Non-melanoma Skin Cancer Cells Research Articles

Abstract 5120: Cryptolepine a plant alkaloid, inhibits the growth of nonmelanoma skin cancer cells through inhibition of topoisomerase and induction of DNA damage

Abstract Topoisomerases are highly specialized nuclear enzymes that remove superhelical tension on chromosomal DNA that allows replication and transcription of DNA. Many cancer chemotherapeutic drugs used in the clinics inhibit tumor growth by targeting topoisomerase functions resulting in DNA damage and cancer cell death. Cryptolepine, a major alkaloid isolated from Cryptolepis sanguinolenta plant’s roots, has shown anti-malarial, anti-bacterial, anti-fungal, and anti-inflammatory activities. In the present study, we examined the therapeutic effect of cryptolepine on non-melanoma skin cancer cells (NMSCC), SCC-13 and A431 as an in vitro model, and underlying mechanism of action with special emphasis on topoisomerases and DNA damage check points. Western blot analysis and enzyme activity evaluation assays demonstrated that SCC-13 and A431 cells express comparatively higher levels of topoisomerases and higher enzymatic activities compared with normal human epidermal keratinocytes (NHEK). Topoisomerase expression and activity was greatly reduced after 24 h treatment with 2.5, 5.0 and 7.5 µM cryptolepine. Inhibition of topoisomerases expression and function by cryptolepine resulted in significant DNA damage and enhanced expression of DNA-PK expressions. Cryptolepine induced DNA damage activated DNA damage response proteins as demonstrated by increased phosphorylation of ATM/ATR, BRCA1, Chk1/Chk2 and γH2AX. Consequences of cryptolepine induced DNA damage were also associated with activation of p53 signaling cascade. Cryptolepine induced post-translational modifications such as phosphorylation and acetylation of p53, and inhibition of mdm2 protein expression resulted in activation and accumulation of p53 in SCC-13 and A431 cells. In turn, activated p53 enhanced protein expression of cyclin-dependent kinase inhibitors p16 and p21. Activation of p16 and p21 proteins downregulated expression of cyclin-dependent kinase 2 (CDK2), cyclin A, cyclin D1 and cyclin E and thus induced S-phase cell cycle arrest in NMSC cells with reduced expression of cell division proteins Cdc25a and Cdc25b. Cryptolepine treatment also enhanced release of cytochrome c from mitochondria due to increased disruption of mitochondrial membrane potential. Inhibition of topoisomerase activity and activation of DNA damage response signaling culminated in significantly reduced cell viability and enhanced cell death of SCC-13 and A431 cells. However, NHEK cells were least sensitive to cryptolepine induced cell death. Results of our study strongly suggest for detailed preclinical investigations in animal models to further assess its anti-skin cancer potential and its possible use in human patients. Note: This abstract was not presented at the meeting. Citation Format: Harish C. Pal, Santosh K. Katiyar. Cryptolepine a plant alkaloid, inhibits the growth of nonmelanoma skin cancer cells through inhibition of topoisomerase and induction of DNA damage [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5120. doi:10.1158/1538-7445.AM2017-5120

Abstract 123: A novel J-series prostamide mediates D-series prostamide-induced apoptosis in skin cancer: receptor-independent signaling

