–5 ×÷9 and it didn’t differ significantly from syngenic Nes-GFP transplantation control. According to current knowledge, the immune system of the recipients should eliminate GFP+ cells, including GFP+ MSCs. These results show that MSCs evade immunity. Primary foci were retransplanted into secondary Nes-GFP recipients. The secondary foci formed, in which CD45–GFP+ cells proportion was 6.7 × 10–5 ×÷2.2, and it didn’t differ from intact Nes-GFP BM. The results demonstrate that MSCs preserve self-renewal and retain their functionality after prolonged immune exposure. The success of this study relied on the implantation of BM fragments without prior dissociation of cells and the fact that the vast majority of implanted cells were immunologically equivalent to the recipients.

Hypoxia-Induced Nestin Regulates Viability and Metabolism of Lung Cancer by Targeting Transcriptional Factor Nrf2, STAT3, and SOX2

Objective

To investigate hypoxia-induced Nestin regulates lung cancer viability and metabolism by targeting transcription factors Nrf2, STAT3, and SOX2.

Methods

Eighty-four cases of nonsmall cell lung cancer (nonsmall cell lung cancer, NSCLC), which had been treated from June 2020 to February 2021, were randomly selected from our clinicopathology database. Immunohistochemical staining of collected tissue cells was performed to assess the expression patterns of Nestin, STAT3, Nrf2, and SOX2. Data were quantified and statistically analyzed using one-way and two-way ANOVA tests with P < 0.05.

Results

Clinicopathological findings showed significant differences in lymph node metastasis, tissue differentiation, and histology on induction of Nestin expression; Nestin expression correlated with STAT3, Nrf2, and SOX2 expression.Nestin/STAT3/SOX2/Nrf2 are involved in angiogenesis and lung cancer development.

Conclusion

Hypoxia-induced Nestin promotes the progression of nonsmall lung cancer cells by targeting the downstream transcription factors STAT3, Nrf2, and SOX2.