Superior Drug Delivery Performance of Multifunctional Bilosomes: Innovative Strategy to Kill Skin Cancer Cells for Nanomedicine Application.

Purpose: Numerous failures in melanoma treatment as a highly aggressive form of skin cancer with an unfavorable prognosis and excessive resistance to conventional therapies are prompting an urgent search for more effective therapeutic tools. Consequently, to increase the treatment efficiency and to reduce the side effects of traditional administration ways, herein, it has become crucial to combine photodynamic therapy as a promising therapeutic approach with the selectivity and biocompatibility of a novel colloidal transdermal nanoplatform for effective delivery of hybrid cargo with synergistic effects on melanoma cells. Methods: The self-assembled bilosomes, co-stabilized with L-α-phosphatidylcholine, sodium cholate, Pluronic® P123, and cholesterol, were designated, and the stability of colloidal vesicles was studied using dynamic and electrophoretic light scattering, also provided in cell culture medium (Dulbecco's Modified Eagle's Medium). The hybrid compounds - a classical photosensitizer (Methylene Blue) along with a complementary natural polyphenolic agent (curcumin), were successfully co-loaded, as confirmed by UV-Vis, ATR-FTIR, and fluorescent spectroscopies. The biocompatibility and usefulness of the polymer functionalized bilosome with loaded double cargo were demonstrated in vitro cyto- and phototoxicity experiments using normal keratinocytes and melanoma cancer cells. Results: The in vitro bioimaging and immunofluorescence study upon human skin epithelial (A375) and malignant (Me45) melanoma cell lines established the protective effect of the PEGylated bilosome surface. This effect was confirmed in cytotoxicity experiments, also determined on human cutaneous (HaCaT) keratinocytes. The flow cytometry experiments indicated the enhanced uptake of the encapsulated hybrid cargo compared to the non-loaded MB and CUR molecules, as well as a selectivity of the obtained nanocarriers upon tumor cell lines. The phyto-photodynamic action provided 24h-post irradiation revealed a more significant influence of the nanoplatform on Me45 cells in contrast to the A375 cell line, causing the cell viability rate below 20% of the control. Conclusion: As a result, we established an innovative and effective strategy for potential metastatic melanoma treatment through the synergism of phyto-photodynamic therapy and novel bilosomal-origin nanophotosensitizers.

The anticancer impacts of free and liposomal caffeic acid phenethyl ester (CAPE) on melanoma cell line (A375).

The deadliest type of skin cancer, malignant melanoma, is also the reason for the majority of skin cancer-related deaths. The objective of this article was to investigate the efficiency of free caffeic acid phenethyl ester (CAPE) and liposomal CAPE in inducing apoptosis in melanoma cells (A375) in in vitro. CAPE was loaded into liposomes made up of hydrogenated soybean phosphatidylcholine, cholesterol, and 1,2-distearoyl-sn-glycero-3 phosphoethanolamine-N-[methoxy (polyethylene glycol)-2000], and their physicochemical properties were assessed. (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) test was performed for comparing the cytotoxicity of free CAPE and liposomal CAPE at dosages of 10, 15, 25, 50, 75 and the highest dose of 100 µg/mL for period of 24 and 48 h on A375 cell line to calculate IC50. Apoptosis and necrosis were evaluated in A375 melanoma cancer cells using flow cytometry. Atomic force microscopy was utilized to determine the nanomechanical attributes of the membrane structure of A375 cells. To determine whether there were any effects on apoptosis, the expression of PI3K/AKT1 and BAX/BCL2 genes was analyzed using the real-time polymerase chain reaction technique. According to our results, the maximum amount of drug release from nanoliposomes was determined to be 91% and the encapsulation efficiency of CAPE in liposomes was 85.24%. Also, the release of free CAPE was assessed to be 97%. Compared with liposomal CAPE, free CAPE showed a greater effect on reducing the cancer cell survival after 24 and 48 h. Therefore, IC50 values of A375 cells treated with free and liposomal CAPE were calculated as 47.34 and 63.39 µg/mL for 24 h. After 48 h of incubation of A375 cells with free and liposomal CAPE, IC50 values were determined as 30.55 and 44.83 µg/mL, respectively. The flow cytometry analysis revealed that the apoptosis induced in A375 cancer cells was greater when treated with free CAPE than when treated with liposomal CAPE. The highest nanomechanical changes in the amount of cell adhesion forces, and elastic modulus value were seen in free CAPE. Subsequently, the greatest decrease in PI3K/AKT1 gene expression ratio occurred in free CAPE.

[Effect of acetylalkannin from Arnebia euchroma on proliferation, migration, and invasion of human melanoma A375 cells].

