Differential effects of 5-aminolaevulinic acid photodynamic therapy and psoralen + ultraviolet A therapy on p53 phosphorylation in normal human skin in vivo

Hesperidin exhibits in vitro and in vivo antitumor effects in human osteosarcoma MG-63 cells and xenograft mice models via inhibition of cell migration and invasion, cell cycle arrest and induction of mitochondrial-mediated apoptosis

The objective of the present study was to investigate the anticancer properties of hesperidin against human osteosarcoma MG-63 cells. Its effects on apoptosis, cell migration, cell invasion and cell cycle arrest, and its effects on tumor volume and weight were also evaluated in the present study. MTS assay was used to study the cytotoxic effects of the compound on cell viability. Effects on apoptosis and cell cycle arrest were evaluated by flow cytometry. In vitro wound healing assay and Matrigel assay were performed to study the effects of hesperidin on cell migration and cell invasion, respectively. Hesperidin exerted dose-dependent and time-dependent growth inhibitory effects on cervical cancer cells with IC50 values of 33.5, 23.8 and 17.6 µM, respectively, at 24, 48 and 72 h time intervals. Hesperidin led to early and late apoptosis induction in these cells. Hesperidin-treated cells also led to G2/M phase cell cycle arrest, which exhibited strong dose-dependence. Hesperidin treatment also led to inhibition of cell migration and invasion.

Polyphyllin G induce apoptosis and autophagy in human nasopharyngeal cancer cells by modulation of AKT and mitogen-activated protein kinase pathways in vitro and in vivo

Polyphyllin G (also call polyphyllin VII), extract from rhizomes of Paris yunnanensis Franch, has been demonstrated to have strong anticancer activities in a wide variety of human cancer cell lines. Previous studies found that Polyphyllin G induced apoptotic cell death in human hepatoblastoma cancer and lung cancer cells. However, the underlying mechanisms of autophagy in human nasopharyngeal carcinoma (NPC) remain unclear. In this study, Polyphyllin G can potently induced apoptosis dependent on the activations of caspase-8, -3, and -9 and the changes of Bcl-2, Bcl-xL and Bax protein expression in different human NPC cell lines (HONE-1 and NPC-039). The amount of both LC3-II and Beclin-1 was intriguingly increased suggest that autophagy was induced in Polyphyllin G-treated NPC cells. To further clarify whether Polyphyllin G-induced apoptosis and autophagy depended on AKT/ERK/JNK/p38 MAPK signaling pathways, cells were combined treated with AKT inhibitor (LY294002), ERK1/2 inhibitor (U0126), p38 MAPK inhibitor (SB203580), or JNK inhibitor (SP600125). These results demonstrated that Polyphyllin G induced apoptosis in NPC cells through activation of ERK, while AKT, p38 MAPK and JNK were responsible for Polyphyllin G-induced autophagy. Finally, an administration of Polyphyllin G effectively suppressed the tumor growth in the NPC carcinoma xenograft model in vivo. In conclusion, our results reveal that Polyphyllin G inhibits cell viability and induces apoptosis and autophagy in NPC cancer cells, suggesting that Polyphyllin G is an attractive candidate for tumor therapies. Polyphyllin G may promise candidate for development of antitumor drugs targeting nasopharyngeal carcinoma.

Photodynamic Therapy: A Clinical Consensus Guide

BACKGROUND

The American Society of Dermatologic Surgery (ASDS) periodically develops consensus documents for its members concerning various aspects of dermatologic surgery. Advances in photodynamic therapy (PDT) have been many and PDT use has been established in a variety of skin conditions.

OBJECTIVE

The ASDS board of directors proposed a committee of experts in the field to develop consensus documents on different treatments. An expert panel reviewed the literature on PDT and discussed the findings. The consensus was reached with evidence-based recommendations on different clinical applications for PDT.

PATIENTS AND METHODS

This consensus document includes discussions regarding PDT, including different photosensitizers and various light source activators, historical perspective, mechanism of action, various therapeutic indications and expected outcomes, pre- and post-care, and management of adverse outcomes.

RESULTS

Photodynamic therapy is highly effective for pre-cancerous lesions, superficial nonmelanoma skin cancers, inflammatory acne vulgaris and other conditions. New protocols including laser mediated PDT significantly improve results for several indications.

CONCLUSION

The ASDS consensus document on PDT will be helpful for educating members on safe and effective PDT for a variety of indications.

