scholarly journals Ex vivo ultrasonic samples of human brain tumors in the molecular era

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Alastair J Kirby ◽  
José P Lavrador ◽  
Istvan Bodi ◽  
Francesco Vergani ◽  
Ranjeev Bhangoo ◽  
...  
Keyword(s):  
Dna Methyltransferase ◽  
Cellular Proliferation ◽  
Aminolevulinic Acid ◽  
Ex Vivo ◽  
Methylation Status ◽  
Protoporphyrin Ix ◽  
Intratumor Heterogeneity ◽  
Power Relationship ◽  
Surgical Biopsy ◽  
Glioma Surgery

Abstract Background Gliomas are composed of multiple clones of tumor cells. This intratumor heterogeneity contributes to the ability of gliomas to resist treatment. It is vital that gliomas are fully characterized at a molecular level when a diagnosis is made to maximize treatment effectiveness. Methods We collected ultrasonic tissue fragments during glioma surgery. Large tissue fragments were separated in the operating theater and bathed continuously in oxygenated artificial cerebrospinal fluid to keep them alive. The ex vivo tissue fragments were transferred to a laboratory and incubated in 5-aminolevulinic acid (5-ALA). 5-ALA is metabolized to Protoporphyrin IX (PpIX), which accumulates in glioma cells and makes them fluorescent. The molecular and neuropathological features of the PpIX fluorescent ultrasonic tissue fragments were studied. Results We show that PpIX fluorescence can rapidly identify tissue fragments infiltrated by glioma in the laboratory. Ultrasonic tissue fragments from the tumor core provided molecular and neuropathological information about the glioma that was comparable to the surgical biopsy. We characterized the heterogeneity within individual gliomas by studying ultrasonic tissue fragments from different parts of the tumor. We found that gliomas exhibit a power relationship between cellular proliferation and tumor infiltration. Tissue fragments that deviate from this relationship may contain foci of more malignant glioma. The methylation status of the O6-methylguanine DNA methyltransferase gene promoter varied within each glioma. Conclusions Ex vivo ultrasonic tissue fragments can be rapidly screened for glioma infiltration. They offer a viable platform to characterize heterogeneity within individual gliomas, thereby enhancing their diagnosis and treatment.

Influence of dexamethasone on visible 5-ALA fluorescence and quantitative protoporphyrin IX accumulation measured by fluorescence lifetime imaging in glioblastomas: is pretreatment obligatory before fluorescence-guided surgery?

2021 ◽  
pp. 1-9
Author(s):  
Lisa I. Wadiura ◽  
David Reichert ◽  
Veronika Sperl ◽  
Alexandra Lang ◽  
Barbara Kiesel ◽  
...  
Keyword(s):  
Fluorescence Lifetime ◽  
Aminolevulinic Acid ◽  
Ex Vivo ◽  
Protoporphyrin Ix ◽  
Fluorescence Lifetime Imaging ◽  
Lifetime Imaging ◽  
Guided Surgery ◽  
Fluorescence Guided Surgery ◽  
Significant Difference ◽  
The Mean

OBJECTIVE Fluorescence-guided surgery using 5-aminolevulinic acid (5-ALA) is nowadays widely applied for improved resection of glioblastomas (GBMs). Initially, pretreatment with dexamethasone was considered to be essential for optimal fluorescence effect. However, recent studies reported comparably high rates of visible fluorescence in GBMs despite absence of dexamethasone pretreatment. Recently, the authors proposed fluorescence lifetime imaging (FLIM) for the quantitative analysis of 5-ALA–induced protoporphyrin IX (PpIX) accumulation. The aim of this study was thus to investigate the influence of dexamethasone on visible fluorescence and quantitative PpIX accumulation. METHODS The authors prospectively analyzed the presence of visible fluorescence during surgery in a cohort of patients with GBMs. In this study, patients received dexamethasone preoperatively only if clinically indicated. One representative tumor sample was collected from each GBM, and PpIX accumulation was analyzed ex vivo by FLIM. The visible fluorescence status and mean FLIM values were correlated with preoperative intake of dexamethasone. RESULTS In total, two subgroups with (n = 27) and without (n = 20) pretreatment with dexamethasone were analyzed. All patients showed visible fluorescence independent from preoperative dexamethasone intake. Furthermore, the authors did not find a statistically significant difference in the mean FLIM values between patients with and without dexamethasone pretreatment (p = 0.097). CONCLUSIONS In this first study to date, the authors found no significant influence of dexamethasone pretreatment on either visible 5-ALA fluorescence during GBM surgery or PpIX accumulation based on FLIM. According to these preliminary data, the authors recommend administering dexamethasone prior to fluorescence-guided surgery of GBMs only when clinically indicated.

