Treatment Of Lewis Lung Carcinoma Research Articles

Pharmacokinetic study of Tdp1 inhibitor resulted in a significant increase in antitumor effect in the treatment of Lewis lung carcinoma in mice by its combination with topotecan

We have previously shown that the Tdp1 inhibitor, enamine derivative of usnic acid, the agent OL9–116, enhances the antitumor activity of topotecan. In the present study, we developed and validated LC-MS/MS method for the quantification of OL9–116 in mouse whole blood and studied pharmacokinetics of the agent. The substance OL9–116 was shown to be stable in the whole blood in vitro. Sample preparation included two steps: mixing 10 µL of a blood sample with 10 µL of 0.2 M ZnSO4 aqueous solution, followed by protein precipitation with 100 µL of acetonitrile containing internal standard. Quantification of the compound was performed using SCIEX 6500 QTRAP mass spectrometer in MRM mode following chromatographic separation on a C8 reversed-phase column. The method was validated in terms of selectivity, linearity, accuracy, precision, recovery, and stability of the prepared sample. When the agent OL9–116 was administered intragastrically at a dose of 150 mg/kg, the maximum concentration in the blood (about 5000 ng/mL) was reached after 2–4 h followed by the distribution and elimination of the compound. A study of the antitumor activity of a combination of OL9–116 and topotecan against Lewis lung carcinoma revealed that administration of topotecan 3 h after OL9–116 resulted in the most pronounced antitumor effect compared to simultaneous or individual administration of both compounds.

First Polynuclear Palladium Compounds [(C5H12NO)(PdCl3)]n and [(C10H16NO)2(Pd2Cl6)] with High Antitumor and Radioprotective Activity

Polymeric palladium complexes [(C5H12NO)(PdCl3)]n (I) and [(C10H16NO)2(Pd2Cl6)] (II) were synthesized for the first time and studied by X-ray diffraction. Complexes I and II were found to have moderate toxicity (3rd class of toxicity) and high antitumor and radioprotective activities. Treatment of Lewis lung carcinoma (LLC) with I and II induced statistically significant antitumor and antimetastatic effects exceeding those of cisplatin: the use of I and II retarded the growth of LLC by 60.0%, while cisplatin retarded it by 48.0%. The decrease in the LLC metastasis was 75% upon the action of I, 91.0% in the case of II, and 69.0% for cisplatin. It was shown that II has a clear-cut radioprotective action. On single exposure of mice to a dose of 8.2 Gy, their survival rate was 58.0% versus 4.5% for the control. Fractional exposure to increasing doses (2.5, 3, and 3.5 Gy) resulted in 75.0% survival rate versus 33.0% for the control.

Efficacy of granulocyte-macrophage colony-stimulating factor combined with metronomic paclitaxel in the treatment of Lewis lung carcinoma transplanted in mice.

Metronomic chemotherapy in combination with immunotherapy is an attractive approach in cancer therapy. The purpose of the present study was to investigate the anti-tumor effect of granulocyte-macrophage colony-stimulating factor (GM-CSF) in combination with metronomic paclitaxel (MET PTX) on Lewis lung carcinoma transplanted in mice. In the present study, tumor-bearing mice survival time and tumor growth were monitored. The day after the end of the treatment, white blood cells were counted, and the number and maturation of dendritic cell were determined by flow cytometry. Besides, microvessel density and tumor cell proliferation were determined by immunohistochemistry, while apoptosis was determined by TUNEL (Terminal deoxynucleotidyl transferase-mediated nick end labeling) assay. Micro 18F-FDG PET/CT (18F-Fluorodeoxyglucose positron emission tomography/computed tomography) was used to obtain SUVmax values. White blood cells reduction was not observed in the mice treated with GM-CSF combined with MET PTX. Moreover, GM-CSF combined with MET PTX further reduced proliferation and microvessel density, promoted tumor apoptosis, increased the dendritic cells number and induced their maturation, with concomitant delay in tumor growth and improved survival. Taken together, GM-CSF combined with MET PTX exerted a synergistic anti-tumor effect against lung cancer in a mouse model through an antiangiogenic activity and inducing dendritic cells maturation without exerting pronounced adverse effects. Hence, combined metronomic chemotherapy and immunotherapy could be a potential strategy for the treatment of patients with advanced lung cancer.

