Capsaicin enhances the antitumor activity of sorafenib in hepatocellular carcinoma cells and mouse xenograft tumors through increased ERK signaling

Capsaicin enhances cisplatin-induced anti-metastasis of nasopharyngeal carcinoma by inhibiting EMT and ERK signaling via serpin family B member 2

Cisplatin (DDP)-based combined chemotherapy or concurrent chemoradiotherapy is the mainstay treatment for advanced-stage nasopharyngeal carcinoma (NPC), but needs improvement due to its severe side effects. Capsaicin (CAP) can enhance the anti-tumor activity of cytotoxic drugs. The aim of this study was to investigate the anti-metastasis activity of CAP in combination with DDP in NPC. Herein, CAP and DDP showed synergistic cytotoxic effects on NPC cells. CAP alone and DDP alone inhibited NPC migration and invasion in vitro and in vivo, and the combination of CAP and DDP had the greatest effect. Moreover, CAP upregulated the mRNA and protein expressions of serpin family B member 2 (SERPINB2). Further results showed that both SERPINB2 mRNA and protein expressions were downregulated in NPC cell lines and tissues and SERPINB2 overexpression inhibited NPC migration and invasion in vitro and in vivo, while silencing SERPINB2 acted oppositely. In addition, SERPINB2 was abnormally expressed in head and neck squamous cell carcinoma and other multiple cancers, and downregulation of SERPINB2 predicted poor prognosis in head and neck squamous cell carcinoma according to the Cancer Genome Atlas database. We further found that SERPINB2 overexpression inhibited epithelial-mesenchymal transition (EMT) and the phosphorylated extracellular signal-regulated kinase (p-ERK), and the inhibitory effect was enhanced by CAP and DDP. Altogether, our results suggest that the combined inhibition of CAP and DDP on NPC metastasis may be related to the inhibition of epithelial-mesenchymal transition and ERK signals mediated by SERPINB2, and CAP may help to improve the efficacy of DDP in the treatment of NPC and develop new therapeutic approaches.

Assessment of the therapeutic potential of a novel phosphoramidate acyclic nucleoside on induced hepatocellular carcinoma in rat model

AIMS

Hepatocellular Carcinoma (HCC) is renowned as a deadly primary cancer of hepatic origin. Sorafenib is the drug-of-choice for targeted treatment of unresectable end-stage HCC. Unfortunately, great proportion of HCC patients showed intolerance or unresponsiveness to treatment. This study assesses potency of novel ProTide; SH-PAN-19 against N-Nitrosodiethylamine (DEN)-induced HCC in male Wistar rats, compared to Sorafenib.

MAIN METHODS

Structural entity of the synthesized compound was substantiated via FT-IR, UV-Vis, 1H NMR and 13C NMR spectroscopic analysis. In vitro, SH-PAN-19 cytotoxicity was tested against 3 human cell lines; hepatocellular carcinoma; HepG-2, colorectal carcinoma; HCT-116 and normal fibroblasts; MRC-5. In vivo, therapeutic efficacy of SH-PAN-19 (300 mg/kg b.w./day) against HCC could be revealed and compared to that of Sorafenib (15 mg/kg b.w./day) by evaluating the morphometric, biochemical, histopathological, immunohistochemical and molecular key markers.

KEY FINDINGS

SH-PAN-19 was relatively safe toward MRC-5 cells (IC50 = 307.6 μg/mL), highly cytotoxic to HepG-2 cells (IC50 = 24.9 μg/mL) and prominently hepato-selective (TSI = 12.35). Oral LD50 of SH-PAN-19 was >3000 mg/kg b.w. DEN-injected rats suffered hepatomegaly, oxidative stress, elevated liver enzymes, hypoalbuminemia, bilirubinemia and skyrocketed AFP plasma titre. SH-PAN-19 alleviated the DEN-induced alterations in apoptotic, angiogenic and inflammatory markers. SH-PAN-19 produced a 2.5-folds increase in Caspase-9 and downregulated VEGFR-2, IL-6, TNF-α, TGFβ-1, MMP-9 and CcnD-1 to levels comparable to that elicited by Sorafenib. SH-PAN-19 resulted in near-complete pathological response versus partial response achieved by Sorafenib.

SIGNIFICANCE

This research illustrated that SH-PAN-19 is a promising chemotherapeutic agent capable of restoring cellular plasticity and could stop HCC progression.

Capsaicin: A chili pepper bioactive phytocompound with a potential role in suppressing cancer development and progression

Cancer profoundly influences morbidity and fatality rates worldwide. Patients often have dismal prognoses despite recent improvements in cancer therapy regimens. However, potent biomolecules derived from natural sources, including medicinal and dietary plants, contain biological and pharmacological properties to prevent and treat various human malignancies. Capsaicin is a bioactive phytocompound present in red hot chili peppers. Capsaicin has demonstrated many biological effects, including antioxidant, anti-inflammatory, antimicrobial, and anticarcinogenic capabilities. This review highlights the cellular and molecular pathways through which capsaicin exhibits antineoplastic activities. Our work also depicts the synergistic anticancer properties of capsaicin in conjunction with other natural bioactive components and approved anticancer drugs. Capsaicin inhibits proliferation in various cancerous cells, and its antineoplastic actions in numerous in vitro and in vivo carcinoma models impact oncogenesis, tumor-promoting and suppressor genes, and associated signaling pathways. Capsaicin alone or combined with other phytocompounds or approved antineoplastic drugs triggers cell cycle progression arrest, generating reactive oxygen species and disrupting mitochondrial membrane integrity, ultimately stimulating caspases and promoting death. Furthermore, capsaicin alone or in combination can promote apoptosis in carcinoma cells by enhancing the p53 and c-Myc gene expressions. In conclusion, capsaicin alone or in combination can have enormous potential for cancer prevention and intervention, but further high-quality studies are needed to firmly establish the clinical efficacy of this phytocompound.

