Regulation of gene expression by tobacco product preparations in cultured human dermal fibroblasts

The role of cancer stromal fibroblasts in mediating the effects of tobacco-induced cancer cell growth

Tobacco products cause a variety of cancers, nicotine and carcinogens are two major factors to link the tobacco products and various cancers. The mechanism of tobacco inducing carcinogenesis and promoting cancer progression have been studied for a long time. However, mainstream studies just focus on the mutagenic characteristics of tobacco product and its properties to induce carcinogenesis of epithelial cells. In the past decades, people began to aware of the significant role of tumor stroma in cancer development and progression. Fibroblasts, which is associated with various cancer in all stage of disease progression, are the dominant cell type in the tumor microenvironment. While only a few studies explore the crosstalk between tobacco-induced fibroblasts and surrounding epithelial cells. Our purpose is to systematically review the effects of tobacco products on fibroblasts and further discuss how these effects affect the development of cancer cells.

Research on the correlation between activating transcription factor 3 expression in the human coronary artery and atherosclerotic plaque stability

Background

Activating transcription factor 3 (ATF3) is an early response gene that is activated in response to atherosclerotic stimulation and may be an important factor in inhibiting the progression of atherosclerosis. In this study, we directly measured the expression of ATF3 and inflammatory factors in human coronary atherosclerotic plaques to examine the relationship between ATF3 expression, inflammation and structural stability in human coronary atherosclerotic plaques.

Methods

A total of 68 coronary artery specimens were collected from the autopsy group, including 36 cases of sudden death from coronary heart disease (SCD group) and 32 cases of acute death caused by mechanical injury with coronary atherosclerosis (CHD group). Twenty-two patients who had no coronary heart disease were collected as the control group (Con group). The histological structure of the coronary artery was observed under a light microscope after routine HE staining, and the intimal and lesion thicknesses, thickness of the fibrous cap, thickness of necrosis core, degree of lumen stenosis were assessed by image analysis software. Western blotting and immunohistochemistry were used to measure the expression and distribution of ATF3, inflammatory factors (CD45, IL-1β, TNF-α) and matrix metalloproteinase-9 (MMP-9) and vascular cell adhesion molecule 1 (VCAM1) in the coronary artery. The Pearson correlation coefficient was used to analyse the correlation between ATF3 protein expression and inflammatory factors and between ATF3 protein expression and structure-related indexes in the lesion group.

Results

Compared with those in the control group, the intima and necrotic core in the coronary artery were thickened, the fibrous cap became thin and the degree of vascular stenosis was increased in the lesion group, while the intima and necrotic core became thicker and the fibrous cap became thinner in the SCD group than in the CHD group (P < 0.05). There was no or low expression of ATF3, inflammatory factors, VCAM1 and MMP-9 in the control group, and the expression of inflammatory factors, VCAM1 and MMP-9 in the SCD group was higher than that in CHD group, while the expression of ATF3 in the SCD group was significantly lower than that in CHD group (P < 0.05). In the lesion group, the expression of ATF3 was negatively correlated with intimal and necrotic focus thickness, positively correlated with fibrous cap thickness (P < 0.01), and negatively correlated with inflammatory factors, VCAM1 and MMP-9 (P < 0.01).

Conclusions

The expression of ATF3 may be related to the progression and stability of atherosclerotic plaques, and may affect the structural stability of atherosclerotic plaques by regulating the inflammatory response, thus participating in the regulation of atherosclerotic progression.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02161-9.

Combustible Cigarette and Smokeless Tobacco Product Preparations Differentially Regulate Intracellular Calcium Mobilization in HL60 Cells

Changes in the level of intracellular calcium ([Ca²⁺]_i) are central to leukocyte signaling and immune response. Although evidence suggests that cigarette smoking affects inflammatory response via an increase in intracellular calcium, it remains unclear if the use of smokeless tobacco (e.g., moist snuff) elicits a similar response. In this study, we evaluated the effects of tobacco product preparations (TPPs), including total particulate matter (TPM) from 3R4F reference cigarettes, smokeless tobacco extract (STE) from 2S3 reference moist snuff, and nicotine alone on Ca²⁺ mobilization in HL60 cells. Treatment with TPM, but not STE or nicotine alone, significantly increased [Ca²⁺]_i in a concentration-dependent manner in HL60 cells. Moreover, TPM-induced [Ca²⁺]_i increase was not related to extracellular Ca²⁺ and did not require the activation of the IP3 pathway nor involved the transient receptor potential (TRP) channels. Our findings indicate that, in cells having either intact or depleted endoplasmic reticulum (ER) Ca²⁺ stores, TPM-mediated [Ca²⁺]_i increase involves cytosolic Ca²⁺ pools other than thapsigargin-sensitive ER Ca²⁺ stores. These results, for the first time, demonstrate that TPM triggers [Ca²⁺]_i increases, while significantly higher nicotine equivalent doses of STE or nicotine alone, did not affect [Ca²⁺]_i under the experimental conditions. In summary, our study suggests that in contrast with STE or nicotine preparations, TPM activates Ca²⁺ signaling pathways in HL60 cells. The differential effect of combustible and non-combustible TPPs on Ca²⁺ mobilization could be a useful in vitro endpoint for tobacco product evaluation.

