Bakuchiol suppresses proliferation of skin cancer cells by directly targeting Hck, Blk, and p38 MAP kinase

Recent advances in hematopoietic cell kinase in cancer progression: Mechanisms and inhibitors

Hematopoietic cell kinase (Hck), a non-receptor tyrosine kinase belonging to the Src kinase family, is intricately linked to the pathogenesis of numerous human diseases, with a particularly pronounced association with cancer. Hck not only directly impacts the proliferation, migration, and apoptosis of cancer cells but also interacts with JAK/STAT, MEK/ERK, PI3K/AKT, CXCL12/CXCR4, and other pathways. Hck also influences the tumor microenvironment to facilitate the onset and progression of cancer. This paper delves into the functional role and regulatory mechanisms of Hck in various solid tumors. Additionally, it explores the implications of Hck in hematological malignancies. The review culminates with a summary of the current research status of Hck inhibitors, the majority of which are in the pre-clinical phase of investigation. Notably, these inhibitors are predominantly utilized in the therapeutic management of leukemia, with their combinatorial potential indicating promising avenues for future research. In conclusion, this review underscores the significance of the mechanism of Hck in solid tumors. This insight is crucial for comprehending the current research trends regarding Hck: targeted therapy against Hck shows great promise in both diagnosis and treatment of malignant tumors. Further investigation into the role of Hck in cancer, coupled with the development of specific inhibitors, has the potential to revolutionize approaches to cancer treatment.

Anti-Allergic and Anti-inflammatory Effects of Bakuchiol on Ovalbumin-Induced Allergic Rhinitis in Mice

Allergic rhinitis (AR) is a prevalent inflammatory disease primarily affecting the nasal mucosa and is caused by allergies. The common symptoms of AR include rhinorrhea, sneezing, itchy nose, congestion, teary eyes, and nasal rubbings. The present study assessed the beneficial properties of bakuchiol on OVA-induced AR in mice via the regulation of inflammatory responses. AR was induced by injecting (i.p.) OVA (50 µg) and aluminum hydroxide (1 mg) into mice at various time intervals. The bakuchiol treatment was done at dosages of 10 and 20 mg/kg with dexamethasone (2.5 mg/kg) as a positive control. The body weight and nasal symptoms were measured on the day of the last OVA challenge. For in vitro tests, mouse splenocytes were isolated, sensitized with 20 µL OVA, and then treated with 10 µM bakuchiol. The levels of pro-inflammatory cytokines, immunoglobulins, histamine, leukotriene C4 (LTC-4), and prostaglandin D2 (PGD2) were assayed using the corresponding assay kits. The assay kits were also used to analyze the status of oxidative stress markers. The Th1/Th2 cell proportion was assessed using flow cytometry. The bakuchiol (10 and 20 mg/kg) treatment reduced the nasal symptoms in AR mice. Bakuchiol decreased the levels of IL-4, IL-5, IL-13, Igs (IgE and IgG1), histamine, IL-10, IL-33, and TNF-α in AR mice. Bakuchiol also reduced PGDA and LTC-4 levels in the NLF of AR mice. The ROS and MDA levels were decreased, whereas boosted SOD activity was observed in the bakuchiol-treated AR mice. The eosinophil count was decreased in the nasal tissues of bakuchiol-treated AR mice. Bakuchiol also influenced the Th1 and Th2 cell proportions in AR mice. The present findings suggest that bakuchiol is effective against OVA-mediated allergic and inflammatory responses in AR mice through its strong anti-inflammatory properties.

Ferroptosis-Regulated Natural Products and miRNAs and Their Potential Targeting to Ferroptosis and Exosome Biogenesis

Ferroptosis, which comprises iron-dependent cell death, is crucial in cancer and non-cancer treatments. Exosomes, the extracellular vesicles, may deliver biomolecules to regulate disease progression. The interplay between ferroptosis and exosomes may modulate cancer development but is rarely investigated in natural product treatments and their modulating miRNAs. This review focuses on the ferroptosis-modulating effects of natural products and miRNAs concerning their participation in ferroptosis and exosome biogenesis (secretion and assembly)-related targets in cancer and non-cancer cells. Natural products and miRNAs with ferroptosis-modulating effects were retrieved and organized. Next, a literature search established the connection of a panel of ferroptosis-modulating genes to these ferroptosis-associated natural products. Moreover, ferroptosis-associated miRNAs were inputted into the miRNA database (miRDB) to bioinformatically search the potential targets for the modulation of ferroptosis and exosome biogenesis. Finally, the literature search provided a connection between ferroptosis-modulating miRNAs and natural products. Consequently, the connections from ferroptosis-miRNA-exosome biogenesis to natural product-based anticancer treatments are well-organized. This review sheds light on the research directions for integrating miRNAs and exosome biogenesis into the ferroptosis-modulating therapeutic effects of natural products on cancer and non-cancer diseases.