Dehydroandrographolide, an iNOS inhibitor, extracted from Andrographis paniculata (Burm.f.) Nees, induces autophagy in human oral cancer cells

Autophagy, which is constitutively executed at the basal level in all cells, promotes cellular homeostasis by regulating the turnover of organelles and proteins. Andrographolide and dehydroandrographolide (DA) are the two principle components of Andrographis paniculata (Burm.f.) Nees. and are the main contributors to its therapeutic properties. However, the pharmacological activities of dehydroandrographolide (DA) remain unclear. In this study, DA induces oral cancer cell death by activating autophagy. Treatment with autophagy inhibitors inhibited DA-induced human oral cancer cell death. In addition, DA increased LC3-II expression and reduced p53 expression in a time- and concentration-dependent manner. Furthermore, DA induced autophagy and decreased cell viability through modulation of p53 expression. DA-induced autophagy was triggered by an activation of JNK1/2 and an inhibition of Akt and p38. In conclusion, this study demonstrated that DA induced autophagy in human oral cancer cells by modulating p53 expression, activating JNK1/2, and inhibiting Akt and p38. Finally, an administration of DA effectively suppressed the tumor formation in the oral carcinoma xenograft model in vivo. This is the first study to reveal the novel function of DA in activating autophagy, suggesting that DA could serve as a new and potential chemopreventive agent for treating human oral cancer.

Selective Hyaluronan-CD44 Signaling Promotes miRNA-21 Expression and Interacts with Vitamin D Function during Cutaneous Squamous Cell Carcinomas Progression Following UV Irradiation

Hyaluronan (HA), the major extracellular matrix component, is often anchored to CD44, a family of structurally/functionally important cell surface receptors. Recent results indicate that UV irradiation (UVR)-induced cutaneous squamous cell carcinomas (SCC) overexpress a variety of CD44 variant isoforms (CD44v), with different CD44v isoforms appear to confer malignant SCC properties. UVR also stimulates HA degradation in epidermal keratinocytes. Both large HA polymers and their UVR-induced catabolic products (small HA) selectively activate CD44-mediated cellular signaling in normal keratinocytes and SCC cells, with all of the downstream processes being mediated by RhoGTPases (e.g., Rac1 and Rho). Importantly, we found that the hormonally active form of vitamin D 1,25(OH)2D3 not only prevents the UVR-induced small HA activation of abnormal keratinocyte behavior and SCC progression, but also enhances large HA stimulation of normal keratinocyte activities and epidermal function(s). The aim of this hypothesis and theory article is to question whether matrix HA and its UVR-induced catabolic products (e.g., large and small HA) can selectively activate CD44-mediated cellular signaling such as GTPase (Rac and RhA) activation. We suggested that large HA-CD44 interaction promotes Rac-signaling and normal keratinocyte differentiation (lipid synthesis), DNA repair, and keratinocyte survival function. Conversely, small HA-CD44 interaction stimulates RhoA activation, NFκB/Stat-3 signaling, and miR-21 production, resulting in inflammation and proliferation as well as SCC progression. We also question whether vitamin D treatment displays any effect on small HA-CD44v-mediated RhoA signaling, inflammation, and SCC progression, as well as large HA-CD44-mediated differentiation, DNA repair, keratinocyte survival, and normal keratinocyte function. In addition, we discussed that the topical application of signaling perturbation agents (e.g., Y27623, a ROK inhibitor) may be used to treat certain skin diseases displaying upregulation of keratinocyte proliferation such as psoriasis and actinic keratoses in order to correct the imbalance between Rac and RhoA signaling during various UV irradiation-induced skin diseases in patients. Finally, we proposed that matrix HA/CD44-signaling strategies and matrix HA (HAS vs. HAL or HAS → HAL)-based therapeutic approaches (together with vitamin D) may be used for the treatment of patients suffering a number of UV irradiation-induced skin diseases (e.g., inflammation, skin cancer, and chronic non-healing wounds).

Pterostilbene induce autophagy on human oral cancer cells through modulation of Akt and mitogen-activated protein kinase pathway

OBJECTIVES

Extensive research supports the administration of herbal medicines or natural foods during cancer therapy. Pterostilbene, a naturally occurring phytoalexin, has various pharmacological activities, including antioxidant activity, cancer prevention activity, and cytotoxicity to many cancers. However, the effect of pterostilbene on the autophagy of tumor cells has not been clarified.

MATERIALS AND METHODS

In this study, the unique effects of pterostilbene on the autophagy of human oral cancer cells were investigated.

RESULTS

The results of this study showed that pterostilbene effectively inhibited the growth of human oral cancer cells by inducing cell cycle arrest and apoptosis. In addition, the formation of acidic vesicular organelles and LC3-II production also demonstrated that pterostilbene induced autophagy. Administering 3-methylamphetamine (3-MA) and bafilomycin A1 (BafA1) exerted differing effects on the pterostilbene-induced death of human oral cancer cells. Pterostilbene-induced autophagy was triggered by activation of JNK1/2 and inhibition of Akt, ERK1/2, and p38.

CONCLUSION

In conclusion, this study demonstrated that pterostilbene caused autophagy and apoptosis in human oral cancer cells, suggesting that pterostilbene could serve as a new and promising agent for treating human oral cancer.

