Ovarian cancer: a molecularly insidious disease / 癌症

In this issue of the Chinese Journal of Cancer, European, American, and Chinese experts review the current management and future perspectives of epithelial ovarian cancer (EOC), the leading cause of gynecological cancer deaths. Although major advances have been made in understanding the cellular and molecular biology of this highly heterogeneous malignancy, the survival rate of women with EOC has changed little since the introduction of platinum-based treatment as a front-line therapy. The papers describe the progress in deciphering the molecular complexity of this disease and the newly available molecular-driven therapies, which have been applied by shifting trial designs toward restricting eligibility to specific subgroups of patients rather than testing agents in unselected populations. These new trial designs provide potential opportunities for improved efficacy in targeted populations. Given the molecular complexity of this disease, patient survival may be increased by searching for new molecular prognostic/predictive signatures as well as by translating the recent insight of microRNA involvement in EOC progression into new, targeted therapies. Particular attention has been given to the issue of fertility sparing for women affected by curable diseases.

Key nodes of a microRNA network associated with the integrated mesenchymal subtype of high-grade serous ovarian cancer / 癌症

Metastasis is the main cause of cancer mortality. One of the initiating events of cancer metastasis of epithelial tumors is epithelial-to-mesenchymal transition (EMT), during which cells dedifferentiate from a relatively rigid cell structure/morphology to a flexible and changeable structure/morphology often associated with mesenchymal cells. The presence of EMT in human epithelial tumors is reflected by the increased expression of genes and levels of proteins that are preferentially present in mesenchymal cells. The combined presence of these genes forms the basis of mesenchymal gene signatures, which are the foundation for classifying a mesenchymal subtype of tumors. Indeed, tumor classification schemes that use clustering analysis of large genomic characterizations, like The Cancer Genome Atlas (TCGA), have defined mesenchymal subtype in a number of cancer types, such as high-grade serous ovarian cancer and glioblastoma. However, recent analyses have shown that gene expression-based classifications of mesenchymal subtypes often do not associate with poor survival. This "paradox" can be ameliorated using integrated analysis that combines multiple data types. We recently found that integrating mRNA and microRNA (miRNA) data revealed an integrated mesenchymal subtype that is consistently associated with poor survival in multiple cohorts of patients with serous ovarian cancer. This network consists of 8 major miRNAs and 214 mRNAs. Among the 8 miRNAs, 4 are known to be regulators of EMT. This review provides a summary of these 8 miRNAs, which were associated with the integrated mesenchymal subtype of serous ovarian cancer.