epothilone-a and Liver-Neoplasms

Breast cancer consists of a heterogeneous group of diseases, with a number of tumor-specific and patient-specific factors, which influence response to therapy and survival. Ixabepilone is a member of a novel class of antineoplastic agents, the epothilones, that has demonstrated activity in a number of human solid tumor types and is the first agent in this class to be approved by the Food and Drug Administration (FDA) for the treatment of metastatic or locally advanced breast cancer, that is resistant/refractory to anthracyclines, taxanes, and/or capecitabine. Both retrospective and prospective studies have been conducted to evaluate the efficacy of ixabepilone in various populations. The role of ixabepilone in poor prognosis subgroups of the metastatic breast cancer population is reviewed in this article.

Topics: Adult; Aged; Brain Neoplasms; Breast Neoplasms; Bridged-Ring Compounds; Clinical Trials, Phase III as Topic; Drug Approval; Drug Delivery Systems; Drug Resistance, Neoplasm; Epothilones; Female; Humans; Liver Neoplasms; Lung Neoplasms; Lymphatic Metastasis; Middle Aged; Neoplasm Invasiveness; Neoplasm Staging; Patient Selection; Prognosis; Randomized Controlled Trials as Topic; Survival Analysis; Taxoids; Treatment Outcome; United States; United States Food and Drug Administration

Patients with metastatic breast cancer (MBC) have poor prognoses and 5-year survival rates of approximately 20%. The site(s) and degree of metastatic dissemination are among the principal prognostic factors for patients with MBC. Patients with visceral metastases to the liver and/or lung have a very poor prognosis. Although good performance status, restricted disease dissemination, and limited extent of metastatic infiltration are associated with higher responses to chemotherapy, responses are generally short lived, with rapid disease progression after treatment failure. Thus, novel strategies for the management of patients with MBC with visceral disease are urgently needed. We have analyzed outcomes of trials that evaluated various chemotherapeutic agents as monotherapy or in combination with capecitabine in patients with MBC with primary visceral disease involvement. Treatment with microtubule inhibitors such as paclitaxel, docetaxel, and albumin-bound paclitaxel, generally administered in earlier lines of treatment, resulted in comparable responses. Lower response rates (RRs) were reported with other agents such as capecitabine, vinorelbine, and gemcitabine. Adverse events consistent with known toxicities of each agent were observed in the selected trials and related to dose and administration schedule. The epothilone B analogue ixabepilone has demonstrated clinical efficacy and manageable safety in populations of heavily pretreated patients with MBC with high visceral disease burdens to liver and/or lung (61%-86% of patients). Objective RRs ranging from 12% to 57% have been reported for ixabepilone, as monotherapy and in combination with capecitabine, depending on degree of pretreatment. Responses to ixabepilone in patients with visceral metastases were comparable to those observed in overall study patient populations.

Topics: Antineoplastic Agents; Breast Neoplasms; Clinical Trials as Topic; Epothilones; Female; Humans; Liver Neoplasms; Lung Neoplasms; Neoplasm Metastasis; Viscera

Health-related quality of life (HRQoL) enhances understanding of treatment effects that impact clinical decision-making. Although the primary end-point was not achieved, the BEACON (BrEAst Cancer Outcomes with NKTR-102) trial established etirinotecan pegol, a long-acting topoisomerase-1 (TOP1) inhibitor, as a promising therapeutic for patients with advanced/metastatic breast cancer (MBC) achieving clinically meaningful benefits in median overall survival (OS) for patients with stable brain metastases, with liver metastases or ≥ 2 sites of metastatic disease compared to treatment of physician's choice (TPC). Reported herein are the findings from the preplanned secondary end-point of HRQoL.. HRQoL, assessed by European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire-Core 30 (QLQ-C30) (version 3.0) supplemented by the breast cancer-specific Quality of Life Questionnaire (QLQ-BR23), was evaluated post randomisation in 733 of 852 patients with either anthracycline-, taxane- and capecitabine-pretreated locally recurrent or MBC randomised to etirinotecan pegol (n = 378; 145 mg/m. Differences were seen favouring etirinotecan pegol up to 32 weeks for global health status (GHS) and physical functioning scales (P < 0.02); numerical improvement was reported in other functional scales. The findings from HRQoL symptom scales were consistent with adverse event profiles; etirinotecan pegol was associated with worsening gastrointestinal symptoms whereas TPC was associated with worsened dyspnoea and other systemic side-effects. Analysis of GHS and physical functioning at disease progression showed a decline in HRQoL in both treatment arms, with a mean change from baseline of -9.4 and -10.8 points, respectively.. There was evidence of benefit associated with etirinotecan pegol compared with current standard of care agents in multiple HRQoL measurements, including global health status and physical functioning, despite worse gastrointestinal symptoms (e.g. diarrhoea). Patients in both arms had a decline in HRQoL at disease progression.. NCT01492101.