Abstract Non-melanoma skin cancer (NMSC) is the most common cancer in the United States. The absence of selective toxicity is a major problem that limits the utility of chemotherapeutic and radiation therapy for NMSCs. Our previous data showed that the endocannabinoid, anandamide, selectively induced apoptosis in non-melanoma skin cancer (NMSC) cells which overexpress cyclooxygenase-2. The cytotoxic effect of anandamide was mediated by the production of ethanolamide-conjugated D- and J-series prostaglandins (PGs), also known as prostamide D2 (PMD2) and prostamide J2 (PMJ2), respectively. The aim of the current study was to determine if tumorigenic keratinocytes are more sensitive to PMD2 than non-tumorigenic cells and to examine whether the cytotoxicity of PMD2 is mediated by its downstream metabolite PMJ2. To determine if PMD2 demonstrates preferential toxicity, tumorigenic (JWF2) and non-tumorigenic (HaCaT) keratinocytes were utilized. A significant reduction in cell viability was observed in JWF2 but not in HaCaT cells treated with PMD2. In tumorigenic keratinocytes, PMD2 induced apoptotic cell death, oxidative stress and increased the expression of apoptotic ER stress protein, C/EBP homologous protein-10 (CHOP10). In addition, use of the antioxidant, trolox, and ER stress inhibitor, salubrinal, inhibited the cytotoxic effect of PMD2. Furthermore, the use of prostaglandin D receptor (DP1 and DP2) antagonists did not inhibit PMD2-induced apoptosis indicating that the activity was mediated by a receptor-independent pathway. Similar effects were observed in keratinocytes treated with the structurally-related arachidonic acid metabolite, prostaglandin D2 (PGD2). Interestingly, PMD2 increased the production of J-series prostaglandins in both tumorigenic and non-tumorigenic keratinocytes. LC-ESI-MS/MS analysis detected ethanolamide- conjugated J series PG (15-deoxy, Δ12,14 prostamide J2, 15d-PMJ2) in PMD2-treated cell culture media. Since selective inhibitors of the J-series prostaglandins are not available, 15d-PMJ2 was synthesized to examine its direct activity. Exogenous 15d-PMJ2 mimicked the activity of PMD2 demonstrating preferential cytotoxicity towards tumorigenic compared to non-tumorigenic keratinocytes. In addition, 15d-PMJ2 induced oxidative stress, ER stress and apoptosis in tumorigenic keratinocytes. These findings suggest that the cytotoxicity of PMD2 is mediated by 15dPMJ2. Since PMD2 and its metabolite 15d-PMJ2 are preferentially toxic towards tumorigenic cells, PMD2 or 15d-PMJ2 may be an ideal topical treatment for NMSC that will elicit minimal toxicity in healthy surrounding skin cells. Citation Format: Eman Soliman, Daniel Ladin, Hussam Albassam, Ahmed E. Elhassanny, Andrew Morris, Allison Danell, Rukiyah Van Dross. A novel J-series prostamide mediates D-series prostamide-induced apoptosis in skin cancer: receptor-independent signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 123. doi:10.1158/1538-7445.AM2017-123

The mechanism of CIRP in inhibition of keratinocytes growth arrest and apoptosis following low dose UVB radiation.

UV induces CIRP expression and subsequent Stat3 activation, but the biological function and mechanism of CIRP and Stat3 in mediating UVB-induced skin carcinogenesis have not been fully elucidated. In this study, we demonstrate that CIRP is elevated in all tested melanoma and non-melanoma skin cancer cell lines; and the expression of CIRP is upregulated in keratinocytes after being irradiated with relatively low dose (<5 mJ/cm2 ), but not high dose (50 mJ/cm2 ), UVB acutely and chronically. The increased expression of CIRP, either induced by UVB or through overexpression, leads to resistance of keratinocytes to UVB-induced growth arrest and death; and reduced expression of CIRP by RNA knockdown sensitizes keratinocyte cells to the low dose UVB radiation. We also demonstrated that CIRP expression is required for the low dose UVB-induced Tyr705-phosphorylation, but not total amount, of Stat3. The p-Stat3 level is correlated with the expression levels of cyclin D1 and VEGF, two known downstream cell growth regulators of Stat3, as well as Bag-1/S, an apoptosis regulator. Inhibition of Stat3 DNA-binding activity by S3I-201 leads to a reduction of the p-Stat3 and Bag-1/S along with growth and survival of keratinocytes post-UVB; and the effect of S3I-201 on the UVB-irradiated cells can be partially inhibited by overexpression of CIRP or Bag-1/S. Furthermore, the overexpression of Bag-1/S can totally inhibit UVB-induced PARP cleavage and caspase 3 activation. The results presented above led us to propose that CIRP-p(705)Stat3 cascade promotes cell proliferation and survival post-UVB via upregulating the expression of cyclin D1 and Bag-1/S, respectively. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

