Supplementary Information Supplementary Experimental
Document Sample


Supplementary Information
Supplementary Experimental Procedures:
Cell lines: MPNST cell lines utilized for our functional studies included the NF1-associated:
ST88-14 (provided by Dr Jonathan Fletcher, Brigham and Women’s Hospital, Boston, MA) and
the sporadic MPNST cell lines: STS26T (provided by Dr Steven Porcelli, Albert Einstein College
of Medicine, Bronx, NY) and MPNST724 (provided by Dr Jonathan Fletcher) and were
propagated and maintained as previously described (Miller SJ, et al. Cancer Res 2006;66:2584-
91). Of note, although STS26T cells exhibit a lower pMET expression in vitro as compared to
ST88 and MPNST724 (but higher the NSC) they were included in our studies as they
reproducibly grow in SCID mice (as do MPNST724 and most importantly they are the only
available MPNST cells that result in lung metastasis after tail vein injection – with the goal of
investigating effect of MET in vivo we did not exclude this cell line. Primary human adult
Schwann cell cultures established from human cauda equina nerves were provided by Dr
Patrick Wood (Miami Project, University of Miami, Miami, FL) and maintained as previously
described (Casella GT, et al. Glia, 2000;30:165–177). Human umbilical vein endothelial cells
(HUVEC; ATCC) and human dermal microvessel endothelial cells (HDMEC; PromoCell,
Heidelberg, Germany) were propagated and maintained as instructed by the respective
sources. The human leiomyosarcoma cell line SKLMS1 (ATCC) and fibrosarcoma cell line
HT1080 (ATCC) were utilized as controls for ELISA experiment.
.
Short tandem repeat (STR) DNA fingerprinting
DNA was extracted from all MPNST cell lines using the Qiagen Blood & Cell Culture DNA Maxi
kit according to the manufacturer's protocol (Qiagen, Valencia, CA). DNA fingerprints were
obtained using the AmpFlSTR Identifier PCR Amplification kit (Applied Biosystems, Foster City,
CA) according to the manufacturer's protocol. The kit amplifies the amelogenin gender-
determining marker and 15 tetranucleotide repeat loci in a single PCR amplification using 33
1
primers (the extra one is a degenerate primer targeting a mutation at the D8S1179 locus). That
combination of markers is consistent with worldwide database recommendations for identity
testing. Each of the STRs used in this study has a tetranucleotide repeat sequence. Allele calls
were made from peak plots by comparing peaks to known fragment sizes using GeneMapper
4.0 (Applied Biosystems).
Cell growth assays
MTS assays: these were conducted using CellTiter96 Aqueous Non-Radioactive Cell
Proliferation Assay kit (Promega Corp, Madison, WI), per manufacturer's instructions. Drugs
were administered at doses and for intervals as indicated. Absorbance was measured at a
wavelength of 490 nm, and the absorbance values of treated cells are presented as a
percentage of the absorbance of untreated cells. Colony formation assay: one hundred viable
cells per well were plated and allowed to grow in normal medium for 10 days and then stained
for 30 min at room temperature with a 6% glutaraldehyde, 0.5% crystal violet solution. Pictures
were captured digitally and colonies were counted. All experiments were repeated at a minimum
twice for each cell line.
Western Blotting
Briefly, 25-50 μg of proteins extracted from cultured cells or tumor tissues were separated by
SDS-PAGE and transferred onto nitrocellulose membranes. Membranes were blocked and
blotted with relevant antibodies. Horseradish peroxidase–conjugated secondary antibodies were
detected by ECL (Amersham Biosciences). IRdye680- and IRdye800-conjugated secondary
antibodies (Molecular Probes) were detected using Odyssey Imaging (LICOR Biosciences).
