Combined Anticancer Effect of Plasma-Activated Infusion and Salinomycin by Targeting Autophagy and Mitochondrial Morphology.

Non-thermal atmospheric pressure plasma (NTAPP)-activated liquids have emerged as new promising anticancer agents because they preferentially injure malignant cells. Here, we report plasma-activated infusion (PAI) as a novel NTAPP-based anti-neoplastic agent. PAI was prepared by irradiating helium NTAP to form a clinically approved infusion fluid. PAI dose-dependently killed malignant melanoma and osteosarcoma cell lines while showing much lower cytotoxic effects on dermal and lung fibroblasts. We found that PAI and salinomycin (Sal), an emerging anticancer stem cell agent, mutually operated as adjuvants. The combined administration of PAI and Sal was much more effective than single-agent application in reducing the growth and lung metastasis of osteosarcoma allografts with minimal adverse effects. Mechanistically, PAI explicitly induced necroptosis and increased the phosphorylation of receptor-interacting protein 1/3 rapidly and transiently. PAI also suppressed the ambient autophagic flux by activating the mammalian target of the rapamycin pathway. PAI increased the phosphorylation of Raptor, Rictor, and p70-S6 kinase, along with decreased LC3-I/II expression. In contrast, Sal promoted autophagy. Moreover, Sal exacerbated the mitochondrial network collapse caused by PAI, resulting in aberrant clustering of fragmented mitochondrial in a tumor-specific manner. Our findings suggest that combined administration of PAI and Sal is a promising approach for treating these apoptosis-resistant cancers.

Aspirin Induces Mitochondrial Ca2+ Remodeling in Tumor Cells via ROS‒Depolarization‒Voltage-Gated Ca2+ Entry.

Aspirin (acetylsalicylic acid) and its metabolite salicylate, have an anti-melanoma effect by evoking mitochondrial dysfunction through poorly understood mechanisms. Depolarization of the plasma membrane potential leads to voltage-gated Ca2+ entry (VGCE) and caspase-3 activation. In the present study, we investigated the role of depolarization and VGCE in aspirin's anti-melanoma effect. Aspirin and to a lesser extent, salicylate (≥2.5 mM) induced a rapid (within seconds) depolarization, while they caused comparable levels of depolarization with a lag of 2~4 h. Reactive oxygen species (ROS) generation also occurred in the two-time points, and antioxidants abolished the early ROS generation and depolarization. At the same concentrations, the two drugs induced apoptotic and necrotic cell death in a caspase-independent manner, and antioxidants and Ca2+ channel blockers prevented cell death. Besides ROS generation, reduced mitochondrial Ca2+ (Ca2+m) and mitochondrial membrane potential preceded cell death. Moreover, the cells expressed the Cav1.2 isoform of l-type Ca2+ channel, and knockdown of Cav1.2 abolished the decrease in Ca2+m. Our findings suggest that aspirin and salicylate induce Ca2+m remodeling, mitochondrial dysfunction, and cell death via ROS-dependent depolarization and VGCE activation.

The Mitochondrial Ca2+ Overload via Voltage-Gated Ca2+ Entry Contributes to an Anti-Melanoma Effect of Diallyl Trisulfide.

Allium vegetables such as garlic (Allium sativum L.) are rich in organosulfur compounds that prevent human chronic diseases, including cancer. Of these, diallyl trisulfide (DATS) exhibits anticancer effects against a variety of tumors, including malignant melanoma. Although previous studies have shown that DATS increases intracellular calcium (Ca2+) in different cancer cell types, the role of Ca2+ in the anticancer effect is obscure. In the present study, we investigated the Ca2+ pathways involved in the anti-melanoma effect. We used melittin, the bee venom that can activate a store-operated Ca2+ entry (SOCE) and apoptosis, as a reference. DATS increased apoptosis in human melanoma cell lines in a Ca2+-dependent manner. It also induced mitochondrial Ca2+ (Ca2+mit) overload through intracellular and extracellular Ca2+ fluxes independently of SOCE. Strikingly, acidification augmented Ca2+mit overload, and Ca2+ channel blockers reduced the effect more significantly under acidic pH conditions. On the contrary, acidification mitigated SOCE and Ca2+mit overload caused by melittin. Finally, Ca2+ channel blockers entirely inhibited the anti-melanoma effect of DATS. Our findings suggest that DATS explicitly evokes Ca2+mit overload via a non-SOCE, thereby displaying the anti-melanoma effect.

Autophagy inhibitors regulate TRAIL sensitivity in human malignant cells by targeting the mitochondrial network and calcium dynamics.

