Prognostic impact of malignant diseases in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis and intestinal disorders: An observational study

BACKGROUND AND AIM

Idiopathic pulmonary fibrosis (IPF) is a chronic respiratory disease characterized by a progressive decline in lung function and a specific histopathologic pattern defined as usual interstitial pneumonia. Early diagnosis and new therapeutic protocols have contributed to a reduction in disease progression. Thus, some patients may develop extrapulmonary diseases including malignancies and chronic pathologies. The aim of this study was to investigate the frequency of intestinal disorders such as polyps, colorectal carcinoma (CRC), and chronic inflammatory bowel disease (IBD) in patients with IPF.

METHODS

From the database of 189 patients with IPF (148 males, 78.3 %; 41 females, 21.7 %) residing in the district of Modena, we identified 44 patients (36 males, 81.8 %; 8 females, 18.2 %) with a histologically confirmed intestinal disease.

RESULTS

Intestinal polyps were detected in 41 cases (93.2 %), of which 4 were associated with CRC and 1 with IBD; 1 patient had only CRC (2.3 %), and 2 patients had only IBD (4.5 %). Both males and females developed bowel disease, but males seemed to have a higher number of polyps and high-grade adenomas with a predisposition to malignant transformation.

CONCLUSIONS

As patients with IPF may present with intestinal diseases that can evolve into malignancies in some cases, they should undergo appropriate follow-up and targeted colorectal screening. Thus, colorectal pathologies should not take a back seat. These preliminary results encourage further research to select suitable patients for specific diagnostic and therapeutic procedures in order to prolong survival and improve the quality of life.

The CHST11 gene is linked to lung cancer and pulmonary fibrosis

BACKGROUND

The abnormal modification of chondroitin sulfate is one of the leading causes of disease, including cancer progression. During chondroitin sulfate biosynthesis, the CHST11 enzyme plays a vital role in its modification, but its role in cancer is not fully understood. Therefore, understanding the relationship between CHST11 and pulmonary-related diseases through clinically relevant information may be useful for diagnosis or treatment.

METHODS

A variety of pulmonary fibrosis clinical gene expression omnibus (GEO) datasets were used to assess the association between CHST11-related manifestations and fibrosis. Multiple lung cancer-related databases, including The Cancer Genome Atlas, GEO datasets, UCSC Xena, GEPIA2, Cbioportal and ingenuity pathway analysis were used to evaluate the clinical correlation between CHST11 and lung cancer and potential molecular mechanisms. For drug repurposing prediction, the molecules that correlated with CHST11 were subjected to the LINCS L1000 algorithm. A variety of in vitro assays were performed to evaluate the in-silico models, including RNA and protein expression, proliferation, migration and invasion.

RESULTS

Clinical analyses indicate that the levels of CHST11 are significantly elevated in cases of pulmonary-related diseases, including fibrosis and lung cancer. According to multiple lung cancer cohorts, CHST11 is the only member of the carbohydrate sulfotransferase family associated with overall survival for lung adenocarcinomas, and it is highly related to smoking-induced lung cancer patients. Based on the results of in vitro experiments, CHST11 expression contributes to tumor malignancy and promotes multiple fibrotic activators. Correlation-based ingenuity pathway analysis indicated that CHST11-related molecules contributed to pulmonary fibrosis or lung adenocarcinomas via similar upstream stimulators. Based on known molecular regulatory relationships, CHST11 has been associated with the regulation of TGF-β and INFγ as important molecules contributing to fibrosis and cancer progression. Interestingly, WordCloud analysis revealed that CHST11-related molecules are involved in regulation primarily by integrin signaling, and these relationships were consistently reflected in the analysis of cell lines and the clinical correlation. A CHST11 signature-based drug repurposing analysis demonstrated that the CHST11/integrin axis could be targeted by AG-1478 (Tyrphostin AG 1478), brefeldin A, geldanamycin and importazole.

CONCLUSIONS

This study provides the first demonstration that CHST11 may be used as a biomarker for pulmonary fibrosis or lung cancer, and the levels of CHST11 were increased by TGF-β and INFγ. The molecular simulation analyses demonstrate that the CHST11/integrin axis is a potential therapeutic target for treating lung cancer.

Identification and Validation of Aging-Related Genes in Idiopathic Pulmonary Fibrosis

Aging plays a significant role in the occurrence and development of idiopathic pulmonary fibrosis (IPF). In this study, we aimed to identify and verify potential aging-associated genes involved in IPF using bioinformatic analysis. The mRNA expression profile dataset GSE150910 available in the Gene Expression Omnibus (GEO) database and R software were used to identify the differentially expressed aging-related genes involved in IPF. Hub gene expression was validated by other GEO datasets. Gene ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were performed on differentially expressed aging-related genes. Subsequently, aging-related genes were further screened using three techniques (least absolute shrinkage and selection operator (LASSO) regression, support vector machine, and random forest), and the receiver operating characteristic curves were plotted based on screening results. Finally, real-time quantitative polymerase chain reaction (qRT-PCR) was performed to verify the RNA expression of the six differentially expressed aging-related genes using the blood samples of patients with IPF and healthy individuals. Sixteen differentially expressed aging-related genes were detected, of which the expression of 12 were upregulated and four were downregulated. GO and KEGG enrichment analyses indicated the presence of several enriched terms related to senescence and apoptotic mitochondrial changes. Further screening by LASSO regression, support vector machine, and random forest identified six genes (IGF1, RET, IGFBP2, CDKN2A, JUN, and TFAP2A) that could serve as potential diagnostic biomarkers for IPF. Furthermore, qRT-PCR analysis indicated that among the above-mentioned six aging-related genes, only the expression levels of IGF1, RET, and IGFBP2 in patients with IPF and healthy individuals were consistent with the results of bioinformatic analysis. In conclusion, bioinformatics analysis identified 16 potential aging-related genes associated with IPF, and clinical sample validation suggested that among these, IGF1, RET, and IGFBP2 might play a role in the incidence and prognosis of IPF. Our findings may help understand the pathogenesis of IPF.