Cytotoxic effect of chamomile (Matricaria recutita) and marigold (Calendula officinalis) extracts on human melanoma SK-MEL-2 and epidermoid carcinoma KB cells

The aim of the present study was to evaluate the potential anticancer action of extracts prepared from german chamomile (Matricaria recutita L.)and pot marigold (Calendula officinalis L.) to human melanoma and epidermoid carcinoma cells. Sulforhodamine B assay was used to measure the cytotoxic activity of methanolic extracts from flowers of chamomile and marigold. The cytotoxic activity of extract of chamomile flowers on melanoma cells (IC50 value 40.7 μg/ml) was approximately twofold higher than on epidermoid carcinoma cells (IC50 value 71.4 μg/ml). In the present study, the anticancer action of extracts prepared from german chamomile flowers on human melanoma and non-melanoma skin cancer cells (SK-MEL-2 melanoma and KB epidermoid carcinoma cells) is described for the first time.

Cryptolepine, a Plant Alkaloid, Inhibits the Growth of Non-Melanoma Skin Cancer Cells through Inhibition of Topoisomerase and Induction of DNA Damage.

Topoisomerases have been shown to have roles in cancer progression. Here, we have examined the effect of cryptolepine, a plant alkaloid, on the growth of human non-melanoma skin cancer cells (NMSCC) and underlying mechanism of action. For this purpose SCC-13 and A431 cell lines were used as an in vitro model. Our study reveals that SCC-13 and A431 cells express higher levels as well as activity of topoisomerase (Topo I and Topo II) compared with normal human epidermal keratinocytes. Treatment of NMSCC with cryptolepine (2.5, 5.0 and 7.5 µM) for 24 h resulted in marked decrease in topoisomerase activity, which was associated with substantial DNA damage as detected by the comet assay. Cryptolepine induced DNA damage resulted in: (i) an increase in the phosphorylation of ATM/ATR, BRCA1, Chk1/Chk2 and γH2AX; (ii) activation of p53 signaling cascade, including enhanced protein expressions of p16 and p21; (iii) downregulation of cyclin-dependent kinases, cyclin D1, cyclin A, cyclin E and proteins involved in cell division (e.g., Cdc25a and Cdc25b) leading to cell cycle arrest at S-phase; and (iv) mitochondrial membrane potential was disrupted and cytochrome c released. These changes in NMSCC by cryptolepine resulted in significant reduction in cell viability, colony formation and increase in apoptotic cell death.

Abstract B30: Resistance to Photodynamic Therapy in Non-Melanoma Skin Cancer Cells

Abstract Introduction: Squamous skin cancer is one of the most common neoplasia worldwide and may be preceded by Bowen's disease (BD) and Actinic Keratosis (AK). These preneoplastic lesions can be treated with photodynamic therapy (PDT). PDT causes cell death mainly by reactive oxygen species (ROS) produced through a combination of O2, a photosensitizer and light. BD and AK have well overcomes after PDT. However, high recurrence rates of some lesions have been reported. Objective: To generate resistant cells to PDT as an in vitro model for future studies. Methodology: HSC-1 cells from human squamous cell cancer (SCC) of skin were used. Cells were treated with a total of 16 cycles of PDT. Every PDT cycle was carried out incubating cells with methyl aminolevulinate (MAL), as a protoporphyrin IX (PpIX) precursor, for 4 hours in the dark. Then, cells were irradiated with red light (630 nm). The light fluence used for the four first cycles was 1 J/cm2, for subsequent cycles light fluence increased to 2, 3 and 4 J/cm2. Cell viability was evaluated 1 and 24 hours after PDT by flow cytometry and MTT assay respectively. Intracellular PpIX was detected by flow cytometry and the PpIX content was quantified using a standard curve. By flow cytometry using a CM-H2DCFDA probe intracellular ROS was detected. Results: After 24 hours of PDT (4 J/cm2), viability in parental HSC-1 cells was 5%, meanwhile in resistant cells was 70% (P &amp;lt; 0.05). On the other hand, 88% of parental cells produced PpIX (40 ng/mg protein) and 18% of resistant cells produced PpIX (17 ng/mg protein) (P &amp;lt; 0.05). No significant differences were found in ROS detection in both parental and resistant cells. Conclusion: The results indicate that it was possible to obtain HSC-1 cells two-fold resistant to PDT compared to their parental cells. Acknowledgments: Financial support by CONICYT. CONICYT-PCHA/Doctorado Nacional/2012-21120665, CORFO 09CN14-5960, Corfo N°12IDL2-18157, FONDECYT N° 11150802, FONDECYT N°11150622. Citation Format: Daniela Leon, Ramon Silva, Natalia Inada, Cristina Kurachi, Carmen Gloria Ili, Priscilla Brebi, Juan Carlos Roa. Resistance to Photodynamic Therapy in Non-Melanoma Skin Cancer Cells. [abstract]. In: Proceedings of the AACR Precision Medicine Series: Cancer Cell Cycle - Tumor Progression and Therapeutic Response; Feb 28-Mar 2, 2016; Orlando, FL. Philadelphia (PA): AACR; Mol Cancer Res 2016;14(11_Suppl):Abstract nr B30.

