Cigarette smoke extract modulates E-Cadherin, Claudin-1 and miR-21 and promotes cancer invasiveness in human colorectal adenocarcinoma cells

Effect of age, COPD severity, and cigarette smoke exposure on bronchial epithelial barrier function

We investigated the effect of age, cigarette smoke, and chronic obstructive pulmonary disease (COPD) severity on epithelial barrier function. Primary bronchial epithelial cells (PBECs) were obtained from bronchial brushings in eight younger and eight older never-smokers; seven older ex-smokers without COPD, eight patients with COPD Global Initiative for Chronic Obstructive Lung Disease (GOLD) I-III and six patients with COPD GOLD IV, and cultured in the absence/presence of cigarette smoke extract (CSE). Epithelial barrier function was assessed by electric resistance sensing and expression of junctional and antioxidant genes/proteins quantified by qPCR/immunodetection. Epithelial barrier function was comparable between PBECs from younger and older never-smokers. PBECs from ex-smokers had significantly lower barrier function compared with never-smokers, with a further decrease in COPD GOLD IV. CSE decreased epithelial barrier function from which PBECs from never-smokers, but not ex-smokers with and without COPD, recovered. Restoration of barrier function was accompanied by increased expression of barrier and antioxidant genes. At baseline, PBECs from ex-smokers with and without COPD had higher expression of junctional and antioxidant genes compared with never-smokers. However, exposure to CSE increased antioxidant (SOD1-3, CAT) gene expression only in PBECs from never-smokers and ex-smokers without COPD. In conclusion, our data indicate that cigarette smoking and COPD severity are associated with reduced epithelial barrier function, which is potentially driven by an imbalance in the antioxidant response.NEW & NOTEWORTHY Cigarette smoking and chronic obstructive pulmonary disease (COPD) severity are associated with reduced epithelial barrier function that is potentially driven by an imbalance in the antioxidant response.

Identification of a Novel miR-195-5p/PNN Axis in Colorectal Cancer

Pinin (PNN) is a desmosome-associated protein that reinforces the organization of keratin intermediate filaments and stabilizes the anchoring of the cytoskeleton network to the lateral surface of the plasma membrane. The aberrant expression of PNN affects the strength of cell adhesion as well as modifies the intracellular signal transduction pathways leading to the onset of CRC. In our previous studies, we characterized the role of miR-195-5p in the regulation of desmosome junctions and in CRC progression. Here, with the aim of investigating additional mechanisms related to the desmosome complex, we identified PNN as a miR-195-5p putative target. Using a public data repository, we found that PNN was a negative prognostic factor and was overexpressed in colon cancer tissues from stage 1 of the disease. Then, we assessed PNN expression in CRC tissue specimens, confirming the overexpression of PNN in tumor sections. The increase in intracellular levels of miR-195-5p revealed a significant decrease in PNN at the mRNA and protein levels. As a consequence of PNN regulation by miR-195-5p, the expression of KRT8 and KRT19, closely connected to PNN, was affected. Finally, we investigated the in vivo effect of miR-195-5p on PNN expression in the colon of AOM/DSS-treated mice. In conclusion, we have revealed a new mechanism driven by miR-195-5p in the regulation of desmosome components, suggesting a potential pharmacological target for CRC therapy.

Smoking as a risk factor for colorectal neoplasms in young individuals? A systematic meta-analysis

BACKGROUND AND AIMS

Early-onset colorectal neoplasms (EoCRN) include both benign and malign colorectal tumors, which occur before the age of 50. The incidence of EoCRN is rising worldwide. Tobacco smoking has previously been proven to be related to the development of various tumor types. However, its relationship with EoCRN is not clearly defined. Hence, we carried out a systematic review and a meta-analysis to evaluate the relationship between smoking status and the risk of EoCRN.

METHODS

A systematic search of PubMed, EMBASE, and Web of Science up to September 7, 2022, was performed for studies that evaluated the association of smoking status with EoCRN. The quality of the case-control study was evaluated with the Newcastle‒Ottawa Scale. The quality of the cross-sectional studies was evaluated with the American Health Care Research and Quality checklist. Fixed-effects models were used to pool odds ratios (ORs) to evaluate the relationship between the risk of developing EoCRN and smoking status. The meta-analyses were performed with Review Manager version 5.4, and funnel plots and publication bias tests were produced by STATA software.

