Culture Drug Sensitivity Test Research Articles

Stratified phase II trial to establish the usefulness of the collagen gel droplet embedded culture-drug sensitivity test (CD-DST) for advanced gastric cancer

BackgroundWe conducted a multicenter phase II trial to assess the suitability of three types of chemotherapy (docetaxel plus S-1, irinotecan plus S-1, or S-1 alone) for patients with advanced gastric cancer by means of the collagen gel droplet embedded culture-drug sensitivity test (CD-DST). To our knowledge, this is the first multicenter clinical trial that has employed CD-DST to choose anticancer agents for the treatment of advanced gastric cancer.MethodsSubjects (n = 64) were patients with advanced or recurrent gastric cancer. Patients were allocated to one of the treatment regimens on the basis of CD-DST results. Outcome of the patients was compared between the groups deemed chemosensitive or chemoresistant by the CD-DST.ResultsThirty-three patients showed high sensitivity (T/C ratio <60 %) to at least one type of anticancer agent (sensitive group), and 31 showed low sensitivity (T/C ratio ≥60 %) to all agents (resistant group). Specifically, the 1-year survival rate was significantly higher in the sensitive group (78.5 %; 95 % CI, 67.2–94.7 %) than in the resistant group (54.7 %; 95 % CI, 38.7–74.3 %; P = 0.019), whereas time to progression (TTP) was significantly longer in the sensitive group (59.8 %; 95 % CI, 48.2–81.7 %) than in the resistant group (30.0 %; 95 % CI 13.6–46.4 %; P = 0.023). Median survival time was also significantly longer in the sensitive group (15.5 months; 95 % CI, 12.8–18.2) than in the resistant group (12.5 months; 95 % CI, 10.2–14.9; P = 0.038).ConclusionsCD-DST predicts the outcome of patients undergoing chemotherapy for advanced gastric cancer, presumably through evaluating chemosensitivity.

Protein-bound polysaccharide-K augments the anticancer effect of fluoropyrimidine derivatives possibly by lowering dihydropyrimidine dehydrogenase expression in gastrointestinal cancers

Protein-bound polysaccharide-K (PSK) enhances the antitumor effect of anticancer drug when used clinically in combination with such drugs. PSK is known to act by immune-mediated mechanisms; however, the relationship between PSK and metabolic enzymes of anticancer drugs is unknown. We used the collagen gel droplet-embedded culture drug sensitivity test (CD-DST) clinically to evaluate the sensitivity of anticancer drugs. In the present study, we modified the CD-DST by adding peripheral blood mononuclear cells (PBMCs) (immuno-CD-DST) and examined the antitumor effect of PSK in combination with anticancer drugs. First, HCT116 human colon cancer cells were cultured with PSK and 5-fluorouracil (5-FU) or 5'-deoxy-5-fluorouridine (5'-DFUR) in the presence or absence of PBMCs, and the antiproliferative effects were compared. In the presence of PBMCs, PSK augmented the inhibitory effects of 5-FU and 5'-DFUR on HCT116 cell proliferation. Next, using human gastric cancer and colon cancer cell lines, the effects of PSK on mRNA expression of various metabolic enzymes of fluoropyrimidines: dihydropyrimidine dehydrogenase (DPD), thymidylate synthase, thymidine phosphorylase and orotate phosphoribosyl transferase, were examined by real-time PCR. PSK significantly enhanced DPD mRNA expression in all of the cancer cell lines tested, but not those of the other enzymes. Addition of IFN-α and TRAIL, cytokines known to inhibit DPD expression, to the cultures reduced DPD mRNA expression in the cancer cells. When PBMC samples collected from healthy volunteers were cultured with PSK, IFN-α mRNA expression increased in 3 of the 5 PBMC samples, while TRAIL mRNA expression was unchanged. The present results propose the possibility that PSK induces PBMCs to express IFN-α which inhibits DPD expression, and consequently augments the antitumor effect of 5-FU or 5'-DFUR. Immuno-CD-DST is useful for evaluating drugs with immunological mechanisms of action.