Bakuchiol targets mitochondrial proteins, prohibitins and voltage-dependent anion channels: New insights into developing antiviral agents

We previously reported that bakuchiol, a phenolic isoprenoid anticancer compound, and its analogs exert anti-influenza activity. However, the proteins targeted by bakuchiol remain unclear. Here, we investigated the chemical structures responsible for the anti-influenza activity of bakuchiol and found that all functional groups and C6 chirality of bakuchiol were required for its anti-influenza activity. Based on these results, we synthesized a molecular probe containing a biotin tag bound to the C1 position of bakuchiol. With this probe, we performed a pulldown assay for Madin-Darby canine kidney cell lysates and purified the specific bakuchiol-binding proteins with SDS-PAGE. Using nanoLC-MS/MS analysis, we identified prohibitin (PHB) 2, voltage-dependent anion channel (VDAC) 1, and VDAC2 as binding proteins of bakuchiol. We confirmed the binding of bakuchiol to PHB1, PHB2, and VDAC2 in vitro using Western blot analysis. Immunofluorescence analysis showed that bakuchiol was bound to PHBs and VDAC2 in cells and colocalized in the mitochondria. The knockdown of PHBs or VDAC2 by transfection with specific siRNAs, along with bakuchiol cotreatment, led to significantly reduced influenza nucleoprotein expression levels and viral titers in the conditioned medium of virus-infected Madin-Darby canine kidney cells, compared to the levels observed with transfection or treatment alone. These findings indicate that reducing PHBs or VDAC2 protein, combined with bakuchiol treatment, additively suppressed the growth of influenza virus. Our findings indicate that bakuchiol exerts anti-influenza activity via a novel mechanism involving these mitochondrial proteins, providing new insight for developing anti-influenza agents.

Role of Phytoconstituents in Cancer Treatment: A Review

Over the years, natural compounds have become a significant advancement in cancer treatment, primarily due to their effectiveness, safety, bio-functionality, and wide range of molecular structures. They are now increasingly preferred in drug discovery due to these attributes. These compounds, whether occurring naturally or with synthetic modifications, find applications in various fields like biology, medicine, and engineering. While chemotherapy has been a successful method for treating cancer, it comes with systemic toxicity. To address this issue, researchers and medical practitioners are exploring the concept of combinational chemotherapy. This approach aims to reduce toxicity by using a mix of natural substances and their derivatives in clinical trials and prescription medications. Among the most extensively studied natural anticancer compounds are quercetin, curcumin, vincristine, and vinblastine. These compounds play crucial roles as immunotherapeutics and chemosensitizers, both as standalone treatments and in combination therapies with specific mechanisms. This review article provides a concise overview of the functions, potentials, and combinations of natural anticancer compounds in cancer treatment, along with their mechanisms of action and clinical applications.

Discovery of 2,5-diaminopyrimidine derivatives as the first series of selective monomeric degraders of B-lymphoid tyrosine kinase

B-lymphoid tyrosine kinase (BLK) is an important knot of B cell receptor signaling, and regulates the function and development of B cells subset. Dysfunction of BLK is correlated with autoimmune diseases and cancer. There is an urgent need to develop selective BLK modulators to facilitate the studies of BLK in biological processes. Herein, we report the discovery of a series of 2,5-diaminopyrimidine-based compounds capable of selectively degrading BLK. The optimized compounds 9-11 possess weak biochemical inhibitory activities against BLK, yet they effectively degrade BLK and show high selectivity for BLK over other structurally and functionally related SRC family and TEC family kinases. Furthermore, compounds 9 and 11 demonstrate potent inhibitory activities in several B-lymphoid cell lines. As the first series of effective and selective monomeric BLK degraders, compounds 9-11 serve as valuable tools for further investigation of the functions of BLK.

Exploiting bioactive natural products of marine origin: Evaluation of the meroterpenoid metachromin V as a novel potential therapeutic drug for colorectal cancer

Colorectal cancer (CRC) is the second most common cause of cancer death, leading to almost 1 million deaths per year. Despite constant progress in surgical and therapeutic protocols, the 5-year survival rate of advanced CRC patients remains extremely poor. Colorectal Cancer Stem Cells (CRC-CSCs) are endowed with unique stemness-related properties responsible for resistance, relapse and metastasis. The development of novel therapeutics able to tackle CSCs while avoiding undesired toxicity is a major need for cancer treatment. Natural products are a large reservoir of unexplored compounds with possible anticancer bioactivity, sustainability, and safety. The family of meroterpenoids derived from sponges share interesting bioactive properties. Bioassay-guided fractionation of a meroterpenoids extract led to the isolation of three compounds, all cytotoxic against several cancer cell lines: Metachromins U, V and W. In this study, we evaluated the anticancer potential of the most active one, Metachromins V (MV), on patient-derived CRC-CSCs. MV strongly impairs CSCs-viability regardless their mutational background and the cytotoxic effect is maintained on therapy-resistant metastatic CSCs. MV affects cell cycle progression, inducing a block in G2 phase in all the cell lines tested and more pronouncedly in CRC-CSCs. Moreover, MV triggers an important reorganization of the cytoskeleton and a strong reduction of Rho GTPases expression, impairing CRC-CSCs motility and invasion ability. By Proteomic analysis identified a potential molecular target of MV: CCAR1, that regulates apoptosis under chemotherapy treatments and affect β-catenin pathway. Further studies will be needed to confirm and validate these data in in vivo experimental models.