This study aimed to explore the effect and mechanism of acetylalkannin from Arnebia euchroma on the proliferation, migration, and invasion of human melanoma A375 cells. A375 cells were divided into a blank group, and low-, medium-, and high-dose acetylalkannin groups(0.5, 1.0, and 2.0 µmol·L~(-1)). The MTT assay was used to detect cell proliferation. Cell scratch and transwell migration assays were used to detect cell migration ability, and the transwell invasion assay was used to detect cell invasion ability. Western blot was used to detect the protein expression of migration and invasion-related N-cadherin, vimentin, matrix metalloproteina-se-9(MMP-9), and Wnt/ß-catenin pathway-related Wnt1, Axin2, glycogen synthase kinase-3ß(GSK-3ß), phosphorylated GSK-3ß(p-GSK-3ß), ß-catenin, cell cycle protein D_1(cyclin D_1), and p21. Real-time fluorescence-based quantitative polymerase chain reaction(real-time PCR) was used to detect the mRNA expression of E-cadherin, matrix metalloproteinase-2(MMP-2), N-cadherin, vimentin, ß-catenin, snail-1, and CD44. MTT results showed that the cell inhibition rates in the acetylalkannin groups significantly increased as compared with that in the blank group(P<0.01). The results of cell scratch and transwell assays showed that compared with the blank group, the acetylalkannin groups showed reduced cell migration and invasion, and migration and invasion rates(P<0.05, P<0.01) and weakened horizontal and vertical migration and invasion abilities. Western blot results showed that compared with the blank group, the high-dose acetylalkannin group showed increased expression of Axin2 protein(P<0.05), and decreased expression of N-cadherin, vimentin, MMP-9, Wnt1, p-GSK-3ß, ß-catenin, cyclin D_1, and p21 proteins(P<0.05, P<0.01). The expression of GSK-3ß protein did not change significantly. PCR results showed that the overall trend of MMP-2, N-cadherin, vimentin, ß-catenin, snail-1, and CD44 mRNA expression was down-regulated(P<0.01), and the expression of E-cadherin mRNA increased(P<0.01). Acetylalkannin can inhibit the proliferation, migration, and invasion of human melanoma A375 cells, and its mechanism of action may be related to the regulation of Wnt/ß-catenin signaling pathway.

Effects of folate on telomere length and chromosome stability of human fibroblasts and melanoma cells in vitro: a comparison of folic acid and 5-methyltetrahydrofolate.

Telomere length (TL), which is maintained by human telomerase reverse transcriptase (hTERT; component of telomerase) and/or TRF1/TRF2 (core components of shelterin) via different mechanisms, is essential for chromosomal stability and cell survival. Folates comprise a group of essential B9 vitamin that involve in DNA synthesis and methylation. This study aimed to evaluate the effects of folic acid (FA) and 5-methyltetrahydrofolate (5-MeTHF) on TL, chromosome stability, and cell survival of telomerase-negative BJ and telomerase-positive A375 cells in vitro. BJ and A375 cells were cultured in modified medium with FA or 5-MeTHF (22.6 or 2260 nM) for 28 days. TL and mRNA expression were determined by RT-qPCR. Chromosome instability (CIN) and cell death were measured by CBMN-Cyt assay. Results showed that abnormal TL elongation was observed in FA- and 5-MeTHF-deficient BJ cells. The TL of A375 cells showed no obvious alterations under the FA-deficient condition but was significantly elongated under the 5-MeTHF-deficient condition. In both BJ and A375 cells, FA and 5-MeTHF deficiency caused decreased TRF1, TRF2, and hTERT expression, increased CIN and cell death; while a high concentration of 5-MeTHF induced elongated TL, elevated CIN, increased TRF1 and TRF2 expression, and decreased hTERT expression, when compared with the FA counterpart. These findings concluded that folate deficiency induced TL instability in both telomerase-negative and -positive cells, and FA was more efficient in maintaining TL and chromosome stability compared with 5-MeTHF.

Effects of folate on telomere length and chromosome stability of human fibroblasts and melanoma cells in vitro: a comparison of folic acid and 5-methyltetrahydrofolate.

