PURPOSE: The long non-coding RNA H19, a conservatively imprinted gene, acts as a molecular sponge for the let-7 family, which has been identified as a set of tumor suppressors. However, the combined prognostic value of H19 and let-7a signature in breast cancer patients remains unclear. METHODS: In this research we assessed the prognostic value of the combined H19 and let-7a signature in breast cancer patients by retrospectively reviewing that data of 79 patients who underwent neoadjuvant chemotherapy; we also investigated the expression and function of H19 in breast cancer cell lines in vitro. Survival data were calculated using the Kaplan-Meier method and compared using the log-rank test. Univariate and multivariate survival analyses were conducted using the Cox proportional hazards regression method. As determined using X-tile, the optimal cutoff value for the risk score to assess progression-free survival (PFS) based on the combined signature was –0.1. RESULTS: Patients with an overall positive treatment response had higher let-7a and lower H19 levels. In addition, let-7a expression was negatively correlated with H19 expression. Patients with a risk score of >–0.1 had shorter overall survival and PFS. In vitro data showed that chemoresistant cell lines exhibit higher H19 and lower let-7a levels and knockdown H19 restores paclitaxel sensitivity. CONCLUSION: Our results suggest that the combined let-7a and H19 signature is a novel prognostic factor for breast cancer patients treated with neoadjuvant chemotherapy.
Breast Neoplasms* ; Breast* ; Cell Line ; Disease-Free Survival* ; Drug Therapy ; Humans ; In Vitro Techniques ; Methods ; Neoadjuvant Therapy ; Paclitaxel ; Porifera ; Prognosis ; Retrospective Studies ; RNA, Long Noncoding

Background:The musk glands of adult male Chinese forest musk deer(Moschus berezovskii Flerov,1929)(FMD),which are considered as special skin glands,secrete a mixture of sebum,lipids,and proteins into the musk pod.Together,these components form musk,which plays an important role in attracting females during the breeding season.However,the relationship between the musk glands and skin of Chinese FMD remains undiscovered.Here,the musk gland and skin of Chinese FMD were examined using histological analysis and RNA sequencing(RNA-seq),and the expression of key regulatory genes was evaluated to determine whether the musk gland is derived from the skin.Methods:A comparative analysis of musk gland anatomy between juvenile and adult Chinese FMD was conducted.Then,based on the anatomical structure of the musk gland,skin tissues from the abdomen and back as well as musk gland tissues were obtained from three juvenile FMD.These tissues were used for RNA-seq,hematoxylin-eosin(HE)staining,immunohistochemistry(IHC),western blot(WB),and quantitative real-time polymerase chain reaction(qRT-PCR)experiments.Results:Anatomical analysis showed that only adult male FMD had a complete glandular organ and musk pod,while juvenile FMD did not have any well-developed musk pods.Transcriptomic data revealed that 88.24%of genes were co-expressed in the skin and musk gland tissues.Kyoto Encyclopedia of Genes and Genomes(KEGG)signaling pathway analysis found that the genes co-expressed in the abdomen skin,back skin,and musk gland were enriched in biological development,endocrine system,lipid metabolism,and other pathways.Gene Ontology(GO)enrichment analysis indicated that the genes expressed in these tissues were enriched in biological processes such as multicellular development and cell division.Moreover,the Metascape predictive analysis tool demonstrated that genes expressed in musk glands were skin tissue-specific.qRT-PCR and WB revealed that sex-determining region Y-box protein 9(Sox9),Caveolin-1(Cav-1),and androgen receptor(AR)were expressed in all three tissues,although the expression levels differed among the tissues.According to the IHC results,Sox9 and AR were expressed in the nuclei of sebaceous gland,hair follicle,and musk gland cells,whereas Cav-1 was expressed in the cell membrane.Conclusions:The musk gland of Chinese FMD may be a derivative of skin tissue,and Sox9,Cav-1,and AR may play significant roles in musk gland development.