Topics: Activities of Daily Living; Adult; Aged; Aged, 80 and over; Albumins; Anorexia; Antineoplastic Agents; Body Image; Bone Neoplasms; Brain Neoplasms; Breast Neoplasms; Cancer Pain; Deoxycytidine; Docetaxel; Dyspnea; Epothilones; Fatigue; Female; Furans; Gemcitabine; Health Status; Heterocyclic Compounds, 4 or More Rings; Humans; Ketones; Liver Neoplasms; Lung Neoplasms; Middle Aged; Nausea; Paclitaxel; Polyethylene Glycols; Quality of Life; Reproductive Health; Sleep Initiation and Maintenance Disorders; Taxoids; Vinblastine; Vinorelbine; Vomiting

Only a limited number of cytotoxic drugs have shown activity in metastatic colorectal carcinoma. Patupilone is a novel agent with promising activity in this common cancer. Diarrhea represents the dose-limiting toxicity of patupilone. Measurement of intestinal permeability is one of the potential methods of non-invasive laboratory assessment of gastrointestinal toxicity.. We have assessed intestinal permeability by measuring absorption of lactulose, mannitol and xylose in 27 previously treated patients with metastatic colorectal cancer enrolled in a phase I trial of patupilone.. Lactulose/mannitol and lactulose/xylose ratios increased after the treatment. Significantly higher lactulose/mannitol ratio was observed in patients who had severe diarrhea. Moreover, patients who subsequently had an adverse event of grade 3 or higher had significantly higher baseline lactulose/mannitol or lactulose/xylose ratios.. Measurement of intestinal permeability using the lactulose/mannitol test may represent a biomarker for the monitoring, or even prediction of toxicity of cytotoxic drugs, including patupilone.

Topics: Aged; Antineoplastic Agents; Colonic Neoplasms; Diarrhea; Epothilones; Female; Humans; Intestinal Mucosa; Intestines; Lactulose; Liver Neoplasms; Male; Mannitol; Middle Aged; Permeability; Xylose

Hepatobiliary cancers respond poorly to cytotoxic chemotherapy. We evaluated the activity and safety of ixabepilone, an epothilone B analogue which stabilizes microtubules, in a phase II trial in patients with advanced cancers of the gallbladder, bile duct, and liver.. Eligible patients had previously-untreated, histologically-proven unresectable hepatobiliary cancer. Ixabepilone, 40 mg/m(2), was administered intravenously over 3 h every 21 days.. Between January 2002 and April 2005, 54 patients (19 hepatocelluar carcinoma, 13 cholangiocarcinomas, 22 gallbladder carcinomas) were enrolled; 47 patients were evaluable for efficacy. The objective response rate was 8.5%; 51% had stable disease. Median overall survival was 7.0 months (95% CI, 5.0 to 10.8 months) and median progression-free survival was 2.6 months (95% CI, 1.4 to 4.1 months). Grade 3/4 toxicities included neutropenia (39%), fatigue (9%), allergic/hypersensitivity reaction (4%) and sensory neuropathy (4%).. Single agent ixabepilone has limited activity in advanced hepatobiliary cancers.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Agents; Biliary Tract Neoplasms; Epothilones; Female; Humans; Kaplan-Meier Estimate; Liver Neoplasms; Male; Middle Aged; Neoplasm Staging; Treatment Outcome; Universities; Young Adult

