METHODS AND COMPOSITIONS FOR THE DIAGNOSIS, CLASSIFICATION, AND TREATMENT OF CANCER

1 .- 198 . (canceled)

199 . A method for evaluating the presence or stage of a cancer in a subject comprising measuring the expression level of a nucleic acid encoding c-Myb or a fragment thereof or the expression level of c-Myb protein or a fragment thereof or the activity of c-Myb protein in a sample obtained from the subject.

200 . The method of claim 199 , further comprising comparing the expression level of said nucleic acid encoding c-Myb or a fragment thereof or the expression level of said c-Myb protein or a fragment thereof or the activity of c-Myb protein in said sample to the level of expression of said nucleic acid encoding c-Myb or a level of expression of c-Myb protein or the activity of c-Myb protein known to be indicative of normal tissue, cancer, or a particular stage of cancer.

201 . The method of claim 200 , wherein an increased level of expression of said c-Myb protein or a fragment thereof or said nucleic acid encoding said c-Myb protein or a fragment thereof or the activity of c-Myb protein indicates the presence or stage of a cancer.

202 . The method of claim 199 , further comprising measuring the expression level of a nucleic acid encoding at least one marker or the expression level of at least one marker protein in addition to the expression level of said nucleic acid encoding c-Myb or a fragment thereof or the expression level of said c-Myb protein or a fragment thereof or the activity of c-Myb protein in said sample.

203 . The method of claim 202 , further comprising comparing the expression level of a nucleic acid encoding at least one marker or the expression level of at least one marker protein in said sample to the expression level of a nucleic acid encoding at least one marker or the expression level of at least one marker protein in normal tissue, tissue from a known cancer, or tissue from a known stage of cancer.

204 . The method of claim 202 , further comprising comparing the expression level of a nucleic acid encoding at least one marker or the expression level of at least one marker protein in said sample to the level of expression of said nucleic acid encoding at least one marker or the expression level of at least one marker protein known to be indicative of normal tissue, cancer or a particular stage of cancer.

205 . The method of claim 202 , wherein the at least one marker is selected from the group consisting of PSA, cyclin A1, cyclin D1, cyclin E1, Bcl-xL, Bcl2, N-cadherin, vimentin, slug, snail, twist, p27/KIP1, p21/WAF1, Bax, and CXCR4.

206 . The method of claim 202 , wherein an increased level of expression of a nucleic acid encoding at least one marker or at least one marker protein indicates the presence or stage of a cancer, wherein the marker is selected from the group consisting of PSA, cyclin A1, cyclin D1, cyclin E1, Bcl-xL, Bcl2, N-cadherin, vimentin, slug, snail, and twist.

207 . The method of claim 202 , wherein decreased level of expression of a nucleic acid encoding at least one marker or at least one marker protein indicates the presence or stage of a cancer, wherein the marker is selected from the group consisting of p27/KIP1, p21/WAF1, Bax, and CXCR4.

208 . The method of claim 199 , wherein the cancer is selected from the group consisting of pancreatic cancer, prostate cancer, castration-resistant prostate cancer, and androgen-dependent prostate cancer.

209 . A method for killing or retarding the growth of at least one cell comprising:

reducing the level of a nucleic acid encoding c-Myb or a fragment thereof or the level of c-Myb protein or a fragment thereof or the activity of c-Myb protein in the cell; and

contacting the cell with an effective amount of a therapeutic compound, wherein the effective amount is reduced compared to a cell wherein the level of a nucleic acid encoding c-Myb or a fragment thereof or the level of c-Myb protein or a fragment thereof or the activity of c-Myb protein is not reduced.

210 . The method of claim 209 , wherein the level of a nucleic acid encoding c-Myb or a fragment thereof or the level of c-Myb protein or a fragment thereof or the activity of c-Myb protein is reduced by contacting the cell with an isolated nucleic acid selected from a small hairpin RNA (shRNA), a small interfering RNA (siRNA), a micro RNA (miRNA), an antisense polynucleotide, and a ribozyme.

211 . The method of claim 210 , wherein the isolated nucleic acid comprises a sequence selected from the group consisting of a sequence encoding c-Myb or a fragment thereof, a sequence encoding antisense c-Myb or a fragment thereof, an antisense nucleic acid complementary to a sequence encoding c-Myb or a fragment thereof, and SEQ ID NO:06.

212 . The method of claim 209 , wherein the therapeutic compound comprises a chemotherapeutic agent.

213 . The method of claim 212 , wherein the chemotherapeutic agent is selected from the group consisting of docetaxel, and paclitaxel.

214 . The method of claim 209 , wherein the at least one cell comprises at least one neoplastic cell selected from the group consisting of a pancreatic cancer cell, a prostate cancer cell, a castration-resistant prostate cancer cell, and an androgen-dependent prostate cancer cell.

215 . A method for reducing the dosage of a therapeutic compound needed to treat a disorder in a subject comprising reducing the level of a nucleic acid encoding c-Myb or the level of c-Myb protein or the activity of c-Myb protein in a cell of the subject.

216 . The method of claim 215 , wherein the level of a nucleic acid encoding c-Myb or the level of c-Myb protein or the activity of c-Myb protein is reduced by contacting the cell with an isolated nucleic acid selected from a small hairpin RNA (shRNA), a small interfering RNA (siRNA), a micro RNA (miRNA), an antisense polynucleotide, and a ribozyme.

217 . The method of claim 216 , wherein the isolated nucleic acid comprises wherein the isolated nucleic acid comprises a sequence selected from the group consisting of a sequence encoding c-Myb or a fragment thereof, a sequence encoding antisense c-Myb or a fragment thereof, an antisense nucleic acid complementary to a sequence encoding c-Myb or a fragment thereof, and SEQ ID NO:06.

218 . The method of claim 215 , wherein the therapeutic compound comprises a chemotherapeutic agent.

219 . The method of claim 218 , wherein the chemotherapeutic agent is selected from the group consisting of docetaxel, and paclitaxel.

220 . The method of claim 215 , wherein the cell comprises a neoplastic cell selected from the group consisting of a pancreatic cancer cell, a prostate cancer cell, a castration-resistant prostate cancer cell, and an androgen-dependent prostate cancer cell.