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Gemcitabine Sensitivity on
Podocalyxin Knockdown Pancreatic Cell Line SW1990
by
Yuan-Hsiao Billy Huang
A thesis submitted to Johns Hopkins University in conformity with the requirements
for the degree of Master of Chemical Biomolecular Engineering
Baltimore, Maryland
November, 2014
© 2014 Yuan-Hsiao Billy Huang
All Rights Reserved
ii
Abstract
In this study, we tested cell survival following treatments of Gemcitabine (GE)
in scrambled control and Podocalyxin (PODXL) knockdown pancreatic cancer cell
line SW1990. After testing several major chemotherapeutic drugs with MTT cell
survival assay, GE, brand name Gemzar, was shown to have a much higher cytotoxic
effect on PODXL knockdown cells than control SW1990 pancreatic cancer cells.
Upon observation, we suggested that knocking down PODXL could potentially
reduce the resistance and/or increase the sensitivity of SW1990 to GE. With this
hypothesis, we proceeded to test the expression of NF-κB targeted genes, which are
indicator of cell survival mostly related to cell apoptosis, in both scrambled control
and PODXL knockdown cells with and without GE treatments. The seven specific
genes analyzed were cyclin D1, c-myc, bcl-2, bcl-xL, c-IAP1, cox-2 and MMP9.
Apoptosis-related gene expressions were analyzed by reverse transcription-
polymerase chain reaction (rt-PCR). Our results showed that five out of seven of the
anti apoptotic genes were down regulated in PODXL knockdown and two out of
seven of the anti apoptotic genes were significantly down regulated in PODXL
knockdown following GE treatment. Combined data supports our hypothesis that
PODXL knockdown cells are more sensitive to GE as a result of apoptosis induction.
ACKNOWLEDGEMENTS
The excellent technical support by Dr. Jack Shih-Hsun Chen is greatly acknowledged.
iii
Table of Content
Introduction ............................................................................................................................... 1
Experimental Methods ............................................................................................................ 7
Result ............................................................................................................................................ 9
Discussion ................................................................................................................................ 15
Reference .................................................................................................................................. 19
Curriculum Vitae .................................................................................................................... 22
1
INTRODUCTION
Pancreatic cancer is one of the most deadly diseases in the world. Due to
its resistance to most cytotoxic drugs, pancreatic cancer patients’ five-year
relative survival rate is as low as 3 percent. [1] Such low percentage could be the
result of suboptimal drug delivery, poor drug efficacy, insufficient cellular uptake,
and chemotherapeutic resistance. In this study, a surprising increase in cell
death was observed following treatment of GE in pancreatic cancer cell line
SW1990 upon the knockdown of a transmembrane protein, PODXL.
PODXL is a transmembrane protein that is expressed in many types of
human cells such as platelets and vascular endothelial cells. [2] First discovered
in kidney, PODXL’s main function is the keep the unitary filtration barrier open.
[3] It is upregulated in numerous types of cancers such as breast, colon, and
pancreatic cancers. [4] PODXL has been identified as a functional E- and L-
selectin ligand expressed by metastatic pancreatic cancer. [5] Data also shown
that metastatic pancreatic cancer cells overexpress PODXL compared with
nonmalignant pancreatic epithelial cells. [5] Yet, PODXL’s connection with GE
resistance is still largely unexplored.
GE is a nucleoside analogue used as an anti-neoplastic drug. It causes
apoptosis by replacing cytidine during DNA replication or by binding to
ribonucleotide reductase (RNR). [6] Once transported through cellular
2
membrane, GE is phosphorylated into its active diphosphate and triphosphate
form, which competes with the natural deoxycytidine-triphosphate analog for
incorporation in DNA and RNA. This metabolism inhibits cytidine triphosphate
synthase and terminates DNA synthesis. GE is currently the first-line agent for
advanced pancreatic treatment. However, low protein binding of less than 10%
as revealed by pharmacokinetic data low response rate of 20% indicate the need
for improvement in overall GE performance. [7]
GE response in pancreatic cancer involves many intracellular pathways.
In this study we specifically focused on the end terminus of the
Phosphatidylinositol-3 kinase/AKT/NF-κB axis, the NF-κB targeted genes.
Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) is anti-
apoptotic transcription factor that promotes cancer growth. In short, GE exerts
its cytotoxic effect in pancreatic cancer cells in vitro and in vivo by inhibiting NF-
κB and its targeted genes cyclin D1, c-myc, bcl-2, bcl-xL, c-IAP1, cox-2 and MMP-9,
which promotes cell death. [8,9,10]
In this work we focused on the expression of seven targeted genes of
control and PODXL knockdown cells before and after treatment with 10 μM GE
for 72 hours. Each of the seven genes listed influence the survival of pancreatic
cancer cells, but the knowledge of the seven NF-κB targeted genes is not yet fully
understood and their complete functions are still under investigation. Since this
work mainly focuses on the NF-κB gene expressions, we provide a
3
comprehensive review of each gene with special regards to how they affect
apoptosis.
NF-ΚB: cyclin D1, c-myc, bcl-2, bcl-xL, c-IAP1, cox-2 and MMP-9
Cyclin D1 is a protein kinase that regulates cell cycle. It is overexpressed
gene in breast carcinoma. [11] Overexpression of cyclin D1 promotes growth in
pancreatic tumor cancer cells and cyclin D1-overexpressing cells exhibit
significantly reduced chemosensitivity to cisplatin. [12] This suggests that
overexpression of cyclin D1 could cause chemoresistance in pancreatic cancer
due to its roles in promoting cell proliferation and inhibiting drug-induced
apoptosis.
C-myc is another regulatory gene that regulates cell proliferation. In many
cancers, mutated version of c-myc causes c-myc to be persistently expressed,
leading to disrupted expression of many other downstream genes associated
with cell proliferation. [13] C-myc is overexpressed in pancreatic cancers and
renders them resistance to cisplatin. [14] Overexpressing c-myc could interfere
with the process of apoptosis and leads to unregulated cell growth.
Bcl-2 is an anti-apoptotic protein in pancreatic cancer and many other
tumors. [15] Bcl-2 is an integral membrane protein located on the outer
4
membrane of mitochondria that prevents apoptosis by blocking the release of
cytochrome c, an initiation factor of apoptosis [16] In a multiple myeloma
chemotherapy study, bcl-2 overexpression is associated to resistance to
paclitaxel, but not GE. [17] Paclitaxel induces cell arrest at G2/M phase whereas
GE induces cell arrest at S phase of the cell cycle. In this particular study,
paclitaxel induced a down regulation of bcl-2 whereas treatment with GE did not
affect bcl-2 expression. This suggests that bcl-2 might be irrelevant to GE
resistance in pancreatic cancer. Although bcl-2 might not be directly influenced
by GE treatment, its antiapoptotic character is noteworthy.
B-cell lymphoma-extra large (bcl-xL) is also a member of the bcl-2 family.
Like bcl-2, bcl-xL is a transmembrane protein in the mitochondria, which is also a
pro-survival protein that prevents the release of mitochondrial substances, such
as many proteases, and eventually prevents apoptosis. bcl-xL protein level is a
very useful tool to determine the apoptotic index. In a recent study analyzing the
expression of Bcl-2, Bcl-xL, and Bax in pancreatic ductal carcinoma and their
correlation to the extent of apoptosis, an upregulation of all the apoptotic
regulatory molecules, especially bcl-xL, was observed. (The apoptotic index was
determined by terminal deoxynucleotidyl transferase-mediated nick end
labeling (TUNEL) essay) [18] Therefore bcl-xL expression could be used as an
indicator of relative apoptotic rate in this GE study.
5
Baculoviral IAP repeat-containing protein 2 (c-IAP1), like bcl-2 and bcl-xL,
is a prosurvival protein that inhibits apoptosis by interfering with the activation
of caspases, which are a family of cysteine proteases that play essential role in
apoptosis. In both neoplastic and non-neoplastic pancreatic cancer cells,
overexpression of c-IAP1 is observed in the early stage of cancer progression. [19]
In particular, c-IAP1 plays a role in the inhibition of TNF-alpha-induced apoptosis
by inducing NF-κB. [19] Therefore its expression is expected to decrease in
PODXL knockdown cells since they became more sensitive to GE.
Cyclooxygenase-2 (cox-2) is an enzyme responsible for inflammation and
pain, which converts arachidonic acid to prostaglandin during inflammation.
Prostaglandin E2, a prostaglandin derivative, can stimulate cancer progression.