Migration and Invasion Assays
2
BioCoat cell culture inserts and polycarbonate filters with 8-μm pores (Becton Dickinson
Labware) in 24-well tissue culture plates were used for migration assays. Lower chamber
compartments contained DMEM supplemented by 1% bovine serum albumin or 1% fetal bovine
serum as chemoattractants. Cells (5x104) were seeded in the upper compartment and incubated
at 37°C in a humidified atmosphere of 95% air and 5% CO2 for overnight. Invasion assays were
conducted similarly using 24-well BioCoat Matrigel invasion chambers with 8-μm pore size
polycarbonate filters coated with Matrigel (Becton Dickinson Labware). After incubation, filters
were fixed with 4% formaldehyde and stained with 0.2% crystal violet (Baxter Healthcare). Cells
on the upper surface of the filters were removed by wiping with a cotton swab, and migratory
and invasive activities were determined by counting the number of cells per high-power field
(×200) that had migrated to the lower side of the filter.
qRT-PCR
Five µg total RNA was used for cDNA synthesis by RT III kit (Invitrogen, Carlsbad, CA)
according to manufacturers’ instructions. Real time quantitative PCR was performed using PCR
Master Mix (Promega, Medison, WI). The following primers were used: MMP2 forward-5′-
TGGCCCACAACCCATTTCAC-3′ and reverse 5′-TCAATGTACATGGCCTTTCCTTCAC- 3′;
GAPDH, forward 5′-GAGCCACATCGCTCAGAC-3′ and reverse 5′-
CTTCTCATGGTTCACACCC-3′. Gene expression was analyzed using a Mastercycler
Epgradients realplex (Eppendorf, Hamburg Germany). The levels of gene expression were
normalized using GAPDH levels based on the comparative threshold cycle method.
Sequencing of the MET gene
Total genomic DNA was isolated using the QIAamp DNA extraction kit (Qiagen, Venlo, The
Netherlands). Quantification of extracted DNA was performed using the NanoDrop
3
spectrophotometer (NanoDrop Technologies, Wilmington, DE). Exons 10 and 13–22 of MET
were amplified by polymerase chain reaction (PCR). Primer sequences (forward and reverse,
respectively) and PCR conditions are as follows: MET- Exon10F: -
TTGACTGTGCCTCTGACCTG- and MET- Exon10R: -GCAGAGCTCTGAGTAGAACCA-; MET-
Exon13F: -GACCAAAGTGCTACAACCTG- and MET- Exon13R: -
AGGAGACTTTGACCCAGTGC-; MET- Exon14F: -GTCGTCGATTCTTGTGTGCTG-; and MET-
Exon14R: -CAACAATGTCACAACCCACTG-; MET- Exon15F: -AGCTCTTCCTGTTTCAGTCC-
and MET- Exon15R: -CAAATCCCCACGGATATGAT-; MET- Exon16F: -
CGCAGTGCTAACCAAGTTCT- and MET- Exon16R: -TTTTCCACAAGGGGAAAGTG-; MET-
Exon17F: -AAACCCTCAGGACAAGATGC- and MET- Exon17R: -
GGCCTATTTTGAAGGGATGG-; MET- Exon19F: -TTCTATTTCAGCCACGGGTAA- and MET-
Exon19R: -CTGGAATTGGTGGTGTTGAA-. The purified PCR products were sequenced in
forward and reverse directions using the ABI PRISM BigDye Terminator Cycle Sequencing
Ready Reaction kit (Version 3) and ABI PRISM 3730 Genetic Analyzer (Applied Biosystems,
CA). Chromatograms were analyzed by SeqScape V2.5 and manual review.
Transfection/transduction procedures: siRNAs (20nM pools targeting MET and control non-
targeting constructs [Cat # D-001810-10-05; ON-TARGETplus Non-Targeting Pool Negative
control siRNA with at least four mismatches to any human gene]) were introduced into cells
using Lipofectamine 2000 (Invitrogen, Carlsbad, CA) per manufacturer’s instructions. Briefly,
2x105 cells were plated in each well of a six-well plate and incubated overnight. A mixture of
siRNA (20 nM) and Lipofectamine 2000 (10 μl) diluted in Dulbecco's modified Eagle medium
(DMEM) was added for 24 hr, followed by incubation in regular medium. Cells were harvested at
indicated time points for specific experiments. For stable anti-MET lentiviral shRNA transduction
the following two double-stranded oligonucleotide encoding MET shRNA of interest (MET1F:
GTAAAGAGGCACTAGCAAA; MET2F: CAAAGAAGGAAGTGTTTAA; MET3F:
4
AAATAAGAGCTGTGAGAAT; MET4F: GGACAATGATGGCAAGAAA ) were cloned into the
pLVTHM GFP expression vector (Addgene, Cat: 12247) to create expression plasmids.