Abstract LB-028: CIRP promotes keratinocytes survival following low-dose UVB irradiation through Stat3-mediated Bag-1/S expression

Abstract UV induces CIRP expression and subsequent Stat3 activation, but the biological function and mechanism of CIRP and Stat3 in mediating UVB-induced skin carcinogenesis have not been fully elucidated. In this study, we demonstrate that CIRP is elevated in all tested melanoma and non-melanoma skin cancer cell lines; and the expression of CIRP is upregulated in keratinocytes after being irradiated with relatively low dose (&amp;lt;5 mJ/cm2), but not high dose (50 mJ/cm2), UVB acutely and chronically. The increased expression of CIRP, either induced by UVB or through overexpression, leads to resistance of keratinocytes to UVB-induced growth arrest and death; and reduced expression of CIRP by RNA knockdown sensitizes keratinocyte cells to the low dose UVB irradiation. We also demonstrated that CIRP expression is required for the low dose UVB-induced Tyr705-phosphorylation, but not total amount, of Stat3. The p-Stat3 level is correlated with the expression levels of cyclin D1 and VEGF, two known downstream cell growth regulators of Stat3, as well as Bag-1/S, an apoptosis regulator. Inhibition of Stat3 DNA-binding activity by S3I-201 leads to a reduction of the p-Stat3 and Bag-1/S along with growth and survival of keratinocytes post-UVB; and the effect of S3I-201 on the UVB-irradiated cells can be partially inhibited by overexpression of CIRP or Bag-1/S. Furthermore, the overexpression of Bag-1/S can totally inhibit UVB-induced PARP cleavage and caspase 3 activation. The results presented above led us to propose that CIRP-p(705)-Stat3 cascade promotes cell proliferation and survival post-UVB via upregulating the expression of cyclin D1 and Bag-1/S respectively. Citation Format: Yi Liao, Liling Tang, Shiyong Wu. CIRP promotes keratinocytes survival following low-dose UVB irradiation through Stat3-mediated Bag-1/S expression. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-028.

Solamargine triggers cellular necrosis selectively in different types of human melanoma cancer cells through extrinsic lysosomal mitochondrial death pathway.

