BP-1T, an antiangiogenic benzophenone-thiazole pharmacophore, counteracts HIF-1 signalling through p53/MDM2-mediated HIF-1α proteasomal degradation

Withaferin-A induced vimentin S56 phosphorylation dissociates NEDD9 signaling loop to regress progressive metastatic melanoma into lung adenocarcinoma

Metastasis is complex and insidious type of disease involves multiple signaling nexus, which have implications in understanding disease pathogenesis. Treatment failure for metastatic cancer is frequently high due to aggressive adaptation of cancerous cells to invade to neighboring organs. Cytoskeleton intermediate filamentous protein Vimentin and scaffolding protein Neural precursor cell expressed Developmentally Down-regulated protein 9 (NEDD9) play a key role in metastatic events by regulating multiple metastatic events. Interaction between these proteins is necessary to promote metastatic progression. Withaferin A (WFA), a natural pharamacophore, known to target Vimentin to induce antitumor potential. However exact molecular mechanism still yet to be elucidated. We hypothesize, Vimentin-NEDD9 signaling nexus is necessary for metastatic progression and targeting this interwoven signaling loop with effective pharamacophore WFA halts metastatic progression of melanoma into lung. To elucidate the same, we carried out gene expression measurement through quantitative Reverses Transcription Polymerase Chain Reaction (qRT-PCR), Immunoblot and Immunohistochemistry. Assessment of interactive signaling by Co-immunoprecipitation, Immunofluorescence, Co-localization and Proximity ligation assay. Phosphorylation studies through transfection of phospho specific mutant constructs generated through site directed mutagenesis. WFA induced cellular behavioral changes by migration, invasion assays and Immunoblot analysis. The B16F10 induced mouse metastatic melanoma model to asses NEDD9-Vimentin expression and anti-metastasis induced by WFA. The results postulates, elevated levels and interaction between NEDD9-Vimentin proteins, have positive correlation in metastatic progression of melanoma into lung in both in-vitro and in-vivo condition, establishing it as therapeutic target. Pharmacologically, WFA targets this complex by extending its activity by not only inducing specific Serine 56 phosphorylation of Vimentin, also dissociates NEDD9 signaling loop to halt Epithelial-mesenchymal transition (EMT) and subsequent metastatic events. Eventually, modulation of the relevant metastatic genes E-Cadherin, N-Cadherin, SNAIL, MMP-2 & MMP-9 resulted in regression of metastatic melanoma progression to lung. The study validates WFA induced S56 phosphorylation is necessary to abrupt the NEDD9-Vimentin metastatic signaling complex to regress aggressive metastatic melanoma. The investigation emphasized more mechanistic approach of WFA. Understanding and targeting such integrative mechanical input in the tumor microenvironment will be a better therapeutic strategy to combat metastasis.

Thiazole, Isatin and Phthalimide Derivatives Tested in vivo against Cancer Models: A Literature Review of the Last Six Years

BACKGROUND

Cancer is a disease characterized by the abnormal multiplication of cells and is the second leading cause of death in the world. The search for new effective and safe anticancer compounds is ongoing due to factors such as low selectivity, high toxicity, and multidrug resistance. Thus, heterocyclic compounds derived from isatin, thiazole and phthalimide that have achieved promising in vitro anticancer activity have been tested in vivo and in clinical trials.

OBJECTIVE

This review focused on the compilation of promising data from thiazole, isatin, and phthalimide derivatives, reported in the literature between 2015 and 2022, with in vivo anticancer activity and clinical trials.

METHODS

A bibliographic search was carried out in the PUBMED, MEDLINE, ELSEVIER, and CAPES PERIODIC databases, selecting relevant works for each pharmacophoric group with in vivo antitumor activity in the last 6 years.

RESULTS

In our study, 68 articles that fit the scope were selected and critically analyzed. These articles were organized considering the type of antitumor activity and their year of publication. Some compounds reported here demonstrated potent antitumor activity against several tumor types.

CONCLUSION

This review allowed us to highlight works that reported promising structures for the treatment of various cancer types and also demonstrated that the privileged structures thiazole, isatin and phthalimide are important in the design of new syntheses and molecular optimization of compounds with antitumor activity.

Morusinol Extracted from Morus alba Inhibits Cell Proliferation and Induces Autophagy via FOXO3a Nuclear Accumulation-Mediated Cholesterol Biosynthesis Obstruction in Colorectal Cancer

The incidence rate of colorectal cancer (CRC) has been increasing significantly in recent years, and it is urgent to develop novel drugs that have more effects for its treatment. It has been reported that many molecules extracted from the root bark of Morus alba L. (also known as Cortex Mori) have antitumor activities. In our study, we identified morusinol as a promising anticancer agent by selecting from 30 molecules extracted from Morus alba L. We found that morusinol treatment suppressed cell proliferation and promoted apoptosis of CRC cells in vitro. Besides this, we observed that morusinol induced cytoprotective autophagy. The GO analysis of differentially expressed genes from RNA-seq data showed that morusinol affected cholesterol metabolism. Then we found that key enzyme genes in the cholesterol biosynthesis pathway as well as the sterol regulatory element binding transcription factor 2 (SREBF2) were significantly downregulated. Furthermore, additional cholesterol treatment reversed the anti-CRC effect of morusinol. Interestingly, we also found that morusinol treatment could promote forkhead box O3 (FOXO3a) nuclear accumulation, which subsequently suppressed SREBF2 transcription. Then SREBF2-controlled cholesterol biosynthesis was blocked, resulting in the suppression of cell proliferation, promotion of apoptosis, and production of autophagy. The experiments in animal models also showed that morusinol significantly impeded tumor growth in mice models. Our results suggested that morusinol may be used as a candidate anticancer drug for the treatment of CRC.

Steroidal alkaloid solanidine impedes hypoxia-driven ATM phosphorylation to switch on anti-angiogenesis in lung adenocarcinoma

PURPOSE

The declined oxygen tension in the cancer cell leads to the hypoxic adaptive response and favors establishment of tumor micro environment [TEM]. The complex TME consists of interwoven hypoxic HIF-1α and DNA damage repair ATM signaling. The ATM/HIF-1α phosphorylation switch on angiogenesis and abort apoptosis. Targeting this signaling nexus would be a novel therapeutic strategy for the treatment of cancer.

