Search PubMed⌕ Search

Biomedical subjects

Jay R Lieberman

Publications and source records attributed to Jay R Lieberman.

58 records · Page 4Linked to original sources

Use of a SCID mouse model to select for a more aggressive strain of prostate cancer.

BACKGROUND: Prostate cancer is the most common non-cutaneous malignancy to affect men and has a propensity for metastasizing to bone. To better mimic the biology of metastatic prostate cancer, we have developed a model that utilizes both human prostate cancer and human bone in the SCID mouse. MATERIALS AND METHODS: Injection of a xenograft of human prostate cancer, LAPC-4, near a human bone core that was previously implanted within the hindlimb of a SCID mouse allowed for the selection of a more aggressive subset of cells, known as LAPC-4(2) (read as "LAPC-4 squared"). RESULTS: As compared to LAPC-4 cells, these "bone-selected" LAPC-4(2) cells form tumors more rapidly, develop PSA-positive serum at an earlier time-point as well as with higher levels, develop androgen independence, and metastasize to human bone after orthotopic injection. CONCLUSION: The selection of a more aggressive subset of prostate cancer cells that have developed androgen independence and the propensity to metastasize is of paramount importance as these are the cellular characteristics that are clinically linked to morbidity. Analysis of these "bone-selected" cells may lead to a better understanding of the molecular basis behind the conversion of low-grade prostate carcinoma to its more deadly, metastatic form.

Adult↗

The effect of cyclooxygenase-2 (COX-2) inhibition on human prostate cancer induced osteoblastic and osteolytic lesions in bone.

BACKGROUND: The mechanism of bone formation by osteoblastic prostate cancer metastases is not well defined. Using knockout mice, it has been demonstrated that prostaglandins produced by COX-2 are critical for fracture repair. Therefore, our aim was to determine if COX-2 plays a role in the bone formation in osteoblastic prostate cancer metastases in bone. MATERIALS AND METHODS: We assessed the influence of pharmacologic COX-2 inhibition in a SCID mouse intratibial injection model of bone metastasis using two human prostate cancer cell lines that produce either osteoblastic lesions (LAPC-9) or osteolytic lesions (PC-3, negative control). SC-58236, a COX-2 specific inhibitor, was used at a dose of 3 mg/Kg intraperitoneally 3 times per week in the Treatment groups for 8 weeks until sacrifice. RESULTS: Western blot for COX-2 demonstrated that LAPC-9 cells expressed high levels of COX-2 while PC-3 cells did not. Treatment with SC-58236 significantly reduced the size of osteoblastic lesions after LAPC-9 injection based on both radiographic and histomorphometric criteria compared to the control group. In contrast, large osteolytic lesions were seen in both control and SC-58236 treated animals after PC-3 cell injections. The results of this study indicate that COX-2 inhibition can decrease the size of osteoblastic lesions produced by LAPC-9, a human prostate cancer cell line that expresses high levels of COX-2. This treatment had no effect on the osteolytic activity of PC-3 cells. CONCLUSION: These findings suggest that the progression of osteoblastic metastases induced by human prostate cancer cells may be limited by COX-2 inhibitors.

Animals↗