SciCombinator

Discover the most talked about and latest scientific content & concepts.

Concept: Cisplatin

241

Background Osimertinib is an epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) that is selective for both EGFR-TKI sensitizing and T790M resistance mutations in patients with non-small-cell lung cancer. The efficacy of osimertinib as compared with platinum-based therapy plus pemetrexed in such patients is unknown. Methods In this randomized, international, open-label, phase 3 trial, we assigned 419 patients with T790M-positive advanced non-small-cell lung cancer, who had disease progression after first-line EGFR-TKI therapy, in a 2:1 ratio to receive either oral osimertinib (at a dose of 80 mg once daily) or intravenous pemetrexed (500 mg per square meter of body-surface area) plus either carboplatin (target area under the curve, 5 [AUC5]) or cisplatin (75 mg per square meter) every 3 weeks for up to six cycles; maintenance pemetrexed was allowed. In all the patients, disease had progressed during receipt of first-line EGFR-TKI therapy. The primary end point was investigator-assessed progression-free survival. Results The median duration of progression-free survival was significantly longer with osimertinib than with platinum therapy plus pemetrexed (10.1 months vs. 4.4 months; hazard ratio; 0.30; 95% confidence interval [CI], 0.23 to 0.41; P<0.001). The objective response rate was significantly better with osimertinib (71%; 95% CI, 65 to 76) than with platinum therapy plus pemetrexed (31%; 95% CI, 24 to 40) (odds ratio for objective response, 5.39; 95% CI, 3.47 to 8.48; P<0.001). Among 144 patients with metastases to the central nervous system (CNS), the median duration of progression-free survival was longer among patients receiving osimertinib than among those receiving platinum therapy plus pemetrexed (8.5 months vs. 4.2 months; hazard ratio, 0.32; 95% CI, 0.21 to 0.49). The proportion of patients with adverse events of grade 3 or higher was lower with osimertinib (23%) than with platinum therapy plus pemetrexed (47%). Conclusions Osimertinib had significantly greater efficacy than platinum therapy plus pemetrexed in patients with T790M-positive advanced non-small-cell lung cancer (including those with CNS metastases) in whom disease had progressed during first-line EGFR-TKI therapy. (Funded by AstraZeneca; AURA3 ClinicalTrials.gov number, NCT02151981 .).

Concepts: Central nervous system, Epidemiology, Cancer, Signal transduction, Lung cancer, Epidermal growth factor receptor, Epidermal growth factor, Cisplatin

81

Cancer stem cells are capable of transformation after apoptosis through the blebbishield emergency program. Reactive oxygen species (ROS) play an essential role in transformation. Understanding how ROS are linked to blebbishield-mediated transformation is necessary to develop efficient therapeutics that target the resurrection of cancer stem cells. Here we demonstrate that a novel PKC-ζ to p47(phox) interaction is required for ROS production in cancer cells. The combined use of the S6K inhibitor BI-D1870 with TNF-α inhibited the PKC-ζ to p47(phox) interaction, inhibited ROS production, degraded PKC-ζ, and activated caspases-3 and -8 to block transformation from blebbishields. BI-D1870 also inhibited transformation from cycloheximide-generated blebbishields. Thus ROS and the PKC-ζ to p47(phox) interaction are valid therapeutic targets to block transformation from blebbishields.

Concepts: Oxygen, Cancer, Oncology, Mitochondrion, Cell division, Stroke, Reactive oxygen species, Cisplatin