Differences in Chemosensitivity between Primary and Metastatic Tumors in Colorectal Cancer

PurposeWe retrospectively evaluated the in vitro chemosensitivity of primary site and metastatic site tumors in colorectal cancer.MethodsVarious resected tumor samples (33 from lymph nodes, 42 from liver, six from lung, and 68 primary tumors) were assessed via a collagen gel droplet-embedded culture drug sensitivity test to determine chemosensitivity to a single agent or a combination of agents.ResultsSensitivity to combination chemotherapy was significantly higher than that of monotherapy in the primary site group, lymph node group, and liver group. There was significant difference between chemosensitivity of primary site and that of liver metastasis in each agent (5-FU, p<0.001; SN38, p = 0.045; 5-FU/SN38, p<0.001; OHP, p = 0.037; 5-FU/OHP, p = 0.045).ConclusionsTumors showed greater in vitro chemosensitivity to combination therapy when compared with monotherapy. Further, tumors that had metastasized to the liver were more resistant to chemotherapy when compared with matched primary tumors.

Comparison of laboratory costs of rapid molecular tests and conventional diagnostics for detection of tuberculosis and drug-resistant tuberculosis in South Africa

BackgroundThe World Health Organization has endorsed the use of molecular methods for the detection of TB and drug-resistant TB as a rapid alternative to culture-based systems. In South Africa, the Xpert MTB/Rif assay and the GenoType MTBDRplus have been implemented into reference laboratories for diagnosis of TB and drug-resistance, but their costs have not been fully elucidated.MethodsWe conducted a detailed reference laboratory cost analysis of new rapid molecular assays (Xpert and MTBDRplus) for tuberculosis testing and drug-resistance testing in South Africa, and compared with the costs of conventional approaches involving sputum microscopy, liquid mycobacterial culture, and phenotypic drug sensitivity testing.ResultsFrom a laboratory perspective, Xpert MTB/RIF cost $14.93/sample and the MTBDRplus line probe assay cost $23.46/sample, compared to $16.88/sample using conventional automated liquid culture-based methods. Laboratory costs of Xpert and MTBDRplus were most influenced by cost of consumables (60-80%).ConclusionsAt current public sector pricing, Xpert MTB/RIF and MTBDRplus are comparable in cost to mycobacterial culture and conventional drug sensitivity testing. Overall, reference laboratories must balance costs with performance characteristics and the need for rapid results.

Clinical potential of the anticancer drug sensitivity test for patients with synchronous stage IV colorectal cancer

We retrospectively evaluated the clinical efficacy and feasibility of a collagen gel droplet-embedded culture drug sensitivity test (CD-DST) to guide therapy for patients with stage IV colorectal cancer (CRC). We investigated 38 patients with stage IV CRC. All patients were younger than 85 years and had untreated evaluable metastatic lesions. The primary tumors were surgically resected, and the tissue samples were investigated by CD-DST. Patients treated with in vitro sensitive drugs were defined as Group A (n = 14), while those treated with in vitro non-sensitive drugs were defined as Group B (n = 24). We evaluated response rate (RR), progression-free survival (PFS), and overall survival (OS). RR was 85.71 % in Group A and 41.67 % in Group B (p = 0.0079). The median PFS was 696.5 days in Group A and 297.5 days in Group B (p = 0.0326). The median OS was 1,023.4 days in Group A and 518.5 days in Group B (p = 0.0061). The CD-DST can define chemoresistant and chemosensitive tumors. The use of CD-DST might be one of the tools to supplement informed consent prior to initiation of therapy.

Comparison of Mycobacterium tuberculosis drug susceptibility using solid and liquid culture in Nigeria