Lentivirus were generated by cotransfection of the packing plasmid (Addgene, Cat: 12259 and
12260) and the above MET shRNA expression plasmids into 293T cells (these procedures were
conducted at the Cancer Biology Department Core Facility). The STS26T and MPNST724 cell
lines were cultured in six-well plates to which 8 μg/mL polybrene and virally infected supernatant
was added for four hours and after 48 hours selected by FACS sorting for GFP expression.
Knock down of MET was confirmed by western blot.
Gelfoam angiogenesis assay
These experiments were approved by the MD Anderson Cancer Center Institutional Animal Care
and Usage Committee. Gel-foam sponges (Pharmacia & Upjohn, Peapack, NJ) were cut into
approximately 0.5X0.5cm square fragments and saturated overnight in PBS at 4°C. The next
day, the sponges were placed on sterile filter paper to allow excess PBS to be drawn out.
Sponges were incubated with conditioned media collected from MPNST cells. To obtain
conditioned media MPNST cells were incubated in serum free overnight and in the morning
culture media containing HGF was added to the plates for 24h. Next, plates were washed and
fresh serum free culture media (i.e. not containing HGF) was added and collected after 24h.
Cells were counted and no difference in number of cells was found between HGF treated and
untreated cells. The sponges were allowed to sit at room temperature for approximately 1 hour
and then implanted subcutaneously into the flank of SCID mice (n=2/condition). Mice were
euthanized after 14 days and gel-foam sponges were harvested and frozen in OCT (Sakura
Fineter, Torrance, CA). The frozen samples were later sectioned and probed for CD31. To
evaluate the effect of XL184 on cytokine (HGF and/or VEGF) induced angiogenesis gel-foams
(suspended in these cytokines) were subcutaneously implanted and mice were assigned to two
treatment groups (n=3 mice/group): XL184 (30 mg/kg/once daily, per gavage) vs. vehicle
5
treatment control. After 10 consecutive treatment days mice were euthanized and gel foam
processed as per above.
In vivo animal models
All animal procedures and care were approved by the MD Anderson Cancer Center Institutional
Animal Care and Usage Committee. Animals received humane care as per the Animal Welfare
Act and the NIH "Guide for the Care and Use of Laboratory Animals." For experiments
evaluating effect of treatment on local tumor growth trypan blue staining confirmed viable
MPNST cells (STS26T and MPNST724; 1-2 x 106/0.1 mL HBSS/mouse) were used. Cell
suspensions were injected subcutaneously into the flank of six week old female hairless SCID
mice (n = 10/arm) and growth was measured twice weekly; after establishment of palpable
lesions (average diameter >5mm) or in a repeated experiment when tumors reached an
average size of 7-9mm in larger dimension mice were assigned to one of the following treatment
groups (only mice with tumors of similar size were included in the study; mice with very large or
small tumors were excluded thus explaining the varied number of mice per experiment): 1)
XL184 (30mg/kg/d, per gavage) or 2) control vehicle only. An experimental lung metastasis
MPNST model was used to evaluate metastases’ growth. STS26T cells (1 x 106/0.1 mL
HBSS/mouse) were injected into the tail vein of female SCID mice. A week after injection (a
time-point by which 95-100% of mice develop established lung metastases) mice were allocated
to treatment groups as per above (n=8/group). Mice were followed for tumor size, well being,
and body weight and sacrificed when control group tumors reached an average of 1.5 cm in
their largest dimension. Tumors were resected, weighed, and frozen or fixed in formalin and
paraffin-embedded for immunohistochemical studies. For lung metastasis studies mice were
followed for body weight and well being and sacrificed after three weeks of treatment. Lungs
were resected, evaluated macroscopically for tumor load and weighed. Similarly, mice were
injected (S.C. or I.V.) STS26T cells stably transduced with NTshRNA, anti-MET construct#1, or
6
anti-MET construct#4 (S.C. n=8-10 mice/cell line and I.V. n=5mice/cell line) and mice were
followed for local and metastatic growth.
