Autophagy is a natural regulatory mechanism of the cell that eliminates unnecessary and dysfunctional cellular components to maintain homeostasis. Several authors have demonstrated that this mechanism can be induced by pathological conditions as cancer. However, their role in tumor development is still a controversial issue in cancer research. Here, we discussed the most relevant findings concerning autophagy in tumor development. In this critical review performed with studies published between 2002 and 2018, we found that the main pathway involved in the autophagy process is the PI3K/AKT/mTOR intracellular signaling pathway. Regarding their role in cancer development, breast cancer is the main study target, followed by lung, prostate and colon cancer. In these issues, 46% of the works consulted suggesting that autophagy inhibits tumor progression by favor a better antitumor response, 4% suggest that favors growth and tumor progression and, 50% of the authors failed to establish whether autophagy inhibits or favors tumor development. Herein, we concluded that depending on the study model, autophagy may favor or inhibits growth and cancer progression.

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自噬在肿瘤发展中的争议作用：系统综述。

自噬是细胞的天然调节机制，可消除不必要和功能失调的细胞成分，以维持体内平衡。几位作者证明了这种机制可以由病理状态如癌症诱导。然而，它们在肿瘤发展中的作用仍然是癌症研究中有争议的问题。在这里，我们讨论了有关肿瘤发展中自噬的最相关发现。在2002年至2018年发表的这项研究的重要综述中，我们发现自噬过程涉及的主要途径是PI3K / AKT / mTOR细胞内信号传导途径。关于它们在癌症发展中的作用，乳腺癌是主要的研究对象，其次是肺癌，前列腺癌和结肠癌。在这些问题中，所咨询的研究中有46％的研究表明自噬通过支持更好的抗肿瘤反应而抑制肿瘤的发展，4％的研究表明自噬抑制了肿瘤的生长和进展，还有50％的作者未能确定自噬是抑制还是促进肿瘤的发展。在此，我们得出结论，根据研究模型，自噬可能会促进或抑制生长和癌症进展。