Current progress of pig models for liver cancer research

Preclinical trials play critical roles in assessing the safety and efficiency of novel therapeutic strategies for human diseases including live cancer. However, most therapeutic strategies that were proved to be effective in preclinical cancer models failed in human clinical trials due to the lack of appropriate disease animal models. Therefore, it is of importance and urgent to develop a precise animal model for preclinical cancer research. Liver cancer is one of the most frequently diagnosed cancers with low 5-year survival rate. Recently, porcine attracted increasing attentions as animal model in biomedical research. Porcine liver cancer model may provide a promising platform for biomedical research due to their similarities to human being in body size, anatomical characteristics, physiology and pathophysiology. In this review, we comprehensively summarized and discussed the advantages and disadvantages, rationale, current status and progress of pig models for liver cancer research.

Critical Review in Designing Plant-Based Anticancer Nanoparticles against Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC), accounting for 85% of liver cancer cases, continues to be the third leading cause of cancer-related deaths worldwide. Although various forms of chemotherapy and immunotherapy have been investigated in clinics, patients continue to suffer from high toxicity and undesirable side effects. Medicinal plants contain novel critical bioactives that can target multimodal oncogenic pathways; however, their clinical translation is often challenged due to poor aqueous solubility, low cellular uptake, and poor bioavailability. Nanoparticle-based drug delivery presents great opportunities in HCC therapy by increasing selectivity and transferring sufficient doses of bioactives to tumor areas with minimal damage to adjacent healthy cells. In fact, many phytochemicals encapsulated in FDA-approved nanocarriers have demonstrated the ability to modulate the tumor microenvironment. In this review, information about the mechanisms of promising plant bioactives against HCC is discussed and compared. Their benefits and risks as future nanotherapeutics are underscored. Nanocarriers that have been employed to encapsulate both pure bioactives and crude extracts for application in various HCC models are examined and compared. Finally, the current limitations in nanocarrier design, challenges related to the HCC microenvironment, and future opportunities are also discussed for the clinical translation of plant-based nanomedicines from bench to bedside.

Nanoparticle-mediated TRPV1 channel blockade amplifies cancer thermo-immunotherapy via heat shock factor 1 modulation

The survival of malignant tumors is highly dependent on their intrinsic self-defense pathways such as heat shock protein (HSP) during cancer therapy. However, precisely dismantling self-defenses to amplify antitumor potency remains unexplored. Herein, we demonstrate that nanoparticle-mediated transient receptor potential vanilloid member 1 (TRPV1) channel blockade potentiates thermo-immunotherapy via suppressing heat shock factor 1 (HSF1)-mediated dual self-defense pathways. TRPV1 blockade inhibits hyperthermia-induced calcium influx and subsequent nuclear translocation of HSF1, which selectively suppresses stressfully overexpressed HSP70 for enhancing thermotherapeutic efficacy against a variety of primary, metastatic and recurrent tumor models. Particularly, the suppression of HSF1 translocation further restrains the transforming growth factor β (TGFβ) pathway to degrade the tumor stroma, which improves the infiltration of antitumor therapeutics (e.g. anti-PD-L1 antibody) and immune cells into highly fibrotic and immunosuppressive pancreatic cancers. As a result, TRPV1 blockade retrieves thermo-immunotherapy with tumor-eradicable and immune memory effects. The nanoparticle-mediated TRPV1 blockade represents as an effective approach to dismantle self-defenses for potent cancer therapy.

Research progress on the application of optical coherence tomography in the field of oncology

Optical coherence tomography (OCT) is a non-invasive imaging technique which has become the “gold standard” for diagnosis in the field of ophthalmology. However, in contrast to the eye, nontransparent tissues exhibit a high degree of optical scattering and absorption, resulting in a limited OCT imaging depth. And the progress made in the past decade in OCT technology have made it possible to image nontransparent tissues with high spatial resolution at large (up to 2mm) imaging depth. On the one hand, OCT can be used in a rapid, noninvasive way to detect diseased tissues, organs, blood vessels or glands. On the other hand, it can also identify the optical characteristics of suspicious parts in the early stage of the disease, which is of great significance for the early diagnosis of tumor diseases. Furthermore, OCT imaging has been explored for imaging tumor cells and their dynamics, and for the monitoring of tumor responses to treatments. This review summarizes the recent advances in the OCT area, which application in oncological diagnosis and treatment in different types: (1) superficial tumors:OCT could detect microscopic information on the skin’s surface at high resolution and has been demonstrated to help diagnose common skin cancers; (2) gastrointestinal tumors: OCT can be integrated into small probes and catheters to image the structure of the stomach wall, enabling the diagnosis and differentiation of gastrointestinal tumors and inflammation; (3) deep tumors: with the rapid development of OCT imaging technology, it has shown great potential in the diagnosis of deep tumors such in brain tumors, breast cancer, bladder cancer, and lung cancer.

