Innovative In Vitro Chemo-Hormonal Drug Therapy for Refractory Thyroid Carcinomas

More than 95% of the thyroid carcinomas are well differentiated types showing favorable prognosis. However, only a few therapeutic options are available to treat the patients with undifferentiated thyroid carcinomas, especially with refractory thyroid carcinomas that are not amenable to surgery or radioiodine ablation. We investigated the anticancer effects of 20 chemotherapy and hormonal therapy drugs on 8 thyroid carcinoma cell lines. In vitro chemosensitivity was tested using the adenosine-triphosphate-based chemotherapy response assay (ATP-CRA). The tumor inhibition rate (TIR; or cell death rate) or half maximal inhibitory concentration (IC50) was analyzed to interpret the results. Of the 12 chemotherapy drugs, etoposide (178.9 index value in follicular carcinoma cell line) and vincristine (211.7 in Hurthle cell carcinoma cell line) were the most active drugs showing the highest chemosensitivity, and of the 8 additional drugs, trichostatin A (0.03 microg/mL IC50 in follicular carcinoma cell line) showed favorable outcome having the anticancer effect. In our study, the result of etoposide and vincristine show evidence as active anticancer drugs in thyroid carcinoma cell lines and trichostatin A seems be the next promising drug. These drugs may become an innovative therapy for refractory thyroid carcinomas in near future.

Preliminary Study of the Clinical Features of the Chemosensitivity Test in Colorectal Cancer

PURPOSE: Colorectal cancers have been known to be refractory to chemotherapy in the past decades. Recently, novel agents have been developed and various data have shown an improved response rate and a survival benefit. However, considerable heterogeneity exists between cancers of the same tissue type, including colorectal cancer. Thus, Individualized chemotherapy that is tailored specifically to the characteristics of the tumor is necessary for an improved clinical outcome. RESULTS: We evaluate the chemosensitivity of colorectal cancer to standard drugs (5-FU, oxaliplatin, and irinotecan) and to drugs used for other cancers (mitomycin, paclitaxel, and gemcitabine) by using Adenosine-triphosphate-based chemotherapy response assay (ATP-CRA). RESULTS: The degree of in-vitro response to a single anticancer medication was highest for 5-FU. According to stages, 5-FU is the most sensitive chemotherapeutic agent in Duke's B, irinotecan in Duke's C, and 5-FU in Duke's D patients. With tumor location, irinotecan is most sensitive in colon cancers and 5-FU in rectal cancers. The effect of treatment is superior in the test-guided therapy group in Duke's D colorectal cancer patients. CONCLUSIONS: Chemosensitivity tests may be useful in selecting optimum drugs for patient who require chemotherapy. However, the results of this study do not strongly support the usefulness of this assay; further studies with a sufficient number of cases and an extended observation period are ongoing.

In-vitro Chemosensitivity Test for Colorectal Cancer using an Adenosine-triphosphate-based Chemotherapy Response Assay (ATP-CRA)

Purpose: The adenosine-triphosphate-based chemotherapy response assay (ATP-CRA) is a well-documented and validated technology for individualizing chemotherapy in cancer patients. We evaluate the feasibility of ATP-CRA in colorectal cancer patients. This study will illustrate the assay's success rate, the mean coefficient of variation, and the turnaround time as a validation tool for a chemosensitivity test. Methods: A total of 118 patients, treated by surgery between June 2004 and September 2005 were evaluated for chemosensitivity to seven anticancer agents (5-fluorouracil (5-FU), oxaliplatin, irinotecan, epirubicin, etoposide, gemcitabine, and paclitaxel) by using an ATP-CRA. To allow a comparison between samples, we calculated the chemosensitivity index (CI) based on the percentage cell death rate (CDR, %) at each test drug concentration. Results: The assay success rate was 85.5% (118/138), and the mean coefficient of variation, indicating intra-assay error level, was 9.2%. CDR measured at a therapeutic peak plasma concentration ranged from 0% to 93.6% with a median of 31.0% for 5-FU, 28.5% for oxaliplatin, 34.0% for irinotecan, 25.0% for epirubicin, 21.0% for etoposide, 22.0% for gemcitabine, and 25.2% for paclitaxel. According to the CI, the most sensitive drug varied from patient to patients 10.9% for 5-FU, 10.9% for oxaliplatin, 24.7% for irinotecan, 11.8% for epirubicin, 22.4% for etoposide, 1.1% for gemcitabine, and 23.3% for paclitaxel. Conclusions: Our data suggest that the ATP- CRA is a feasible in-vitro chemosensitivity test in colorectal cancer and that patients show heterogeneous chemosensitivity. A study evaluating the predictive value of ATP-CRA directed therapy is needed to determine the clinical usefulness of the test.

A Feasibility Study of Adenosine Triphosphate-based Chemotherapy Response Assay (ATP-CRA) as a Chemosensitivity Test for Lung Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: A chemosensitivity test can reflect the differences in responses of individual cancer patients to chemotherapeutic agents. The adenosine triphosphate-based chemotherapy response assay (ATP-CRA)is an accurate method, which does not require a large amount of tissue specimen. So far, no studies have evaluated the utility of the ATP-CRA in Korea. Therefore, we investigated the clinical usefulness of the ATP-CRA in 53 patients with lung cancer. MATERIALS AND METHODS: Tumor tissues were obtained from bronchoscopic biopsies or surgical resections. The validity of ATP-CRA was assessed focusing on the success rate, experimental error level (intraassay mean coefficient of variation [CV]) and reproducibility. RESULTS: The overall success rate of ATP-CRA was 90.6% (48/53). Normal cells were effectively eliminated from the tumor tissues with the use of ficoll gradient centrifugation and immunomagnetic separation, which was confirmed using loss of heterozygosity analysis of the 3p deletion. The mean CV of ATP assays was 10.5+/-4.6%. The reproducibility of ATP assays was 94+/-3.8%. The results of the ATP assays were reported to physicians within 7 days of specimen collection. More than 6 anticancer drugs were tested on the tumor specimens obtained from bronchoscopic biopsies. CONCLUSION: The ATP-CRA is a stable, accurate and potentially practical chemosensitivity test in patients with lung cancer.