Loss of BLK expression as a potential predictor of poor prognosis and immune checkpoint blockade response in NSCLC and contribute to tumor progression

BACKGROUND

Immune checkpoint blockade (ICB) has been proved to have significant anti-tumor effect in the clinical treatment of non-small cell lung cancer (NSCLC). Therefore, biomarkers predicting ICB response can provide better treatment for patients with NSCLC.

METHODS

Differential expression genes (DEGs) were identified by ImmuCellAI database. Copy number alteration (CNA) was analyzed by cBioPortal. The predicted efficiency of 4 genes on cancer immunotherapy was assessed by ROC analysis. The survival value of BLK was analyzed by Kaplan-Meier plotter and Prognoscan analysis. Clinical significance of BLK IHC-TMA score in NSCLC was also explored. The CCK-8 assay, wound healing assay, western blot assay in vitro and subcutaneous xenograft experiments in vivo were used for investigating the functions of BLK. The RNA-sequencing were performed to screen BLK regulated genes and conducted for GO/KEGG enrichment analysis. The transcriptional regulatory factor of BLK promoter region was predicted by ChIP-seq analysis.

RESULTS

39 common DEGs between ICB Response (R) group and No Response (NR) group with NSCLC were identified, in which the CNA frequency of BLK deletion (> 6%) was found. The predicted efficiency of BLK on immunotherapy was performed best in NSCLC (AUC>0.7). Low expression of BLK was related to NSCLC with significantly poor prognosis. BLK overexpression can inhibit growth of NSCLC via activating apoptosis pathway, inhibiting the G2M checkpoint and Glycolysis pathway. The enrichment analysis indicated that BLK regulated genes related to oncogenic potential in NSCLC. Besides, BLK expression was inhibited via H3K27me3 modification in A549 and H1299 cells. BLK mRNA level was negatively correlated with methylation and positively correlated with the tumor purity in NSCLC.

CONCLUSION

Our study provides strong evidence that low expression of BLK may serve as a biomarker for poor prognosis in NSCLC, while response to ICB therapy and contributes to NSCLC tumor progression.

Effects of traditional artiri La Li formulation on experimental models of vitiligo and mechanisms of melanogenesis

ETHNOPHARMACOLOGICAL RELEVANCE

Artiri La Li Honey Pill (ALLHP) is a traditional medicinal formula that is widely used in Xinjiang, China, for the treatment of vitiligo. Since the cause of vitiligo has not been determined, no satisfactory treatment is available. Clinical interventions include pharmacological treatment with psoralen, usually in conjunction with ultraviolet A (UVA) radiation, but toxic side effects limit this application. Studies on the activity and mechanisms of ALLHP are scarce.

AIM OF THE STUDY

To verify the therapeutic effect of ALLHP on vitiligo and determine its effectiveness as a theoretical and experimental basis for the development of innovative drugs with independent intellectual property rights and the effective use of local resources.

MATERIALS AND METHODS

The experimental animal model of vitiligo was established by chemical decoloring. Rats were treated with gradient doses of ALLHP. The therapeutic effect was judged by gross observation. The contents of TYR, MAO, AchE and MDA in serum and skin tissue, the number of hair follicles containing melanin in skin tissue, the distribution of epidermal melanin, and the weight index of immune organs were detected, and the therapeutic effect of ALLHP on vitiligo was evaluated. In addition, certain monomer components in ALLHP were used to intervene in the zebrafish juvenile melanin suppression model, and the melanin-activating activities of some monomer components in ALLHP were screened by counting the melanin area ratio.

RESULTS

ALLHP increased the number of melanin-containing hair follicles and the epidermal melanin content in the skin of experimental vitiligo animals, repaired the skin cell morphology to a certain extent, increased the content of TYR in serum and skin, and reduced the content of MDA, AchE and MAO. Carvone, Luteolin, Psoralen and Psoraleae phenol and Bakuchiol could increase the melanin area of experimental melanin inhibition in zebrafish.

CONCLUSION

According to the results of this study, ALLHP can increase the number of melanin-containing hair follicles and the epidermal melanin content in the skin of vitiligo animals and restore skin cell morphology to a certain extent by reducing oxidative stress in epidermal tissue. A wide range of active ingredients may promote melanogenesis with ALLHP.

Applications of bakuchiol in dermatology: Systematic review of the literature

BACKGROUND

Bakuchiol (BAK), a meroterpene phenol abundant in the plant Psoralea corylifolia, is an emerging cosmeceutical agent with promising anti-aging, anti-inflammatory, and antibacterial properties. The trend for "clean" skincare products and search for anti-aging retinoid alternatives have poised BAK as a "must-have" ingredient in skincare.

