BACKGROUND OF THE INVENTION
1. Field of the Invention
[0001] The present invention relates to methods for determining Parkinson's disease in human
patients.
2. Brief Description of the Background Art
[0002] Parkinson's Disease (PD) is a highly specific degeneration of dopamine-containing
cells of the substantia nigra of the midbrain, causing a dopamine deficiency in the
striatum. PD currently affects about 10 million people worldwide. Effective management
of a patient with PD is possible in the first 5-7 years of treatment, after which
time a series of often debilitating complications, together referred to as Late Motor
Fluctuations (LMF), occur. It is believed that treatment with levodopa ((-)-L-α-amino-beta-(3,4-dihydroxybenzene)
propanoic acid), or L-dopa, the most effective anti-Parkinson drug, may facilitate
or even promote the appearance of LMF. Dopamine agonists are employed as a treatment
alternative, but they do not offer the same degree of symptomatic relief to patients
as L-dopa does.
[0003] Symptomatic therapies improve signs and symptoms without affecting the underlying
disease state. Levodopa increases dopamine concentration in the striatum, especially
when its peripheral metabolism is inhibited by a peripheral decarboxylase inhibitor
(PDI). Levodopa/PDI therapy is widely used for symptomatic therapy for Parkinson's
disease, such as combinations with levodopa, with carbidopa ((-)-L-α-hydrazino-α-methyl-beta-(3,4-dihydroxybenzene)
propanoic acid monohydrate), levodopa and controlled release carbidopa, levodopa and
benserazide, levodopa plus controlled release benserazide (2-Amino-3-hydroxy-propionic
acid N'-(2,3,4-trihydroxy-benzyl)-hydrazide).
[0004] Catechol-O-methyltransferase (COMT) inhibitors enhance levodopa treatment as they
inhibit levodopa's metabolism, enhancing its bioavailability and thereby making more
of the drug available in the synaptic cleft for a longer period of time. Examples
of COMT inhibitors include tolcapone (3,4-dihydroxy-4'-methyl-5-nitrobenzophenone)
and entacapone ((E)-2-cyano-3-(3,4-dihydroxy-5-nitrophenyl)-N,N-diethyl-2-propenamide).
[0005] Dopamine agonists provide symptomatic benefit by directly stimulating post-synaptic
striatal dopamine receptors. Examples include bromocriptine ((5α)-2-Bromo-12'-hydroxy-2'-(1-methylethyl)-5'-(2-methylpropyl)erg-
otaman-3',6',18-trione), pergolide (8B-[(Methylthio)methyl]-6-propylergoline), ropinirole
(4-[2-(Dipropylamino)ethyl]-1,3-dihydro-2H-indol-2-one), pramipexole ((S)-4,5,6,7-Tetrahydro-N
6-propyl-2,6-benzothiazolediamine), lisuride (N'-[(8α)-9,10-didehydro-6-methylergolin-8-yl]-N,N-diethyl-
urea), cabergoline ((8β)-N-[3-(Dimethylamino)propyl]-N-[(ethylamino)carbonyl]-6-(2-propenyl)ergoline-8-carboxamide),
apomorphine ((6aR)-5,6,6a,7-Tetrahydro-6-methyl-4 H-dibenzo[de,g]quinoline-10,11-diol),
sumanirole (5-(methylamino)-5,6-dihydro-4H-imidazo {4,5,1-ij}quinolin-2(1H)-one),
rotigotine ((-)(S)-5,6,7,8-tetrahydro-6-[propyl[2-(2-thienyl)ethyl]amino]-1-naphthol-),
talipexole (5,6,7,8-Tetrahydro-6-(2-propenyl)-4H-thiazolo[4,5-d]azepin-2-amine), and
dihydroergocriptine (ergotaman-3 ',6', 18-trione,9,10-dihydro-12'-hydroxy-2'-methyl-5'-(phenylmethyl)
(5' cc)). Dopamine agonists are effective as monotherapy early in the course of Parkinson's
disease and as an adjunct to levodopa in more advanced stages. Unlike levodopa, dopamine
agonists directly stimulate post-synaptic dopamine receptors. They do not undergo
oxidative metabolism and are not thought to accelerate the disease process.
[0006] Amantidine (1-Aminotricyclo (3,3,1,1
3,7) decane) is an antiviral agent that was discovered by chance to have anti-Parkinsonian
activity. Its mechanism of action in PD has not been established, but is believed
to work by increasing dopamine release. Patients who receive amantidine either as
monotherapy or in combination with levodopa show improvement in akinesia, rigidity
and tremor.
[0007] Other medications used in the treatment of Parkinson's disease include MAO-B inhibitors.
