Akademik Veri Yönetim Sistemi
the European Association for Cancer Research (EACR), Turin, İtalya, 12 - 15 Temmuz 2023, cilt.17, sa.706, ss.158
EACR23-0706
EFFECT OF TRANSMEMBRANE EMP24
DOMAIN PROTEIN TMED9 IN MULTIPLE
MYELOMA PROLIFERATION
Ş. Punar1
, B. Salman Yaylaz1
, S. Sırma Ekmekci1
, N. Abacı1
1
Aziz Sancar Institute of Experimental Medicine- Institute o
f Graduate Studies in Health Sciences- Istanbul University,
Genetics, Istanbul, Turkiye
Introduction
Multiple myeloma (MM) is a malignancy of terminally
differentiated plasma cells. MM is one of the most
common cancers among hematological malignancies. It is
characterized by the overproduction and accumulation of
non-functional immunoglobulins or immunoglobulin
chains in the plasma cells. The product of the TMED9 gene
is the carrier protein expressed on the endoplasmic
reticulum (ER) membrane. It plays a role in the transport of
proteins. As we previously found the high RPKM value
of TMED9 gene in MM patients with the transcriptome
study, we hypothesized TMED9 may have a role in the
pathogenesis of MM. Therefore, in this study, we aimed to
investigate the function of the TMED9 gene in MM cell
lines.
Material and Methods
TMED9 gene expression was suppressed by siRNA with
the electroporation method in U266 and RPMI8226 cell
lines. TMED9 gene was overexpressed by using
expression vector in both cell lines. After gene suppression
and overexpression, the expression levels were determined
by qPCR. The change in the protein level of TMED9 was
shown by western blot analysis. Cells were stained with
three fluorescent dyes which are Apopxin green,7-AAD and CytoCalcein Violet 450. Cells were visualized under
confocal microscopy to determine apoptosis in the control
and treated groups. The number of apoptotic and viable
cells were counted with the ImageJ program. The cell
proliferation was determined with the MTT assay.
Results and Discussions
In siRNA-treated groups, the suppression of TMED9 was
calculated by ΔΔCT method at 24 and 48 hours compared
to control groups. Likewise, the overexpression level in the
vector-treated cells was calculated by ΔΔCT method
compared to control groups. Suppression and
overexpression of TMED9 were demonstrated at the
protein level by Western Blot. As a result of the
suppression of siRNA-mediated gene expression, it was
shown, the rate of apoptotic cells increased compared to
the control group. MTT results revealed that cell
proliferation decreased siRNA-treated group compared to
the control group. On the other
hand, TMED9 overexpression showed increased cell
viability and proliferation compared to the control group.
Conclusion
In this study, we found that suppression of TMED9 gene
expression decreased the viability of MM cells and
triggered apoptosis. Our results are promising in MM,
as TMED9 has been shown to be associated with poor
prognosis in a different types of cancers. It is also the first
functional study with the TMED9 gene in U266 and RPMI8266 cells.