Telomere length (TL), which is maintained by human telomerase reverse transcriptase (hTERT; component of telomerase) and/or TRF1/TRF2 (core components of shelterin) via different mechanisms, is essential for chromosomal stability and cell survival. Folates comprise a group of essential B9 vitamin that involve in DNA synthesis and methylation. This study aimed to evaluate the effects of folic acid (FA) and 5-methyltetrahydrofolate (5-MeTHF) on TL, chromosome stability, and cell survival of telomerase-negative BJ and telomerase-positive A375 cells in vitro. BJ and A375 cells were cultured in modified medium with FA or 5-MeTHF (22.6 or 2260 nM) for 28 days. TL and mRNA expression were determined by RT-qPCR. Chromosome instability (CIN) and cell death were measured by CBMN-Cyt assay. Results showed that abnormal TL elongation was observed in FA and 5-MeTHF deficient BJ cells. The TL of A375 cells showed no obvious alterations under the FA-deficient condition but was significantly elongated under the 5-MeTHF-deficient condition. In both BJ and A375 cells, FA and 5-MeTHF deficiency caused decreased TRF1, TRF2, and hTERT expression, increased CIN and cell death; while a high concentration of 5-MeTHF induced elongated TL, elevated CIN, increased TRF1 and TRF2 expression and decreased hTERT expression, when compared with the FA counterpart. These findings concluded that folate deficiency induced TL instability in both telomerase-negative and -positive cells, and FA was more efficient in maintaining TL and chromosome stability compared with 5-MeTHF.

The Alternative TrkAIII Splice Variant, a Targetable Oncogenic Participant in Human Cutaneous Malignant Melanoma.

Post-therapeutic relapse, poor survival rates and increasing incidence justify the search for novel therapeutic targets and strategies in cutaneous malignant melanoma (CMM). Within this context, a potential oncogenic role for TrkA in CMM is suggested by reports of NTRK1 amplification, enhanced TrkA expression and intracellular TrkA activation associated with poor prognosis. TrkA, however, exhibits tumour-suppressing properties in melanoma cell lines and has recently been reported not to be associated with CMM progression. To better understand these contradictions, we present the first analysis of potential oncogenic alternative TrkA mRNA splicing, associated with TrkA immunoreactivity, in CMMs, and compare the behaviour of fully spliced TrkA and the alternative TrkAIII splice variant in BRAF(V600E)-mutated A375 melanoma cells. Alternative TrkA splicing in CMMs was associated with unfolded protein response (UPR) activation. Of the several alternative TrkA mRNA splice variants detected, TrkAIII was the only variant with an open reading frame and, therefore, oncogenic potential. TrkAIII expression was more frequent in metastatic CMMs, predominated over fully spliced TrkA mRNA expression in ≈50% and was invariably linked to intracellular phosphorylated TrkA immunoreactivity. Phosphorylated TrkA species resembling TrkAIII were also detected in metastatic CMM extracts. In A375 cells, reductive stress induced UPR activation and promoted TrkAIII expression and, in transient transfectants, promoted TrkAIII and Akt phosphorylation, enhancing resistance to reductive stress-induced death, which was prevented by lestaurtinib and entrectinib. In contrast, fully spliced TrkA was dysfunctional in A375 cells. The data identify fully spliced TrkA dysfunction as a novel mechanism for reducing melanoma suppression, support a causal relationship between reductive stress, UPR activation, alternative TrkAIII splicing and TrkAIII activation and characterise a targetable oncogenic pro-survival role for TrkAIII in CMM.

Effect of acetylalkannin from Arnebia euchroma on proliferation, migration, and invasion of human melanoma A375 cells / 中国中药杂志

This study aimed to explore the effect and mechanism of acetylalkannin from Arnebia euchroma on the proliferation, migration, and invasion of human melanoma A375 cells. A375 cells were divided into a blank group, and low-, medium-, and high-dose acetylalkannin groups(0.5, 1.0, and 2.0 μmol·L~(-1)). The MTT assay was used to detect cell proliferation. Cell scratch and transwell migration assays were used to detect cell migration ability, and the transwell invasion assay was used to detect cell invasion ability. Western blot was used to detect the protein expression of migration and invasion-related N-cadherin, vimentin, matrix metalloproteina-se-9(MMP-9), and Wnt/β-catenin pathway-related Wnt1, Axin2, glycogen synthase kinase-3β(GSK-3β), phosphorylated GSK-3β(p-GSK-3β), β-catenin, cell cycle protein D_1(cyclin D_1), and p21. Real-time fluorescence-based quantitative polymerase chain reaction(real-time PCR) was used to detect the mRNA expression of E-cadherin, matrix metalloproteinase-2(MMP-2), N-cadherin, vimentin, β-catenin, snail-1, and CD44. MTT results showed that the cell inhibition rates in the acetylalkannin groups significantly increased as compared with that in the blank group(P<0.01). The results of cell scratch and transwell assays showed that compared with the blank group, the acetylalkannin groups showed reduced cell migration and invasion, and migration and invasion rates(P<0.05, P<0.01) and weakened horizontal and vertical migration and invasion abilities. Western blot results showed that compared with the blank group, the high-dose acetylalkannin group showed increased expression of Axin2 protein(P<0.05), and decreased expression of N-cadherin, vimentin, MMP-9, Wnt1, p-GSK-3β, β-catenin, cyclin D_1, and p21 proteins(P<0.05, P<0.01). The expression of GSK-3β protein did not change significantly. PCR results showed that the overall trend of MMP-2, N-cadherin, vimentin, β-catenin, snail-1, and CD44 mRNA expression was down-regulated(P<0.01), and the expression of E-cadherin mRNA increased(P<0.01). Acetylalkannin can inhibit the proliferation, migration, and invasion of human melanoma A375 cells, and its mechanism of action may be related to the regulation of Wnt/β-catenin signaling pathway.