BackgroundThis study compares Mycobacterium tuberculosis culture isolation and drug sensitivity testing (DST) using solid (LJ) and liquid (BACTEC-MGIT-960) media in Nigeria.MethodsThis was a cross sectional survey of adults attending reference centres in Abuja, Ibadan and Nnewi with a new diagnosis of pulmonary tuberculosis (TB) or having failed the first-line TB treatment. Patients were requested to provide three sputum specimens for smear-microscopy and culture on LJ and BACTEC-MGIT-960. Positive cultures underwent DST for streptomycin, isoniazid, rifampicin and ethambutol.Results527 specimens were cultured. 428 (81%) were positive with BACTEC-MGIT-960, 59 (11%) negative, 36 (7%) contaminated and 4 (1%) had non-tuberculosis mycobacteria (NTM). 411 (78%) LJ cultures were positive, 89 (17%) negative, 22 (4%) contaminated and 5 (1%) had NTM. The mean (SD) detection time was 11 (6) and 30 (11) days for BACTEC-MGIT-960 and LJ. DST patterns were compared in the 389 concordant positive BACTEC-MGIT-960 and LJ cultures. Rifampicin and isoniazid DST patterns were similar. Streptomycin resistance was detected more frequently with LJ than BACTEC-MGIT-960 and ethambutol resistance was detected more frequently with BACTEC-MGIT-960 than LJ, but differences were not statistically significant. MDR-TB was detected in 27 cases by LJ and 25 by BACTEC-MGIT-960 and using both methods detected 29 cases.ConclusionsThere was a substantial degree of agreement between the two methods. However using the two in tandem increased the number of culture-positive patients and those with MDR-TB. The choice of culture method should depend on local availability, cost and test performance characteristics.

Clinical predictive value of in vitro anticancer drug sensitivity test for the therapeutic effect of adjuvant chemotherapy in patients with stage II–III colorectal cancer

Clinically useful predictors of the efficacy of adjuvant chemotherapy following curative colorectal surgery remain to be determined. In the present study, we investigated the clinical utility of the collagen gel droplet-embedded culture drug sensitivity test (CD-DST) as a predictor of the therapeutic response to 5-fluorouracil (5-FU)-based adjuvant chemo-therapy in patients with stage II–III colorectal cancer. CD-DST was conducted using tumor samples surgically obtained from 189 patients. The therapeutic effect of 5-FU-based regimens between high (high-group) and low (low-group) sensitivity groups and a group that did not receive chemotherapy [CTx(-) group] was compared. CD-DST was successfully performed in 151 out of the 189 patients (79.9%), 87 of whom received 5-FU-based adjuvant chemotherapy after surgery. Twenty-seven of these 87 patients (31.0%) were classified as the high-group and the remaining 60 (69.0%) as the low-group. The 5-year recurrence-free survival (RFS) in the high-group was significantly higher compared to that in the low- and the CTx(-) groups. No differences in the 5-year RFS were observed between the low- and CTx(-) groups. In conclusion, CD-DST appears to be useful for predicting the therapeutic response to 5-FU-based adjuvant chemotherapy in patients with stage II-III colorectal cancer.

A rare case of primary choriocarcinoma in the sigmoid colon

Primary colorectal choriocarcinoma is an extremely rare neoplasm and is usually associated with a poor prognosis. Only 13 cases of colorectal choriocarcinoma have previously been reported. There is no standard chemotherapeutic regimen for this tumor type. A 68-year-old man presented with melena and was diagnosed with sigmoid colonic adenocarcinoma with multiple liver metastases. He underwent a laparoscopic sigmoidectomy. Pathology revealed choriocarcinoma with a focal component of moderately differentiated adenocarcinoma of colon origin. Based on the collagen gel droplet-embedded culture drug sensitivity test (CD-DST) results, mFOLFOX6 and bevacizumab were administered, which suppressed aggressive tumor growth for 4 mo. The patient died 9 mo after the initial diagnosis. Our study results suggest that the standard chemotherapy regimen for colorectal cancer might have suppressive effects against primary colorectal choriocarcinoma. Moreover, CD-DST may provide, at least in part, therapeutic insight for the selection of appropriate antitumor agents for such patients.

Collagen gel droplet-embedded culture-drug sensitivity test and Ki67 expression in estrogen receptor-positive and HER2-negative breast cancer

