Advances in molecular mechanisms of interaction between Mycobacterium tuberculosis and lung cancer: a narrative review

Circular RNAs in tuberculosis and lung cancer

This review signifies the role of circular RNAs (circRNAs) in tuberculosis (TB) and lung cancer (LC), focusing on pathogenesis, diagnosis, and treatment. CircRNAs, a newly discovered type of non-coding RNA, have emerged as key regulators of gene expression and promising biomarkers in various bodily fluids due to their stability. The current review discusses circRNA biogenesis, highlighting their RNase-R resistance due to their loop forming structure, making them effective biomarkers. It details their roles in gene regulation, including splicing, transcription control, and miRNA interactions, and their impact on cellular processes and diseases. For LC, the review identifies circRNA dysregulation affecting cell growth, motility, and survival, and their potential as therapeutic targets and biomarkers. In TB, it addresses circRNAs' influence on host anti-TB immune responses, proposing their use as early diagnostic markers. The paper also explores the interplay between TB and LC, emphasizing circRNAs as dual biosignatures, and the necessity for differential diagnosis. It concludes that no single circRNA biomarker is universally applicable for both TB and LC. Ultimately, the review highlights the pivotal role of circRNAs in TB and LC, encouraging further research in biomarker identification and therapeutic development concomitant for both diseases.

From Case Reports to Molecular Insight: Examining the Outcomes and Underlying Mechanisms of Squamous Cell Carcinoma in Breast Implant Patients-A Systematic Review

There is extensive coverage in the existing literature on implant-associated lymphomas like anaplastic large-cell lymphoma, but breast implant-associated squamous cell carcinoma (BIA-SCC) has received limited scholarly attention since its first case in 1992. Thus, this study aims to conduct a qualitative synthesis focused on the underexplored association between breast implants and BIA-SCC. A systematic review was conducted utilizing the PubMed, Web of Science, and Cochrane databases to identify all currently reported cases of BIA-SCC. Additionally, a literature review was performed to identify potential biochemical mechanisms that could lead to BIA-SCC. Studies were vetted for quality using the NIH quality assessment tool. From an initial pool of 246 papers, 11 met the quality criteria for inclusion, examining a total of 14 patients aged between 40 and 81 years. BIA-SCC was found in a diverse range of implants, including those with smooth and textured surfaces, as well as those filled with saline and silicone. The condition notably manifested a proclivity for aggressive clinical progression, as evidenced by a mortality rate approximating 21.4% within a post-diagnostic interval of six months. Our literature review reveals that chronic inflammation, driven by various external factors such as pathogens and implants, can initiate carcinogenesis through epigenetic modifications and immune system alterations. This includes effects from exosomes and macrophage polarization, showcasing potential pathways for the pathogenesis of BIA-SCC. The study highlights the pressing need for further investigation into BIA-SCC, a subject hitherto inadequately addressed in the academic sphere. This necessitates the urgency for early screening and intervention to improve postoperative outcomes. While the review is confined by its reliance on case reports and series, it serves as a valuable reference for future research endeavors.

New progress of tuberculosis scar carcinoma

It has been demonstrated that scar tissue and fibrosis may increase the likelihood of developing malignancies. Specifically, scar tissue has been linked to the occurrence and progression of lung cancer (LC), though the precise mechanisms necessitate further research for explanation. Lung scarring can stem from various causes, with carcinogenesis on scarring lesions in pulmonary tuberculosis (PTB) being the most frequent (accounting for approximately 75% of cases). Notably, having previously cured, PTB is the second most common risk factor for LC after smoking, with approximately 3% of PTB patients experiencing LC as a secondary condition. This essay will delve into the mechanisms, treatment, and prognosis of tuberculosis scar carcinoma (TSC).

Screening of potential microbial markers for lung cancer using metagenomic sequencing

INTRODUCTION

Lung cancer is the most prevalent cancer with high mortality in China, and it is associated with the dysbiosis of the lung microbiome. This study attempted to screen for specific microorganisms as potential biomarkers for distinguishing benign lung disease from lung cancer.

METHODS

Bronchoalveolar lavage fluid (BALF) sample was selected in the study instead of saliva to avoid contamination with oral microorganisms, and microbial taxonomic and functional differences in BALF samples from patients with lung cancer and those with those from patients with benign lung diseases were performed based on metagenomic next-generation sequencing, for the first time, so that microorganisms other than bacteria could be included.