Antioxidant and cytotoxic potentials of the methanolic extract of Teucrium persicum Boiss. in A-375 melanoma cells.

Objective: Teucrium persicum is an Iranian endemic plant used in Iranian traditional medicine. Materials and Methods: The total phenolic and total flavonoid contents, and antioxidant potential of the methanolic extract of T. persicum were determined. The MTT test was used to evaluate the inhibitory effect of the extract on the viability of A-375 cells. The clonogenic, micronucleus formation, and acridine orange/ethidium bromide staining methods were used to evaluate the survival and proliferation of A-375 cells. Apoptosis was evaluated by using DNA fragmentation assay and measuring the activity of caspase 3/7. To study the effect of the extract on the migration of A-375 cells, the in vitro wound-healing (scratch) assay was employed. Results: The average total phenolic and flavonoid contents and antioxidant properties of the extract were 6.97±0.011 mg Ellagic acid (EGA)/g, 46.83±0.0019 mg of the ethoxyquin (1,2-dihydro-6-ethoxy-2,2,4-trimethylquinoline; EQ)/g of dried extract, and 10±0.002 µg/ml, respectively. The IC50 value of the T. persicum methanolic extract was 13 µg/ml for 48 hr. The DNA fragmentation pattern and the activity of caspase3/7 suggested that the reduction of the cell viability may be due to apoptosis induction. Microscopic observations showed nuclear condensation, a considerable increase in micronuclei formation, and inhibition of the colony formation in A-375 cells treated with 7 µg/ml to 15 µg/ml of the extract. Wound-healing assay supported the anti-migration activity of the extract. Conclusion: T. persicum has significant antioxidant and cytotoxic properties. Surely, more detailed molecular and biochemical studies are needed to find the mechanism(s) behind these effects.

3D Bioprinted GelMA/PEGDA Hybrid Scaffold for Establishing an In Vitro Model of Melanoma.

Due to the high incidence of malignant melanoma, the establishment of in vitro models that recapitulate the tumor microenvironment is of great biological and clinical importance for tumor treatment and drug research. In this study, 3D printing technology was used to prepare GelMA/PEGDA composite scaffolds that mimic the microenvironment of human malignant melanoma cell (A375) growth and construct in vitro melanoma micro-models. The GelMA/PEGDA hybrid scaffold was tested by the mechanical property, cell live/dead assay, cell proliferation assay, cytoskeleton staining and drug loading assay. The growth of tumor cells in two- and three-dimensional culture systems and the anti-cancer effect of luteolin were evaluated using the live/dead staining method and the Cell Counting Kit-8 (CCK-8) method. The results showed a high aggregation of tumor cells on the 3D scaffold, which was suitable for long-term culture. Cytoskeleton staining and immunofluorescent protein staining were used to evaluate the degree of differentiation of tumor cells under 2D and 3D culture systems. The results indicated that 3D bioprinted scaffolds were more suitable for tumor cell expansion and differentiation, and the tumor cells were more aggressive. In addition, luteolin was time- and dose-dependent on tumor cells, and tumor cells in the 3D culture system were more resistant to the drug.

