Identification of dysregulated competing endogenous RNA networks in glioblastoma: A way toward improved therapeutic opportunities

Glioblastoma is recognized as one of the leading causes of death worldwide. Although there have been considerable advancements in understanding the causative molecular mechanisms of this malignancy, effective therapeutic strategies are still in limited use. It has been revealed that non-coding RNAs (ncRNAs) play critical roles in glioblastoma development, while interactions between the regulatory molecules such as long ncRNAs (lncRNAs), microRNAs (miRNAs), transcribed pseudogenes, and circular RNAs (circRNAs) remain to be fully deciphered. Over the recent years, researchers have discovered a new category of RNA molecules called competing endogenous RNA (ceRNA). This kind of RNA can contribute to molecular interactions in the form of ceRNA networks (ceRNETs). Multiple lines of evidence have demonstrated that dysregulation of various ceRNA networks is involved in glioblastoma development. Therefore, gaining insights into these dysregulations might offer potential for the early diagnosis of glioblastoma patients and identification of efficient therapeutic targets. In this review, we provide an overview of recent discoveries on ceRNA networks and the involvement of dysregulated networks in posing limitations to temozolomide therapy. We also describe signaling pathways relevant to the progression of glioblastoma.

Detection of Nicotine Effect on Colon Cells in a Plasmonic Platform

Introduction: Smoking as one of the causes of various diseases has encouraged worldwide studies on its adverse pharmacological effects on different organs. Nicotine may influence the smooth muscles of the colon and subsequently the gut motility, which leads to a change in the moving rate of digested material through the gastrointestinal tract. Methods: Among various techniques, optical detection methods benefit from non-contact and highsensitivity for studying the early effect of nicotine on the cells. Thus, we used an optically ellipsometric method to get the fast and sensitive nicotine effect on the colon cell. Two-dimensional plasmonic platforms by gold deposition onto the polydimethylsiloxane polymer (PDMS) patterned substrate were used as the guest medium of the cell and the sample was excited by all of the visible region wavelengths at different exposure time and maintenance time. Results: Our results showed that the phase difference between each polarization increased by augmenting the exposure time of smoke over the cell at a fixed maintenance time and there was a general red-shift by increasing the maintenance time at a fixed exposure time. Conclusion: Using different exposure time to cigarette smoke, we optically showed that the cigarette containing the addicting chemical of nicotine had a direct effect on the cultured colon cells on our 2D biocompatible plasmonic chip. It demonstrated considerable changes in the amplitude and phase of the interacted light by injecting nicotine into the system with the aid of the label-free and non-invasive plasmonic technique.

Effect of a Low-Level Laser on Liposomal Doxorubicin Efficacy in a Melanoma Cell Line

Introduction: The cytotoxicity of chemotherapy drugs is a significant challenge in the way of surmounting cancer. Liposomal drug delivery has proven to be efficacious in increasing the function of the drugs. Its potential to accumulate drugs in the target site and enhance the efficiency of anti-cancer agents with lower doses hinders their cytotoxicity on normal healthy cells. Since the release of drugs from liposomes is not generally on a controlled basis, several studies have suggested that external stimuli including lasers could be used to induce controlled release and boost the efficiency of liposomal drug delivery systems (LDDSs). Methods: The A375 cancer cell line was used and exposed to the liposomes containing doxorubicin in the presence of a low-level laser beam to investigate its effect on the liposomal stimuli-responsiveness release and its toxicity on cancer cells. So as to achieve that goal, Annexin V/PI was employed to analyze the number of cells that underwent apoptosis and necrosis. Results: Here, we report the effect of laser irradiation on LDDSs. According to the results obtained from the annexin V/PI assay, the pattern of viability status has shifted, so that the number of pre-apoptotic cells treated with liposomal doxorubicin and a laser beam was more than that of cells treated with only liposomal doxorubicin. Conclusion: The use of stimuli-responsive LDDSs, in this case, laser-responsive, has led to favorable circumstances in the treatment of cancer, offering enhanced cancer cell cytotoxicity.

Quantitative Autofluorescence Imaging of A375 Human Melanoma Cell Samples: A Pilot Study

Introduction: Skin cancer is one of the most common types of malignancy worldwide. Human skin naturally contains several endogenous fluorophores, as potential sources can emit inherent fluorescence, called intrinsic autofluorescence (AF). The melanin endogenous fluorophore in the basal cell layer of the epidermis seems to have a strong autofluorescence signal among other ones in the skin. This pilot study aimed to investigate the feasibility of the detection of autofluorescence signals in the A375 human melanoma cell line in the cell culture stage using the FluoVision optical imaging system. Methods: The human skin melanoma cell line (A375) donated as a gift from Switzerland (University Hospital Basel) was cultured. For the imaging of the A375 human melanoma cell sample in this pilot study, the FluoVision optical imaging device (Tajhiz Afarinan Noori Parseh Co) was applied. The proposed clustering image processing code was developed based on the K-mean segmentation method, using MATLAB software (version 16). Results: The quantification of color pixels in the color bar along with the intensity score of the autofluorescence signal ranged between 0 and 70 was written in the image processing code execution and a threshold higher than 40%, proportional to the ratio of autofluorescent cells. The percentage of the signal of A375 autofluorescent melanoma cells in the 3 studied cell samples was calculated as 3.11%±0.6. Conclusion: This imaging method has the advantage of no need for fluorophore labels over the existing fluorescence imaging methods, and it can be regarded as one of the important choices of label-free imaging for this A375 melanoma cell line containing the intrinsic endogenous fluorophore in cell studies.