Danshensu, a major water-soluble component of Salvia miltiorrhiza, enhances the radioresponse for Lewis Lung Carcinoma xenografts in mice.

The molecule 3-(3,4-dihydroxyphenyl)-2-hydroxypropanoic acid (danshensu), a herbal preparation used in traditional Chinese medicine, has been found to possess potential antitumor and anti-angiogenesis effects. The aim of the present study was to investigate the efficacy of the combination of radiation therapy (RT) with danshensu in the treatment of Lewis lung carcinoma (LLC) xenografts, whilst exploring and evaluating the mechanism involved. In total, 8-week old female C57BL/6J mice were randomly assigned into 3 groups to receive: RT, RT + cisplatin and RT + danshensu, respectively, when LLC reached 100–150 mm3. Each group was divided into 7 subgroups according to the different irradiation doses that were administered. Tumor growth curves were created and the sensitization enhancement ratios of the drugs were calculated. The experiment was then repeated, and the 4 groups of tumor-bearing mice were treated with natural saline, danshensu, RT + danshensu and RT, respectively. The mice were sacrificed on day 7, and tumor tissue and blood were collected to determine microvessel density, the expression of proangiogenic factors, and the levels of blood thromboxane B2 and 6-keto-prostaglandin-F1α. Tumor hypoxia was also detected using in vivo fluorescence imaging. With respect to LLC xenografts, treatment with danshensu + RT significantly enhanced the effects of tumor growth inhibition (P<0.05). Furthermore, tumor vasculature was remodeled and microcirculation was improved, which significantly reduced tumor hypoxia (P<0.05). The present study demonstrated that danshensu significantly enhanced the radioresponse of LLC xenografts in mice. The mechanism involved may be associated with the alleviation of tumor cell hypoxia following treatment with danshensu + RT, caused by the improvement of tumor microcirculation and the remodeling of tumor vasculature.

2-DEOXY-D-GLUCOSE ENHANCES DICHLOROACETATE ANTITUMOR ACTION AGAINST LEWIS LUNG CARCINOMA

Aerobic glycolysis that supports high proliferation rate and survival of tumor cells in unfavorable conditions is among fundamental features of tumor metabolism. The search for active modulators of energetic metabolism capable of suppressing tumor growth and metastasis could result in higher effectiveness of anticancer therapy. To study antitumor and antimetastatic activity of the modulators of energetic metabolism dichloroacetate (DCA) and 2-deoxy-D-glucose (2DG) used in combination treatment of Lewis lung carcinoma (LLC). As experimental tumor model, LLC/R9 variant was used. DCA and 2DG were administered per os to С57Bl/6 mice 5 times per week for 3 weeks at a total dose of 1.5 and 0.98 g/kg, respectively, as single agents or in combination starting from the following day after tumor cell transplantation. Growth of primary tumor and number and volume of lung metastases were registered. Lactate and pyruvate content was determined by enzymatic methods using lactate dehydrogenase. Electron paramagnetic resonance was used for analyzing the functional state of the components of mitochondrial respiratory chain. Engulfing activity and reactive oxygen species (ROS) production in tumor-associated CD14(+) cells was analyzed by flow cytometer with the use of FITC-labeled staphylococcus, and by spectrofluorometry with the use of 2.7-dichlorofluorescein diacetate, respectively. DCA administered as a single agent did not affect primary tumor growth but decreased the number and volume of lung metastases by 60% (p < 0.05) and 90% (p < 0.05), respectively. In mice treated with 2DG only, primary tumor volume as well as the number and volume of lung metastases were not affected. Combination treatment with DCA and 2DG resulted in the decrease of primary tumor volume, the number and volumes of lung metastases by 70; 46, and 90%, respectively (p < 0.05). High antitumor activity of DCA + 2DG was associated with 31% decrease (p < 0.05) of lactate content in tumor tissue and 120% increase (p < 0.01) of ROS production in CD14(+) cells recruited to the region of tumor growth. 2DG that possesses neither antitumor nor antimetastatic activity against LLC/R9 significantly enhanced antitumor activity of DCA with accompanying inhibition of glycolysis and increase of cytotoxic activity of CD14(+) cells infiltrating tumor tissue. Taking into account significant antimetastatic activity of DCA this substance could be considered as a promising antimetastatic agent.