Role of long non-coding RNA 068 in the migration of melanoma cells / 中华皮肤科杂志

Objective:To investigate the effect of long non-coding RNA 068 (lncRNA 068) on the migration of a melanoma cell line A375, and to explore its mechanism of action.Methods:From December 2015 to November 2020, 21 patients with pathologically confirmed cutaneous melanoma were collected from Department of Dermatology, Affiliated Hospital of Nantong University, and quantitative PCR (qPCR) was performed to determine the expression of lncRNA 068 in melanoma and paracancerous tissues. LncRNA 068 was overexpressed or knocked down via lentiviral transfection in A375 human melanoma cells in the following experiments. Specifically, A375 cells were divided into lentiviral vector (LV) -green fluorescent protein (GFP) group and LV-lncRNA 068 group to be transfected with a GFP-expressing LV and a LV containing lncRNA 068 respectively in the overexpression experiment, and were divided into LV-LacZ short hairpin RNA (shRNA) group and LV-lncRNA 068 shRNA group to be transfected with a LV containing the reporter gene LacZ-specific shRNA and a LV containing the lncRNA 068-targeting shRNA respectively in the low-expression experiment, with the LV-GFP group and LV-LacZ shRNA group serving as the control groups. Transwell and scratch assays were performed to evaluate cell migration, EdU cell proliferation assay and cell counting kit-8 (CCK8) assay to determine the proportion of proliferative cells and cell viability respectively, and immunofluorescence staining was conducted to evaluate epithelial-mesenchymal transformation in the above groups. Lentivirus-transfected A375 cells from the above groups were inoculated into the axillae of BALB/c nude mice, and tumor volume was measured and calculated every 3 days. After 30 days, all mice were sacrificed, and tumor tissues were resected to measure the tumor volume and weight. Cultured B16F10 cells were subcutaneously inoculated into the back and foot of BALB/c nude mice to construct mouse models of subcutaneously transplanted B16F10 melanoma. After 2 weeks, the mice were sacrificed, and qPCR and Western blot analysis were performed to determine the mRNA expression of inflammatory factors in transplanted B16F10 melanoma and paracancerous tissues, and expression of IκB kinase (IKK) /P65 signaling pathway-related proteins, respectively. Comparisons between 2 groups were done by t test, and comparisons of tumor volume and weight at different time points among groups were done by repeated measures analysis of variance. Results:qPCR showed that the relative expression of lncRNA 068 was significantly lower in human melanoma tissues and transplanted B16F10 murine melanoma tissues (0.414 ± 0.109, 0.717 ± 0.041, respectively) than in the corresponding paracancerous tissues (1.050 ± 0.103, 1.011 ± 0.023, t = 19.48, 10.83, respectively, both P < 0.001). Transwell and scratch assays both showed that the cellular migratory ability was significantly lower in the LV-lncRNA 068 group than in the LV-GFP group (both P < 0.01), and significantly higher in the LV-lncRNA 068 shRNA group than in the LV-LacZ shRNA group (both P < 0.05). Immunofluorescence assay showed significantly increased fluorescence intensity of E-cadherin and decreased fluorescence intensity of N-cadherin in the LV-lncRNA 068 group compared with the LV-GFP group (both P < 0.001), but significantly decreased fluorescence intensity of E-cadherin and increased fluorescence intensity of N-cadherin in the LV-lncRNA 068 shRNA group compared with the LV-LacZ shRNA group (both P < 0.05). In vivo tumor formation experiment in nude mice showed that there were no significant differences in the volume or weight of melanoma between the LV-lncRNA 068 group and LV-GFP group (both P > 0.05), as well as between the LV-lncRNA 068 shRNA group and LV-LacZ shRNA group (both P > 0.05). As qPCR and Western blot analysis showed, the mRNA and protein expression of interleukin-10 (IL-10) and claudin-1 in A375 cells were significantly higher in the LV-lncRNA 068 group than in the LV-GFP group (both P < 0.05), but significantly lower in the LV-lncRNA 068 shRNA group than in the LV-LacZ shRNA group (both P < 0.05). Compared with the paracancerous tissues, B16F10 melanoma tissues showed significantly decreased mRNA expression of IL-10 ( P < 0.01), but significantly increased mRNA expression of IL-6 and tumor necrosis factor-α, as well as protein expression of phosphorylated P65 and phosphorylated IKK ( P < 0.01) . Conclusion:Overexpression of lncRNA 068 can inhibit the migration of A375 melanoma cells, and may affect the development of inflammation and inhibit the epithelial-mesenchymal transformation by inhibiting the IKK/P65 signaling pathway.

Effect of azacitidine on HOXA9 gene expression and biological behaviors of A375 melanoma cells / 中华皮肤科杂志

