The Role of Natural Flavonoids as Telomerase Inhibitors in Suppressing Cancer Growth.

Cancer is a complex and multifaceted group of diseases characterized by the uncontrolled growth and spread of abnormal cells. While cancer can be challenging and life-altering, advances in research and development have led to the identification of new promising anti-cancer targets. Telomerase is one such target that is overexpressed in almost all cancer cells and plays a critical role in maintaining telomere length, which is essential for cell proliferation and survival. Inhibiting telomerase activity can lead to telomere shortening and eventual cell death, thus presenting itself as a potential target for cancer therapy. Naturally occurring flavonoids are a class of compounds that have already been shown to possess different biological properties, including the anti-cancer property. They are present in various everyday food sources and richly present in fruits, nuts, soybeans, vegetables, tea, wine, and berries, to name a few. Thus, these flavonoids could inhibit or deactivate telomerase expression in cancer cells by different mechanisms, which include inhibiting the expression of hTERT, mRNA, protein, and nuclear translocation, inhibiting the binding of transcription factors to hTERT promoters, and even telomere shortening. Numerous cell line studies and in vivo experiments have supported this hypothesis, and this development could serve as a vital and innovative therapeutic option for cancer. In this light, we aim to elucidate the role of telomerase as a potential anti-cancer target. Subsequently, we have illustrated that how commonly found natural flavonoids demonstrate their anti-cancer activity via telomerase inactivation in different cancer types, thus proving the potential of these naturally occurring flavonoids as useful therapeutic agents.

Apoptotic Mechanisms of Quercetin in Liver Cancer: Recent Trends and Advancements.

Due to rising incidence rates of liver cancer and worries about the toxicity of current chemotherapeutic medicines, the hunt for further alternative methods to treat this malignancy has escalated. Compared to chemotherapy, quercetin, a flavonoid, is relatively less harmful to normal cells and is regarded as an excellent free-radical scavenger. Apoptotic cell death of cancer cells caused by quercetin has been demonstrated by many prior studies. It is present in many fruits, vegetables, and herbs. Quercetin targets apoptosis, by upregulating Bax, caspase-3, and p21 while downregulating Akt, PLK-1, cyclin-B1, cyclin-A, CDC-2, CDK-2, and Bcl-2. Additionally, it has been reported to increase STAT3 protein degradation in liver cancer cells while decreasing STAT3 activation. Quercetin has a potential future in chemoprevention, based on substantial research on its anticancer effects. The current review discusses quercetin's mechanisms of action, nanodelivery strategies, and other potential cellular effects in liver cancer.

Immunotherapeutics in lung cancers: from mechanistic insight to clinical implications and synergistic perspectives.

BACKGROUND: Lung cancer is one of the highly lethal forms of cancer whose incidence has worldwide rapidly increased over the past few decades. About 80-85% of all lung cancer cases constitute non-small cell lung cancer (NSCLC), with adenocarcinoma, squamous cell carcinoma and large cell carcinoma as the main subtypes. Immune checkpoint inhibitors have led to significant advances in the treatment of a variety of solid tumors, significantly improving cancer patient survival rates. METHODS AND RESULTS: The cytotoxic drugs in combination with anti-PD-(L)1 antibodies is a new method that aims to reduce the activation of immunosuppressive and cancer cell prosurvival responses while also improving direct cancer cell death. The most commonly utilized immune checkpoint inhibitors for patients with non-small cell lung cancer are monoclonal antibodies (Atezolizumab, Cemiplimab, Ipilimumab, Pembrolizumab etc.) against PD-1, PD-L1, and CTLA-4. Among them, Atezolizumab (TECENTRIQ) and Cemiplimab (Libtayo) are engineered monoclonal anti programmed death ligand 1 (PD-L1) antibodies that inhibit binding of PD-L1 to PD-1 and B7.1. As a result, T-cell proliferation and cytokine synthesis are inhibited leading to restoring the immune homeostasis to fight cancer cells. CONCLUSIONS: In this review article, the path leading to the introduction of immunotherapeutic options in lung cancer treatment is described, with analyzing the benefits and shortages of the current immunotherapeutic drugs. In addition, possibilities to co-administer immunotherapeutic agents with standard cancer treatment modalities are also considered.

Molecular mechanisms behind ROS regulation in cancer: A balancing act between augmented tumorigenesis and cell apoptosis.