BackgroundPrevious reports showed that the Steroidal Glycoalkaloid Solamargine inhibited proliferation of non-melanoma skin cancer cells. However, Solamargine was not tested systematically on different types of melanoma cells and was not simultaneously tested on normal cells either. In this study we aimed to investigate the effect of Solamargine and the mechanism involved in inhibiting the growth of different types of melanoma cells.MethodsSolamargine effect was tested on normal cells and on another three melanoma cell lines. Vertical growth phase metastatic and primary melanoma cell lines WM239 and WM115, respectively and the radial growth phase benign melanoma cells WM35 were used. The half inhibitory concentration IC50 of Solamargine was determined using Alamarblue assay. The cellular and subcellular changes were assessed using light and Transmission Electron Microscope, respectively. The percentage of cells undergoing apoptosis and necrosis were measured using Flow cytometry. The different protein expression was detected and measured using western blotting. The efficacy of Solamargine was determined by performing the clonogenic assay. The data collected was analyzed statistically on the means of the triplicate of at least three independent repeated experiments using one-way ANOVA test for parametric data and Kruskal–Wallis for non-parametric data. Differences were considered significant when the P values were less than 0.05.ResultsHereby, we demonstrate that Solamargine rapidly, selectively and effectively inhibited the growth of metastatic and primary melanoma cells WM239 and WM115 respectively, with minimum effect on normal and benign WM35 cells. Solamargine caused cellular necrosis to the two malignant melanoma cell lines (WM115, WM239), by rapid induction of lysosomal membrane permeabilization as confirmed by cathepsin B upregulation which triggered the extrinsic mitochondrial death pathway represented by the release of cytochrome c and upregulation of TNFR1. Solamargine disrupted the intrinsic apoptosis pathway as revealed by the down regulation of hILP/XIAP, resulting in caspase-3 cleavage, upregulation of Bcl-xL, and Bcl2, and down regulation of Apaf-1 and Bax in WM115 and WM239 cells only. Solamargine showed high efficacy in vitro particularly against the vertical growth phase melanoma cells.ConclusionOur findings suggest that Solamargine is a promising anti-malignant melanoma drug which warrants further attention.Electronic supplementary materialThe online version of this article (doi:10.1186/s12935-016-0287-4) contains supplementary material, which is available to authorized users.

Anandamide-induced endoplasmic reticulum stress and apoptosis are mediated by oxidative stress in non-melanoma skin cancer: Receptor-independent endocannabinoid signaling.

Endocannabinoids are neuromodulatory lipids that regulate central and peripheral physiological functions. Endocannabinoids have emerged as effective antitumor drugs due to their ability to induce apoptosis in various cancer studies. The G-protein coupled cannabinoid receptors (CB1 and CB2) and the TRPV1 ion channel were reported to mediate the antiproliferative activity of endocannabinoids. However, receptor-independent effects also account for their activity. Our previous studies showed that the antiproliferative activity of anandamide (AEA) was regulated by cyclooxygenase-2 (COX-2) via induction of endoplasmic reticulum (ER) stress. We also determined that AEA induced oxidative stress. However, the role of oxidative stress, the cannabinoid receptors, and TRPV1 in AEA-induced ER stress-apoptosis was unclear. Therefore, the current study examines the role of oxidative stress in ER stress-apoptosis and investigates whether this effect is modulated by CB1, CB2, or TRPV1. In non-melanoma skin cancer (NMSC) cells, AEA reduced the total intracellular level of glutathione and induced oxidative stress. To evaluate the importance of oxidative stress in AEA-induced cell death, the antioxidants, N-acetylcysteine (NAC) and Trolox, were utilized. Each antioxidant ameliorated the antiproliferative effect of AEA. Furthermore, Trolox inhibited AEA-induced CHOP10 expression and caspase 3 activity, indicating that oxidative stress was required for AEA-induced ER stress-apoptosis. On the other hand, selective blockade of CB1, CB2, and TRPV1 did not inhibit AEA-induced oxidative stress or ER stress-apoptosis. These findings suggest that AEA-induced ER stress-apoptosis in NMSC cells is mediated by oxidative stress through a receptor-independent mechanism. Hence, receptor-independent AEA signaling pathways may be targeted to eliminate NMSC. © 2015 Wiley Periodicals, Inc.

Comparison of the response and mechanisms of MAL-PDT of different squamous carcinoma cell lines

Comparison of the response and mechanisms of MAL-PDT of different squamous carcinoma cell lines

Monitoring of the PDT by infrared images – A clinic study

Monitoring of the PDT by infrared images – A clinic study

Unveiling the molecular mechanisms involved in the cytotoxicity induced by photodynamic therapy in human breast cancer cells

Unveiling the molecular mechanisms involved in the cytotoxicity induced by photodynamic therapy in human breast cancer cells

Non-melanoma Skin Cancer in Canada Chapter 1: Introduction to the Guidelines.