The objectives of this phase I trial were to determine the maximum-tolerated dose (MTD), toxicity profile, dose-limiting toxicities (DLTs), pharmacokinetics, and preliminary response rate for ixabepilone, a microtubule-stabilizing agent, administered intravenously daily for 5 days in children and adolescents.. Patients >or= 2 and 5 days and grade 3 fatigue) were observed in two of three patients receiving 10 mg/m(2)/d. The MTD of ixabepilone administered daily for 5 days every 21 days was 8 mg/m(2)/d. Myelosuppression, GI, and hepatic toxicities were common non-DLTs. Peripheral neuropathy was uncommon. Ixabepilone clearance was 475 +/- 247 mL/min/m(2), volume of distribution at steady-state was 12.2 +/- 5.4 L/kg, and half-life was 14 hours.. The recommended dose of ixabepilone for phase II trials in solid tumors is 8 mg/m(2)/d daily for 5 days every 21 days. This dose is 33% higher than the MTD in adults receiving the same dosing schedule. Pharmacokinetic parameters in children and adolescents were highly variable but similar to adults.

Topics: Adolescent; Child; Child, Preschool; Epothilones; Female; Hepatoblastoma; Humans; Kidney Neoplasms; Liver Neoplasms; Male; Maximum Allowable Concentration; Neuroblastoma; Sarcoma; Wilms Tumor

Oestrogen receptor (ER)-negative breast cancer, including oestrogen receptor-, progesterone receptor- and human epidermal growth factor receptor 2-negative (ER/PR/HER2-negative) breast cancer, is more aggressive than ER-positive disease. A major limitation in the treatment of ER-negative disease subtypes is the inherent insensitivity to hormonal agents (tamoxifen, aromatase inhibitors) that are widely used in the treatment of breast cancer. Thus, therapeutic options for poor prognosis patients with ER-negative breast cancer are limited to a handful of chemotherapeutic agents, and new agents are needed to improve the treatment of this disease. Ixabepilone, a novel epothilone B analogue with low susceptibility to cellular mechanisms that confer resistance to taxanes and other chemotherapeutic agents, has demonstrated potent preclinical antitumour activity in multiple models, including those with primary or acquired drug resistance. This review summarises the results of a prospective subset analysis from a phase III clinical trial evaluating ixabepilone for the treatment of metastatic breast cancer (MBC), in which efficacy and safety were evaluated in patients with ER-negative and ER/PR/HER2-negative disease.

Topics: Antimetabolites, Antineoplastic; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Biomarkers, Tumor; Breast Neoplasms; Capecitabine; Deoxycytidine; Drug Resistance, Neoplasm; Epidemiologic Methods; Epothilones; ErbB Receptors; Female; Fluorouracil; Humans; Liver Neoplasms; Lung Neoplasms; Receptors, Estrogen; Receptors, Progesterone; Treatment Outcome

To determine if ixabepilone is a substrate for cytochrome P450 3A4 (CYP3A4) and if its metabolism by this cytochrome is clinically important, we did a clinical drug interaction study in humans using ketoconazole as an inhibitor of CYP3A4.. Human microsomes were used to determine the cytochrome P450 enzyme(s) involved in the metabolism of ixabepilone. Computational docking (CYP3A4) studies were done for epothilone B and ixabepilone. A follow-up clinical study was done in patients with cancer to determine if 400 mg/d ketoconazole (inhibitor of CYP3A4) altered the pharmacokinetics, drug-target interactions, and pharmacodynamics of ixabepilone.. Molecular modeling and human microsomal studies predicted ixabepilone to be a good substrate for CYP3A4. In patients, ketoconazole coadministration resulted in a maximum ixabepilone dose administration to 25 mg/m(2) when compared with single-agent therapy of 40 mg/m(2). Coadministration of ketoconazole with ixabepilone resulted in a 79% increase in AUC(0-infinity). The relationship of microtubule bundle formation in peripheral blood mononuclear cells to plasma ixabepilone concentration was well described by the Hill equation. Microtubule bundle formation in peripheral blood mononuclear cells correlated with neutropenia.. Ixabepilone is a good CYP3A4 substrate in vitro; however, in humans, it is likely to be cleared by multiple mechanisms. Furthermore, our results provide evidence that there is a direct relationship between ixabepilone pharmacokinetics, neutrophil counts, and microtubule bundle formation in PBMCs. Strong inhibitors of CYP3A4 should be used cautiously in the context of ixabepilone dosing.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Agents; Computational Biology; Cytochrome P-450 CYP3A; Cytochrome P-450 CYP3A Inhibitors; Epothilones; Female; Genital Neoplasms, Female; Humans; Ketoconazole; Leukocytes, Mononuclear; Liver; Liver Neoplasms; Male; Microsomes, Liver; Middle Aged; Neoplasms; Prostatic Neoplasms; Tubulin Modulators