BACKGROUND

Steroidal alkaloid solanidine is known for varied pharmacological role but with less molecular evidences. Our earlier findings on solanidine proven its anti-neoplastic activity by inducing apoptosis in lung cancer. In continued research, efforts have been made to establish the underlying molecular signaling in induction of DNA damage in prevailing hypoxic TME.

METHODS

The solanidine induced DNA damage was assessed trough alkali COMET assay; signaling nexus and gene expression profile analysis through IB, qRT-PCR, Gelatin Zymography, IHC, IF and ELISA. Pathophysiological modulations assessed through tube formation, migration, invasion assays. Anti-angiogenic studies through CAM, rat aorta, matrigel assays and corneal neovascularization assay. Anti-tumor activity through in-vivo DLA ascites tumor model and LLC model.

RESULTS

The results postulates, inhibition of hypoxia driven DDR proteins pATMser1981/pHIF-1αser696 by solanidine induces anti-angiogenesis. Systematic study of both non-tumorigenic and tumorigenic models in-vitro as well as in-vivo experimental system revealed the angio-regression mediated anticancer effect in lung cancer. These effects are due to the impeded expression of angiogenic mediators such as VEGF, MMP2&9 and inflammatory cytokines IL6 and TNFα to induce pathophysiological changes CONCLUSION: The study establishes new role of solanidine by targeting ATM/HIF-1α signaling to induce anti-angiogenesis for the first time. The study highlights the potentiality of plant based phytomedicine solanidine which can targets the multiple hallmarks of cancer by targeting interwoven signaling crosstalk. Such an approach through solanidine necessary to counteract heterogeneous complexity of cancer which could be nearly translated into drug.

Emerging role of interactions between tumor angiogenesis and cancer stem cells

Tumor angiogenesis and cancer stem cells (CSCs) are two major hallmarks of solid tumors. They have long received attention for their critical roles in tumor progression, metastasis and recurrence. Meanwhile, plenty of evidence indicates the close association between CSCs and tumor vasculature. CSCs are proven to promote tumor angiogenesis, and the highly vascularized tumor microenvironment further maintains CSCs growth in return, thereby forming a hard-breaking vicious circle to promote tumor development. Hence, though monotherapy targeting tumor vasculature or CSCs has been extensively studied over the past decades, the poor prognosis has been limiting the clinical application. This review summarizes the crosstalk between tumor vasculature and CSCs with emphasis on small-molecule compounds and the associated biological signaling pathways. We also highlight the importance of linking tumor vessels to CSCs to disrupt the CSCs-angiogenesis vicious circle. More precise treatment regimens targeting tumor vasculature and CSCs are expected to benefit future tumor treatment development.

The Ubiquitin-Proteasome System in Tumor Metabolism

Metabolic reprogramming, which is considered a hallmark of cancer, can maintain the homeostasis of the tumor environment and promote the proliferation, survival, and metastasis of cancer cells. For instance, increased glucose uptake and high glucose consumption, known as the "Warburg effect," play an essential part in tumor metabolic reprogramming. In addition, fatty acids are harnessed to satisfy the increased requirement for the phospholipid components of biological membranes and energy. Moreover, the anabolism/catabolism of amino acids, such as glutamine, cystine, and serine, provides nitrogen donors for biosynthesis processes, development of the tumor inflammatory environment, and signal transduction. The ubiquitin-proteasome system (UPS) has been widely reported to be involved in various cellular biological activities. A potential role of UPS in the metabolic regulation of tumor cells has also been reported, but the specific regulatory mechanism has not been elucidated. Here, we review the role of ubiquitination and deubiquitination modification on major metabolic enzymes and important signaling pathways in tumor metabolism to inspire new strategies for the clinical treatment of cancer.

Sonodynamic therapy suppresses matrix collagen degradation in vulnerable atherosclerotic plaque by modulating caspase 3 - PEDF/HIF-1α - MMP-2/MMP-9 signaling in macrophages

BACKGROUND

The rupture of vulnerable atherosclerotic plaque is the main cause of acute ischemic vascular events, and is characterized by pathological degradation of matrix collagen in the fibrous cap. In a previous study, we reported that 5-aminolevulinic acid-mediated sonodynamic therapy suppressed collagen degradation in rabbit plaque. However, the underlying molecular mechanism has yet to be fully elucidated.

METHODS

We applied sinoporphyrin sodium-mediated sonodynamic therapy (DVDMS-SDT) to balloon-denuded rabbit and apolipoprotein E-deficient (ApoE-/-) mouse models to observe collagen content in plaque. Cultured human THP-1 and mouse peritoneal macrophage-derived foam cells were used for in vitro mechanistic studies.

RESULTS

We observed that DVDMS-SDT decreased plaque area and increased the percentages of collagen and smooth muscle cells and reduced the percentage of macrophages in rabbit and ApoE-/- mouse advanced plaques. In vitro, DVDMS-SDT modulated the caspase 3-pigment epithelium-derived factor/hypoxia-inducible factor-1α (PEDF/HIF-1α)-matrix metalloprotease-2/9 (MMP-2/MMP-9) signaling in macrophage foam cells.

CONCLUSIONS

Our findings show that DVDMS-SDT effectively inhibits matrix collagen degradation in advanced atherosclerotic plaque by modulating caspase 3-PEDF/HIF-1α-MMP-2/MMP-9 signaling in macrophage foam cells and therefore represents a suitable and promising clinical regimen to stabilize vulnerable plaques.