Anthracyclines and taxanes are standard anticancer drugs used in breast cancer chemotherapy. In general, the efficacy of chemotherapy is lower in patients with estrogen receptor (ER)-positive tumors compared to patients with ER-negative tumors. Although less chemosensitive, ER-positive disease includes a subset of patients who significantly benefit from adjuvant chemotherapy. The collagen gel droplet-embedded culture-drug sensitivity test (CD-DST) is an in vitro chemosensitivity test that has several advantages over conventional tests. The aim of the present study was to examine the correlation between CD-DST and the expression of Ki67, an indicator of tumor proliferation, to evaluate the efficacy of anthracyclines and taxanes in patients with ER-positive and human epidermal growth factor receptor 2 (HER2)-negative breast cancer. CD-DST was performed in 68 patients with ER-positive and HER2-negative breast cancer between August 2001 and November 2006. The specimens obtained during surgery were used for the CD-DST and immunohistological examination of Ki67 expression. Chemosensitivity to the anticancer drugs adriamycin (ADM), epirubicin (EPI), docetaxel (DOC) and paclitaxel (PTX) was estimated using CD-DST. Results obtained from the CD-DST showed the chemosensitivity to each anticancer drug to be ADM, 23.7%; EPI, 75.0%; DOC, 69.2% and PTX, 43.6%. Ki67 expression was significantly higher in the group that was sensitive to DOC compared to the group that was resistant to DOC (P=0.048) and PTX (P=0.036). In addition, a significant correlation was observed between a Ki67 labeling index (LI) of >30% and chemosensitivity to PTX. In conclusion, results obtained from CD-DST and Ki67 expression levels are able to identify a subset of patients with ER-positive and HER2-negative breast cancer who exhibit sensitivity to chemotherapy, particularly to taxane therapy.

Association of epigenetic inactivation of the WRN gene with anticancer drug sensitivity in cervical cancer cells

The Werner (WRN) gene codes for a DNA helicase that contributes to genomic stability and has been identified as the gene responsible for progeria. Recent studies have shown reduced WRN expression due to aberrant DNA hypermethylation in cancer cells. Furthermore, WRN expression is thought to affect sensitivity to DNA topoisomerase I inhibitors in cancer therapy. In this study, we examined the relationship between aberrant DNA hypermethylation of WRN and the sensitivity of cervical cancer cells to anticancer drugs. DNA was extracted from samples from 22 patients with primary cervical cancer and 6 human cervical cancer-derived cell lines. Aberrant DNA hypermethylation was analyzed by methylation-specific PCR. WRN expression in cultured cells before and after addition of 5-aza-2-deoxycytidine, a demethylating agent, was examined using RT-PCR. The sensitivity of cells to anticancer drugs was determined using a collagen gel droplet embedded culture drug sensitivity test (CD-DST). siRNA against WRN was transfected into a cervical cancer-derived cell line with high WRN expression. Changes in drug sensitivity after silencing WRN were determined by CD-DST. Aberrant DNA hypermethylation and decreased expression of WRN were detected in 7/21 cases of primary cervical cancer and in two cervical cancer-derived cell lines. These two cell lines showed high sensitivity to CPT-11, a topoisomerase I inhibitor, but became resistant to CPT-11 after treatment with 5-aza-2-deoxycytidine. Transfection of siRNA against WRN increased the sensitivity of the cells to CPT-11. Aberrant DNA hypermethylation of WRN also increased the sensitivity of cervical cancer cells to CPT-11. Therefore, epigenetic inactivation of this gene may be a biomarker for selection of drugs for the treatment of cervical cancer. This is the first report to show a relationship between the methylation of the WRN gene and sensitivity to CPT-11 in gynecological cancers.

Abstract 1355: Utility of primary cultured cells in personalized chemotherapy for angiosarcoma of the oral cavity