Inhibition of L-dopa metabolism through inactivation of the monoamino oxidase type
B (MAO-B) is an effective means of enhancing the efficacy of both endogenous residual
dopamine and that exogenously derived from its precursor, L-dopa. Selegiline (methyl-(1-methyl-2-phenyl-ethyl)-prop-2-ynyl-amine)
is a MAO-B inhibitor. There is evidence that treatment with selegiline may slow down
disease progression in PD by blocking formation of free radicals derived from the
oxidative metabolism of dopamine. Other examples of MAO B inhibitors include lazabemide
(N-(2-Aminoethyl)-5-chloro-2-pyridinecarboxamide), rasagiline (N-propargyl-1-(R)aminoindan
and caroxazone (2-oxo-2H-1,3-benzoxazine-3(4H)-acetamide).
[0008] It is imperative to diagnose individuals with PD at an early stage to increase the
efficacy of therapeutic agents. However, there are neither any objective tests nor
established biomarkers for diagnosing PD. Moreover, the heterogeneity, subtypes and
progression of the disease make it difficult to develop specific therapeutic candidates.
[0009] MicroRNAs ("miRNAs) are a class of non-coding RNAs that play key roles in the regulation
of gene expression. miRNAs act at the post-transcriptional level and fine-tune the
expression of as much as 30% of all mammalian protein-encoding genes. Mature miRNAs
are short, single-stranded RNA molecules approximately 22 nucleotides in length. miRNAs
may be encoded by multiple loci, and may be organized in tandemly co-transcribed clusters.
miRNA genes are transcribed by RNA polymerase II as large primary transcripts (pri-microRNA)
that are processed by a protein complex containing the RNase III enzyme Drosha, DGCR8
and other cofactors, to form an approximately 70 nucleotide precursor microRNA (pre-miRNA).
(
Cathew RW, Cell, 2009;
Kim VN, Nat Rev Mol Cel Biol, 2009;
Siomi H, Mol Cel, 2010;
Bartel DP, Cell, 2004;
Lee Y, Nature 2003;
Han J, Genes Dev, 2004.) Pre-miRNA is transported to the cytoplasm by Exportin-5 where it is processed by
DICER, a second RNase III enzyme, together with TRBP, PACT and Ago2 in the RNA Induced
Silencing Complex resulting in miRNA duplexes (
Kim VN, Nat Rev Mol Cel Biol, 2009;
Gregory RI, Nature 2004;
MAcRae IJ, PNAS, 2008). The guide strands of miRNA duplexes separate and associate with Ago 2 for incorporation
into a ribonuclear particle to form the RNA-induced silencing complex RISC that mediates
gene silencing. The mechanisms of miRNA range from direct degradation or silencing
of mRNA and repression of translation to post-transcriptional upregulations. (
MacRae IJ, PNAS, 2008.)
[0010] The presence of miRNAs has been reported in body fluids including blood, cerebrospinal
fluid (CSF), plasma, serum and saliva at detectable levels. The tissue-specificity
of miRNAs suggests their vital and integral role in various physiological processes.
The tissue-enrichment promises a new but less explored role as diagnostic biomarker
and potential therapeutic target. Circulating miRNAs are understood to originate from
passive leakage from damaged tissue as a result of cell lysis or apoptosis, active
transport from cells via microvesicles, such as exosomes, or bound within RISC protein
complexes (Etheridge et al, 2011). Exosome and osmotic pump-mediated delivery of small
RNA molecules to the brain and CNS, respectively, provides a solution to overcoming
the limitations of miRNA-based therapies (Alvarez-Erviti et al., 2011;
Koval et al, 2013, Hum. Mol. Gen). miRNA has been demonstrated to be exceptionally stable and thus present as powerful
candidates to be potential biomarkers (Chen et al, 2008; Grasso, 2014).
SUMMARY OF THE INVENTION
[0011] It is an object of the present invention to identify miRNAs relevant to patients
suffering from Parkinson's disease.
[0012] It is another object of the present invention to provide methods for determining
patients suffering from Parkinson's disease.
[0013] These objects and others are achieved by the present invention, which provides miRNA
biomarkers that may be used in pairs or in combination to determine patients suffering
from Parkinson's disease. The scope of the invention is defined by the appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014]
Figure 1 shows the mean fold change of three PARKmiRNAs between PD patients and healthy
controls;
Figure 2A is a ROC analysis based on predicted probabilities from the model and compared
to true disease status;
Figure 2B is a ROC analysis based on predicted prohibition from the model;
Figure 3 is a ROC analysis based on predicted probabilities from the model and compared
to true disease status;
Figure 4 is a ROC analysis based on predicted probabilities from the model and compared
to true disease status;
Figure 5 is a ROC analysis based on predicted probabilities from the model and compared
to true disease status;
Figure 6(A)-(H) illustrate microRNAs targeting Parkinson's Disease proteins;
Figure 7 is a ROC analysis based on predicted probabilities from the model and compared
to true disease status;
Figure 8 is a ROC analysis based on predicted probabilities from the model and compared
to true disease status;
Figure 9 is a ROC analysis based on predicted probabilities from the model and
compared to true disease status; and
Figure 10 is a ROC analysis based on predicted probabilities from the model and compared
to true disease status.