A systems biology investigation of curcumin potency against TGF-β-induced EMT signaling in lung cancer

Curcumin (diferuloylmethane) is bioactive phenolic compound which exerts diverse antimetastatic effect. Several studies have reported the antimetastatic effect of curcumin by its ability to modulate the epithelial-to-mesenchymal transition (EMT) process in different cancers, but underlying molecular mechanism is poorly understood. EMT is a highly conserved biological process in which epithelial cells acquire mesenchymal-like characteristics by losing their cell-cell junctions and polarity. As a consequence, deviation in cellular mechanism leads to cancer metastasis and thereby death. In this perspective, we explored the antimetastatic potential and mechanism of curcumin on the EMT process by establishing in vitro EMT model in lungs cancer (A549) cells induced by TGF-β1. Our results showed that curcumin mitigates EMT by regulating the expression of crucial mesenchymal markers such as MMP2, vimentin and N-cadherin. Besides, the transcriptional analysis revealed that the curcumin treatment differentially regulated the expression of 75 genes in NanoString nCounter platform. Further protein-protein interaction network and clusters analysis of differentially expressed genes revealed their involvement in essential biological processes that plays a key role during EMT transition. Altogether, the study provides a comprehensive overview of the antimetastatic potential of curcumin in TGF-β1-induced EMT in lung cancer cells.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-022-03360-7.

Vitamin C-induced competitive binding of HIF-1α and p53 to ubiquitin E3 ligase CBL contributes to anti-breast cancer progression through p53 deacetylation

Vitamin C (VC), in regard to its effectiveness against tumors, has had a controversial history in cancer treatment. However, the anticancer mechanisms of VC are not fully understood. Here, we reported that VC exerted an anticancer effect on cancer cell and xenograft models via inhibiting HIF-1α-dependent cell proliferation and promoting p53-dependent cell apoptosis. To be specific, VC modulated the competitive binding of HIF-1α and p53 to their common E3 ubiquitin ligase CBL, thereby inhibiting tumorigenesis. Moreover, VC treatment activated SIRT1, resulting in p53 deacetylation and CBL-p53 complex dissociation, which in turn facilitated CBL recruitment of HIF-1α for ubiquitination in a proteasome-dependent manner. Altogether, our results provided a mechanistic rationale for exploring the therapeutic use of VC in cancer therapy.

PFKFB3 regulates cancer stemness through the hippo pathway in small cell lung carcinoma

PFKFB3 (6-phosphofructo-2-kinase) is the rate-limiting enzyme of glycolysis and is overexpressed in several human cancers that are associated with poor prognosis. High PFKFB3 expression in cancer stem cells promotes glycolysis and survival in the tumor microenvironment. Inhibition of PFKFB3 by the glycolytic inhibitor PFK158 and by shRNA stable knockdown in small cell lung carcinoma (SCLC) cell lines inhibited glycolysis, proliferation, spheroid formation, and the expression of cancer stem cell markers CD133, Aldh1, CD44, Sox2, and ABCG2. These factors are also associated with chemotherapy resistance. We found that PFK158 treatment and PFKFB3 knockdown enhanced the ABCG2-interacting drugs doxorubicin, etoposide, and 5-fluorouracil in reducing cell viability under conditions of enriched cancer stem cells (CSC). Additionally, PFKFB3 inhibition attenuated the invasion/migration of SCLC cells by downregulating YAP/TAZ signaling while increasing pLATS1 via activation of pMST1 and NF2 and by reducing the mesenchymal protein expression. PFKFB3 knockdown and PFK158 treatment in a H1048 SCLC cancer stem cell-enriched mouse xenograft model showed significant reduction in tumor growth and weight with reduced expression of cancer stem cell markers, ABCG2, and YAP/TAZ. Our findings identify that PFKFB3 is a novel target to regulate cancer stem cells and its associated therapeutic resistance markers YAP/TAZ and ABCG2 in SCLC models.

Molecular and cellular regulatory roles of sirtuin protein

Sirtuins (SIRT) are unique posttranslational modification enzymes that utilize NAD + as co-substrate to remove acyl groups from lysine residues. SIRT act on variety of substrates and impact major metabolic process. All seven members of SIRT family are unique and targets wide range of cellular proteins in nucleus, cytoplasm, and mitochondria for post-translational modification by acetylation (SIRT1, 2, 3, and 5) or ADP-ribosylation (SIRT4 and 6). Each member of SIRT family is distinct. SIRT2 was first to be discovered that incited research on mammalian SIRT. Enzymatic activities of SIRT 4 are yet to be elucidated while only SIRT7 is localized in nucleoli that govern the transcription of RNA polymerase I. SIRT 5 and 6 exhibit weakest deacetylase activity. Out of all SIRT analogs, SIRT1 is identified as nutrient sensor. Increased expression of only SIRT3 is linked with longevity in humans. Since SIRT is regulated by the bioenergetic state of the cell, nutrition impacts it but very few studies about diet-mediated effect on SIRT are reported. The present review elaborates distribution, specific biological role and prominent effect of all SIRT on vital human tissue along with highlighting need to trace molecular mechanisms and identifying foods that may augment it beneficially.

Anti-neoplastic pharmacophore benzophenone-1 coumarin (BP-1C) targets JAK2 to induce apoptosis in lung cancer

Reigning of the abnormal gene activation associated with survival signalling in lung cancer leads to the anomalous growth and therapeutic failure. Targeting specific cell survival signalling like JAK2/STAT3 nexus has become a major focus of investigation to establish a target specific treatment. The 2-bromobenzoyl-4-methylphenoxy-acetyl hydra acetyl Coumarin (BP-1C), is new anti-neoplastic agent with apoptosis inducing capacity. The current study was aimed to develop antitumor phramacophore, BP-1C as JAK2 specific inhibitor against lung neoplastic progression. The study validates and identifies the molecular targets of BP-1C induced cell death. Cell based screening against multiple cancer cell lines identified, lung adenocarcinoma as its specific target through promotion of apoptosis. The BP-1C is able to induce, specific hall marks of apoptosis and there by conferring anti-neoplastic activity. Validation of its molecular mechanism, identified, BP-1C specifically targets JAK2^Tyr1007/1008 phosphorylation, and inhibits its downstream STAT3^Tyr705 signalling pathway to induce cell death. As a consequence, modulation in Akt/Src survival signal and altered expression of interwoven apoptotic genes were evident. The results were reproducible in an in-vivo LLC tumor model and in-ovo xenograft studies. The computational approaches viz, drug finger printing confers, BP-1C as novel class JAK2 inhibitor and molecular simulations studies assures its efficiency in binding with JAK2. Overall, BP-1C is a novel JAK2 inhibitor with experimental evidence and could be effectively developed into a promising drug for lung cancer treatment.