[20] It is upregulated in pancreatic ductal adenocarcinomas (PDAC). [21]
However, the mechanism of how cox-2 promotes PDAC is unclear. Some has
suggested that deregulation of the cox-2/PGE2 pathway appears to affect
colorectal tumorgenesis by promoting tumor maintenance and progression, and
encouraging metastatic spread. [22] In relation to apoptosis, inhibition of cox-2
in a hepatocellular carcinoma study induces apoptosis signaling, activation of
caspases, and apoptosis originating from mitochondria. [23]
At last, matrix metallopeptidase 9 (MMP-9) is a protease that is involved
in the breakdown of the extracellular matrix in normal physiological processes
and plays a major role in pancreatic cancer growth and metastasis. [24] MMP-9 is
6
more associated with cancer cell invasiveness rather than apoptosis. However,
MMP-9 causes the recruitment of pericytes and pericytes invasion in primary
tumor development during the degradation of extracellular matrix. [25]
Pericytes induced the antiapoptotic protein Bcl-w in tumor endothelial cells both
in vivo and in vitro thereby protecting tumor cells from cytotoxic elements. [26]
Therefore, indirectly, MMP-9 may regulate apoptosis either through the
generation of extracellular matrix molecules or transactivation of cell surface
receptors. [25] Data also suggests the anti-apoptotic roles of a numbers of MMPs
in vitro including MMP-7, MMP-9, MMP-10 and MMP-15. [27,28,29] These MMPs
could also be related to apoptosis resistance in tumor cells by assisting or
enhancing the early stages of tumor dissemination. [30,31] Therefore a decrease
in MMP-9 expression may be expected in PODXL knockdown cells against GE.
7
Table 1 summarizes the above information of each gene on apoptosis and
the predicted expression upon GE treatment to the more sensitive PODXL
knockdown pancreatic cancer cells.
NF-κB
Genes
cyclin
D1
c-myc bcl-2 bcl-xl c-IAP1 cox-2 MMP-9
Apoptotic
Effect
_ _ _ _ _ _ _*
Expected
Expression
in GE-
PODXL
Condition
TABLE 1: SUMMARY OF NF-ΚB TARGETED GENES EFFECTS ON APOPTOSIS. A NEGATIVE MARK INDICATES ANTI-
APOPTOTIC AND THE ASTERISK INDICATES INDIRECT EFFECT. THE DOWNWARD ARROW INDICATES A DOWN
REGULATION OF THE GENE EXPRESSION. GE-PODXL REFERS TO THE PODXL KNOCKDOWN CELLS TREATING
WITH GE FOR 24 HOURS.
EXPERIMENTAL METHODS
CELL CULTURE:
The pancreatic adenocarcinoma cell lines SW1990 was obtained from the
American Type Culture Collection (Manassas, VA) and Pa03C was a generous gift
from Dr. Anirban Maitra (Johns Hopkins School of Medicine, Baltimore, MD, USA).
[5] SW1990 and Pa03c-PODXL knockdown cell line was provided by Dr. Matt
Dallas. [5] SW1990 cells were cultured in DMEM supplemented with 10% FBS
and 50 μg/ml gentamicin. Cells were harvested via mild trypsinization (0.25%
trypsin/EDTA·4Na for 5 min at 37°C) and incubated at 37°C for 2 h to regenerate
surface glycoproteins. [5]
8
CELL SURVIVAL ASSAY:
SW1990/Pa03c control and PODXL knockdown cells (5,000/well) were
seeded in 96-well plates in duplicates and allowed to adhere overnight. After
overnight incubation, the cells were treated with various concentrations of GE of
0, 0.1, 1, 10, and 100 μM for 72 hours. Cell survival was measured by a standard
MTT assay.
MTT ASSAY:
Cell viability was evaluated using 3-[4,5-dimethylthiazol-2-yl]-3,5-
diphenyl tetrazolium bromide (MTT) test. After the treatment period as
indicated above, the incubation media were removed and exchanged with 100 µl
of fresh media containing MTT (0.2 mg/ml), and cells were incubated at 37°C for
3 hours. The media were removed, and formazan crystals were solubilized with
150 µl of DMSO. Absorbance at 570 nm was measured in triplicate using a
microplate reader. [32]
Reverse Transcription Polymerase Chain Reaction (rt-PCR):
Control and PODXL knockdown cells and control and PODXL knockdown
cells treated with GE for 24 hours were prepared in 6-well plates. Instead of 72
hours, we treated cells with GE for 24 hours to test gene expressions before
9
major cell death occurred. Upon 100% confluency, cells were washed with cold
PBS twice before extracting the mRNA with Trizol. Extracted mRNAs were
prepared at sample size of 5 μg in triplicate along with other necessary reagents
(RNAse, primers, etc.). The reagents are iTaqTM Universal Supermixes from Bio-
Rad. Primers’ sequences were obtained from NCBI. Primers were obtained from
Invitrogen. GAPDH was used as a reference to all genes.
