Firefox, a protein encoded by circular PVT1, is essential for MYC-driven oncogenesis.

Tiwari A, Paithane U, Tashiro K, Hall B, Friedlein J, Saraswat M, Saulnier O, Barbosa K, Trinh Q, Saha S, Soni A, …, Bagchi A · 2026 · Genes & Development · Atlas ID TIW2026

What this study shows

A micropeptide (Firefox/FFX) encoded by the circular RNA circPVT1 stimulates AKT-mTORC1 signaling and cap-dependent translation to sustain MYC protein abundance and transcriptional output. FFX depletion reduces MYC levels and impairs tumor growth in MYC-amplified xenograft models, identifying an mTORC1-linked vulnerability in MYC-driven cancers.

At a glance

Evidence type	M Molecular — cells, biochemistry, structure Marked M because it is molecular or in-vitro work (model: Human MYC-amplified cancer cell lines; xenograft mouse models) rather than a whole-organism health-outcome study. That is often exactly where causal biology gets established -- the code says which system the finding was shown in, and nothing about how good the work is.
Study type	5 - Mechanistic / In Vitro
Model system	Human MYC-amplified cancer cell lines; xenograft mouse models
Journal	Genes & Development
Year	2026
Peer reviewed	Yes
Record last updated	2026-10-01
Source	DOI 10.1101/gad.353355.125 · PMID 42618323

Extracted findings

These fields were extracted from the paper with AI assistance and have not been checked against the source. Read them as a pointer into the paper, not as curated claims; where they disagree with the curated summary above, the curated summary stands.

Intervention	Depletion of the circPVT1-encoded micropeptide (FFX)
Target	AKT-mTORC1 signalling and cap-dependent translation, sustaining MYC
Model	Human MYC-amplified cancer cell lines; mouse xenografts
Effect	The micropeptide sustains AKT-mTORC1 signalling and cap-dependent translation; depleting it lowered MYC protein and impaired xenograft tumour growth.

In the Atlas

Cite this paper

ShowHide

Tiwari, A., Paithane, U., Tashiro, K., Hall, B., Friedlein, J., Saraswat, M., Saulnier, O., Barbosa, K., Trinh, Q., Saha, S., Soni, A., Nakashima, T., Murad, R., Maurya, S., Chapman, O. S., James, B., Erickson, A., Lange, J. T., Leary, R., Varshney, J., Konety, B., Dehm, S. M., Kawakami, Y., Largaespada, D. A., Weiss, W. A., Stein, L., Chavez, L., Suzuki, H., Wu, S., Zhao, J., Deshpande, A. J., Taylor, M. D., Wechsler-Reya, R. J., & Bagchi, A. (2026). Firefox, a protein encoded by circular PVT1, is essential for MYC-driven oncogenesis. Genes & Development. https://doi.org/10.1101/gad.353355.125

@article{TIW2026,
  author       = {Tiwari, A. and Paithane, U. and Tashiro, K. and Hall, B. and Friedlein, J. and Saraswat, M. and Saulnier, O. and Barbosa, K. and Trinh, Q. and Saha, S. and Soni, A. and Nakashima, T. and Murad, R. and Maurya, S. and Chapman, O. S. and James, B. and Erickson, A. and Lange, J. T. and Leary, R. and Varshney, J. and Konety, B. and Dehm, S. M. and Kawakami, Y. and Largaespada, D. A. and Weiss, W. A. and Stein, L. and Chavez, L. and Suzuki, H. and Wu, S. and Zhao, J. and Deshpande, A. J. and Taylor, M. D. and Wechsler-Reya, R. J. and Bagchi, A.},
  title        = {{Firefox, a protein encoded by circular PVT1, is essential for MYC-driven oncogenesis}},
  journal      = {Genes & Development},
  year         = {2026},
  doi          = {10.1101/gad.353355.125},
  note         = {PMID: 42618323},
}

Cite this Atlas record

The record is the Atlas's own work — the evidence label, the extracted findings and the links. It is cited as part of the dataset, not as the paper.

Barton, O. (2026). Oliver's mTOR Atlas (record TIW2026) [Data set]. https://mtor-atlas.org/study/TIW2026/ · Dataset DOI 10.5281/zenodo.22059963

@misc{atlas_TIW2026,
  author       = {Barton, Oliver},
  title        = {{Oliver's mTOR Atlas}, record TIW2026},
  howpublished = {Data set},
  year         = {2026},
  url          = {https://mtor-atlas.org/study/TIW2026/},
  doi          = {10.5281/zenodo.22059963}
}

Was this page useful?