Capsaicin: A Two-Decade Systematic Review of Global Research Output and Recent Advances Against Human Cancer

Capsaicin (8-methyl-N-vanillyl-6-nonenamide) is one of the most important natural products in the genus Capsicum. Due to its numerous biological effects, there has been extensive and increasing research interest in capsaicin, resulting in increased scientific publications in recent years. Therefore, an in-depth bibliometric analysis of published literature on capsaicin from 2001 to 2021 was performed to assess the global research status, thematic and emerging areas, and potential insights into future research. Furthermore, recent research advances of capsaicin and its combination therapy on human cancer as well as their potential mechanisms of action were described. In the last two decades, research outputs on capsaicin have increased by an estimated 18% per year and were dominated by research articles at 93% of the 3753 assessed literature. In addition, anti-cancer/pharmacokinetics, cytotoxicity, in vivo neurological and pain research studies were the keyword clusters generated and designated as thematic domains for capsaicin research. It was evident that the United States, China, and Japan accounted for about 42% of 3753 publications that met the inclusion criteria. Also, visibly dominant collaboration nodes and networks with most of the other identified countries were established. Assessment of the eligible literature revealed that the potential of capsaicin for mitigating cancer mainly entailed its chemo-preventive effects, which were often linked to its ability to exert multi-biological effects such as anti-mutagenic, antioxidant and anti-inflammatory activities. However, clinical studies were limited, which may be related to some of the inherent challenges associated with capsaicin in the limited clinical trials. This review presents a novel approach to visualizing information about capsaicin research and a comprehensive perspective on the therapeutic significance and applications of capsaicin in the treatment of human cancer.

Capsaicin suppresses hepatocarcinogenesis by inhibiting the stemness of hepatic progenitor cells via SIRT1/SOX2 signaling pathway

BACKGROUND & AIMS

Capsaicin, a functional component of chili pepper, possesses anti-inflammatory, analgesic, and anti-cancer properties. This study aimed to determine the property of capsaicin against hepatocarcinogenesis in vivo and investigate the role of the SIRT1/SOX2 pathway in the mode of action of capsaicin in hepatic progenitor cells (HPCs), which is related to hepatocarcinogenesis.

MATERIALS & METHODS

We prepared a diethylnitrosamine-induced liver cancer model in rats to examine hepatocarcinogenesis, and delivered liposomal capsaicin through the subcutaneous transposition of the spleen to the liver. Liver sections from rats and hepatocarcinoma patients were stained for the markers of HPCs or SIRT1/SOX2 signaling. SIRT1/SOX2 signalling expression was measured using immunoprecipitation and western blot.

RESULTS

We found that capsaicin significantly inhibited hepatocarcinogenesis. Notably, capsaicin inhibited HPCs activation in vivo but did not induce apoptosis in the normal hepatic progenitor cell line in rats in vitro. This suggests that capsaicin suppresses hepatocarcinogenesis by inhibiting the stemness of HPCs. Moreover, capsaicin can induce this inhibition by reducing the stability of SOX2. SIRT1 is overexpressed in liver cancer and acts as a tumor promoter via SOX2 deacetylation. Using immunoprecipitation, we identified direct binding between SIRT1 and SOX2. The capsaicin treatment resulted in SIRT1 downregulation which reduced deacetylation, and increased nuclear export as well as subsequent ubiquitous degradation of SOX2.

CONCLUSIONS

Altogether, we report that capsaicin suppresses hepatocarcinogenesis by inhibiting the stemness of HPCs via SIRT1/SOX2 signaling. It may serve as a promising therapeutic candidate for liver cancer.

Unveiling the Molecular Mechanisms Driving the Capsaicin-Induced Immunomodulatory Effects on PD-L1 Expression in Bladder and Renal Cancer Cell Lines

Simple Summary

Over time, capsaicin (CPS) has been considered both a potential anti-cancer and pro-cancer molecule. Hence, the diversity of CPS functioning has already been established. Now, exploration of its application with immunotherapies might open up a new avenue in cancer therapy. Herein, the application of CPS as an immunoadjuvant to overcome the tumor’s immune-escaping mechanisms or to increase immune checkpoint therapy has been approached. In bladder cancer, the interaction of CPS with its receptor TRPV1 increases PD-L1 expression, promoting a tumorigenic effect and also providing a target for anti-PD-1/PD-L1 immunotherapy. On the contrary, in renal cell carcinoma, CPS downregulates PD-L1 expression in a TRPV1-independent manner, suggesting a potential application of CPS as an immune-adjuvant in this type of cancer.

Abstract

The blockade of the PD-L1/PD-1 immune checkpoint has promising efficacy in cancer treatment. However, few patients with bladder cancer (BC) or renal cell carcinoma (RCC) respond to this approach. Thus, it is important to implement a strategy to stimulate the immune anti-tumor response. In this scenario, our study evaluated the effects of a low capsaicin (CPS) dose in BC and RCC cell lines. Western blot, qRT-PCR and confocal microscopy were used to assess PD-L1 mRNA and protein expression. Alterations to the cellular oxidative status and changes to the antioxidant NME4 levels, mRNA modulation of cytokines, growth factors, transcriptional factors and oncogene, and the activation of Stat1/Stat3 pathways were examined using Western blot, cytofluorimetry and qRT-PCR profiling assays. In BC, CPS triggers an altered stress oxidative-mediated DNA double-strand break response and increases the PD-L1 expression. On the contrary, in RCC, CPS, by stimulating an efficient DNA damage repair response, thus triggering protein carbonylation, reduces the PD-L1 expression. Overall, our results show that CPS mediates a multi-faceted approach. In modulating PD-L1 expression, there is a rationale for CPS exploitation as a stimulus that increases BC cells’ response to immunotherapy or as an immune adjuvant to improve the efficacy of the conventional therapy in RCC patients.

