Association of Glioma Grading With Inflow-Based Vascular-Space-Occupancy MRI: A Preliminary Study at 3T.

BACKGROUND: Inflow-based vascular-space-occupancy (iVASO) MRI is a noninvasive perfusion technique that does not require administration of exogenous contrast agents. Arteriolar cerebral blood volume (CBVa) obtained from iVASO MRI is hypothesized to be an indicator of tumor microvasculature. PURPOSE: To assess the diagnostic performance of iVASO MRI implemented at 3T in predicting histologic grades of cerebral gliomas. STUDY TYPE: Retrospective. SUBJECTS: Forty-five patients (31 males) consisting of 14 WHO grade IV glioblastoma multiformes, 14 grade III, and 17 grade II gliomas. FIELD STRENGTH/SEQUENCE: At 3T we acquired CBVa data using an iVASO sequence. ASSESSMENT: The maximum and mean CBVa (CBVa_max and CBVa_mean) values were calculated in the tumor and normalized to the contralateral thalamus (nCBVa_max and nCBVa_mean). STATISTICAL TESTS: Kruskal-Wallis test, Mann-Whitney test, and receiver operating characteristics (ROC) curve were used for statistical analysis. RESULTS: Both CBVa_max and nCBVa_max increased with tumor grade (P < 0.001). Grade II gliomas showed CBVa_max <0.78 ml / 100 ml in 10/17 cases and nCBVa_max <1.20 in 11/17 cases. Grade III gliomas showed both CBVa_max >0.78 ml / 100 ml and nCBVa_max >1.20 in 13/14 cases, and CBVa_max <2.06 ml / 100 ml in 13/14 cases and nCBVa_max <2.33 in 11/14 cases. Grade IV gliomas showed CBVa_max >2.06 ml / 100 ml in 9/14 cases and nCBVa_max >2.33 in 13/14 cases. The areas under the ROC curve, sensitivity, and specificity were 0.839 (P < 0.001), 92.9% (26/28), and 64.7% (11/17) for CBVa_max, and 0.883 (P < 0.001), 92.9% (26/28), and 70.6% (12/17) for nCBVa_max in the discrimination between grade II and high-grade (grade III and grade IV) tumors, respectively. DATA CONCLUSION: iVASO MRI might be used to help determine and predict glioma grade. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2019;50:1817-1823.

Use of T1 relaxation time in rotating frame (T1 ρ) and apparent diffusion coefficient to estimate cerebral stroke evolution.

BACKGROUND: The major factor for the appropriate treatment strategies for ischemia patients is its onset timing. PURPOSE/HYPOTHESIS: To study to evaluate the diagnostic accuracy of T1 relaxation time in a rotating frame (T1 ρ) and apparent diffusion coefficient (ADC) from MRI to estimate ischemia stages. STUDY TYPE: Prospective. POPULATION/SUBJECTS/PHANTOM/SPECIMEN/ANIMAL MODEL: In all, 73 patients (49 males, aged 29-78 years and 24 females, aged 22-94 years) with ischemia were prospectively imaged with T1 ρ and diffusion MRI during the postischemic period. FIELD STRENGTH/SEQUENCE: 3T/T1 ρ and diffusion-weighted imaging (DWI). ASSESSMENT: Ischemic parenchyma included tissue with elevated signal areas on DWI and correlative hypointense areas on ADC maps. STATISTICAL TESTS: The sensitivity of variables to ischemia time was quantified by analyzing the respective correlations of these values with onset time. RESULTS: ΔT1 ρ (ipsilateral-contralateral differences in T1 ρ) (R2 = 0.956) and T1 ρipsi (ipsilateral ischemia T1 ρ values) (R2 = 0.941) were elevated in all ischemic lesions; these values increased linearly as a function of time, unlike ΔADC (ipsilateral-contralateral differences in ADC) (R2 = -0.410) and ADCipsi (ipsilateral ischemia ADC values) (R2 = 0.550). ΔT1 ρ and T1 ρipsi were significantly different between all stages (P < 0.01), except the acute and hyperacute stages (P = 0.589 for ΔT1 ρ, P = 0.290 for T1 ρipsi , respectively), but ΔADC and ADCipsi only between the late subacute and early subacute stages (P < 0.01) and the late subacute and chronic stages (P < 0.01). DATA CONCLUSION: These data suggest that T1 ρ can provide estimates for the ischemic time in patients. T1 ρ has the potential to outperform diffusion for single-timepoint examination because the T1 ρ change during strokes is positive and linear. If patients with suspected stroke are scanned by MRI within the appropriate timeframe, T1 ρ may provide tools for evaluating stroke onset, potentially aiding in treatment strategies. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;47:1247-1254.

Overexpression of LIMD2 promotes the progression of non-small cell lung cancer.

LIM domain containing 2 (LIMD2) is a small LIM-only protein that has been demonstrated to promote tumor progression; however, the expression and function of LIMD2 in non-small cell lung cancer (NSCLC) has not previously been reported. In the present study, reverse transcription-quantitative PCR and western blot analysis were conducted to examine the mRNA and protein expression levels of LIMD2. Cell Counting Kit-8, Transwell and wound-healing assays were performed in order to examine cell proliferation, invasion and migration, respectively. The data revealed that the LIMD2 expression levels were significantly increased in NSCLC tissues and cell lines, compared with adjacent non-tumor tissues and normal lung epithelial cells, respectively. In addition, the high expression of LIMD2 was significantly associated with lymph node metastasis, distant metastasis and advanced clinical stage in NSCLC. The patients with NSCLC with a high expression of LIMD2 exhibited shorter survival times than those with low LIMD2 expression. The knockdown of LIMD2 caused remarkable decreases in NSCLC cell proliferation, migration and invasion. Bioinformatics analysis and luciferase reporter gene assay data further confirmed that LIMD2 was a direct target gene of microRNA-124 (miR-124), a well-known tumor suppressor in NSCLC. The expression of LIMD2 was negatively regulated by miR-124 in NSCLC cells. In addition, miR-124 was downregulated in NSCLC tissues compared with adjacent non-tumor tissues, and an inverse correlation was observed between the expression of LIMD2 and miR-124 in NSCLC tissues. In conclusion, the present study demonstrates that LIMD2 serves an oncogenic role in NSCLC, suggesting that it may be used as a potential therapeutic target for the treatment of NSCLC.