Objective:To investigate the expression of indoleamine 2,3-dioxygenase 1(IDO1)in different types of breast cancer tissues and its relationship with patient prognosis and immune cell infiltration.Methods:RNA sequencing data of breast cancer and corresponding clinical information from the TCGA database were collected.The differential expression of IDO1 mRNA in various breast cancer tissues(different subtypes,stages,menopause statuses,and age groups)and adjacent normal tissues were analyzed.Breast cancer patients with significant differences in IDO1 mRNA expression were divided into high and low expression groups,and their disease-specific survival(DSS)was compared between the two groups.The relationship between IDO1 mRNA expression and immune cell infiltration in cancer tissues with significant DSS differences was analyzed.Immunohistochemistry was used to detect IDO1 protein expression in ER-negative,PR-negative,HER2-positive,and stage Ⅱ breast cancer tissues,to verify the data from the database.Results:IDO1 mRNA was highly expressed in breast cancer tissues but varied across different breast cancer types.IDO1 mRNA was highly expressed in breast cancer tissues of patients with ER-negative,PR-negative,HER2-positive,HER2-negative subtypes,stage Ⅱ,T2 stage,N0 stage,M0 stage,premenopausal,postmenopausal,and age≤60 years(P<0.05 or P<0.01,or P<0.001).In the ER-negative,PR-negative,HER2-positive,and stage Ⅱ subgroups,breast cancer tissues patients with high IDO1 mRNA expression had significantly higher DSS than those with low expression(P<0.05 or P<0.01).In ER-negative,PR-negative,HER2-positive,and stageⅡ breast cancer tissues,IDO1 mRNA expression was associated with immune cell infiltration,including activated dendritic cells(aDCs),Th1 cells,T cells,CD56dim NK cells,CTLs,and Treg cells(all P<0.001).IDO1 protein was highly expressed in ER-negative,PR-negative,HER2-positive,and stage Ⅱ breast cancer tissues(all P<0.001),consistent with the data from the database.Conclusion:IDO1 expression varies across different types of breast cancer tissues.The expression of IDO1 is associated with the prognosis and immune cell infiltration in ER-negative,PR-negative,HER2-positive,and at stage Ⅱ breast cancer patients.

ObjectiveTo investigate the effect of phytoestrogen biochanin A （BCA） on liver fibrosis induced by CCl₄ in female mice with bilateral oophorectomy （ovariectomized） and its mechanism. MethodsA total of 50 ovariectomized Kunming mice were selected and given intraperitoneal injection of CCl₄ to establish a model of liver fibrosis， and then according to body weight， they were randomly divided into model group， positive control group， and low-， middle-， and high-dose BCA groups， with 10 mice in each group. In addition， 10 female mice in the same litter were given resection of a small amount of adipose tissue near both ovaries to establish the sham-operation group. The mice in the positive control group were given estradiol 2 mg/kg by gavage， and those in the low-， middle-， and high-dose BCA groups were given BCA by gavage at a dose of 25， 50， and 100 mg/kg， respectively， once a day for 7 consecutive weeks； the mice in the sham-operation group and the model group were given an equal volume of 0.5% sodium carboxymethyl cellulose solution by gavage. The mice were anesthetized and sacrificed after administration to collect samples. Liver index and uterus index were measured； HE staining and Masson staining were used to observe liver histopathological changes； the biochemical analysis was used to measure the activity of aspartate aminotransferase （AST） and alanine aminotransferase （ALT）； ELISA was used to measure the levels of interleukin-6 （IL-6） and tumor necrosis factor-α （TNF-α） in liver tissue， and Western blot was used to measure the relative protein expression levels of collagen Ⅰ， transforming growth factor-beta 1 （TGF-β₁）， alpha-smooth muscle actin （α-SMA）， estrogen receptor beta （ERβ）， and p-NF-κBp65/NF-κBp65 in liver tissue. The t-test was used for comparison of continuous data between two groups； a one-way analysis of various was used for comparison between multiple groups， and the least significant difference t-test was used for further comparison between two groups. The Kruskal-Wallis H test was used for comparison of non-normally distributed continuous data between multiple groups and further comparison between two groups. ResultsCompared with the sham-operated group， the model group had a significant increase in liver index and a significant reduction in uterus index， as well as significant increases in the activities of serum AST and ALT， the levels of IL-6 and TNF-α in liver tissue， and the protein expression levels of collagen Ⅰ， TGF-β₁， α-SMA， and p-NF-κBp65/NF-κBp65 in liver tissue （all P<0.05）， with no significant change in the expression of ERβ in liver tissue （P>0.05）， and the model group showed significant fibrosis lesions in the liver， such as hepatocyte edema， steatosis， and necrosis with inflammatory cell infiltration and hyperplasia， deposition， and staggered distribution of collagen fibers. Compared with the model group， the low-， middle-， and high-dose BCA groups had significant reductions in liver index， the activities of serum AST and ALT， the levels of IL-6 and TNF-α， and the protein expression levels of collagen Ⅰ， TGF-β₁， α-SMA， and p-NF-κBp65/NF-κBp65 in liver tissue （all P<0.05）， with no significant change in uterine index （P>0.05）， as well as a significant increase in the protein expression level of ERβ in liver tissue （P<0.05） and varying degrees of improvement in liver fibrosis lesions. ConclusionBCA can effectively improve CCL₄-induced liver fibrosis in ovariectomized female mice， possibly by upregulating ERβ to inhibit the NF-κB signaling pathway and then alleviating inflammatory response.