Targeted Inhibition of Anti-Inflammatory Regulator Nrf2 Results in Breast Cancer Retardation In Vitro and In Vivo

Nuclear factor erythroid-2 related factor-2 (Nrf2) is an oxidative stress-response transcriptional activator that promotes carcinogenesis through metabolic reprogramming, tumor promoting inflammation, and therapeutic resistance. However, the extension of Nrf2 expression and its involvement in regulation of breast cancer (BC) responses to chemotherapy remain largely unclear. This study determined the expression of Nrf2 in BC tissues (n = 46) and cell lines (MDA-MB-453, MCF-7, MDA-MB-231, MDA-MB-468) with diverse phenotypes. Immunohistochemical (IHC)analysis indicated lower Nrf2 expression in normal breast tissues, compared to BC samples, although the difference was not found to be significant. However, pharmacological inhibition and siRNA-induced downregulation of Nrf2 were marked by decreased activity of NADPH quinone oxidoreductase 1 (NQO1), a direct target of Nrf2. Silenced or inhibited Nrf2 signaling resulted in reduced BC proliferation and migration, cell cycle arrest, activation of apoptosis, and sensitization of BC cells to cisplatin in vitro. Ehrlich Ascites Carcinoma (EAC) cells demonstrated elevated levels of Nrf2 and were further tested in experimental mouse models in vivo. Intraperitoneal administration of pharmacological Nrf2 inhibitor brusatol slowed tumor cell growth. Brusatol increased lymphocyte trafficking towards engrafted tumor tissue in vivo, suggesting activation of anti-cancer effects in tumor microenvironment. Further large-scale BC testing is needed to confirm Nrf2 marker and therapeutic capacities for chemo sensitization in drug resistant and advanced tumors.

Targeting HIF-1α by newly synthesized Indolephenoxyacetamide (IPA) analogs to induce anti-angiogenesis-mediated solid tumor suppression

BACKGROUND

Hypoxic microenvironment is a common feature of solid tumors, which leads to the promotion of cancer. The transcription factor, HIF-1α, expressed under hypoxic conditions stimulates tumor angiogenesis, favoring HIF-1α as a promising anticancer agent. On the other hand, synthetic Indolephenoxyacetamide derivatives are known for their pharmacological potentiality. With this background here, we have synthesized, characterized, and validated the new IPA (8a-n) analogs for anti-tumor activity.

METHODS

The new series of IPA (8a-n) were synthesized through a multi-step reaction sequence and characterized based on the different spectroscopic analysis FT-IR, ¹H, ¹³C NMR, mass spectra, and elemental analyses. Cell-based screening of IPA (8a-n) was assessed by MTT assay. Anti-angiogenic efficacy of IPA (8k) validated through CAM, Rat corneal, tube formation and migration assay. The underlying molecular mechanism is validated through zymogram and IB studies. The in vivo anti-tumor activity was measured in the DLA solid tumor model.

RESULTS

Screening for anti-proliferative studies inferred, IPA (8k) is a lead molecule with an IC₅₀ value of _˜5 μM. Anti-angiogenic assays revealed the angiopreventive activity through inhibition of HIF-1α and modulation downstream regulatory genes, VEGF, MMPs, and P53. The results are confirmative in an in vivo solid tumor model.

CONCLUSION

The IPA (8k) is a potent anti-proliferative molecule with anti-angiogenic activity and specifically targets HIF1α, thereby modulates its downstream regulatory genes both in vitro and in vivo. The study provides scope for new target-specific drug development against HIF-1α for the treatment of solid tumors.

The role of ubiquitination and deubiquitination in cancer metabolism

Metabolic reprogramming, including enhanced biosynthesis of macromolecules, altered energy metabolism, and maintenance of redox homeostasis, is considered a hallmark of cancer, sustaining cancer cell growth. Multiple signaling pathways, transcription factors and metabolic enzymes participate in the modulation of cancer metabolism and thus, metabolic reprogramming is a highly complex process. Recent studies have observed that ubiquitination and deubiquitination are involved in the regulation of metabolic reprogramming in cancer cells. As one of the most important type of post-translational modifications, ubiquitination is a multistep enzymatic process, involved in diverse cellular biological activities. Dysregulation of ubiquitination and deubiquitination contributes to various disease, including cancer. Here, we discuss the role of ubiquitination and deubiquitination in the regulation of cancer metabolism, which is aimed at highlighting the importance of this post-translational modification in metabolic reprogramming and supporting the development of new therapeutic approaches for cancer treatment.

Oxygen sensing decoded: a Nobel concept in biology

Oxygen is essential to most organisms as it is a necessity for aerobic metabolism and energy production. Too much or too little oxygen can be deadly, such that mechanisms for fast and titrated response to changing oxygen levels are crucial. These mechanisms have evolved from the studies of Gregg L. Semenza, William G. Kaelin and Peter J. Ratcliffe. It is through the work of their three laboratories, performed in the 1990s, that the cellular oxygen sensing mechanisms have been decoded. Their discoveries have had major impact for innovation in medicine, especially in the field of angiogenesis research, where oxygen sensing and its consequences have led to enhanced insight in vascular development and strategies for combating angiogenic diseases. On October 7, the Nobel Assembly in Stockholm announced at the Karolinska Institute that the Nobel Prize for Medicine 2019 is jointly awarded to these three scientists for their seminal discoveries on how cells sense and respond to oxygen.

Sonodynamic Therapy Suppresses Neovascularization in Atherosclerotic Plaques via Macrophage Apoptosis-Induced Endothelial Cell Apoptosis

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DVDMS-SDT reduces neovascularization in late-stage atherosclerotic lesions in both rabbit and mouse models.