75

Osteosarcoma is a rare disease diagnosed as malignant bone tumor. It is generally refractory to chemotherapy, which contributes to its poor prognosis. The reversal of chemoresistance is a major clinical challenge to improve the prognostic outcome of osteosarcoma patients. We developed a tumor-specific replication-competent oncolytic adenovirus, OBP-301 (telomelysin) and assessed its synergistic effects with chemotherapeutic agents (cisplatin and doxorubicin) using human osteosarcoma cell lines and a xenograft tumor model. The molecular mechanism underlying the chemosensitizing effect of OBP-301 was evaluated in aspects of apoptosis induction. OBP-301 inhibits anti-apoptotic myeloid cell leukemia 1 (MCL1) expression, which in turn leads to chemosensitization in human osteosarcoma cells. The siRNA-mediated knockdown of MCL1 expression sensitized human osteosarcoma cells to common chemotherapeutic agents. We also found that upregulation of microRNA-29 targeting MCL1 via virally induced transcriptional factor E2F-1 activation was critical for the enhancement of chemotherapy-induced apoptosis in osteosarcoma cells. Telomerase-specific oncolytic adenovirus synergistically suppressed the viability of human osteosarcoma cells in combination with chemotherapeutic agents. The combination treatment also significantly inhibited tumor growth, as compared to monotherapy, in an osteosarcoma xenograft tumor model. Our data suggest that replicative virus-mediated tumor-specific MCL1 ablation may be a promising strategy to attenuate chemoresistance in osteosarcoma patients.

Concepts: DNA, Gene, Cell, Cancer, Oncology, Chemotherapy, Cisplatin, Osteosarcoma

52

The mortality and morbidity rates of pancreatic cancer are high because of its extremely invasive and metastatic nature. Its lack of symptoms, late diagnosis and chemo-resistance and the ineffective treatment modalities warrant the development of new chemo-therapeutic agents for pancreatic cancer. Agents from medicinal plants have demonstrated therapeutic benefits in various human cancers. Nimbolide, an active molecule isolated from Azadirachta indica, has been reported to exhibit several medicinal properties. This study assessed the anticancer properties of nimbolide against pancreatic cancer. Our data reveal that nimbolide induces excessive generation of reactive oxygen species (ROS), thereby regulating both apoptosis and autophagy in pancreatic cancer cells. Experiments with the autophagy inhibitors 3-methyladenine and chloroquine diphosphate salt and the apoptosis inhibitor z-VAD-fmk demonstrated that nimbolide-mediated ROS generation inhibited proliferation (through reduced PI3K/AKT/mTOR and ERK signaling) and metastasis (through decreased EMT, invasion, migration and colony forming abilities) via mitochondrial-mediated apoptotic cell death but not via autophagy. In vivo experiments also demonstrated that nimbolide was effective in inhibiting pancreatic cancer growth and metastasis. Overall, our data suggest that nimbolide can serve as a potential chemo-therapeutic agent for pancreatic cancer.

Concepts: Immune system, Cancer, Breast cancer, Metastasis, Oncology, Apoptosis, Inhibitor, Cisplatin

28

The standard chemotherapy for Japanese patients with extensive disease of small-cell lung cancer (ED-SCLC) is cisplatin and irinotecan.

Concepts: Epidemiology, Cancer, Metastasis, Lung cancer, Carcinoma, Cisplatin, Small cell carcinoma, Carboplatin

28

Double emulsion has been used most often in formulation of hydrophilic drugs by nanoparticles of biodegradable polymers, which has disadvantages such as low drug loading and low drug encapsulation efficiency due to the drug loss in the process. The drug release may be too fast for sustained chemotherapy. We developed in this research a d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) prodrug micelle system with cisplatin as a model hydrophilic drug. We demonstrated that such a system can successfully deliver the model hydrophilic drug with a low critical micelle concentration (CMC) of only 5.01mg/L, a high drug load of 4.95% (w/w) and a pH-responsive drug release kinetics and higher cellular uptake in comparison with the original drug and the TPGS-cisplatin prodrug itself. The cell viability experiment showed great enhancement of the cisplatin chemotherapy, which is demonstrated by the IC50 value reduced from 3.95, 0.98, 0.19 for cisplatin to 1.36, 0.51, 0.08μg/mL for the TPGS prodrug micelle formulation after 24, 48, 72h culture with the HepG2 hepatocarcinoma cells, respectively. Furthermore, such a TPGS prodrug micellar formulation showed significant neuroprotective effects for the cisplatin chemotherapy, which is demonstrated by the greatly increased IC50 value for the SH-SY5Y neuroblast-like cells in comparison between cisplatin and the TPGS prodrug micelle formulation. The TPGS prodrug micelles can also be generalized to become a new strategy for codelivery of hydrophilic and hydrophobic drugs and/or imaging agents.