RESULTS

A total of six studies were included in this meta-analysis. After pooling the results of these six studies, we found that current smokers carry a relatively high risk of developing EoCRN (OR, 1.33; 95% confidence interval [CI], 1.17-1.52) compared to never-smokers. Ex-smokers were not at a significantly increased risk for developing EoCRN (OR, 1.00; 95% CI, 0.86-1.18).

DISCUSSION

Smoking behavior is significantly associated with an increased risk for developing EoCRN and might be one of the reasons for the increasing incidence. Ex-smokers who quit are not at significant risk of developing EoCRN.

Pre-clinical and clinical importance of miR-21 in human cancers: Tumorigenesis, therapy response, delivery approaches and targeting agents

The field of non-coding RNA (ncRNA) has made significant progress in understanding the pathogenesis of diseases and has broadened our knowledge towards their targeting, especially in cancer therapy. ncRNAs are a large family of RNAs with microRNAs (miRNAs) being one kind of endogenous RNA which lack encoded proteins. By now, miRNAs have been well-coined in pathogenesis and development of cancer. The current review focuses on the role of miR-21 in cancers and its association with tumor progression. miR-21 has both oncogenic and onco-suppressor functions and most of the experiments are in agreement with the tumor-promoting function of this miRNA. miR-21 primarily decreases PTEN expression to induce PI3K/Akt signaling in cancer progression. Overexpression of miR-21 inhibits apoptosis and is vital for inducing pro-survival autophagy. miR-21 is vital for metabolic reprogramming and can induce glycolysis to enhance tumor progression. miR-21 stimulates EMT mechanisms and increases expression of MMP-2 and MMP-9 thereby elevating tumor metastasis. miR-21 is a target of anti-cancer agents such as curcumin and curcumol and its down-regulation impairs tumor progression. Upregulation of miR-21 results in cancer resistance to chemotherapy and radiotherapy. Increasing evidence has revealed the role of miR-21 as a biomarker as it is present in both the serum and exosomes making them beneficial biomarkers for non-invasive diagnosis of cancer.

The Prognostic Impact of Quitting Smoking at or around Diagnosis on the Survival of Patients with Gastrointestinal Cancers: A Systematic Literature Review

Simple Summary

Smokers are at high risk of cancer of the gastrointestinal system, and many patients with newly diagnosed cancer of the oesophagus, stomach, colon-rectum, and liver are active smokers at diagnosis. In this review, we focused on whether stopping smoking shortly before diagnosis or afterwards (e.g., during treatment) may improve the chance of survival for these patients. We reviewed the scientific literature up to April 2022 and found only seven articles focusing on this topic. While very limited in number, these studies provided suggestive evidence in favour of a beneficial effect of smoking cessation for these patients. Smokers with newly diagnosed cancer of the gastrointestinal system should be encouraged to stop smoking and provided all the necessary support to achieve this goal.

Abstract

Cigarette smoking is a strong risk factor for the occurrence of gastrointestinal cancers, and a substantial proportion of newly diagnosed patients is made up of active smokers, yet the impact of smoking cessation at or around diagnosis on the clinical course of these cancers (whose prognosis is often unfavourable) has never been summarized to date. We reviewed studies published until 30 April 2022 that investigated whether smoking cessation at or around diagnosis favourably affects the clinical course of gastrointestinal cancers patients. Six studies were included for colorectal cancer patients, which provided limited yet suggestive evidence that quitters may have longer disease-specific survival compared to continued smokers. Only one study each focused on patients with gastric or HBV-positive liver cancer (both reporting a survival advantage for quitters vs. continued smokers), while we found no eligible studies for patients with cancer at other sites within the digestive system. More research is urgently needed to expand the evidence on the topic, given the potentially major clinical implications for these patients. Moreover, health professionals should provide the necessary smoking cessation support to any smoker who is undergoing diagnostic work-up or treatment for gastrointestinal cancer.

