Cultured cell lines from human breast cancer biopsies and xenografts

Explant-cell culture of primary mammary tumors from MMTV-c-Myc transgenic mice

We have established an explant-cell culture system for mammary gland tumors from c-myc oncogene-expressing transgenic mice and potentially other transgenic strains. By coating culture dish surfaces with fetal bovine serum and using culture media supplemented with low serum and growth factors, the mammary tumor specimens could be maintained in culture for over 3 mo. Throughout the culture period, the explants produced abundant outgrowths of epithelial cells. As the outgrowths of epithelial cells filled the dishes, the explants were serially transferred from one dish to another-a process that could be repeated at least six times, thus providing a continuous supply of primary tumor cells. This culture system provides a useful tool for studying the biology of mouse mammary gland tumors and possibly tumors from other organ sites.

Growth of tumor-derived activated T cells for the treatment of advanced cancer

In 1994, we reported on a series of patients treated with T-cell therapy (Study #1). This paper (Study #2) is an update of our experience through 1999 in the production of tumor-derived activated cells (TDAC), also called tumor-infiltrating lymphocytes (TIL), from tumor biopsies. TDAC were successfully grown in medium containing Interleukin-2 from 75% of the 366 tumor biopsies tested. There was no significant difference in success (growth to 1 x 10(9) cells) comparing primary and metastatic tumors. Many of the tumors were shipped to the laboratory by overnight delivery from distant sites. Success rate did decrease with the length of time for tumor transport in excess of 24 hours. Certain additional cytokines were tested when cultures did not grow. Interleukin-4 was beneficial in the development of 1 of 4 TDAC cultures which did not grow with IL-2 alone. In order to produce TDAC to treat patients, cells were grown in gas permeable plastic bags or in artificial capillary bioreactor cultures. Approximately 1 x 10(9) were seeded from an initially successful "feasibility study" to bulk produce cells for treatment. Harvest was carried out after about 3 weeks. Sixty-three patients were treated at least once with a minimum of 1 x 10(10) TDAC given by intravenous infusion. On the average, the number of cells per treatment was 3 x 10(10) with a viability of 87%. TDAC cultures contained T cells with variable ratios of CD4 to CD8 cells. Secreted granulocyte-monocyte colony stimulating factor, interferon gamma and tumor necrosis factor alpha were measured in TDAC conditioned medium. Only 34 patients received the full course of 4 TDAC treatments. The cells were well tolerated with mild fever and dyspnea. Partial responses were observed in 8 patients, including the dramatic regression of scalp nodules in a patient with renal cancer. These results showed that therapeutic amounts of TDAC can be produced in cell culture in a reasonable and cost-effective manner. The cells were well tolerated and responses were seen in renal and melanoma patients resistant to IL-2 with bulky, advanced cancer.

Site-specific experimental metastasis patterns of two human breast cancer cell lines in nude rats

Animal models for breast cancer metastasis are valuable tools for studying mechanisms of metastasis and for preclinical testing of anti-metastatic therapy regimens. Using MA-11 and MT-1, two oestrogen and progesterone receptor-negative human breast cancer cell lines, we developed new models in nude rats with patterns of experimental metastasis resembling those frequently observed in humans. MA-11 cells showed a clear preference for growth in the CNS. Fourteen of 15 animals injected with MA-11 cells into the left ventricle of the heart developed hind-leg paralysis, and tumours were observed in the spinal cord. MT-1 cells consistently exhibited bone/bone marrow metastases after intracardial injection, in addition to tumours in the brain and spinal cord. When injected into the cisterna magna, both cell lines gave rise to leptomeningeal neoplastic disease. Injection of MA-11 cells into the tibial bone marrow resulted in tumours in only 2 of 13 rats, whereas all animals injected with MT-1 cells developed tumours. Only 2 of 6 rats injected i.v. with MA-11 cells developed lung colonies compared with all 9 animals injected with MT-1 cells. Cell-surface expression of the following was examined: EGP2; MUC1; EGFr; E- and N-cadherin; the alpha2, alpha3, alpha5, beta1 and beta4 integrins; c-erb-B2; and N-CAM. c-erb-B2 was expressed in a higher percentage of the bone-metastasizing MT-1 cells than the MA-11 cells, whereas E-cadherin was expressed in MA-11 but not MT-1 cells. In animals injected with MA-11 and MT-1 cells in the left cardiac ventricle, treatment with cisplatin and doxorubicin did not improve survival. In summary, these clinically relevant animal models may be used for studies related to site-specific growth and metastasis and for assessing effects of experimental therapy against human breast cancer.

Growth of tumor derived activated T-cells for the treatment of cancer

This report describes the production of Tumor Derived Activated Cell cultures (TDAC, also called tumor infiltrating lymphocytes) from patient tumor biopsies and our preliminary experience growing these cells to therapeutic levels using artificial capillary bioreactor cultures. TDAC were successfully grown in medium containing Interleukin 2 from 80% of the 113 tumor biopsies tested. There was no significant difference in success (growth to 1 x 10(9) cells) comparing primary and metastatic tumors. Many of the tumors were shipped to the laboratory from distant sites. Success rate did decrease with the length of time for tumor transport. Interleukin 4 was beneficial in the development of 1 of 4 TDAC cultures which did not grow with IL-2 only. Seventy-seven bioreactor cultures were initiated for 31 patients. On the average, 1.9 x 10(9) TDAC were inoculated per bioreactor; 3.3 x 10(10) were harvested in 22 days. Twelve liters of medium were required per 1 x 10(10) TDAC produced. TDAC cultures contained T cells with variable ratios of CD4 to CD8 cells. Secreted granulocyte monocyte colony stimulating factor, interferon gamma and tumor necrosis factor were measured in the bioreactor cartridge conditioned medium. Twenty three patients were evaluated. Partial responses were observed in 4 patients including a dramatic remission of scalp nodules in a patient with renal cancer. Results showed that therapeutic amounts of TDAC cells may be produced in a reasonable and cost effective manner using artificial capillary bioreactor cultures.

Cultured breast cystosarcoma phylloides cells and applications to patient therapy

Malignant cystosarcoma phylloides (CP) is a relatively rare cancer of the breast. A CP tumor was processed as part of a tumor acquisition, propagation, and preservation program in patient biotherapy. Two tissue culture cell lines were developed from this tumor, one directly from the biopsy, another from a xenograft tumor grown in athymic mice. The two cell lines were similar in character. There was strong immunochemical reactivity with antibodies to vimentin, type I collagen, and type III collagen. There was no reactivity with antibodies to cytokeratin and epithelial membrane antigen. Both cell lines were aneuploid, clonogenic in soft agar, and tumorigenic in nude mice. 5 alpha-dihydrotestosterone and thyroxine added to the culture medium stimulated growth, while testosterone, 17 beta-estradiol, and 4-hydroxytamoxifen were without effect. Dexamethasone and cortisol were inhibitory at high doses (10(-6) M). Dibutyryl cyclic AMP, theophylline, and vitamin C were all inhibitory. The biopsy contained tumor-infiltrating lymphocytes which proliferated in cultures containing interleukin 2. The expanded lymphocytes were activated T cells which had the capacity to lyse tumor cells. These results suggest possibilities in the therapy of cystosarcoma phylloides involving vitamin C, certain hormones, and tumor-infiltrating lymphocytes.