Psoralen reverses docetaxel-induced multidrug resistance in A549/D16 human lung cancer cells lines

Chemotherapy is the recommended treatment for advanced-stage cancers. However, the emergence of multidrug resistance (MDR), the ability of cancer cells to become simultaneously resistant to different drugs, limits the efficacy of chemotherapy. Previous studies have shown that herbal medicine or natural food may be feasible for various cancers as potent chemopreventive drug. This study aims to explore the capablility of reversing the multidrug resistance of docetaxel (DOC)-resistant A549 cells (A549/D16) of psoralen and the underlying mechanisms. In this study, results showed that the cell viability of A549/D16 subline is decreased when treated with psoralen plus DOC, while psoralen has no effect on the cell proliferation on A549 and A549/D16 cells. Furthermore, mRNA and proteins levels of ABCB1 were decreased in the presence of psoralen, while decreased ABCB1 activity was also revealed by flow cytometry. Based on these results, we believe that psoralen may be feasible for reversing the multidrug resistance by inhibiting ABCB1 gene and protein expression. Such inhibition will lead to a decrease in ABCB1 activity and anti-cancer drug efflux, which eventually result in drug resistance reversal and therefore, sensitizing drug-resistant cells to death in combination with chemotherapeutic drugs.

Facial basal cell carcinomas recurring after photodynamic therapy: a retrospective analysis of histological subtypes

BACKGROUND

Photodynamic therapy (PDT) is an established treatment for basal cell carcinomas (BCCs). Although recurrences are sometime observed, their histological patterns have never been specifically studied or compared with the one of the initial tumor.

OBJECTIVE

To compare the histopathological aggressiveness of BCCs recurring after PDT with that of the primary tumors.

METHODS

The study population included 12 patients with 16 post PDT recurrent BCCs. Outcome measures were proportion of histologically aggressive subtypes in BCC recurrences vs. primary tumor.

RESULTS

62.5% of recurrent BCCs displayed a transition from a non-aggressive to an aggressive subtype.

CONCLUSIONS

Post PDT recurrences appear to display an increased histological aggressiveness, although the latter may reflect the natural course of tumor progression. Despite the presence of potential biases, our study raises the possibility that PDT favors the selection of more aggressive tumor cells. Better systematic large-scale follow-up studies are required to assess the exact frequency and histological types of BCC recurrences after PDT.

Guidelines for topical photodynamic therapy: update

Multicentre randomized controlled studies now demonstrate high efficacy of topical photodynamic therapy (PDT) for actinic keratoses, Bowen's disease (BD) and superficial basal cell carcinoma (BCC), and efficacy in thin nodular BCC, while confirming the superiority of cosmetic outcome over standard therapies. Long-term follow-up studies are also now available, indicating that PDT has recurrence rates equivalent to other standard therapies in BD and superficial BCC, but with lower sustained efficacy than surgery in nodular BCC. In contrast, current evidence does not support the use of topical PDT for squamous cell carcinoma. PDT can reduce the number of new lesions developing in patients at high risk of skin cancer and may have a role as a preventive therapy. Case reports and small series attest to the potential of PDT in a wide range of inflammatory/infective dermatoses, although recent studies indicate insufficient evidence to support its use in psoriasis. There is an accumulating evidence base for the use of PDT in acne, while detailed study of an optimized protocol is still required. In addition to high-quality treatment site cosmesis, several studies observe improvements in aspects of photoageing. Management of treatment-related pain/discomfort is a challenge in a minority of patients, and the modality is otherwise well tolerated. Long-term studies provide reassurance over the safety of repeated use of PDT.

Central role of mitochondria and p53 in PUVA-induced apoptosis in human keratinocytes cell line NCTC-2544

Despite strong evidence concerning the high efficiency of PUVA therapy (psoralen plus UVA light), its mechanism of action has not yet been fully elucidated. In this study, we have evaluated in a cell line of human keratinocytes (NCTC-2544) the effects of two linear psoralen derivatives, 8-methoxypsoralen (8-MOP) and 5-methoxypsoralen (5-MOP), that are widely used in PUVA therapy and two angular derivatives, Angelicin (ANG) and 4,6,4'-trymetyl angelicin (TMA). All derivatives photoinduce cellular death, TMA being the most active compound. The cell cycle analysis showed that the four derivatives induce, 24 h after irradiation, a cell cycle arrest in G1 phase later followed by massive apoptosis. The G1 arrest is correlated to an increase in the expression of p21(Waf1/Cip1), a protein associated with the cell cycle block and apoptosis. Furthermore, treatment of NCTC-2544 resulted in p53 activation by 5-MOP, 8-MOP, and ANG but not TMA and its phosphorylation at serine-15. The levels of p21(Waf1/Cip1) paralleled p53 protein staining pattern suggesting that p53 activation correlated with p21(Waf1/Cip1) induction. Simultaneous to p53 activation, psoralens induced mitochondrial depolarization, cytochrome c release, mitochondrial production of reactive oxygen species, as well as caspase-3 and -9 activation. Thus these results strongly indicate the necessity of p53 activation and the induction of the apoptotic machinery downstream of mitochondria.