Genomic Insights into Idiopathic Granulomatous Mastitis through Whole-Exome Sequencing: A Case Report of Eight Patients.

Idiopathic granulomatous mastitis (IGM) is a rare condition characterised by chronic inflammation and granuloma formation in the breast. The aetiology of IGM is unclear. By focusing on the protein-coding regions of the genome, where most disease-related mutations often occur, whole-exome sequencing (WES) is a powerful approach for investigating rare and complex conditions, like IGM. We report WES results on paired blood and tissue samples from eight IGM patients. Samples were processed using standard genomic protocols. Somatic variants were called with two analytical pipelines: nf-core/sarek with Strelka2 and GATK4 with Mutect2. Our WES study of eight patients did not find evidence supporting a clear genetic component. The discrepancies between variant calling algorithms, along with the considerable genetic heterogeneity observed amongst the eight IGM cases, indicate that common genetic drivers are not readily identifiable. With only three genes, CHIT1, CEP170, and CTR9, recurrently altering in multiple cases, the genetic basis of IGM remains uncertain. The absence of validation for somatic variants by Sanger sequencing raises further questions about the role of genetic mutations in the disease. Other potential contributors to the disease should be explored.

Evaluation of significantly changed chemokine factors of idiopathic granulomatous mastitis in non-puerperal patients.

Idiopathic granulomatous mastitis (IGM), a recurrent inflammation disease of the non-lactating breast, has had an increasing clinical morbidity rate in recent years, and its complicated symptoms and unclear etiology make it challenging to treat. This rare benign inflammatory breast disease, centered on the lobules, represents the most challenging type of non-puerperal mastitis (NPM), also known as non-lactating mastitis. In this study, patients diagnosed with IGM (M, n = 23) were recruited as cases, and patients with benign control breast disease (C, n = 17) were enrolled as controls. Cytokine microarray detection measured and analyzed the differentially expressed cytokine factors between IGM and control patients. Then, we verified the mRNA and protein expression levels of the significantly changed cytokine factors using Q-RT-PCR, ELISA, western blot, and IHC experiments. The cytokine factor expression levels significantly changed compared to the control group. We observed a significant increase between IGM and control patients in cytokine factors expression, such as interleukin-1ß (IL-1ß), monokine induced by gamma interferon (MIG), macrophage inflammatory protein (MIP)-1α, MIP-1ß, tumor necrosis factor receptor 2 (TNF RII). Then, we verified the expression of these top five dysregulated factors in both mRNA and protein levels. Our results demonstrated the cytokine map in IGM and indicated that several cytokines, especially chemokines, were associated with and significantly dysregulated in IGM tissues compared to the control group. The chemokine factors involved might be essential in developing and treating IGM. These findings would be helpful for a better understanding of IGM and offer valuable insights for devising novel diagnostic and therapeutic strategies.

Circulating miR-155, let-7c, miR-21, and PTEN levels in differential diagnosis and prognosis of idiopathic granulomatous mastitis and breast cancer.

This study investigates whether the circulating miR-155, let-7c, miR-21, and PTEN levels to be used in the differential diagnosis of patients with idiopathic granulomatous mastitis (IGM) and breast cancer (BC). Forty-five patients with BC, 50 patients with IGM, and 48 healthy volunteers were included in the study. Serum miR-21 expression was significantly higher in BC (fold change = 2.42) and IGM group (fold change = 1.33) compared to control (p < .001). Serum miR-155 and let-7c expression levels were significantly lower in both groups compared to the control group (p < .001). miR-21 expression in BC was significantly higher than IGM (fold change = 1.976; p < .001). PTEN levels in BC were significantly higher than IGM (p < .001) and significantly lower than the control group (p < .001); the IGM group was significantly lower than the control group (p < .001). In addition to radiological data, serum miR-21 and PTEN levels may be noninvasive biomarkers that can help differentiate IGM from BC. The results of the study will lead to future studies in the differential diagnosis of IGM and BC.

Broadleaf Mahonia attenuates granulomatous lobular mastitis­associated inflammation by inhibiting CCL­5 expression in macrophages.

Granulomatous lobular mastitis (GLM) is a type of chronic mammary inflammation with unclear etiology. Currently systematic corticosteroids and methitrexate are considered as the main drugs for GLM treatment, but a high toxicity and risk of recurrence greatly limit their application. It is therefore an urgent requirement that safe and efficient natural drugs are found to improve the GLM prognosis. Broadleaf Mahonia (BM) is a traditional Chinese herb that is believed to have anti­inflammatory properties according to ancient records of traditional Chinese medicine. The present study investigated this belief and demonstrated that BM significantly inhibited the expression of interleukin­1ß (IL­1ß), IL­6, cyclooxygenase­2 and inducible nitric oxide synthase in RAW264.7 cells, but had little influence on the cell viability, cell cycle and apoptosis. Meanwhile, the lipopolysaccharide­induced elevation of reactive oxygen species and nitric oxide was also blocked following BM treatment, accompanied with decreased activity of nuclear factor­κB and MAPK signaling. A cytokine array further validated that BM exhibited significant inhibitory effects on several chemoattractants, including chemokine (C­C motif) ligand (CCL)­2, CCL­3, CCL­5 and secreted tumor necrosis factor receptor 1, among which CCL­5 exhibited the highest inhibition ratio in cell and clinical GLM specimens. Collectively, the results show that BM is a novel effective anti­inflammatory herb in vitro and ex vivo, and that CCL­5 may be closely associated with GLM pathogenesis.