AIMS

Our aim was to review the data for the applications of BAK in dermatology.

METHODS

This is a systematic review of PubMed.

RESULTS

Thirty articles matched our search terms ["Bakuchiol" and "Dermatology"] or ["Bakuchiol" and "Skin"] of which one did not meet inclusion criteria, 16 were pre-clinical studies, seven clinical studies, three commentaries, two narrative reviews, and one report on adverse events. BAK has been mostly studied for its effects on photoaging, acne, and post-inflammatory hyperpigmentation (PIH), showing beneficial results comparable to those achieved by topical retinoids. While having no structural resemblance to retinoids, BAK can function as a retinol analog, through retinol-like regulation of gene expression. In in vivo studies, BAK was used alone or in combination with other products resulting in a significant reduction in photodamage, hyperpigmentation, wrinkle scores, and acne severity. Additionally, in vitro studies hinted at its anti-cancer properties by inhibiting epidermal growth factor induced neoplastic cell transformation. Also, demonstrated potential applications in psoriasis by normalizing keratinocyte activity and in pigmentary disorders through inhibition of melanogenesis. There was one adverse event case reported of contact dermatitis in the literature.

CONCLUSIONS

Bakuchiol is a retinol alternative with anti-aging, antibacterial, and anti-inflammatory properties. Additional studies are warranted to better understand its applications in dermatology.

Natural Products as Anticancer Agents: Current Status and Future Perspectives

Natural products have been an invaluable and useful source of anticancer agents over the years. Several compounds have been synthesized from natural products by modifying their structures or by using naturally occurring compounds as building blocks in the synthesis of these compounds for various purposes in different fields, such as biology, medicine, and engineering. Multiple modern and costly treatments have been applied to combat cancer and limit its lethality, but the results are not significantly refreshing. Natural products, which are a significant source of new therapeutic drugs, are currently being investigated as potential cytotoxic agents and have shown a positive trend in preclinical research and have prompted numerous innovative strategies in order to combat cancer and expedite the clinical research. Natural products are becoming increasingly important for drug discovery due to their high molecular diversity and novel biofunctionality. Furthermore, natural products can provide superior efficacy and safety due to their unique molecular properties. The objective of the current review is to provide an overview of the emergence of natural products for the treatment and prevention of cancer, such as chemosensitizers, immunotherapeutics, combinatorial therapies with other anticancer drugs, novel formulations of natural products, and the molecular mechanisms underlying their anticancer properties.

Multidirectional activity of bakuchiol against cellular mechanisms of facial aging - Experimental evidence for a holistic treatment approach

Objective

Skin ageing is a multifactorial process involving formation of reactive oxygen species, consecutive inflammation with reduced epidermal and dermal cell viability and resulting damage to the extracellular matrix. Effective dermocosmetic treatment modalities should ideally address these hallmarks in a holistic approach. Here, we determined the corresponding activity profile of bakuchiol, a plant‐derived meroterpene, in an array of in vitro, ex vivo and in vivo studies and compared it to retinol, currently considered as gold standard in topical antiageing cosmetics.

Methods

The antioxidative capacity and power of bakuchiol and retinol were analysed by measuring 2,2′‐diphenyl‐1‐picrylhydrazyl (DPPH) reduction via its absorption decay and electron spin resonance spectroscopy, respectively. Effects on prostaglandin E2 (PGE2), macrophage migration inhibitory factor (MIF), fibroblast growth factor 7 (FGF7), collagen type I and VII (COL1A1, COL7A1), fibronectin (FN) levels as well as the metabolization of water‐soluble tetrazolium 1 (WST‐1) were determined in human dermal fibroblasts. Epidermal regeneration was assessed utilizing an in vitro wound healing model. FN protein levels were analysed ex vivo after treatment with a formulation containing bakuchiol, retinol or vehicle using suction blister fluid. Skin condition improvement was determined in vivo in a split‐face comparison study after application of bakuchiol or vehicle.

Results

In contrast to retinol, bakuchiol demonstrated high antioxidative efficacy. Levels of PGE2 and MIF were significantly decreased by both bakuchiol and retinol. Bakuchiol but not retinol significantly increased FGF7 protein levels. WST‐1 metabolization levels were significantly augmented by bakuchiol and retinol. Bakuchiol and retinol application led to a significant augmentation of COL1A1, COL7A1 and FN protein levels. Wounds supplemented with bakuchiol but not retinol displayed a significant increase in epidermis regeneration. Clinically, areas treated with a bakuchiol‐containing formulation showed a statistically significant increase in FN protein values after a 4‐week application compared to untreated areas and areas treated with vehicle.

Conclusion

These data provide evidence for the multidirectional efficacy of bakuchiol against cellular hallmarks of skin ageing. Its activity profile shares some common features with retinol but demonstrates several hitherto unknown biopositive effects in our studies, namely stimulation of the critical extracellular matrix component FN, and accelerated epidermal regeneration and wound healing.