Concepts: Pharmacology, Hydrophobic effect, Surfactant, Micelle, Vesicle, Cisplatin, Colloidal chemistry, Critical micelle concentration

27

Most hypoxic tumors are insensitive to radiations, which is a major obstacle in the development of conventional radiotherapy for tumor treatments. Some anticancer drugs, such as cisplatin (CDDP), have been extensively used as an anticancer drug and in the meantime radiosensitizer as well clinically to enhance radiotherapy. Herein, we develop rattle-structured multifunctional upconversion core/porous silica shell nanotheranostics (UCSNs) for delivering CDDP to tumors for synergetic chemo-/radiotherapy by CDDP-radiosensitization and magnetic/luminescent dual-modal imaging. UCSNs had a DLS diameter of 79.1 nm and excellent water dispersity and stability. In vitro studies showed that CDDP loaded in UCSNs (UCSNs-CDDP) was found to be more effective than free CDDP as a radiosensitizer. After injection, UCSNs-CDDP also demonstrated unambiguously enhanced radiotherapy efficacy in vivo. Our report aims at presenting a novel strategy in biomedical nanotechnology that allows simultaneous dual-modal imaging and localized therapy via synergetic chemo-/radiotherapy, which may achieve the optimized therapeutic efficacy in cancer treatment.

Concepts: Cancer, Oncology, Chemotherapy, Radiation therapy, In vitro, Cisplatin

26

The newly synthesized naftopidil analogue HUHS1015 reduced cell viability in malignant pleural mesothelioma cell lines such as MSTO-211H, NCI-H28, NCI-H2052, and NCI-H2452 cells, with the potential greater than that for the anticancer drugs paclitaxel or cisplatin at higher concentrations more than 30 μM. HUHS1015 induced both necrosis and apoptosis of MSTO-211H and NCI-H2052 cells. HUHS1015 upregulated expression of mRNAs for Puma, Hrk, and Noxa in MSTO-211H and NCI-H2052 cells, suggesting HUHS1015-induced mitochondrial apoptosis. HUHS1015 clearly suppressed tumor growth in mice inoculated with NCI-H2052 cells. Taken together, the results of the present study indicate that HUHS1015 could be developed as an effective anticancer drug for treatment of malignant pleural mesothelioma. This article is protected by copyright. All rights reserved.

Concepts: DNA, Gene expression, Cancer, Oncology, Cell biology, Apoptosis, Chemotherapy, Cisplatin

26

Non-small-cell lung carcinomas do not sufficiently respond to cancer chemotherapeutic drugs. Combination effects of cancer chemotherapy drugs (paclitaxel and carboplatin) with nobiletin or powdered Shiikuwasha extract from Citrus depressa were examined by isobologram and combination index analyses. It was demonstrated that the combination generated a synergistic inhibitory effect against the proliferation of the human non-small-cell lung carcinoma cell lines A549 and H460 and that of the two chemotherapy drugs, paclitaxel was responsible for this synergistic effect. Furthermore, the percentage of apoptotic cells was decreased with increasing rates of nobiletin to paclitaxel and carboplatin. These findings were considered to be attributed to the ability of nobiletin to regulate cells in the G1 phase, which escaped cell death initiated by paclitaxel and carboplatin. An antitumor activity assay showed that this combination significantly suppressed the growth of subcutaneous A549 tumor xenografts in nude mice.

Concepts: Cancer, Metastasis, Oncology, Lung cancer, Chemotherapy, Carcinoma, Cisplatin, Paclitaxel

24

The present study focuses on biodistribution profile and pharmacokinetic parameters of EGFR-targeted chitosan nanoparticles (TG CS nanoparticles) for siRNA/cisplatin combination therapy of lung cancer.

Concepts: Epidemiology, Cancer, Metastasis, Lung cancer, Cancer staging, Tobacco smoking, Cisplatin, Carboplatin