Gemcitabine in combination with paclitaxel for advanced soft-tissue sarcomas

Efficacy of Eribulin Plus Gemcitabine Combination in L-Sarcomas

Although the overall survival of advanced soft-tissue sarcoma (STS) patients has increased in recent years, the median progression-free survival is lower than 5 months, meaning that there is an unmet need in this population. Among second-line treatments for advanced STS, eribulin is an anti-microtubule agent that has been approved for liposarcoma. Here, we tested the combination of eribulin with gemcitabine in preclinical models of L-sarcoma. The effect in cell viability was measured by MTS and clonogenic assay. Cell cycle profiling was studied by flow cytometry, while apoptosis was measured by flow cytometry and Western blotting. The activity of eribulin plus gemcitabine was evaluated in in vivo patient-derived xenograft (PDX) models. In L-sarcoma cell lines, eribulin plus gemcitabine showed to be synergistic, increasing the number of hypodiploid events (increased subG1 population) and the accumulation of DNA damage. In in vivo PDX models of L-sarcomas, eribulin combined with gemcitabine was a viable scheme, delaying tumour growth after one cycle of treatment, being more effective in leiomyosarcoma. The combination of eribulin and gemcitabine was synergistic in L-sarcoma cultures and it showed to be active in in vivo studies. This combination deserves further exploration in the clinical context.

Use of patient derived orthotopic xenograft models for real-time therapy guidance in a pediatric sporadic malignant peripheral nerve sheath tumor

Background:

The aim of this study was to test the feasibility and utility of developing patient-derived orthotopic xenograft (PDOX) models for patients with malignant peripheral nerve sheath tumors (MPNSTs) to aid therapeutic interventions in real time.

Patient & Methods:

A sporadic relapsed MPNST developed in a 14-year-old boy was engrafted in mice, generating a PDOX model for use in co-clinical trials after informed consent. SNP-array and exome sequencing was performed on the relapsed tumor. Genomics, drug availability, and published literature guided PDOX treatments.

Results:

A MPNST PDOX model was generated and expanded. Analysis of the patient’s relapsed tumor revealed mutations in the MAPK1, EED, and CDK2NA/B genes. First, the PDOX model was treated with the same therapeutic regimen as received by the patient (everolimus and trametinib); after observing partial response, tumors were left to regrow. Regrown tumors were treated based on mutations (palbociclib and JQ1), drug availability, and published literature (nab-paclitaxel; bevacizumab; sorafenib plus doxorubicin; and gemcitabine plus docetaxel). The patient had a lung metastatic relapse and was treated according to PDOX results, first with nab-paclitaxel, second with sorafenib plus doxorubicin after progression, although a complete response was not achieved and multiple metastasectomies were performed. The patient is currently disease free 46 months after first relapse.

Conclusion:

Our results indicate the feasibility of generating MPNST-PDOX and genomic characterization to guide treatment in real time. Although the treatment responses observed in our model did not fully recapitulate the patient’s response, this pilot study identify key aspects to improve our co-clinical testing approach in real time.

A Gastric Cancer Peptide GX1-Modified Nano-Lipid Carriers Encapsulating Paclitaxel: Design and Evaluation of Anti-Tumor Activity

Aim

The aim of this study was to develop a GX1-modified nanostructured lipid carrier (NLCs) and to evaluate its ability to improve the anti-gastric cancer tumor effects of paclitaxel (PTX).

Main Methods

The GX1-modified NLCs were synthesized and loaded with PTX (GX1-PTX-NLCs) by emulsion solvent evaporation technique. The anti-tumor activity and pharmacodynamics were then evaluated by in vitro cell studies and animal experiments.

Key Findings

The GX1-modified NLCs were successfully synthesized and confirmed by ¹H NMR and MALDI-TOF-MS. PTX-loaded NLCs produced particles with average size distribution less than or equal to 222 nm and good drug loading and entrapment efficiency. In vitro studies demonstrated that GX1-PTX-NLCs had a more obvious inhibitory effect on Co-HUVEC cells than PTX and unmodified PTX-NLCs. The cellular uptake results also showed that GX1-PTX-NLCs were largely concentrated in Co-HUVEC cells, and the uptake rates of GX1-PTX-NLCs in Co-HUVEC were higher than those of the free drug and the PTX-NLC. In vivo studies demonstrated that GX1-PTX-NLCs possess strong anti-tumor effect and showed higher tumor growth inhibition and lower toxicity in nude mice.

Significance

These results suggest that GX1-modified NLCs enhanced the anti-tumor activity of PTX and reduced its toxicity effectively. GX1-PTX-NLCs may be considered as a potent drug delivery system for therapy of gastric cancer.

A Case of Unresectable Pulmonary Artery Intimal Sarcoma with Prolonged Survival by Chemotherapy

Pulmonary artery intimal sarcoma is a rare malignant tumor. Due to its low prevalence, little is known about efficacious systemic chemotherapies in cases where the tumors are unresectable or metastatic. In addition, the location of the disease can contribute to poor survival regardless of the response to therapy, as the tumor's position can cause pulmonary artery hypertension either rapidly or chronically. We encountered a case of unresectable pulmonary artery intimal sarcoma with lung metastases. Treatment with several cytotoxic agents resulted in prolonged survival of 14.2 months. Here, we report the clinical course of this case and present a review of the relevant literature.

Geridonin and paclitaxel act synergistically to inhibit the proliferation of gastric cancer cells through ROS-mediated regulation of the PTEN/PI3K/Akt pathway

Paclitaxel, a taxane, is a cytotoxic chemotherapeutic agent that targets microtubules. It has become a front-line therapy for a broad range of malignancies, including lung, breast, gastric, esophageal, and bladder carcinomas. Although paclitaxel can inhibit tumor development and improve survival, poor solubility, myelotoxicity, allergic reactions, and drug resistance have restricted its clinical application. Paclitaxel is frequently combined with other chemotherapeutics to enhance the antitumor effects and reduce side effects. We synthesized geridonin, a derivative of oridonin, and demonstrate that geridonin and paclitaxel act synergistically to inhibit the growth of gastric cancer cells. Importantly, geridonin enhanced the antitumor effects of paclitaxel without increasing toxicity in vivo. Mechanistic analysis revealed that administration of geridonin in combination with paclitaxel up-regulated the tumor suppressor PTEN and inhibited phosphorylation of Akt and MDM2. This led to the accumulation of p53 and induced apoptosis though the mitochondrial pathway. Thus, geridonin in combination with paclitaxel is a new treatment strategy for gastric cancer.