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DVDMS-SDT enhances macrophage foam cell apoptosis, which in turn induces neovessel endothelial cell apoptosis and inhibits its proliferation, migration, and tubulogenesis, termed apoptosis-induced apoptosis.

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Mechanistically, DVDMS-SDT induces macrophage foam cell apoptosis via mitochondrial-caspase pathway, which activates caspase 3 to cleave SP-1, leading to the reduction of HIF-1α and VEGF-A.

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In the pilot translational study, DVDMS-SDT reduces plaque angiogenesis and inhibits vessel inflammation.

During atherosclerosis plaque progression, pathological intraplaque angiogenesis leads to plaque rupture accompanied by thrombosis, which is probably the most important cause of arteries complications such as cerebral and myocardial infarction. Even though few treatments are available to mitigate plaque rupture, further investigation is required to develop a robust optimized therapeutic method. In this study using rabbit and mouse atherosclerotic models, sinoporphyrin sodium (DVDMS)-mediated sonodynamic therapy reduced abnormal angiogenesis and plaque rupture. Briefly, DVDMS is injected to animals, and then the plaque was locally exposed to pulse ultrasound for a few minutes. Furthermore, a small size clinical trial was conducted on patients with atherosclerosis. Notably, a significant reduction of arterial inflammation and angiogenesis was recorded following a short period of DVDMS-mediated sonodynamic therapy treatment. This beneficial outcome was almost equivalent to the therapeutic outcome after 3-month intensive statin treatment.

DUSP1 recuses diabetic nephropathy via repressing JNK-Mff-mitochondrial fission pathways

Excessive mitochondrial fission has been identified as the pathogenesis of diabetic nephropathy (DN), although the upstream regulatory signal for mitochondrial fission activation in the setting of DN remains unknown. In the current study, we found that dual-specificity protein phosphatase-1 (DUSP1) was actually downregulated by chronic hyperglycemia stimulus. Lower DUSP1 expression was associated with glucose metabolism disorder, renal dysfunction, kidney hypertrophy, renal fibrosis, and glomerular apoptosis. At the molecular level, defective DUSP1 expression activated JNK pathway, and the latter selectively opened mitochondrial fission by modulating mitochondrial fission factor (Mff) phosphorylation. Excessive Mff-related mitochondrial fission evoked mitochondrial oxidative stress, promoted mPTP opening, exacerbated proapoptotic protein leakage into the cytoplasm, and finally initiated mitochondria-dependent cellular apoptosis in the setting of diabetes. However, overexpression of DUSP1 interrupted Mff-related mitochondrial fission, reducing hyperglycemia-mediated mitochondrial damage and thus improving renal function. Overall, we have shown that DUSP1 functions as a novel malefactor in diabetic renal damage that mediates via modifying Mff-related mitochondrial fission. Thus, finding strategies to regulate the balance of the DUSP1-JNK-Mff signaling pathway and mitochondrial homeostasis may be a therapeutic target for treating diabetic nephropathy in clinical practice.

Matrine has pro-apoptotic effects on liver cancer by triggering mitochondrial fission and activating Mst1-JNK signalling pathways

Mitochondrial homeostasis is closely associated with liver cancer progression via multiple mechanisms and is also a potential tumour-suppressive target in clinical practice. However, the role of mitochondrial fission in liver cancer cell viability has not been adequately investigated. Matrine, a type of alkaloid isolated from Sophoraflavescens, has been widely used to treat various types of cancer. However, the molecular effect of matrine on mitochondrial homeostasis is unclear. Therefore, the aim of the current study was to determine the role of mitochondrial fission in cell apoptosis, viability, migration and proliferation of HepG2 cells in vitro. The effect of matrine on mitochondrial fission and its mechanism were also explored. The results of our study showed that HepG2 cells treated with matrine had reduced viability, an increased apoptotic rate, a blunted migratory response, and impaired proliferation capacity. At the molecular level, matrine treatment activated mitochondrial fission, which promoted mitochondrial dysfunction, caused cellular oxidative stress, disrupted cellular energy metabolism and initiated cell apoptotic pathways. However, blockade of mitochondrial fission abolished the deleterious effects of matrine on HepG2 cells. Further, we demonstrated that the Mst1-JNK signalling axis was required for matrine-modulated mitochondrial fission. Matrine-mediated mitochondrial dysfunction was reversed by inhibiting Mst1-JNK pathways. Together, our results demonstrated that mitochondrial fission could be a potential upstream tumour-suppressive signal for liver cancer by modifying mitochondrial function and cell death. By contrast, matrine exerted an anticancer function in liver cancer by activating mitochondrial fission mediated by Mst1-JNK pathways.

Mst1 promotes cardiac ischemia-reperfusion injury by inhibiting the ERK-CREB pathway and repressing FUNDC1-mediated mitophagy

Cardiac ischemia-reperfusion (I/R) injury results mainly from mitochondrial dysfunction and cardiomyocyte death. Mitophagy sustains mitochondrial function and exerts a pro-survival effect on the reperfused heart tissue. Mammalian STE20-like kinase 1 (Mst1) regulates chronic cardiac metabolic damage and autophagic activity, but its role in acute cardiac I/R injury, especially its effect on mitophagy, is unknown. The aim of this study is to explore whether Mst1 is involved in reperfusion-mediated cardiomyocyte death via modulation of FUN14 domain containing 1 (FUNDC1)-related mitophagy. Our data indicated that Mst1 was markedly increased in reperfused hearts. However, genetic ablation of Mst1 in Mst1-knockout (Mst1-KO) mice significantly reduced the expansion of the cardiac infarction area, maintained myocardial function and abolished I/R-mediated cardiomyocyte death. At the molecular level, upregulation of Mst1 promoted ROS production, reduced mitochondrial membrane potential, facilitated the leakage of mitochondrial pro-apoptotic factors into the nucleus, and activated the caspase-9-related apoptotic pathway in reperfused cardiomyocytes. Mechanistically, Mst1 activation repressed FUNDC1 expression and consequently inhibited mitophagy. However, deletion of Mst1 was able to reverse FUNDC1 expression and thus re-activate protective mitophagy, effectively sustaining mitochondrial homeostasis and blocking mitochondrial apoptosis in reperfused cardiomyocytes. Finally, we demonstrated that Mst1 regulated FUNDC1 expression via the MAPK/ERK-CREB pathway. Inhibition of the MAPK/ERK-CREB pathway prevented FUNDC1 activation caused by Mst1 deletion. Altogether, our data confirm that Mst1 deficiency sends a pro-survival signal for the reperfused heart by reversing FUNDC1-related mitophagy and thus reducing cardiomyocyte mitochondrial apoptosis, which identifies Mst1 as a novel regulator for cardiac reperfusion injury via modulation of mitochondrial homeostasis.