ROS include hydroxyl radicals (HO.), superoxide (O2..), and hydrogen peroxide (H2O2). ROS are typically produced under physiological conditions and play crucial roles in living organisms. It is known that ROS, which are created spontaneously by cells through aerobic metabolism in mitochondria, can have either a beneficial or detrimental influence on biological systems. Moderate levels of ROS can cause oxidative damage to proteins, DNA and lipids, which can aid in the pathogenesis of many disorders, including cancer. However, excessive concentrations of ROS can initiate programmed cell death in cancer. Presently, a variety of chemotherapeutic drugs and herbal agents are being investigated to induce ROS-mediated cell death in cancer. Therefore, preserving ROS homeostasis is essential for ensuring normal cell development and survival. On account of a significant association of ROS levels at various concentrations with carcinogenesis in a number of malignancies, further studies are needed to determine the underlying molecular mechanisms and develop the possibilities for intervening in these processes.

Role of Hedgehog and Hippo signaling pathways in cancer: A special focus on non-coding RNAs.

Despite advanced clinical and translational oncology research, mortality rates are still increasing worldwide. Recently, a class of non-coding RNAs (ncRNAs), such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), have been well investigated in regulating biological, molecular, and cellular signaling pathways. This review article provided the current research progress on how miRNAs, lncRNAs, and circRNAs regulate Hedgehog (Hh) and Hippo signaling pathways in various cancers. These ncRNAs target both pathways' key downstream molecules and may be used for targeted cancer treatment. Moreover, Hh and Hippo signaling pathways crosstalked with each other through Gli1 of Hh pathways and YAP1/TEAD molecules of Hippo pathways during cancer progression. Additionally, Hh and Hippo signaling pathways regulate resistance against the chemo, radio, and immune therapies for several types of cancer via inducing GLI and YAP/TAZ proteins level. Therefore, to improve the treatment regime, we presented the role of various prominent phytochemicals such as curcumin, resveratrol, genistein, quercetin, paclitaxel, and silibinin in regulating lncRNAs, miRNAs, circRNA through Hedgehog and Hippo signaling pathways' constituents in cancers. We believe that knowledge obtained from this review may help make new drugs for cancer treatment in the future.

Luteolin, a Potent Anticancer Compound: From Chemistry to Cellular Interactions and Synergetic Perspectives.

Increasing rates of cancer incidence and the toxicity concerns of existing chemotherapeutic agents have intensified the research to explore more alternative routes to combat tumor. Luteolin, a flavone found in numerous fruits, vegetables, and herbs, has exhibited a number of biological activities, such as anticancer and anti-inflammatory. Luteolin inhibits tumor growth by targeting cellular processes such as apoptosis, cell-cycle progression, angiogenesis and migration. Mechanistically, luteolin causes cell death by downregulating Akt, PLK-1, cyclin-B1, cyclin-A, CDC-2, CDK-2, Bcl-2, and Bcl-xL, while upregulating BAX, caspase-3, and p21. It has also been reported to inhibit STAT3 signaling by the suppression of STAT3 activation and enhanced STAT3 protein degradation in various cancer cells. Therefore, extensive studies on the anticancer properties of luteolin reveal its promising role in chemoprevention. The present review describes all the possible cellular interactions of luteolin in cancer, along with its synergistic mode of action and nanodelivery insight.

Recent Advances in Immunotherapy for the Treatment of Malignant Melanoma.

Malignant melanoma is one of the most worrisome malignancies due to its fast dissemination and early formation of metastases in multiple sites throughout the body. Despite the intensive efforts made in the last decades, the use of standard therapeutic strategies, including chemotherapy and radiotherapy, has not led to a substantial improvement in clinical outcomes, mainly because of the intrinsic resistance of melanomas to these treatment modalities. Therefore, in recent years, numerous studies have focused on the possibility of boosting the clinical responses of melanoma patients by using novel immunotherapeutic agents. In this review article, a comprehensive survey is presented about the approved immunotherapeutic drugs and their action mechanisms, besides describing the agents that are currently still in clinical trials. Moreover, the combination of immunotherapeutic drugs with conventional approaches, i.e., radiotherapy, chemotherapy, and targeted therapy, is another focal point of this review, providing valuable input for further elaboration of the best treatment regimens to prolong survival and improve the quality of life of melanoma patients.

Anti-Inflammatory and Anticancer Properties of Birch Bark-Derived Betulin: Recent Developments.

Birch tree bark-derived betulin has attracted scientific interest already for several centuries, being one of the first natural products identified from plants. However, the cellular events regulated by betulin and precise molecular mechanisms under these processes have been begun to be understood only recently. Today, we know that betulin can exert important anticancer activities through modulation of diverse cellular pathways. In this review article, betulin-regulated molecular signaling is unraveled and presented with a special focus on its participation in anti-inflammatory processes, especially by modulating nuclear factor-κB (NF-κB), prostaglandin/COX, and nuclear factor erythroid2-related factor 2 (Nrf2)-mediated cascades. By regulating these diverse pathways, betulin can not only affect the development and progression of different cancers, but also enhance the antitumor action of traditional therapeutic modalities. It is expected that by overcoming the low bioavailability of betulin by encapsulating it into nanocarriers, this promising natural compound may provide novel possibilities for targeting inflammation-related cancers.