Bakuchiol – a natural meroterpenoid: structure, isolation, synthesis and functionalization approaches

Bakuchiol is an emblematic meroterpene class of natural product extracted from Psoralea corylifolia. It has been reported to possess a broad range of biological and pharmacological properties and is considered as a leading biomolecule. It is highly desirable to devise an efficient approach to access bakuchiol and its chemical biology applications. In this review we provided structural features, isolation methods, various chemical routes and late-stage functionalization (LSF) approaches for bakuchiol and its derivatives. Moreover, this review encompasses the structure–activity relationships (SAR), value-added contributions and future perspectives of bakuchiol

The isolation methods, various chemical routes and late-stage functionalization approaches and structure–activity relationships of bakuchiol – a meroterpene class of natural product has been discussed in detail.

Organic synthesis and anti-influenza A virus activity of cyclobakuchiols A, B, C, and D

Novel antiviral agents for influenza, which poses a substantial threat to humans, are required. Cyclobakuchiols A and B have been isolated from Psoralea glandulosa, and cyclobakuchiol C has been isolated from P. corylifolia. The structural differences between cyclobakuchiol A and C arise due to the oxidation state of isopropyl group, and these compounds can be derived from (+)-(S)-bakuchiol, a phenolic isoprenoid compound present in P. corylifolia seeds. We previously reported that bakuchiol induces enantiospecific anti-influenza A virus activity involving nuclear factor erythroid 2-related factor 2 (Nrf2) activation. However, it remains unclear whether cyclobakuchiols A–C induce anti-influenza A virus activity. In this study, cyclobakuchiols A, B, and C along with cyclobakuchiol D, a new artificial compound derived from cyclobakuchiol B, were synthesized and examined for their anti-influenza A virus activities using Madin-Darby canine kidney cells. As a result, cyclobakuchiols A–D were found to inhibit influenza A viral infection, growth, and the reduction of expression of viral mRNAs and proteins in influenza A virus-infected cells. Additionally, these compounds markedly reduced the mRNA expression of the host cell influenza A virus-induced immune response genes, interferon-β and myxovirus-resistant protein 1. In addition, cyclobakuchiols A–D upregulated the mRNA levels of NAD(P)H quinone oxidoreductase 1, an Nrf2-induced gene, in influenza A virus-infected cells. Notably, cyclobakuchiols A, B, and C, but not D, induced the Nrf2 activation pathway. These findings demonstrate that cyclobakuchiols have anti-influenza viral activity involving host cell oxidative stress response. In addition, our results suggest that the suitably spatial configuration between oxidized isopropyl group and phenol moiety in the structure of cyclobakuchiols is required for their effect.

Emerging Kinase Therapeutic Targets in Pancreatic Ductal Adenocarcinoma and Pancreatic Cancer Desmoplasia

Kinase drug discovery represents an active area of therapeutic research, with previous pharmaceutical success improving patient outcomes across a wide variety of human diseases. In pancreatic ductal adenocarcinoma (PDAC), innovative pharmaceutical strategies such as kinase targeting have been unable to appreciably increase patient survival. This may be due, in part, to unchecked desmoplastic reactions to pancreatic tumors. Desmoplastic stroma enhances tumor development and progression while simultaneously restricting drug delivery to the tumor cells it protects. Emerging evidence indicates that many of the pathologic fibrotic processes directly or indirectly supporting desmoplasia may be driven by targetable protein tyrosine kinases such as Fyn-related kinase (FRK); B lymphoid kinase (BLK); hemopoietic cell kinase (HCK); ABL proto-oncogene 2 kinase (ABL2); discoidin domain receptor 1 kinase (DDR1); Lck/Yes-related novel kinase (LYN); ephrin receptor A8 kinase (EPHA8); FYN proto-oncogene kinase (FYN); lymphocyte cell-specific kinase (LCK); tec protein kinase (TEC). Herein, we review literature related to these kinases and posit signaling networks, mechanisms, and biochemical relationships by which this group may contribute to PDAC tumor growth and desmoplasia.

Src Family Protein Kinase Controls the Fate of B Cells in Autoimmune Diseases

There are more than 80 kinds of autoimmune diseases known at present, including rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), systemic sclerosis (SSc), inflammatory bowel disease (IBD), as well as other disorders. Autoimmune diseases have a characteristic of immune responses directly attacking own tissues, leading to systematic inflammation and subsequent tissue damage. B cells play a vital role in the development of autoimmune diseases and differentiate into plasma cells or memory B cells to secrete high-affinity antibody or provide long-lasting function. Drugs targeting B cells show good therapeutic effects for the treatment of autoimmune diseases, such as rituximab (anti-CD20 antibody). Src family protein kinases (SFKs) are believed to play important roles in a variety of cellular functions such as growth, proliferation, and differentiation of B cell via B cell antigen receptor (BCR). Lck/Yes-related novel protein tyrosine kinase (LYN), BLK (B lymphocyte kinase), and Fyn are three different kinds of SFKs mainly expressed in B cells. LYN has a dual role in the BCR signal. On the one hand, positive signals are beneficial to the development and maturation of B cells. On the other hand, LYN can also inhibit excessively activated B cells. BLK is involved in the proliferation, differentiation, and immune tolerance of B lymphocytes, and further affects the function of B cells, which may lead to autoreactive or regulatory cellular responses, increasing the risk of autoimmune diseases. Fyn may affect the development of autoimmune disorders via the differentiation of B cells in the early stage of B cell development. This article reviews the recent advances of SFKs in B lymphocytes in autoimmune diseases.

