Mechanistic role of pyroptosis in tumor microenvironment and tumor immunotherapy.

In recent decades, extraordinary attention has been devoted to cell death pathways principally because of multifaceted regulatory roles in normal developmental and pathophysiological processes. The removal of functionally defective, infected or potentially malignant cells is regulated by programmed cell death (PCD) cascades.  Pyroptotic cell death is a highly complicated pro-inflammatory form of cell death. Pyroptosis is characterized by the formation of pores in the plasma membrane by oligomerization of the N-terminal fragment of gasdermins (gasdermin-NT) following the cleavage of gasdermin. Pyroptosis plays a pivotal role in the innate immune responses and mechanistically steered by inflammasome-mediated and inflammasome-independent cascades. In this review, we have comprehensively analyzed how different signaling pathways regulated pyroptosis in cancer inhibition and metastatic spread of cancer cells to the secondary sites. Comprehensive understanding of the interconnection between signaling pathways and pyroptosis will enable us to reap maximum benefits from the exciting mechanistic insights gained from pioneering studies related to pyroptosis.

Regulatory role of circular RNAs in oral squamous cell carcinoma.

OSCC is a genomically complicated disease and advancements in the modern era of molecular oncology have enabled researchers to portray near-to-complete resolution of signaling landscape. Over the last two decades, overwhelming proof-of-concept has established mechanistic regulatory role of non-coding RNAs in carcinogenesis, including OSCC. Circular RNAs demonstrate a burgeoning facet of oncology research and molecular biologists are only beginning to appreciate and recognize the significance of circRNAs in the pathogenesis of OSCC. Regulatory roles of non-coding RNAs in the re-shaping of signaling pathways offer plausible strategies for prevention/inhibition of OSCC. Circular RNAs have mechanistic roles in OSCC and "sponge effects" mediated by a wider variety of circRNAs need to be rationally targeted for effective cancer prevention. Phenomenal and cutting-edge research works in different types of animal models will further refine our knowledge for selection of most promising circRNAs as pharmacologically valuable targets.

Role of DNA Methyltransferases (DNMTs) in metastasis.

The DNA methyltransferase (DNMT) family constitutes a conserved set of DNA-modifying enzymes which have essential functions in the modulation of epigenetics. The fundamental role of epigenetic changes in carcinogenesis and metastasis is increasingly being appreciated. DNMTs (DNMT1, DNMT3A and DNMT3B) have been shown to drive metastasis. Epigenetic machinery is installed at the target sites for the regulation of a wide variety of genes. Moreover, microRNAs, long non-coding RNAs and circular RNAs also shape the epigenetic landscape during metastasis. In this review, we have provided a snapshot of the quintessential role of DNMTs in metastasis. We also summarize how lncRNAs and circRNAs play roles in the epigenetic regulation of a myriad of genes.

Frontiers of Ferroptosis in Cancer Treatment.

Recent phenomenal advancements in genomic and proteomic technologies and rapid breakthroughs in the interpretation of large gene expression datasets have enabled scientists to comprehensively characterize the gene signatures involved in ferroptosis. Ferroptosis is an iron-dependent form of non-apoptotic cell death that has gained the worthwhile attention of both basic and clinical researchers. Ferroptosis has dichotomous, context-dependent functions both as a tumor suppressor and promoter of carcinogenesis. Essentially, pharmacological modulation of ferroptosis by its induction as well as its inhibition holds enormous potential to overcome drug resistance and to improve the therapeutic potential of chemotherapeutic drugs in a wide variety of cancers.

Luteolin mediated targeting of protein network and microRNAs in different cancers: Focus on JAK-STAT, NOTCH, mTOR and TRAIL-mediated signaling pathways.

