agar and Ascites

The HER2/neu oncogene is overexpressed in up to 70% of human pancreatic cancer specimens when compared to normal pancreatic tissue. This cell surface receptor can be targeted specifically by the neutralizing antibody Herceptin. Herceptin has been successfully used in combination with other chemotherapeutic agents in breast cancer, a cancer in which only 30% of patients harbor elevated HER2/neu levels. In the present study, we investigated the therapeutic efficacy of Herceptin in combination with gemcitabine and docetaxel. Gemcitabine is currently the standard chemotherapeutic agent used to treat pancreatic cancer. In contrast, docetaxel, a taxane, is only just being investigated in pancreatic cancer. Tumor cell resistance to taxanes is at least in part mediated by the HER2/NEU oncogene. We have previously characterized HER2/NEU expression in human pancreatic cancer cell lines and studied the anti-tumor activity of Herceptin monotherapy in vitro and in vivo. In the present study, combination therapy resulted in a dramatic improvement of animals bearing human pancreatic cancer xenografts. Furthermore, metastasis and production of ascites was lower when a combination of these three agents was used. We conclude that, as with breast cancer, the anti-tumor activity of Herceptin may be improved by combination with taxanes or gemcitabine.

Topics: Agar; Animals; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Ascites; Cell Line, Tumor; Cell Survival; Combined Modality Therapy; Deoxycytidine; Docetaxel; Drug Resistance, Neoplasm; Gemcitabine; Humans; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasm Transplantation; Neoplasms, Experimental; Pancreatic Neoplasms; Recombinant Proteins; Taxoids; Time Factors; Trastuzumab

Concurrent Cloning Efficiencies (CE) of both ascites and solid tumor samples from 36 patients with ovarian carcinoma were studied using the soft agar assay. The CE of both were highly variable (range, 0-1.234% and 0-0.802%, respectively). There was marked intrapatient and interpatient heterogeneity in the CE. Of the 36 tested, comparative CE were evaluable in 29. CE was 0 in both solid tumor and ascites in one patient. CE was 0 in four other ascites samples from four patients. In other 24, the relative CE of solid tumor/ascites from each patient ranged from 0.066 to 435. In the 29 patients with samples of ascites and a solid tumor evaluable for concurrent CE, the median colony counts of solid tumors was more than tenfold higher than ascites. The solid tumors obtained from 31 patients had a significantly higher CE than tumor cells obtained from ascites samples from 32 patients. Solid tumors were significantly better than ascites for in vitro testing based on the data that 75% (27/36) of solid tumors and only 31% (11/36) of ascites formed greater than or equal to 30 colonies. The drug sensitivity profiles of tumor cells from a solid tumor and ascites of the same patient appear similar. Based on these observations, it may be more cost and labor effective to do soft agar in vitro chemotherapy assays using a solid tumor than ascites in ovarian carcinoma.

Topics: Agar; Ascites; Carcinoma; Colony-Forming Units Assay; Drug Screening Assays, Antitumor; Female; Humans; Ovarian Neoplasms; Tumor Stem Cell Assay

We studied the factors that control the capacity of tumor cells to grow in soft agar. And, we analyzed the effect of cell-free ascites (CFA) obtained from ovarian cancer patients in combination with various media on the cloning efficiency of H-134 and OVCAR-3nu ovarian carcinoma cell lines and the WiDr colon carcinoma cell line. Seven batches of CFA consistently enhanced the soft agar growth of tumor cells more efficiently than tested sera. The addition of charcoal-treated bovine serum albumin (BSA) lowered the amount of CFA required for optimal tumor cell growth. As little as 1.25 ng of epidermal growth factor (EGF)/ml further improved OVCAR-3nu soft agar growth in combination with all of the amounts of CFA tested. Thus, neither BSA nor EGF seems to account for the colony-stimulating effect of ascites on tumor cells. Four batches of CFA were tested for stimulating soft agar growth of normal rat kidney (NRK-49F) fibroblasts; all induced colonies of different morphologies. This effect was potentiated by EGF, which suggests the presence of several transforming growth factor-like activities in CFA. The results show that differences in cloning efficiency of tumor cells of one or two orders of magnitude can be found between standard (anchorage-dependent growth-supporting) media and media optimalized for soft agar growth, such as CFA in the presence of EGF. This paper will discuss the similarity in effects of CFA on various tumor cells and NRK cells, and possible implications of the stimulatory effects of CFA.

Topics: Agar; Animals; Ascites; Carcinoma; Cell Division; Cells, Cultured; Clone Cells; Colonic Neoplasms; Female; Humans; Neoplastic Stem Cells; Ovarian Neoplasms; Rats

Topics: Agar; Antineoplastic Agents; Ascites; Cell Survival; Cells, Cultured; Clone Cells; Colony-Forming Units Assay; Doxorubicin; Drug Resistance; Female; Humans; Ovarian Neoplasms; Pleural Effusion; Tumor Stem Cell Assay

We studied the in vitro growth characteristics of 10 solid-tumor samples of patients with ovarian carcinoma using a semisolid agar culture technique. Tumor cell colonies were observed in 8 of 10 samples, but sufficient number of tumor colonies to evaluate the effects of interferon and other antitumor agents were obtained in only four samples. As compared with cell suspensions prepared from ascitic fluid samples, solid-tumor samples had markedly lower viability, 39% vs 89%, and had more tumor cells, 81% vs 28%. Also, whereas the maximum increase in tumor-colony number occurred during the first week of growth in both solid- and ascitic-fluid-derived samples grown concurrently from the same donors, increase in tumor colony number was sustained for longer periods in ascitic-fluid-derived cultures. The ascitic-fluid-derived tumor colonies were more sensitive to the antiproliferative effects of interferon than colonies derived from solid-tumors. At a concentration of 300 units/ml incorporated into the agar for the duration of the culture, three of four ascitic fluid samples showed a reduction in tumor colony number by greater than or equal to 25%, whereas none of the solid-tumor samples were affected by the interferon to that degree. In contrast, solid-tumor samples showed greater response to cis platinum and Adriamycin than did ascitic-fluid-derived cultures. Such studies and observations are critical in designing clinical trials for the use of interferon in the treatment of malignancy and the judicious selection of patients and route of administration most likely to provide optimal results, especially in view of present critical shortages in availability of interferon.

Topics: Adult; Agar; Aged; Ascites; Carcinoma; Cisplatin; Clone Cells; Culture Media; Doxorubicin; Female; Humans; Interferons; Middle Aged; Ovarian Neoplasms

Topics: Agar; Animals; Anti-Bacterial Agents; Antineoplastic Agents; Ascites; Carcinoma, Hepatocellular; Clone Cells; Culture Techniques; Diffusion; Liver Neoplasms; Mercaptopurine; Methods; Mitomycins; Neoplasms, Experimental; Nitrogen Mustard Compounds; Rats; Thiotepa

Topics: Adenoviridae; Agar; Animals; Arboviruses; Ascites; Avian Sarcoma Viruses; Cricetinae; Encephalitis Viruses; Encephalomyocarditis virus; Enterovirus; Enterovirus B, Human; Forests; Herpesviridae; In Vitro Techniques; Influenza A virus; Neoplasms; Neoplasms, Experimental; Orthomyxoviridae; Paramyxoviridae Infections; Poliovirus; Polyomavirus; Rabies virus; Reoviridae; Research; Rous sarcoma virus; Semliki forest virus; Sendai virus; Simplexvirus; Tissue Culture Techniques; Vaccinia virus; Vertebrates; Virus Cultivation; Viruses

Topics: Agar; Antineoplastic Agents; Ascites; Humans; Neoplasms