Canine prostatic cancer cell line (LuMa) with osteoblastic bone metastasis

Abstract

Background: Osteoblastic bone metastasis represents the most common complication in men with prostate cancer (PCa). During progression and bone metastasis, PCa cells acquire properties similar to bone cells in a phenomenon called osteomimicry, which promotes their ability to metastasize, proliferate, and survive in the bone microenvironment. The mechanism of osteomimicry resulting in osteoblastic bone metastasis is unclear. Methods:We developed and characterized a novel canine prostatic cancer cell line (LuMa) that will be useful to investigate the relationship between osteoblastic bone metastasis and osteomimicry in PCa. The LuMa cell line was established from a primary prostate carcinoma of a 13-year old mixed breed castrated male dog. Cell proliferation and gene expression of LuMa were measured and compared to three other canine prostatic cancer cell lines (Probasco, Ace-1, and Leo) in vitro. The effect of LuMa cells on calvaria and murine preosteoblastic (MC3T3-E1) cells was measured by quantitative reverse-transcription polymerase chain reaction and alkaline phosphatase assay. LuMa cells were transduced with luciferase for monitoring in vivo tumor growth and metastasis using different inoculation routes (subcutaneous, intratibial [IT], and intracardiac [IC]). Xenograft tumors and metastases were evaluated using radiography and histopathology. Results: After left ventricular injection, LuMa cells metastasized to bone, brain, and adrenal glands. IT injections induced tumors with intramedullary new bone formation. LuMa cells had the highest messenger RNA levels of osteomimicry genes (RUNX2, RANKL, and Osteopontin [OPN]), CD44, E-cadherin, and MYOF compared to Ace-1, Probasco, and Leo cells. LuMa cells induced growth in calvaria defects and modulated gene expression in MC3T3-E1 cells. Conclusions: LuMa is a novel canine PCa cell line with osteomimicry and stemness properties. LuMa cells induced osteoblastic bone formation in vitro and in vivo.LuMa PCa cells will serve as an excellent model for studying the mechanisms of osteomimicry and osteoblastic bone and brain metastasis in prostate cancer. K E Y W O R D Sbone, canine, dog, metastasis, osteoblast, prostate cancer, tumor

Stimulation of in vitro bone formation by canine prostate cancer

“…BMP-2 mediates extracellular matrix mineralization by osteoblasts partly through the induction of a WNT autocrine/paracrine loop [26] . BMP-2 is highly expressed in Probasco cells compared to Ace-1 cells [7] . Secreted BMP-2 in Probasco CM could be an important factor stimulating bone mineralization and the markedly increased ALP activity in CM treated-calvaria.…”

“…Four canine prostatic cancer cell lines were used in this study including Ace-1 [6] , Probasco [7] , Probasco+DKK-1 (Probasco cells transduced with human DKK-1), and LuMa [8] (all cells were established by our laboratory). Cells were cultured in DMEM/F12 (Gibco, Carlsbad, CA) containing 10% fetal bovine serum (FBS), 1% penicillin/streptomycin and 100 μg/mL Normocin (Invivogen, San Diego, CA).…”

“…Our laboratory has developed multiple prostate cancer cell lines from spontaneous prostate cancer in dogs. This investigation utilized three different cell lines (Ace- [6] , Probasco [7] , and LuMa [8] ) that vary in their in vivo phenotype in athymic mice. All metastasize to bone and induce different degrees of osteoblastic bone formation and osteoclastic bone resorption.…”

Comparative pathology of dog and human prostate cancer

“…Of PCa seen in dogs, prostatic glandular and urothelial (transitional cell) carcinoma are the most common cancers arising from prostatic acini and urethra, respectively (Smith, 2008 ). In the recent years, canine PCa cell lines, including from brain metastases, have been successfully derived from dogs with spontaneous PCa (Elshafae et al., 2020 ; Packeiser et al., 2020 ; Simmons et al., 2014 ; Thudi et al., 2011 ), enabling a better understanding of the molecular characteristics of the disease in dogs.…”

Forkhead box F2 as a novel prognostic biomarker and potential therapeutic target in human cancers prone to bone metastasis: a meta-analysis

“…[3][4][5][6][7] In contrast, osteoblastic metastases, characterized by excessive bone formation, are found predominantly in prostate cancer. 8 Despite advances in surgical treatment and adjuvant techniques, the prognosis for tumours that are prone to form bone metastases remains poor. 9 The Forkhead box (FOX) transcription factor family represents a group of genetically conserved transcriptional regulators that play important roles in both healthy biological functions and tumour progression, such as invasion, differentiation and development.…”