In a variety of cancer cell types, the pharmacological and genetic blockade of autophagy increases apoptosis induced by various anticancer drugs. These observations suggest that autophagy counteracts drug­induced apoptosis. We previously reported that in human melanoma and osteosarcoma cells, autophagy inhibitors, such as 3­methyladenine and chloroquine increased the sensitivity to apoptosis induced by tumor necrosis factor­related apoptosis­inducing ligand (TRAIL). In the present study, we report that different autophagy inhibitors regulate the mitochondrial network and calcium (Ca2+) dynamics in these cells. We found that compared to tumor cells, normal fibroblasts were more resistant to the cytotoxicity of TRAIL and autophagy inhibitors used either alone or in combination. Notably, TRAIL increased the autophagic flux in the tumor cells, but not in the fibroblasts. Live­cell imaging revealed that in tumor cells, TRAIL evoked modest mitochondrial fragmentation, while subtoxic concentrations of the autophagy inhibitors led to mitochondrial fusion. Co­treatment with TRAIL and subtoxic concentrations of the autophagy inhibitors resulted in severe mitochondrial fragmentation, swelling and clustering, similar to what was observed with autophagy inhibitors at toxic concentrations. The enhanced aberration of the mitochondrial network was preceded by a reduction in mitochondrial Ca2+ loading and store­operated Ca2+ entry. On the whole, the findings of this study indicate that co­treatment with TRAIL and autophagy inhibitors leads to increased mitochondrial Ca2+ and network dysfunction in a tumor­selective manner. Therefore, the co­administration of TRAIL and autophagy inhibitors may prove to be a promising tumor­targeting approach for the treatment of TRAIL­resistant cancer cells.

Cross-sectional survey on disease severity in Japanese patients with harlequin ichthyosis/ichthyosis: Syndromic forms and quality-of-life analysis in a subgroup.

BACKGROUND: Congenital ichthyoses (CIs) adversely affect quality of life (QOL) in patients. However, the effects of CIs on patient QOL have not been studied sufficiently. OBJECTIVE: To investigate the association between disease severity and QOL in patients with harlequin ichthyosis (HI) and ichthyosis: syndromic forms (ISFs) METHODS: Clinical information of patients with HI and ISFs from 2010 to 2015 were obtained from 100 dermatology departments/divisions of principal institutes/hospitals throughout Japan. We examined the relationship between disease severity and QOL in patients with HI and ISFs. Patients who were aged 8 years or older and participated in a multicenter retrospective questionnaire survey in Japan were assessed by dermatology life quality index (DLQI, range of 0-30) and clinical ichthyosis score (range of 0-100). RESULTS: Netherton syndrome patients had a significantly higher risk of allergy to food or environmental allergens than patients with other phenotypes. Keratitis-ichthyosis-deafness (KID) syndrome patients showed a significantly higher risk of skin infections than patients with other phenotypes. Complete data on DLQI were obtained from 13 patients, whose median age was 21 (8-71) years. Nine patients were male, and 4 were female. Systemic retinoids were administrated to 2 of the 3 HI patients. The Spearman's correlation coefficient between the clinical ichthyosis score and DLQI was 0.611 (P < 0.05). CONCLUSION: We confirmed that Netherton syndrome and KID syndrome patients have a higher risk of allergy to food or environmental allergens and of skin infections, respectively. QOL impairment correlates with disease severity in HI and ISFs patients.

Cold PSM, but not TRAIL, triggers autophagic cell death: A therapeutic advantage of PSM over TRAIL.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and cold plasma-stimulated medium (PSM) are promising novel anticancer tools due to their strong anticancer activities and high tumor-selectivity. The present study demonstrated that PSM and TRAIL may trigger autophagy in human malignant melanoma and osteosarcoma cells. Live-cell imaging revealed that even under nutritional and stress-free conditions, these cells possessed a substantial level of autophagosomes, which were localized in the cytoplasm separately from tubular mitochondria. In response to cytotoxic levels of PSM, the mitochondria became highly fragmented, and aggregated and colocalized with the autophagosomes. The cytotoxic effects of PSM were suppressed in response to various pharmacological autophagy inhibitors, including 3-methyladenine (3-MA) and bafilomycin A1, thus indicating the induction of autophagic cell death (ACD). Lethal levels of PSM also resulted in non-apoptotic, non-autophagic cell death in a reactive oxygen species-dependent manner under certain circumstances. Furthermore, TRAIL exhibited only a modest cytotoxicity toward these tumor cells, and did not induce ACD and mitochondrial aberration. The combined use of TRAIL and subtoxic concentrations of 3-MA resulted in decreased basal autophagy, increased mitochondrial aberration, colocalization with autophagosomes and apoptosis. These results indicated that PSM may induce ACD, whereas TRAIL may trigger cytoprotective autophagy that compromises apoptosis. To the best of our knowledge, the present study is the first to demonstrate that PSM can induce ACD in human cancer cells. These findings provide a rationale for the advantage of PSM over TRAIL in the destruction of apoptosis-resistant melanoma and osteosarcoma cells.

