Effects of vinorelbine on epidermal growth factor-receptor binding of human breast cancer cell lines in vitro

Vinorelbine Alters lncRNA Expression in Association with EGFR Mutational Status and Potentiates Tumor Progression Depending on NSCLC Cell Lines' Genetic Profile

Lung cancer remains the leading cause of cancer-related mortality worldwide, with non-small cell lung cancer (NSCLC) as the most common type. In addition, NSCLC has a high mortality rate and an overall adverse patient outcome. Although significant improvements have been made in therapeutic options, effectiveness is still limited in late stages, so the need for a better understanding of the genomics events underlying the current therapies is crucial to aid future drug development. Vinorelbine (VRB) is an anti-mitotic chemotherapy drug (third-generation vinca alkaloid) used to treat several malignancies, including NSCLC. However, despite its widespread clinical use, very little is known about VRB-associated genomic alterations in different subtypes of NSCLC. This article is an in vitro investigation of the cytotoxic effects of VRB on three different types of NSCLC cell lines, A549, Calu-6, and H1792, with a closer focus on post-treatment genetic alterations. Based on the obtained results, VRB cytotoxicity produces modifications on a cellular level, altering biological processes such as apoptosis, autophagy, cellular motility, cellular adhesion, and cell cycle, but also at a genomic level, dysregulating the expression of some coding genes, such as EGFR, and long non-coding RNAs (lncRNAs), including CCAT1, CCAT2, GAS5, MALAT1, NEAT1, NORAD, XIST, and HOTAIR, that are implicated in the mitogen-activated protein kinase (MAPK) signaling pathway. Therefore, although extensive validation is required, these results pave the way towards a better understanding of the cellular and genomic alterations underlying the cytotoxicity of VRB.

Two-layer modular analysis of gene and protein networks in breast cancer

Background

Genomic, proteomic and high-throughput gene expression data, when integrated, can be used to map the interaction networks between genes and proteins. Different approaches have been used to analyze these networks, especially in cancer, where mutations in biologically related genes that encode mutually interacting proteins are believed to be involved. This system of integrated networks as a whole exhibits emergent biological properties that are not obvious at the individual network level. We analyze the system in terms of modules, namely a set of densely interconnected nodes that can be further divided into submodules that are expected to participate in multiple biological activities in coordinated manner.

Results

In the present work we construct two layers of the breast cancer network: the gene layer, where the correlation network of breast cancer genes is analyzed to identify gene modules, and the protein layer, where each gene module is extended to map out the network of expressed proteins and their interactions in order to identify submodules. Each module and its associated submodules are analyzed to test the robustness of their topological distribution. The constituent biological phenomena are explored through the use of the Gene Ontology. We thus construct a “network of networks”, and demonstrate that both the gene and protein interaction networks are modular in nature. By focusing on the ontological classification, we are able to determine the entire GO profiles that are distributed at different levels of hierarchy. Within each submodule most of the proteins are biologically correlated, and participate in groups of distinct biological activities.

Conclusions

The present approach is an effective method for discovering coherent gene modules and protein submodules. We show that this also provides a means of determining biological pathways (both novel and as well those that have been reported previously) that are related, in the present instance, to breast cancer. Similar strategies are likely to be useful in the analysis of other diseases as well.

Results of nimotuzumab and vinorelbine, radiation and re-irradiation for diffuse pontine glioma in childhood

Radiotherapy is the only treatment definitely indicated for diffuse pontine gliomas (DIPG). Findings on the role of EGFR signaling in the onset of childhood DIPG prompted the use of nimotuzumab, an anti-EGFR monoclonal antibody. Assuming a potential synergy with both radiotherapy and vinorelbine, a pilot phase 2 protocol was launched that combined nimotuzumab with concomitant radiation and vinorelbine. An amendment in July 2011 introduced re-irradiation at relapse. The primary endpoint for first-line treatment was objective response rate (CR + PR + SD) according to the RECIST. This report concerns the outcome of this strategy as a whole. Vinorelbine 20 mg/m(2) was administered weekly, with nimotuzumab 150 mg/m(2) in the first 12 weeks of treatment; radiotherapy was delivered from weeks 3 to 9, for a total dose of 54 Gy. Vinorelbine 25 mg/m(2) and nimotuzumab were given every other week thereafter until the tumor progressed or for up to 2 years. Re-irradiation consisted of 19.8 Gy, fractionated over 11 days. Baseline and latest MRIs were assessed blindly by an outside neuroradiologist. Twenty five children (mean age 7.4 years) were enrolled as of August 2009 (median follow-up 29 months). A response was observed in 24/25 patients (96 %). The nimotuzumab/vinorelbine combination was very well tolerated, with no acute side-effects. Eleven of 16 locally-relapsing patients were re-irradiated. One-year PFS and OS rates were 30 ± 10 % and 76 ± 9 %, respectively; 2-year OS was 27 ± 9 %; the median PFS and OS were 8.5 and 15 months, respectively. This strategy generated interesting results and warrants further investigation.

