Therapeutic Strategies to Prevent the Recurrence of Nasal Polyps after Surgical Treatment: An Update and In Vitro Study on Growth Inhibition of Fibroblasts

Circulating Exosomal microRNA Profiles Associated with Risk of Postoperative Recurrence in Chronic Rhinosinusitis with Nasal Polyps

Background

Exosomes carry various types of transcripts and serve as promising biomarkers for inflammatory diseases. However, the role of serum exosomal microRNAs (miRNAs) in chronic rhinosinusitis with nasal polyps (CRSwNP) is poorly clarified.

Methods

A prospective exploratory cohort of 10 CRSwNP patients was conducted, and the serum exosome samples were subjected to miRNA sequencing. Two independent prospective cohorts, consisting of 40 and 54 patients respectively, were recruited from different medical centers for validation. These cohorts were monitored for over two years, with postoperative recurrence serving as the primary outcome measure. The top 3 differentially exosomal miRNAs were validated in the serum samples, and their predictive values for recurrence were assessed.

Results

Eight CRSwNP patients completed the follow-up, comprising 4 non-recurrent cases and 4 recurrent cases. Distinctive profiles of serum exosomal miRNAs were identified between the two groups. In the first validation cohort, reverse transcription-polymerase chain reaction results indicated elevated serum exosomal miR-3174 and miR-6750-5p expressions, along with reduced miR-192-3p levels in the recurrence group compared to the non-recurrence group. Receiver operating characteristic (ROC) curves and Kaplan-Meier survival analysis demonstrated significant correlations between expressions of exosomal miR-3174 and miR-192-3p and the risk of postoperative recurrence. These findings were further validated in the second cohort, confirming the elevation of both miRNAs in the recurrence group and their associations with recurrence risk. Additionally, serum exosomal miR-3174 levels increased in recurrent cases compared to their baseline levels.

Conclusion

Circulating exosomal microRNA signatures may influence the risk of postoperative recurrence in CRSwNP patients. Serum exosomal elevated exosomal miR-3174 and decreased miR-192-3p were correlated with CRSwNP recurrence risk.

The Inhibition Effect and Mechanism of Staurosporine Isolated from Streptomyces sp. SNC087 Strain on Nasal Polyp

This study aims to explore the potential inhibition effects of staurosporine isolated from a Streptomyces sp. SNC087 strain obtained from seawater on nasal polyps. Staurosporine possesses antimicrobial and antihypertensive activities. This research focuses on investigating the effects of staurosporine on suppressing the growth and development of nasal polyps and elucidating the underlying mechanisms involved. The experimental design includes in vitro and ex vivo evaluations to assess the inhibition activity and therapeutic potential of staurosporine against nasal polyps. Nasal polyp-derived fibroblasts (NPDFs) were stimulated with TGF-β1 in the presence of staurosporine. The levels of α-smooth muscle actin (α-SMA), collagen type-I (Col-1), fibronectin, and phosphorylated (p)-Smad 2 were investigated using Western blotting. VEGF expression levels were analyzed in nasal polyp organ cultures treated with staurosporine. TGF-β1 stimulated the production of Col-1, fibronectin, and α-SMA and was attenuated by staurosporine pretreatment. Furthermore, these inhibitory effects were mediated by modulation of the signaling pathway of Smad 2 in TGF-β1-induced NPDFs. Staurosporine also inhibits the production of VEGF in ex vivo NP tissues. The findings from this study will contribute to a better understanding of staurosporine's role in nasal polyp management and provide insights into its mechanisms of action.

Biologics for Chronic Rhinosinusitis-A Modern Option for Therapy

Chronic rhinosinusitis (CRS) is an important ENT pathology which affects about 5-12% of the general population. The treatment of CRS can be pharmacological (nasal sprays, douches, systemic antibiotics and steroids), surgical (endoscopic sinus surgery) or immunological according to established algorithms. CRS was divided for many years into CRS with nasal polyps (CRSwNP) and CRS without nasal polyps (CRSsNP). New ways of classifying CRS by endotypes (presence of neutrophilia, eosinophilia, fibrosis, glandular hypertrophy and epithelial dysmorphisms) appeared after the most recent understandings of the pathophysiology of the disease. Other classifications divide CRS into primary and secondary forms, localized/diffuse types and anatomical presentation. A new type of treatment has been administered in the last years, biologics. For the moment, biologics are indicated just in the cases of the patients who have undergone ESS or have contraindications for surgery and have bilateral polyps and meet a minimum of three of the following criteria: the necessity for systemic therapies with oral or parenteral corticosteroids or contraindications to systemic steroids, significant loss of smell or impaired QoL score, comorbid asthma and type 2 inflammation. This article aims to present the most relevant studies which used the three types of biologics (anti-IgE, anti-IL5 and anti-IL4/IL3) and wishes to increase the awareness of this new type of treatment that can be used in some CRS cases.