RCC2 Promotes Esophageal Cancer Growth by Regulating Activity and Expression of the Sox2 Transcription Factor

Regulator of chromosome condensation 2 (RCC2) is a protein located in the centrosome, which ensures that cell division proceeds properly. Previous reports show that RCC2 is overexpressed in some cancers and could play a key role in tumor development, but the mechanisms concerning how this occurs are not understood. Furthermore, no evidence exists regarding its role in esophageal cancer. We studied the relevance of RCC2 in esophageal cancer growth and its regulation on Sox2, an important transcription factor promoting esophageal cancer. RCC2 was overexpressed in esophageal tumors compared with normal tissue, and this overexpression was associated with tumorigenicity by increasing cell proliferation, anchorage-independent growth, and migration. These oncogenic effects were accompanied by overexpression of Sox2. RCC2 upregulated and stabilized Sox2 expression and its target genes by inhibiting ubiquitination-mediated proteasome degradation. Likewise, RCC2 increased the transcriptional activity and promoter binding of Sox2. In vivo studies indicated that RCC2 and Sox2 were overexpressed in esophageal tumors compared with normal tissue, and this upregulation occurs in the esophageal basal cell layer for both proteins. In conditional knockout mice, RCC2 deletion decreased the tumor nodule formation and progression in the esophagus compared with wild-type mice. Proliferating cell nuclear antigen expression, a cell proliferation marker, was also downregulated in RCC2 knockout mice. Overall, our data show for the first time that RCC2 is an important protein for the stabilization and transcriptional activation of Sox2 and further promotion of malignancy in esophageal cancer. IMPLICATIONS: This study shows that RCC2 controls Sox2 expression and transcriptional activity to mediate esophageal cancer formation.

Evaluating antitumor activity of antiglypican-3 therapy in experimentally induced skin cancer in mice

Glypican-3 (GPC3) is considered as a cell surface heparan sulfate proteoglycan. It is overexpressed in skin cancer and promotes tumor progression and pathogenicity. Therefore, we aimed to find out the therapeutic effects of immuno-suppressing GPC3 in skin cancer experimentally induced in mice as well as to underline molecular mechanisms especially inflammatory and apoptotic pathways. Skin cancer was experimentally induced in mice by repeated rubbing of mice skin with 7,12-dimethylbenz (a) anthracene. Mice were injected with anti-GPC3. Skin samples were isolated to investigate the gene and protein expression of GPC3, Wnt-1, NFκB, TNF-α, IGF-1, p38 MAPK and caspase-3 using PCR, Western blot and ELISA. Moreover, skin sections were stained with hematoxylin and eosin. Treating skin cancer mice with anti-GPC3 significantly blocked GPC3, which is accompanied by amelioration of skin cancer-induced increase in the numbers of tumors and scratching behavior. Moreover, anti-GPC3 attenuated skin cancer-induced increase in the expression of Wnt-1, NFκB, TNF-α, IGF-1, p38 MAPK and caspase-3. In parallel, anti-GPC3 reduced degeneration of melanocyte cells and reduced phagocytic cells epidermal hyperplasia and dysplasia in skin sections stained with hematoxylin and eosin stain. In conclusion, anti-GPC3 produced anti-tumor effects against skin cancer, which can be explained by reduction in both inflammatory and apoptotic pathways. Targeting GPC3 is a promising therapeutic approach for skin cancer.

Src Family Kinases as Therapeutic Targets in Advanced Solid Tumors: What We Have Learned so Far

Src is the prototypal member of Src Family tyrosine Kinases (SFKs), a large non-receptor kinase class that controls multiple signaling pathways in animal cells. SFKs activation is necessary for the mitogenic signal from many growth factors, but also for the acquisition of migratory and invasive phenotype. Indeed, oncogenic activation of SFKs has been demonstrated to play an important role in solid cancers; promoting tumor growth and formation of distant metastases. Several drugs targeting SFKs have been developed and tested in preclinical models and many of them have successfully reached clinical use in hematologic cancers. Although in solid tumors SFKs inhibitors have consistently confirmed their ability in blocking cancer cell progression in several experimental models; their utilization in clinical trials has unveiled unexpected complications against an effective utilization in patients. In this review, we summarize basic molecular mechanisms involving SFKs in cancer spreading and metastasization; and discuss preclinical and clinical data highlighting the main challenges for their future application as therapeutic targets in solid cancer progression

