Background

The ‘Methodology for the Development of Innovative Cancer Therapies’ (MDICT) task force was originally established in 2006 to provide practical guidance on the development of anticancer targeted agents. The task force published a number of recommendations. [1] [2] [3] [4] Although originally focused on targeted agents, for 2018, it was decided to convene the task force to examine issues in the development of immune based therapies. [1] Booth CM, Calvert AH, Giaccone G, Lobbezoo MW, Seymour LK, Eisenhauer EA. Endpoints and other considerations in phase I studies of targeted anticancer therapy: Recommendations from the task force on Methodology for the Development of Innovative Cancer Therapies (MDICT). EJC 2008;44(1):19–24. [2] Booth CM, Calvert AH, Giaccone G, Lobbezoo MW, Eisenhauer EA, Seymour LK. Design and conduct of phase II studies of targeted anticancer therapy: Recommendations from the task force on methodology for the development of innovative cancer therapies (MDICT). EJC 2008;44:125–9. [3] Goodwin R, Giaccone G, Calvert H, Lobbezoo M, Eisenhauer EA. Targeted agents: How to select the winners in preclinical and early clinical studies? Eur J Cancer 2012;48:2170–8. [4] Seymour LK, Calvert AH, Lobbezoo MW, Eisenhauer EA, Giaccone G. Design and conduct of early clinical studies of two or more targeted anticancer therapies: Recommendations from the task force on Methodology for the Development of Innovative Cancer Therapies.

Methods

Participants included experts from academic centres as well as from industry and regulatory authorities. The mandate of the meeting was to review current knowledge and discuss and make recommendations regarding the design and conduct of early clinical studies of combinations of immune based anticancer agents.

Results

Response patterns and current criteria were reviewed. Critical issues were identified regarding capacity, trial design, optimal endpoints, data sharing and the publication of results. A structured discussion was conducted to allow recommendations on data needed to justify a proposed combination, optimal endpoints and design.

Conclusions

Clinical trial identification

Not applicable

Conclusions

At the end of the MDICT meeting, agreed recommendations were summarized and then presented for feedback to the audience attending TAT2018.

Legal entity responsible for the study

Queens University

Disclosure

J. Tabernero: Has served on advisory boards for Bayer, Boehringer Ingelheim, Genentech/Roche, Lilly, MSD, Merck Serono, Novartis, Roche, Sanofi, Symphogen and Taiho. All other authors have declared no conflicts of interest.

Funding

Has not received any funding

Background

Estrogen drives cellular proliferation and survival in estrogen receptor-positive (ER+) breast cancer. Exposure to endogenous or exogenous estrogen is a well-established cause of breast cancer and target of endocrine therapies such as antiestrogens and aromatase inhibitors. However, their efficacy is limited by intrinsic or acquired endocrine resistance which remains a significant clinical challenge. A third of patients given the antiestrogen therapy tamoxifen for 5 years develop recurrence and metastasis within 15 years. Gene expression studies of endocrine resistance suggest the dysregulation of epigenetic enzymes has an important role in survival signaling and cellular proliferation in acquired endocrine resistance. The development of epigenetic modifier inhibitors offers the promise of dynamically targeting mediators of acquired resistance that may be exploited as biomarkers and therapeutic targets to improve patient prognosis.

Methods

The in vitro work was performed using endocrine-resistant and endocrine-sensitive breast cancer cell lines. Proliferation was measured by changes in cellular confluency over time and viability determined by MTT assay. In vivo studies were investigated using a mouse xenograft model.

Results

In this study, we identified a histone methyltransferase that is regulated epigenetically and when targeted in combination with endocrine therapy it significantly reduces the proliferation and the viability of resistant cells in vitro, and it leads to a significant reduction in tumour growth in a mouse xenograft model.

Conclusions

Tamoxifen and histone methyltransferase inhibitor reduce proliferation and viability of tamoxifen-resistant and sensitive breast cancer cell lines. Histone methyltransferase inhibitor re-sensitises resistant breast cancer and causes tumour regression in a mouse xenograft model. Therefore, tamoxifen-resistant ER+ breast cancer can be re-sensitised by epigenetic therapy.

Legal entity responsible for the study

QIMR Berghofer

Funding

QIMR Berghofer

Disclosure

All authors have declared no conflicts of interest.