Plasma-stimulated medium kills TRAIL-resistant human malignant cells by promoting caspase-independent cell death via membrane potential and calcium dynamics modulation.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and cold plasma-stimulated medium (PSM) have been shown to exhibit tumor-selective cytotoxicity and have emerged as promising new tools for cancer treatment. However, to date, at least to the best of our knowledge, no data are available as to which substance is more potent in killing cancer cells. Thus, in this study, we systematically compared their abilities to kill human malignant cells from different origins. We found that PSM dose-dependently killed TRAIL-resistant melanoma, osteosarcoma and neuroblastoma cells. Moreover, PSM had little cytotoxicity toward osteoblasts. PSM was more potent than TRAIL in inducing caspase-3/7 activation, mitochondrial network aberration and caspase-independent cell death. We also found that PSM was more potent in inducing plasma membrane depolarization (PMD) and disrupting endoplasmic-mitochondrial Ca2+ homeostasis. Moreover, persistent PMD was caused by different membrane-depolarizing agents; the use of the anti-type II diabetes drug, glibenclamide, alone caused mitochondrial fragmentation and enhanced TRAIL-induced Ca2+ modulation, mitochondrial network abnormalities and caspase-independent cell killing. These results demonstrate that PSM has a therapeutic advantage over TRAIL owing to its greater capacity to evoke caspase-independent cell death via mitochondrial network aberration by disrupting membrane potential and Ca2+ homeostasis. These findings may provide a strong rationale for developing PSM as a novel approach for the treatment of TRAIL-resistant malignant cells.

Linear immunoglobulin A/G bullous dermatosis associated with ulcerative colitis.

Linear immunoglobulin (Ig)A/G bullous dermatosis (LAGBD) is an autoimmune bullous disease characterized by formation of subepidermal blisters and linear deposition of IgA and IgG antibodies along the basement membrane zone (BMZ). The association between linear IgA bullous dermatosis and ulcerative colitis (UC) is well recognized, but reports of UC-associated LAGBD are lacking. We have reported a 24-year-old man suffering from LAGBD associated with UC, which occurred before exacerbations of skin rash. A skin biopsy indicated a subepidermal blister with an infiltration of primarily neutrophils and eosinophils in the dermis. Direct immunofluorescence (IF) studies showed a linear deposition of IgA, IgG and C3c. Indirect IF of human skin revealed IgA and IgG anti-BMZ autoantibodies. Indirect IF of 1 M NaCl-split human skin demonstrated reactivity of IgA and IgG antibodies at the epidermal side. Immunoblotting showed that IgG antibodies reacted to the BP180 NC16a domain and 120-kDa linear IgA dermatosis-1, and enzyme-linked immunoassay detected IgG anti-BP230 antibodies. Administration of prednisolone and diaminodiphenyl sulfone (DDS) via the p.o. route improved skin lesions and bowel conditions. These results suggest that the bowel inflammation observed in UC may have a causative effect of initiation of the immune response to the skin and development of the bullous skin lesions in LAGBD. A combination of DDS and corticosteroid could be a recommended therapeutic option for patients with LAGBD with UC.

Dermoscopic features of small size pigmented basal cell carcinomas.

Dermoscopic images of histologically proven pigmented basal cell carcinomas (BCC) were retrospectively assessed to compare the dermoscopic features of BCC of 3 mm or less in diameter (n = 6) with BCC of 4-6 mm in diameter (n = 11). All lesions lacked the presence of a pigment network. BCC with a diameter of 3 mm or less had fewer positive dermoscopic features compared with the 4-6 mm in diameter BCC. Multiple blue-gray globules and large blue-gray ovoid nests were frequently present. Dermoscopy is a useful tool for early diagnosis of pigmented BCC, even when they are small.

Distinct effects of TRAIL on the mitochondrial network in human cancer cells and normal cells: role of plasma membrane depolarization.