The predictive value of epidermal growth factor receptor expression for sensitivity to vinorelbine in breast cancer

Breast cancer patients with positive epidermal growth factor receptor (EGFR) expression have significantly worse post-relapse prognosis than patients with negative EGFR expression. Vinorelbine (NVB) is usually reserved as a salvage therapy after anthracyclines and taxanes in patients with breast cancer. To see whether EGFR expression has a predictive value in NVB-mediated effect on human breast cancer cells, we examined 50 primary breast cancer samples. Of these, 42% were found to be NVB sensitive by ATP-tumour chemosensitivity assay. Sensitivity was correlated with EGFR expression level (p = 0.001). To dynamically examine EGFR's effect on NVB sensitivity in breast cancer cells, we used the real-time cell electronic sensing system with EGFR-positive and EGFR-negative breast cancer cell lines, MCF-7 and MDA-MB-435s, respectively. MCF-7 is NVB sensitive, while MDA-MB-435 is NVB resistant. NVB-induced cytotoxicity to MCF-7 can be partly reversed with inhibitory anti-EGFR antibody. NVB up-regulated EGFR expression in MCF-7 cells, which affects ERK1/2 phosphorylation. This cellular response mechanism may cause greater input to non-lethally damaged cells. These data suggest that EGFR expression can be used as a prognostic factor for breast cancer sensitivity to NVB, which could help identify appropriate treatments for breast cancer.

A phase I evaluation of the combination of vinflunine and erlotinib in patients with refractory solid tumors

PURPOSE

Epidermal growth factor receptor (EGFR) inhibition may overcome chemotherapy resistance by inhibiting important anti-apoptotic signals that are constitutively activated by an overstimulated EGFR pathway.

METHODS

This phase I dose escalation trial assessed the safety and efficacy of vinflunine, a novel vinca alkaloid microtubule inhibitor, with erlotinib, an EGFR tyrosine kinase inhibitor, in patients with refractory solid tumors.

RESULTS

Seventeen patients were treated, 10 with continuous erlotinib, and 7 with intermittent erlotinib. At dose level 1, vinflunine 280 mg/m(2) IV day 1 and erlotinib 75 mg PO days 2-21 ("continuous erlotinib") in 21 day cycles, two of four patients experienced DLTs. At dose level -1 (vinflunine 250 mg/m(2) every 21 days and erlotinib 75 mg/day), two of six patients experienced DLTs. The study was amended to enroll to "intermittent erlotinib" dosing: vinflunine day 1 and erlotinib days 2-15 of a 21 day cycle. Two of seven experienced DLTs and the study was terminated. One patient with breast cancer had a partial response; three had stable disease ≥ 6 cycles. All were treated in the continuous erlotinib group.

CONCLUSIONS

Given the marked toxicity in our patient population, the combination of vinflunine and erlotinib cannot be recommended for further study with these dosing schemas.

VEGF neutralizing antibody increases the therapeutic efficacy of vinorelbine for renal cell carcinoma

Renal cell carcinoma (RCC) is currently one of the most treatment-resistant malignancies and affects approximately three in 10,000 people. The impact of this disease produces about 31,000 new cases in the United States per year; and 12,000 people in the United States alone die from RCC annually. Although several treatment strategies have been investigated for RCC, this cancer continues to be a therapeutic challenge. For this reason, the aim of our study is to develop a more effective combinational therapy to treat advanced RCC. We examined the effect of vinorelbine on the signalling pathways of two human renal cancer cell lines (A498 and 786-O) and also examined the in vivo effect of vinorelbine treatment alone and vinorelbine in combination with the anti-VEGF antibody 2C3 on A498 and 786-O tumour growth in nude mice. Tumour angiogenesis was measured by vWF staining, and apoptosis was determined by the TUNEL assay. We observed a significant tumour growth inhibition when using a combinational therapy of anti-VEGF antibody 2C3 and vinorelbine in both A498 and 786-O tumour-bearing mice. The results suggest a breakthrough treatment for advanced RCC.

