Modeling Spontaneous Bone Metastasis Formation of Solid Human Tumor Xenografts in Mice

Abstract

The majority of cancer-related deaths are due to hematogenous metastases, and the bone marrow (BM) represents one of the most frequent metastatic sites. To study BM metastasis formation in vivo, the most efficient approach is based on intracardiac injection of human tumor cells into immunodeficient mice. However, such a procedure circumvents the early steps of the metastatic cascade. Here we describe the development of xenograft mouse models (balb/c rag2-/- and severe combined immunodeficient (SCID)), in which BM metastases are spontaneously derived from subcutaneous (s.c.) primary tumors (PTs). As verified by histology, the described methodology including ex vivo bioluminescence imaging (BLI) even enabled the detection of micrometastases in the BM. Furthermore, we established sublines from xenograft primary tumors (PTs) and corresponding BM (BM) metastases using LAN-1 neuroblastoma xenografts as a first example. In vitro “metastasis” assays (viability, proliferation, transmigration, invasion, colony formation) partially indicated pro-metastatic features of the LAN-1-BM compared to the LAN-1-PT subline. Unexpectedly, after s.c. re-injection into mice, LAN-1-BM xenografts developed spontaneous BM metastases less frequently than LAN-1-PT xenografts. This study provides a novel methodologic approach for modelling the spontaneous metastatic cascade of human BM metastasis formation in mice. Moreover, our data indicate that putative bone-metastatic features get rapidly lost upon routine cell culture.

CHD1 loss negatively influences metastasis-free survival in R0-resected prostate cancer patients and promotes spontaneous metastasis in vivo

“…This finding implies that CHD1 suppresses metastatic outgrowth. Metastasis to other sites such as bone marrow can only rarely be found at a very low level in spontaneous metastasis xenografts and requires several modifications of the methodology [26]. As of yet, potential effects of the CHD1 loss on bone metastasis were therefore not determined, which is a limitation of this study.…”

The distinct role of ALDH1A1 and ALDH1A3 in the regulation of prostate cancer metastases

“…To further investigate the role of ALDH genes in metastasis, we measured the expression of ALDH1A1 and ALDH1A3 genes in the PC3 cells originating from different metastatic sites (Labitzky et al, 2020). Briefly, PC3 cells were first subcutaneously injected into immunodeficient NSG mice, and small pieces of surgically excised xenograft tumors (PT), as well as spontaneous lung (L) and bone marrow (BM) metastases were used for in vitro propagation of sublines PC3-PT, PC3-L, and PC-BM, respectively (Fig.…”

Immune characterization of pre-clinical murine models of neuroblastoma

“…Here, we present data comparing the most widely used immunocompetent murine models and their ability to model human NB disease. However, xenograph models, using human tissue or cell lines are another model which can be utilized 15 , 36 , 53 – 56 . Until recently these models mainly used immunompromised mice and therefore it would be difficult to study tumor immunology and immunotherapeutics.…”