Capsaicinoid-Glucosides of Fresh Hot Pepper Promotes Stress Resistance and Longevity in Caenorhabditis elegans

In this study, capsaicin-glucoside and dihydro-capsaicin-glucoside derived from fresh hot-red pepper were isolated and identified using UPLC-ESI-Q-TOF-MS/PDA. Synchronized worms were treated with capsaicinoid-glucosides (CG), and then lifespan and stress resistance were examined. The 50 µg/ml concentration of CG-intake could effectively protect the Caenorhabditis elegans (C. elegans) against stresses factors including oxidation and heat as well as reactive oxygen species (ROS), thereby enhancing the survival of CG-treated worms under stress. Enhancing stress resistance in CG-treated worms could be due to the increased expressions of stress-related genes in C. elegans such as daf-16, skn-1 and their downstream target genes (sod-3, hsp-16.2, gst-4 and gcs-1). Lifespan study of different C. elegans strains and RT-PCR showed that the CG-mediated lifespan extension was dependent on DAF-16/FOXO and SKN-1/Nrf2 transcription factors. The study is a step forward in exploring the stress resistance and anti-aging properties of this beneficial extract. Thus, this study will be useful in formulating remedies for stresses factors and age associated disorders.

The Natural Chemotherapeutic Capsaicin Activates AMPK through LKB1 Kinase and TRPV1 Receptors in Prostate Cancer Cells

The natural bioactive compound capsaicin has been reported to have anticancer activity, although the underlying mechanism of action has not been completely clarified. Herein, we investigated the mechanism whereby capsaicin exerts antitumor effects on prostate cancer cells. We found that capsaicin activated AMP-activated kinase (AMPK) and promoted cell death in the LKB1-expressing prostate cancer cell lines LNCaP and PC3, but not in the liver kinase B1 (LKB1)-null cell line DU-145. Capsaicin treatment stimulated LKB1 phosphorylation and activated AMPK in LKB1-expressing cells. In addition, LKB1 silencing in LNCaP and PC3 cells abrogated capsaicin-induced AMPK activation, while the overexpression of LKB1 by lentiviral infection in DU-145 cells induced capsaicin-triggered AMPK phosphorylation. Moreover, the calcium/calmodulin-dependent kinase kinase 2 (CaMKK2) inhibitor STO-609 did not modify the activation of AMPK induced by capsaicin, suggesting a CaMKK2-independent mechanism. Capsaicin-induced LKB1 phosphorylation was dependent on the transient receptor potential cation channel subfamily V member 1 (TRPV1), since TRPV1 knocked down by shRNA abolished LKB1 and AMPK phosphorylation in LKB1-expressing cells. Altogether, our results showed that capsaicin affected AMPK activity in an LKB1- and TRPV1-dependent fashion, linking TRPV1 with cell fate. These data also suggest that capsaicin may be a rational chemotherapeutic option for prostate tumors.

Response of human cancer cells to simultaneous treatment with sorafenib and radiofrequency current

Due to their alleged analgesic, anti-inflammatory and tissue regenerative effects, capacitive-resistive electrothermal therapy (CRET), which is based on non-invasive exposure to radiofrequency (RF) currents, is often applied to chemotherapeutically treated patients with cancer. Our previous studies have demonstrated that subthermal CRET currents can elicit a number of cell responses, including anti-proliferative effects, in the human liver cancer cell line HepG2. Such effects involve significant changes in the regulation of proteins involved in MAPK signaling pathways, which are also implicated in the cancer cell response to standard anticancer drugs such as sorafenib. This overlap in response pathways may lead to competitive, neutralizing or blocking interactions between the electrical and chemical treatments, thus raising questions on the advisability of CRET treatment for their analgesic, anti-inflammatory or other purposes in patients undergoing chemotherapy. The present study analyzed the effects of simultaneous treatment with sorafenib and 448-kHz, subthermal CRET current on the proliferation and viability of HepG2 cell cultures. Cell viability was assessed through Trypan blue or XTT assays, while flow cytometry was applied for cell cycle and apoptosis analysis. The expression of proteins involved in cell proliferation were assessed by immunoblotting and immunofluorescence. The results revealed no evidence to suggest that the electrical treatment counteracted or neutralized the cellular response to sorafenib at the different conditions evaluated. Furthermore, at the standard pharmacological sorafenib concentration, 5 µM, the combined treatment elicited an anti-proliferative response significantly stronger than that induced by each of the treatments when applied separately in HepG2 cells. These data do not support the hypothesis that CRET exposure may inhibit or diminish the effects of a chemotherapeutic drug used in cancer treatment, and highlights the requirement for further investigation into the cell response to the combined action of electrical and chemical treatments.