In vitro and ex vivo protoporphyrin IX expression induced by 5-aminolevulinic acid in human pilosebaceous unit

2005 ◽  
Vol 40 (1) ◽  
pp. 68-70 ◽  
Author(s):  
Mee Sook Jun ◽  
Hyo-Seon Choi ◽  
Insook Han ◽  
Moonkyu Kim ◽  
Jung Chul Kim
Keyword(s):  
Aminolevulinic Acid ◽  
Ex Vivo ◽  
Protoporphyrin Ix ◽  
Pilosebaceous Unit

scholarly journals Epidermal penetration and protoporphyrin IX formation of two different 5-aminolevulinic acid formulations in ex vivo human skin

2016 ◽  
Vol 14 ◽  
pp. 40-46 ◽  
Author(s):  
Lutz Schmitz ◽  
Ben Novak ◽  
Ann-Kathrin Hoeh ◽  
Herman Luebbert ◽  
Thomas Dirschka
Keyword(s):  
Human Skin ◽  
Aminolevulinic Acid ◽  
Ex Vivo ◽  
Protoporphyrin Ix

scholarly journals Characterization of autofluorescence and quantitative protoporphyrin IX biomarkers for optical spectroscopy-guided glioma surgery

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
David Black ◽  
Sadahiro Kaneko ◽  
Anna Walke ◽  
Simone König ◽  
Walter Stummer ◽  
...  
Keyword(s):  
Aminolevulinic Acid ◽  
Protoporphyrin Ix ◽  
Blue Shift ◽  
Spectral Unmixing ◽  
Proliferation Index ◽  
Low Grade ◽  
Glioma Surgery ◽  
Ki 67 ◽  
Who Grade

Abstract5-Aminolevulinic acid (5-ALA)-mediated fluorescence does not effectively depict low grade gliomas (LGG) or the infiltrative tumor portion of high-grade gliomas (HGG). While spectroscopy improves sensitivity and precision, this is currently limited by autofluorescence and a second protoporphyrin IX (PpIX) fluorescence state at 620 nm. We investigated the autofluorescence to better characterize the present spectra and thus increase PpIX quantification precision and sensitivity. This study included 128 patients undergoing surgery for malignant glioma. 5-ALA (Gliolan) was administered before anesthesia, and fluorescence was measured using a hyperspectral device. It was found that all 2692 measured spectra consisted of contributions from 620 to 634 nm PpIX, NADH, lipofuscin, and flavins. The basis spectra were characterized and their use in spectral unmixing led to 82.4% lower fitting error for weakly fluorescing areas (p < 0.001), and 92.3% fewer false positive tumor identifications in control measurements (p = 0.0065) compared to previous works. They also decreased the PpIX620 contribution, thus halving the mean Ratio620/634 (p < 0.001). The ratio was approximately 0 for HGGs and increasing for LGGs, as demonstrated previously. Additionally, the Ratio620/634, the MIB-1/Ki-67 proliferation index, and the PpIX peak blue-shift were found to be significantly related to WHO grade, fluorescence visibility, and PpIX contribution (p < 0.001), and the value of these three as quantitative biomarkers is discussed.

scholarly journals Lack of effect of selected sunscreens applied on ex vivo human skin for 5-methyl-aminolevulinic acid penetration and protoporphyrin IX photoactivation