Background

Prostate cancer (PC) is one of the leading cause of cancer related deaths in men. PC progression and recurrence following initial treatments possesses mortality threat amongst these patients. Cell cycle re-entry of quiescent cancer cells has been suggested for cancer progression and recurrence. The slow progression of PC allows a window of opportunity for intervention through diet. An inverse association of flavonoids intake and PC development has been demonstrated in epidemiological studies. We hypothesized that citrus peel that is rich in various bioactive compounds including flavonoids may impede cell cycle re-entry by quiescent PC cells.

Methods

Actively proliferating prostate cancer cells (PC-3) were induced into quiescence by contact-inhibition. The cells were released from quiescence by diluting the cells to lower density in the presence of citrus peel extract.

Results

Our study revealed that the experimental quiescent PC-3 progressed from G0/G1 to S phase following release from quiescence. Compared with the 20% reduction of G0/G1 cells upon cell cycle re-entry, only 3% reduction of G0/G1 cells was noted in the presence of citrus peel extract at 48 hours. In parallel, there was a significant decreased in DNA synthesis in PC-3 cells treated with the extract compared to the control as evaluated by EdU incorporation assay. The cell death was not observed in PC-3 cells when tested using Annexin V-FITC assay. Moreover, the compound responsible for inhibiting the cell cycle re-entry was isolated and identified using chromatographic method. Relevant analysis to validate the compound activity is underway.

Conclusions

This study suggests that citrus peel extract is able to inhibit the cell cycle re-entry of PC cells. The recovery and utilization of bioactive compounds from orange peel waste will open an avenue for developing affordable fortifying food products with potential to reduce the risk of cancer recurrence.

Legal entity responsible for the study

The University of Sydney

Funding

The University of Sydney and LangTech International Pty Ltd.

Disclosure

All authors have declared no conflicts of interest.

Background

Androgen receptor (AR) is playing an important role in the progression of a subset of TNBC. We evaluated the impact of ERβ expression along with anti-AR drugs in AR-positive TNBC.

Methods

We used MDA-MB 453 human cell line, representative for AR⁺/ERβ^- molecular profile. pEGFP-C1-ERβ plasmid was transfected into MDA-MB 453 cells. Cell proliferation, metastatic potential and apoptosis were examined using MTT assay, scratch assay and Annexin V-FITC assay, respectively. Protein levels of PI3K/AKT molecules were assessed using Western blot. All assays were also conducted in the presence of anti-androgens; bicalutamide and enzalutamide. The localization of AR and ERβ was detected by immunofluorescence. In order to test if a physical association (ERβ/AR) occurs, proximity ligation assay (PLA), which enables the visualization of interacting proteins in fixed cells and tissues, was performed.

Results

MDA- MD 453/ERβ cells exhibited reduced cell proliferation (19%±0.06), lower metastatic potential (50%±2.4) and increased late apoptosis (12%) compared to MDA-MB 453 mock cells. ERβ suppressed PI3K/AKT pathway through PTEN and inhibited the activation and nuclear translocation of AR. Also, ERβ significantly impeded AR from forming homodimers, reversing the aggravating role of AR. It was also shown that enzalutamide was superior to bicalutamide regarding cell proliferation, metastatic potential and stimulated apoptosis. In addition, using PLA assay, we demonstrated a strong physical interaction between ERβ and AR in MDA- MD 453/ERβ cells. The administration of enzalutamide enhanced the formation of ERβ/AR heterodimers reducing further proliferation (54%±0.003) and metastatic ability (81%±4.5) and inducing late apoptosis (21%). Lastly, employing PLA assay in TBNC human paraffin embedded tissues, we found a strong interaction between ERβ and AR, recapitulating the in vitro results.

Conclusions

Our results suggest that ERβ has oncosuppressive potential in AR-positive TBNC development and provide mechanistic insights regarding its’ predictive role for the efficacy of anti-AR agents in this TNBC group.

Legal entity responsible for the study

Michalis V. Karamouzis

Funding

Astellas Pharma Europe Ltd.

Disclosure

All authors have declared no conflicts of interest.

Background

The Hedgehog (Hh) signaling pathway is an evolutionarily conserved pathway of signal transmission which plays a significant role in the normal embryonic development of invertebrates and vertebrates. In the adult organism, Hh signaling pathway is mostly inactive or poorly active while its hyperactivation is associated with carcinogenesis. Binding of the Hh ligands, Sonic Hedgehog (SHh), Indian Hedgehog (IHh) and Desert Hedgehog (DHh) along with PTCH protein activates Hh signaling resulting in increased activity of the GLI transcription factors that activate targeted genes. The status of Hh pathway components in serous ovarian carcinomas is poorly understood.