There has always been a keen interest of basic and clinical researchers to search for cancer therapeutics having minimum off-target effects and maximum anticancer activities. In accordance with this approach, there has been an explosion in the field of natural products research in the past few decades because of extra-ordinary list of natural extracts and their biologically and pharmacologically active constituents having significant medicinal properties. Apparently, luteolin-mediated anticancer effects have been investigated in different cancers but there is superfluousness of superficial data. Generalized scientific evidence encompassing apoptosis, DNA damage and anti-inflammatory effects has been reported extensively. However, how luteolin modulates deregulated oncogenic pathways in different cancers has not been comprehensively uncovered. In this review we have attempted to focus on cutting-edge research which has unveiled remarkable abilities of luteolin to modulate deregulated oncogenic pathways in different cancers. We have partitioned the review into various sections to separately discuss advancements in therapeutic targeting of oncogenic protein networks. We have provided detailed mechanistic insights related to JAK-STAT signaling and summarized how luteolin inhibited STAT proteins to inhibit STAT-driven gene network. We have also individually analyzed Wnt/ß-catenin and NOTCH pathway and how luteolin effectively targeted these pathways. Mapping of the signaling landscape has revealed that NOTCH pathway can be targeted therapeutically. NOTCH pathway was noted to be targeted by luteolin. We have also conceptually analyzed how luteolin restored TRAIL-induced apoptosis in resistant cancers. Luteolin induced an increase in pro-apoptotic proteins and efficiently inhibited anti-apoptotic proteins to induce apoptosis. Luteolin mediated regulation of non-coding RNAs is an exciting and emerging facet. Excitingly, there is sequential and systematic accumulation of clues which have started to shed light on intricate regulation of microRNAs by luteolin in different cancers. Collectively, sophisticated information will enable us to develop a refined understanding of the multi-layered regulation of signaling pathways and non-coding RNAs by luteolin in different cancers.

Regulation of NLRP3 by non-coding RNAs in different cancers: interplay between non-coding RNAs and NLRP3 in carcinogenesis and metastasis.

NLRP3 (NOD-, LRR- and pyrin domain-containing protein 3) inflammasomes are multitasking intracellular sensors having characteristically unique ability to detect myriad of microbial motifs and endogenous danger signals which promote structural assembly of NLRP3 inflammasome thus enabling it to perform instrumental roles. Detailed mechanistic insights revealed that molecularly assembled NLRP3 inflammasomes stimulated caspase-1-driven release of the pro-inflammatory cytokines. NLRP3 has been shown to play fundamental role in the regulation of cancer progression and metastasis. Recently emerging cutting-edge research-works have started to shed light on the involvement of non-coding RNAs in the regulation of NLRP3 in different cancers. MicroRNAs, lncRNAs and circular RNAs have been shown to modulate NLRP3 in different diseases. However, we still have incomplete information about regulation of NLRP3 by circular RNAs in various cancers. In this review, we will comprehensively analyze how different microRNAs and long non-coding RNAs modulate NLRP3 in human cancers. Emerging evidence has started to scratch the surface of the participation of miRNAs and lncRNAs in the regulation of NLRP3. Xenografted mice-based studies have also enabled us to develop a better comprehension of interplay between miRNAs, lncRNAs and NLRP3. Hopefully, detailed analysis of contextual regulation of NLRP3 by oncogenic and tumor suppressor miRNAs, lncRNAs and circRNAs will be helpful in getting a step closer to the personalized medicine.

Calcium based siRNA coating: a novel approach for knockdown of HER2 gene in MCF-7 cells using gold nanoparticles.

Surface functionalization of nanoparticles (NPs) for therapeutic siRNA delivery into cancer cells has gained interest. The present study was designed for surface functionalization of gold nanoparticles (AuNPs) for efficient siRNA delivery and knockdown in cancer cells. In order to achieve this objective, AuNPs were coated with HER2-siRNA in the presence of 11-mercaptoundecanoic acid (11-MUA), calcium chloride (CaCl2) and polyethyleneimine (PEI) in alternate charge bearing successive layers. MCF-7 cells were cultured and transfected with fabricated assembly of AuNPs. Cytotoxicity analysis revealed that the half inhibitory concentration (IC50) for the formulation was 45.35 nM  . Total RNA was isolated from transfected cells, reverse transcribed into complementary DNA (cDNA) and real-time polymerase chain reaction (RT-PCR) was performed. The RT-PCR based delta-delta Ct analysis in treated cells revealed a significant 18.94 times decrease (p<0.001) in the expression of HER2 gene standardized with ACTB housekeeping gene as compared to untreated cells, which makes this formulation a potent approach for siRNA delivery and  gene knockout.

