Metabolic Imaging for Glioblastoma
Recruiting in Palo Alto (17 mi)
Overseen byBenjamin Ellingson, PhD
Age: 18+
Sex: Any
Travel: May Be Covered
Time Reimbursement: Varies
Trial Phase: Phase 1 & 2
Recruiting
Sponsor: Jonsson Comprehensive Cancer Center
Disqualifiers: Ferromagnetic devices, Claustrophobia, Renal function, others
No Placebo Group
Trial Summary
What is the purpose of this trial?The purpose of this project is to validate a new combined MRI and PET imaging technique as a biomarker or measure of glycolysis in brain tumors. To accomplish this, the investigators propose obtaining image-guided measures of tissue pH and biopsied tissue in tumor areas selected for bulk resection surgery. Investigators will then correlate the imaging measurements with pH, RNA expression, protein expression, and bioenergetics measurements of key glycolytic enzymes.
Will I have to stop taking my current medications?
The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.
What data supports the effectiveness of the treatment pH Measurement of in vivo tissue for glioblastoma?
Research shows that measuring the acidity (pH) of the tumor environment can help understand tumor growth and response to treatments. For example, studies have used imaging techniques to map pH changes in tumors, which can indicate how well a treatment is working by showing changes in tumor size and cell activity.
12345Is metabolic imaging for glioblastoma safe for humans?
The studies primarily focus on imaging techniques in animal models, such as rats, and do not provide direct safety data for humans. However, these imaging methods are noninvasive and involve techniques like MRI, which are generally considered safe in clinical settings.
13467How does metabolic imaging differ from other treatments for glioblastoma?
Metabolic imaging for glioblastoma is unique because it uses advanced magnetic resonance techniques to map the acidity (pH) of the tumor environment, which can help guide treatment decisions by identifying areas of the tumor that may be resistant to therapy. This approach is different from standard treatments that typically focus on directly targeting tumor cells without considering the tumor's microenvironment.
13468Eligibility Criteria
This trial is for adults over 18 with new or returning glioblastoma who are scheduled for tumor removal surgery. It's not suitable for those unable to undergo MRI or PET scans, have metal implants that could be hazardous in scans, have severe kidney issues (GFR < 30), or extreme claustrophobia.Inclusion Criteria
I am older than 18 years.
I have a new or returning glioblastoma and need surgery.
Exclusion Criteria
Patients who cannot obtain an MRI or FDG PET scan with contrast
Those with ferromagnetic implanted devices that might produce a safety hazard (e.g. infusion pumps, pace makers, aneurysm clips, etc.)
My kidney function is severely reduced.
+1 more
Trial Timeline
Screening
Participants are screened for eligibility to participate in the trial
2-4 weeks
Imaging and Biopsy
Participants undergo FDG-PET scan and MRI, followed by biopsy for glycolytic index measurement and tissue analysis
1-2 weeks
1 visit (in-person)
Follow-up
Participants are monitored for safety and effectiveness after imaging and biopsy procedures
4 weeks
Participant Groups
The study is testing a novel imaging technique combining MRI and PET to measure glycolysis in brain tumors. Researchers will compare images with actual tissue samples from surgeries to see how well the imaging reflects tumor metabolism.
1Treatment groups
Experimental Treatment
Group I: Arm I en vivo Glycolic Index measurementExperimental Treatment1 Intervention
All biopsies are acquired for standard of care and according to standard of care procedures. A 13-gauge biopsy needle and plastic cannula will be inserted into the region of interest identified on MRI and PET. The biopsy needle will be removed, and the Softcell® pH probe, consisting of a 1.8mm diameter high quality glass tip and 1.6m long wire, will be guided down the cannula and inserted at least 15mm into the tissue. Recordings will be made for 1 minute to stabilize the reading, then the pH probe will be removed from the region of interest and placed into a saline vial for the next biopsy target.