Current insights and future perspectives of hypoxia-inducible factor-targeted therapy in cancer

Hypoxia-inducible factors (HIFs) are transcription factors that are expressed in the hypoxic tumor microenvironment. They are involved in the cellular adaptations by improving the metabolism of glucose and enhance the expression of vascular endothelial growth factor, platelet-derived growth factor and angiopoietin, thereby they play a pivotal role in the angiogenesis. Hypoxia can increase the expression of nuclear factor-kappa B which promotes the pro-inflammatory status. Abnormally high angiogenesis, inflammation, antiapoptosis and anaerobic glycolysis can augment the progression and metastasis of tumor. Hence, HIFs remain one of the promising antiangiogenic agents as well as a direct target for interfering with the energetic of cancer cells in order to regulate the tumor growth. Previous studies found agents like topotecan, acriflavine and benzophenone-1B etc. to block the HIF-α mediated angiogenesis. The effect is mediated through interfering any one of the processes in the activation of HIF such as nuclear translocation of HIF-1α; dimerization of HIF-1α with β in the nucleus; HIF-1α/HIF-2α mediated induction of VEGF or translation of HIF-1α mRNA. Despite the experimental studies on the inhibitory molecules of HIFs, none of them are available for the clinical use. This review article discusses the recent update on the HIF-targeted therapy in cancer.

LATS2 promotes apoptosis in non-small cell lung cancer A549 cells via triggering Mff-dependent mitochondrial fission and activating the JNK signaling pathway

LATS2 is a classical tumor suppressor that affects non-small cell lung cancer proliferation and mobilization. However, its role in lung cancer cell apoptosis is unknown. The aim of our study is to explore whether LATS2 activates mitochondria-related apoptosis in lung cancer cells. In the present study, A549 non-small cell lung cancer cells were transfected with a LATS2 adenovirus to induce LATS2 overexpression. Cell apoptosis was evaluated via the MTT assay, TUNEL staining, western blotting, trypan blue staining and ELISA. Mitochondrial function was measured using an immunofluorescence assay, western blotting and ELISA. The results demonstrated that LATS2 was downregulated in A549 lung cancer cells. Overexpression of LATS2 induced A549 cell apoptosis via activating mitochondrial fission. Subsequently, we confirmed that LATS2 modulated mitochondrial fission via the JNK-Mff signaling pathway. Inhibition of the JNK pathway and/or knockdown of Mff abolished the pro-apoptotic effect of LATS2 on A549 cells. Taken together, our results identified LATS2 as a classical tumor suppressor of lung cancer via triggering mitochondrial fission and activating the JNK-Mff signaling pathway. Our results lay the foundation for detailed study of the molecular mechanisms of LATS2 overexpression and regulation of mitochondrial fission for lung cancer treatment.

Sirtuin‑1 protects hair follicle stem cells from TNFα-mediated inflammatory stress via activating the MAPK-ERK-Mfn2 pathway

OBJECTIVE

Stem cell transplantation is a promising tool to treat burn injuries. However, the inflammatory microenvironment in damaged skin limits the efficiency of stem cell-based therapy via poorly understood mechanisms. The aim of our study is to explore the contribution and mechanism of Sirtuin-1 (Sirt1) in TNFα-mediated inflammatory stress in hair follicle stem cells (HFSCs).

METHODS

Cellular viability was determined using the MTT assay, TUNEL staining, western blot analysis and LDH release assay. Adenovirus-loaded Sirt1 was transduced into HFSCs to overexpress Sirt1 in the presence of TNFα. Mitochondrial function was determined using JC-1 staining, mitochondrial ROS staining, immunofluorescence staining and western blotting.

RESULTS

Sirt1 was downregulated in response to the TNFα treatment. Additionally, TNFα stress reduced the viability, mobility and proliferation of HFSCs, and these effects were reversed by the overexpression of Sirt1. At the molecular level, Sirt1 overexpression attenuated TNFα-mediated mitochondrial damage, as evidenced by increased mitochondrial energy metabolism, decreased mitochondrial ROS generation, stabilized mitochondrial potential and blockage of the mitochondrial apoptotic pathway. Furthermore, Sirt1 modulated mitochondrial homeostasis by activating the MAPK-ERK-Mfn2 axis; inhibition of this pathway abrogated the protective effects of Sirt1 on HFSC survival, migration and proliferation.

SIGNIFICANCE

Based on our results, the inflammatory stress-mediated HFSC injury may be associated with a decrease in Sirt1 expression and subsequent mitochondrial dysfunction. Accordingly, strategies designed to enhance Sirt1 expression would be an effective approach to enhance the survival of HFSCs in the inflammatory microenvironment.

RETRACTED: DUSP1 alleviates cerebral ischaemia reperfusion injury via inactivating JNK-Mff pathways and repressing mitochondrial fission

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor-in-Chief. The article titled “DUSP1 alleviates cerebral ischaemia reperfusion injury via inactivating JNK-Mff pathways and repressing mitochondrial fission” is a near duplicate of a previously published manuscript titled “DUSP1 alleviates cardiac ischemia/reperfusion injury by suppressing the Mff-required mitochondrial fission and Bnip3-related mitophagy via the JNK pathways. Redox Biology. 2018;14:576-587.”