Piceatannol mediated regulation of deregulated signaling pathways in different cancers: Tumbling of the ninepins of molecular oncology.

With the recent technological advancements, a new golden era of natural products drug discovery has dawned. Increasingly it is being realized that structural modularity of many pharmacologically active products derived natural sources allows a building-block approach which can be exploited for analysis of regulation of deregulated oncogenic protein networks in different cancers. Piceatannol has been shown to effectively modulate JAK/STAT, Wnt/ß-catenin, mTOR pathway in different cancers. In addition, certain hints have emerged which shed light on the regulation of microRNAs by piceatannol in some cancers. Regulation of deregulated oncogenic pathways by Piceatannol is gradually capturing attention and might be helpful in the multi-targeting of deregulated oncogenic networks in cancers.

TRAIL mediated signaling in different cancers: cancer in the "Crosshairs".

Cancer is a therapeutically challenging disease because of its heterogeneous and multifaceted nature. Decades of research have sequentially and systematically enabled us to develop a sharper and better understanding of the heterogeneous nature of cancer. Genetic, genomic and proteomic studies have unraveled wide-ranging signaling cascades which play cornerstone role in disease onset and progression. More importantly, activation of pro-survival signaling and loss of apoptosis also play critical role in cancer progression. TRAIL-mediated signaling pathway has emerged as one of the most comprehensively analyzed cascade because of its exceptional ability to target cancer cells while leaving normal cells intact. TRAIL discovery and landmark achievements related to TRAIL/TRAIL-receptor signaling pathway attracted the attention of researchers. Therefore, scientists started to add missing pieces to an incomplete jig-saw puzzle and allowed contemporary researchers to conceptualize a better molecular snapshot of TRAIL-induced signaling in various cancers. Circumstantial evidence illuminated a functionally unique "push and pull" between anti-apoptotic and pro-apoptotic proteins in different cancers. Overexpression of anti-apoptotic proteins and inactivation of pro-apoptotic proteins shifted the balance towards loss of apoptosis. There has been a breakneck increase in the number of clinical trials related to TRAIL-based therapeutics which validate the true pharmacological potential of TRAIL-based therapeutics as effective anticancer agents. However, apart from advancements in our clinical understanding about the efficacy of TRAIL-based therapeutics, researchers have also faced setbacks in the field of translational medicine. Therefore, in this review, we have attempted to set spotlight on the most recent and landmark discoveries which have leveraged our understanding related to TRAIL-mediated signaling altogether to a new level.

TRAIL mediated signaling as a double-edged sword in pancreatic cancer: Analysis of brighter and darker sides of the pathway.