Radio frequency radiation-induced hyperthermia using Si nanoparticle-based sensitizers for mild cancer therapy.

Offering mild, non-invasive and deep cancer therapy modality, radio frequency (RF) radiation-induced hyperthermia lacks for efficient biodegradable RF sensitizers to selectively target cancer cells and thus avoid side effects. Here, we assess crystalline silicon (Si) based nanomaterials as sensitizers for the RF-induced therapy. Using nanoparticles produced by mechanical grinding of porous silicon and ultraclean laser-ablative synthesis, we report efficient RF-induced heating of aqueous suspensions of the nanoparticles to temperatures above 45-50°C under relatively low nanoparticle concentrations (<1 mg/mL) and RF radiation intensities (1–5 W/cm2). For both types of nanoparticles the heating rate was linearly dependent on nanoparticle concentration, while laser-ablated nanoparticles demonstrated a remarkably higher heating rate than porous silicon-based ones for the whole range of the used concentrations from 0.01 to 0.4 mg/mL. The observed effect is explained by the Joule heating due to the generation of electrical currents at the nanoparticle/water interface. Profiting from the nanoparticle-based hyperthermia, we demonstrate an efficient treatment of Lewis lung carcinoma in vivo. Combined with the possibility of involvement of parallel imaging and treatment channels based on unique optical properties of Si-based nanomaterials, the proposed method promises a new landmark in the development of new modalities for mild cancer therapy.

Therapeutic potential of bone marrow-derived mesenchymal stem cells producing pigment epithelium-derived factor in lung carcinoma

Specific and efficient gene delivery to target cells and the subsequent expression of the RNA and protein is crucial to the success of gene-based therapy for cancer. Mesenchymal stem cells (MSCs) represent novel and efficient tools for delivery of therapeutic agents to tumor cells. In this study, we evaluated the potential of bone marrow-derived mesenchymal stem cells, genetically modified to express pigment epithelium-derived factor (PEDF) for the treatment of Lewis lung carcinoma (LLC). MSCs derived from murine bone marrow were efficiently engineered to express human PEDF by adenoviral transduction, and the expression and bioactivity of the transgenic protein from engineered MSCs were confirmed in vitro. Animal experiments showed that the systemic administration of MSCs treated with PEDF dramatically reduced the growth of LLC tumors and significantly prolonged survival. Immunohistochemistry analysis of the tumors from MSC-PEDF-treated animals indicated an increase in apoptosis and a decrease in microvessel density. ELISA showed that the group of MSCs treated with PEDF had relatively higher expression levels of PEDF in tumor tissue and lower levels in serum compared with the free Ad-PEDF group. These results suggest that MSCs have potential use as effective delivery of vehicles for therapeutic genes in the treatment of LLC.

MTHPC-mediated photodynamic treatment of Lewis lung carcinoma in vitro and in vivo

