Introduction:
In Colombia, the cancer burden and territorial inequities in access to timely and effective interventions represent a major public health challenge. In this context, the National Cancer Institute of Colombia (Instituto Nacional de Cancerología, INC), an institution affiliated with and advisory to the Ministry of Health and Social Protection, plays a strategic role in knowledge generation and management, as well as in the promotion of scientific and technological research in cancer.
As the coordinating body of the National Cancer Research Network (Red Nacional de Investigación en Cáncer, RNIC), the INC fosters the articulation of academic, healthcare, scientific, social, and governmental institutions to integrate capacities, strengthen interinstitutional collaboration, and consolidate science, technology, and innovation ecosystems oriented toward comprehensive cancer control and the reduction of inequities. Promoting collaborative work from the formulation of ideas addressing high-impact missions and challenges enables researchers to join efforts to overcome critical gaps in this field.

Objective:
To describe the experience of a co-created call for proposals led by the RNIC as a strategy to translate cancer research into public health action and to strengthen national capacities through collaborative projects aimed at reducing inequities.

Methods:
The RNIC designed and implemented an extramural call for proposals under a participatory approach, guided by a national transformative mission: the elimination of cancer inequities. The process included an open call to network members, review and preselection of proposals based on criteria of relevance, impact, feasibility, and capacity strengthening, and the organization of an in-person co-creation workshop. This workshop promoted knowledge exchange, integration of multidisciplinary perspectives, and collective solution-building, with an emphasis on interinstitutional collaboration and the development of scientific and management capacities.

Results:
Ten proposals were submitted, of which eight met the established eligibility criteria. Following the preselection process, three proposals advanced to a co-creation workshop facilitated using the LEGO® Serious Play® methodology. This structured space for collective reflection enabled the construction of three-dimensional models and shared narratives, through which researchers from different disciplines conducted a systemic analysis of challenges related to reducing cancer inequities. Participants strengthened their conceptual and methodological approaches, aligned their objectives with the prioritized transformative mission, and consolidated strategic alliances between academic and healthcare institutions. As a result of this process, one proposal led by the Corporación Salud UN – Hospital Universitario Nacional de Colombia was selected and continued the co-creation process until the final project was consolidated.

Conclusions:
The experience of the RNIC co-created call for proposals demonstrates the value of national research networks as platforms for capacity-building in middle-income countries. This participatory model enhances relevance, interinstitutional collaboration, and the development of mission-oriented projects, offering transferable lessons for other contexts seeking to reduce inequities and maximize the public health impact of cancer research.