2017 ◽  
Vol 17 ◽  
pp. 75-81 ◽  
Author(s):  
Hanan Osman-Ponchet ◽  
Karine Sevin ◽  
Alexandre Gaborit ◽  
Magali Kouidhi ◽  
Johanna Hanaizi ◽  
...  
Keyword(s):  
Human Skin ◽  
Aminolevulinic Acid ◽  
Ex Vivo ◽  
Protoporphyrin Ix

Role of the IL-6 Pathway in Multiple Myeloma Cell Growth and Its Implications in Target Gene Hypermethylation.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 4769-4769
Author(s):  
Susan B. Ingersoll ◽  
Natalie D. Thoni ◽  
Farhana Ahmed ◽  
Kimberly A. Monahan ◽  
Lizette Caballero ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Cell Growth ◽  
Cell Lines ◽  
Dna Methyltransferase ◽  
Cellular Proliferation ◽  
Methylation Status ◽  
Myeloma Cell ◽  
Chemotherapeutic Agents ◽  
Aberrant Methylation ◽  
Multiple Myeloma Cell

Abstract Aberrant methylation of promoter regions of tumor suppressor genes (TSG) has recently become recognized as an important epigenetic event in cancer and tumor progression including multiple myeloma. Interleukin-6 (IL-6), which is known to play a significant role in the pathophysiology of myeloma, regulates DNA methylation by inducing expression of FLI-1, a transcription factor of DNA methyltransferase-1 (DNMT-1), resulting in over-expression of DNMT-1 and thus hypermethylation of TSG. Despite this understanding, attempts to bring IL-6 blockade to the clinic have had limited success. We hypothesize that IL-6 regulation of epigenetic events (hypermethylation) may be an important pathway that could eventually allow rational chemotherapeutic/anit-IL-6 combinations. We have studied the correlation of IL-6 expression and dependence in myeloma cell lines and correlated that to the methylation profile of TSG, DcR1 and CDH1. Using three well-established multiple myeloma cell lines: U266B1 (U266), RPMI 8226 (RPMI), and KAS6/1 (KAS), we have confirmed that KAS is IL-6-dependent (exogenous IL-6 is needed) whereas the U266 and RPMI are IL-6 independent. To determine if blockade of the IL-6 pathway would inhibit the growth of the myeloma cell lines, these cells were grown in the presence of an anti-IL-6 antibody (B-E8; Cell Sciences, Canton, MA) that is known to block IL-6 signaling in the cells. We found that blocking IL-6 (by B-E8, 200 ng/ml) inhibited the growth of U266 (36% inhibition; n≥3, p<0.01) and KAS (68% inhibition; n≥3, p<0.001) cells, but not RPMI cells. We examined IL-6 expression in these three cell lines by RT-PCR and found that U266 expresses IL-6 mRNA, but RPMI and KAS cells do not. This IL-6 mRNA expression pattern correlates well with the anti-IL-6 cellular proliferation findings. Since RPMI is not dependent on the addition of exogenous IL-6 and blocking the IL-6 pathway had no effect on cell growth; therefore, we would not expect the cells to express IL-6. The U266 cells are not dependent on exogenous IL-6 but cellular proliferation can be blocked with an anti-IL-6 antibody; therefore, we expected that the cells would endogenously express IL-6. Furthermore, KAS cells are dependent on exogenous IL-6 and cell growth can be inhibited by anti-IL-6 antibody; therefore, we would not expect the cells to express IL-6. To determine if IL-6 sensitivity correlated with hypermethylation of TSG, we investigated the methylation status of the DcR1(tumor necrosis factor-related apoptosis inducing ligand decoy receptor 1) and CDH1 (Cadherin 1) loci. We have shown that CDH1 is methylated in U266 cells and un-methylated in RPMI cells. Experiments are underway to determine the methylation status in KAS cells and gene expression in all cell-lines for CDH1. Finally, we found that the RPMI and KAS cells are un-methylated and U266 cells are methylated at the DcR1 locus. We have found that in the RPMI and U266 cell lines that methylation of target TSG correlates with anti-IL-6 sensitivity. These data support our hypothesis that an IL-6-dependent pathway may regulate hypermethylation of important TSG in multiple myeloma. Newer chemotherapeutic agents that may affect methylation pathways are being studied in combination with IL-6 blockade.

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