Non-melanoma skin cancer (NMSC), including basal and squamous cell carcinoma, represents the most common malignancy. The aim of this document is to provide guidance to Canadian health care practitioners on NMSC management. After conducting a literature review, the group developed recommendations for prevention, management, and treatment of basal cell carcinomas, squamous cell carcinomas, and actinic keratoses. These tumour types are considered separately in the accompanying articles. The Grading of Recommendations Assessment, Development and Evaluation system was used to assign strength to each recommendation. This introduction describes the scope and structure of the guidelines and the methods used to develop them. The epidemiology of NMSC is reviewed, as are the pathophysiologic changes occurring with damage to the skin, which lead to the formation of actinic keratoses and invasive squamous or basal cell carcinomas. This introduction describes the need for primary prevention and offers an overview of treatment options that are discussed in later chapters of the guidelines.

Non-melanoma Skin Cancer in Canada Chapter 2: Primary Prevention of Non-melanoma Skin Cancer.

Non-melanoma skin cancer (NMSC), including basal and squamous cell carcinoma (BCC and SCC), represents the most common malignancy. To provide guidance to Canadian health care practitioners regarding primary prevention of NMSC. Structured literature searches were conducted, using search terms including prevention, sunscreen, and sun prevention factor. All recommendations concern guidance that physicians should regularly discuss with their patients to help establish photoprotection habits. The GRADE system was used to assign strength to each recommendation. Ultraviolet exposure is the major modifiable risk factor for NMSC. Aspects of photoprotection, including effective sunscreen use and avoidance of both the midday sun and artificial tanning, are discussed. Several widespread misunderstandings that undermine responsible public health measures related to sun safety are addressed. Photoprotection represents both an individual priority and a public health imperative. By providing accurate information during routine patient visits, physicians reinforce the need for ongoing skin cancer prevention.

Th17 cytokines in non-melanoma skin cancer.

T-helper-type 17 cytokines have been implicated in epithelial cancer progression at mucosal sites. In this issue of the European Journal of Immunology, Nardinocchi et al. [Eur. J. Immunol. 2015. 45: 922-931] show that the Th17 cytokines IL-17 and IL-22 can both signal to nonmelanoma skin cancer cells, inducing both cellular proliferation and enhanced migration of human basal cell carcinoma and squamous cell carcinoma cell lines in vitro. These cytokines were also shown to exacerbate tumor growth in mice injected with the squamous cell carcinoma line, CAL27. Thus, IL-17 and IL-22 may be key factors in skin cancer progression and may provide novel prognostic markers in nonmelanoma skin cancer.

Id3 induces an Elk-1-caspase-8-dependent apoptotic pathway in squamous carcinoma cells.

Inhibitor of differentiation/DNA-binding (Id) proteins are helix–loop–helix (HLH) transcription factors. The Id protein family (Id1–Id4) mediates tissue homeostasis by regulating cellular processes including differentiation, proliferation, and apoptosis. Ids typically function as dominant negative HLH proteins, which bind other HLH proteins and sequester them away from DNA promoter regions. Previously, we have found that Id3 induced apoptosis in immortalized human keratinocytes upon UVB exposure, consistent with its role as a tumor suppressor. To investigate the role of Id3 in malignant squamous cell carcinoma (SCC) cells (A431), a tetracycline-regulated inducible system was used to induce Id3 in cell culture and mouse xenograft models. We found that upon Id3 induction, there was a decrease in cell number under low serum conditions, as well as in soft agar. Microarray, RT-PCR, immunoblot, siRNA, and inhibitor studies revealed that Id3 induced expression of Elk-1, an E-twenty-six (ETS)-domain transcription factor, inducing procaspase-8 expression and activation. Id3 deletion mutants revealed that 80 C-terminal amino acids, including the HLH, are important for Id3-induced apoptosis. In a mouse xenograft model, Id3 induction decreased tumor size by 30%. Using immunofluorescent analysis, we determined that the tumor size decrease was also mediated through apoptosis. Furthermore, we show that Id3 synergizes with 5-FU and cisplatin therapies for nonmelanoma skin cancer cells. Our studies have shown a molecular mechanism by which Id3 induces apoptosis in SCC, and this information can potentially be used to develop new treatments for SCC patients.

