Cryptococcosis with pulmonary cavitation in an immunocompetent child: a case report and literature review.

BACKGROUND: Pulmonary cryptococcosis (PC) rarely occurs in immunocompetent children. CASE PRESENTATION: A 13-year-old boy was admitted to the First Affiliated Hospital of Ningbo University in February 2023 with complaints of cough and chest pain. Physical examination showed slightly moist rales in the right lung. Chest computed tomography (CT) suggested a lung lesion and cavitation. Blood routine test, lymphocyte subsets, immunoglobulin, and complement tests indicated that the immune system was normal. However, the serum cryptococcal antigen test was positive. Next-generation sequencing revealed Cryptococcus infection. The child was diagnosed with PC and was discharged after treating with fluconazole 400 mg. Four months later, chest CT showed that the lung lesion diminished, and reexamination of serum cryptococcal antigen test turned positive. CONCLUSION: PC should be considered in an immunocompetent child with pulmonary cavities with nonspecific symptoms.

Tumor-suppressing effects of miR-381-3p in pediatric acute myeloid leukemia via ROCK1 downregulation.

MicroRNA (miR)-381-3p is the newly discovered tumor-associated miRNA, which is frequently associated with diverse human malignancies; but, it is still unknown about its effect on acute myeloid leukemia (AML) in children. This work focused on exploring miR-381-3p's effect on childhood AML and identifying the possible mechanisms facilitating new treatment development. Using qRT-PCR analysis, miR-381-3p expression remarkably reduced in pediatric AML patients and AML cell lines (HL-60 and U937). Following transfection of miR-381-3p mimic or inhibitor into HL-60 and U937 cells, we conducted MTT assay to evaluate cell proliferation, flow cytometry (FCM) to measured cell apoptosis and cell cycle, whereas Transwell assays to detect cell invasion and migration. Our results demonstrated that miR-381-3p overexpression remarkably repressed cell growth, invasion and migration; additionally, miR-381-3p overexpression resulted in arrest of cell cycle and enhanced cell apoptosis. In contrast, miR-381-3p knockdown led to an opposite effect. Moreover, we predicted miR-381's target gene and validated it by luciferase reporter assay and TargetScan, separately. We identified miR-381-3p's binding site in ROCK1 3'-UTR. As revealed by Western-blot (WB) assay, miR-381-3p overexpression notably suppressed ROCK1 level. Moreover, restoring ROCK1 expression abolished miR-381-3p's inhibition on cell proliferation, invasion and migration. Data in this work indicated the role of miR-381-3p as the tumor suppressor within pediatric AML by targeting ROCK1. Therefore, miR-381-3p might serve as a potential therapeutic target for the treatment of pediatric AML.