RESULT
SW-PODXL KNOCK DOWN CELLS ARE 13% MORE SENSITIVE TO GEMCITABINE THAN
CONTROL CELLS
To investigate the sensitivity of human pancreatic cancer cell line
SW1990 and its PODXL knockdown to anticancer drugs, we tested
chemotherapeutic agent GE for pancreatic cancer in a dosage dependent manner.
Cells were incubated for 72 hours to a range of each agent’s concentrations going
from 0.1 to 100 μM. Among all the different conditions, PODXL knockdown cells
exhibited increased sensitive to GE compared to the control cells. Shown in
Figure 1, differences in cytotoxic effect were observed in different
concentrations of GE treatment. There is 10 to 22 percent cell death differences
in different drug concentrations. Figure 2 is the supplementary data of another
pancreatic cell line Pa03c for the generalization purpose.
10
FIGURE 1: PANCREATIC TUMOR CELLS SW 1990 SENSITIVITY TO GE. CELL SURVIVAL ASSAY WAS PERFORMED
USING MTT METHOD. CELLS WERE TREATED FOR 72 HOURS WITH INCREASING CONCENTRATION OF GE (0.1 –
100 UM) CELL VIABILITY WAS PRESENTED AS A PERCENTAGE OF UNTREATED CELL CONTROL VALUES. BLUE
DOT MARK REPRESENTS SCRAMBLE CONTROL WHILE THE TRIANGLE MARK REPRESENTS THE PODOCALYXIN
KNOCKDOWN CELL LINE.
FIGURE 2: PANCREATIC TUMOR CELLS PA03C SENSITIVITY TO GE. CONDITIONS SAME AS FIGURE 1.
0
25
50
75
100
0 0.1 1 10 100
% C
ell
Su
rviv
al
Gemcitabine (uM)
SW-SC
SW-POD
0
25
50
75
100
0 0.1 1 10 100
% C
ell
Su
rviv
al
Gemcitabine (μM )
E3-SC
E3-POD
11
NF-ΚB GENE EXPRESSIONS
We’ve shown that PODXL knock down is more sensitive to GE than
control SW1990. In the following figures we present the NF-κB genes
expressions in four conditions: SW control (SW SC), SW PODXL Knockdown (SW
KD), SW control treated with GE (SW GE SC), and SW PODXL Knockdown treated
with GE (SW GE KD). Tumor cells were treated with GE for 24 hours. NF-κB
targeted genes are anti-apoptotic; therefore a more GE-sensitive cell line would
expect lower NF-κB gene expressions. Our data agrees with the prediction except
for a little deviation. The Results are shown as follows.
FIGURE 3 CYCLIN D1 GENE EXPRESSIONS ON SW1990 PANCREATIC CANCER CELLS. FROM LEFT TO RIGHT:
CONTROL, PODXL KNOCKDOWN, CONTROL WITH GE TREATMENT, AND PODXL KNOCKDOWN WITH GE
TREATMENT.
12
FIGURE 4 C-MYC GENE EXPRESSIONS ON SW1990 PANCREATIC CANCER CELLS. FROM LEFT TO RIGHT: CONTROL,
PODXL KNOCKDOWN, CONTROL WITH GE TREATMENT, AND PODXL KNOCKDOWN WITH GE TREATMENT.
FIGURE 5 BCL-2 GENE EXPRESSIONS ON SW1990 PANCREATIC CANCER CELLS. FROM LEFT TO RIGHT: CONTROL,
PODXL KNOCKDOWN, CONTROL WITH GE TREATMENT, AND PODXL KNOCKDOWN WITH GE TREATMENT.
13
FIGURE 6 BCL-XL GENE EXPRESSIONS ON SW1990 PANCREATIC CANCER CELLS. FROM LEFT TO RIGHT: CONTROL,
PODXL KNOCKDOWN, CONTROL WITH GE TREATMENT, AND PODXL KNOCKDOWN WITH GE TREATMENT.
