Apoptosis is associated with triacylglycerol accumulation in Jurkat T-cells

Magnetic resonance spectroscopy is increasingly used as a non-invasive method to investigate apoptosis. Apoptosis was induced in Jurkat T-cells by Fas mAb. 1H magnetic resonance spectra of live cells showed an increase in methylene signal as well as methylene/methyl ratio of fatty acid side chains at 5 and 24 h following induction of apoptosis. To explain this observation, 1H magnetic resonance spectra of cell extracts were investigated. These demonstrated a 70.0±7.0%, 114.0±8.0% and 90.0±5.0% increase in the concentration of triacylglycerols following 3, 5 and 7 h of Fas mAb treatment (P<0.05). Confocal microscopy images of cells stained with the lipophilic dye Nile Red demonstrated the presence of lipid droplets in the cell cytoplasm. Quantification of the stained lipids by flow cytometry showed a good correlation with the magnetic resonance results (P⩾0.05 at 3, 5 and 7 h). 31P magnetic resonance spectra showed a drop in phosphatidylcholine content of apoptosing cells, indicating that alteration in phosphatidylcholine metabolism could be the source of triacylglycerol accumulation during apoptosis. In summary, apoptosis is associated with an early accumulation of mobile triacylglycerols mostly in the form of cytoplasmic lipid droplets. This is reflected in an increase in the methylene/methyl ratio which could be detected by magnetic resonance spectroscopy

Use of neoadjuvant chemotherapy prior to radical hysterectomy in cervical cancer: monitoring tumour shrinkage and molecular profile on magnetic resonance and assessment of 3-year outcome

Use of neoadjuvant chemotherapy prior to radical hysterectomy in cervical cancer: monitoring tumour shrinkage and molecular profile on magnetic resonance and assessment of 3-year outcome The objective of this study is to assess tumour response to neoadjuvant chemotherapy prior to radical hysterectomy in cervical cancer using magnetic resonance (MR) to monitor tumour volume and changes in molecular profile and to compare the survival to that of a control group. Eligibility included Stage Ib-IIb previously untreated cervical tumours >10 cm(3). Neoadjuvant chemotherapy in 22 patients ( methotrexate 300 mg m(-2) (with folinic acid rescue), bleomycin 30 mg m(-2), cisplatin 60 mg m(-2)) was repeated twice weekly for three courses and followed by radical hysterectomy. Post-operative radiotherapy was given in 14 cases. A total of 23 patients treated either with radical surgery or chemoradiotherapy over the same time period comprised the nonrandomised control group. MR scans before and after neoadjuvant chemotherapy and in the control group documented tumour volume on imaging and metabolites on in vivo spectroscopy. Changes were compared using a paired t-test. Survival was calculated using the Kaplan-Meier method. There were no significant differences between the neoadjuvant chemotherapy and control groups in age ( mean, s.d. 43.3 +/- 10, 44.7 +/- 8.5 years, respectively, P = 0.63) or tumour volume (medians, quartiles 35.8, 17.8, 57.7 cm(3) vs 23.0, 15.0, 37.0 cm(3), respectively, P = 0.068). The reduction in tumour volume post-chemotherapy (median, quartiles 7.5, 3.0, 19.0 cm(3)) was significant ( P = 0.002). The reduction in - CH2 triglyceride approached significance ( P = 0.05), but other metabolites were unchanged. The 3-year survival in the chemotherapy group (49.1%) was not significantly different from the control group (46%, P = 0.94). There is a significant reduction in tumour volume and - CH2 triglyceride levels after neoadjuvant chemotherapy, but there is no survival advantage

Taurine: a potential marker of apoptosis in gliomas

New cancer therapies are being developed that trigger tumour apoptosis and an in vivo method of apoptotic detection and early treatment response would be of great value. Magnetic resonance spectroscopy (MRS) can determine the tumour biochemical profile in vivo, and we have investigated whether a specific spectroscopic signature exists for apoptosis in human astrocytomas. High-resolution magic angle spinning (HRMAS) 1H MRS provided detailed 1H spectra of brain tumour biopsies for direct correlation with histopathology. Metabolites, mobile lipids and macromolecules were quantified from presaturation HRMAS 1H spectra acquired from 41 biopsies of grades II (n=8), III (n=3) and IV (n=30) astrocytomas. Subsequently, TUNEL and H&E staining provided quantification of apoptosis, cell density and necrosis. Taurine was found to significantly correlate with apoptotic cell density (TUNEL) in both non-necrotic (R=0.727, P=0.003) and necrotic (R=0.626, P=0.0005) biopsies. However, the ca 2.8 p.p.m. polyunsaturated fatty acid peak, observed in other studies as a marker of apoptosis, correlated only in non-necrotic biopsies (R=0.705, P<0.005). We suggest that the taurine 1H MRS signal in astrocytomas may be a robust apoptotic biomarker that is independent of tumour necrotic status

3D extracellular matrix microenvironment in bioengineered tissue models of primary pediatric and adult brain tumors.