Anti-Hepatocellular Carcinoma Biomolecules: Molecular Targets Insights

This report explores the available curative molecules directed against hepatocellular carcinoma (HCC). Limited efficiency as well as other drawbacks of existing molecules led to the search for promising potential alternatives. Understanding of the cell signaling mechanisms propelling carcinogenesis and driven by cell proliferation, invasion, and angiogenesis can offer valuable information for the investigation of efficient treatment strategies. The complexity of the mechanisms behind carcinogenesis inspires researchers to explore the ability of various biomolecules to target specific pathways. Natural components occurring mainly in food and medicinal plants, are considered an essential resource for discovering new and promising therapeutic molecules. Novel biomolecules normally have an advantage in terms of biosafety. They are also widely diverse and often possess potent antioxidant, anti-inflammatory, and anti-cancer properties. Based on quantitative structure-activity relationship studies, biomolecules can be used as templates for chemical modifications that improve efficiency, safety, and bioavailability. In this review, we focus on anti-HCC biomolecules that have their molecular targets partially or completely characterized as well as having anti-cancer molecular mechanisms that are fairly described.

Synergistic Activity of Capsaicin and Colistin Against Colistin-Resistant Acinetobacter baumannii: In Vitro/Vivo Efficacy and Mode of Action

Acinetobacter baumannii is an opportunistic pathogen predominantly associated with nosocomial infections. With emerging resistance against polymyxins, synergistic combinations of drugs are being investigated as a new therapeutic approach. Capsaicin is a common constituent of the human diet and is widely used in traditional alternative medicines. The present study evaluated the antibacterial activities of capsaicin in combination with colistin against three unrelated colistin-resistant Acinetobacter baumannii strains in vitro and in vivo, and then further studied their synergistic mechanisms. Using the checkerboard technique and time-kill assays, capsaicin and colistin showed a synergistic effect on colistin-resistant A. baumannii. A mouse bacteremia model confirmed the in vivo effects of capsaicin and colistin. Mechanistic studies shown that capsaicin can inhibit the biofilm formation of both colistin-resistant and non-resistant A. baumannii. In addition, capsaicin decreased the production of intracellular ATP and disrupted the outer membrane of A. baumannii. In summary, the synergy between these drugs may enable a lower concentration of colistin to be used to treat A. baumannii infection, thereby reducing the dose-dependent side effects. Hence, capsaicin–colistin combination therapy may offer a new treatment option for the control of A. baumannii infection.

Sorafenib for hepatocellular carcinoma: potential molecular targets and resistance mechanisms

Hepatocellular carcinoma (HCC) is the most widespread typical therapy-resistant, unresectable type of malignant solid tumour with a high death rate constituting huge medical concern. Sorafenib is a small molecule oral multi-target kinase potent inhibitor that acts by suppressing/blocking the multiplication of the tumour cells, angiogenesis, and encouraging apoptosis of the tumour cells. Though, the precise mechanism of tumour cell death induction by sorafenib is yet under exploration. Furthermore, genetic heterogeneity plays a critical role in developing sorafenib resistance, which leads the way to identify the need for predictive biomarkers responsible for drug resistance. Therefore, it is essential to find out the fundamental resistance mechanisms to expand therapeutic plans. The authors summarize the molecular concepts of resistance, progression, potential molecular targets, HCC management therapies, and discussion on the advancements expected in the coming future, inclusive of biomarker-driven treatment strategies, which may provide the prospects to design innovative therapeutically targeted strategies for the HCC treatment and the clinical implementation of emerging targeted agents.

The Impact of TRPV1 on Cancer Pathogenesis and Therapy: A Systematic Review

The transient receptor potential cation channel subfamily V member 1 (TRPV1) is a transmembrane protein that can be activated by various physical and chemical stimuli and is associated with pain transduction. In recent years, TRPV1 was discovered to play essential roles in cancer tumorigenesis and development, as TRPV1 expression levels are altered in numerous cancer cell types. Several investigations have discovered direct associations between TRPV1 and cancer cell proliferation, cell death, and metastasis. Furthermore, about two dozen TRPV1 agonists/antagonists are under clinical trial, as TRPV1 is a potential drug target for treating various diseases. Hence, more researchers are focusing on the effects of TRPV1 agonists or antagonists on cancer tumorigenesis and development. However, both agonists and antagonists may reveal anti-cancer effects, and the effect may function via or be independent of TRPV1. In this review, we provide an overview of the impact of TRPV1 on cancer cell proliferation, cell death, and metastasis, as well as on cancer therapy and the tumor microenvironment, and consider the implications of using TRPV1 agonists and antagonists for future research and potential therapeutic approaches.

Capsaicin on stem cell proliferation and fate determination - a novel perspective

Capsaicin (CAP), a member of the vanilloid family, is the main active component of chili peppers, which has been widely explored for its various pharmacological effects and influence on cell physiology, such as axonal growth and apoptosis of tumor cells. In particular, CAP plays a crucial role in determining the proliferation and fate specification of stem cells by modulating a variety of signaling pathways, such as PPARγ, C/EBPα and Notch signaling. Since CAP-mediated processes are complex and multifactorial, we hope to achieve a better understanding of these processes and their implications in clinical applications. This review aims to shed light on the influences and mechanisms of CAP on the actions of various stem cells in adults and discusses the role of CAP in the different process of stem cell behaviors, including proliferation and differentiation. Our purpose is to provide certain prospects for the application of CAP and stem cell therapy in treating diseases.

