Combined Effect of Cold Atmospheric Plasma and Curcumin in Melanoma Cancer

Mechanism of non-thermal atmospheric plasma in anti-tumor: influencing intracellular RONS and regulating signaling pathways

Non-thermal atmospheric plasma (NTAP) has been proven to be an effective anti-tumor tool, with various biological effects such as inhibiting tumor proliferation, metastasis, and promoting tumor cell apoptosis. At present, the main conclusion is that ROS and RNS are the main effector components of NTAP, but the mechanisms of which still lack systematic summary. Therefore, in this review, we first summarized the mechanism by which NTAP directly or indirectly causes an increase in intracellular RONS concentration, and the multiple pathways dysregulation (i.e. NRF2, PI3K, MAPK, NF-κB) induced by intracellular RONS. Then, we generalized the relationship between NTAP induced pathways dysregulation and the various biological effects it brought. The summary of the anti-tumor mechanism of NTAP is helpful for its further research and clinical transformation.

Effect of cold atmospheric plasma on changing of biomolecular structures involved in apoptosis pathways of melanoma cancer

BACKGROUND

Cold atmospheric plasma (CAP), is a technology based on non-thermal ionized gas that is used for cancer therapy in research. We evaluated the effect of CAP on malignant melanoma cancer cell line (B16) in comparison with normal cells (L929).

METHODS

The effect of CAP on the cytotoxicity of B16 and L929 cell lines was assayed by the MTT method and inverted microscopy. The induction of apoptosis in cells was evaluated using a fluorescence microscope. FTIR monitored the CAP effect in biomacromolecules changes in these cell lines. QPCR assayed gene expression of BAX, BCL-2, and Caspase-3 (CASP-3).

RESULTS

The results of the MTT test showed CAP has a cytotoxic effect on the B16 cancer cell line more than L929 normal cells (p < 0.0001). The results of invert and fluorescence microscopy showed CAP-induced apoptotic morphology on cancerous cells. FTIR spectroscopy indicated CAP changes biomacromolecules structure. Evaluation of gene expression showed CAP increased BAX and CASP-3 gene expression. Also, it decreased BCL-2 gene expression.

CONCLUSIONS

Taken together, CAP may change biomacromolecule structures involved in apoptosis pathways, decrease proliferation and induce apoptosis in cancer cells.

Prosopis juliflora (Sw.) DC phytochemicals induce apoptosis and inhibit cell proliferation signaling pathways, EMT, migration, invasion, angiogenesis and stem cell markers in melanoma cell lines

ETHNOPHARMACOLOGICAL RELEVANCE

Prosopis juliflora (Sw.), DC is a xerophytic plant species that extensively grow in Asia, Africa, Australia, and Brazil. From ancient time P. juliflora is being utilized in various folk remedies for example in wound healing, fever, inflammation, measles, excrescences, diarrhea and dysentery. Traditionally, gum, paste, and smoke obtained from the leaves and pods are applied for anticancer, antidiabetic, anti-inflammatory, and antimicrobial purposes.

AIM OF THE STUDY

Our previous studies have demonstrated the promising potential of Prosopis Juliflora leaves methanol extract (PJLME) against breast cancer, and suggested its possible integration as a complementary medicine for the effective management of breast cancer. However, evidence against how PJLME mechanistically target the cancer proliferative pathways and other targets is poorly understood. The basic aim of the present study was to understand the anti-melanoma potential of PJLME against B16f10 cells with possible mechanisms of action.

MATERIALS AND METHODS

MTT assay was used to determine cell viability. Wound and transwell migration assay was performed to check migration potential of cells after PJLME treatment, while clonogenic assay was carried out to understand its colony inhibition actvity. Flow cytometry was used to perform annexin V/PI assay (apoptosis assay), ROS assay, cell cycle analysis. In-vitro angiogenesis assay was performed to check formation of capillary like vascular structure after PJLME treatment. Apoptotic genes, signaling pathways markers, EMT markers and stem cell markers were determined by western blotting. In-vivo BALB/C mice xenograft model study was performed to check the effect of PJLME on in-vivo melanoma tumor growth.