FIGURE 7 CIAP1 GENE EXPRESSIONS ON SW1990 PANCREATIC CANCER CELLS. FROM LEFT TO RIGHT: CONTROL,
PODXL KNOCKDOWN, CONTROL WITH GE TREATMENT, AND PODXL KNOCKDOWN WITH GE TREATMENT.
14
FIGURE 8 COX2 GENE EXPRESSIONS ON SW1990 PANCREATIC CANCER CELLS. FROM LEFT TO RIGHT: CONTROL,
PODXL KNOCKDOWN, CONTROL WITH GE TREATMENT, AND PODXL KNOCKDOWN WITH GE TREATMENT.
FIGURE 9 MMP9 GENE EXPRESSIONS ON SW1990 PANCREATIC CANCER CELLS. FROM LEFT TO RIGHT: CONTROL,
PODXL KNOCKDOWN, CONTROL WITH GE TREATMENT, AND PODXL KNOCKDOWN WITH GE TREATMENT.
15
Cyclin D1 gene overexpresses in SW GE SC but had insignificant difference
in expressions on other three conditions. C-Myc gene expresses the same in both
control and gemcitabine treated cells, but greatly reduced in both PODXL
knockdown conditions. Bcl2 gene expressions are very interesting because it
decreased 1 fold in SW GE KD, which supports the argument that PODXL KD
increases the sensitivity of SW cell line to GE. Bcl-xl gene expressions decrease
for 2 folds in SW KD, but are also lowered in both GE conditions. Ciap1 gene
expressions have no significant difference in GE treated and GE non-treated but
show a consistent decrease in the KD conditions. Cox-2 expression is significantly
lowered in SW GE KD, while still appears to have a consistent reduction in the KD
condition compared to SC condition. MMP-9 gene expression decreases in both
KD conditions though it has no direct apoptotic effect. Since all the NF-κB genes
are pro survival to cell apoptosis, downregulated gene expressions in the SW GE
KD condition would be favorable to our prediction.
DISCUSSION
The focus of this work is to discover the reason of increased sensitivity of
PODXL knockdown pancreatic cancer cells to GE in mRNA level. PODXL is a
transmembrane protein involved in hematopoietic cell homing, kidney
morphogenesis, breast cancer progression, and epithelial cell polarization. [33] It
is also a selectin binding ligand on pancreatic cancer cells. On the other hand, GE
16
is taken up by cells through the aid of human equilibrative nucleoside
transporter 1 and 2 (hENT1, 2) and eventually incorporates into DNA to cause
apoptosis through series of phosphorylation. We also know that GE resistance is
connected to PI3K/Akt/ NF-κB pathways. There seems to be very little
connection between PODXL and GE. However, in a very recent astrocytoma study,
PODXL overexpression was shown to promote astrocytoma cell survival against
chemotherapeutic drug temozolomide by significantly increased
phosphorylation of Akt. [34] Interestingly, our work shows that down regulation
of PODXL inhibits cell survival against gemcitabine. Instead of being a nucleoside
analogue like gemcitabine, temozolomide damages the DNA by methylation and
causes apoptosis. Though those are two separate studies with different cells and
drugs, both indicate the significance of PODXL in cancer cell survival. Combining
our result with the astrocytoma and temozolomide study, it is logical to suggest
that PODXL expression influences both NF-κB and Akt in gemcitabine resistance.
Further investigation is required to confirm and generalize this statement.
Another early study suggested that NF-κB activity grants resistance to
pancreatic cancer cells while PI3K/Akt seem to be less important against
gemcitabine. [35] In this study they alter the gemcitabine dosage from 0.4 to 20
μM treating five pancreatic cell lines and observed that NF-κB induction was
dose-dependent while PI3K/Akt activity was dose-independent. In our NF-κB
gene expression results, bcl-2, bcl-xL, and cox-2 showed reduction upon PODXL
knockdown with GE treatment compare to control. We randomly tested
gemcitabine concentration of 10 μM and the differences in gene expressions
17
among different conditions were significant. A GE dosage and time dependent
assay on PODXL knockdown would be a plus to our work. For example, assessing
NF-κB gene expressions by altering the GE concentration profile with fixed
treatment time and vise versa. (Alter time, fixed concentration). Further work is
required to confirm the correlation between GE concentration and
chemoresistance due to the PI3K/Akt mechanism.
