Machine learning-assisted SERS approach enables the biochemical discrimination in Bcl-2 and Mcl-1 expressing yeast cells treated with ketoconazole and fluconazole antifungals.

Antifungal medications are important due to their potential application in cancer treatment either on their own or with traditional treatments. The mechanisms that prevent the effects of these medications and restrict their usage in cancer treatment are not completely understood. The evaluation and discrimination of the possible protective effects of the anti-apoptotic members of the Bcl-2 family of proteins, critical regulators of mitochondrial apoptosis, against antifungal drug-induced cell death has still scientific uncertainties that must be considered. Novel, simple, and reliable strategies are highly demanded to identify the biochemical signature of this phenomenon. However, the complex nature of cells poses challenges for the analysis of cellular biochemical changes or classification. In this study, for the first time, we investigated the probable protective activities of Bcl-2 and Mcl-1 proteins against cell damage induced by ketoconazole (KET) and fluconazole (FLU) antifungal drugs in a yeast model through surface-enhanced Raman spectroscopy (SERS) approach. The proposed SERS platform created robust Raman spectra with a high signal-to-noise ratio. The analysis of SERS spectral data via advanced unsupervised and supervised machine learning methods enabled unquestionable differentiation (100 %) in samples and biomolecular identification. Various SERS bands related to lipids and proteins observed in the analyses suggest that the expression of these anti-apoptotic proteins reduces oxidative biomolecule damage induced by the antifungals. Also, cell viability assay, Annexin V-FITC/PI double staining, and total oxidant and antioxidant status analyses were performed to support Raman measurements. We strongly believe that the proposed approach paves the way for the evaluation of various biochemical structures/changes in various cells.

S6K2 promises an important therapeutic potential for cancer.

S6K2, the newer member of S6 Kinase family, is a crucial modulator of Akt/mTOR signaling pathway and is a member of AGC kinase family that regulates cellular growth and survival. S6K1 and S6K2 share high sequence similarity; therefore, S6K2 had been underestimated. However, recent studies displayed distinct functions of S6K2. Activated by both Akt/mTOR and Ras/Raf/Mek/Erk signaling pathways, S6K2 regulates cancer cell survival via different routes. Complexation with antiapoptotic proteins BRAF and PKCε avoids non-small-cell lung cancer cells  from apoptosis upon FGF-2 stimulation. Indirect upregulation of the translation of antiapoptotic proteins Bcl-XL and XIAP in HEK293T cells and interference with TNF-induced apoptosis in MCF-7 cells are other routes of cancer cell survival. The aforementioned studies on S6K2 necessitate the development of therapies targeting only on S6K2. Studies targeting S6K2 may help to build important roads for cancer therapy.

Where EGF receptors transmit their signals.

Excessive signaling by receptor tyrosine kinases (RTKs) can cause cancer. What molecular mechanisms normally control RTK signaling? Are they defective in tumors? If so, should therapeutics be developed to restore particular regulatory pathways to cancer cells? These questions have been approached through mechanistic studies of a prototypical RTK, the epidermal growth factor receptor (EGFR). EGFR signaling is mediated and regulated by both signaling and trafficking effectors. The amplitude of receptor-proximal signals changes as EGFRs move along the degradative trafficking pathway from the cell surface, to endosomes, and into lysosomes. To optimize therapeutic suppression of receptor oncogenicity, it may be crucial to target EGFRs that are signaling from a specific site in the trafficking pathway. Research suggests that EGFRs at the plasma membrane produce the bulk of the global transcriptional response to EGF. EGFRs localized between the internalization and early endosome fusion stages of the pathway enrich the expression of transcripts associated with cancer. EGFRs at later trafficking checkpoints controlled by the endosomal sorting complex required for transport (ESCRT) complexes II and III do not contribute substantially to the EGFR-mediated transcriptional response. These results suggest that therapeutics targeting the receptors at the earliest stages of degradative trafficking might be most effective.

Use of miRNA expression profiling to identify novel biomarkers.

Micro (mi)RNAs are small, noncoding RNAs that regulate gene expression through binding to the 3´-untranslated region of mRNAs by complementary base pairing and mainly act through cleavage or translational inhibition of mRNAs. Recent studies have shown the roles of miRNAs in development and cancer, revealing the physiological and pathological importance of these tiny molecules. Therefore, as with mRNAs, researchers have focused on the global analyses of miRNAs to seek their potential use as biomarkers for physiological and pathological states of a cell. Methods developed for miRNA profiling are briefly discussed in this review. Recent evidences supporting the use of miRNAs as biomarkers in both differentiation and cancer are presented. The profiling studies may highlight the clinical relevance of miRNAs and will enable the researchers to uncover the enormous potential of these tiny molecules. In the near future, selected miRNA genes based on expression abnormalities will be tested as candidates for miRNA-based cancer gene therapy.