Genetic, genomic and proteomic studies have refined our concepts related to underlying mechanisms of pancreatic cancer. Increasingly sophisticated knowledge has started to shed light on the fact that pancreatic cancer harbored multiple epigenetic and genetic alterations and revealed complicated and dense tumor microenvironments. Our rapidly evolving knowledge about pancreatic cancer has helped us in identification of myriad of underlying mechanisms which play instrumental role in disease onset, drug resistance and epithelial to mesenchymal transition (EMT). Additionally, loss of apoptosis is the cornerstone of cancer biology and researchers have devoted considerable attention to the versatile regulators involved in loss and restoration of apoptosis. Discovery of TNF/TNFR, FasL/Fas and TRAIL/TRAIL-R opened new horizons for detailed analysis of intracellular mechanisms regulated by these pro-apoptotic molecules. Decades of cutting-edge research helped in translation of TRAIL-based therapeutics into clinically effective therapeutics. In this review, we will focus specifically on groundbreaking achievements which have leveraged our concepts related to TRAIL-mediated signaling to yet another level. We will also discuss how basic and clinical scientists are making efforts to overcome the stumbling blocks associated with efficacy of TRAIL-based therapeutics against TRAIL-resistant pancreatic cancers. We partition this multi-component review into overview of the conceptual breakthroughs in regulation of TRAIL-mediated signaling in pancreatic cancers, push and pull between pro- and anti-apoptotic proteins to regulate TRAIL-mediated apoptosis and how researchers have identified different natural and synthetic molecules to restore apoptosis in TRAIL-resistant pancreatic cancer. We have also summarized how long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) regulated TRAIL-mediated apoptosis in pancreatic cancer. More importantly we will also set spotlight on the darker side of TRAIL/TRAIL-R pathway in pancreatic cancer. Circumstantial evidence highlighted cancer promoting role of TRAIL/TRAIL-R in pancreatic cancer. These diametrically opposed context-dependent roles of TRAIL-pathway are intriguing and need comprehensive research to address outstanding questions.

The protective role of melatonin against the effects of different doses of caffeine on the fetus.

Skeletal system and some organs development changes in rat fetuses with 30 and 60 mg/kg caffeine and melatonin's (10 mg/kg) protective role against rat fetuses were investigated. Groups (n = 4) were formed as Control, LDC, HDC, LDC+melatonin, HDC+melatonin and melatonin. Fetuses were taken by cesarean section and stained using dual skeletal staining method and FESEM. TRAP and AP immune-reactivity concentrations were calculated.  Oxidative stress and inflammatory markers were also measured by liver, bone and placenta samples.  TNF-α, IL-1ß, IL-6, VEGF-A, SOST and Fetuin-A levels were measured in tissue by using ELISA. TBARS, SOD, GSH, GSSG, TOS, TAS, measured by spectrophotometric assay method.  The mRNA levels of Agtr2 gene expressed in placental tissues of control rats and in placental tissues of rats exposed to HDC, LDC, MEL, HDC+MEL, LDC+MEL were analyzed by Real-time PCR. The gene expressions of Agtr2 were significantly upregulated in the placentas exposed to HDC, MEL, HDC+MEL and LDC+MEL (P<0,001). No significant difference in samples of the LDC group (P>0,05). According to these data, caffeine used during pregnancy delayed ossification; melatonin, a powerful antioxidant, was found to eliminate this effect. Besides, changes in angiotensin receptor expression observed in response to a caffeine and melatonin exposure result from high dose and join effect.

Bioactivity evaluation and HPLC UV-VIS based quantification of antioxidant secondary metabolites from extract and fractions of Bistorta amplexicaulis rhizome.

Bistorta amplexicaulis is a popular medicinal plant and reported as rich source of antioxidant compounds. The present study was designed for antioxidant and anticancer potential of polarity based fractions of B. amplexicaulis and its correlation to the secondary metabolites quantified by HPLC-UV/VIS.Crude extract was prepared by maceration method and polarity based fractions were prepared by solvent-solvent extraction. Antioxidant and anticancer potential was investigated by using various physiological and non-physiological assays while secondary metabolites rutin, naringin and quercetin present in extract and fractions were quantified by using HPLC- UV/VIS. All extracts showed Antioxidant potential but highest activity was obtained with ethyl acetate fraction (DPPH IC50 5.76±0.03 µg/ml, ABTS IC50 0.74±0.1 µg/ml, Total Antioxidant Assay 72.55±0.098 Ascorbic acid equivalents, Super oxide radical scavenging assay IC506.86±0.1909 µg/ml, Hydroxyl radical scavenging assay IC50 0.96±0.1690 µg/ml). The cytotoxicity of fractions against HepG2 cell lines showed lowest ell viability in n-hexane fraction (11%). The results revealed that ethyl acetate fraction of B. amplexicaulis can be a potential source of novel antioxidant compounds while n hexane fraction could provide anticancer compounds. A new method of simultaneous quantification of three flavonoids by using UV/VIS detector is reported in this study.