Antioxidant, anti-adipocyte differentiation, antitumor activity and anthelminticactivities against Anisakis simplex and Hymenolepis nana ofyakuchinone A from Alpinia oxyphylla

BackgroundAlpinia oxyphylla is a common remedy in traditional Chinese medicine. Yakuchinone A is a major constituent of A. oxyphylla and exhibits anti-inflammatory, antitumor, antibacterial, and gastric protective activities.MethodsAntioxidant and antitumor characteristics of yakuchinone A in skin cancer cells as well as novel mechanisms for the inhibition of adipocyte differentiation, cestocidal activities against Hymenolepis nana adults, and nematocidal activities against Anisakis simplex larvae are investigated.ResultsYakuchinone A presents the ability of the removal of DPPH·and ABTS+ free radicals and inhibition of lipid peroxidation. Yakuchinone A suppresses intracellular lipid accumulation during adipocyte differentiation in 3 T3-L1 cells and the expressions of leptin and peroxisome proliferator-activated receptor γ (PPARγ). Yakuchinone A induces apoptosis and inhibits cell proliferation in skin cancer cells. The inhibition of cell growth by yakuchinone A is more significant for non-melanoma skin cancer (NMSC) cells than for melanoma (A375 and B16) and noncancerous (HaCaT and BNLCL2) cells. Treatment BCC cells with yakuchinone A shows down-regulation of Bcl-2, up-regulation of Bax, and an increase in cleavage poly (ADP-ribose) polymerase (PARP). This suggests that yakuchinone A induces BCC cells apoptosis through the Bcl-2-mediated signaling pathway. The anthelmintic activities of yakuchinone A for A. simplex are better than for H. nana.ConclusionsIn this work, yakuchinone A exhibits antioxidative properties, anti-adipocyte differentiation, antitumor activity, and anthelmintic activities against A. simplex and H. nana.

Cav1 Suppresses Tumor Growth and Metastasis in a Murine Model of Cutaneous SCC through Modulation of MAPK/AP-1 Activation

Caveolin-1 (Cav1) is a scaffolding protein that serves to regulate the activity of several signaling molecules. Its loss has been implicated in the pathogenesis of several types of cancer, but its role in the development and progression of cutaneous squamous cell carcinoma (cSCC) remains largely unexplored. Herein, we use the keratinocyte cell line PAM212, a murine model of cSCC, to determine the function of Cav1 in skin tumor biology. We first show that Cav1 overexpression decreases cell and tumor growth, whereas Cav1 knockdown increases these attributes in PAM212 cells. In addition, Cav1 knockdown increases the invasive ability and incidence of spontaneous lymph node metastasis. Finally, we demonstrate that Cav1 knockdown increases extracellular signaling-related kinase 1/2 mitogen-activated protein kinase/activator protein-1 pathway activation. We attribute the growth and invasive advantage conferred by Cav1 knockdown to increased expression of activator protein-1 transcriptional targets, including cyclin D1 and keratin 18, which show inverse expression in PAM212 based on the expression level of Cav1. In summary, we demonstrate that loss of Cav1 affects several characteristics associated with aggressive human skin tumors and that this protein may be an important modulator of tumor growth and invasion in cSCC.

Lifestyle factors of smoking, BMI and alcohol on the risk of Non-Melanoma Skin Cancer in adults: a systematic review.

