Ultrasonic absorption frequency dependence of two widely used anti-cancer drugs: doxorubicin and daunorubicin

Recursive Random Lasso (RRLasso) for Identifying Anti-Cancer Drug Targets

Uncovering driver genes is crucial for understanding heterogeneity in cancer. L1-type regularization approaches have been widely used for uncovering cancer driver genes based on genome-scale data. Although the existing methods have been widely applied in the field of bioinformatics, they possess several drawbacks: subset size limitations, erroneous estimation results, multicollinearity, and heavy time consumption. We introduce a novel statistical strategy, called a Recursive Random Lasso (RRLasso), for high dimensional genomic data analysis and investigation of driver genes. For time-effective analysis, we consider a recursive bootstrap procedure in line with the random lasso. Furthermore, we introduce a parametric statistical test for driver gene selection based on bootstrap regression modeling results. The proposed RRLasso is not only rapid but performs well for high dimensional genomic data analysis. Monte Carlo simulations and analysis of the "Sanger Genomics of Drug Sensitivity in Cancer dataset from the Cancer Genome Project" show that the proposed RRLasso is an effective tool for high dimensional genomic data analysis. The proposed methods provide reliable and biologically relevant results for cancer driver gene selection.

Antitumor effect of TNP-470, an angiogenesis inhibitor, combined with ultrasound irradiation for human uterine sarcoma xenografts evaluated using contrast color Doppler ultrasound

Microvascular endothelial cells, which are recruited by tumors, have become an important target in cancer therapy. This study firstly examined the antitumor effect of angiogenesis inhibitor combined with ultrasound (US) irradiation for human cancer in vivo and evaluated its vascularity using color Doppler US in real time with a microbubble US contrast agent. A human uterine sarcoma cell line, FU-MMT-1, was used in vivo because this tumor is one of the most malignant neoplasms of the human solid tumors and it also has a poor response to any of the chemotherapeutic agents currently used, as well as to radiotherapy. In angiogenic inhibitors, TNP-470 was selected to use in an in vivo study, because this agent showed a higher inhibitory effect in tube formation assay in vitro, than that of FR118487, or thalidomide. The FU-MMT-1 xenografts in nude mice were treated using US at a low-intensity (2.0 w/cm(2), 1MHZ) for 4 min three times per week each after the subcutaneous injection of TNP-470 (30 mg/kg), an angiogenesis inhibitor, and this treatment was continued for 8 weeks. Either treatment of US alone or TNP-470 alone showed a suppression of tumor growth, in comparison to the non-treatment group (control), and a significantly enhanced effect was obtained using the combined treatment. A reduction in the intratumoral vascularity, which was evaluated using both color Doppler and immunohistochemistry, was significantly demonstrated using the combined treatment, in comparison to each treatment alone, and the control. No side-effect was observed in any mice in the combined treatment group. These results suggest that the antitumor effect of TNP-470 for uterine sarcoma was accelerated by US irradiation in vivo and this combination might be a potentially effective for new cancer therapy.

Statistical-mechanical theory of ultrasonic absorption in molecular liquids

We present results of the theoretical description of ultrasonic phenomena in molecular liquids. In particular, we are interested in the development of a microscopical, i.e., statistical-mechanical, framework capable of explaining the long living puzzle of excess ultrasonic absorption in liquids. Typically, an ultrasonic wave in a liquid can be generated by applying a periodically alternating external pressure with an angular frequency that corresponds to the ultrasound. If the perturbation introduced by such a process is weak, its statistical-mechanical treatment can be done with the use of a linear response theory. We treat the liquid as a system of interacting sites, so that all the response/aftereffect functions as well as the energy dissipation and generalized (wave-vector and frequency-dependent) ultrasonic absorption coefficient are obtained in terms of familiar site-site static and time correlation functions such as static structure factors or intermediate scattering functions. To express the site-site intermediate scattering functions, we refer to the site-site memory equations in the mode-coupling approximation for first-order memory kernels, while equilibrium properties such as site-site static structure factors, and direct and total correlation functions are deduced from the integral equation theory of molecular liquids known as RISM, or one of its generalizations. All of the formalism is phrased in a general manner, hence the results obtained are expected to work for arbitrary types of molecular liquids including simple, ionic, polar, and nonpolar liquids.

DNA damage induced by micellar-delivered doxorubicin and ultrasound: comet assay study

To minimize adverse side effects of chemotherapy, we have developed a micellar drug carrier that retains hydrophobic drugs, and then releases the drug by ultrasonic stimulation. This study investigated the DNA damage induced by doxorubicin (DOX) delivered to human leukemia (HL-60) cells from pluronic P-105 micelles with and without the application of ultrasound. The comet assay was used to quantify the amount of DNA damage. No significant DNA damage was observed when the cells were treated with 0.1, 1 and 10 wt% P-105 with or without ultrasound (70 kHz, 1.3 W/cm(2)) for 1 h or for up to 3 h in 10 wt% P-105. However, when cells were incubated with 10 microg/ml free DOX for up to 9 h, DNA damage increased with incubation time (P=0.0011). Exposure of cells to the same concentration of DOX in the presence of 10-wt% P-105 showed no significant DNA damage for up to 9 h of incubation. However, when ultrasound was applied, a rapid and significant increase in DNA damage was observed (P=0.0001). The application of ultrasound causes the release of DOX from micelles or causes the HL-60 cells to take up the micelle encapsulated DOX. Our experiments indicated that the combination of DOX, ultrasound and pluronic P105 causes the largest DNA damage to HL-60 cells. We believe that this technique can be used for controlled drug delivery.