Regulation of Kisspeptin mediated signaling by non-coding RNAs in different cancers: the beginning of a new era.

Kisspeptin-driven intracellular signaling has captured enormous attention because of its central role in cancer onset and progression. Wealth of information has helped us to develop a better understanding of the critical roles of Kisspeptin-mediated signaling in different cancers. However, astonishingly, we have not yet drilled down deep into the mysterious aspects associated with non-coding RNA mediated regulation of Kisspeptin-driven signaling. Therefore, in this mini-review, we will comprehensively analyze available evidence related to miRNAs and long non-coding RNAs (LncRNAs) and their ability to modulate Kisspeptin-mediated signaling. There are visible knowledge gaps about interplay between non-coding RNAs and Kisspeptin-mediated signaling. It will be appropriate to say that we have just started to scratch the surface of an entirely new regulatory layer of Kisspeptin-mediated transduction cascade. Mechanistically, it has been revealed that inhibition of Kisspeptin mediated signaling activated and stimulated the entry of NFκB into the nucleus to stimulate expression of proteins which can sequentially inactivate tumor suppressor miRNAs. miRNAs have also an instrumental role in regulation of proteins which post-translationally modify and inhibit KISS1 expression. It is becoming progressively more understandable that LncRNAs act as miRNA sponges and protect oncogenic mRNAs. However, these facets are also incompletely investigated. Identification of LncRNAs which interfere with Kisspeptin-mediated pathway either through acting as miRNA sponges or working with methylation-associated machinery will be helpful in sharpening the resolution of the pixels of the regulatory network which shapes Kisspeptin-mediated signaling.

MicroRNA-143 as a new weapon against cancer: overview of the mechanistic insights and long non-coding RNA mediated regulation of miRNA-143 in different cancers.

Central dogma of molecular biology, a term coined by Francis Crick in 1958 was considered to be the cornerstone of molecular biology unless molecular biologists challenged the idea after ground-breaking discovery of non-coding RNAs. Discovery of microRNAs marked a new era and revolutionized our understanding related to puzzling mysteries about intermediate steps between transcription and translation. Technological advancements have spawned a multitude of platforms for profiling of long-noncoding RNAs and miRNAs in different cancers. Detailed investigation of mRNA targets of miRNAs has enabled high-order analyses of interconnected networks and revealed affected pathways in different cancers. miR-143 has emerged as a multi-talented tumor suppressor microRNA having considerable ability to inhibit and prevent cancer via regulation of myriad of oncogenes. In this review, we will summarize most recent evidence related to characteristically unique ability of miR-143 to target different oncogenic mRNAs in different cancers. We will also comprehensively discuss how scientists have identified multiple long non-coding RNAs reportedly involved in promoting the expression of oncogenes by interfering with miR-143 mediated targeting of these oncogenes. Because of excellent ability of miR-143 to effectively target oncogenic mRNAs, researchers have started to focus on use of miR-143 mimics to restore expression of miR-143 in various cancers.

Gene variants of TCF7L2 are histopathologically important in colorectal cancers but do not have direct association with MYC expression.

