Metformin’s Effects on Apoptosis of Esophageal Carcinoma Cells and Normal Esophageal Epithelial Cells: An In Vitro Comparative Study

<div>Relationship between metformin-induced cell apoptosis and the level of intracellular ROS in EC109 cells and HEECs. (a) The apoptotic index (%) of EC109 cells and HEECs was determined by flow cytometry analysis using Annexin V-FITC/PI double staining upon treatment with metformin and/or NAC. (b) Cells were imaged on a fluorescence microscope after treatment with the indicated concentration of metformin or H<sub>2</sub>O<sub>2</sub> for 24 h (magnification ×400). (c, d) Flow cytometry was used to detect the intracellular ROS levels after the indicated concentration of metformin for 24 h and preincubation with 5.0 mM NAC for 2 h before exposure to 5.0 mM metformin for 24 h. Data were presented as mean ± SD (<i>n</i> = 3). <svg height="11.6791pt" id="M7" style="vertical-align:-1.5766pt" version="1.1" viewbox="-0.0498162 -10.1025 208.437 11.6791" width="208.437pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.0091,0,0,-0.0091,0,-5.741)"><path d="M486 158C486 177 478 202 466 220C413 228 386 236 336 262C386 288 413 297 466 304C478 323 486 347 485 366C470 376 444 381 422 380C389 338 368 319 321 288C323 345 329 372 349 422C339 442 322 461 305 470C289 461 271 442 262 422C281 372 287 345 290 288C243 319 222 338 189 380C167 381 142 376 125 366C125 347 133 322 145 304C198 296 225 288 275 262C225 236 198 227 145 220C133 201 125 177 126 158C141 148 167 143 189 144C222 186 243 205 290 236C288 179 282 152 262 102C272 82 289 63 306 54C322 63 340 82 350 102C330 152 324 179 321 236C368 205 390 186 422 144C444 143 470 148 486 158Z"></path></g><g transform="matrix(.013,0,0,-0.013,6.079,0)"><path d="M600 480C600 590 528 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602Z"></path></g><g transform="matrix(.013,0,0,-0.013,186.141,0)"><path d="M113 -12C146 -12 170 11 170 46C170 78 146 103 114 103S58 78 58 46C58 11 82 -12 113 -12Z"></path></g><g transform="matrix(.013,0,0,-0.013,189.105,0)"><path d="M241 635C89 635 35 457 35 312C35 153 89 -12 240 -12C390 -12 443 166 443 312C443 466 390 635 241 635ZM238 602C329 602 354 454 354 312C354 172 330 22 240 22C152 22 124 173 124 313S148 602 238 602Z"></path></g><g transform="matrix(.013,0,0,-0.013,195.345,0)"><path d="M241 635C89 635 35 457 35 312C35 153 89 -12 240 -12C390 -12 443 166 443 312C443 466 390 635 241 635ZM238 602C329 602 354 454 354 312C354 172 330 22 240 22C152 22 124 173 124 313S148 602 238 602Z"></path></g><g transform="matrix(.013,0,0,-0.013,201.585,0)"><path d="M384 0V27C293 34 287 42 287 114V635C232 613 172 594 109 583V559L157 557C201 555 205 550 205 499V114C205 42 199 34 109 27V0H384Z"></path></g></svg> versus the corresponding control. CON: control; MET: metformin.</div>

BioMed Research International

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Figure 4

Figure 4: Metformin’s Effects on Apoptosis of Esophageal Carcinoma Cells and Normal Esophageal Epithelial Cells: An In Vitro Comparative Study 