DETAILED DESCRIPTION OF THE INVENTION
METHODS
Serum samples handling and classification
[0015] All patients and controls participated in the Norwegian ParkWest project or the Swedish
NYPUM study, which are ongoing prospective population-based longitudinal cohort studies
investigating the incidence, neurobiology and prognosis of PD. The Norwegian ParkWest
study is a prospective longitudinal multicenter cohort study of patients with incident
Parkinson's disease (PD) from
Western and Southern Norway. Between November 1st 2004 and 31 st of August 2006 it was
endeavored to recruit all new cases of Parkinson Disease within the study area. Since
the start of the study 212 of 265 (80 %) of these patients and their age-/sex-matched
control group have been followed. Further information about this project can be found
at http://
www.parkvest.no. The NYPUM study began in 2004 and endeavours to identify all new cases with idiopathic
parkinsonism within the Umeå catchment area and follow them in their disease progression
for at least five years. Further information about this study can be found at http://www.ufbi.umu.se/english/collaborations/current-projects/nypum/.
[0016] All possible efforts were undertaken to establish an unselected and population-representative
cohort of patients with PD. Patients were included if they had provided serum at study
entry and fulfilled diagnostic criteria for PD of the National Institute of Neurological
Disorders and Stroke (
http://www.ninds.nih.gov/disorders/parkinsons_disease/parkinsons_disease.ht m) and UK Brain Bank (
http://www.ncbi.nlm.nih.gov/projects/gap/cgi-bin/GetPdf.cgi?id=phd000042) at latest follow-up. Patients with secondary parkinsonism at study entry were excluded
from this study. Control subjects were recruited from multiple sources, including
friends, spouses, and public organizations for elderly and were included in this study
if they had provided serum. All patients and controls were Caucasian.
[0017] In this study of possible biomarkers for PD we applied a two-stage procedure. For
the first discovery phase serum from 16 patients and 8 controls were selected at random.
The remaining 164 patients with PD and 182 controls that were eligible for this study
were selected for verification purposes.
[0018] Serum samples were collected at the same day as the clinical examinations and then
stored frozen at -70 degrees Celsius until transported to the facilities in New York
on dry ice.
Example 1: Analyses of differentially expressed human miRNA by qPCR
RNA Isolation from serum samples and QC
[0019] After thawing on ice, twenty-four (eight control, sixteen PD samples) serum samples
were spun down for 5 mins at 3000xg to remove debris. The supernatant was used to
perform small RNA isolation using miRCURY RNA Isolation Kit - Biofluids (Exiqon, MA).
Before RNA Isolation, the lysis buffer was spiked with 0.267fmol/ul of spike-in control
cel-miR-39-3p (Qiagen, CA). The remaining part of the RNA isolation was performed
following manufacturer's protocol and the isolated RNA was quantified on a Nanodrop
2000 (Thermo Scientific, MA). The RNA was used for running Affymetrix v4 microRNA
microarray chips and for subsequent cDNA synthesis and qPCR. RNA from 434 serum samples
(22 control and 42 PD from NYPUM study in addition to 190 control and 180 PD from
ParkWest project) was isolated as described above, they were not quantified by Nanodrop,
but the qPCR data resulting from these samples were normalized by a reference small
RNA scaRNA17.
miRNA microarray and data analysis
[0020] The isolated RNA from twenty-four patient serum samples were quantified and subjected
to Affymetrix GeneChip
® miRNA 4.0 Array by the Yale Center for Genome Analysis (
http://medicine.yale.edu/keck/ycga/index.aspx). The normalized .CEL files obtained from Affymetrix Expression Console software
were imported into Partek Genomics Suite version 6.6 Copyright
© 2012 (Partek, MO) for analysis. The 'microRNA Expression Workflow' was employed to
detect differentially expressed miRNAs employing ANOVA resulting in lists of miRNAs
significantly (p<0.05) expressed between control versus PD cohorts. The miRNAs detected
were used for further qPCR verification.