Effect of Methadone and Tramadol Opioids on Stem Cells Based on Integrated Plasmonic-Ellipsometry Technique

Introduction: Plasmonic biosensors provide high sensitivity in detecting the low amount of biomarkers and pharmaceutical drugs. We studied the mesenchyme cell activity under the treatment of common sedative drugs of methadone and tramadol using the integrated plasmonic-ellipsometry technique. Methods: Mesenchymal stem cells were cultured on patterned plasmonic chips under the treatment of methadone and tramadol drugs. Three cultured chips were kept non-treated as the control ones. The plasmonic-ellipsometry technique was applied to study the signaling characteristic of the cells affected by these two drugs. In this technique, optical information regarding the amplitude ratio and phase change between p- and s-polarized light was recorded. Results: This drug treatment could affect the spectral plasmonic resonance and subsequently the phase shift (Δ) and the amplitude ratio (Ψ) values under p- and s-polarized impinging light. A more significant Δ value for tramadol treatment meant that the phase split was larger between p- and s-polarized light. Tramadol also had more prominent absolute Δ eff and Ψ eff values in comparison with methadone. Conclusion: We showed that tramadol caused more contrast in phase shift (Δ) and amplitude ratio (Ψ) between p- and s-polarized impinging light for cultured stem cells in comparison with methadone. It means that tramadol differentiated more the optical responses for p- and s-polarized lights compared to methadone. Our proposed technique possesses the potential of quantitative and qualitative analysis of drugs on humans even on a cell scale.

Plasmophore Enhancement in Fibroblast Green Fluorescent Protein-Positive Cells Excited by Smoke

Considering the large consumption of nicotine and its sedative/stimulant effect on different organs of the body, the detection of low concentration of this material and its subsequent effect on live animals plays a significant role. Optical detection techniques such as plasmonics are the pioneers in highly sensitive detection techniques. However, for investigating the nicotine/smoke effect on live cells, not only the interaction between cell nicotine should be optimized but also the plasmonic interface should show a high sensitivity to the reception of nicotine by the cell receptors. In this study, the sensitivity of the plasmonic detection system was greatly increased using the coupling of plasmon and fluorophore. This coupling could enhance the main plasmonic signal several orders of magnitude besides improving Δ and Ψ ellipsometry parameters. Benefiting from the green fluorescence proteins, the phase shift and the amplitude ratio between the reflections under s- and p-polarized light enhance considerably which verifies the coupling of the dipole of the fluorescence emitter and the plasmons of the metal nanostructure. For 1 s increase of the maintenance time, we encountered a considerable increase in the Δ values that were 0.15° for T _e = 1 s and 0.24° for T _e = 3 s. Benefiting from extracted ellipsometry parameters, this study could open new avenues toward studying the effect of various types of drugs and stimulants on biological samples using a novel plasmophore platform.

Monitoring the Response of Skin Melanoma Cell Line (A375) to Treatment with Vemurafenib: A Pilot In Vitro Optical Spectroscopic Study

Objective: The aim of this study was to investigate the feasibility of optical spectroscopy as a nondestructive approach in monitoring the skin melanoma cancer cell response to treatment. Background: Owing to the growing trend of personalized medicine, monitoring the treatment response individually is particularly crucial for optimizing cancer therapy efficiency. In the past decade, optical sensing, using diffuse reflectance spectroscopy, has been used to improve the identification of cancerous lesions in various organs. Until now, surveys have mainly focused on the nondestructive application of optical sensing used to diagnose and discriminate normal and abnormal biomedical lesions or samples. Meanwhile, the response to the treatment might be monitored using these nondestructive technologies, thereby enabling further therapeutic modification. Methods: The human skin melanoma cell line (A375) donated from Switzerland (University Hospital Basel) was cultured. Vemurafenib (Zelboraf; Genentech/Roche, South San Francisco, CA) was used for cell treatments. The visible-near-infrared reflectance spectroscopy was conducted at different time intervals (before treatment, and at 1, 2, 7, and 14 days post-treatment for three drug doses 5, 25, and 75 μM) on cell plates using the portable CCD-based fiber optical spectrometer (USB2000; Ocean Optics). After data collection, the refractive index analysis for the fore-mentioned doses and days in one selected wavelength of 620 nm was examined using the previously developed computer program. Then, biological assays were selected as gold standard of cell death, apoptosis, and drug resistance gene expression. Results: There was a considerable decrease in the refractive index of cell samples in which biological assay confirmed cell death. Based on the flow cytometry data, a drug dose of 25 μM on day 7 seemed to induce necrosis. These findings show that spectroscopic findings strongly agree with concurrent biological studies and might lead to their use as an alternative method for monitoring treatment response to achieve more optimized cancer treatment. Conclusions: The findings show that reflectance spectroscopy, as a nondestructive real-time label-free way, is capable of providing quantitative information for treatment response determination that corresponds with biological assays.