Pulsed Electromagnetic Fields (PEMFs) Trigger Cell Death and Senescence in Cancer Cells.

The currently available anti-cancer therapies, such as gamma-radiation and chemotherapeutic agents, induce cell death and cellular senescence not only in cancer cells but also in the adjacent normal tissue. New anti-tumor approaches focus on limiting the side effects on normal cells. In this frame, the potential anti-tumor properties of Pulsed Electromagnetic Fields (PEMFs) through the irradiation of breast cancer epithelial cells (MCF-7 and MDA-MB-231) and normal fibroblasts (FF95) were investigated. PEMFs had a frequency of 8 Hz, full-square wave type and magnetic flux density of 0.011 T and were applied twice daily for 5 days. The data collected showcase that PEMF application decreases the proliferation rate and viability of breast cancer cells while having the opposite effect on normal fibroblasts. Moreover, PEMF irradiation induces cell death and cellular senescence only in breast cancer cells without any effect in the non-cancerous cells. These findings suggest PEMF irradiation as a novel, non-invasive anti-cancer strategy that, when combined with senolytic drugs, may eliminate both cancer and the remaining senescent cells, while simultaneously avoiding the side effects of the current treatments.

Helicobacter pylori Eradication Reverses DNA Damage Response Pathway but Not Senescence in Human Gastric Epithelium.

Helicobacter pylori (H. pylori) infection induces DNA Double-Strand Breaks (DSBs) and consequently activates the DNA Damage Response pathway (DDR) and senescence in gastric epithelium. We studied DDR activation and senescence before and after the eradication of the pathogen. Gastric antral and corpus biopsies of 61 patients with H. pylori infection, prior to and after eradication treatment, were analyzed by means of immunohistochemistry/immunofluorescence for DDR marker (γH2AΧ, phosporylated ataxia telangiectasia-mutated (pATM), p53-binding protein (53BP1) and p53) expression. Samples were also evaluated for Ki67 (proliferation index), cleaved caspase-3 (apoptotic index) and GL13 staining (cellular senescence). Ten H. pylori (-) dyspeptic patients served as controls. All patients were re-endoscoped in 72-1361 days (mean value 434 days), and tissue samples were processed in the same manner. The eradication of the microorganism, in human gastric mucosa, downregulates γH2AΧ expression in both the antrum and corpus (p = 0.00019 and p = 0.00081 respectively). The expression of pATM, p53 and 53BP1 is also reduced after eradication. Proliferation and apoptotic indices were reduced, albeit not significantly, after pathogen clearance. Moreover, cellular senescence is increased in H. pylori-infected mucosa and remains unaffected after eradication. Interestingly, senescence was statistically increased in areas of intestinal metaplasia (IM) compared with adjacent non-metaplastic mucosa (p < 0.001). In conclusion, H. pylori infection triggers DSBs, DDR and senescence in the gastric epithelium. Pathogen eradication reverses the DDR activation but not senescence. Increased senescent cells may favor IM persistence, thus potentially contributing to gastric carcinogenesis.

The DNA damage response and autophagy during cancer development: an antagonistic pleiotropy entanglement.

The DNA damage response (DDR) pathway is a cardinal cellular stress response mechanism that during cancer development follows an antagonistic pleiotropy mode of action. Given that DDR activation is an energy demanding process, interplay with macroautophagy/autophagy, a stress response and energy providing mechanism, is likely to take place. While molecular connections between both mechanisms have been reported, an open question regards whether autophagy activation follows solely or is entangled with DDR in a similar antagonistic pleiotropy pattern during cancer development. Combing evidence on the spatiotemporal relationship of DDR and autophagy in the entire spectrum of carcinogenesis from our previous studies, we discuss these issues in the current addendum.Abbreviation: AMPK: AMP-dependent protein kinase; DDR: DNA damage response.

A Single Center, Randomized Controlled Trial on the Efficacy of Topical Application of ReGenerating Tissue Agents (RGTA) Technology in Diabetic Foot Ulcers.

Diabetic foot ulcers (DFUs) are a serious complication of diabetes mellitus. Clinical data from the use of ReGenerating Tissue Agents (RGTA) technology in patients with DFUs are scarce. The objective of this randomized controlled study was to evaluate the efficacy of RGTA technology in the management of DFUs. Patients with chronic, neuroischemic diabetic foot ulcers were randomized 1:1 to the control group, that received the standard of care, and to the intervention group, that additionally received RGTA twice per week. The duration of the intervention was 12 weeks. Skin biopsies for histological and immunohistochemical analyses from a sample of participants were also performed. About 31 patients completed the study. Five (31.2%) patients in the intervention group achieved complete healing at the end of the intervention period versus 0 patients in the control group (P = .043), [RR: 0.688 (95% CI: 0.494-0.957)]. The intervention group had more ulcers with at least 80% healing of their surface [10 (66.7%) versus 2 (13.3%), P = .008, RR: 0.385 (95% CI: 0.183-0.808)], higher absolute surface reduction [1.5 (0.7, 5.2) versus 0.6 (0.3, 1.0), P = .026] and higher percentages of surface reduction [94 (67, 100) versus 40 (26, 75), P = .001] at the end of the intervention period. More patients in the intervention group achieved at least 50% healing at the fourth week of the study [9 (64.3%) versus 2 (14.3%) P = .018, RR: 0.417 (95% CI: 0.200-0.869)]. Immunohistochemical analyses were performed in a sample of participants that revealed higher expression of CD163, COL3 and VEGFR in the intervention group. The adverse effects were similar between the 2 groups. The data from the present study suggest that the adjunction of RGTA technology in the management of diabetic foot ulcers is a safe practice that promotes wound healing.

One-step rapid tracking and isolation of senescent cells in cellular systems, tissues, or animal models via GLF16.

Identification and isolation of senescent cells is challenging, rendering their detailed analysis an unmet need. We describe a precise one-step protocol to fluorescently label senescent cells, for flow cytometry and fluorescence microscopy, implementing a fluorophore-conjugated Sudan Black-B analog, GLF16. Also, a micelle-based approach allows identification of senescent cells in vivo and in vitro, enabling live-cell sorting for downstream analyses and live in vivo tracking. Our protocols are applicable to cellular systems, tissues, or animal models where senescence is present. For complete details on the use and execution of this protocol, please refer to Magkouta et al.1.