Bakuchiol protects against pathological cardiac hypertrophy by blocking NF-κB signaling pathway

Bakuchiol (Bak), a monoterpene phenol isolated from the seeds of Psoralea corylifolia, has been widely used to treat a large variety of diseases in both Indian and Chinese folkloric medicine. However, the effects of Bak on cardiac hypertrophy remain unclear. Therefore, the present study was designed to determine whether Bak could alleviate cardiac hypertrophy. Mice were subjected to aortic banding (AB) to induce cardiac hypertrophy model. Bak of 1 ml/100 g body weight was given by oral gavage once a day from 1 to 8 weeks after surgery. Our data demonstrated for the first time that Bak could attenuate pressure overload-induced cardiac hypertrophy and could attenuate fibrosis and the inflammatory response induced by AB. The results further revealed that the effect of Bak on cardiac hypertrophy was mediated by blocking the activation of the NF-κB signaling pathway. In vitro studies performed in neonatal rat cardiomyocytes further proved that the protective effect of Bak on cardiac hypertrophy is largely dependent on the NF-κB pathway. Based on our results, Bak shows profound potential for its application in the treatment of pathological cardiac hypertrophy, and we believe that Bak may be a promising therapeutic candidate to treat cardiac hypertrophy and heart failure.

The active compounds derived from Psoralea corylifolia for photochemotherapy against psoriasis-like lesions: The relationship between structure and percutaneous absorption

8‑Methoxypsoralen (8-MOP) in combination with ultraviolet A (PUVA) is a photochemotherapy for management of psoriasis. 8-MOP is a natural compound from Psoralea corylifolia. The present work was undertaken to evaluate the percutaneous absorption of five compounds derived from P. corylifolia, and to further explore the inhibitory effect on psoriasis-like lesions generated by imiquimod stimulation in a mouse model. 8-MOP, psoralen, isopsoralen, psoralidin, and bakuchiol were comparatively tested for in vitro skin permeation, keratinocyte apoptosis, and in vivo antipsoriatic potency. The pig ear skin deposition of 8-MOP, isopsoralen, and bakuchiol at an equimolar dose was 0.47, 0.58, and 0.50 nmol/mg, respectively, which was comparable and higher than that of psoralen (0.25 nmol/mg) and psoralidin (0.14 nmol/mg). Psoralidin and bakuchiol were absorbed into the skin without further penetration across the skin. Besides experimental data of physicochemical properties, the hydrogen bond number, total polarity surface, and stratum corneum lipid docking calculated could explain the correlation of the penetrant structure with the skin permeability. The antiproliferative activity against keratinocytes was stronger for 8-MOP and isopsoralen than the others. Topical application of PUVA by using 8-MOP and isopsoralen on imiquimod-induced plaque significantly reduced transepidermal water loss from 55 to 33 and 38 g/m²/h, respectively. The epidermal thickening elicited by imiquimod (117 μm) was decreased to 62 and 26 μm by 8-MOP and isopsoralen application. IL-6 expression in psoriasiform skin was downregulated by isopsoralen but not 8-MOP. Isopsoralen may be a potential candidate for PUVA therapy.

Targeting PRPK and TOPK for skin cancer prevention and therapy

Solar ultraviolet (sUV) irradiation is a major environmental carcinogen that can cause inflammation and skin cancer. The costs and morbidity associated with skin cancer are increasing, and therefore identifying molecules that can help prevent skin carcinogenesis is important. In this study, we identified the p53-related protein kinase (PRPK) as a novel oncogenic protein that is phosphorylated by the T-LAK cell-originated protein kinase (TOPK). Knockdown of TOPK inhibited PRPK phosphorylation and conferred resistance to solar-simulated light (SSL)-induced skin carcinogenesis in mouse models. In the clinic, acute SSL irradiation significantly increased epidermal thickness as well as total protein and phosphorylation levels of TOPK and PRPK in human skin tissues. We identified two PRPK inhibitors, FDA-approved rocuronium bromide (Zemuron^®) or betamethasone 17-valerate (Betaderm^®) that could attenuate TOPK-dependent PRPK signaling. Importantly, topical application of either rocuronium bromide or betamethasone decreased SSL-induced epidermal hyperplasia, neovascularization, and cutaneous squamous cell carcinoma (cSCC) development in SKH1 (Crl: SKH1-Hr^hr) hairless mice by inhibiting PRPK activation, and also reduced expression of the proliferation and oncogenesis markers, COX-2, cyclin D1, and MMP-9. This study is the first to demonstrate that targeting PRPK could be useful against sUV-induced cSCC development.

Identification and analysis of mutational hotspots in oncogenes and tumour suppressors

Background

The key to interpreting the contribution of a disease-associated mutation in the development and progression of cancer is an understanding of the consequences of that mutation both on the function of the affected protein and on the pathways in which that protein is involved. Protein domains encapsulate function and position-specific domain based analysis of mutations have been shown to help elucidate their phenotypes.

