Conditionally reprogrammed normal and primary tumor prostate epithelial cells: a novel patient-derived cell model for studies of human prostate cancer.

Olga Timofeeva ,Hang Yuan,Nancy Palechor-Ceron,Guanglei Li,Songtao Yu,Andrew Ju,Anatoly Dritschilo,Ewa Krawczyk,Yong Hou,Shuang Fang,Geeta Upadhyay,Xueping Zhang,Xiaogang Zhong,Youngmi Ji,Myeong-Seon Lee,Chris Albanese,Richard Schlegel,Yun‐Ling Zheng ,Johng S Rhim ,Aleksandra Dakić ,Geng Li ,Sujata Maiti Choudhury ,Dong Han ,Xuefeng Li

doi:10.18632/oncotarget.13937

Abstract

Our previous study demonstrated that conditional reprogramming (CR) allows the establishment of patient-derived normal and tumor epithelial cell cultures from a variety of tissue types including breast, lung, colon and prostate. Using CR, we have established matched normal and tumor cultures, GUMC-29 and GUMC-30 respectively, from a patient's prostatectomy specimen. These CR cells proliferate indefinitely in vitro and retain stable karyotypes. Most importantly, only tumor-derived CR cells (GUMC-30) produced tumors in xenografted SCID mice, demonstrating maintenance of the critical tumor phenotype. Characterization of cells with DNA fingerprinting demonstrated identical patterns in normal and tumor CR cells as well as in xenografted tumors. By flow cytometry, both normal and tumor CR cells expressed basal, luminal, and stem cell markers, with the majority of the normal and tumor CR cells expressing prostate basal cell markers, CD44 and Trop2, as well as luminal marker, CD13, suggesting a transit-amplifying phenotype. Consistent with this phenotype, real time RT-PCR analyses demonstrated that CR cells predominantly expressed high levels of basal cell markers (KRT5, KRT14 and p63), and low levels of luminal markers. When the CR tumor cells were injected into SCID mice, the expression of luminal markers (AR, NKX3.1) increased significantly, while basal cell markers dramatically decreased. These data suggest that CR cells maintain high levels of proliferation and low levels of differentiation in the presence of feeder cells and ROCK inhibitor, but undergo differentiation once injected into SCID mice. Genomic analyses, including SNP and INDEL, identified genes mutated in tumor cells, including components of apoptosis, cell attachment, and hypoxia pathways. The use of matched patient-derived cells provides a unique in vitro model for studies of early prostate cancer.

Highlights

Prostate cancer is the most frequently diagnosed solid malignancy in American men with an estimated 220,800 new cases and 27,540 deaths in 2015 [1]
These data suggest that conditional reprogramming (CR) cells maintain high levels of proliferation and low levels of differentiation in the presence of feeder cells and ROCK inhibitor, but undergo differentiation once injected into SCID mice
Cells of non-malignant and malignant regions of a prostatectomy specimen were grown in keratinocyte serum-free medium (K-SFM) and transferred to CR conditions to generate immortalized cultures as previously described [8]

Summary

Introduction

Prostate cancer is the most frequently diagnosed solid malignancy in American men with an estimated 220,800 new cases and 27,540 deaths in 2015 [1]. Development of a PDX model can take anywhere from 2 to 12 months with engraftment rates typically from 2% to 50% depending on the tumor type This limits the ability to use such cancer cell lines and PDXs for predicting responses to drug-, radiation-, or immuno-therapies. Progress in the field has been hindered by the absence of appropriate models of humanderived prostate cancer cells, precluding investigation of transforming alterations and development of treatment approaches. For this reason, primary cultures of malignant prostatic cells and normal, preferably donor-matched, epithelial counterparts grown under identical conditions are needed

Methods

Results

Conclusion