Apo2 ligand/tumor necrosis factor-related apoptosis-inducing ligand (Apo2L/TRAIL) is a promising anticancer drug due to its tumor-selective cytotoxicity. Here we report that TRAIL exhibits distinct effects on the mitochondrial networks in malignant cells and normal cells. Live-cell imaging revealed that multiple human cancer cell lines and normal cells exhibited two different modes of mitochondrial responses in response to TRAIL and death receptor agonists. Mitochondria within tumor cells became fragmented into punctate and clustered in response to toxic stimuli. The mitochondrial fragmentation was observed at 4 h, then became more pronounced over time, and associated with apoptotic cell death. In contrast, mitochondria within normal cells such as melanocytes and fibroblasts became only modestly truncated, even when they were treated with toxic stimuli. Although TRAIL activated dynamin-related protein 1 (Drp1)-dependent mitochondrial fission, inhibition of this process by Drp1 knockdown or with the Drp1 inhibitor mdivi-1, potentiated TRAIL-induced apoptosis, mitochondrial fragmentation, and clustering. Moreover, mitochondrial reactive oxygen species (ROS)-mediated depolarization accelerated mitochondrial network abnormalities in tumor cells, but not in normal cells, and TRAIL caused higher levels of mitochondrial ROS accumulation and depolarization in malignant cells than in normal cells. Our findings suggest that tumor cells are more prone than normal cells to oxidative stress and depolarization, thereby being more vulnerable to mitochondrial network abnormalities and that this vulnerability may be relevant to the tumor-targeting killing by TRAIL.

Efficacy of additional i.v. immunoglobulin to steroid therapy in Stevens-Johnson syndrome and toxic epidermal necrolysis.

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare and life-threatening cutaneous adverse drug reactions. While there is no established therapy for SJS/TEN, systemic corticosteroids, plasma exchange and i.v. immunoglobulin (IVIG) have been used as treatment. The efficacy of IVIG is still controversial because total doses of IVIG used vary greatly from one study to another. The aim of this study was to evaluate the efficacy of IVIG, administrated for 5 days consecutively, in an open-label, multicenter, single-arm study in patients with SJS or TEN. IVIG (400 mg/kg per day) administrated for 5 days consecutively was performed as an additional therapy to systemic steroids in adult patients with SJS or TEN. Efficacy on day 7 of IVIG was evaluated. Parameters to assess clinical outcome were enanthema including ophthalmic and oral lesions, cutaneous lesions and general condition. These parameters were scored and recorded before and after IVIG. We enrolled five patients with SJS and three patients with TEN who did not respond sufficiently to systemic steroids before IVIG administration. All of the patients survived and the efficacy on day 7 of the IVIG was 87.5% (7/8 patients). Prompt amelioration was observed in skin lesions and enanthema in the patients in whom IVIG therapy was effective. Serious side-effects from the use of IVIG were not observed. IVIG (400 mg/kg per day) administrated for 5 days consecutively seems to be effective in patients with SJS or TEN. IVIG administrated together with steroids should be considered as a treatment modality for patients with refractory SJS/TEN. Further studies are needed to define the therapeutic efficacy of IVIG.

Adult-onset Satoyoshi syndrome with prominent laterality of clinical features.

We herein report the case of a patient with adult-onset Satoyoshi syndrome. Alopecia was detected on the patient's head, left leg and abdomen, with pigmentation on the left thigh and abdomen. Painful muscle spasms were also noted in the abdomen and left upper and lower extremities, and a sensory disturbance was present in the left thigh. A skin biopsy of this field showed lymphocyte infiltration, and the patient was found to be positive for antinuclear antibodies and rheumatoid factor. These clinical findings were atypical, as they were lateralized. This case is the first report of Satoyoshi syndrome associated with a sensory disturbance. The patient's histological findings and positivity for autoantibodies indicated the presence of immunological abnormalities in this case of Satoyoshi syndrome.