7
Supplementary Tables
Table S1: MPNST cell lines DNA fingerprinting results*
AMEL CSF1PO D13S317 D16S539 D5S818 D7S820 TH01 TPOX vWA
Cell Line
STS26T
X 10,13 9,10 12,13 11,12 8,11 6,9.3 8 17
MPNST724
X 13 11,12 9,11 9,13 9,10 6 8 15,17
ST88-14 X,Y 9,12 12 13 12,13 8 9 11,12 16
*As per HIPPA regulations and Institutional policy not all markers are provided. Marker selection
followed ATCC database reporting .
8
Table S2: Univariable and multivariable Cox proportional hazard models for biomarker
expression correlation with MPNST patients’ disease specific survival (DSS)
1A. Univariable Analysis
Marker HR P value
HGF Intensity 1.03 (0.65-1.63) 0.892
% 1.01 (0.99-1.02) 0.471
MET Intensity 0.95 (0.54-1.67) 0.863
% 1.05 (0.99-1.11) 0.108
pMET Intensity 2.32 (1.20-4.48) 0.012
% 1.04 (1.02-1.06) 0.0004
1B. Multivariable Analysis
Variable HR 95 % CI p-value
P53 intensity 2.31 1.19-4.49 0.014
pMET % 1.04 1.01-1.07 0.014
Size <10 cm -- -- --
>=10 cm 2.03 0.75-5.52 0.164
Negative S100 Neg. vs. pos. 1.19 0.45-3.18 0.725
staining
9
Supplementary Figures:
Supplementary Figure 1:
Fig S1. MET activation does not impact MPNST cell proliferation. A. No significant effect on
growth of MPNST cells was found after stimulation with HGF (50µg/48h; MTS); B. Similarly, no
effect of HGF on clonogenicity was found; C. WB analysis of shRNA-mediated MET knockdown.
MPNST cells were transduced with lentiviral shRNA constructs targeting MET or non targeting
control. Constructs 1 and 4 resulted in marked MET knockdown in both cell lines and were
selected for further study; constructs 2 and 3 as well as non-targeting shRNA did not affect MET
protein levels. GFP expression in all transduced cell lines (after FACS sorting) confirms a high
10
transduction efficiency; D. MET knockdown did not significantly alter MPNST cell growth or
colony-forming efficiency
11
Supplementary Figure 2:
Fig S2: Effects of HGF and XL184 on normal human Schwann cells (NHSCs). A. WB
depicting enhanced MET phosphorylation in NHSCs (no constitutive pMET is expressed by
these cells) in response to HGF. XL184 inhibits HGF induced MET phosphorylation; B. No
significant effect on growth of NHSCs was found after stimulation with HGF (50µg/48h; MTS left
graph). Higher XL184 doses (48hr) were needed to inhibit the growth of NHSC as compared to
MPNST cells (right graph); C. HGF enhances NSCs migration and invasion and XL184 (0.5µM)
blocks HGF induced effects.
12
Supplementary Figure 3:
Fig S3: Relative MET levels and signaling after MET siRNA knockdown. Protein expression
levels in Fig 3A determined via densitometry
13
Supplementary Figure 4:
Fig S4: Impact of XL184 on constitutive MET phosphorylation and expression of XL184
potential kinase targets in MPNST cells. A. Marked dose dependent inhibition of constitutive
MET phosphorylation and its resultant downstream signaling was observed after four hour
incubation of MPNST cells (cultured in regular media without HGF stimulation) with XL184. B.
14
WB analyses depicting the expression of several potential XL184 targets in MPNST cell lines.
As shown the MPNST cells evaluated do not express VEGFR2 while endothelial cells do.
Varying levels of KIT, RET and AXL have been found.
15
Get documents about "