Sirt3 attenuates post-infarction cardiac injury via inhibiting mitochondrial fission and normalization of AMPK-Drp1 pathways

Mitochondrial damage is involved in the pathogenesis of post-infarction cardiac injury. However, the upstream regulators of mitochondrial damage have not yet been identified. The aim of our study is to explore the role of Sirt3 in post-infarction cardiac injury with a particular focus on mitochondrial fission and AMPK-Drp1 pathways. Our results indicated that Sirt3 was downregulated in the progression of post-infarction cardiac injury. Overexpression of Sirt3 attenuated cardiac fibrosis, sustained myocardial function, inhibited the inflammatory response, and reduced cardiomyocyte death. Functional studies illustrated that chronic post-infarction cardiac injury was characterized by increased mitochondrial fission, which triggered mitochondrial oxidative stress, metabolic disorders, mitochondrial potential reduction and caspase-9 apoptosis in cardiomyocytes. However, Sirt3 overexpression attenuated mitochondrial fission and thus preserved mitochondrial homeostasis and cardiomyocyte viability. Furthermore, our results confirmed that Sirt3 repressed mitochondrial fission via normalizing AMPK-Drp1 pathways. Inhibition of AMPK activity re-activated Drp1 and thus abrogated the inhibitory effect of Sirt3 on mitochondrial fission. Altogether, our results indicate that Sirt3 enhancement could be an effective approach to retard the development of post-infarction cardiac injury via disrupting mitochondrial fission and normalizing the AMPK-Drp1 axis.

NR4A1 Promotes Cerebral Ischemia Reperfusion Injury by Repressing Mfn2-Mediated Mitophagy and Inactivating the MAPK-ERK-CREB Signaling Pathway

Mitochondrial dysfunction has been acknowledged as the key pathogenic mechanism in cerebral ischemia-reperfusion (IR) injury. Mitophagy is the protective system used to sustain mitochondrial homeostasis. However, the upstream regulator of mitophagy in response to brain IR injury is not completely understood. Nuclear receptor subfamily 4 group A member 1 (NR4A1) has been found to be associated with mitochondrial protection in a number of diseases. The aim of our study is to explore the functional role of NR4A1 in cerebral IR injury, with a particular focus on its influence on mitophagy. Wild-type mice and NR4A1-knockout mice were used to generate cerebral IR injury in vivo. Mitochondrial function and mitophagy were detected via immunofluorescence assays and western blotting. Cellular apoptosis was determined via MTT assays, caspase-3 activity and western blotting. Our data revealed that NR4A1 was significantly increased in the reperfused brain tissues. Genetic ablation of NR4A1 reduced the cerebral infarction area and repressed neuronal apoptosis. The functional study demonstrated that NR4A1 modulated cerebral IR injury by inducing mitochondrial damage. Higher NR4A1 promoted mitochondrial potential reduction, evoked cellular oxidative stress, interrupted ATP generation, and initiated caspase-9-dependent apoptosis. Mechanistically, NR4A1 induced mitochondrial damage by disrupting Mfn2-mediated mitophagy. Knockdown of NR4A1 elevated Mfn2 expression and therefore reversed mitophagic activity, sending a prosurvival signal for mitochondria in the setting of cerebral IR injury. Further, we demonstrated that NR4A1 modulated Mfn2 expression via the MAPK-ERK-CREB signaling pathway. Blockade of the ERK pathway could abrogate the permissive effect of NR4A1 deletion on mitophagic activation, contributing to neuronal mitochondrial apoptosis. Overall, our results demonstrate that the pathogenesis of cerebral IR injury is closely associated with a drop in protective mitophagy due to increased NR4A1 through the MAPK-ERK-CREB signaling pathway.

Consensus guidelines for the use and interpretation of angiogenesis assays

The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference.

Therapeutic effect of Sirtuin 3 on ameliorating nonalcoholic fatty liver disease: The role of the ERK-CREB pathway and Bnip3-mediated mitophagy

Increased mitochondrial damage is related to the progression of a diet-induced nonalcoholic fatty liver disease. The aim of our study is to investigate the role of Sirtuin 3 (Sirt3) in treating nonalcoholic fatty liver disease with a focus on mitophagy and the ERK-CREB pathway. Our data indicated that Sirt3 was downregulated in liver tissue in response to chronic HFD treatment. Interestingly, re-introduction of Sirt3 protected hepatic function, attenuated liver fibrosis, alleviated the inflammatory response, and prevented hepatocyte apoptosis. Molecular investigations demonstrated that lipotoxicity was associated with an increase in mitochondrial apoptosis as evidenced by reduced mitochondrial potential, augmented ROS production, increased cyt-c leakage into the nucleus, and activated caspase-9 apoptotic signalling. Additionally, Sirt3 overexpression protected hepatocytes against mitochondrial apoptosis via promoting Bnip3-required mitophagy. Functional studies showed that Sirt3 reversed Bnip3 expression and mitophagy activity via the ERK-CREB signalling pathway. Blockade of the ERK-CREB axis repressed the promotive effects of Sirt3 on Bnip3 activation and mitophagy augmentation, finally negating the anti-apoptotic influences of Sirt3 on hepatocytes in the setting of high-fat-stress. Collectively, our data show that high-fat-mediated liver damage is associated with Sirt3 downregulation, which is followed by ERK-CREB pathway inactivation and Bnip3-mediated inhibition of mitophagy, causing hepatocytes to undergo mitochondria-dependent cell death. Based on this, strategies for enhancing Sirt3 activity and activating the ERK-CREB-Bnip3-mitophagy pathways could be used to treat nonalcoholic fatty liver disease.

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Sirt3 overexpression prevents diet-mediated fatty liver disease.

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Sirt3 blocks hepatocyte mitochondrial apoptosis in the setting of high-fat injury.

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Bnip3-mediated mitophagy protects mitochondria against high-fat-mediated damage.

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Sirt3 controls Bnip3-mediated mitophagy via the ERK-CREB signalling pathway.