RESULTS

The experimental outcome of the present study has clearly demonstrated the inhibition of growth, migration, invasion, colony formation and apoptosis inducing potential of PJLME against mouse melanoma cancer cells. Treatment of B16F10 melanoma cells with PJLME resulted in arrest of cell cycle at G0/G1 phase. Annexin V-FITC/PI assay confirmed the apoptosis inducing potential of PJLME in B16F10 and A375 melanoma cells. Furthermore, Western blot experiments confirmed that the treatment of PJLME downregulates the expression of anti-apoptotic gene like Bcl2 and increase the expression profile of pro-apoptotic genes like Bax, Bad, and Bak in B16F10 melanoma cells. HUVEC (Human umbilical vein endothelial cells) tube formation assay clearly demonstrated the anti-angiogenic potential of PJLME. The study also revealed that PJLME has potential to inhibit the Akt and Erk signaling pathways which are participating in cancer cell proliferation, migration, invasion etc. The outcome of qRT-PCR and immunoblotting analysis clearly unveiled that PJLME treatment leads to downregulation of epithelial-mesenchymal transition (EMT) as well as stem cell markers. Finally, the in-vivo animal xenograft model study also revealed the anti-melanoma potential of PJLME by significantly inhibiting the B16F10 melanoma tumor growth in BALB/c mice model. The LC-ESI-MS/MS analysis of PJLME showed the presence of variety of bioactive molecules associated with anticancer effects.

CONCLUSION

The outcome of the present investigation clearly demonstrated the anti-melanoma potential of PJLME against B16f10 melanoma cells. PJLME can be explored as an adjuvant or complementary therapy against melanoma cancer, however further studies are required to understand the clinical efficacy of PJLME. Nevertheless, it can be further explored as a promising resource for identification of novel anticancer candidate drug.

Recent advances in cold atmospheric plasma (CAP) for breast cancer therapy

The serious problems of conventional breast cancer therapy strategies such as drug resistance, severe side effects, and lack of selectivity prompted the development of various cold atmospheric plasma (CAP) devices. Due to its advanced technology, CAP can produce a unique environment rich in reactive oxygen and nitrogen species (RONS), photons, charged ions, and an electric field, making it a promising revolutionary platform for cancer therapy. Despite substantial technological successes, CAP-based therapeutic systems are encounter with distinct limitations, including low control of the generated RONS, poor knowledge about its anticancer mechanisms, and challenges concerning designing, manufacturing, clinical translation, and commercialization, which must be resolved. The latest developments in CAP-based therapeutic systems for breast cancer treatment are discussed in this review. More significantly, the integration of CAP-based medicine approaches with other breast cancer therapies, including chemo- and nanotherapy is thoroughly addressed.

Combination effect of cold atmospheric plasma with green synthesized zero-valent iron nanoparticles in the treatment of melanoma cancer model

Green synthesized zero-valent iron nanoparticles (nZVI) have high potential in cancer therapy. Cold atmospheric plasma (CAP) is also an emerging biomedical technique that has great potential to cure cancer. Therefore, the combined effect of CAP and nZVI might be promising in treatment of cancer. In this study, we evaluated the combined effect of CAP and nZVI on the metabolic activity of the surviving cells and induction of apoptosis in malignant melanoma in comparison with normal cells. Therefore, the effect of various time exposure of CAP radiation, different doses of nZVI, and the combined effect of CAP and nZVI were evaluated on the viability of malignant melanoma cells (B16-F10) and normal fibroblast cells (L929) at 24 h after treatment using MTT assay. Then, the effect of appropriate doses of each treatment on apoptosis was evaluated by fluorescence microscopy and flow cytometry with Annexin/PI staining. In addition, the expression of BAX, BCL2 and Caspase 3 (CASP3) was also assayed. The results showed although the combined effect of CAP and nZVI significantly showed cytotoxic effects and apoptotic activity on cancer cells, this treatment had no more effective compared to CAP or nZVI alone. In addition, evaluation of gene expression showed that combination therapy didn't improve expression of apoptotic genes in comparison with CAP or nZVI. In conclusion, combined treatment of CAP and nZVI does not seem to be able to improve the effect of monotherapy of CAP or nZVI. It may be due to the resistance of cancer cells to high ROS uptake or the accumulation of saturated ROS in cells, which prevents the intensification of apoptosis.