Nicotine-induced miR-21-3p promotes chemoresistance in lung cancer by negatively regulating FOXO3a

Lung cancer is the leading cause of cancer-related mortality worldwide and cigarette smoking is reported to contribute to the lung cancer-related mortality. The present study aimed to investigate the molecular mechanism underlying nicotine-induced chemoresistance in lung cancer. The expression of microRNA (miR)-21-3p and its predicted target FOXO3a in lung cancer cells was detected via reverse transcription-quantitative PCR, in the presence or absence of nicotine. The regulatory effect of miR-21-3p and FOXO3a on lung cancer cell proliferation and apoptosis induced by docetaxel or cisplatin treatment was evaluated by performing Cell Counting Kit-8 and Annexin V/PI staining assays, respectively. The interaction between miR-21-3p and FOXO3a was analyzed by performing luciferase reporter assays and western blotting. FOXO3a overexpression rescue experiments were conducted in vitro and in vivo using a xenograft mouse model to assess the function of miR-21-3p/FOXO3a in lung cancer. Nicotine induced miR-21-3p expression in lung cancer cells in a dose-dependent manner. miR-21-3p downregulated FOXO3a expression by directly binding to the 3′-untranslated region of FOXO3a. Moreover, miR-21-3p knockdown sensitized lung cancer cells to docetaxel or cisplatin treatment. Mechanistically, FOXO3a was predicted as a direct target of miR-21-3p. FOXO3a overexpression promoted the chemosensitivity of lung cancer cells to docetaxel or cisplatin treatment. Furthermore, FOXO3a overexpression antagonized the regulatory function of miR-21-3p on docetaxel- or cisplatin-treated lung cancer cells. In the docetaxel- or cisplatin-treated lung cancer xenograft mouse model, miR-21-3p promoted chemoresistance via negatively regulating FOXO3a. Therefore, the present study demonstrated that nicotine-induced miR-21-3p promoted chemoresistance to docetaxel or cisplatin treatment via negatively regulating FOXO3a, which may serve as a novel therapeutic strategy for the treatment of patients with chemoresistant lung cancer.

miR-144 inhibits the IGF1R-ERK1/2 signaling pathway via NUDCD1 to suppress the proliferation and metastasis of colorectal cancer cells: a study based on bioinformatics and in vitro and in vivo verification

PURPOSE

Colorectal cancer (CRC) is a severe health condition characterized by high mortalities. NudC domain containing 1 (NUDCD1) is abnormally upregulated in multiple tumors and is recognized as a cancer antigen. In CRC, NUDCD1 upregulation accelerates tumor progression by activating the IGF1R-ERK1/2 signaling pathway. Its specific regulatory mechanisms, however, remain unclear.

METHODS

In the present study, we predicted the regulators of NUDCD1 and analyzed the expression profile of NUDCD1 in CRC tissues using the gene chip dataset. We also determined the regulation between miR-144, NUDCD1 and IGF1R-ERK1/2 signaling in vitro and in vivo. Then, the expression of miR-144 in CRC tissues was detected and its cell functions were verified in vitro.

RESULTS

As predicted by bioinformatics, we found that NUDCD1 is a predicted target of miR-144 and confirmed that miR-144 directly binds to NUDCD1. In vitro and in vivo, miR-144 was determined to specifically regulate NUDCD1 expression and as such, can reduce the activity of the IGF1R-ERK1/2 signaling pathway. Moreover, miR-144 was significantly downregulated in CRC tissues; its levels were significantly negatively correlated with CRC primary range and lymph node metastasis. Cell function studies verified that miR-144 acts as a tumor suppressor, because it significantly inhibits the proliferation, metastasis, and invasion of CRC cells as well as inducing cell cycle arrest and apoptosis.

CONCLUSIONS

Our study demonstrates that miR-144 regulates IGF1R-ERK1/2 signaling via NUDCD1 to inhibit CRC cell proliferation and metastasis. The miR-144/NUDCD1/IGF1R-ERK1/2 signaling axis may be crucial in the progression of CRC.