Find a Clinic Near You
Research Locations NearbySelect from list below to view details:
University of California at Los AngelesLos Angeles, CA
Loading ...
Who Is Running the Clinical Trial?
Jonsson Comprehensive Cancer CenterLead Sponsor
Nitional institute of Health -National Center for Advancing Translational SciencesCollaborator
National Center for Advancing Translational Sciences (NCATS)Collaborator
References
Temozolomide arrests glioma growth and normalizes intratumoral extracellular pH. [2019]Gliomas maintain an acidic extracellular pH (pHe), which promotes tumor growth and builds resistance to therapy. Given evidence that acidic pHe beyond the tumor core indicates infiltration, we hypothesized that imaging the intratumoral pHe in relation to the peritumoral pHe can provide a novel readout of therapeutic influence on the tumor microenvironment. We used Biosensor Imaging of Redundant Deviation in Shifts (BIRDS), which utilizes chemical shifts of non-exchangeable protons from macrocyclic chelates (e.g., DOTP8-) complexed with paramagnetic thulium (Tm3+), to generate pHe maps in rat brains bearing U251 tumors. Following TmDOTP5- infusion, T2-weighted MRI provided delineation of the tumor boundary and BIRDS was used to image the pHe gradient between intratumoral and peritumoral regions (ΔpHe) in both untreated and temozolomide treated (40 mg/kg) rats bearing U251 tumors. Treated rats had reduced tumor volume (p < 0.01), reduced proliferation (Ki-67 staining; p < 0.03) and apoptosis induction (cleaved Caspase-3 staining; p < 0.001) when compared to untreated rats. The ΔpHe was significantly higher in untreated compared to treated rats (p < 0.002), suggesting that temozolomide, which induces apoptosis and hinders proliferation, also normalizes intratumoral pHe. Thus, BIRDS can be used to map the ΔpHe in gliomas and provide a physiological readout of the therapeutic response on the tumor microenvironment.
In Vivo Imaging of Tumor Metabolism and Acidosis by Combining PET and MRI-CEST pH Imaging. [2022]The vast majority of cancers exhibit increased glucose uptake and glycolysis regardless of oxygen availability. This metabolic shift leads to an enhanced production of lactic acid that decreases extracellular pH (pHe), a hallmark of the tumor microenvironment. In this way, dysregulated tumor pHe and upregulated glucose metabolism are linked tightly and their relative assessment may be useful to gain understanding of the underlying biology. Here we investigated noninvasively the in vivo correlation between tumor 18F-FDG uptake and extracellular pH values in a murine model of HER2+ breast cancer. Tumor extracellular pH and perfusion were assessed by acquiring MRI-CEST (chemical exchange saturation transfer) images on a 3T scanner after intravenous administration of a pH-responsive contrast agent (iopamidol). Static PET images were recorded immediately after MRI acquisitions to quantify the extent of 18F-FDG uptake. We demonstrated the occurrence of tumor pHe changes that report on acidification of the interstitial fluid caused by an accelerated glycolysis. Combined PET and MRI-CEST images reported complementary spatial information of the altered glucose metabolism. Notably, a significant inverse correlation was found between extracellular tumor pH and 18F-FDG uptake, as a high 18F-FDG uptake corresponds to lower extracellular pH values. These results show how merging the information from 18F-FDG-uptake and extracellular pH measurements can improve characterization of the tumor microenvironment. Cancer Res; 76(22); 6463-70. ©2016 AACR.
