Exploring the role of antibiotics and steroids in managing respiratory diseases.

Respiratory diseases (RDs), such as chronic obstructive pulmonary disease, cystic fibrosis, asthma, and pneumonia, are associated with significant morbidity and mortality. Treatment usually consists of antibiotics and steroids. Relevant published literature reviews, studies, and clinical trials were accessed from institutional and electronic databases. The keywords used were respiratory diseases, steroids, antibiotics, and combination of steroids and antibiotics. Selected articles and literature were carefully reviewed. Antibiotics are often prescribed as the standard therapy to manage RDs. Types of causative respiratory pathogens, spectrum of antibiotics activity, route of administration, and course of therapy determine the type of antibiotics that are prescribed. Despite being associated with good clinical outcome, treatment failure and recurrence rate are still high. In addition, antibiotic resistance has been widely reported due to bacterial mutations in response to the use of antibiotics, which render them ineffective. Nevertheless, there has been a growing demand for corticosteroids (CS) and antibiotics to treat a wide variety of diseases, including various airway diseases, due to their immunosuppressive and anti-inflammatory properties. The use of CS is well established and there are different formulations based on the diseases, such as topical administration, tablets, intravenous injections, and inhaled preparations. Both antibiotics and CS possess similar properties in terms of their anti-inflammatory effects, especially regulating cytokine release. Thus, the current review examines and discusses the different applications of antibiotics, CS, and their combination in managing various RDs. Drawbacks of these interventions are also discussed.

Abrus agglutinin stimulates BMP-2-dependent differentiation through autophagic degradation of ß-catenin in colon cancer stem cells.

Eradicating cancer stem cells (CSCs) in colorectal cancer (CRC) through differentiation therapy is a promising approach for cancer treatment. Our retrospective tumor-specimen analysis elucidated alteration in the expression of bone morphogenetic protein 2 (BMP-2) and ß-catenin during the colon cancer progression, indicating that their possible intervention through "forced differentiation" in colon cancer remission. We reveal that Abrus agglutinin (AGG) induces the colon CSCs differentiation, and enhances sensitivity to the anticancer therapeutics. The low dose AGG (max. dose = 100 ng/mL) decreased the expression of stemness-associated molecules such as CD44 and ß-catenin in the HT-29 cell derived colonospheres. Further, AGG augmented colonosphere differentiation, as demonstrated by the enhanced CK20/CK7 expression ratio and induced alkaline phosphatase activity. Interestingly, the AGG-induced expression of BMP-2 and the AGG-induced differentiation were demonstrated to be critically dependent on BMP-2 in the colonospheres. Similarly, autophagy-induction by AGG was associated with colonosphere differentiation and the gene silencing of BMP-2 led to the reduced accumulation of LC3-II, suggesting that AGG-induced autophagy is dependent on BMP-2. Furthermore, hVps34 binds strongly to BMP-2, indicating a possible association of BMP-2 with the process of autophagy. Moreover, the reduction in the self-renewal capacity of the colonospheres was associated with AGG-augmented autophagic degradation of ß-catenin through an interaction with the autophagy adaptor protein p62. In the subcutaneous HT-29 xenograft model, AGG profoundly inhibited the growth of tumors through an increase in BMP-2 expression and LC3-II puncta, and a decrease in ß-catenin expression, confirming the antitumor potential of AGG through induction of differentiation in colorectal cancer.