Bioinformatics Analysis Identifies Potential Ferroptosis Key Genes in the Pathogenesis of Pulmonary Fibrosis

Objective: Ferroptosis has an important role in developing pulmonary fibrosis. The present project aimed to identify and validate the potential ferroptosis-related genes in pulmonary fibrosis by bioinformatics analyses and experiments.

Methods: First, the pulmonary fibrosis tissue sequencing data were obtained from Gene Expression Omnibus (GEO) and FerrDb databases. Bioinformatics methods were used to analyze the differentially expressed genes (DEGs) between the normal control group and the pulmonary fibrosis group and extract ferroptosis-related DEGs. Hub genes were screened by enrichment analysis, protein-protein interaction (PPI) analysis, and random forest algorithm. Finally, mouse pulmonary fibrosis model was made for performing an exercise intervention and the hub genes’ expression was verified through qRT-PCR.

Results: 13 up-regulated genes and 7 down-regulated genes were identified as ferroptosis-related DEGs by comparing 103 lung tissues with idiopathic pulmonary fibrosis (IPF) and 103 normal lung tissues. PPI results indicated the interactions among these ferroptosis-related genes. Kyoto Encyclopedia of Genes and Genomes (KEGG) Pathway enrichment and Genome-Ontology (GO) enrichment analyses showed that these ferroptosis-related genes involved in the organic anion transport, response to hypoxia, response to decrease oxygen level, HIF-1 signaling pathway, renal cell carcinoma, and arachidonic acid metabolism signaling pathway. The confirmed genes using PPI analysis and random forest algorithm included CAV1, NOS2, GDF15, HNF4A, and CDKN2A. qRT-PCR of the fibrotic lung tissues from the mouse model showed that the mRNA levels of NOS2 and GDF15 were up-regulated, while CAV1 and CDKN2A were down-regulated. Also, treadmill training led to an increased expression of CAV1 and CDKN2A and a decrease in the expression of NOS2 and GDF15.

Conclusion: Using bioinformatics analysis, 20 potential genes were identified to be associated with ferroptosis in pulmonary fibrosis. CAV1, NOS2, GDF15, and CDKN2A were demonstrated to be influencing the development of pulmonary fibrosis by regulating ferroptosis. These findings suggested that, as an aerobic exercise treatment, treadmill training reduced ferroptosis in the pulmonary fibrosis tissues, and thus, reduces inflammation in the lungs. Aerobic exercise training initiate concomitantly with induction of pulmonary fibrosis reduces ferroptosis in lung. These results may develop our knowledge about pulmonary fibrosis and may contribute to its treatment.

The Value of 18F-FDG PET/CT in Evaluating Disease Severity and Prognosis in Idiopathic Pulmonary Fibrosis Patients

BACKGROUND

Several parameters are useful for assessing disease severity in idiopathic pulmonary fibrosis (IPF); however, the role of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) is not well-defined. We aimed to evaluate the value of ¹⁸F-FDG PET/CT for assessing disease severity and prognosis in IPF patients.

METHODS

Clinical data of 89 IPF patients (mean age: 68.1 years, male: 94%) who underwent ¹⁸F-FDG PET/CT for evaluation of lung nodules or cancer staging were retrospectively reviewed. Mean and maximal standardized uptake values (SUV_mean, SUV_max, respectively) were measured in the fibrotic area. Adjusted SUV, including SUV ratio (SUVR, defined as SUV_max-to-liver SUV_mean ratio), tissue fraction-corrected SUV_mean (SUV_meanTF), and SUVR (SUVR_TF), and tissue-to-blood ratio (SUV_max/SUV_mean venous; TBR_blood) were obtained. Death was defined as the primary outcome, and associations between other clinical parameters (lung function, exercise capacity, C-reactive protein [CRP] level) were also investigated.

RESULTS

All SUV parameters were inversely correlated with the forced vital capacity, diffusing capacity for carbon monoxide, and positively correlated with CRP level and the gender-age-physiology index. The SUV_mean, SUV_max, and SUV_meanTF were associated with changes in lung function at six months. The SUVR (hazard ratio [HR], 1.738; 95% confidence interval [CI], 1.011-2.991), SUVR_TF (HR, 1.441; 95% CI, 1.000-2.098), and TBR_blood (HR, 1.377; 95% CI, 1.038-1.827) were significant predictors for mortality in patients with IPF in the univariate analysis, but not in the multivariate analysis.

CONCLUSION

¹⁸F-FDG PET/CT may provide additional information on the disease severity and prognosis in IPF patients, and the SUVR may be superior to other SUV parameters.