**3. Conclusions**

Downregulation of the ASncmtRNAs has been assessed in several tumor tissues, such as bladder, prostate, kidney, ovary, cervix and breast, among others [58]. The role of these transcripts in cell proliferation and tumorigenesis is not fully understood at present. However, downregulation of the ASncmtRNAs while maintaining the expression of SncmtRNA represents a universal characteristic of tumor cells. The strong inhibition of tumor growth, induction of apoptosis and even tumor remission after knockdown of these RNAs *in vivo* is an impressive phenomenon that constitutes a unique opportunity for the development of a targeted therapy against several types of cancer. Moreover, the fact that antisense therapy does not cause side effects constitutes an attribute not observed in other kinds of therapies and opens the door to the evaluation of this approach in different kinds of solid tumors.

lncmtRNA long noncoding mitochondrial ribonucleic acid

SncmtRNA sense noncoding mitochondrial ribonucleic acid

ASncmtRNA antisense noncoding mitochondrial ribonucleic acid

Jaime Villegas Olavarria1,2\*, Verónica A. Burzio1,2, Vincenzo Borgna1,3,

, Francisca Guevara1

Long Noncoding Mitochondrial RNAs (LncmtRNAs) as Targets for Cancer Therapy

4 Centro de Medicina Regenerativa, Facultad de Medicina, Clínica Alemana Universidad del

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[2] Giampazolias E, Tait S. Mitochondria and the hallmarks of cancer. The FEBS Journal.

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[4] Ishikawa K, Takenaga K, Akimoto M, Koshikawa N, Yamaguchi A, Imanishi H, Nakada K, Honma Y, Hayashi J. ROS-generating mitochondrial DNA mutations can regulate tumor

[5] Porporato P, Payen V, Perez-Escuredo J, De Saedeleer C, Danhier P, Copetti T, Dhup S, Tardy M, Vazeille T, Bouzin C, Feron O, Michiels C, Gallez B, Sonveaux P. A mitochondrial switch promotes tumor metastasis. Cell Reports. 2014;**8**:754-766. DOI: 10.1016/j.celrep.2014.06.043 [6] Seligmann H. Chimeric mitochondrial peptides from contiguous regular and swinger RNA. Computational and Structural Biotechnology Journal. 2016;**14**:283-297. DOI:

cell metastasis. Science. 2008;**320**:661-664. DOI: 10.1126/science.1156906

5 Departamento de Ciencias Químicas y Biológicas, Facultad de Salud, Universidad

, Claudio Villota1,5 and

http://dx.doi.org/10.5772/intechopen.75453

189

, Mariela Araya2

1 Facultad de Ciencias Biológicas, Universidad Andrés Bello, Chile

2 Andes Biotechnologies SpA – Fundación Ciencia para la Vida, Chile

Journal of Cancer. 2015;**112**:957-962. DOI: 10.1038/bjc.2015.85

\*Address all correspondence to: jvillegas@bioschile.cl

3 Facultad de Medicina, Universidad de Santiago, Chile

2016;**283**:803-814. DOI: 10.1111/febs.13603

ncRNA noncoding ribonucleic acid

**Author details**

Luis O. Burzio1,2

Desarrollo, Chile

**References**

Bernardo O'Higgins, Santiago, Chile

NEJMcibr1003521

10.1016/j.csbj.2016.06.005

Lorena Lobos-Gonzalez4

The mechanism by which interference of these RNAs generates cell death, apoptosis and delay in metastasis is beyond the scope of this review. However, our preliminary evidence indicates that the double strand region of the antisense RNAs is a seed for generation of miRNAs, which could target mRNAs of several proteins involved in cell cycle control, cell survival, invasion and metastasis. Therefore, knockdown of these RNAs generates a pleiotropic effect that affects simultaneously several important pathways necessary throughout the whole tumorigenic process.

Mitochondrial long noncoding RNAs are novel actors in cancer metabolism and understanding the roles they fulfill in tumor cell biology will make it possible to select in the future novel targets for the development of new therapies that could be effective and of low toxicity for patients. Our target described here meets these two requirements and at present is being evaluated in a Phase I protocol soon to finish. Those results will give the necessary data to continue with the next phase and to evaluate more in depth the efficacy of our therapy.