Quantitative Polymerase Chain Reaction
[0021] cDNA for miRNA specific qPCR was synthesized using qScript
™ microRNA cDNA Synthesis kit (Quanta Biosciences, MD) following manufacturer's protocol
and subsequent qPCRs were performed using miRNA specific forward primers (Table#)
and PerfeCTa
®Universal PCR primer (Quanta Biosciences, MD). scaRNA17 and U6 were used reference
small RNAs for normalizing qPCR Cq values whereas cel-miR-39-3p was used as spike-in
control. PerfeCTa
® SYBR
® GREEN SuperMix for IQ
™ (Quanta Biosciences, MD) was used for all qPCRs in a MyiQ
™ Single color Real-Time PCR Detection System (Bio-Rad, CA). Standard curve for cel-miR-39-3p
was analyzed in MS Excel with R
2 = 0.97882 and PCR efficiency 92.96%. No Template Control (NTC) was implied wherever
needed.
Data analysis based on PD model
[0022] The discriminative ability of miRNAs with regard to PD diagnosis was assessed from
ROC analysis using IBM SPSS Statistics, version 21; for combinations of miRNAs the
test variable was the predicted probability from logistic regression with PD diagnosis
(yes/no) as outcome. To minimize the influence of outlying values on the fit, logistic
regression was performed with log transformed miRNA values.
[0023] Differentially expressed human miRNAs in Parkinson's disease patients' serum samples
from The Norwegian ParkWest study were determined employing miRNA microarray. Provided
below are the miRNAs with >1.2 fold differential expression.
85 differentially expressed human pre- and mature miRNAs with >1.2 fold change
[0024] hsa-miR-548ac, hsa-miR-335-5p, hsa-miR-548x-3p, hsa-miR-520g, hsa-miR-520h, hsa-miR-548ae,
hsa-miR-3910-1, hsa-miR-4708-3p, hsa-miR-16-2-3p, hsa-miR-603, hsa-miR-3613-3p, hsa-miR-4797-5p,
hsa-miR-548aj-3p, hsa-miR-450b-5p, hsa-miR-548ap-3p, hsa-miR-1184, hsa-miR-2277-5p,
hsa-miR-1323, hsa-miR-548aa, hsa-miR-548t-3p, hsa-miR-221-5p, hsa-miR-190a-3p, hsa-miR-6873-5p,
hsa-miR-155-3p, hsa-miR-510-5p, hsa-miR-4313, hsa-miR-3616, hsa-miR-8075, hsa-miR-4306,
hsa-miR-6776, hsa-miR-6075, hsa-miR-8052, hsa-miR-532, hsa-miR-4791, hsa-miR-320b-1,
hsa-miR-548y, hsa-miR-7973, hsa-miR-3136-5p, hsa-miR-606, hsa-miR-500a-3p, hsa-miR-4788,
hsa-miR-4769-3p, hsa-miR-299-5p, hsa-miR-4431, hsa-miR-6749-5p, hsa-miR-138-2-3p,
hsa-miR-1289-2, hsa-miR-548au, hsa-miR-6850, hsa-miR-561, hsa-miR-34b-5p, hsa-miR-3934-5p,
hsa-miR-6739-5p, hsa-miR-4325, hsa-miR-4672, hsa-miR-215-5p, hsa-miR-4685-5p, hsa-miR-3160-1,
hsa-miR-3160-2, hsa-miR-6793-5p, hsa-miR-8089, hsa-miR-6081, hsa-miR-892b, hsa-miR-936,
hsa-miR-548ag, hsa-miR-345, hsa-miR-548k, hsa-miR-3188, hsa-miR-181b-5p, hsa-let-7e,
hsa-miR-4487, hsa-miR-509-3p, hsa-miR-3689a-3p, hsa-miR-4771, hsa-miR-520a-5p, hsa-miR-3150b,
hsa-miR-6782-5p, hsa-miR-937-5p, hsa-miR-455-3p, hsa-miR-6865-3p, hsa-miR-4749-5p,
hsa-miR-378b, hsa-miR-7706, hsa-miR-4445 and hsa-miR-2355-5p.
57 differentially expressed mature miRNAs with >1.2 fold change
[0025] hsa-miR-548ac, hsa-miR-335-5p, hsa-miR-548x-3p, hsa-miR-548ae, hsa-miR-4708-3p, hsa-miR-16-2-3p,
hsa-miR-603, hsa-miR-3613-3p, hsa-miR-4797-5p, hsa-miR-548aj-3p, hsa-miR-450b-5p,
hsa-miR-548ap-3p, hsa-miR-1184, hsa-miR-2277-5p, hsa-miR-1323, hsa-miR-548aa, hsa-miR-548t-3p,
hsa-miR-221-5p, hsa-miR-190a-3p, hsa-miR-6873-5p, hsa-miR-155-3p, hsa-miR-510-5p,
hsa-miR-4313, hsa-miR-4306, hsa-miR-8052, hsa-miR-4791, hsa-miR-7973, hsa-miR-3136-5p,
hsa-miR-606, hsa-miR-500a-3p, hsa-miR-4769-3p, hsa-miR-299-5p, hsa-miR-6749-5p, hsa-miR-138-2-3p,
hsa-miR-34b-5p, hsa-miR-3934-5p, hsa-miR-6739-5p, hsa-miR-4325, hsa-miR-215-5p, hsa-miR-4685-5p,
hsa-miR-6793-5p, hsa-miR-936, hsa-miR-548ag, hsa-miR-548k, hsa-miR-181b-5p, hsa-let-7e,
hsa-miR-509-3p, hsa-miR-3689a-3p, hsa-miR-4771, hsa-miR-520a-5p, hsa-miR-6782-5p,
hsa-miR-937-5p, hsa-miR-455-3p, hsa-miR-6865-3p, hsa-miR-4749-5p, hsa-miR-378b and
hsa-miR-2355-5p.