Comparative Investigation of Cellular Effects of Polyethylene Glycol (PEG) Derivatives

Nowadays, polyethylene glycols referred to as PEGs are widely used in cosmetics, consumer care products, and the pharmaceutical industry. Their advantageous properties such as chemical stability, low immunogenicity, and high tolerability explain why PEGs are applied in many fields of pharmaceutical formulations including parenteral, topical, ophthalmic, oral, and rectal preparations and also in modern drug delivery systems. Given their extensive use, they are considered a well-known group of chemicals. However, the number of large-scale comparative studies involving multiple PEGs of wide molecular weight range is low, as in most cases biological effects are estimated upon molecular weight. The aim of this publication was to study the action of PEGs on Caco-2 cells and G. mellonella larvae and to calculate the correlation of these effects with molecular weight and osmolality. Eleven PEGs of different molecular weight were used in our experiments: PEG 200, PEG 300, PEG 400, PEG 600, PEG 1000, PEG 1500, PEG 4000, PEG 8000, PEG 10,000, 12,000, and PEG 20,000. The investigated cellular effects included cytotoxicity (MTT and Neutral Red assays, flow cytometry with propidium iodide and annexin V) and autophagy. The osmolality of different molecular weight PEGs with various concentrations was measured by a vapor pressure osmometer OSMOMAT 070 and G. mellonella larvae were injected with the solutions of PEGs. Sorbitol was used as controls of the same osmolality. Statistical correlation was calculated to describe the average molecular weight dependence of the different measured effects. Osmolality, the cytotoxicity assays, flow cytometry data, and larvae mortality had significant correlation with the structure of the PEGs, while autophagosome formation and the proportion of early apoptotic cells showed no statistical correlation. Overall, it must be noted that PEGs must be tested individually for biological effects as not all effects can be estimated by the average molecular weight.

Active Enhancer Assessment by H3K27ac ChIP-seq Reveals Claudin-1 as a Biomarker for Radiation Resistance in Colorectal Cancer

Background

Colorectal cancer (CRC) represents the third most common malignant tumor in the worldwide. Radiotherapy is the common therapeutic treatment for CRC, but radiation resistance is often encountered. ChIP-seq of Histone H3K27 acetylation (H3K27ac) has revealed enhancers that play an important role in CRC. This study examined the relationship between an active CRC enhancer and claudin-1 (CLDN1), and its effect on CRC radiation resistance.

Methods

The target CRC genes of active enhancers were obtained from public H3K27ac ChIP-seq, and the genes highly expressed in radio-resistant CRC were screened and intersected with enhancer-driven genes. The clinical roles of CLDN1 in radiation resistance were examined using the t-test, standard mean deviation (SMD), summary receiver operating characteristic curve and Kaplan-Meier curves. The co-expressed genes of CLDN1 were calculated using Pearson Correlation analysis, and Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes and Gene Set Variation Analysis (GSVA) analyses were used to examine the molecular mechanisms of CLDN1.

Results

Total 13 703 CRC genes were regulated by enhancers using 58 H3K27ac ChIP-seq. Claudin-1 (CLDN1) was enhancer-driven and notably up-regulated in CRC tissues compared to non-CRC controls, with a SMD of 3.45 (95 CI % = .56-4.35). CLDN1 expression was increased in radiation-resistant CRC with a SMD of .42 (95% CI = .16-.68) and an area under the curve of .74 (95% CI = .70-.77). The cell cycle and immune macrophage levels were the most significant pathways associated with CLDN1.

Conclusion

CLDN1 as an enhancer-regulated gene that can boost radiation resistance in patients with CRC.

Smoking is a risk factor for postoperative ileus after radical resection in male patients

Most smokers are males, and smoking has been indicated as a risk factor for many cancers as well as postoperative complications after cancer surgery. However, little is known about whether smoking is a risk factor for postoperative ileus (POI) after radical rectal cancer resection in males. The aim of this study was to assess whether smoking is a risk factor for POI after radical resection in male rectal cancer patients.Data of 1486 patients who underwent radical resection for rectal cancer were extracted from the clinical medical system in our hospital and were statistically analyzed. POI was defined as nausea, vomiting or pain, failure to have bowel function for more than 4 days postoperatively, and absence of a mechanical bowel obstruction.The rate of POI was 12.79%. Univariate analysis showed that patients in the POI group were more likely to have a history of smoking and drinking and receive intraperitoneal chemotherapy and had a larger intraperitoneal chemotherapy dosage. In the multivariable analysis, smoking remained significantly associated with a higher incidence of POI (OR 2.238, 95% CI [1.545-3.240], P = .000). The results also showed that patients who received postoperative patient-controlled intravenous analgesia had a lower incidence of POI.Male patients with a history of smoking who undergo elective radical resection for rectal cancer have an increased risk for POI complications.