The ongoing search for the enhancement of efficacy of photodynamic therapy stimulates the interest in molecular mechanisms of the response to the treatment. Looking for the cell line suitable for investigation of cellular response both in vivo and in vitro, we evaluated phototoxicity of m-tetrakis-(3-hydroxyphenyl)-chlorin (mTHPC) on viability of Lewis lung carcinoma (LLC1) cells in vitro, growth of murine transplantable tumor, and mice survival. LLC1 cell culture and male C57BL/6 mice bearing Lewis lung carcinoma were used for the experiments. Photodynamic treatment was mediated by m-tetrakis-(3-hydroxyphenyl)-chlorin as a photosensitizer. Light emitting diode array was used for illumination. The effect of the photodynamic treatment was evaluated by comparison of viability of control and treated cells, growth of tumors, and survival of the control and treated mice. In vitro, a cytotoxic dose inducing a reduction in viability of LLC1 cells by 50% was achieved at 60 mJ/cm(2) and approximately 400 ng/mL of the photosensitizer, or 30 mJ/cm(2) and 600 ng/mL of mTHPC. Both the concentration of the photosensitizer and duration of light exposure were significant determinants of cytotoxic effect. In vivo, an injection of 0.25 mg/kg of mTHPC to mice bearing Lewis lung tumor and illumination at 120 J/cm(2) taking place after 24 h significantly inhibited tumor growth and prolonged mice survival. However, the tumors regained their growth potential after 9 days. Photodynamic treatment mediated by m-tetrakis-(3-hydroxyphenyl)-chlorin had a significant effect on LLC1 cells in vitro and growth of Lewis lung carcinoma in vivo.

Treatment of Lewis lung carcinoma by photodynamic therapy and glucan from barley

During the photodynamic treatment, complement system is activated and tumor cells are opsonized with iC3b fragment. beta-glucans can enhance cytotoxicity of iC3b-opsonized cells due to their specific interaction with complement receptor 3 (CR3; CD11b/CD18) on the surface of the effector cells. In contrast to microorganisms, tumor cells lack beta-glucan as a surface component and cannot trigger complement receptor 3-dependent cellular cytotoxicity and initiate tumor-killing activity. This mechanism could be induced in the presence of beta-glucans. This study aimed at determining the influence of coadministration of beta-glucan from barley on the efficacy of photodynamic tumor therapy (PDT). C57 Bl/6 female mice bearing Lewis lung carcinoma were used throughout the study. Mice were randomized into groups (15 in each group) and exposed to the treatment with intravenous Photofrin injection (dose, 10 mg/kg) and after 24 h following laser illumination, or with oral administration of beta-glucan from barley at a dose of 400 microg/mouse per day up to 5 days, or with their combination. Tumor growth dynamics and survival of the treated and untreated mice were monitored. Tumor volume in all treated groups was significantly lower (P<0.001) than that in the control group. The most effective tumor growth suppression (P=0.033) was achieved in mice treated with combination of PDT and beta-glucan from barley as compared with PDT alone. The best survival was achieved in the same group, but difference was not significant as compared to the control group (P=0.143) and to PDT alone group (P=0.319). The present study demonstrates that coadministration of beta-glucan from barley can enhance efficacy of photodynamic therapy.

Electrical treatment of Lewis lung carcinoma in mice

Direct electrical current of sufficient magnitude and duration can destroy tissue. This capability may be clinically useful in some cases involving inoperable metastatic lesions. In principle, a tumor could be treated with direct current administered via a percutaneous electrode insulated along its entire length except for the portion actually inserted into the tumor. An animal model was developed to study the effect of direct electrical current on tumor growth. The growth of implanted Lewis lung carcinoma in mice was inhibited following the administration of 2 mA for 1 hr, 1–3 treatments. The effect occurred in both small and large tumors. The results suggest that the electrical technique is potentially useful for treating some tumors.