28 differentially expressed premature miRNAs with >1.2 fold change
[0026] hsa-miR-520g, hsa-miR-520h, hsa-miR-3910-1, hsa-miR-3616, hsa-miR-8075, hsa-miR-6776,
hsa-miR-6075, hsa-miR-532, hsa-miR-320b-1, hsa-miR-548y, hsa-miR-4788, hsa-miR-4431,
hsa-miR-1289-2, hsa-miR-548au, hsa-miR-6850, hsa-miR-561, hsa-miR-4672, hsa-miR-3160-1,
hsa-miR-3160-2, hsa-miR-8089, hsa-miR-6081, hsa-miR-892b, hsa-miR-345, hsa-miR-3188,
hsa-miR-4487, hsa-miR-3150b, hsa-miR-7706 and hsa-miR-4445.
Example 2: Verification of human mature miRNAs by qPCR in sample cohort of 16 patients and
8 controls
[0028] The mean fold change for hsa-miR-335-5p, hsa-miR-3613-3p and hsa-miR-6865-3p PARKmiRs
between PD patients and healthy controls are shown below in Table 2 and illustrated
in Figure 1.
Table 2
| PARKmiR |
Fold change |
Significance |
| hsa-miR-335-5p |
1.64 |
0.02 |
| hsa-miR-3613-3p |
2.16 |
0.004 |
| hsa-miR-6865-3p |
1.65 |
0.03 |
Example 3: Analyses of hsa-miR-335-5p and hsa-miR-6865-3p in a cohort of 346 individuals (182
control and 164 PD serum samples) from
Norwegian ParkWest study
[0029] The qPCR technique of Example 2 was used to identify potential diagnostic biomarkers.
It was determined that combinations of hsa-miR-335-5p and hsa-miR-6865-3p show high
predictability for PD diagnosis. The results of the model with hsa-miR-335-5p and
hsa-miR-6865-3p, Outcome = PD (YES/NO), n = 164 cases + 182 controls are shown below
in Table 3.
Table 3: Statistical analysis of individual and combination of PARKmiRs from 164 PD
patients and 182 controls
| miRNA(s) |
Patients (n=164) median (IQR) |
Controls (n=182) median (IQR) |
p1 |
AUC (95% CI) |
p2 |
| 335 |
1.4 (0.5 to 2.7) |
0.12 (0.06 to 0.22) |
< 0.001 |
0.90 (0.87 to 0.93) |
< 0.001 |
| 6865 |
2.7 (1.1 to 6.9) |
1.0 (0.8 to 1.5) |
< 0.001 |
0.74 (0.69 to 0.80) |
< 0.001 |
| 3613 |
0.41 (0.19 to 0.92) |
0.21 (0.09 to 0.49) |
< 0.001 |
0.65 (0.59 to 0.71) |
< 0.001 |
| 335/6865 |
|
|
|
0.90 (0.87 to 0.93) |
< 0.001 |
| 335/3613 |
|
|
|
0.90 (0.87 to 0.94) |
< 0.001 |
[0030] ROC analysis based on predicted probabilities compared to true disease status is
depicted in Figure 2a, and show strong discriminating ability. The area under the
curve of Figure 2a is provided in Table 3 above.
Example 4: Analyses of hsa-miR-335-5p and hsa-miR-3613-3p in a cohort of 346 individuals (182
control and 164 PD serum samples)
[0031] Following the protocol of Example 3 it was determined that combinations of hsa-miR-335-5p
and hsa-miR-3613-3p also show high predictability for PD diagnosis. The results of
the model with hsa-miR-335-5p and hsa-miR-3613-3p, Outcome = PD (YES/NO), n = 164
cases + 182 controls are shown above in Table 3.
[0032] ROC analysis based on predicted probabilities from the model showing strong discriminating
ability are depicted in Figure 2b. The area under the curve of Figure 2b is provided
in Table 3 above.
