Metformin Suppresses Self-Renewal Ability and Tumorigenicity of Osteosarcoma Stem Cells via Reactive Oxygen Species-Mediated Apoptosis and Autophagy

<div>Metformin regulates autophagy via the AMPK/mTOR pathway. (a) Western blot analysis and (b) densitometric analyses of metformin on the AMPK pathway in K7M2 OSCs and MG63 OSCs. (c) Western blot and (d) densitometric analyses of compound C on metformin-mediated autophagy in K7M2 and MG63 OSCs. (e) TEM images of autophagosomes in the compound C-treated K7M2 and MG63 OSCs. The pentagrams stand for autophagosomes. <span class="nowrap"><svg height="12.7373pt" id="M125" style="vertical-align:-3.429399pt" version="1.1" viewbox="-0.0498162 -9.3079 91.9897 12.7373" width="91.9897pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M409 504C401 567 396 607 392 642C354 654 312 665 266 665C137 665 60 583 60 487C60 374 161 325 225 290C300 250 355 215 355 141C355 68 311 21 235 21C131 21 86 122 71 183L41 176C48 128 61 42 68 21C78 16 93 8 118 0C142 -7 175 -15 216 -15C349 -15 438 69 438 174C438 287 344 333 265 374C186 414 138 449 138 522C138 576 172 631 249 631C336 631 363 562 380 499L409 504Z"></path></g><g transform="matrix(.013,0,0,-0.013,6.345,0)"><path d="M390 111C344 68 312 56 269 56C212 56 118 102 118 241C118 346 175 401 241 401C277 401 312 388 342 360C350 352 355 349 361 349C372 349 394 371 394 392C394 403 391 411 378 422C362 436 329 449 288 449H287C250 449 190 432 138 392C71 341 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Oxidative Medicine and Cellular Longevity

fig5

Figure 5

Figure 5: Metformin Suppresses Self-Renewal Ability and Tumorigenicity of Osteosarcoma Stem Cells via Reactive Oxygen Species-Mediated Apoptosis and Autophagy 

Figure 5 | Metformin Suppresses Self-Renewal Ability and Tumorigenicity of Osteosarcoma Stem Cells via Reactive Oxygen Species-Mediated Apoptosis and Autophagy 