So far we have discussed what is happening inside the cell, now lets look
at the uptake efficiency of GE and the possible correlation among hENTs and
PODXL and GE. GE moves through cell membrane by the aid of hENT1 and
hENT2. High expression of hENT1 in stage I to VI pancreatic patients showed
improved overall survival upon treatment of GE. [36] However, a recent study
reported that inhibition of hENT1 transporter does not affect the cytotoxicity of
gemcitabine on resistant pancreatic cancer cells. Additionally, the common
proposals for chemoresistance of most nucleoside analogs are the lack of
intracellular transport proteins and the dysregulation of intracellular enzymes.
[32] Therefore it is reasonable to suggest that PODXL expression affects GE
resistance by interrupting the intracellular signaling pathways but a test for the
cellular uptake of GE through the cell membrane could further confirm whether
GE cellular uptake is affected upon PODXL knockdown.
In conclusion, we’ve shown downregulation of PODXL promotes cell
death against gemcitabine and affects the mRNA expression of NF-κB targeted
18
genes. Future investigation on the Akt/PI3K signaling pathway would give a
more complete picture of GE resistance in pancreatic cancer. In fighting
chemoresistance, blocking key proteins could improve response to a common
chemotherapy drug. In a paclitaxel study, it has been reported that stabilizing
microtubules by blocking certain proteins could enhance the cytotoxic response.
[37] We do not yet know the mechanism behind the increased cytotoxic effect on
GE-PODXL, but the increased cytotoxic effect of GE-PODXL itself is already a very
good start. Besides investigating the signaling pathways of this increased
cytotoxic effect, an in vitro cytotoxicity test of GE on control SW1990 with
pharmacological inhibition of PODXL would strengthen our work. Eventually this
would lead to higher drug efficacy, improved IC50, and better overall survival
rate to the gemcitabine chemo treatment in pancreatic cancer
19
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CURRICULUM VITAE
Billy Huang
857-233-6171 | billyhuang14@gmail.com
110 River Dr. #2205, Jersey City, NJ, 07310
Education
Johns Hopkins University, Baltimore, MD Dec 2014
Master of Science in Chemical & Biomolecular Engineering,
Concentration in Molecular and Cellular Biotechnology
GPA: 3.7/4.0 Johns Hopkins University, Baltimore, MD May 2013
Bachelor of Science in Chemical & Biomolecular Engineering
Concentration in Molecular and Cellular Biotechnology
Design & Research Experience
JHU Cell Engineering and Molecular Biology Lab, Baltimore, MD May 2011- Dec 2014
Graduate Researcher
Specializes in cell-based assay development for biomarker identification and mechanism of drug resistance in pancreatic cancer cells and gene targeting and profiling
Designed and led a team project of a group of 3 on investigation of drug sensitivity on Podocalyxin knockdown cell line
Manages undergraduate research team and optimized overall lab process workflow by implementing an integrated lab equipment rotation system across multiple laboratories
Project in Design: Pharmacokinetics/ Pharmacodynamics, Baltimore, MD Sep 2013 – May 2014
Project Leader
Developed a pharmacology model that predicts the relationship between smoking and drinking behaviors for heavy smoker/drinker
Collaborated with Biomedical Engineering department to improve current type II diabetes treatments in weekly progress review meetings and PowerPoint presentations
Biochemical Engineer Senior Product Design Project, Baltimore, MD Sep 2012 - May 2013
Project Leader
Designed and transformed a snail slime-based product that targeted a niche market into an oral gel treatment for periodontal disease and preventative treatment with a larger addressable market
Conducted market analysis and developed business proposal to pitch to potential investors
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Co-authored 60 page report detailing initial design concepts, quality control methods, product efficacy data, and targeted indication
Institute of Nanobiotechnology (INBT), Baltimore, MD Sep 2010 - May 2011
Research Assistance
Assisted in improving and modifying the microfluidic cell-based assays for protein-cell binding study, gene analysis in live cells
Organized and coordinated administrative duties (e.g., lab equipment rotation schedule) to facilitate more efficient laboratory activities
Activities
Johns Hopkins Business and Consulting Club Sep 2013 - Present
2013 Mini Case Competition Participant Johns Hopkins University Symphony Orchestra Sep 2009- Dec 2012
First Violinist, Second Stand 10+ concert performances
Representative, Taiwanese Student Association Sep 2009 - Present
Hosted 20+ intercultural events with average 50+ participants Introduced and executed new growth strategy in 2010 resulting in significant expansion
of the association Technical Skills & Languages
Technical Skills: MATLAB, JAVA, ImageJ
Language: Fluent in Mandarin Chinese; Proficient in Taiwanese
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