ESTRO 36 Abstract Book

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S539 ESTRO 36 2017
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Y.M. Liu1, Y.J. Chen2, Y.K. Liu3, T.H. Tsai4
1 Taipei Veteran General Hospital, Div. of Radiation
Oncology- Dept. of Oncology, Taipei, Taiwan
2 MacKay Memorial Hospital, Department of Radiation
Oncology, New Taipei City, Taiwan
3 Chang Gung University, Department of Chemical and
Material Engineering, Taoyuan City, Taiwan
4 National Yang Ming University, Institute of Traditional
Medicine, Taipei, Taiwan
Purpose or Objective
This study investigated the adjunctive effects of Antrodia
cinnamomea mycelial fermentation broth (AC-MFB), a
Taiwanese medicinal fungus, in enhancing the
radiosensitivity of esophageal cancer cells. in vitro and in
vivo.
Material and Methods
Materials: Antrodia cinnamomea mycelial fermentation
broth, Human CE81T/VGH squamous and BE3
adenocarcinoma esophageal cancer cells, BALB/c mice.
Method: MTT assay, colony formation assay, DNA
histogram study, γ-H2AX immunofluorescence assay,
Western blotting assay, BALB/c mice animal model study.
Results
A colony formation assay showed that pretreatment with
AC -MFB decreased the survival of irradiated esophageal
cancer cells, with a maximum sensitizer enhancement
ratio of 1.91 and 37% survival. A DNA histogram study
showed that AC -MFB pretreatment enhanced cell cycle
arrest at the G2/M phase, the most radiosensitive phase.
An immunofluorescence assay and a Western blotting
assay showed that AC-MFB delayed the abrogation of γ-
H2AX, upregulated p21 expression, and attenuated the
radiation-induced phosphorylation of ataxia
telangiectasia-mutated kinase and checkpoint kinase 2. An
in vivo validation study showed that AC-MFB treatment
tended to have a synergistic effect with radiation on the
tumor growth delay of CE81T/VGH cells in BALB/c mice.
Conclusion
These data suggest that this edible fungus product could
enhance the effect of radiotherapy against esophageal
cancer.
PO-0984 Checkpoint HLA-G or its ligands ILT2/ILT4
changes radiosensitivity of renal carcinoma cell lines
C. Hennequin1, M. Daouya1, D. Tronik-Le Roux1, J.
LeMaoult 1, N. Rouas-Freiss1, F. Desgrandchamps1, E.
Carosella 1
1 Hôpital Saint-Louis, Research in Immuno-hematology,
Paris, France
Purpose or Objective
HLA-G is an immune checkpoint physiologically implicated
in maternal-foetal tolerance. It is also neoexpressed in
many cancers and particularly in more than 50% of renal
cancers. Stereotactic radiotherapy efficiency is at least in
part mediated by the immune system, and could be
modulated by the presence of immune checkpoints; for
example the use of antibodies directed against PD1/PDL1
increased radiotherapy efficiency. We investigated the
impact of expression of HLA-G or its ligands (ILT2/ILT4) on
radiotherapy efficiency at the cellular level on renal
carcinoma cell lines (RCCL).
Material and Methods
The effect of ionizing radiations (IR: 8 Gy) on the
expression of HLA-G, ILT2 and ILT4 was evaluated on RCCL
expressing or not HLA-G, ILT2 or ILT4. The impact of HLA-
G, ILT or ILT4 expression on radiosensitivity was evaluated
by clonogenic assays on transduced RCCL or controls. In
order to explain the results obtained, the following
mechanisms were investigated by cytofluorimetry: 1/
quantification of double-strand breaks (H2AX) 2/
apoptosis (Annexin V and propidium iodin PI) 3/ Cell cycle
modifications (PI)
Results
Our results showed that IR on RCCL not expressing HLA-G,
ILT2 or ILT4 did not induce these molecules. However, in
constitutively expressing HLA-G or ILT4 RCCL, IR
decreased significantly HLA-G and ILT4 expression.
Furthermore, we found that HLA-G, ILT2 and ILT4
transduction increased radioresistance. This effect was
partially aborted by the use of antibodies directed against
these molecules. Mechanisms of radio resistance are under
investigations and will be presented at the meeting.
Conclusion
Ionizing radiation decreases the expression of HLA-G or its
receptors in RCCL constitutively expressing these
molecules. HLA-G and its ligands increase radioresistance.
This finding could have some clinical implications for
stereotactic radiotherapy of renal cancer or its
metastasis.
PO-0985 Tumor metabolic changes after neoadjuvant
radiotherapy: consequences for surgery-related
metastases
N. Leroi1, F. Lallemand2, J. Leenders3, S. Blacher4, P. De
Tullio3, P. Coucke5, A. Noel 4, P. Martinive1
1C.H.U. Liège - Université de Liège, Radiotherapy Dept-
Laboratoire de Biologie des Tumeurs et du
Développement, Liège, Belgium
2C.H.U. Liège - Université de Liège, Radiotherapy Dept-
Research center of Cyclotron, Liège, Belgium
3Université de Liège, CIRM- Chimie Pharmaceutique,
Liège, Belgium
4Université de Liège, Laboratoire de Biologie des
Tumeurs et du Développement, Liège, Belgium
5C.H.U. Liège - Université de Liège, Radiotherapy Dept.,
Liège, Belgium
Purpose or Objective
Neoadjuvant radiotherapy (NeoRT) aims at improving
tumor local control and patient overall survival. In the
case of locally advanced rectal cancer, NeoRT increases
significantly local control compared to surgery alone, but
patient overall survival is not improved. Currently,
predicting tumor response and recurrences represent a
major challenge for personalized medicine. Previously, we
developed a pre-clinical model of NeoRT and showed that
the timing of surgery and NeoRT schedules both influenced
metastasis burden (Leroi et al., Oncotarget, 2015). Based
on this model, we study the impact of RT schedule on the
primary tumor metabolome at the time of surgery to
predict local recurrence and metastatic profile.
Material and Methods
We locally irradiated primary tumors (MDA-MB231 cells
and 4T1 cells), subcutaneously implanted to SCID and
BalbC mice, with two NeoRT schedules (5x2Gy and 2x5Gy).
We surgically removed tumors 4 or 11 days after the end
of RT and kept the mice alive for the metastatic growth.
Non-irradiated control tumors were also surgically
collected at the same time. For metabolomic study, tumor
samples were homogenized in deuterated phosphate
buffer and supplemented with maleic acid and TMSP
before Nuclear Magnetic Resonance (NMR) analyses. Data
were analyzed with powerful statistical tool (supervised
and multivariate analyses).
Results
Irradiated 4T1 and MDA-MB231 tumors displayed different
metabolic profile than non-irradiated tumors, especially 4
days after the end of RT for 4T1 tumors and 11 days after
NeoRT for MDA-MB231 tumors. Moreover, we observed a
decrease in some metabolite levels (i.e. glutamate,
taurine, glycine, myoinositol) in tumors following both
NeoRT schedules. We also noticed an increase in general
lipid signals in irradiated MDA-MB231 tumors. This was not
related to adipocyte infiltration, as we observed, by
immunostaining, decreased infiltration of perilipin and
FABP4+ cells in these tumors following NeoRT. Preliminary
results with OPLS-DA analyses showed discrimination of
primary tumor metabolome according to the propensity to