Methods

Formalin-fixed paraffin-embedded samples of 11 low-grade (LGSC), 40 high-grade serous ovarian carcinomas (HGSC) and 7 normal/benign ovarian tissues (controls) were used for this study. SHh and IHh protein expression was explored using immunohistochemistry. DNA methylation pattern of SHh and IHh gene was analyzed by methylation-specific PCR (MSP).

Results

SHh and IHh expression was significantly higher in both LGSC (p < 0.001 and p = 0.011, respectively) and HGSC (p < 0.001 and p = 0.003, respectively) compared with normal/benign ovarian tissues. There was no statistically significant difference in SHh and IHh protein expression between LGSC and HGSC. SHh and IHh DNA methylation was observed in HGSC [(2/40, 5%) and (1/40, 2.5%), respectively]. In all normal ovarian tissues no methylation was detected.

Conclusions

A significant proportion of serous ovarian carcinomas exhibits increased SHh and IHh protein expression, which indicates that these Hedgehog signaling pathway components may be actively involved in pathogenesis of serous ovarian carcinomas. Therefore, SHh and IHh might serve as potential therapeutic targets for serous ovarian carcinomas. Low methylation levels of the respective genes in HGSC and absence of methylation in LGSC and normal ovarian tissues indicate alternative mechanisms of SHh and IHh activation. Further clinical studies should confirm the clinical and therapeutic relevance of the observed Hh alterations.

Legal entity responsible for the study

School of Medicine, University of Zagreb

Funding

School of Medicine, University of Zagreb

Disclosure

All authors have declared no conflicts of interest.

Background

Gene expression profiles in spheroid cultivated cells are more similar to natural tumors, than profiles of the same cells in monolayer culture. Tumor spheroids are heterogeneous cellular aggregates that, when greater than 500 μm diameter, are frequently characterized by hypoxic regions and necrotic centers. Architecture of three-dimensionally (3D) propagated cells is very similar to avascular tumor areas. The gradient of diffusion in cell aggregates leads to reduced proliferation rates and increased drug resistance. The purpose of the work was to conduct a comparative study between 3D and monolayer growth systems of MCF-7 cells, and prove the value of spheroid model.

Methods

As experimental model was used adhesion line of breast adenocarcinoma MCF-7. Cells in 2D and 3D culture were incubated during 5 days under conditions of starvation. The number of live cells was evaluated using MTT-colorimetric assay. Apoptotic index was assessed by flow cytometry.

Results

MCF-7 cells growth parameters differ significantly in 2D and 3D growth systems. Cells in 2D system are more sensitive to serum starvation then 3D cultures. Cell viability increases dramatically in 3D system. The level of apoptotic and necrotic cells for 2D growth in serum starvation conditions (39.2±7.3% and 33.5±2.8% respectively) were twice increased in comparison with conditions of complete culture medium (19.0±1.3% and 11.4±1.7% respectively), whereas incomplete medium have no detectible effects on 3D cultured cells. However, the 3D cells percentage in G₀/G₁ phase of the cell cycle was increased in 1.6 times in serum free conditions, whereas it was not changed in complete medium that can indicate similarity to natural tumors.

Conclusions

Therefore, the 3D growth system has been proposed as an adequate and valuable model to study tumor growth and response to therapeutic substances.

Legal entity responsible for the study

Taras Shevchenko National University of Kyiv, ESC “Institute of Biology and Medicine”

Funding

Has not received any funding

Disclosure

All authors have declared no conflicts of interest.

Background

Breast cancer is the leading cause of cancer-related deaths in women aged 45 and younger in developed countries, and although generally improving, survival rates for young women with breast cancer remain lower than for older women. The aim of the study was to evaluate the percentage and the outcome of women younger than 45 with HER2 positive disease.

Methods

Medical files of 625 women diagnosed with breast cancer between 2007-2015 were retrospectively analysed. There were 134 (21.4%) patients younger than 45 at diagnosis. In this subgroup of patients 32 were diagnosed with HER2 positive disease. The time to tumor progression of young patients with HER2 disease was compared with a matched control group of patients with HER2 disease older than 45. All patients received chemotherapy and trastuzumab. No patents received neoadjuvant trastuzumab (due to lack of reimbursement).