Rapidly accumulating preclinical and clinical studies have helped us to unveil underlying mechanisms of colorectal cancer development and progression. Deregulated signaling pathways play instrumental role in carcinogenesis, drug resistance and metastasis. Wnt signaling cascade has attracted considerable attention in colorectal cancer as many ground-breaking researches have highlighted central role of Wnt pathway in pathogenesis of colorectal cancer. T-Cell Transcription Factors (TCFs) have been shown to work synchronously with ß-catenin to fuel colorectal cancer development and progression. Chromatin immuno-precipitation coupled with high-throughput sequencing (ChIP-Seq) data sets has deepened our knowledge about critical role of risk-associated SNPs. Increasingly it is being reported that many risk-associated SNPs are located within binding sites for transcription factors and consequently risk status of these SNPs may modify binding pattern of transcriptional factors and thus rewire the transcriptional regulation. DNA was extracted from peripheral blood samples of 117 colorectal cancer patients and 127 healthy subjects. TCF7L2 variants (rs6983267, rs7903146) were examined by the PCR-RFLP method. Tumor and the surrounding tissues were dissected from 37 CRC patients and RNA isolation was performed. The gene expression of c-myc was determined by RT-PCR. T allele carriage of rs6983267 variant was found to be associated with CRC (p=0.042). TT genotype of rs7903146 was associated with late tumor stage (T3+T4) (p=0.037) and presence of mucinous component (p=0.031). TTCT haplotype was found to be statistically higher in CRC compared to the control group (p=0.007). There was no statistically significant difference in c-myc gene expression. TCF7L2 gene variants may play an important role in histopathologic aspects associated with CRC and it is independent of c-myc gene expression.

Focusing on the brighter side of Sevoflurane: Realizing true potential of an anesthetic agent as a regulator of cell signaling pathways and microRNAs in different cancers.

Reconceptualization of different anesthetics as anticancer agents has opened new horizons for a better and sharper analysis of true potential of Sevoflurane as a promising and frontline candidate in the pipeline of anticancer agents. Sevoflurane mediated regulation of cell signaling pathways and non-coding RNAs has leveraged our understanding to another level. There have been remarkable advancements in unraveling mechanistic insights related to the ability of sevoflurane to modulate microRNAs in different cancers. Astonishingly, sevoflurane mediated regulation of miRNAs and long non-coding RNAs have been more comprehensively addressed in ischemia-reperfusion injuries. However, researchers yet have to gather missing pieces of premium research-work to uncover mechanistic regulation of long non-coding RNAs by sevoflurane in various cancers. Sevoflurane modulated control of miRNAs have been reported in glioma, colorectal cancer, breast cancer and hepatocellular carcinoma. In this review we have attempted to summarize most recent cutting edge and high-impact experimental researches which have elucidated myriad of underlying mechanisms modulated by sevoflurane to inhibit cancer development and progression. Despite some of the amazing pharmacological properties of sevoflurane, it has been shown to possess darker side because of its involvement in positive regulation of metastasis.  In accordance with this notion we have also summarized how sevoflurane enhanced migratory potential of different cancer cells in a separate section. Therefore, these aspects have to be tested in better designed experimental models to identify most relevant types of cancers which can be therapeutically targeted by sevoflurane.

Regulation of signaling pathways by Ampelopsin (Dihydromyricetin) in different cancers: exploring the highways and byways less travelled.

Ampelopsin or Dihydromyricetin is gradually emerging as a high-quality natural product because of its ability to modulate wide-ranging signaling pathways. Ampelopsin (Dihydromyricetin) has been reported to effectively modulate growth factor receptor (VEGFR2 and PDGFRß) mediated signaling,  TRAIL/TRAIL-R pathway, JAK/STAT and mTOR-driven signaling in different cancers. Ampelopsin (Dihydromyricetin) has also been shown to exert inhibitory effects on the versatile regulators which trigger EMT (Epithelial-to-Mesenchymal Transition). Findings obtained from in-vitro studies are encouraging and there is a need to comprehensively analyze how Ampelopsin (Dihydromyricetin) inhibits tumor growth in different cancer models. Better knowledge of efficacy of Ampelopsin (Dihydromyricetin) in tumor bearing mice will be helpful in maximizing its translational potential.

Antitumoral activity of Ficus carica L. on colorectal cancer cell lines.