Liver carcinoma generally presents as an immunosuppressive microenvironment that promotes tumor evasion. The intercellular crosstalk of immune cells significantly influences the construction of an immunosuppressive microenvironment. This study aimed to investigate the important interactions between immune cells and their targeting drugs in liver carcinoma, by using single-cell and bulk transcriptomic data.. Single-cell and bulk transcriptomic data were retrieved from Gene Expression Omnibus (GSE159977, GSE136103, and GSE125449) and The Cancer Genome Atlas (TGCA-LIHC), respectively. Quality control, dimension reduction, clustering, and annotation were performed according to the Scanpy workflow based on Python. Cell-cell interactions were explored using the CellPhone database and CellChat. Trajectory analysis was executed using a partition-based graph abstraction method. The transcriptomic factors (TFs) were predicted using single-cell regulatory network inference and clustering (SCENIC). The target genes from TFs were used to establish a related score based on the TCGA cohort; this score was subsequently validated by survival, gene set enrichment, and immune cell infiltration analyses. Drug prediction was performed based on the Cancer Therapeutics Response Portal and PRISM Repurposing datasets.. Thirty-one patients at four different states, including health, hepatitis, cirrhosis, and cancer, were enrolled in this study. After dimension reduction and clustering, twenty-two clusters were identified. Cell-cell interaction analyses indicated that macrophage-naive CD4 + T cell interaction significantly affect cancerous state. In brief, macrophages interact with naive CD4 + T cells via different pathways in different states. The results of SCENIC indicated that macrophages present in cancer cells were similar to those present during cirrhosis. A macrophage-naive CD4 + T cell (MNT) score was generated by the SCENIC-derived target genes. Based on the MNT score, five relevant drugs (inhibitor of polo-like kinase 1, inhibitor of kinesin family member 11, dabrafenib, ispinesib, and epothilone-b) were predicted.. This study reveals the crucial role of macrophage-naive CD4 + T cell interaction in the immunosuppressive microenvironment of liver carcinoma. Tumor-associated macrophages may be derived from cirrhosis and can initiate liver carcinoma. Predictive drugs that target the macrophage-naive CD4 + T cell interaction may help to improve the immunosuppressive microenvironment and prevent immune evasion. The relevant mechanisms need to be further validated in experiments and cohort studies.

Topics: Biomarkers, Tumor; Carcinoma, Hepatocellular; Cell Communication; Epothilones; Humans; Kinesins; Liver Cirrhosis; Liver Neoplasms; Macrophages; T-Lymphocytes; Transcriptome; Tumor Microenvironment

High mortality rates in ovarian and liver cancer are largely a result of resistance to currently used chemotherapy. Here, we investigated genotoxic and pro-oxidant effects of metformin (MET) and epothilone A (A) in combination with respect to apoptosis in HepG2 and SKOV-3 cancer cells. Reactive oxygen species (ROS) was studied using 2',7'-dichlorodihydrofluoresein diacetate, and samples were analyzed for the presence and absence of the N-acetylcysteine (NAC). Expression of genes involved in programmed cell death, oxidative and alkylating DNA damage was measured. Probes were analyzed in the presence of Akt or nuclear factor-κB inhibitor. Compared to either drug alone, combination of epothilone A and metformin was more potent; decreased Akt level; and elevated percentage of apoptotic cells, induced cell cycle arrest at G1 phase and elevated the sub-G1 cell population by increasing the mRNA level of caspase-3, poly (ADP-ribose) polymerase-1 and H2AX. The anticancer effect of the drug combination was partially reversed by NAC supplementation, suggesting that ROS generation is required to induce apoptosis. The present study demonstrates that novel combination such as epothilone A and MET show promise in expanding ovarian and liver cancer therapy.

