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Epithelial/mesenchymal heterogeneity of high-grade serous ovarian carcinoma samples correlates with miRNA let-7 levels and predicts tumor growth and metastasis.

ABSTRACT: Patient-derived samples present an advantage over current cell line models of high-grade serous ovarian cancer (HGSOC) that are not always reliable and phenotypically faithful models of in vivo HGSOC. To improve upon cell line models of HGSOC, we set out to characterize a panel of patient-derived cells and determine their epithelial and mesenchymal characteristics. We analyzed RNA and protein expression levels in patient-derived xenograft (PDX) models of HGSOC, and functionally characterized these models using flow cytometry, wound healing assays, invasion assays, and spheroid cultures. Besides in vitro work, we also evaluated the growth characteristics of PDX in vivo (orthotopic PDX). We found that all samples had hybrid characteristics, covering a spectrum from an epithelial-to-mesenchymal state. Samples with a stronger epithelial phenotype were more active in self-renewal assays and more tumorigenic in orthotopic xenograft models as compared to samples with a stronger mesenchymal phenotype, which were more migratory and invasive. Additionally, we observed an inverse association between microRNA let-7 (lethal-7) expression and stemness, consistent with the loss of let-7 being an important component of the cancer stem cell phenotype. We observed that lower let-7 levels were associated with the epithelial state and a lower epithelial mesenchymal transition (EMT) score, more efficient spheroid and tumor formation, and increased sensitivity to platinum-based chemotherapy. Surprisingly, in these HGSOC cells, stemness could be dissociated from invasiveness: Cells with lower let-7 levels were more tumorigenic, but less migratory, and with a lower EMT score, than those with higher let-7 levels. We conclude that let-7 expression and epithelial/mesenchymal state are valuable predictors of HGSOC proliferation, in vitro self-renewal, and tumor burden in vivo.

SUBMITTER: Chirshev E

PROVIDER: S-EPMC7607177 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Epithelial/mesenchymal heterogeneity of high-grade serous ovarian carcinoma samples correlates with miRNA let-7 levels and predicts tumor growth and metastasis.

Chirshev Evgeny E Hojo Nozomi N Bertucci Antonella A Sanderman Linda L Nguyen Anthony A Wang Hanmin H Suzuki Tise T Brito Emmanuel E Martinez Shannalee R SR Castañón Christine C Mirshahidi Saied S Vazquez Marcelo E ME Wat Pamela P Oberg Kerby C KC Ioffe Yevgeniya J YJ Unternaehrer Juli J JJ

Molecular oncology 20200821 11

Patient-derived samples present an advantage over current cell line models of high-grade serous ovarian cancer (HGSOC) that are not always reliable and phenotypically faithful models of in vivo HGSOC. To improve upon cell line models of HGSOC, we set out to characterize a panel of patient-derived cells and determine their epithelial and mesenchymal characteristics. We analyzed RNA and protein expression levels in patient-derived xenograft (PDX) models of HGSOC, and functionally characterized the ...[more]

PMID: 32652647

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Dataset Information

Epithelial/mesenchymal heterogeneity of high-grade serous ovarian carcinoma samples correlates with miRNA let-7 levels and predicts tumor growth and metastasis.

Publications

Epithelial/mesenchymal heterogeneity of high-grade serous ovarian carcinoma samples correlates with miRNA let-7 levels and predicts tumor growth and metastasis.

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