Serial in vivo spectroscopic nuclear magnetic resonance imaging of lactate and extracellular pH in rat gliomas shows redistribution of protons away from sites of glycolysis. [2013]The acidity of the tumor microenvironment aids tumor growth, and mechanisms causing it are targets for potential therapies. We have imaged extracellular pH (pHe) in C6 cell gliomas in rat brain using 1H magnetic resonance spectroscopy in vivo. We used a new probe molecule, ISUCA [(+/-)2-(imidazol-1-yl)succinic acid], and fast imaging techniques, with spiral acquisition in k-space. We obtained a map of metabolites [136 ms echo time (TE)] and then infused ISUCA in a femoral vein (25 mmol/kg body weight over 110 min) and obtained two consecutive images of pHe within the tumor (40 ms TE, each acquisition taking 25 min). pHe (where ISUCA was present) ranged from 6.5 to 7.5 in voxels of 0.75 microL and did not change detectably when [ISUCA] increased. Infusion of glucose (0.2 mmol/kg.min) decreased tumor pHe by, on average, 0.150 (SE, 0.007; P
Longitudinal Measurements of Intra- and Extracellular pH Gradient in a Rat Model of Glioma. [2019]This study presents the first longitudinal measurement of the intracellular/extracellular pH gradient in a rat glioma model using noninvasive magnetic resonance imaging. The acid-base balance in the brain is tightly controlled by endogenous buffers. Tumors often express a positive pH gradient (pHi - pHe) compared with normal tissue that expresses a negative gradient. Alkaline pHi in tumor cells increases activity of several enzymes that drive cellular proliferation. In contrast, acidic pHe is established because of increased lactic acid production and subsequent active transport of protons out of the cell. pHi was mapped using chemical exchange saturation transfer, whereas regional pHe was determined using hyperpolarized 13C bicarbonate magnetic resonance spectroscopic imaging. pHi and pHe were measured at days 8, 12, and 15 postimplantation of C6 glioma cells into rat brains. Measurements were made in tumors and compared to brain tissue without tumor. Overall, average pH gradient in the tumor changed from -0.02 ± 0.12 to 0.10 ± 0.21 and then 0.19 ± 0.16. Conversely, the pH gradient of contralateral brain tissue changed from -0.45 ± 0.16 to -0.25 ± 0.21 and then -0.34 ± 0.25 (average pH ± 1 SD) Spatial heterogeneity of tumor pH gradient was apparent at later time points and may be useful to predict local areas of treatment resistance. Overall, the intracellular/extracellular pH gradients in this rat glioma model were noninvasively measured to a precision of ∼0.1 pH units at 3 time points. Because most therapeutic agents are weak acids or bases, a priori knowledge of the pH gradient may help guide choice of therapeutic agent for precision medicine.
Quantification of tumor microenvironment acidity in glioblastoma using principal component analysis of dynamic susceptibility contrast enhanced MR imaging. [2021]Glioblastoma (GBM) has high metabolic demands, which can lead to acidification of the tumor microenvironment. We hypothesize that a machine learning model built on temporal principal component analysis (PCA) of dynamic susceptibility contrast-enhanced (DSC) perfusion MRI can be used to estimate tumor acidity in GBM, as estimated by pH-sensitive amine chemical exchange saturation transfer echo-planar imaging (CEST-EPI). We analyzed 78 MRI scans in 32 treatment naïve and post-treatment GBM patients. All patients were imaged with DSC-MRI, and pH-weighting that was quantified from CEST-EPI estimation of the magnetization transfer ratio asymmetry (MTRasym) at 3 ppm. Enhancing tumor (ET), non-enhancing core (NC), and peritumoral T2 hyperintensity (namely, edema, ED) were used to extract principal components (PCs) and to build support vector machines regression (SVR) models to predict MTRasym values using PCs. Our predicted map correlated with MTRasym values with Spearman's r equal to 0.66, 0.47, 0.67, 0.71, in NC, ET, ED, and overall, respectively (p < 0.006). The results of this study demonstrates that PCA analysis of DSC imaging data can provide information about tumor pH in GBM patients, with the strongest association within the peritumoral regions.