Role of alpha-melanocyte stimulating hormone (α-MSH) in modulating the molecular mechanism adopted by melanocytes of Bos indicus under UVR stress.

Ultraviolet radiations (UVR) are responsible for a wide variety of acute and chronic effects on the animal skin. However, the effect of UVR-induced oxidative stress and protection through paracrine factors on animal skin has received little attention. We previously demonstrated how heat stress-induced adaptation in Bos indicus melanocytes was dependent on the level of melanin and reduction of apoptosis. Therefore, in the present investigation, the survival mechanisms adopted by melanocytes under UV stress and the role of α-MSH in cell survival under in vitro conditions were studied. After the treatment of melanocyte cells with UVR (using Osram ultravitalux 300 W lamp), analysis of Gene expression using Real-Time PCR was done to study the adopted molecular pathways under stressful conditions. In addition, α-MSH was used to assess its modulating role in cell survival under stress. This study revealed the increase in the expression of genes related to melanogenesis, cell cycle, heat shock proteins, and apoptosis of the cells after UVR stress and demonstrated the role of paracrine factor (α-MSH) in elevating the protection response to stressful conditions like UVR stress by increasing the melanogenesis and decreasing the mitochondrial-mediated apoptosis. Based on the results of the present study, it can be stated that α-MSH can play a pivotal role in the protection of animal skin cells under stressful conditions in climate-changing scenario.

Novel extraction of high quality genomic DNA from frozen bovine blood samples by using detergent method.

DNA is the prerequisite for life's inception that transfers hereditary information, past several years; various types of commercial kits are made available which vary depending on the type of the biological sample being used. The present study is focused on developing an improvised methodology for the isolation of genomic DNA from stored bovine blood samples. DNA was isolated by using the conventional Phenol: Chloroform: Isoamyl alcohol (PCI) method and Detergent method. The aim of the study was to make a comparative analysis and evaluation of these two methods to identify the one that gives a superior quality and quantity of genomic DNA. Total (n=48) each duplicate blood samples from three different buffalo(Bubalus bubalis) breeds Banni, Surti, Murrah, three zebu cattle (Bos indicus) breeds Kankerj, Gir, Sahiwal were collected from the jugular vein. The quantity, purity of the genomic DNA was assessed based on the total DNA yield, purity ratios, spectral profile, agarose gel electrophoresis analysis and polymerase chain reaction amplification of MC1R gene product without any inhibitors. The results of our study suggest that detergent method is also suitable for extraction of genomic DNA from the bovine blood and results were significant (*P>0.05). The total mean yield was found to be 329.05±11 µg/5ml for all six breeds while the PCI method was employed. The total mean yield of the gDNA for all six breeds was 406.6±43 µg/5ml of blood when the detergent method was used. One way ANOVA test showed that the total DNA yield varied depending on the isolation method used. The DNA yield obtained from the DG method was (***P< 0.001) significant as compared to the PCI method (**P<0.01).

Validation of putative reference genes for gene expression studies in heat stressed and α-MSH treated melanocyte cells of Bos indicus using real-time quantitative PCR.

Normalization of cellular mRNA data using internal reference gene (IRG) is an essential step in expression analysis studies. MIQE guidelines ensure that the choice and appropriateness of IRG should be validated for particular tissues or cell types and specific experimental designs. The objective of the present study was to assess 15 IRGs from different functional classes that could serve as best IRGs for Bos indicus (Tharparkar cattle) melanocyte cells under heat stress and hormonal treatment. We implemented the use of geNorm, NormFinder and BestKeeper algorithm to measure the stability of the gene transcript. A total of 15 IRGs (ACTB, BZM, EEF1, GAPDH, GTP, HMBS, HPRT, RPL22, RPL4, RPS15, RPS18, RPS23, RPS9, UBC and UXT) from different functional classes were evaluated. Pair wise comparisons using geNorm revealed that HPRT and RPS23 were the most stable combination of IRGs with M-value of 0.29 followed by UXT (0.30) and RPL4 (0.31). The NormFinder analysis also identified the same set of stably expressed genes (UXT, RPL4, RPS23 and HPRT); however, the rank order was little different. The UXT gene showed lowest crossing point SD and CV values of 0.30 and 1.17, respectively indicating its maximum expression stability through BestKeeper analysis. The present study indicated that, ACTB and HMB were not reliable IRGs for melanocytes cells on account of their lower expression stability. Current study further revealed that UXT, HPRT and RPS23 are the best IRGs for normalization of qPCR data in Bos indicus melanocyte cells under heat stress and hormonal treatment.