[0033] From the foregoing Examples 1-4 it is evidenced that any combination of two or more
microRNAs from the list of 85 identified miRNAs can be used to diagnose the occurrence
of PD in patients.
Example 5: hsa-miR-335-5p
[0034] Table 3 above illustrates that hsa-miR-335-5p shows high predictability for PD diagnosis
for Outcome = PD (YES/NO), n = 164 cases + 182 controls.
[0035] ROC analysis based on probabilities from the model and compared to true disease status
showing strong discriminating ability is shown in Figure 3. The area under the curve
of Figure 3 is provided in Table 3 above.
Example 6: has-miR-3613-3p
[0036] hsa-miR-3613-3p also shows high predictability for PD diagnosis as illustrated in
Table 3 above. ROC analysis based on probabilities from the model and compared to
true disease status showing strong discriminating ability is shown in Figure 4. The
area under the curve of Figure 4 is provided in Table 3 above.
Example 7: has-miR-6865-3p
[0037] Similarly, hsa-miR-6865-3p also shows high predictability for PD diagnosis as shown
in Table 3 above. ROC analysis based on probabilities from the model and compared
to true disease status showing strong discriminating ability is shown in Figure 5.
The area under the curve of Figure 5 is provided above in Table 3.
[0038] From the foregoing Examples 5-7, it is evidenced that hsa-miR-335-5p, hsa-miR-3613-3p
and hsa-miR-6865-3p may be used individually for accurate diagnosis of PD.
Example 8: Analyses of hsa-miR-335-5p and hsa-miR-6865-3p in a cohort of 64 individuals (22
control and 42 PD serum samples) from
Swedish NYPUM study
[0039] The qPCR technique of Example 2 was used to validate the diagnostic biomarkers of
Example 2. It was determined that combinations of hsa-miR-335-5p and hsa-miR-6865-3p
show high predictability for PD diagnosis. The results of the model with hsa-miR-335-5p
and hsa-miR-6865-3p, Outcome = PD (YES/NO), n = 42 cases + 22 controls are shown below
in Table 4.
Table 4: Statistical analysis of individual and combinations of PARKmiRs from 42 PD
patients and 22 controls from the NYPUM study.
| miRNA(s) |
Patients (n=42) median (IQR) |
Controls (n=22) median (IQR) |
p1 |
AUC (95% CI) |
p2 |
| 335 |
1.3 (0.79 to 2.2) |
1.1 (0.71 to 1.4) |
0.125 |
0.62 (0.48 to 0.75) |
0.127 |
| 3613 |
2.1 (1.2 to 3.3) |
1.2 (1.0 to 1.6) |
0.012 |
0.74 (0.62 to 0.86) |
0.002 |
| 6865 |
1.5 (1.2 to 2.2) |
1.2 (1.0 to 1.4) |
0.002 |
0.69 (0.56 to 0.82) |
0.012 |
| 335/3613 |
n/a |
n/a |
n/a |
0.75 (0.63 to 0.87) |
0.001 |
| 335/6865 |
n/a |
n/a |
n/a |
0.71 (0.59 to 0.84) |
0.006 |
| 3613/6865 |
n/a |
n/a |
n/a |
0.75 (0.63 to 0.87) |
0.001 |
| 335/3613/6865 |
n/a |
n/a |
n/a |
0.76 (0.64 to 0.87) |
0.001 |
[0040] ROC analysis based on predicted probabilities compared to true disease status is
depicted in Figure 7, and show strong discriminating ability. The area under the curve
of Figure 7 is provided in Table 4 above.
Example 9: Analyses of hsa-miR-335-5p and hsa-miR-3613-3p in a cohort of 64 individuals (22
control and 42 PD serum samples)
[0041] Following the protocol of Example 3 it was determined that combinations of hsa-miR-335-5p
and hsa-miR-3613-3p also show high predictability for PD diagnosis. The results of
the model with hsa-miR-335-5p and hsa-miR-3613-3p, Outcome = PD (YES/NO), n = 42 cases
+ 22 controls are shown above in Table 4.
[0042] ROC analysis based on predicted probabilities from the model showing strong discriminating
ability are depicted in Figure 8. The area under the curve of Figure 8 is provided
in Table 4 above.
Example 10: Analyses of hsa-miR-3613-3p and hsa-miR-6865-5p in a cohort of 64 individuals (22
control and 42 PD serum samples)
[0043] Following the protocol of Example 3 it was determined that combinations of hsa-miR-3613-3p
and hsa-miR-6865-5p also show high predictability for PD diagnosis. The results of
the model with hsa-miR-3613-3p and hsa-miR-6865-5p, Outcome = PD (YES/NO), n = 42
cases + 22 controls are shown above in Table 4.