Results

In this paper we examine the domain biases in oncogenes and tumour suppressors, and find that their domain compositions substantially differ. Using data from over 30 different cancers from whole-exome sequencing cancer genomic projects we mapped over one million mutations to their respective Pfam domains to identify which domains are enriched in any of three different classes of mutation; missense, indels or truncations. Next, we identified the mutational hotspots within domain families by mapping small mutations to equivalent positions in multiple sequence alignments of protein domains We find that gain of function mutations from oncogenes and loss of function mutations from tumour suppressors are normally found in different domain families and when observed in the same domain families, hotspot mutations are located at different positions within the multiple sequence alignment of the domain.

Conclusions

By considering hotspots in tumour suppressors and oncogenes independently, we find that there are different specific positions within domain families that are particularly suited to accommodate either a loss or a gain of function mutation. The position is also dependent on the class of mutation. We find rare mutations co-located with well-known functional mutation hotspots, in members of homologous domain superfamilies, and we detect novel mutation hotspots in domain families previously unconnected with cancer. The results of this analysis can be accessed through the MOKCa database (http://strubiol.icr.ac.uk/extra/MOKCa).

Characterization of human UDP-glucuronosyltransferases responsible for glucuronidation and inhibition of norbakuchinic acid, a primary metabolite of hepatotoxicity and nephrotoxicity component bakuchiol inPsoralea corylifolia L

Norbakuchinic acid (NBKA) is the most abundant metabolite of bakuchiol (a hepatotoxicity and nephrotoxicity component inPsoralea corylifoliaL.) in plasma and urine.

Quantitative Analysis of Psoralea corylifolia Linne and its Neuroprotective and Anti-Neuroinflammatory Effects in HT22 Hippocampal Cells and BV-2 Microglia

The seeds of Psoralea corylifolia L. (P. corylifolia), also known as “Bo-Gol-Zhee” in Korea, are used in a traditional herbal medicine for treating various skin diseases. In the present study, we performed quantitative analyses of the seven standard components of P. corylifolia: psoralen, angelicin, neobavaisoflavone, psoralidin, isobavachalcone, bavachinin, and bakuchiol, using high-performance liquid chromatography. We also investigated the neuroprotective and anti-neuroinflammation effects of P. corylifolia and its standard components in the hippocampal cell line HT22 and microglia cell line BV-2. A 70% ethanol extract of P. corylifolia was prepared and the seven standard components were separated using C-18 analytical columns by gradient solvents with acetonitrile and water, and ultraviolet detection at 215, 225 and 275 nm. The analytical method showed high linearity, with a correlation coefficient of ≥0.9999. The amounts of the standard components ranged from 0.74 to 11.71 mg/g. Among the components, bakuchiol (11.71 mg/g) was the most potent phytochemical component of P. corylifolia. Furthermore, we analyzed the inhibitory effects of the components from P. corylifolia to determine the bioactive compound needed to regulate neuronal cell changes. Angelicin, isobavachalcone, and bakuchiol suppressed lipopolysaccharide (LPS)-stimulated nitric oxide production in LPS-treated BV-2 microglia more significantly than did the other components. In HT22 hippocampal cells, neobavaisoflavone and bakuchiol had more potent inhibitory activity against hydrogen peroxide-induced cell death. Taken together of the quantification and efficacy analyses, bakuchiol appeared to be the most potent bioactive phytochemical component of P. corylifolia for the potential treatment of neurodegenerative diseases.

Identification of UDP-glucuronosyltransferases 1A1, 1A3 and 2B15 as the main contributors to glucuronidation of bakuchiol, a natural biologically active compound

1. Bakuchiol, one of the main active compounds of Psoralea corylifolia, possesses a variety of pharmacological activities such as anti-tumor and anti-aging effects. Here, we aimed to characterize the glucuronidation of bakuchiol using human liver microsomes (HLM) and expressed UDP-glucuronosyltransferase (UGT) enzymes. 2. The glucuronide of bakuchiol was confirmed by liquid chromatography-mass spectrometry (LC-MS) and β-glucuronidase hydrolysis assay. Glucuronidation rates and kinetic parameters were derived by enzymatic incubation and model fitting. Activity correlation analyses were performed to identify the main UGT isoforms contributing to hepatic metabolism of bakuchiol. 3. Among the three UGT enzymes (i.e., UGT1A1, UGT1A3 and UGT2B15) capable of catalyzing bakuchiol glucuronidation, UGT2B15 showed the highest activity with a CL_int value of 100 μl/min/nmol. Bakuchiol glucuronidation was strongly correlated with glucuronidation of 5-hydroxyrofecoxib (r = 0.933; p < 0.001), 3-O-glucuronidation of β-estradiol (r = 0.719; p < 0.01) and significantly correlated with 24-O-glucuronidation of CDCA (r = 0.594; p < 0.05). In addition, a marked species difference existed in hepatic glucuronidation of bakuchiol. 4. In conclusion, UGT1A1, UGT1A3 and UGT2B15 were identified as the main contributors to glucuronidation of bakuchiol.