Human Dermal Fibroblast: A Promising Cellular Model to Study Biological Mechanisms of Major Depression and Antidepressant Drug Response

BACKGROUND

Human dermal fibroblasts (HDF) can be used as a cellular model relatively easily and without genetic engineering. Therefore, HDF represent an interesting tool to study several human diseases including psychiatric disorders. Despite major depressive disorder (MDD) being the second cause of disability in the world, the efficacy of antidepressant drug (AD) treatment is not sufficient and the underlying mechanisms of MDD and the mechanisms of action of AD are poorly understood.

OBJECTIVE

The aim of this review is to highlight the potential of HDF in the study of cellular mechanisms involved in MDD pathophysiology and in the action of AD response.

METHODS

The first part is a systematic review following PRISMA guidelines on the use of HDF in MDD research. The second part reports the mechanisms and molecules both present in HDF and relevant regarding MDD pathophysiology and AD mechanisms of action.

RESULTS

HDFs from MDD patients have been investigated in a relatively small number of works and most of them focused on the adrenergic pathway and metabolism-related gene expression as compared to HDF from healthy controls. The second part listed an important number of papers demonstrating the presence of many molecular processes in HDF, involved in MDD and AD mechanisms of action.

CONCLUSION

The imbalance in the number of papers between the two parts highlights the great and still underused potential of HDF, which stands out as a very promising tool in our understanding of MDD and AD mechanisms of action.

Chronic Exposure to Chewing Tobacco Induces Metabolic Reprogramming and Cancer Stem Cell-Like Properties in Esophageal Epithelial Cells

Tobacco in its smoke and smokeless form are major risk factors for esophageal squamous cell carcinoma (ESCC). However, molecular alterations associated with smokeless tobacco exposure are poorly understood. In the Indian subcontinent, tobacco is predominantly consumed in chewing form. An understanding of molecular alterations associated with chewing tobacco exposure is vital for identifying molecular markers and potential targets. We developed an in vitro cellular model by exposing non-transformed esophageal epithelial cells to chewing tobacco over an eight-month period. Chronic exposure to chewing tobacco led to increase in cell proliferation, invasive ability and anchorage independent growth, indicating cell transformation. Molecular alterations associated with chewing tobacco exposure were characterized by carrying out exome sequencing and quantitative proteomic profiling of parental cells and chewing tobacco exposed cells. Quantitative proteomic analysis revealed increased expression of cancer stem cell markers in tobacco treated cells. In addition, tobacco exposed cells showed the Oxidative Phosphorylation (OXPHOS) phenotype with decreased expression of enzymes associated with glycolytic pathway and increased expression of a large number of mitochondrial proteins involved in electron transport chain as well as enzymes of the tricarboxylic acid (TCA) cycle. Electron micrographs revealed increase in number and size of mitochondria. Based on these observations, we propose that chronic exposure of esophageal epithelial cells to tobacco leads to cancer stem cell-like phenotype. These cells show the characteristic OXPHOS phenotype, which can be potentially targeted as a therapeutic strategy.

Differential Expression of c-fos Proto-Oncogene in Normal Oral Mucosa versus Squamous Cell Carcinoma

Background: The c-Fos nuclear protein dimerizes with Jun family proteins to form the transcription factor AP-1 complex which participates in signal transduction and regulation of normal cellular processes. In tumorigenesis, c-Fos promotes invasive growth through down-regulation of tumor suppressor genes but its role in oral carcinogenesis is not clear. Objectives: This study concerned c-fos gene expression in normal and malignant tissues of the oral cavity, with attention to associations between expression status and clinico-pathological profiles of OSCC patients. Method: A total of 65 histopathologically confirmed OSCC tissue samples were included in case group along with an equal number of age and sex-matched normal tissue samples of oral cavity for the control group. c-Fos protein and m-RNA expressions were analyzed using immunohistochemistry and qRT-PCR, respectively. Results: A significant low expression of c-Fos protein was observed in OSCC cases than normal control subjects (p= <0.001). The mean percent positivity of c-Fos protein in cases vs. controls was 24.91± 2.7 vs. 49.68± 2.2 (p= <0.001). Most OSCC tissue samples showed weak or moderate c-Fos expression whereas 53.8% of normal tissue sections presented with strong immunostaining. Moreover, the relative m-RNA expression for the c-fos gene was significantly decreased in case group (0.93± 0.48) as compared to the control group (1.22± 0.87). Majority of c-Fos positive cases were diagnosed with well developed tumor. The mean percent positivity of c-Fos protein was significantly lower in higher grade tumor as compared with normal oral mucosa (p= < 0.001). Conclusion: The present study suggested that the c-fos gene is downregulated in oral carcinomas. The disparity of c-Fos protein levels in different pathological grades of tumor and normal oral tissue samples may indicate that loss of c-Fos expression is related with the progression of OSCC.