Abstract Current treatments for major malignant tumors are based on evidences accumulated over the world and clinical trials with molecular target drugs that are expected to improve their prognosis are ongoing. In contrast, rare malignant tumors have no standard therapies and few evidences for effective drugs. Moreover, epidemiology, etiology, pathogenesis and molecular mechanisms are unknown because published data are based on a few case series and experimental materials can be used in vitro do not exist. Thus we have to manage a treatment case by case when facing a rare tumor. One of the useful methods to evaluate drug efficacy is the collagen gel droplet embedded culture drug sensitivity test (CD-DST), but a resected tumor tissue as an examination materials is limited. Primary cultured cells are thought to be an alternative material for various analyses. Angiosarcoma is a rare soft-tissue sarcoma of endothelial cell origin showing a poor prognosis. A 72-year-old man who has large masses on upper and lower gingiva came to our department and a palliative excision was performed. He also had multiple nodules in both lungs and cervical lymph nodes. Histopathological diagnosis was angiosarcoma because the immunohistochemical stainings showed that vimentin, CD31 and vW factor were positive. We attempted to culture the excised tumor specimen in vitro and obtained primary cultured cells with stable proliferation, and confirmed their in vivo tumorigenicity in athymic nude mice. First, both primary tumor tissues and cultured cells were assessed their sensitivity against 8 anti-tumor drugs by CD-DST. We evaluated their growth inhibitory effects as the ratio of total volume of colonies in the treated group to that in the untreated group (T/C%). The most effective drug, gemcitabine, had 20.9 T/C% in tumor tissues and 35.4 T/C% in cultured cells, and the second, docetaxel, had 32.2 T/C% and 40.2 T/C%, respectively. The other drugs showed the similar sensitivity between both types of samples. Next, we determined the gene expression profiles of both samples and a normal gingival tissue by microarray analysis. The data showed that 2,498 genes in primary tumor tissues and 2,893 genes in primary cultured cells had more than 5-fold change compared to control. Of these, 1,627 genes were common, and then we found the overexpression of 170 cancer-related genes including Aurora kinase A (AURKA) among these genes. Finally, we investigated the effect of a selective AURKA inhibitor MLN8237 on the growth of primary cultured angiosarcoma cells in vitro, and then observed the growth inhibitory effect of MLN8237 against these cells. These results suggest that primary cultured tumor cells may be useful for predicting the efficacies of various anti-tumor drugs and developing novel therapeutic strategies. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1355. doi:1538-7445.AM2012-1355

Complete Response of a Patient with Advanced Primary Splenic Histiocytic Sarcoma by Treatment with Chemotherapeutic Drugs Selected Using the Collagen Gel Droplet-embedded Culture Drug Sensitivity Test

A 69-year-old man presented with multiple nodules on the spleen and liver that had been detected by computed tomography (CT). A liver tumor biopsy was performed, and the patient was diagnosed to have histiocytic sarcoma (HS). Splenectomy was performed, and the chemosensitivity of the spleen tumor was measured using the collagen gel droplet-embedded culture drug sensitivity test (CD-DST). Hepatic arterial infusion chemotherapy was administered, based on the results of the CD-DST. The patient achieved complete remission (CR) after this therapy and remained alive without recurrence at the final follow-up. This is the first known case of CR in response to chemotherapy for advanced splenic HS.

Success Rate of Collagen Gel Droplet-embedded Culture Drug Sensitivity Test in Colorectal Cancer: Are Antibiotics a Prerequisite for Specimen Irrigation?

The collagen gel droplet-embedded culture drug sensitivity test (CD-DST) is one of the best chemosensitivity tests owing to its high success rate. However, CD-DST is often a culture method, and contamination is a serious problem, especially in the case of colorectal cancer, which is contaminated by enteric bacteria. It has been reported that the success rate of CD-DST is 64.0% in the case of colorectal cancer. Therefore, the sampling and washing of specimens before culture are extremely important. By washing specimens carefully with normal saline containing antibiotics, we achieved a success rate of 85.3% in the case of colorectal cancer. To improve the success rate, we started specimen irrigation with a large amount of normal saline in January 2007. As a result, a success rate exceeding 90% was acquired. For the success of CD-DST for colorectal cancer, it is important to irrigate specimens many times with a large amount of normal saline.

Intrathoracic chemo-thermotherapy with radiofrequency waves after extrapleural pneumonectomy for malignant pleural mesothelioma

Although multimodal treatment is advocated for malignant pleural mesothelioma (MPM), a standard therapeutic regimen has not been established. This study evaluated the outcome of our aggressive treatment including extrapleural pneumonectomy (EPP) and postoperative intrathoracic chemo-thermotherapy (PICT). Moreover, we assessed the association between the clinical effect and an in vitro chemosensitivity test. Eleven patients with MPM underwent treatment including EPP followed by PICT using 8 MHz radiofrequency waves. In vitro chemosensitivity was examined using the collagen gel droplet embedded culture drug-sensitivity test (CD-DST). Complete resection was performed in nine patients. More than two courses of PICT with sufficient heating were completely performed in seven patients. There was no perioperative mortality. Grade 3 or 4 toxicity was not recognized. The median overall survival was 19 months, and the median local relapse-free survival was 17 months. Local recurrence was recognized in four patients (36.4%). Of these patients, three had received incomplete PICT. Four patients with complete PICT including a CD-DST-sensitive chemoagent did not develop local recurrence. Of three patients who received complete PICT including a CD-DST-resistant chemoagent, one tumor recurred locally. The present multimodal treatment including EPP and PICT is promising in local control for MPM. Furthermore, CD-DST may provide clinically useful information for MPM.