[0044] ROC analysis based on predicted probabilities from the model showing strong discriminating
ability are depicted in Figure 9. The area under the curve of Figure 9 is provided
in Table 4 above.
Example 11: Analyses of hsa-miR-335-5p, hsa-miR-3613-3p and hsa-miR-6865-5p in a cohort of 64
individuals (22 control and 42 PD serum samples)
[0045] Following the protocol of Example 3 it was determined that combinations of hsa-miR-
hsa-miR-335-5p, hsa-miR-3613-3p and hsa-miR-6865-5p also show high predictability
for PD diagnosis. The results of the model with hsa-miR-335-5p, hsa-miR-3613-3p and
hsa-miR-6865-5p, Outcome = PD (YES/NO), n = 42 cases + 22 controls are shown above
in Table 4.
[0046] ROC analysis based on predicted probabilities from the model showing strong discriminating
ability are depicted in Figure 10. The area under the curve of Figure 10 is provided
in Table 4 above.
[0047] From the foregoing Example 10 it is evidenced that any combination of three or more
microRNAs from the list of 85 identified miRNAs can be used to diagnose the occurrence
of PD in patients.
Example 12
[0048] Analysis of hsa-miR-335-5p, hsa-miR-3613-3p and hsa-miR-6865-3p targets using multiple
bioinformatics tools show that among others, LRRK2 and Parkin are predicted targets
of hsa-miR-335-5p, and SNCA is a predicted target of hsa-miR-3613-3p. The regulation
of LRRK2 expression in SHSY-5Y cells as a result of modulation in hsa-miR-335-5p levels
was confirmed by western blot analysis. hsa-miR-335-5p was overexpressed (Figure 6A)
and inhibited (Figure 6A) using mimic and antagomir of hsa-miR-335-5p transfected
into neuroblastoma cells. The cells were lysed after 48 hours post-transfection and
used for western blot analysis. hsa-miR-335-5p mimic showed downregulation of LRRK2
and hsa-miR-335-5p antagomir showed upregulation of LRRK2 (Figure 6B, C). The hsa-miR-3613-3p
regulated SNCA expression in SH-SY5Y cells in moderation. A similar experimental approach
like hsa-miR-335-5p was adopted for hsa-miR-3613-3p (Figure 6D) and the results showed
moderate SNCA upregulation with hsa-miR-3613-3p mimic and a moderate SNCA downregulation
with hsa-miR-3613-3p antagomir at protein level (Figure 6E, F) and transcript level
(Figure 6G).
[0049] The target discovery using LC-MS was performed to find novel targets for hsa-miR-335-5p,
hsa-miR-3613-3p and hsa-miR-6865-3p.
- a. The proteins with differential expression pattern as a result of hsa-miR-335-5p
modulation include acadsb, slc4a7, lnp/kiaa1715, supt5h, sdhd. Wdr1, cmpk1, slc25a1,
hmgcs1, twf2, ppp1r18, exoc8, tm9sf4, kif16b, dnajc2, sel1l, hectd1, gmppb.
- b. The proteins with differential expression pattern as a result of hsa-miR-3613-3p
modulation include wdr1, gmppb, hmbs, eml4, hebp1, apmap/c20orf3, sord, pcyt2, stat3,
top2a, skiv2l2, cdc20, myo1e, ttll 12, atad2, carm1, arfgap1, ppp4r1, nde1/ndel1.
- c. The proteins with differential expression pattern as a result of hsa-miR-6865-3p
modulation include wdr1, ppp1r18, ppp4r1, ube2h, ube3c, stx16, ube4h, gtf2f1, map1b,
ube2a, dusp3, arhgap1, nsun2, acox1, fkbp10, fam107b, pofut1, tomm22, hspb8, sbds.
Example 13
[0050] Measurement of levels of a combination of two or more miRNAs in serum from patients
can assist in distinctly differentiating between a potential PD patient and a healthy
individual. A serum sample is obtained from blood withdrawn from patients suspected
of PD. The serum is used for total microRNA isolation and enrichment. This RNA would
then be tested using qPCR to measure the levels of any two or more of the 85 miRNAs
mentioned in Example 1, or any one of three miRNAs mentioned in Examples 5-7. Detectable
levels of any two or more of the 85 miRNAs or any one of the three miRNAs confirms
the patient has PD. If desired, other sample fluids may be utilized, including plasma,
venous or arterial blood, or CSF samples withdrawn by lumbar puncture. Such plasma,
blood or CSF samples are processed as above. It will be understood that measurement
of more than two miRNAs in combination or a set of combinations used in a test matrix
may desirably increase the accuracy of PD diagnosis.