Results

In the group of 32 young women, median age at diagnosis was 36.5 years, stage distribution was 12.5%, IIA, 9.4% in stage IIB, 43.7% stage IIIA, 21.9% stage IIIB,12.5% stage IV. Compare to the rest of the patients, the younger was diagnosed more often with advanced and metastatic disease (p = 0.043). The incidence of HER2 positive disease was similar in our group (23.8%) compare to entire group (26.4%). Ki 67 percentage ranged between 11% and 75% (median was 35%). The median disease-free survival for young group was 65 months were for control was not reached; the 3-year and 5-year disease-free survival were 58% and 50%, respectively compare to 63% and 55% for older women. The 3-year and 5-year overall survival were 78% and 58%, respectively significantly lower than in the matched controlled group P = 0.039.

Conclusions

Our lot of patients diagnosed with HER2 positive disease aged less than 45 years was diagnosed in a much more advanced stage and had a poorer prognosis compared with HER2 positive patients older than 45 years.

Legal entity responsible for the study

N/A

Funding

Has not received any funding

Disclosure

All authors have declared no conflicts of interest.

Background

Oncogenic mutations in growth factor receptor signaling pathways are common in cancer, including in tumors that arise from or metastasize to the brain. However, most small-molecule inhibitors targeting growth factor receptors have failed to show efficacy for brain cancers, potentially due to inability to achieve sufficient drug levels in the central nervous system (CNS). Targeting tumor co-dependencies provides an alternative approach, particularly if drugs with high brain penetration can be identified.

Methods

In vitro cytotoxicity assays, mass spectoscopy, and orthotopic GBM in vivo models were used to assess cholesterol dependency and sensitivity to Liver X Receptor (LXR) activation using established GBM cell lines and patient-derived ex vivo tumor neurosphere cultures.

Results

We demonstrate that EGFR-mutant cancers, including a highly lethal form of brain cancer glioblastoma (GBM), are remarkably dependent on cholesterol for survival, rendering them sensitive to Liver X receptor (LXR) agonist-dependent cell death. We show that LXR-623, a clinically viable, highly brain-penetrant LXRα-partial/LXRβ-full agonist selectively kills GBM cells in an LXRβ- and cholesterol-dependent fashion, causing significant tumor regression and prolonged survival in mouse models.

Conclusions

Thus, a metabolic co-dependency provides a pharmacological means to kill growth factor-activated cancers in the CNS.

Legal entity responsible for the study

Ludwig Institute for Cancer Research

Funding

National Institute of Health, National Cancer Institute, F31CA186668

Disclosure

The author has declared no conflicts of interest.

Background

Glioblastoma multiforme (GBM) is the most aggressive form of malignant primary brain tumors in adults with a survival of only 12-15 months. We previously showed that ZR2002, a chimeric aminoquinazoline designed to possess mixed EGFR tyrosine kinase (TK) inhibitory and DNA targeting properties exhibits potent activity against GBM established cell lines and brain tumor stem cells in vitro.

Methods

We analyzed the in vivo plasma and brain pharmacokinetics (PK) of ZR2002 using various doses and via different routes in CD-1 mice. Mice were sacrificed at 15 min, 30 min, 1 hr, 3 hr, 8 hr, 24 hr after drug administration to quantify the amount of ZR2002 in plasma and brain homogenate of mice using RB10 as an internal standard and HPLC-MS/MS method. For the in vivo efficacy of ZR2002, U87/EGFRvIII cells stably transduced to express luciferase were injected into the right corpus striatum of the brains of 4–6 week-old Nu/Nu nude mice. We monitored tumor growth by luciferase bioluminescence imaging and mice were randomized to receive ZR2002 or vehicle control.

Results

Doses at 12.5 mg/kg IV, and 50 mg/kg PO ZR2002 did not cause any observable toxicity up to 24 h or in a subsequent experiment testing higher doses up to 150mg/kg PO compared to vehicle control with longer time follow-up over three weeks following drug administration. ZR2002 was detectable in the brain homogenate of mice at 3.58 µg/g or 2.76 µg/g for PO/50 mg/kg/3 hr (t max) or IV/12.5 mg/kg/5 min (t max), respectively. Our efficacy study showed that ZR2002 significantly improved the survival of intracranial U87/EGFRvIII tumor-bearing mice, compared to the control group (p value <0.0005).

Conclusions

We conclude that ZR2002 is able to cross the blood brain barrier and exhibits anti-tumor activity in U87/EGFRvIII orthotopic tumor mouse model, suggesting that this combi-molecule should be further developed in pre-clinical studies as a new treatment strategy in GBM.

Legal entity responsible for the study

McGill University

Funding

This research is partly funded by the Canadian Cancer Society grant #70217 (PK study) and Cancer Research Society grant#22716 (Efficacy Study)

Disclosure

All authors have declared no conflicts of interest.