Synthesis of sorafenib analogues incorporating a 1,2,3-triazole ring and cytotoxicity towards hepatocellular carcinoma cell lines

A series of 1,2,3-triazole-containing Sorafenib analogues, in which the aryl urea moiety of Sorafenib (1) was replaced with a 1,2,3-triazole ring linking a substituted phenoxy fragment, were prepared successfully via Huisgen 1,3-dipolar cycloaddition and nucleophilic aromatic substitution. The studies of cytotoxicity towards human hepatocellular carcinoma (HCC) cell lines, HepG2 and Huh7, indicated that p-tert-butylphenoxy analogue 2m showed significant inhibitory activity against Huh7 with IC₅₀ = 5.67 ± 0.57 µM. More importantly, 2m showed low cytotoxicity against human embryonal lung fibroblast cell line, MRC-5, with IC₅₀ > 100 µM, suggesting its highly selective cytotoxic activity (SI > 17.6) towards Huh7 which is much superior to that of Sorafenib (SI = 6.73). The molecular docking studies revealed that the analogue 2m bound B-RAF near the binding position of Sorafenib, while it interacted VEGFR2 efficiently at the same binding position of Sorafenib. However, 2m exhibited moderate inhibitory activity toward B-RAF, implying that its anti-Huh7 effect might not strictly relate to inhibition of B-RAF. Wound healing and BrdU cell proliferation assays confirmed anti-cell migration and anti-cell proliferative activities towards Huh7. With its inhibitory efficiency and high safety profile, 2m has been identified as a promising candidate for the treatment of HCC.

Curry versus cancer: Potential of some selected culinary spices against cancer with in vitro, in vivo, and human trials evidences

Spices are dietary agents with immense potential for cancer chemo-prevention. A wide variety of spices are extensively used as food flavoring agents which possess potent antioxidant, anti-inflammatory, and anticancer properties due to the presence of certain bio-active compounds in them. In vitro, in vivo studies and clinical trials of selected spices against various types of cancer are being specified in this review. Effect of certain putative dietary spices namely turmeric, clove, garlic, ginger, fennel, black cumin, cinnamon, pepper, saffron, rosemary, and chilli along with its role in cancer are being discussed. Literature search was conducted through PubMed, Google scholar, Science direct, and Scopus using the keywords "spice," "cancer," "natural medicine," "herbal compound," "bioactive compounds." About 4,000 published articles and 127 research papers were considered to grab the brief knowledge on spices and their anticancer potential on a predefined inclusion and exclusion criteria. PRACTICAL APPLICATION: Historically, spices and herbs are known for its traditional flavor, odor, and medicinal properties. Intensified risk of chronic and pervasive clinical conditions and increased cost of advanced drug treatments have developed a keen interest among researchers to explore the miscellaneous properties of herbal spices. Cancer is one of the deleterious causes of mortality affecting a huge number of populations worldwide. Arrays of cancer treatments including surgery, chemotherapy, and radiation therapy are used to compromise the disease but effective only when the size of the tumor is small. So, an effective treatment need to be developed that produces less side effects and herbal spices are found to be the promising agents. In this review, we illustrate about different in vitro, in vivo, and clinical studies of wide range of culinary spices having antineoplastic potential.

The Effects of Capsaicin on Gastrointestinal Cancers

Gastrointestinal (GI) cancers are a group of diseases with very high positions in the ranking of cancer incidence and mortality. While they show common features regarding the molecular mechanisms involved in cancer development, organ-specific pathophysiological processes may trigger distinct signaling pathways and intricate interactions with inflammatory cells from the tumoral milieu and mediators involved in tumorigenesis. The treatment of GI cancers is a topic of increasing interest due to the severity of these diseases, their impact on the patients' survivability and quality of life, and the burden they set on the healthcare system. As the efficiency of existing drugs is hindered by chemoresistance and adverse reactions when administered in high doses, new therapies are sought, and emerging drugs, formulations, and substance synergies are the focus of a growing number of studies. A class of chemicals with great potential through anti-inflammatory, anti-oxidant, and anti-tumoral effects is phytochemicals, and capsaicin in particular is the subject of intensive research looking to validate its position in complementing cancer treatment. Our paper thoroughly reviews the available scientific evidence concerning the effects of capsaicin on major GI cancers and its interactions with the molecular pathways involved in the course of these diseases.

Synergistic antitumor activity of sorafenib and artesunate in hepatocellular carcinoma cells

Sorafenib is currently the standard chemotherapy drug for treatment of advanced hepatocellular carcinoma (HCC). But its efficacy requires improvement, it is imperative to seek therapeutic strategies that combine sorafenib with other anticancer agents. In this study we investigated the synergistic anticancer effect of combining sorafenib and artesunate, an anti-malaria drug derivative, against HCC in vitro and in vivo. We first showed that artesunate (1-100 μM) alone dose-dependently inhibited the proliferation of five HCC cell lines tested with IC₅₀ values of around 100 μM. Artesunate treatment dose-dependently increased the ROS level in both HuH7 and Hep3B cells; addition of NAC significantly ameliorated the antiproliferation effect of artesunate against HuH7 and Hep3B cells. Then we demonstrated that combination of sorafenib and artesunate exerted synergistic antiproliferation effect and induced synergistic apoptosis in HCC cell lines. In nude mice bearing Hep3B xenografts, combined administration of sorafenib and artesunate significantly enhanced the suppression on tumor growth. We further revealed that sorafenib dose-dependently decreased the levels of p-ERK and p-STAT3, whereas artesunate markedly increased the levels of p-ERK and p-STAT3 in HuH7 and Hep3B cells. When used in combination, sorafenib abolished artesunate-elevated levels of p-STAT3 and p-ERK. Moreover, pharmacological inhibition of ERK by inhibitor PD0325901 or STAT3 by inhibitor Stattic markedly enhanced the anticancer activity of artesunate, suggesting that suppression of ERK and STAT3 signaling by sorafenib contributes to the synergistic anticancer activity against HCC caused by combination of sorafenib and artesunate. Taken together, our results provide an evidence for possible use of sorafenib plus artesunate or artemisinin analogs for treatment of HCC in the future.