Example 14
[0051] Since a combination of miRNA can be used for diagnosis it may be advisable to test
all the candidates to eliminate any cohort-based variation. It is understood that
any detectable amounts of relevant miRNA will indicate PD pathology. However, those
of ordinary skill in the art recognize it may be clinically helpful to use values
of 164 v 182 samples to set an artificial threshold for diagnosis. Differential miRNA
levels can be used to develop diagnostic biomarker kits that can be used by clinicians
in diagnosis as well as in clinical trials. In this study the presence and quantification
of miRNA from serum was determined by qRT-PCR which amplifies and quantifies the RNA
is question. Other suitable techniques known to those of ordinary skill herein may
be alternatively utilized, including use of labeled antisense sequences and labeled
antibodies. Suitable antibodies are preferentially selective, referring to a binding
reaction between two molecules that is typically more than 10 to 100 times background
molecular associations under measurement conditions. Thus, under designated immunoassay
conditions, the specified antibodies bind to a particular miRNA sequence, thereby
identifying its presence. Specific binding to an antibody under such conditions requires
an antibody that is selected for its specificity for a particular miRNA. For example,
antibodies raised against a particular miRNA can be selected by subtracting out antibodies
that cross-react with other molecules. A variety of immunoassay formats may be used
to select antibodies specifically immunoreactive with a particular miRNA including
solid-phase ELISA immunoassays (see, e.g.,
Harlow & Lane, Antibodies, A Laboratory Manual (1988) for a description of immunoassay formats and conditions that can be used to determine
specific immunoreactivity). Methods for determining whether two molecules specifically
interact are disclosed therein, and methods of determining binding affinity and specificity
are well known in the art (see, for example,
Harlow and Lane, Antibodies: A laboratory manual (Cold Spring Harbor Laboratory Press,
1988);
Friefelder, "Physical Biochemistry: Applications to biochemistry and molecular biology"
(W.H. Freeman and Co. 1976)). The term "antibody" as used herein encompasses naturally occurring antibodies
as well as non-naturally occurring antibodies, including, for example, single chain
antibodies, chimeric, bifunctional and humanized antibodies, as well as antigen-binding
fragments thereof, (e.g., Fab', F(ab')2, Fab, Fv and rIgG).
See also, Pierce Catalog and Handbook, 1994-1995 (Pierce Chemical Co., Rockford, IL).
See also, e.g.,
Kuby, J., Immunology, 3rd Ed., W.H. Freeman & Co., New York (1998). Such non-naturally occurring antibodies can be constructed using solid phase peptide
synthesis, can be produced recombinantly or can be obtained, for example, by screening
combinatorial libraries consisting of variable heavy chains and variable light chains
as described by
Huse et al., Science, Vol. 246 (1989) 1275-81. These and other methods of making, for example, chimeric, humanized, CDR-grafted,
single chain, and bifunctional antibodies are well known to those skilled in the art
(
Winter and Harris, Immunol. Today, Vol. 14 (1993) 243-46;
Ward et al., Nature, Vol. 341 (1989) 544-46; Harlow and Lane, supra, 1988;
Hilyard et al., Protein Engineering: A practical approach (IRL Press 1992);
Borrabeck, Antibody Engineering, 2d ed. (Oxford University Press 1995). Methods for producing both monoclonal and polyclonal antibodies from identified
RNA sequences are well known in the art.
Example 15
[0052] Many neurodegenerative diseases are closely related to each other when it comes to
symptoms as well as pathological markers. The circulating diagnostic markers for one
neurodegenerative disease can be useful for diagnosis of other disease. A method to
diagnose other neurodegenerative diseases like Dementia with Lewy body (DLB), Amyotrophic
lateral sclerosis (ALS), Alzheimer's disease (AD), Multiple system atrophy (MSA),
CorticoBasal Degeneration (CBD), Progressive Supranuclear Palsy (PSP) can also be
developed using similar miRNA measurements of candidates mentioned above. Disease
specific kits can be developed similar to one mentioned in [0037] with various combinations
of miRNAs listed in [0019].
Example 16
[0053] The miRNAs detected in one or more combinations can regulate several proteins in
the cells. Novel protein targets for PD can be discovered using these microRNAs and
their combinations. The involvement of these proteins in PD etiology can be further
established to target them for therapy.
Example 17
[0054] We have experimentally confirmed the predicted regulation of LRRK2 by hsa-miR-335-5p
and SNCA by hsa-miR-3613-3p in dopaminergic neuronal cell lines. Therapeutic intervention
to regulate the novel targets mentioned can be achieved by RNA interference technologies.
Example 18
[0055] Small nucleic acid molecules derived from miRNAs mentioned in [0019] will be designed
to therapeutically intervene by specifically targeting genes in PD brains to achieve
complete or partial remedy. The effects shown in [0040] will be achieved for precise
targeting in brain cells.