Regulation of microRNA-21 expression by natural products in cancer

Natural products have been of much interest in research studies owing to their wide pharmacological applications, chemical diversity, low side effects, and multitarget activities. Examples of these compounds include matrine, sulforaphane, silibinin, curcumin, berberin, resveratrol, and quercetin. Some of the present anticancer drugs, such as taxol, vincristine, vinblastine, and doxorubicin are also derived from natural products. The anti-carcinogenic effects of these products are partly mediated through modulation of microRNA-21 (miR-21) expression. To date, numerous downstream targets of miR-21 have been recognized, which include phosphatase and tensin homolog (PTEN), ras homolog gene family member B (RHOB), phosphoinositide 3-kinase/protein kinase B (PI3K/Akt), programmed cell death 4 (PDCD4), signal transducer and activator of transcription (STAT)-3, and nuclear factor kappa B (NF-κB) pathways. These signaling pathways, their regulation by oncomiR-21 in cancer, and the modulating impact of natural products are the main focus of this review.

Tumor Suppressor miR-584-5p Inhibits Migration and Invasion in Smoking Related Non-Small Cell Lung Cancer Cells by Targeting YKT6

Simple Summary

Cigarette smoke is a major carcinogen that causes lung cancer and induces DNA methylation. DNA methylation regulates the expression of microRNA (miRNAs), which are important regulators of cancer biology. However, the association between smoking and miRNAs has not been fully elucidated in smoking-related lung carcinogenesis. In this study, we found that miR-584-5p expression was downregulated with cancer progression using a lung carcinogenesis model cell line. Moreover, we demonstrated that miR-584-5p is downregulated by the methylation of its promoter region and that it suppresses migration and invasion by targeting YKT6 in smoking-related non-small cell lung cancer (NSCLC) cells. Our results provide a better understanding of the underlying changes in miRNA expression in smoking-related lung carcinogenesis and suggest that miR-584-5p is a potential molecular biomarker for smoking-related NSCLC.

Abstract

Cigarette smoke (CS) affects the expression of microRNAs (miRNAs), which are important regulators of gene expression by inducing DNA methylation. However, the effects of smoking on miRNA expression have not been fully elucidated in smoking-related lung carcinogenesis. Therefore, in this study, to investigate the change of miRNA expression pattern and to identify tumor suppressor miRNAs by smoking in lung carcinogenesis, we used lung carcinogenesis model cell lines that, derived from a murine xenograft model with human bronchial epithelial cells (BEAS-2B), exposed CS or not. The microarray analysis revealed that miR-584-5p expression was downregulated with cancer progression in lung carcinogenesis model cell lines. We confirmed by pyrosequencing that the methylation level of the miR-584-5p promoter increased with cancer progression. In vitro and in vivo experiments showed that miR-584-5p suppressed migration and invasion in non-small cell lung cancer (NSCLC) cells by targeting YKT6. Furthermore, we showed that high level of YKT6 was associated with a poor survival rate in NSCLC patients with a history of smoking. These results suggest that miR-584-5p acts as a tumor suppressor and is a potential molecular biomarker for smoking-related NSCLC.

MicroRNAs as Potential Regulators of Immune Response Networks in Asthma and Chronic Obstructive Pulmonary Disease

Chronic respiratory diseases (CRDs) are an important factor of morbidity and mortality, accounting for approximately 6% of total deaths worldwide. The main CRDs are asthma and chronic obstructive pulmonary disease (COPD). These complex diseases have different triggers including allergens, pollutants, tobacco smoke, and other risk factors. It is important to highlight that although CRDs are incurable, various forms of treatment improve shortness of breath and quality of life. The search for tools that can ensure accurate diagnosis and treatment is crucial. MicroRNAs (miRNAs) are small non-coding RNAs and have been described as promising diagnostic and therapeutic biomarkers for CRDs. They are implicated in multiple processes of asthma and COPD, regulating pathways associated with inflammation, thereby showing that miRNAs are critical regulators of the immune response. Indeed, miRNAs have been found to be deregulated in several biofluids (sputum, bronchoalveolar lavage, and serum) and in both structural lung and immune cells of patients in comparison to healthy subjects, showing their potential role as biomarkers. Also, miRNAs play a part in the development or termination of histopathological changes and comorbidities, revealing the complexity of miRNA regulation and opening up new treatment possibilities. Finally, miRNAs have been proposed as prognostic tools in response to both conventional and biologic treatments for asthma or COPD, and miRNA-based treatment has emerged as a potential approach for clinical intervention in these respiratory diseases; however, this field is still in development. The present review applies a systems biology approach to the understanding of miRNA regulatory networks in asthma and COPD, summarizing their roles in pathophysiology, diagnosis, and treatment.