RESULTS

The results showed that the intrasample diversity of malignant samples was different from benign samples, and the microbial differences among malignant samples were smaller, with lower microbial diversity, significantly changed microbial abundance and metabolic functions. Metabolic function analysis revealed amino acid-related metabolism was more prevalent in benign samples, whereas carbohydrate-related metabolism was more prevalent in malignant samples. By LEfSe, Metastat and Random Forest analysis, we identified a series of important differential microorganisms. Importantly, the model combining five key genera plus one tumor marker (neuron-specific enolase) as indicators presented the optimal disease typing performance.

CONCLUSION

Thus results suggest the value of these differential microorganisms enriched in tumors in mechanism research and may be potential new targets for lung cancer therapy. More importantly, the biomarkers identified in this study can be conducive to improve the clinical diagnosis of lung cancer and have good application prospects.

Global morbidity and mortality of central nervous system tuberculosis: a systematic review and meta-analysis

Background

Tuberculosis (TB) is the second most common cause of death due to a single infectious agent worldwide after COVID-19. Up to 15% of the cases are extrapulmonary, and if it is located in the central nervous system (CNS-TB), it presents high morbidity and mortality. Still, the global epidemiology of CNS-TB remains unknown.

Aim

To estimate the global prevalence and incidence of CNS-TB based on the available literature.

Methods

We systematically searched in MEDLINE, Cochrane Central, Scopus, and LILACS databases (April 2020) and included observational studies evaluating the epidemiology of CNS-TB. Two independent researchers selected and assessed the quality of the studies and extracted relevant data. We performed random-effects model meta-analysis of proportions to estimate the pooled prevalence. The protocol of this study was registered in PROSPERO (CRD 42018103946).

Results

We included 53 studies from 28 countries, representing 12,621 patients with CNS-TB. The prevalence of CNS-TB was 2 per 100,000 inhabitants. According to the clinical setting, the prevalence of CNS-TB represented the 13.91% of all cases of meningitis and 4.55% of all cases of TB. The mortality was calculated by tuberculous meningitis due to the lack of data of other presentation, and it rose up to 42.12% in hospitalized patients. The burden of countries’ TB, Human Development Index (HDI), and the prevalence of HIV were the most important prevalence moderators, especially in patients with TB. No data on incidence were found.

Conclusion

The prevalence and mortality of CNS-TB remain high, and TB meningitis is the most frequent presentation. The highest prevalence was reported in developing countries, and its main moderators were the countries’ HDI and HIV infection. Our study was limited by high heterogeneity, risk of bias, and potential data under registration from developing countries. The integration of CNS-TB early detection and management into national TB programs and population-based studies from developing countries are needed for better global estimation and response.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-022-11052-8.

Alterations of lung microbiota in patients with non-small cell lung cancer

The role of lung microbiota in non-small cell lung cancer remains unclear. We investigated the characteristics and functional roles of lung microbiota in non-small cell lung cancer. Bronchoalveolar lavage fluid samples were obtained from patients with non-small cell lung cancer (n = 46) and with benign lung disease (n = 29). The differences in composition and gene expression in the microbiota between the samples were analyzed using 16s rRNA sequencing. The oncogenic genus (Veillonella) was then evaluated in the progression of lung cancer in C57 BL/6 mice. Compared to benign lung disease, the lung microbiota in non-small cell lung cancer was significantly altered, both in terms of α- and β-diversity. In terms of bacterial composition, the non-small cell lung cancer group was enriched with two Phyla (Firmicutes, Bacteroidetes) and three genera (Streptococcus, Prevotella, Veillonella). Prevotella and Veillonella were most strongly associated with non-small cell lung cancer, and Veillonella significantly promoted the progression of lung cancer in vivo. Moreover, metabolic prediction revealed that ribosomes, biosynthesis of secondary metabolites, and pyrimidine metabolism were among the enriched pathways that may be involved in the progression of non-small cell lung cancer. Overall, results suggest that the progression of non-small cell lung cancer is followed by significant changes in the composition and function of the lung microbiota. These differing genera may be potential diagnostic markers and therapeutic targets.