Response of mouse tumor to interferon inducer and radiation

The antitumor eflect of interferon inducer poly(ICLC), given prior to the radiation treatment of Lewis lung carcinoma in C 57Bl mice was studied. To induce the tumors, the mice were injected subcutaneously into the hind leg with 3 × 10 4 or 3 × 10 5 tumor cells. The combination treatment consisted of poly(ICLC) given at 1.25 mg/kg 6 hours before 400 cGy of 60Co gamma rays. All treatments were given three times over 1.5 weeks. The local response, as measured by the delay in the tumor growth, was significantly higher in the combination treatment group than in poly(ICLC) or local irradiation groups. Following the termination of treatment, tumor regrowth was observed. The survival of poly(ICLC) treated mice was influenced by the number of transplanted tumor cells. Thus, untreated mice which received 3 × 10 4 or 3 × 10 5 (2 or 20 TD 50) of tumor cells had similar mean survival time of 25.4 ± 1.9 and 22 ± 84 days, respectively ( p > 0.05). The mice, treated by a combination of poly(ICLC) and local irradiation survived 48.2 ± 2.1 days and 30.7 ± 1.2 days ( p < .01), with higher survival in 2 TD 50 tumor cell groups. Thus, data obtained in this study in mice showed that administration of an interferon inducer poly(ICLC) prior to local irradiation can improve tumor response and survival.

Synergistic effect of K-18 and concomitant hyperthermia for treatment of lewis lung carcinoma in mice

We investigated the synergistic anti-tumor effects of K-18 (conjugate of human gamma-globulin and melphalan) and concomitantly administered hyperthermia on Lewis lung carcinoma in mice. The antitumor effect of a subeffective dose of K-18 or an equivalent dose of melphalan alone was enhanced by local hyperthermia. K-18 administration demonstrated a greater potentiation for inhibition of tumor growth than that of melphalan alone. Local hyperthermia plus K-18 reduced the dose of melphalan required for tumor growth inhibition by melphalan alone. The combined application of K-18 and hyperthermia for treating cancer warrants further study.

Flow-cytometric analysis of DNA distribution after VP16-213 treatment of Lewis lung carcinoma.

The two dosage schedules of VP16 that gave the least and the greatest efficacy in Lewis lung carcinoma of the mouse were selected for evaluation of the cytokinetic effects observable in vivo at different intervals after treatment (schedule A: 40 mg/kg IV, on day 8 after transplant; schedule B: 13 mg/kg IV, repeated on days 8, 11, and 14 after transplant). After the single dose and after each repeated dose there was a marked increase in the percentage of cells in the LS-G2-M phases, with a corresponding decrease in the percentage of cells in G0-G1. The number of neoplastic tetraploid cells compared with normal diploid cells in the tumor was reduced after the single IV dose, and more markedly so after repeated doses. This study suggests that the more marked delay of cancer cell growth and greater effectiveness observed with schedule B is related to repeated blockage of the LS-G2-M phases.

Effect of administration schedule on the levan-cyclophosphamide combined treatment of Lewis lung carcinoma

Combined treatment with laven and cyclophosphamide (CY) was applied intratumorally to Lewis lung carcinoma tumors in C57B1 mice on day 5 after tumor cell inoculation. Although on that day levan alone had no effect and CY alone caused only temporary regression of tumors, the combined CY-levan treatment caused 60% cure. Levan given before CY was almost as effective as simultaneous administration of both drugs on day 5. Delaying the administration of levan after CY treatment reduced the therapeutic effect. It is concluded that timing in relation to tumor cell inoculation as well as the order of administration of drugs, determine the degree of therapeutic efficacy. In tumor chemo-immunotheraphy the final effect is probably due not only to the anti-tumoral effect per se of each drug, but also to the fact that the two agents have an effect on the immune system. Since the immune response may change during tumor development, the effect of timing of administration of an immunomudulator and certainly, can be crucial.

Combined treatment of Lewis lung carcinoma by tumor excision and levan.

A combined treatment modality including surgical excision and daily injections of high molecular levan seemed to be effective against Lewis lung carcinoma in C57BL mice. The inhibitory effect of levan on tumor growth in mice treated by resection of the primary tumor was demonstrated as follows: (1) recurrence of primary tumors was less in levan-treated mice compared to untreated animals; (2) metastases were less numerous in the levan-treated animals; (3) levan treatment partly prevented loss in body weight, and (4) it increased the survival rate. Recurrence of primary tumors appeared to be more efficiently inhibited by local levan treatment, while systemic (i.p.) administration was more effective than local treatment in preventing metastases. The mechanism of inhibition of tumor growth was related to accumulation of macrophages around the metastases.