Tea polyphenols and their chemopreventive and therapeutic effects on colorectal cancer

Colorectal cancer (CRC), a multifactorial disease, is usually induced and developed through complex mechanisms, including impact of diet and lifestyle, genomic abnormalities, change of signaling pathways, inflammatory response, oxidation stress, dysbiosis, and so on. As natural polyphenolic phytochemicals that exist primarily in tea, tea polyphenols (TPs) have been shown to have many clinical applications, especially as anticancer agents. Most animal studies and epidemiological studies have demonstrated that TPs can prevent and treat CRC. TPs can inhibit the growth and metastasis of CRC by exerting the anti-inflammatory, anti-oxidative or pro-oxidative, and pro-apoptotic effects, which are achieved by modulations at multiple levels. Many experiments have demonstrated that TPs can modulate several signaling pathways in cancer cells, including the mitogen-activated protein kinase pathway, phosphatidylinositol-3 kinase/Akt pathway, Wnt/β-catenin pathway, and 67 kDa laminin receptor pathway, to inhibit proliferation and promote cell apoptosis. In addition, novel studies have also suggested that TPs can prevent the growth and metastasis of CRC by modulating the composition of gut microbiota to improve immune system and decrease inflammatory responses. Molecular pathological epidemiology, a novel multidisciplinary investigation, has made great progress on CRC, and the further molecular pathological epidemiology research should be developed in the field of TPs and CRC. This review summarizes the existing in vitro and in vivo animal and human studies and potential mechanisms to examine the effects of tea polyphenols on CRC.

MicroRNA‑21 contributes to renal cell carcinoma cell invasiveness and angiogenesis via the PDCD4/c‑Jun (AP‑1) signalling pathway

Accumulating evidence has demonstrated that microRNAs are associated with malignant biological behaviour, including tumorigenesis, cancer progression and metastasis via the regulation of target gene expression. Our previous study demonstrated that programmed cell death protein 4 (PDCD4), which is a tumour suppressor gene, is a target of microRNA‑21 (miR‑21), which affects the proliferation and transformation capabilities of renal cell carcinoma (RCC) cells. However, the role of miR‑21 in the molecular mechanism underlying the migration, invasion and angiogenesis of RCC remains poorly understood. The effects of miR‑21 on the invasion, migration and angiogenesis of RCC cells was determined through meta‑analysis and regulation of miR‑21 expression in vitro. After searching several databases, 6 articles including a total of 473 patients met the eligibility criteria for this analysis. The combined results of the meta‑analysis revealed that increased miR‑21 expression was significantly associated with adverse prognosis in patients with RCC, with a pooled hazard ratio estimate of 1.740. In in vitro experiments, we demonstrated that a miR‑21 inhibitor decreased the number of migrating and invading A498 and 786‑O RCC cells, along with a decrease in PDCD4, c‑Jun, matrix metalloproteinase (MMP)2 and MMP9 expression. Additionally, inhibition of miR‑21 was revealed to reduce tube formation and tube junctions in the endothelial cell line HMEC‑1 by affecting the expression of angiotensin‑1 and vascular endothelial growth factor A, whereas PDCD4 small interfering RNA exerted opposite effects on the same cells. Overall, these findings, along with evidence‑based molecular biology, demonstrated that miR‑21 expression promoted the migration, invasion and angiogenic abilities of RCC cells by directly targeting the PDCD4/c‑Jun signalling pathway. The results may help elucidate the molecular mechanism underlying the development and progression of RCC and provide a promising target for microRNA‑based therapy.