Identification of responders/non-responders to 5-fluorouracil based on individual 50% inhibitory area under the concentration curve of 5-fluorouracil obtained with collagen gel droplet-embedded culture-drug sensitivity test in colorectal cancer

We previously reported the 5-fluorouracil (5-FU) sensitivity of cancer cells obtained from colorectal cancer (CRC) patients using the collagen gel droplet-embedded culture-drug sensitivity test (CD-DST). Multiple drug concentrations and contact durations, and the area under the concentration curve (AUC) and growth inhibition rate (IR) were combined, resulting in the AUC-IR curve, which was approximated to the logarithmic curve. Moreover, the individualized AUC(IR50), the AUC value which gives 50% growth inhibition, was calculated using the AUC-IR curve. This study aimed to identify responders/non-responders to 5-FU based on the individual AUC(IR50) obtained with CD-DST in order to establish individualized chemotherapy for CRC patients. The individual AUC(IR50) was calculated from each AUC-inhibition rate regression curve in all patients using the CD-DST. The cumulative distribution of the individual AUC(IR50) in CRC patients was evaluated. The cumulative distribution of the individual AUC(IR50) was regressed over the sigmoid curve (logarithmic scale). The approximate expression was almost exactly y=ab^exp(-cx) (a=0.9739, b=1.7096E-21, c=0.8990, the sum of square residuals, 0.0279). In the 80 cases examined, no notable change was observed in the regression curve when the number of patients increased. A standard curve was obtained describing responders to 5-FU among all CRC patients. From this standard curve, we ascertained that non-responders accounted for approximately 5% of all patients. Moreover, we were able to classify responders into good or intermediate responders to 5-FU. The standard curve describing response to 5-FU in CRC patients offers a useful tool in the establishment of individualized chemotherapy.

Chemosensitivity test for 5-fluorouracil and 5-chloro-2, 4-dihydroxypyridine predicts outcome of gastric cancer patients receiving S-1 postoperatively

Chemosensitivity tests have long been discussed but remain a topic of research. In this study, we investigated the correlation between the results of a chemosensitivity test for 5-fluorouracil and 5-chloro-2, 4-dihydroxypyridine and the clinical outcomes of gastric cancer patients treated with S-1, an oral fluoropyrimidine, as adjuvant chemotherapy. For gastric cancer patients, we performed surgical treatment and a lymph node dissection of D2 or more. Afterwards, a chemosensitivity test for 5-fluorouracil and 5-chloro-2, 4-dihydroxypyridine was performed, using the collagen gel droplet embedded culture drug-sensitivity test (CD-DST), in surgical specimens. All the patients received postoperative adjuvant chemotherapy with S-1 for 1 year, and the overall survival (OS), relapse-free survival (RFS), and adverse events were investigated. The chemosensitivity test was performed for 27 patients. The growth inhibition rate (IR) was 50% or more (high-sensitivity group) in 59.3% (16 cases) and it was under 50% (low-sensitivity group) in 40.7% (11 cases). The 3-year OS rate was 100% in the high-sensitivity group and 62.34% in the low-sensitivity group. The 3-year RFS rate was 83.33% in the high-sensitivity group and 24.24% in the low-sensitivity group. Thus, the 3-year OS rate and the 3-year RFS rate were higher in the high-sensitivity group than in the low-sensitivity group. No adverse events of grade 3 or greater severity were observed. The results of the chemosensitivity test were correlated with the patient outcome. Therefore, such results might be useful for individualizing cancer chemotherapy and for determining future indications for postoperative adjuvant chemotherapy.