Objective:To investigate the effect of the methyltransferase inhibitor azacitidine (5-azaC) on the expression of homeobox A9 (HOXA9) gene in, as well as proliferation, invasion and migration of A375 cells.Methods:In vitro cultured A375 cells were treated with 5-azaC at various concentrations of 1, 5, 10 and 20 μmol/L, while routinely cultured A375 cells receiving no drug intervention served as control group. Methylation-specific PCR was performed to analyze methylation status of the HOXA9 gene promoter region after the treatment with different concentrations of 5-azaC, in order to screen the optimal concentration of 5-azaC for following experiments. Cell counting kit-8 (CCK8) assay was conducted to evaluate the proliferation of A375 cells, Transwell and wound healing assays were performed to estimate the invasion and migration of A375 cells, and real-time fluorescence-based quantitative PCR (qRT-PCR) and Western blot analysis were conducted to determine the mRNA and protein expression of HOXA9 in A375 cells after 5-azaC treatment. Two-independent-sample t test was used for comparisons between two groups. Results:Methylation was observed in the HOXA9 gene promoter region in A375 cells in the control group. After 5-azaC treatment, methylated and unmethylated states coexisted in the HOXA9 gene promoter region in A375 cells, and the higher the concentration of 5-azaC, the higher the degree of demethylation of the HOXA9 gene. Therefore, 20 μmol/L 5-azaC was selected to treat A375 cells for 72 hours, which served as 5-azaC treatment group in subsequent experiments. Compared with the control group, the 5-azaC treatment group showed significantly decreased cellular proliferative ability (72.46% ± 2.19% vs. 100%, t = 28.09, P < 0.001) , significantly decreased number of invasive cells (242.70 ± 29.19 vs. 466.00 ± 22.65, t = 10.47, P < 0.001) , significantly decreased migratory ability (27.56% ± 2.74% vs. 35.69% ± 2.50%, t = 3.79, P = 0.019) , significantly increased HOXA9 mRNA expression (1.73 ± 0.28 vs. 1.01 ± 0.15, t = 3.93, P = 0.017) , and significantly increased HOXA9 protein expression (0.62 ± 0.03 vs. 0.50 ± 0.01, t = 3.82, P = 0.019) . Conclusion:5-azaC can inhibit the proliferative, invasive and migratory ability of A375 melanoma cells, and one of the possible mechanisms underlying this process may be that 5-azaC reverses the methylation in the HOXA9 gene promoter region, activates HOXA9 gene expression, and participates in the regulation of biological behaviors of melanoma cells.

Bartonella henselae Detected in Malignant Melanoma, a Preliminary Study.

Bartonella bacilliformis (B. bacilliformis), Bartonella henselae (B. henselae), and Bartonella quintana (B. quintana) are bacteria known to cause verruga peruana or bacillary angiomatosis, vascular endothelial growth factor (VEGF)-dependent cutaneous lesions in humans. Given the bacteria's association with the dermal niche and clinical suspicion of occult infection by a dermatologist, we determined if patients with melanoma had evidence of Bartonella spp. infection. Within a one-month period, eight patients previously diagnosed with melanoma volunteered to be tested for evidence of Bartonella spp. exposure/infection. Subsequently, confocal immunohistochemistry and PCR for Bartonella spp. were used to study melanoma tissues from two patients. Blood from seven of the eight patients was either seroreactive, PCR positive, or positive by both modalities for Bartonella spp. exposure. Subsequently, Bartonella organisms that co-localized with VEGFC immunoreactivity were visualized using multi-immunostaining confocal microscopy of thick skin sections from two patients. Using a co-culture model, B. henselae was observed to enter melanoma cell cytoplasm and resulted in increased vascular endothelial growth factor C (VEGFC) and interleukin 8 (IL-8) production. Findings from this small number of patients support the need for future investigations to determine the extent to which Bartonella spp. are a component of the melanoma pathobiome.

Daphnoretin induces reactive oxygen species-mediated apoptosis in melanoma cells.

Research suggests that daphnoretin exhibits a diverse array of antitumor mechanisms and pharmacological activities. However, there is no definitive explanation for the antitumor mechanisms of daphnoretin in malignant melanoma. In the present study, MTT and colony formation assays demonstrated that daphnoretin significantly inhibited the proliferation of melanoma A375 and B16 cells. Following treatment with daphnoretin, apoptotic bodies were observed in A375 and B16 cells via Hoechst 33258 staining. Furthermore, western blot analysis revealed that the apoptosis-related proteins cleaved caspase-3, cleaved caspase-9, Bax, cytochrome c and apoptotic protease-activating factor 1 were significantly upregulated, while the expression levels of caspase-3, caspase-9 and Bcl-2 were downregulated in A375 and B16 cells. Flow cytometry and fluorescence microscopy revealed that daphnoretin induced higher levels of reactive oxygen species (ROS). Therefore, the results of the present study indicated that daphnoretin induced ROS-mediated mitochondria apoptosis in human (A375) and murine (B16) malignant melanoma cells.

Externally added cystatin C reduces growth of A375 melanoma cells by increasing cell cycle time.