RP11-81H3.2 Acts as an Oncogene via microRNA-490-3p Inhibition and Consequential Tankyrase 2 Up-Regulation in Hepatocellular Carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is a serious threat to human lives and is usually diagnosed at the late stages. Recently, there has been a rapid advancement in the treatment options for HCC, but novel therapeutic targets are still needed, especially for precision medicine.

AIMS

We aimed to investigate the involvement of non-coding RNA RP11-81H3.2 in HCC.

METHODS

The expression of RP11-81H3.2 was examined in the blood samples of HCC patients, and in the human HCC cell lines, including HepG2, Smmc-7721, and Huh7. Cell proliferation was determined using the CCK-8 and EdU assay, and cell invasion and migration were determined using the transwell/wound healing assay. The effects of RP11-81H3.2 knockdown on in vivo tumor growth were evaluated utilizing the nude mice HepG2 tumor xenograft model.

RESULTS

Here, we have identified a long non-coding RNA, RP11-81H3.2, which is enriched in HCC and can promote its proliferation, migration, and invasion both in vitro and in vivo. In addition, our results showed that RP11-81H3.2 binds to and regulate miR-490-3p expression in the HCC cells. Moreover, we found that RP11-81H3.2 regulates the expression of TNKS2 via miR-490-3p. Further, we found that RP11-81H3.2 and miR-490-3p form a regulatory loop; the release of RP11-81H3.2 leads to the suppression of miR-490-3p expression, thus, further enhancing the expression of RP11-81H3.2.

CONCLUSIONS

Our data have provided a novel target for the diagnosis and treatment of HCC, and sheds light on the lncRNA-miRNA regulatory nexus that can control the HCC related pathogenesis.

The AC006262.5-miR-7855-5p-BPY2C axis facilitates hepatocellular carcinoma proliferation and migration

Hepatocellular carcinoma (HCC) is typically fatal, and patients with hepatocellular carcinoma are usually diagnosed at the late stages. Although the treatments for HCC have been rapidly advancing, novel targets for HCC are still desperately needed, especially for targeted therapies. Here, we identified an enriched long non-coding RNA, AC006262.5, associated with HCC, that promoted the proliferation, migration, and invasiveness of HCC cells, both in vitro and in vivo. In addition, our results revealed that AC006262.5 bound to and regulated miR-7855-5p, a tumor-suppressive miRNA, in HCC. Moreover, our data show that AC006262.5 regulates the expression of BPY2C via miR-7855-5p. Finally, we found that AC006262.5 and miR-7855-5p formed a regulatory loop. Upregulation of AC006262.5 resulted in decreased expression of miR-7855-5p, and downregulation of miR-7855-5p further facilitated the expression of AC006262.5. Our work provides novel targets for HCC diagnosis and treatment, and sheds light on the lncRNA-miRNA regulatory nexus that controls the pathology of HCC.

Inflammation, Cancer and Immunity-Implication of TRPV1 Channel

Process of inflammation and complex interactions between immune and cancer cells within tumor microenvironment are known to drive and shape the outcome of the neoplastic disease. Recent studies increasingly show that ion channels can be used as potential targets to modulate immune response and to treat inflammatory disorders and cancer. The action of both innate and adaptive immune cells is tightly regulated by ionic signals provided by a network of distinct ion channels. TRPV1 channel, known as a capsaicin receptor, was recently documented to be expressed on the cells of the immune system but also aberrantly expressed in the several tumor types. It is activated by heat, protons, proinflammatory cytokines, and associated with pain and inflammation. TRPV1 channel is not only involved in calcium signaling fundamental for many cellular processes but also takes part in cell-environment crosstalk influencing cell behavior. Furthermore, in several studies, activation of TRPV1 by capsaicin was associated with anti-cancer effects. Therefore, TRPV1 provides a potential link between the process of inflammation, cancer and immunity, and offers new treatment possibilities. Nevertheless, in many cases, results regarding TRPV1 are contradictory and need further refinement. In this review we present the summary of the data related to the role of TRPV1 channel in the process of inflammation, cancer and immunity, limitations of the studies, and directions for future research.