Mapping extracellular pH in rat brain gliomas in vivo by 1H magnetic resonance spectroscopic imaging: comparison with maps of metabolites. [2022]The value of extracellular pH (pH(e)) in tumors is an important factor in prognosisand choice of therapy. We demonstrate here that pH(e) can be mappedin vivo in a rat brain glioma by (1)H magnetic resonance spectroscopic imaging (SI) of the pH buffer (+/-)2-imidazole-1-yl-3-ethoxycarbonylpropionic acid (IEPA). (1)H SI also allowed us to map metabolites, and, to better understand the determinants of pH(e), we compared maps of pH(e), metabolites, and the distribution of the contrast agent gadolinium1,4,7,10-tetraazacyclododecane-N,N',N",N"'-tetraaceticacid (Gd-DOTA). C6 cells injected in caudate nuclei of four Wistar rats gave rise to gliomas of approximately 10 mm in diameter. Three mmols of IEPA were injected in the right jugular vein from t = 0 to t = 60 min. From t = 50 min to t = 90 min, spin-echo (1)H SI was performed with an echo time of 40 ms in a 2.5-mm slice including the glioma (nominal voxel size, 2.2 microl). IEPA resonances were detected only within the glioma and were intense enough for pH(e) to be calculated from the chemical shift of the H2 resonance in almost all voxels of the glioma. (1)H spectroscopic images with an echo time of 136 ms were then acquired to map metabolites: lactate, choline-containing compounds (tCho), phosphocreatine/creatine, and N-acetylaspartate. Finally, T(1)-weighted imaging after injection of a bolus of Gd-DOTA gave a map indicative of extravasation. On average, the gradient of pH(e) (measured where sufficient IEPA was present) from the center to the periphery was not statistically significant. Mean pH(e) was calculated for each of the four gliomas, and the average was 7.084 +/- 0.017 (+/- SE; n = 4 rats), which is acid with respect to pH(e) of normal tissue. After normalization of spectra to their water peak, voxel-by-voxel comparisons of peak areas showed that N-acetylaspartate, a marker of neurons, correlated negatively with IEPA (P
Imaging chemical exchange saturation transfer (CEST) effects following tumor-selective acidification using lonidamine. [2015]Increased lactate production through glycolysis in aerobic conditions is a hallmark of cancer. Some anticancer drugs have been designed to exploit elevated glycolysis in cancer cells. For example, lonidamine (LND) inhibits lactate transport, leading to intracellular acidification in cancer cells. Chemical exchange saturation transfer (CEST) is a novel MRI contrast mechanism that is dependent on intracellular pH. Amine and amide concentration-independent detection (AACID) and apparent amide proton transfer (APT*) represent two recently developed CEST contrast parameters that are sensitive to pH. The goal of this study was to compare the sensitivity of AACID and APT* for the detection of tumor-selective acidification after LND injection. Using a 9.4-T MRI scanner, CEST data were acquired in mice approximately 14 days after the implantation of 10(5) U87 human glioblastoma multiforme (GBM) cells in the brain, before and after the administration of LND (dose, 50 or 100 mg/kg). Significant dose-dependent LND-induced changes in the measured CEST parameters were detected in brain regions spatially correlated with implanted tumors. Importantly, no changes were observed in T1- and T2-weighted images acquired before and after LND treatment. The AACID and APT* contrast measured before and after LND injection exhibited similar pH sensitivity. Interestingly, LND-induced contrast maps showed increased heterogeneity compared with pre-injection CEST maps. These results demonstrate that CEST contrast changes after the administration of LND could help to localize brain cancer and monitor tumor response to chemotherapy within 1 h of treatment. The LND CEST experiment uses an anticancer drug to induce a metabolic change detectable by endogenous MRI contrast, and therefore represents a unique cancer detection paradigm which differs from other current molecular imaging techniques that require the injection of an imaging contrast agent or tracer.
[Intracellular pH measurement in glioblastoma cells: the possibilities of phosphorus-31 MR spectroscopy]. [2020]To analyze intracellular pH measurement with phosphorus-31 MR spectroscopy in glioblastoma cells and to compare these data with intracellular pH in healthy volunteers.