Vitamin E Derivative with Modified Side Chain Induced Apoptosis by Modulating the Cellular Lipids and Membrane Dynamics in MCF7 Cells.

The vitamin E derivative with side chain modification (TC6OAc) has been shown to possess anticancer activity in our earlier in vivo studies. It was hypothesized that, as Vitamin E (VE) and VE derivative are fat soluble lipophilic molecules, they exert their function by modulating the lipid metabolism and related pathways. This study aimed to evaluate the cellular impact of this VE derivative (2,5,7,8-Tetramethyl-2-(4'-Methyl-3'-Pentenyl)-6-Acetoxy Chromane-TC6OH), using α-tocopherol as a reference compound throughout the experiments. Their effects on the cellular metabolism, the biophysical properties of cellular lipids and the functional characteristics of cells were monitored in human estrogen receptor (ER) positive breast cancer cells. It has been documented that TC6OH treatment induces tumor cell apoptosis by dissipating the mitochondrial membrane potential, modulating the lipid, transportation and degradation as well as downregulating certain anti-apoptotic and growth factor related proteins. Due to resistance of ER positive cells to the established therapies, the findings of this study are of translational value.

Valdecoxib Recovers the Lipid Composition, Order and Dynamics in Colon Cancer Cell Lines Independent of COX-2 Expression: An ATR-FTIR Spectroscopy Study.

Prostanoids play an important role in a variety of physiological and pathophysiological processes including inflammation and cancer. The rate-limiting step in the prostanoid biosynthesis pathway is catalyzed by cyclooxygenases (COXs). Aberrant expression of the inducible isoform COX-2 plays a significant role in colon cancer initiation and progression. In this study, we have hypothesized that COX-2 specific inhibitors such as Valdecoxib (VLX), being highly hydrophobic, may alter biophysical properties of cellular lipids. In this study, COX-2 expressing (HT29) and COX-2 non-expressing (SW620) colon cancer cell lines were treated with VLX and examined using attenuated total reflection infrared spectroscopy. The results revealed that VLX treatment decreased lipid fluidity in the cells irrespective of COX-2 expression status and affected order parameters of the lipids in both cell lines. Cluster analysis also indicated that the spectral differences between the two cell lines are profound and could be successfully differentiated. Valdecoxib treatment could enhance the composition, order and dynamics of the lipids of colon cancer cells independently of its COX-2 inhibitory mechanism. Valdecoxib has therapeutic effects upon colon cancer, therefore it can be used as an adjuvant and/or chemopreventive agent for colon cancer.

Bladder cancer diagnosis from bladder wash by Fourier transform infrared spectroscopy as a novel test for tumor recurrence.

This study proposes Fourier Transform Infrared (FTIR) spectroscopy as a more sensitive, rapid, non-destructive and operator-independent analytical diagnostic method for bladder cancer recurrence from bladder wash than other routinely used urine cytology and cystoscopy methods. A total of 136 patients were recruited. FTIR spectroscopic experiments were carried out as a blind study, the classification results of which were then compared with those of cytology and cystoscopy. Firstly, 71 samples (n = 37; bladder cancer and n = 34; control) were studied with transmittance FTIR spectroscopy. After achieving successful differentiation of the groups, to develop a more rapid diagnostic tool and check the reproducibility of the results, the work was continued with different samples (n = 65 as n = 44; bladder cancer and n = 21; control), using the reflection mode (ATR) of FTIR spectroscopy by a different operator. The results revealed significant alterations in moleculer content in the cancer group. Based on the spectral differences, using transmittance FTIR spectroscopy coupled with chemometrics, the diseased group was successfully differentiated from the control. When only carcinoma group was taken into consideration a sensitivity value of 100% was achieved. Similar results were also obtained by ATR-FTIR spectroscopy. This study shows the power of infrared spectroscopy in the diagnosis of bladder cancer.

Differentiation of Anatolian honey samples from different botanical origins by ATR-FTIR spectroscopy using multivariate analysis.

Botanical origin of the nectar predominantly affects the chemical composition of honey. Analytical techniques used for reliable honey authentication are mostly time consuming and expensive. Additionally, they cannot provide 100% efficiency in accurate authentication. Therefore, alternatives for the determination of floral origin of honey need to be developed. This study aims to discriminate characteristic Anatolian honey samples from different botanical origins based on the differences in their molecular content, rather than giving numerical information about the constituents of samples. Another scope of the study is to differentiate inauthentic honey samples from the natural ones precisely. All samples were tested via unsupervised pattern recognition procedures like hierarchical clustering and Principal Component Analysis (PCA). Discrimination of sample groups was achieved successfully with hierarchical clustering over the spectral range of 1800-750 cm(-1) which suggests a good predictive capability of Fourier Transform Infrared (FTIR) spectroscopy and chemometry for the determination of honey floral source.

Concentration-based measurement studies of L-tryptophan using terahertz time-domain spectroscopy (THz-TDS).

L-Tryptophan is an extremely important amino acid for a variety of biological functions in living organisms. In this study we were able to measure changes in the concentration of L-tryptophan when incorporated into pellets with polyethylene as a host. The changes were measured both through the characteristic absorption bands of the C11 and C12 bonds in the low terahertz frequency range and using changes in the refractive index where pellets with higher concentrations of L-tryptophan showed higher refractive indices. The volumetric concentration of L-tryptophan in the polyethylene pellet was accurately determined with a simple model that explains the contribution to the complex refractive index for the resultant sample due to the two constituent materials. These measurements show that terahertz time-domain techniques can be applied to detect variation in concentration of certain amino acids rapidly by examining the relative phase delay and amplitude change of the terahertz transients.