Mitochondrial division inhibitor-1 induces mitochondrial hyperfusion and sensitizes human cancer cells to TRAIL-induced apoptosis.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising candidate for cancer treatment, but some cancer cell types are resistant to TRAIL cytotoxicity. Therefore, overcoming this resistance is necessary for effective TRAIL therapy. Mitochondrial morphology is important for the maintenance of cell function and survival, and is regulated by the delicate balance between fission and fusion. However, the role of mitochondrial morphology dynamics in TRAIL-induced apoptosis is unknown. Here we show that mitochondrial division inhibitor-1 (mdivi-1), an inhibitor of dynamin-related protein1 (Drp1), modulates mitochondrial morphology and TRAIL-induced apoptosis in human cancer cells. mdivi-1 treatment (≥12.5 µM) caused dose- and time­dependent cell death in malignant melanoma, lung cancer and osteosarcoma cells, while sparing normal cells. mdivi-1 also sensitized cancer cells to TRAIL-induced apoptosis. This potentiation of apoptosis occurred through a caspase-depependent mechanism including the mitochondrial and endoplasmic reticulum (ER) stress pathways. Mdivi-1 potentiated mitochondrial oxidative stress, a major cause of mitochondrial and ER stresses, as evidenced by increases in mitochondrial reactive oxygen species levels, mitochondrial mass, and cardiolipin oxidation. Live cell fluorescence imaging using MitoTracker Red CMXRos revealed that Mdivi-1 caused substantial mitochondrial hyperfusion. Moreover, silencing of Drp1 expression also caused mitochondrial hyperfusion and sensitized cancer cells to TRAIL-induced apoptosis. Our results suggest that cancer cells are more vulnerable than normal cells to a perturbation in mitochondrial morphology dynamics and that this higher susceptibility can be exploited to selectively kill cancer cells and sensitize to TRAIL.

Depolarization Controls TRAIL-Sensitization and Tumor-Selective Killing of Cancer Cells: Crosstalk with ROS.

Conventional genotoxic anti-cancer drugs target the proliferative advantage of tumor cells over normal cells. This kind of approach lacks the selectivity of treatment to cancer cells, because most of the targeted pathways are essential for the survival of normal cells. As a result, traditional cancer treatments are often limited by undesirable damage to normal cells (side-effects). Ideal anti-cancer drugs are expected to be highly effective against malignant tumor cells with minimal cytotoxicity toward normal cells. Such selective killing can be achieved by targeting pathways essential for the survival of cancer cells, but not normal cells. As cancer cells are characterized by their resistance to apoptosis, selective apoptosis induction is a promising approach for selective killing of cancer cells. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising tumor-selective anti-cancer drug. However, the congenital and acquired resistance of some cancer cell types, including malignant melanoma cells, currently impedes effective TRAIL therapy, and an innovative approach that can override TRAIL resistance is urgently required. Apoptosis is characterized by cell shrinkage caused by disruption of the maintenance of the normal physiological concentrations of K(+) and Na(+) and intracellular ion homeostasis. The disrupted ion homeostasis leads to depolarization and apoptosis. Recent evidence suggests that depolarization is an early and prerequisite event during TRAIL-induced apoptosis. Moreover, diverse natural products and synthetic chemicals capable of depolarizing the cell membrane exhibit tumor-selective killing and TRAIL-sensitizing effects. Here, we discuss the role of depolarization in selective killing of cancer cells in connection with the emerging concept that oxidative stress is a critical mediator of mitochondrial and endoplasmic reticulum dysfunctions and serves as a tumor-selective target in cancer treatment.

Crosstalk between mitochondrial ROS and depolarization in the potentiation of TRAIL-induced apoptosis in human tumor cells.

We previously showed that membrane-depolarizing agents such as K+ and ATP-sensitive potassium (KATP) channel inhibitors potentiate tumor necrosis factor-related apoptosis­inducing ligand (TRAIL)-induced apoptosis in human melanoma cells, but not in normal melanocytes. In this study, we investigated whether the tumor-selective effect of depolarization was observed among different tumor cell types and the mechanisms by which depolarization potentiates death pathways. We found that K+ and KATP channel inhibitors elicited similar apoptosis-potentiating effects in human tumor cells with different origins, including leukemia, melanoma and lung cancer cells. In contrast, minimal potentiation of apoptosis was observed in non-transformed lung cells. The potentiation was associated with increased mitochondrial and endoplasmic reticulum stress death pathways. Upregulation of surface TRAIL receptor-2 expression and modulation of the caspase-3 activation pathway seemed to play roles in the enhancement of death signaling. Moreover, the results showed that depolarization and mitochondria­derived reactive oxygen species (mROS) mutually regulated one another. Depolarization potentiated TRAIL-induced mROS accumulation. Conversely, scavenging of mROS by the antioxidant MnTBaP reduced depolarization, whereas mROS accumulation caused by metabolic inhibitors potentiated the depolarization. These findings suggest a positive loop between depolarization and mROS accumulation. This may provide a rationale for the tumor-selective cytotoxicity and/or potentiation of TRAIL cytotoxicity of a wide variety of ROS-producing substances in different types of tumor cells.