Synovial sarcoma individual chemotherapy directed by collagen gel droplet embedded culture drug sensitivity test: A case report

The collagen gel droplet embedded culture-drug sensitivity test (CD-DST) is an anticancer drug sensitivity test developed about 10 years ago. This study reports the application of this test in the choice of neoadjuvant chemotherapy for the treatment of one patient with a large synovial sarcoma in the right shank. A 28-year old man presented at our hospital with a large mass in his right shank which had a hard texture and an obscure boundary. The histopathological diagnosis of excisional biopsy specimens was synovial sarcoma with low differentiation. Theprubicin/Cisplatin (THP/CDDP) neoadjuvant chemotherapy was selected based on the results obtained from the CD-DST. After three courses, a computed tomography (CT) scan was performed which indicated that the volume of the tumor had decreased significantly. Additionally, tumor necrosis, as well as the clinical response, showed complete response. The histopathological diagnosis of wide excision specimens indicated a grade III chemotherapy response. The patient was alive and without recurrence after a follow-up of 16 months. Our results indicated that the CD-DST is a useful tool for selecting neoadjuvant chemotherapeutic drugs for patients with synovial sarcoma.

Association of ATP7A expression and in vitro sensitivity to cisplatin in non-small cell lung cancer

Expression of copper-transporting P-type adenosine triphosphatase A (ATP7A) is reportedly associated with platinum drug resistance in various types of solid tumors. However, the impact of ATP7A expression on platinum drug resistance in non-small cell lung cancer (NSCLC) has yet to be adequately elucidated. In vitro cisplatin (CDDP) sensitivity was investigated using the collagen gel-droplet embedded culture drug sensitivity test, and the ATP7A mRNA expression levels were assessed by real-time polymerase chain reaction in surgically resected specimens of NSCLC. The relationship between the ATP7A expression levels and the in vitro CDDP sensitivity was then evaluated. The ATP7A mRNA expression levels in the CDDP-resistant tumors were significantly higher than those in the CDDP-sensitive tumors (p=0.0167, Mann-Whitney U test). In conclusion, the results suggest that evaluation of ATP7A expression is useful as a marker for cisplatin chemoresistance.

Anticancer drug sensitivity testing using an oxygen electrode apparatus

Conventional anticancer drug sensitivity testing methods, such as succinate dehydrogenase inhibition (SDI), histoculture drug-response assay (HDRA) and collagen gel droplet embedded culture drug sensitivity testing (CD-DST), all require primary culturing and are extremely complex tests that require considerable time for analysis. A major drawback of these methods is that if culturing is not performed properly, ambiguous results are produced. Therefore, we developed an oxygen electrode apparatus that uses cellular metabolism as an indicator of anticancer drug sensitivity and investigated its usefulness in 29 breast cancer patients with the following histopathological classifications: papillotubular carcinoma (n= 15); solid tubular carcinoma (n= 6); and scirrhous carcinoma (n= 8). Comparison of anticancer drug sensitivity testing results obtained using the conventional HDRA method and those obtained using the oxygen electrode apparatus showed significant reproducibility between the two methods. In addition, similar anticancer drug sensitivity testing results using the oxygen electrode apparatus were obtained for in vivo testing of nude mice transplanted with established cancer cell lines. These findings suggest that the oxygen electrode apparatus is a useful procedure in anticancer drug sensitivity testing that provides better reproducibility and that is faster, more convenient, and less expensive than other testing methods.

Genome-wide cDNA microarray screening to reveal gene-expression profiles correlated to chemosensitivity of oral squamous cell carcinoma cell lines

One of the most critical issues of cancer chemotherapy is to establish a method for predicting efficacy or toxicity of anti-cancer drugs for individual patients. To identify genes that correlate with chemosensitivity of oral cancer treatment, we performed cDNA microarray analysis of nine oral squamous cell carcinoma (OSCC) cell lines. We compared gene-expression profiling with the sensitivity of OSCC cell lines to five anti-cancer drugs (5-fluorouracil, cisplatin, docetaxel, mitomycin C and adriamycin), which were measured using the collagen gel droplet embedded culture-drug sensitivity test method. We found significant associations between dozens of gene-expression levels and chemosensitivity of OSCC cell lines. These data should prove useful in the identification of predictive drug sensitivity markers, which may eventually provide “personalized chemotherapy” for individual patients, as well as for the development of novel drugs against chemotherapeutic resistance.