Some secreted cysteine protease inhibitors of the cystatin family appear to affect intracellular proteolysis and growth of human cells, as a result of internalization. Here, we studied the effects of external addition of the most abundant human cystatin, cystatin C, on viability and proliferation of cancer cells in culture. A dose-dependent decrease in viable cells was seen for A375 melanoma, MCF-7 breast cancer, and PC-3 prostate cancer cells cultured in 1-5 µm cystatin C after 24 h. Real-time assessment of growth rates in A375 cell cultures for 48 h by digital holographic microscopy showed an increased doubling time for cells cultured in the presence of 5 µm cystatin C (20.1 h) compared with control cells (14.7 h). A prolonged doubling time was already observed during the first 12 h, indicating a rapid general decrease in cell proliferation at the population level. Tracking of individual cells in phase holographic images showed that dividing cells incubated with 5 µm cystatin C underwent fewer mitoses during 48 h than control cells. In addition, the time between cell divisions was longer, especially for the first cell cycle. Incubation with the variant W106F-cystatin C (with high cellular uptake rate) resulted in a lower number of viable cells and a prolonged doubling time than when cells were incubated with wild-type cystatin C, but no effect was observed for (R24A,R25A)-cystatin C (low cellular uptake). Thus, cystatin C causes prolonged cell division leading to decreased proliferation of melanoma cells, and internalization seems to be a prerequisite for this effect.

ZNF750 inhibits the proliferation and invasion of melanoma cells through modulating the Wnt/b-catenin signaling pathway.

INTRODUCTION: The abnormal expression of Zinc Finger Protein 750 (ZNF750) has been reported in neoplastic diseases. This study investigated the functional role of ZNF750 in the progression of melanoma. MATERIAL AND METHODS: Quantitative real-time PCR and immunohistochemistry (IHC) were performed to detect the expression levels of ZNF750 in patients diagnosed with primary cutaneous malignant melanoma. The correlation between clinical-pathological features and ZNF750 expression were clarified. Cell Counting Kit-8 (CCK-8), colony formation and transwell assays were used to explore the effects of ZNF750 on the proliferation, colony formation, migration and invasion of melanoma cells. Western blot assay was used to evaluate the effects of ZNF750 on regulating epithelial-mesenchymal transition (EMT) related proteins. RESULTS: ZNF750 expression was down-regulated in human melanoma tissues and cells, and correlated with the clinical-pathological features including tumor size, lymph node metastasis, and Clark classification in patients with melanoma. In addition, overexpression of ZNF750 decreased the proliferation, invasion and suppressed EMT of melanoma cells, whereas ZNF750 depletion showed the opposite effects. Importantly, mechanistic analyses implied that upregulation of ZNF750 inhibited the expression of b-catenin and the downstream targets (cyclin D1, c-Myc, Bcl-2, MMP2 and MMP9), indicating it could block the activation of Wnt/b-catenin pathway. Consistently, knockdown of ZNF750 led to the opposite results. CONCLUSIONS: Together, ZNF750 serves as a tumor suppressor for the development and progression of melanoma through regulating the Wnt/b-catenin pathway. This study confirms the involvement of ZNF750 in melanoma progression and may provide a promising therapeutic target for the treatment of melanoma.

The Anti-tumor Effects of p-Coumaric Acid on Melanoma A375 and B16 Cells.

Background: Existing research shows that p-coumaric acid (p-CA) can inhibit the proliferation of a variety of tumor cells in vitro. However, there are no reports on the anti-tumor effects of p-CA on melanoma cells. In this study, the inhibitory effects of p-CA on mouse melanoma B16 and human melanoma A375 cells are reported, and the related mechanisms are investigated. Methods: CCK-8 assay was used to detect the effects of p-CA on cell vitality, colony formation assay was used to observe the effects on cell proliferation, Hoechst 33,258 staining was used to observe the morphology of apoptotic cells, flow cytometry was used to detect the effects on apoptosis and the cell cycle, and western blot was used to measure the levels of cell cycle- and apoptosis-related signaling pathway proteins. Results: p-CA significantly inhibits cell proliferation of A375 and B16 cells in a dose-dependent manner and obviously induced cell morphological changes. p-CA arrested A375 cells in the S phase by downregulating the cell cycle-related proteins Cyclin A and CDK2, and arrested B16 cells in the G0-G1 phase through downregulating the cell cycle-related proteins Cyclin E and CDK2. In addition, p-CA significantly promoted apoptosis of A375 and B16 cells. Furthermore, p-CA significantly upregulated the levels of Apaf1 and Bax and downregulated the levels of Bcl-2, and subsequently increased the levels of cytoplasmic cytochrome c (Cyto-c), cleaved caspase-3, and cleaved caspase-9, leading to apoptosis in A375 and B16 cells. Conclusion: p-CA can significantly inhibit the proliferation of human and mouse melanoma cells in vitro. Our research is a step in the development of anti-melanoma drugs.

9-phenyl acridine photosensitizes A375 cells to UVA radiation.