Topics: Adenocarcinoma; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Carcinoma, Hepatocellular; Caspase 3; Cell Line, Tumor; DNA Damage; Drug Resistance, Neoplasm; Epothilones; Female; Gene Expression Regulation, Neoplastic; Histones; Humans; Hypoglycemic Agents; Liver Neoplasms; Metformin; Neoplasm Proteins; Ovarian Neoplasms; Oxidative Stress; Poly (ADP-Ribose) Polymerase-1; Proto-Oncogene Proteins c-akt

Type 2 diabetes mellitus patients are at increased risk of many forms of malignancies, especially of the pancreas, colon and hepatocellular cancer. Unfortunately, little is known of the possible interaction between antidiabetic drugs and anticancer agents. The present study investigates the influence of metformin (MET) and sitagliptin (SITA) on the in vitro anticancer activity of the microtubule depolymerization inhibitor agent epothilone A (EpoA). Hepatocellular liver carcinoma cell line (HepG2) viability and apoptosis were determined by the MTT test and by double staining with PO-PRO-1 and 7-aminoactinomycin D, respectively, after treatment with EpoA, metformin or sitagliptin. The levels of nuclear factor NF-κB and p53 were evaluated in the presence and absence of inhibitors. While EpoA and MET inhibited HepG2 cell proliferation, SITA did not. EpoA and SITA induced higher p53 levels than MET. All tested drugs increased the level of NF-κB. Only MET enhanced the proapoptotic effect of EpoA. The EpoA+MET combination evoked the highest cytotoxic effect on HepG2 cells and led to apoptosis independent of p53, decreasing the level of NF-κB. These findings support the link between NF-κB and p53 in the modulation of apoptotic effects in HepG2 cells treated by EpoA. Our studies indicate that the combination of EpoA and MET applied in subtoxic doses has a stronger cytotoxic effect on liver cancer cells than each of the compounds alone. The therapeutic advantages of the combination of EpoA with MET may be valuable in the treatment of patients with diabetes mellitus type 2 (T2DM) and liver cancer.

Topics: Antineoplastic Agents; Apoptosis; Benzoxazoles; Carcinoma, Hepatocellular; Dactinomycin; Diabetes Mellitus, Type 2; Drug Therapy, Combination; Epothilones; Hep G2 Cells; Humans; Hypoglycemic Agents; Liver Neoplasms; Metformin; NF-kappa B; Sitagliptin Phosphate; Tumor Suppressor Protein p53

Hepatocellular carcinoma (HCC) is one of the most common and challenging malignant disease. The prognosis is poor in patients with advanced disease. Although sorafenib prolongs survival in these patients, improvement remains modest. We used doxorubicin and sorafenib as controls and screened eight new agents including ixabepilone, gefitinib, cetuximab, brivanib, dasatinib, sunitinib, BMS-690514, and BMS-536924 against nine HCC cell lines and evaluated their interactions. We studied growth inhibition of 10 drugs against nine HCC cell lines. Single-agent activity was tested using an MTS assay. Combination studies were carried out in both resistant and sensitive cells to determine the combination index. The IC50 of each agent varied widely among nine cell lines. Ixabepilone was more potent than doxorubicin. HT-17 cells were more sensitive to gefitinib and cetuximab than the other eight cell lines. BMS-536924 showed good efficacy (IC50 ≤ 1 µmol/l) on all three α-fetoprotein (AFP)-producing cell lines (HepG2, Hep3B, Huh-7). Three cell lines showed moderate sensitivity to dasatinib (IC50 ≤ 1 µmol/l). Dasatinib showed the most frequent and strongest synergism with ixabepilone, gefitinib, brivanib, BMS-690514, or BMS-536924. Ixabepilone, sorafenib, brivanib, dasatinib, and BMS-536924 are active against HCC cell lines. The heterogeneity of the sensitivity of each cell line emphasizes the need for individualized treatment. The sensitivity to BMS-536924 is closely associated with the production of AFP. AFP may be a biomarker predicting response to the insulin-like growth factor-1 receptor inhibitor in HCC patients. Additional studies are warranted. The synergism between dasatinib and other agents also provides future research directions to understand drug resistance and improve outcome.

Topics: Alanine; alpha-Fetoproteins; Antibodies, Monoclonal, Humanized; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Benzimidazoles; Carcinoma, Hepatocellular; Cetuximab; Dasatinib; Doxorubicin; Drug Screening Assays, Antitumor; Epothilones; Gefitinib; Humans; Indoles; Inhibitory Concentration 50; Liver Neoplasms; Niacinamide; Phenylurea Compounds; Piperidines; Pyridones; Pyrimidines; Pyrroles; Quinazolines; Sorafenib; Sunitinib; Thiazoles; Triazines

