In animal experiments, Hungarian researchers successfully inhibited the growth of skin and lung cancers, and achieved complete remission in breast cancer. The joint development of the HUN-REN Centre for Natural Sciences (HUN-REN TTK) and Eötvös Loránd University (ELTE) may open a new chapter in anti-tumour therapies. Their results have been published in the prestigious international journal Molecular Cancer.

In their recently published study, the researchers demonstrated how they managed to “tame” a highly toxic anti-cancer agent, pyrrolino-daunorubicin, by enclosing it in a liposomal nanocarrier.
The resulting compound — liposomal pyrrolino-daunorubicin (LiPyDau) — displayed unprecedented efficacy that even surprised the research team.

In animal experiments, LiPyDau inhibited tumour growth in six different tumour models — including melanoma and lung cancer — and, remarkably, achieved complete recovery in a hereditary breast cancer model.
A key finding is that LiPyDau

was also effective against drug-resistant tumours,

which no longer respond to conventional clinical treatments.

Within just one week after a single administration, LiPyDau completely eradicated one of the most resistant mouse breast tumours derived from the 4T1 cell line. Using luminescent imaging, researchers could precisely track the size and location of tumours. Photo: Dr Kata Bölcskei, Institute of Pharmacology and Pharmacotherapy, University of Pécs.

The Result of a Decade of Research

The synthesis of the compound was carried out under the leadership of Gábor Mező at the HUN-REN–ELTE Peptide Chemistry Research Group of the ELTE Faculty of Science.
According to Kristóf Hegedüs (formerly ELTE, currently HUN-REN TTK), once they realised the potential of the molecule, the team focused on developing production methods that would ensure high quality and sufficient quantity for animal testing.

The group had to cover a broad chemical spectrum before developing a stable production method. Krisztina Kiss(ELTE TTK) investigated the compound’s stability and behaviour under physiological and biologically relevant conditions, paving the way for subsequent cell-culture studies. These results provided a strong foundation for the liposomal formulation described in the study and may also inform future applications against other tumour types.

Pyrrolino-daunorubicin is known to be roughly a thousand times more toxic to cancer cells than traditional anti-cancer drugs.
The major challenge was how to deliver it safely — without harming healthy tissues.
“That’s when the idea of liposomal encapsulation emerged,” said Szilárd Tóth, who led the cell-line testing.
“This method shields healthy cells from the active compound while enabling selective accumulation in tumours. This is how LiPyDau was born.”

According to the study’s first author, András Füredi, LiPyDau is not only effective, but based on current data and literature, one of the most powerful anti-tumour compounds ever tested in mice.
“We have been working on tumour therapies for fifteen years, but we have never seen such a strong effect.

A single dose of LiPyDau cured the experimental animals,”

he emphasized.

The breakthrough was the result of a broad collaboration within HUN-REN TTK. In addition to the group of Dr Gergely Szakács, the research teams led by Dr Zoltán Varga, Dr Pál Szabó, and Dr Dávid Szüts played indispensable roles in the development and testing of LiPyDau, while Dr Csaba Magyar conducted the in silico molecular modelling.
These groups have worked together closely for nearly ten years.

A Hungarian Success Built on Cooperation

Gergely Szakács, head of the research, emphasized the exemplary cooperation among Hungarian institutions.
The project involved HUN-REN TTK, ELTE TTK, the National Institute for Pharmaceutical Development, the HUN-REN Energy Research Centre, Óbuda University, the University of Pécs, the National Institute of Oncology, and the University of Veterinary Medicine Vienna. The research was also supported by Kineto Lab Ltd., one of Hungary’s leading oncology-development companies. Together with the academic partners, they are already planning the next steps toward clinical testing of LiPyDau.
However, further pre-clinical studies are required before human application can begin.

The aim is clinical trials

When asked about the potential clinical translation of the compound, Attila Kigyós, founding director of Kineto Lab Ltd., stated: “LiPyDau is by far the most effective anti-tumour compound we have ever tested in the company’s history.
We must do everything possible to advance it to the stage of clinical trials — or attract a major pharmaceutical partner to continue development into a marketed oncology drug.” According to the researchers, LiPyDau has a strong potential to become a Hungarian-developed cancer therapy.

Source: HUN-REN, ELTE Institute of Chemistry