In traditional medicine, Ficus carica (also known as fig) latex is recognized as a remedy with various therapeutic effects. In the present study we investigated the antitumor activity of Ficus carica extracts and latex. We evaluated the effects of increasing concentrations of Ficus carica extracts and latex on HCT-116 and HT-29 human colorectal cell proliferation using MTT assay and apoptosis induction by evaluating PARP cleavage by Western blot analysis. Peel, pulp, leaves, whole fruit and latex extracts of Ficus carica exerted significant antiproliferative effects on HCT-116 (IC50 values 239, 343, 177, 299, 206 µg/ml) and HT-29 cells (IC50 values 207, 249, 230, 261, 182 µg/ml) after 48h of treatment. Furthermore, treatment with different extracts of Ficus carica induced apoptosis in both HT-29 and HCT-116 cancer cells. Leaves and latex extracts of Ficus carica showed the strongest antiproliferative activities. Overall, our results showed that these natural products are strong apoptosis inducers which suggest their use of for therapeutic purposes.

Role of Autophagy in Breast Cancer Development and Progression: Opposite Sides of the Same Coin.

The term "autophagy", which means "self (auto) - eating (phagy)", describes a catabolic process that is evolutionarially conserved among all eukaryotes. Although autophagy is mainly accepted as a cell survival mechanism, it also modulates the process known as "type II cell death". AKT/mTOR pathway is an upstream activator of autophagy and it is tightly regulated by the ATG (autophagy-related genes) signaling cascade. In addition, wide ranging cell signaling pathways and non-coding RNAs played essential roles in the control of autophagy. Autophagy is closely related to pathological processes such as neurodegenerative diseases and cancer as well as physiological conditions. After the Nobel Prize in Physiology or Medicine 2016 was awarded to Yoshinori Ohsumi "for his discoveries of mechanisms for autophagy", there was an explosion in the field of autophagy and molecular biologists started to pay considerable attention to the mechanistic insights related to autophagy in different diseases. Since autophagy behaved dualistically, both as a cell death and a cell survival mechanism, it opened new horizons for a deeper analysis of cell type and context dependent behavior of autophagy in different types of cancers. There are numerous studies showing that the induction of autophagy mechanism will promote survival of cancer cells. Since autophagy is mainly a mechanism to keep the cells alive, it may protect breast cancer cells against stress conditions such as starvation and hypoxia. For these reasons, autophagy was noted to be instrumental in metastasis and drug resistance. In this chapter we have emphasized on role of role of autophagy in breast cancer. Additionally we have partitioned this chapter into exciting role of microRNAs in modulation of autophagy in breast cancer. We have also comprehensively summarized how TRAIL-mediated signaling and autophagy operated in breast cancer cells.

Natural Product Mediated Regulation of Death Receptors and Intracellular Machinery: Fresh from the Pipeline about TRAIL-Mediated Signaling and Natural TRAIL Sensitizers.

Rapidly developing resistance against different therapeutics is a major stumbling block in the standardization of therapy. Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)-mediated signaling has emerged as one of the most highly and extensively studied signal transduction cascade that induces apoptosis in cancer cells. Rapidly emerging cutting-edge research has helped us to develop a better understanding of the signaling machinery involved in inducing apoptotic cell death. However, excitingly, cancer cells develop resistance against TRAIL-induced apoptosis through different modes. Loss of cell surface expression of TRAIL receptors and imbalance of stoichiometric ratios of pro- and anti-apoptotic proteins play instrumental roles in rewiring the machinery of cancer cells to develop resistance against TRAIL-based therapeutics. Natural products have shown excellent potential to restore apoptosis in TRAIL-resistant cancer cell lines and in mice xenografted with TRAIL-resistant cancer cells. Significantly refined information has previously been added and continues to enrich the existing pool of knowledge related to the natural-product-mediated upregulation of death receptors, rebalancing of pro- and anti-apoptotic proteins in different cancers. In this mini review, we will set spotlight on the most recently published high-impact research related to underlying mechanisms of TRAIL resistance and how these deregulations can be targeted by natural products to restore TRAIL-mediated apoptosis in different cancers.