Journal Thoracic Oncology

Abstracts Journal of Thoracic Oncology • Volume 12 Issue S1 January 2017
Keywords: prognostic prediction, NSCLC, chemotherapy, metabolomics
PUB147 KRAS MUTANTS REGULATED PD-L1 EXPRESSION THROUGH
NF-ƘB AND HIF-1Α PATHWAYS IN NON-SMALL CELL LUNG CANCER
CELLS
Rong Guo, Jie Wang, Hua Bai
Cancer Hospital Chinese Academy of Medical Sciences, Beijing/China
Background: KRAS is one key driving gene for tumorigenesis of lung cancer
and plays an important role in EGFR-TKIs resistance. To investigate the
molecular mechanism of the expression regulation of PD-L1 by mutant KRAS
gene in NSCLC cells, we had pursued researches as described below. Methods:
The expression of PD-L1 and downstream signaling molecules of KRAS gene,
including p-AKT, p-ERK, p-IƘB and HIF-1α, in 13 NSCLC cells were examined by
Western blot. Additionally, two NSCLC cells, H292 and H661, were transfected
with various KRAS mutants and treated with MEK/ERK inhibitor U0126, PI3K/
AKT inhibitor LY294002, and NF-ƘB inhibitor BAY117082, respectively, and
further examination of the expression of PD-L1 and key signaling molecules
of KRAS pathway by Western blot was carried out. Results: The significantly
positive correlation between expression levels of PD-L1 protein and p-IƘB as
well as HIF-1α proteins in 13 NSCLC cells. Furthermore, MEK/ERK and PI3K/
AKT/mTOR all participated in the process of up-regulated PD-L1 expression by
KRAS mutants in both H292 and H661 cells. Notably, the variation tendency of
p-IƘB expression and especially HIF-1α showed strong consistency with PD-L1
in both H292 and H661 cells treated with KRAS mutants and the three kinds
of inhibitor.Conclusion: Our findings revealed that KRAS mutants regulated
PD-L1 expression through NF-ƘB and HIF-1α pathways in NSCLC cells, and
suggested the correlation between EGFR-TKIs resistance and immune
escape as well as significance of combined treatment of target therapy and
immunotherapy in NSCLC.
PUB149 CROTON TIGLIUM EXTRACT INDUCES THE APOPTOSIS IN
HUMAN LUNG CANCER A549 CELLS
Changyou Li, Xiao Wu, Rongli Sun, Peng Zhao, Fengjuan Liu, Chunling Zhang
Qingdao Central Hospital, Qingdao/China
Background: Croton, a large genus of Euphorbiaceae, is widely distributed in
tropical regions of South-East Asia and China. Many researchers previously
reported the pharmacological and physiological actions of Croton species on
anti-inflammatory, anticonvulsant and wound healing properties .Mature
Croton tiglium contains large amounts of natural medical components, in
which croton alkaloid, flavonoids and diterpenes are anticancer agents.
The study on application of Croton in lung cancer is lacking. In this study,
we investigated the regulating effects of Croton tiglium extract on A549
cell proliferation and apoptosis. Methods: Preparation of Croton tiglium
seed extract. A549 human lung cancer cell cultures Cell viability assay Flow
cytometric analysis of apoptosis Results: The MTT assay showed that Croton
tiglium extract could exert a significant inhibitory effect on the proliferation
of A549 cells. (Figure 1, P