High doses (10 nM) of epothilone B, a microtubule stabilizer, will inhibit the development of human tumor-derived angiogenesis following short (14 d) drug exposure times. Metronomic dosing regimes use lower drug doses and prolonged drug exposure times in an attempt to decrease toxicity compared with standard dosing schedules. We hypothesized that epothilone B would be an effective anti-angiogenic agent when administered at very low doses over an extended period of time.. Fragments of four fresh human tumors were cultured in a fibrin-thrombin matrix and maintained in nutrient media plus 20% fetal bovine serum (FBS) for 56 d. Tumor fragments (n=40-60 per group) were exposed to weekly doses of epothilone B at concentrations of 10, 5, 1, 0.5, or 0.1 nM. All of these concentrations are clinically achievable. Tumor angiogenesis was assessed weekly on d 14-56 using a validated visual grading system. This system rates neovessel growth, density, and length on a 0-16 scale [angiogenic index, (AI)]. The average change in AI between d 14 and 56 was calculated for all samples and used to evaluate the metronomic response.. Epothilone B produced a dose-dependent anti-angiogenic response in all tumors. Two of the four tumors demonstrated a clear and significant metronomic anti-angiogenic effect over time.. Epothilone B, when dosed by a metronomic schedule may have a significant anti-angiogenic effect on human solid tumors. This study provides evidence for the potential use of epothilone B on a metronomic dosing schedule.

Topics: Angiogenesis Inhibitors; Carcinoid Tumor; Cells, Cultured; Dose-Response Relationship, Drug; Epothilones; Gastrointestinal Stromal Tumors; Humans; Intestinal Neoplasms; Liver Neoplasms; Male; Neovascularization, Pathologic; Testicular Neoplasms

In this study, the cytotoxic effects of patupilone (epothilone B; EPO906) were assessed in a panel of hepatocellular carcinoma (HCC) cell lines, and were compared with doxorubicin and the microtubule-stabilizing taxanes.. The following HCC cell lines were used: PLC/PRF/5, HepG2, Hep3B, SNU-387, SNU-398, SNU-423, SNU-449, and SNU-475. Cells were treated with various concentrations of patupilone, paclitaxel, docetaxel, or doxorubicin for 72 h; 50% inhibitory concentrations (IC(50)) were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay. P-glycoprotein expression was assessed using standard Western blotting techniques.. Patupilone was found to be the most potent drug in all 8 HCC cell lines. All cell lines except SNU-449 were 4- to19-fold more sensitive to patupilone than to paclitaxel and docetaxel, and 59- to 208-fold more sensitive than to doxorubicin. SNU-449, the most resistant cell line and the only one overexpressing P-glycoprotein, was 3- to 39-fold more resistant to paclitaxel, docetaxel, and doxorubicin than were other cell lines. The IC(50) of patupilone in SNU-449 was 1.14 nmol, which was 108- to 529-fold lower than those of the other agents.. Patupilone was more potent than taxanes and doxorubicin in HCC cell lines and may result in reduced clinical resistance by overcoming P-glycoprotein overexpression. A clinical study in HCC is warranted.

Topics: Antineoplastic Agents; ATP Binding Cassette Transporter, Subfamily B, Member 1; Carcinoma, Hepatocellular; Cell Line, Tumor; Docetaxel; Doxorubicin; Drug Resistance, Neoplasm; Epothilones; Humans; Liver Neoplasms; Paclitaxel; Taxoids

Different Sorangium cellulosum strains not only showed diversity in their cell and fruiting body morphologies, but also differences of bio-activities and components of the metabolites. All the Sorangial strains studied in this paper had no activity on Gram-negative bacteria, some were able to repress Gram-positive bacteria. However, all the strains were able to repress growth of fungi and tumor cells strongly and widely. Thin layer chromatography assay of metabolites showed multi-components in the metabolites, and most of them have abilities of repressing fungi and tumor cells in different degrees. Four strains were found to be able to produce compounds with activity of promoting polymerization of microtubule. Based on Rf value on TLC, the bio-active component produced by So33-1 strain was similar to Epothilone A, while that of So81 was much different. The results of this paper suggested that Sorangium cellulosum is a much beneficial resource for screening nature compounds with bio-activities against eukaryotes.

Topics: Antineoplastic Agents; Carcinoma, Hepatocellular; Cell Line, Tumor; Epothilones; Humans; Liver Neoplasms; Microtubules; Myxococcales; Species Specificity