Acridines are an important class of bioactive molecules having varied uses. Its derivative, 9-phenylacridine (ACPH) had been found to exhibit antitumor activity both in cell lines and in vivo model. Its DNA binding ability and absorbance in the ultraviolet range encouraged us to investigate its role as a photosensitizer with UVA radiation. We investigated the effects of ACPH prior to UVA exposure on in vitro DNA through photo-cleavage assay. Effect of such treatment was also studied in cultured A375 melanoma cells. Endpoints studied included morphological changes, evaluation of cellular viability, scratch assay, intracellular reactive oxygen species (ROS) production, DNA damage, lipid peroxidation, glutathione (GSH) level, autophagy, cell cycle progression, depletion of mitochondrial membrane potential (ΔΨmt), induction of apoptosis and Hoechst dye efflux assay. Our findings indicated that ACPH could sensitize damage to DNA induced by UVA both in vitro and in cells. It could also potentiate cell killing by UVA. It arrested cells in G2/M phase and induced apoptotic death through mitochondria mediated pathway. This sensitization was through enhancement of intracellular ROS. Our findings also indicated that the stem cells side population was reduced on such treatment. The findings are important as it indicates ACPH as a promising photosensitizer and indicates its possible role in photodynamic therapy.

Cell Cycle Regulation by Berberine in Human Melanoma A375 Cells.

We studied the effects of berberine on the proliferation, apoptosis, and migration of skin melanoma A375 cells, as well as cell cycle-related miRNAs and their target genes, CDK1, CDK2, and cyclins D1 and A. The inhibitory effect of berberine on the growth of A375 cells was evaluated by MTT assay. Cell apoptosis was detected by trypan blue staining. Cell migration was assessed by the scratch test. Cell cycle phases were determined by flow cytometry. The levels of miRNA-582-5p and miRNA-188-5, and mRNA of their target genes encoding CDK1, CDK2, and cyclins D1 and A were measured by qRT-PCR. The expression of cell cycle-related proteins (CDK1, CDK2, and cyclins D1 and A) was determined by Western blotting. Berberine inhibited the proliferation of A375 cells in a time- and dose-dependent manner and significantly and dose-dependently enhanced cell apoptosis. Scratch assay showed an inhibitory effect of berberine on migration of A375 cells. Berberine in low concentrations (20 and 40 µM) caused cell cycle arrest in the S and G2/M phases, while treatment with high concentrations of berberine (60 and 80 µM) arrested cell-cycle in the G2/M phase. The increase in berberine concentration led to an increase in miRNA-582-5p and miRNA-188-5p expression and a decrease in the expression of mRNA for the corresponding target genes encoding CDK1, CDK2, and cyclins D1 and A. Western blotting also revealed reduced expression of CDK1, CDK2, and cyclins D1 and A. Thus, berberine suppressed the growth and migration of human melanoma cells and promoted their apoptosis. Berberine can increase the expression of cell cycle-related miRNAs and cause degradation of the corresponding target genes, thereby blocking the cell cycle progression and inhibiting the melanoma A375 cells.

Substantial Cellular Penetration of Fluorescent Imidazoquinoxalines.

Fluorescent tools have revolutionized our capability to visualize, probe, study, and understand the biological cellular properties, processes and dynamics, enabling researchers to improve their knowledge for example in cancer field. In this paper, we use the peculiar properties of our Imiqualines derivatives to study their cellular penetration and distribution in a human melanoma cell line A375 using confocal microscopy. Preliminary results on colocalization with the potent protein target c-Kit of our lead are also described.

S-petasin induces apoptosis and inhibits cell migration through activation of p53 pathway signaling in melanoma B16F10 cells and A375 cells.

Melanoma is a dangerous type of skin cancer that develops from the melanocytes. Activation of p53 in melanoma cells has been validated as a strategy for melanoma therapy. S-Petasin, a dietary sesquiterpene isolated from Petasites japonicus, has been shown to possess multiple biological effects. However, no studies have reported that s-petasin exerted anti-melanoma or inhibited activity in melanoma cells. We investigated the effect of s-petasin in B16F10 cells and A375 cells and the underlying molecular mechanism. S-Petasin exerted a significant anti-proliferation effect on B16F10 cells and A375 cells as measured by the MTT assay and crystal violet staining assay. S-Petasin induced cell apoptosis in B16F10 cells and A375 cells as evidenced by flow cytometry assay and western blot assay. Wound healing assay and transwell cell migration and invasion assay revealed that s-petasin suppressed B16F10 cells and A375 cells migration in vitro. For mechanism study, western blot assay indicated that s-petasin activated the p53 pathway signaling. Furthermore, expression of Bcl-2, Bcl-XL, Bax, MMP-2, MMP-9, p21, CDK4 and cyclin D1 were regulated by s-petasin. Taken together, our data suggest that s-petasin is a novel compound which can induce apoptosis and inhibit cell migration through activation of the p53 pathway signaling in melanoma B16F10 cells and A375 cells.