Capsaicinoids enhance chemosensitivity to chemotherapeutic drugs

Cytotoxic chemotherapy is the mainstay of cancer treatment. Conventional chemotherapeutic agents do not distinguish between normal and neoplastic cells. This leads to severe toxic side effects, which may necessitate the discontinuation of treatment in some patients. Recent research has identified key molecular events in the initiation and progression of cancer, promoting the design of targeted therapies to selectively kill tumor cells while sparing normal cells. Although, the side effects of such drugs are typically milder than conventional chemotherapies, some off-target effects still occur. Another serious challenge with all chemotherapies is the acquisition of chemoresistance upon prolonged exposure to the drug. Therefore, identifying supplementary agents that sensitize tumor cells to chemotherapy-induced apoptosis and help minimize drug resistance would be valuable for improving patient tolerance and response to chemotherapy. The use of effective supplementary agents provides a twofold advantage in combination with standard chemotherapy. First, by augmenting the activity of the chemotherapeutic drug it can lower the dose needed to kill tumor cells and decrease the incidence and severity of treatment-limiting side effects. Second, adjuvant therapies that lower the effective dose of chemotherapy may delay/prevent the development of chemoresistance in tumors. Capsaicinoids, a major class of phytochemical compounds isolated from chili peppers, have been shown to improve the efficacy of several anti-cancer drugs in cell culture and animal models. The present chapter summarizes the current knowledge about the chemosensitizing activity of capsaicinoids with conventional and targeted chemotherapeutic drugs, highlighting the potential use of capsaicinoids in novel combination therapies to improve the therapeutic indices of conventional and targeted chemotherapeutic drugs in human cancers.

Capsaicin: Effects on the Pathogenesis of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most frequent cancers, and to date, there have been very few drugs available that can improve survival, the most well-known being sorafenib. The pathogenesis of HCC is complex, involving multiple processes including abnormal cell and tissue regeneration, angiogenesis, genomic instability, cellular proliferation, and signaling pathway alterations. Capsaicin is a substance that holds increasingly high interest and is studied as a therapeutic option in a wide array of diseases. Several studies have investigated capsaicin roles in various stages of HCC oncogenesis. This paper aims to thoroughly detail the available information on the individual effects of capsaicin on the cellular mechanisms and pathways involved in HCC development, as well as investigate their possible cooperation and interferences. The synergistic antitumor effects of capsaicin and sorafenib are also addressed.

A facile approach for fabricating CD44-targeted delivery of hyaluronic acid-functionalized PCL nanoparticles in urethane-induced lung cancer: Bcl-2, MMP-9, caspase-9, and BAX as potential markers

Lung carcinoma ranks highest in cancer-related death (about 20% of total cancer deaths) due to poor prognosis and lack of efficient management therapy. Owing to the lack of effective therapeutic approaches, survival rate of less than 5 years persists over the years among non-small cell lung cancer (NSCLC) patients. Capsaicin (CAP) is well reported for its antiproliferative and antioxidant properties in various literature but lacks an appropriate delivery carrier. The present study was aimed to develop CAP-loaded hyaluronic acid (HA) nanoparticles (NPs) utilizing layer by layer technique to achieve enhanced and precise delivery as well as target specificity. The NPs were evaluated for in vitro release, particle size, zeta potential, and cytotoxicity on A549 cells. The optimized NPs exhibited a particle size of 194 ± 2.90 nm, - 27.87 ± 3.21 mV zeta potential, and 80.70 ± 4.29% release, respectively, over a period of 48 h. Flow cytometric analysis revealed superior performance of HA-PCL-CAP in terms of suppressed cell viability in A549 cell lines when compared with CAP and PCL-CAP. Further, HA-anchored NPs were evaluated in vivo for their therapeutic efficacy in urethane-induced lung carcinoma in rat model. The superlative therapeutic potential of HA-PCL-CAP was advocated from the results of reactive oxygen species and mitochondrial membrane-mediated apoptosis. HA-PCL-CAP-administered groups presented greater therapeutic efficacy as revealed through reduced tumor volume and improved animal survival rate. A greater drug accumulation in tumor tissue as revealed from biodistribution studies evidences targeting potential of HA-PCL-CAP in urethane-induced lung carcinoma. Graphical abstract ᅟ.

Novel HDAC6 selective inhibitors with 4-aminopiperidine-1- carboxamide as the core structure enhanced growth inhibitory activity of bortezomib in MCF-7 cells

In epigenetics, histone deacetylases (HDACs) are well validated targets for the development of anticancer drugs. In this work, we reported the design and synthesis of a series of twenty two novel (E)-N-hydroxycinnamamide-based HDAC inhibitors with 4-aminopiperidine1-carboxamide as the core structure. Most newly synthesized compounds displayed high inhibition rates toward HDAC at the concentration of 1 μM. Among them, the inhibition rates of compounds LYP-2, LYP-3, LYP-6, and LYP-15 were more than 75%. Furthermore, compounds LYP-2, LYP-3, and LYP-6 potently inhibited the activity of HDAC6 with selectivity over HDAC1. We chose LYP-2 and LYP-6 to test its antiproliferative effect on breast cancer cells MCF-7. Either LYP-2 or LYP-6 alone moderately suppressed the cell growth, but could synergistically enhance the inhibitory effect of bortezomib. These results suggested that combined HDAC6 inhibitor and bortezomib regimen might be an option for breast cancer treatment.

Animal models for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) represents ~90% of all cases of primary liver cancer and occurs predominantly in patients with underlying chronic liver disease and cirrhosis. Establishing appropriate animal models for HCC is required for basic and translational studies, especially the models that can recapitulate one of the human disease settings. Current animal models can be categorized as chemically-induced, genetically-engineered, xenograft, or a combination of these with each other or with a metabolic insult. A single approach to resemble human HCC in animals is not sufficient. Combining pathogenic insults in animal models may more realistically recapitulate the multiple etiologic agents occurring in humans. Combining chemical injury with metabolic disorder or alcohol consumption in mice reduces the time taken to hepatocarcinogenesis. Genetically-engineering weak activation of HCC-promoting pathways combined with disease-specific injury models will possibly mimic the pathophysiology of human HCC in distinct clinical settings.