Loss of P53 regresses cardiac remodeling induced by pressure overload partially through inhibiting HIF1α signaling in mice

The tumor suppressor p53 is recognized as the guardian of the genome in cell cycle and cell death. P53 expression increases as cardiac hypertrophy worsens to heart failure, suggesting that p53 may play important role in cardiac remodeling. In the present study, deletion of p53 in the mice heart would ameliorate cardiac hypertrophy induced by pressure overload. The role of p53 on heart was investigated using in vivo models. Cardiac hypertrophy in mice was induced by transverse aortic banding surgery. The extent of cardiac hypertrophy was examined by echocardiography, as well as pathological and molecular analyses of heart tissue. Global knockout of p53 in the mice reduced the hypertrophic response and markedly reduced cardiac apoptosis, and fibrosis. Ejection fraction of heart was also improved in hearts without p53 in response to pressure overload. Protein determination further suggested loss of p53 expression markedly increased Hypoxia-inducible factor 1-alpha (HIF1α) and vascular endothelial growth factor (VEGF) expression. The study indicated p53 deteriorated cardiac functions and cardiac hypertrophy, apoptosis, and fibrosis by partially inhibition of HIF1α and VEGF.

The critical role of novel benzophenone analogs on tumor growth inhibition targeting angiogenesis and apoptosis

In modern biology, one of the major topics of importance is progress in anti-cancer drugs with specific targets. The angiopreventive and in vitro tumor inhibition activities of novel synthetic benzophenone analogs have been investigated intensively and explored in a very systematic way. Novel benzophenone analogs (9a-d and 10a-d) substituted with methyl, chloro and fluoro groups at different positions on an identical chemical backbone and incorporating variations in the number of substituents have been synthesized in a multistep process and characterized. In this study, we further evaluate the newly synthesized compounds for their cytotoxic and anti-proliferative effects against A549, HeLa and MCF-7 cells. The potent lead compound was further assessed for anti-angiogenic effects. Through the structure-activity relationship, we found that an increase in the number of methyl, chloro and fluoro groups in a benzophenone ring on compound 9d resulted in higher potency compared to other compounds. Tumor inhibition was notably promoted, and this was reflected in effects on neovessel formation in in vivo systems, such as the CAM. Compound 9d interacts with rVEGF through hydrogen bonds in silico, thereby down-regulating the expression of VEGF in angiogenesis. From our investigation, it is suggested on the basis of clonogenesis and cell migration assays that compound 9d has the potency to exhibit prolonged activity against cancer progression, through cell cycle arrest at the G2/M phase. In addition, compound 9d inhibits A549 cells through caspase-activated DNase-mediated apoptosis.

The tumor antagonistic steroidal alkaloid Solanidine prompts the intrinsic suicidal signal mediated DFF-40 nuclear import and nucleosomal disruption

Aim Deformity in the cellular homeostatic event associated with cell survival and apoptosis are committing factors for carcinogenesis. Interventions of these events by pharmacologically active agent gain predominance in cancer treatment. In current investigation Solanidine, a steroidal alkaloid was evaluated on tumorigenesis by targeting death signal using multiple tumor cells and model systems.

MAIN METHODS

Anti-proliferative effect was evaluated using cytotoxic studies. Prolonged cytotoxic effect of Solanidine was examined by colony formation assay. Exhibition of apoptotic hallmark induced by Solanidine was examined using FACS analysis, Annexin-V staining, Acridine orange staining, TUNEL assay. Altered gene expression was evaluated using Immunoblot, Immunofluorescence and Immunohistochemistry technique. In-vitro results were revalidated in EAC solid tumor and CAM xenograft model.

KEY FINDINGS

Solanidine exerts its potential effect in a target specific manner. The cytotoxic/anticlonogenic activity was due to induction of typical cellular apoptotic hallmarks and cell cycle blockage at S-G2/M phase. The molecular events underlying this effect is through activation of intrinsic pathway via Bax, Bad and Cytochrome c activation by neutralizing Bcl-2 expression, along with downregulated PI3K/Akt survival signal. As a consequence, downstream pro apoptogenic gene, active Caspase-3 was over expressed by Solanidine to cleave its substrate PARP and promotes nuclear import of DFF-40. Anti-carcinogenic aptitude was further confirmed by murine solid tumors and in-vivo CAM xenograft studies.

SIGNIFICANCE

Solanidine emerged as active molecule against tomorigenesis by activating nuclear import of DFF-40 mediated nucleosomal disruption and cell demise. It can be developed as a potential apoptogenic small molecule for cancer therapy.

Immunomodulatory glc/man-directed Dolichos lablab lectin (DLL) evokes anti-tumour response in vivo by counteracting angiogenic gene expressions

Neovascularization and jeopardized immunity has been critically emphasized for the establishment of malignant progression. Lectins are the diverse class of carbohydrate interacting proteins, having great potential as immunopotentiating and anti-cancer agents. The present investigation sought to demonstrate the anti-proliferative activity of Dolichos lablab lectin (DLL) encompassing immunomodulatory attributes. DLL specific to glucose and mannose carbohydrate moieties has been purified to homogeneity from the common dietary legume D. lablab. Results elucidated that DLL agglutinated blood cells non-specifically and displayed striking mitogenicity to human and murine lymphocytes in vitro with interleukin (IL)-2 production. The DLL-conditioned medium exerted cytotoxicity towards malignant cells and neoangiogenesis in vitro. Similarly, in-vivo anti-tumour investigation of DLL elucidated the regressed proliferation of ascitic and solid tumour cells, which was paralleled with blockade of tumour neovasculature. DLL-treated mice showed an up-regulated immunoregulatory cytokine IL-2 in contrast to severely declined levels in control mice. Mechanistic validation revealed that DLL has abrogated the microvessel formation by weakening the proangiogenic signals, specifically nuclear factor kappa B (NF-κB), hypoxia inducible factor 1α (HIF-1 α), matrix metalloproteinase (MMP)-2 and 9 and vascular endothelial growth factor (VEGF) in malignant cells leading to tumour regression. In summary, it is evident that the dietary lectin DLL potentially dampens the malignant establishment by mitigating neoangiogenesis and immune shutdown. For the first time, to our knowledge, this study illustrates the critical role of DLL as an immunostimulatory and anti-angiogenic molecule in cancer therapeutics.