Beyond Gap Junctions: Connexins as Orchestrators of Tumor–Stroma Communication
We are looking for an ambitious postdoctoral researcher to develop an independent Marie Skłodowska-Curie Fellowship project at the interface of cancer cell communication, metabolism, and tumor microenvironment biology.
Marie Skłodowska-Curie Actions – Postdoctoral Fellowships (MSCA-PF)
The Marie Skłodowska-Curie Postdoctoral Fellowships (MSCA-PF) are part of the Horizon Europe programme and support postdoctoral researchers in developing an original research and innovation project through international mobility.
The programme aims to strengthen researchers’ careers through excellent science, international collaboration and interdisciplinary experience, while fostering integration in both academic and non-academic environments. The MSCA-PF call is highly competitive and represents an excellent opportunity to attract international talent and support researchers in consolidating their scientific careers through an ambitious mobility-based fellowship.
The 2026 call closes on 09/09/2026 (17:00 Brussels time). For candidates applying to a European Postdoctoral Fellowship, the fellowship duration is from 12 to 24 months
Full eligibility details: MSCA Postdoctoral Fellowships 2026
Background
Connexin 43 (Cx43) presents a long-standing paradox in cancer: it can act as either a tumour suppressor or a tumour promoter depending on context. Beyond its classical role as a gap junction protein, Cx43 regulates tunnelling nanotube (TNT) formation, mitochondrial transfer, and extracellular vesicle (EV) signalling. Its alternatively translated isoform GJA1-20k further controls actin remodelling and mitochondrial dynamics, suggesting that connexins play a broader role in coordinating communication between tumour cells and their microenvironment.
This project will test the hypothesis that Cx43 acts as a master regulator of intercellular communication, linking these pathways to tumour plasticity and therapeutic resistance across breast, lung, and pancreatic cancer.
Objective
The aim is to define how connexin-regulated tumour-stroma communication drives cancer progression and therapy resistance. Possible research directions include: (1) how Cx43 and GJA1-20k regulate TNT formation and organelle transfer; (2) non-canonical mitochondrial exchange pathways including annular gap junctions; (3) Cx43 control of EV biogenesis and signalling; and (4) how these pathways collectively regulate metabolic adaptation and therapy resistance. The project will be developed together with the fellow based on their expertise and interests.
Our Group
The Intercellular Communication Group, led by Trond Aasen, studies connexin-regulated tumour progression, metastasis, and therapy resistance in breast, lung, and pancreatic cancer. We combine mechanistic cell biology with advanced imaging and functional cancer models. Recent tools include dual-colour HiBiT-based mitochondrial tracing systems for quantifying intercellular organelle transfer. This is a growing field with real room for discovery.
You will define your own questions, develop your own ideas, and build your scientific identity. Mentoring and support for the MSCA application are part of the deal, but scientific ownership is yours.
The fellow will have access to advanced live-cell and super-resolution imaging, cell engineering platforms, and well-established cancer models, as well as active collaborations with Marc Liesa (mitochondrial metabolism and redox biology) and Henrique Girão (EV biology and connexin signalling).
The goal is to provide the successful candidate with both scientific freedom and strong mentorship, supporting not only the MSCA application but also the longer-term transition toward research leadership.
Applicants must hold a PhD degree or have successfully defended their thesis before the call deadline (09/09/2026)
Applicants must comply with the mobility rule, meaning they must not have resided or carried out their main activity (work/studies) in the host country for more than 12 months during the 36 months prior to the call deadline.
Fluency in English
First author in publications
Passionate, proactive, willing to learn and committed
Desirable:
Strong publication record.
International research experience
Experience with fellowship writing is a plus
Applicants must have a maximum of 8 years of postdoctoral research experience by the call deadline. This means candidates are generally eligible if they obtained their PhD on or after 10/09/2018 (possible extensions may apply, e.g. parental leave or long-term illness).
Strong experimental background in mammalian cell biology
Experience in molecular cloning and cell engineering
Experience in one or more of the following:
Mitochondrial biology, cancer metabolism, extracellular vesicles, tunneling nanotubes, live-cell imaging, CRISPR editing, omics or bioinformatics. Experience in fluorescence microscopy/confocal imaging
Demonstrated ability to drive independent research
Strong written and oral communication skills
Deadline to apply: 31-07-2026
VHIR embraces Equality and Diversity. As reflected in our values we work toward ensuring inclusion and equal opportunity in recruitment, hiring, training, and management for all staff within the organisation, regardless of gender, civil status, family status, sexual orientation, gender identity and expression, religion, age, functional diversity or ethnicity.
Information on Personal Data Protection:
Data Controller: Fundació Hospital Universitari Vall d’Hebron Institut de Recerca -VHIR-. Purpose: Personnel selection. Legal Basis: Your consent. Data retention period: One year. If you are selected, as long as the employment relationship is in force and legal responsibilities may arise. Data sharing: Does not occur, except for communications necessary to fulfill the purpose and those required by law to public and private bodies. Rights: You can access, rectify, delete, object to, and limit the processing of data, as well as request data portability where applicable, by contacting lopd@vhir.org DPO: dpd@ticsalutsocial.cat More information can be found here
Data Protection Authority: APDCAT
We are a public sector institution that promotes and develops the biomedical research, innovation and teaching at Vall d'Hebron University Hospital, the hospital of Barcelona and the largest of Catalan Institute of Health (ICS). The members of our Board of Trustees are the Catalan Ministry of Health, the Catalan Ministry of Economy and Knowledge (we are a CERCA center), Vall d'Hebron University Hospital, Bank of blood and tissues, the Autonomous University of Barcelona (UAB), of which we are an accredited research institute, and the Vall d'Hebron Institute of Oncology (VHIO), which together with VHIR is part of Accredited Institute of Campus Vall d’Hebron Institute by the Institute of Health Carlos III (ISCIII).
Since its creation in 1994, VHIR works to find solutions to the health problems of society, and contribute to spread them around the world. In more than 20 years we have achieved leadership in biomedical research at hospitals in our country, and we want to be recognised in 2020 as an excellent and competitive European Institute leader in clinical and traslational research linked to a university hospital.
In our institute are working more than 1,300 people, of which over 1,200 doing research and others, around 100, help to do it or transfer it to the society once made, whether in the form of projects, technology transfer and innovation, communication or fundraising, among others.
The best of our institution and its research staff is doing research to solve people’s health problems. Our task is not only basic or translational, we are leaders in clinical research. We have the beds of the hospital separated in less than 50 meters of laboratories and our patients will benefit from our research. In this we believe, and our efforts are focused on it. This is understood by industry leaders who are committed to our hospital, making it a world reference for its first clinical trials.