Non-melanoma skin cancer is the most common cancer in humans and the most important risk factors are thought to be age, skin type, and exposure to ultraviolet radiation. Lifestyle factors may also play a part. To date no systematic review has been performed to collate evidence of the effects of smoking, alcohol or body mass index. We performed a systematic review and meta-analysis to assess the effects of smoking, alcohol and body mass index on the risk of non-melanoma skin cancer and its subtypes. Adults (18+ years old) of either sex from any ethnicitySmoking, alcohol, or body mass index (including other anthropometric measurements, such as weight, waist to hip ratio, and the percentage body fat)Non-melanoma skin cancer, cutaneous squamous cell carcinoma, or basal cell carcinomaComparative observational epidemiological studies SEARCH STRATEGY: We performed a comprehensive search of MEDLINE, EMBASE, CINAHL, Cochrane Library and CAB Abstracts from inception to October 2010. We also scanned reference lists to identify further eligible studies. Data from eligible studies were extracted and quality assessed using the Newcastle Ottawa Scale independently by two reviewers. The titles, abstracts and full text identified from the search were assessed independently by two reviewers against pre-specified inclusion/exclusion criteria. Disagreements were resolved through discussion with a third reviewer. For studies with similar exposures, a meta-analysis was performed using a random effects model and results were expressed as pooled odds ratio with 95% confidence intervals. Heterogeneity was assessed using I. Publication bias was assessed using funnel plots. Data were analysed using Review Manager. Thirty studies were included of which 22 used a case control design and the remaining used a cohort design. The overall quality of the studies was variable with a Newcastle Ottawa Scale median score of 6 out of 9 stars. No evidence of asymmetry was detected in the funnel plots. Smoking was not significantly related to increased risks of non-melanoma skin cancer (Odds Ratio 0.62, 95% CI 0.21 to 1.79, I=34%, 2 studies) or basal cell carcinoma (Odds Ratio 0.95, 95% CI 0.82 to 1.09; I=59%, 14 studies). However, smoking was significantly associated with a 52% increase in the risk of cutaneous squamous cell carcinoma (95% CI 1.15 to 2.01; I=64%; 6 studies). Subgroup analysis found no significant difference in results based on the definition of smoking (current, former, or ever smoker) for basal cell carcinoma, cutaneous squamous cell carcinoma or non-melanoma skin cancer. Alcohol was not significantly related to increased risks of non-melanoma skin cancer (1 study), basal cell carcinoma (Odds Ratio 1.03, 95% CI 0.94 to 1.13, I=0%, 9 studies) or cutaneous squamous cell carcinoma (1 study). Similar results were found irrespective of the type of alcohol assessed (beer, wine, or spirits) for basal cell carcinoma and cutaneous squamous cell carcinoma. A pooled analysis of five studies found a non-significant decrease in the risk of basal cell carcinoma associated with a higher body mass index (Odds Ratio 0.94, 95% CI 0.84 to 1.04, I=40%). In a subgroup analysis based on sex, the potential reduction in risk of basal cell carcinoma appeared to be confined to males (Males: Odds Ratio 0.90, 95% CI 0.78 to 1.04, I=45%, 4 studies; Females: Odds Ratio 1.01, 95% CI 0.85 to 1.19, I=14%, 3 studies). It is unclear at present if smoking modifies the risk of basal cell carcinoma; however, smoking clearly increases the risk of cutaneous squamous cell carcinoma. Limited evidence has been published about the risk of non-melanoma skin cancer with alcohol and body mass index; however there is some suggestion a high body mass index may be slightly protective of basal cell carcinoma, particularly in males.This study highlights the importance for clinicians to actively survey high risk patients, including current smokers.The majority of studies included in this systematic review assessed the associations between basal cell carcinoma and smoking, alcohol or body mass index. However, more evidence is needed before conclusive recommendations can be formed regarding the relationship between cutaneous squamous cell carcinoma and alcohol or body mass index.

Autophagy Links Pattern Recognition Receptors to Tumor Cell Apoptosis

Pathogen nucleic acids are detected by the infected body’s immune cells via specific innate immune receptors, resulting in reactions such as secretion of T helper type 1 (Th1)-like and proinflammatory cytokines. Two studies have now reported the induction of cell death in melanoma cells, but not healthy skin cells, via stimulation of the cytoplasmic receptor MDA5 by the synthetic double-stranded RNA (dsRNA) agonist poly I:C, and one of the studies elucidated the mechanism for this response. Polyethyleneimine (PEI)-formulated poly I:C engages an intracellular process called autophagy via MDA5 to result in the induction of prodeath programs that ultimately lead to apoptosis of melanoma cells. Together with previous work, these reports demonstrate that immune detection of foreign nucleic acids involves diverse signaling pathways and thus yields different cellular outcomes that may overcome the inherent resistance of cancer cells to current cancer treatments.