Quantification of tumor microenvironment acidity in glioblastoma using principal component analysis of dynamic susceptibility contrast enhanced MR imaging.

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

Timed sequential therapy of the selective T-type calcium channel blocker mibefradil and temozolomide in patients with recurrent high-grade gliomas

Background: Mibefradil (MIB), previously approved for treatment of hypertension, is a selective T-type calcium channel blocker with preclinical activity in high-grade gliomas (HGGs). To exploit its presumed mechanism of impacting cell cycle activity (G1 arrest), we designed a phase I study to determine safety and the maximum tolerated dose (MTD) of MIB when given sequentially with temozolomide (TMZ) in recurrent (r)HGG. Methods: Adult patients with rHGG ≥3 months from TMZ for initial therapy received MIB in 4 daily doses (q.i.d.) for 7 days followed by standard TMZ at 150-200 mg/m2 for 5 days per 28-day cycle. MIB dose escalation followed a modified 3 + 3 design, with an extension cohort of 10 patients at MTD who underwent 3\u27-deoxy-3\u27-18F-fluorothymidine (18F-FLT) PET imaging, to image proliferation before and after 7 days of MIB. Results: Twenty-seven patients were enrolled (20 World Health Organization grade IV, 7 grade III; median age 50 y; median KPS 90). The MTD of MIB was 87.5 mg p.o. q.i.d. Dose-limiting toxicities were elevation of alanine aminotransferase/aspartate aminotransferase (grade 3) and sinus bradycardia. The steady-state maximum plasma concentration of MIB at the MTD was 1693 ± 287 ng/mL (mean ± SD). 18F-FLT PET imaging showed a significant decline in standardized uptake value (SUV) signal in 2 of 10 patients after 7 days of treatment with MIB. Conclusions: MIB followed by TMZ was well tolerated in rHGG patients at the MTD. The lack of toxicity and presence of some responses in this selected patient population suggest that this regimen warrants further investigation

Multiparametric magnetic resonance imaging in the assessment of anti-EGFRvIII chimeric antigen receptor T cell therapy in patients with recurrent glioblastoma

EGFRvIII targeted chimeric antigen receptor T (CAR-T) cell therapy has recently been reported for treating glioblastomas (GBMs); however, physiology-based MRI parameters have not been evaluated in this setting. Ten patients underwent multiparametric MRI at baseline, 1, 2 and 3 months after CAR-T therapy. Logistic regression model derived progression probabilities (PP) using imaging parameters were used to assess treatment response. Four lesions from “early surgery” group demonstrated high PP at baseline suggestive of progression, which was confirmed histologically. Out of eight lesions from remaining six patients, three lesions with low PP at baseline remained stable. Two lesions with high PP at baseline were associated with large decreases in PP reflecting treatment response, whereas other two lesions with high PP at baseline continued to demonstrate progression. One patient didn’t have baseline data but demonstrated progression on follow-up. Our findings indicate that multiparametric MRI may be helpful in monitoring CAR-T related early therapeutic changes in GBM patients

Menstrual Hygiene Practices, WASH Access and the Risk of Urogenital Infection in Women from Odisha, India: Supporting Information

Dataset and other information published to support a PLOS publication on menstrual hygiene practices, WASH access and the risk of urogenital Infection in women from Odisha, Indi