Dynamic alterations in the unique brain extracellular matrix (ECM) are involved in malignant brain tumors. Yet studies of brain ECM roles in tumor cell behavior have been difficult due to lack of access to the human brain. We present a tunable 3D bioengineered brain tissue platform by integrating microenvironmental cues of native brain-derived ECMs and live imaging to systematically evaluate patient-derived brain tumor responses. Using pediatric ependymoma and adult glioblastoma as examples, the 3D brain ECM-containing microenvironment with a balance of cell-cell and cell-matrix interactions supports distinctive phenotypes associated with tumor type-specific and ECM-dependent patterns in the tumor cells\u27 transcriptomic and release profiles. Label-free metabolic imaging of the composite model structure identifies metabolically distinct sub-populations within a tumor type and captures extracellular lipid-containing droplets with potential implications in drug response. The versatile bioengineered 3D tumor tissue system sets the stage for mechanistic studies deciphering microenvironmental role in brain tumor progression

Inhibition of Pediatric Glioblastoma Tumor Growth by the Anti-Cancer Agent OKN-007 in Orthotopic Mouse Xenografts

We thank the Peggy and Charles Stephenson Cancer Center at the University of Oklahoma, Oklahoma City, OK, for funding, who received an Institutional Development Award (IDeA) from the National Institute of General Medical Sciences of the National Institutes of Health under grant number P20 GM103639 for the use of the Histology and Immunohistochemistry Core for providing immunohistochemistry and photographic services. This work was also supported by Oklahoma State University, Center of Veterinary Health Science (Support Grant AE-1-50060 to P.C.S.), the Musella Foundation (R.A.T.), and the Childhood Brain Tumor Foundation (R.A.T.).Pediatric glioblastomas (pGBM), although rare, are one of the leading causes of cancer-related deaths in children, with tumors essentially refractory to existing treatments. Here, we describe the use of conventional and advanced in vivo magnetic resonance imaging (MRI) techniques to assess a novel orthotopic xenograft pGBM mouse (IC-3752GBM patient-derived culture) model, and to monitor the effects of the anti-cancer agent OKN-007 as an inhibitor of pGBM tumor growth. Immunohistochemistry support data is also presented for cell proliferation and tumor growth signaling. OKN-007 was found to significantly decrease tumor volumes (p<0.05) and increase animal survival (p<0.05) in all OKN-007-treated mice compared to untreated animals. In a responsive cohort of treated animals, OKN-007 was able to significantly decrease tumor volumes (p<0.0001), increase survival (p<0.001), and increase diffusion (p<0.01) and perfusion rates (p<0.05). OKN-007 also significantly reduced lipid tumor metabolism in responsive animals (Lip1.3 and Lip0.9)-to-creatine ratio (p<0.05), as well as significantly decrease tumor cell proliferation (p<0.05) and microvessel density (p<0.05). Furthermore, in relationship to the PDGFRα pathway, OKN-007 was able to significantly decrease SULF2 (p<0.05) and PDGFR-α (platelet-derived growth factor receptor-α) (p<0.05) immunoexpression, and significantly increase decorin expression (p<0.05) in responsive mice. This study indicates that OKN-007 may be an effective anti-cancer agent for some patients with pGBMs by inhibiting cell proliferation and angiogenesis, possibly via the PDGFRα pathway, and could be considered as an additional therapy for pediatric brain tumor patients.Yeshttp://www.plosone.org/static/editorial#pee

The effect of altering time domains and window functions in two-dimensional proton COSY spectra of biological specimens

The time constraints imposed by the limited viability of biopsy and cell samples require careful selection of both acquisition and processing parameters for two-dimensional NMR spectroscopy. The consequences of truncating 2D NMR data sets in the t1 dimension are discussed in terms of the inherent loss of resolution versus the time constraints imposed by the degrading sample. The choice of window functions during processing is shown to have dramatic effects on the resolution, sensitivity, and appearance of 2D spectra of biological specimens containing lipid. For magnitude-mode COSY spectra, sine-bell window functions in both domains generally give the best combination of resolution, lineshape, and signal-to-noise. However, components with short spin-spin relaxation values (including lipid and oligopeptides) are better visualized by applying Lorentz-Gauss window functions or by shortening the time domain. This is demonstrated with an example of a 2D data set of cultured malignant melanoma cells processed under various conditions. Each cell line and tissue type (and the molecules of interest) must be considered independently when acquiring, analyzing, and presenting 2D NMR spectra

Human cancers detected by proton MRS and chemical shift imaging ex vivo

Proton magnetic resonance spectroscopy (H-1 MRS) has the potential to become a diagnostic adjunct for the detection and grading of human neoplastic disease. This paper describes the use of proton MRS to document changes arising in the lipid chemistry of biopsies arising from the human uterine cervix, thyroid and colon and demonstrates the diagnostic power of ex vivo spectroscopy. Proton chemical shift imaging (CSI) is further used to determine the spatial location of lipid changes in ex vivo human biopsy specimens and provides insight into the chemistry of neoplastic transformation

Cell-surface fucosylation and magnetic resonance spectroscopy characterization of human malignant colorectal cells

Proton (1H) magnetic resonance spectroscopy (MRS) has been used to distinguish lowly and highly tumorigenic human malignant colorectal cell lines based on differences in lipid, choline, and fucose resonances. The spectral patterns were comparable with those obtained for human colorectal biopsy specimens, indicating that cells grown in vitro are suitable for documenting colorectal tumor biology. For the first time, two-dimensional (2D) correlation spectroscopy (COSY) has been used to assess the fucosylation state on the surface of intact viable cells, and differences were recorded between the highly and lowly tumorigenic cell lines. Four methyl-methine cross-peaks were assigned to covalently linked fucose on the basis of increases in volume following the addition of free fucose. Both cell lines incorporated the same amount of exogenous free fucose as determined chemically, but the COSY spectra indicated that the fucose was distributed differently by each cell line. Of the four sites containing MR-visible bound fucose, one was common to both cell lines, two characteristic of the highly tumorigenic line, and the remaining site unique to the lowly tumorigenic cells. Material released from the highly tumorigenic cells in response to increased cell density was also fucosylated (whereas shed material from lowly tumorigenic cells was not), suggesting a biological role for shed fucosylated antigens in tumor aggression