Functional assay for cancer recurrence and malignant potential
Embodiments herein provides an in vitro co-culture system comprising a population of cancer responder cells and a population of non-tumor cells wherein the cancer responder cells can convert to a malignant state and exhibit hallmark malignant phenotype when the cells are placed in a tumor supportive environment. The system is useful for prognosis evaluation of cancer recurrence, malignancy development, cancer drug screening and surveillance for resistance to cancer drug therapy.
1. An assay comprising
in vitro co-culturing a population of cancer responder cells with a population of non-tumor cells in the presence of plasma or platelets or exosomes, wherein the non-tumor cells are selected from the group consisting of bone marrow-derived circulating cells, buffy coat cells, peripheral circulating cells, and immune cells; and
measuring for at least one malignant phenotype exhibited by the cancer responder cells;
wherein at least one of (1) the population of cancer responder cells, (2) the population of non-tumor cells or (3) plasma, platelets, or exosomes is patient-derived and at least one of (1), (2) or (3) are standard positive plasma, platelets, exosomes or cell populations known to provide a tumor supportive environment.
2. The assay of claim 1 , wherein the cancer responder cells are selected from a group consisting of defined cancer responder cell lines, primary cancer/tumor cells, or circulating cancer cells.
3. The assay of claim 1 , wherein the at least one malignant phenotype measured is selected from the group consisting of the ability to proliferate on soft agar, the ability to proliferate and form a tumor in vitro, the ability to proliferate and form a tumor in vivo, the expression of malignancy markers, and the expression of cancer stem cell markers.
4. The assay of claim 1 , further comprising co-culturing the populations of responder cells and non-tumor cells with a population of fibroblast cells.
5. The assay of claim 4 , wherein the population of fibroblast cells is obtained from a healthy, cancer-free tissue from a subject.
6. The assay of claim 4 , wherein the population of fibroblast cells is obtained from a cancer tumor tissue excised from a subject.
7. The assay of claim 4 , wherein the population of fibroblast cells is separated by a membrane from the population of cancer responder cells and the population of non-tumor cells in the co-culture.
8. The assay of claim 1 , further comprising contacting the co-culture with at least a test agent or compound.
9. The assay of claim 1 , wherein the population of cancer responder cells are selected from HME, HMLE, HMLER hygro-H-rasV12 (HMLER-HR), HMLER-puro-H rasV12, BPE, BPLER, BT-549, and MCF7, MCF7-Ras human breast tumor cells.
10. The assay of claim 1 , wherein the cancer responder cells are in an indolent state.
11. The assay of claim 1 , wherein the malignant phenotype exhibited by the cancer responder cells is an increase in expression of Oct4, Oct4A, c-Myc, Zebl, osteopontin, epidermal growth factor receptor (EGFR) and insulin-like growth factor 1 receptor (IGF-1R), or there is
an increase in CD44hi+/CD24low− cells.
12. The assay of claim 1 , wherein the malignant phenotype exhibited by the cancer responder cells is an increase in expression of CD24, or an increase in CD44hi+/CD24low− cells.
13. The assay of claim 1 , wherein the non-tumor cells are obtained from a bone marrow aspirate, a bone marrow biopsy, a spleen biopsy, a blood sample, a lymph node aspirate or biopsy or resection, or a non-tumor portion of a cancer from a patient.