The combined effect of fish oil containing Omega-3 fatty acids and Lactobacillus plantarum on colorectal cancer

Colorectal cancer (CRC) is one of the deadliest malignancies. Recent attempts have indicated the role of diet in the etiology of CRC. Natural dietary compounds such as probiotics and Omega-3 fatty acids that act synergistically can be beneficial in finding a tremendous solution against CRC. To date, the combined effect of fish oil containing Omega-3 fatty acids (Omega-3) and Lactobacillus plantarum (L. plantarum) on CRC has been left behind. We here evaluated the effects of co-encapsulation of Omega-3 and probiotic bacteria on CRC cell lines compared to normal cells. Omega-3 and L. plantarum bacteria were co-encapsulated in three ways, including gelatin-gum Arabic, gelatin-chitosan, and chitosan-gum Arabic complex coacervate microcapsules. After treatment of cells (Normal [L929] and colorectal [C26]) by L. plantarum, Omega-3, and microcapsules, viability and growth capacity of cell lines were measured using the MTT (3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide) assay. Isolated total RNA was used to evaluate the expression profile of BCL2-associated X protein (BAX), B-cell lymphoma 2 (BCL-2), and Caspase-3 (CASP3) genes by real-time polymerase chain reaction (PCR). Statistical analysis was performed with SPSS 25 software. A value of p < .05 was considered statistically significant. The results indicated a significant reduction in cell viability of C26 in a concentration-dependent manner in the treated cells with all treatments, except gelatin-gum Arabic microcapsules. The messenger RNA (mRNA) expression level of the BAX and CASP3 genes in C26 cells being treated with all treatments significantly increased than in untreated cells, and the expression level of the anti-apoptotic factor of the BCL-2 gene decreased in C26 cells simultaneously (p < .05). Although, the combined effect of Omega-3 and L. plantarum and microcapsulated treatments had no more effect on viability and apoptosis gene expression of cancer cells compared to Omega-3 or L. plantarum. In conclusion, combination therapy with fish oil containing Omega-3 and L. plantarum does not improve the anticancer effect of each alone.

Cold atmospheric pressure plasma treatment combined with starvation increases autophagy and apoptosis in melanoma in vitro and in vivo

Despite advances in therapy, malignant melanoma remains a fatal disease. Among several emerging approaches to combat cancer, cold atmospheric pressure plasma (CAP) has shown promising results as a novel antitumor agent in preclinical models so far. The technology mainly relies on the emittance of various reactive oxygen and nitrogen species (ROS/RNS) that are tumor-toxic at high concentrations. Moreover, malignant melanoma has a metabolic dimension that can be targeted by mild starvation. To this end, we investigated the combined effect of starvation and CAP treatment on melanoma in vitro and in vivo. In vitro, starvation+CAP led to cell morphology changes, decreased metabolic activity and increased lipid peroxidation accompanied by apoptosis and DNA fragmentation in murine B16 melanoma cells but not murine non-malignant L929 fibroblasts. This was paralleled by increased apoptosis (Bax, Bcl-2 and Caspase-3) and autophagy (Lc3 and Atg5)-related gene expression. In vivo, starvation reduced tumor burden. Combination with CAP treatment augmented this effect significantly, albeit there was no difference of combination treatment to CAP exposure alone. Interestingly, there was an overall greater increase of Lc3 and Atg5 in the tumor tissue compared to CAP exposure alone, while starvation-induced autophagy-related gene expression was similar to in the combination group. These data collectively suggest that CAP-derived ROS/RNS treatment and autophagy-induction augment antitumor effects in malignant melanoma in vitro and in vivo.

Lack of Adverse Effects of Cold Physical Plasma-Treated Blood from Leukemia Patients: A Proof-of-Concept Study

Chronic lymphocytic leukemia (CLL) is the most common blood malignancy with multiple therapeutic challenges. Cold physical plasma has been considered a promising approach in cancer therapy in recent years. In this study, we aimed to evaluate the cytotoxic effect of cold plasma or plasma-treated solutions (PTS) on hematologic parameters in the whole blood of CLL patients. The mean red blood cell count, white blood cell (WBC) count, platelet and hemoglobin counts, and peripheral blood smear images did not significantly differ between treated and untreated samples in either CLL or healthy individuals. However, both direct plasma and indirect PTS treatment increased lipid peroxidation and RNS deposition in the whole blood of CLL patients and in healthy subjects. In addition, the metabolic activity of WBCs was decreased with 120 s of cold plasma or PTS treatment after 24 h and 48 h. However, cold plasma and PTS treatment did not affect the prothrombin time, partial thromboplastin time, nor hemolysis in either CLL patients or in healthy individuals. The present study identifies the components of cold plasma to reach the blood without disturbing the basic parameters important in hematology, confirming the idea that the effect of cold plasma may not be limited to solid tumors and possibly extends to hematological disorders. Further cellular and molecular studies are needed to determine which cells in CLL patients are targeted by cold plasma or PTS.