Concurrent use of vinorelbine and gefitinib induces supra-additive effect in head and neck squamous cell carcinoma cell lines

PURPOSE

Squamous cell carcinoma of the head and neck (HNSCC) remains a clinical challenge because of the high rate of locoregional disease recurrence. Standard treatment includes surgery, radiation, chemoradiation or a combination of these approaches. New therapies are needed to achieve improved survival, quality of life and organ function in these patients. A novel molecular targeted therapy incorporated into our current treatment strategies may have a significant role in the treatment of HNSCC. The aim of this study was to evaluate the sensitivity of HNSCC cell lines to vinorelbine combined with gefitinib in vitro.

METHODS

Six recently established cell lines were used: UT-SCC-9, -11, -19A, -29 and -34 (laryngeal SCC) and UT-SCC-33 (oral cavity SCC). Chemosensitivity was tested using the 96-well plate clonogenic assay. The vinorelbine concentrations used varied between 0.4 and 1.0 nM and the gefitinib concentrations varied between 0.05 and 1.6 muM. Survival data were fitted to the LQ model, and the area under the curve (AUC) value was obtained with numerical integration. The type of interaction was determined by comparing the AUC ratio of the two drugs to the survival fraction (SF) of gefitinib alone.

RESULTS

In the current study the combination of vinorelbine and gefitinib had a clear supra-additive or additive cytotoxic effect on the HNSCC cell lines.

CONCLUSIONS

This finding is encouraging as a proof of the possible benefit of combing an EGFR targeting compound with a cell cycle specific drug and warrants further studies of available combinations in vitro.

Developments in cytotoxic chemotherapy: advances in treatment utilising vinorelbine

Vinorelbine is a third generation vinca alkaloid which has been in clinical development for 15 years. Recent exploration of its pre-clinical activity has revealed unexpected evidence of potential synergy with taxane compounds and early clinical results support the suggestion of enhanced efficacy particularly in breast cancer. The initial studies establishing the clinical activity of vinorelbine in breast cancer and non-small cell lung cancer have been extended to encompass a thorough evaluation of its contribution to combination chemotherapy for these disorders. In the treatment of breast cancer useful activity has been established for vinorelbine in combination with anthracyclines, anthracenediones, antimetabolites and the taxanes; additive toxicity is not a limiting factor. The activity of vinorelbine in the treatment of non-small cell lung cancer is significantly extended by incorporation into schedules utilising cisplatin and other agents. Vinorelbine has also demonstrated useful activity in the treatment of a wide range of other malignancies including prostatic carcinoma, multiple myeloma, cancer of the ovary, cervix and head and neck and malignant lymphomas.

Effect of alpha-difluoromethyl-ornithine on the expression and function of the epidermal growth factor receptor in human breast epithelial cells in culture

We have previously shown that ornithine decarboxylase (ODC) overexpression enhances the transforming effects of HER-2neu and epidermal growth factor (EGF) in normal MCF-10A human breast epithelial cells. Our data suggest that such potentiation may be mediated by activation of the mitogen-activated protein kinase (MAPK) pathway and, possibly, STAT signalling. To further explore the interaction between the polyamine pathway and EGF/HER-2neu signalling in this system, we inhibited endogenous ODC activity with alpha-difluoromethylornithine (DFMO) and assessed the effects of this blockade on the expression of EGF receptors (EGFR) and HER-2neu as well as activation of downstream EGF target genes. We found that DFMO administration to MCF-10A cells increased EGF-R mRNA and protein levels in a dose-response fashion, while HER-2neu expression was not affected. The effect of DFMO was mediated through polyamine depletion since it could be reversed by exogenous putrescine administration. Our results also indicated that the increase in EGFR induced by DFMO was not a non-specific consequence of inhibition of cell proliferation. The upregulated EGFRs were functional since they could be phosphorylated by EGF and they were able to promote phosphorylation of downstream signalling molecules including ERK, STAT-3, and STAT-5. We propose that physiologic levels of ODC activity may be critical for regulation of a yet undefined signalling pathway, whose blockade by DFMO leads to a compensatory increase in functional EGFR.