No abstract

Background Ferritin receptor (CD71) is an example of a very attractive cancer target, since it is highly expressed in virtually all tumor types, including metastatic loci. However, this target can be considered to be inaccessible to conventional target therapies, due to its presence in many healthy tissues. Here, we describe the preclinical evaluation of a tumor proteases-activatable human ferritin (HFt)-based drug carrier (The-0504) that is able to selectively deliver the wide-spectrum topoisomerase I inhibitor Genz-644282 to CD71-expressing tumors, preventing the limiting toxic effects associated with CD71-targeting therapies. Methods CD71 expression was evaluated using flow cytometry and immunohistochemistry techniques. The-0504 antiproliferative activity towards several cancer cell lines was assessed in vitro. The-0504 antitumor efficacy and survival benefit were evaluated in different human tumors, which had been grown either as xenografts or patient-derived xenografts in mice. The-0504 toxicology profile was investigated in multiple-cycle repeat-dose study in rodents. Results In vitro studies indicate that The-0504 is highly specific for CD71 expressing cells, and that there is a relationship between CD71 levels and The-0504 anticancer activity. In vivo treatments with The-0504 showed a remarkable efficacy, eradicating several human tumors of very diverse and aggressive histotypes, such as pancreas, liver and colorectal carcinomas, and triple-negative breast cancer. Conclusions Durable disease-free survival, persistent antitumor responses after discontinuation of treatment and favorable toxicology profile make The-0504 an ideal candidate for clinical development as a novel, CD71-targeted, low-toxicity alternative to chemotherapy.

Gastrointestinal tumors, including pancreatic and colorectal cancers, represent one of the greatest public health issues worldwide, leading to a million global deaths. Recent research demonstrated that the human heavy chain ferritin (HFt) can encapsulate different types of drugs in its cavity and can bind to its receptor, CD71, in several solid and hematological tumors, thus highlighting the potential use of ferritin for tumor-targeting therapies. Here, we describe the development and characterization of a novel nanomedicine based on the HFt that is named The-0504. In particular, this novel system is a nano-assembly comprising an engineered version of HFt that entraps about 80 molecules of a potent, wide-spectrum, non-camptothecin topoisomerase I inhibitor (Genz-644282). The-0504 can be produced by a standardized pre-industrial process as a pure and homogeneously formulated product with favourable lyophilization properties. The preliminary anticancer activity was evaluated in cultured cancer cells and in a mouse model of pancreatic cancer. Overall results reported here make The-0504 a candidate for further preclinical development against CD-71 expressing deadly tumors.

COVID-19 pandemic has hit people’s health, economy, and society worldwide. Great confidence in returning to normality has been placed in the vaccination campaign. The knowledge of individual immune profiles and the time required to achieve immunological protection is crucial to choose the best vaccination strategy. We compared anti-S1 antibody levels produced over time by BNT162b2 and AZD1222 vaccines and evaluated the induction of antigen-specific T-cells. A total of 2569 anti-SARS-CoV-2 IgG determination on dried blood spot samples were carried out, firstly in a cohort of 1181 individuals at random time-points, and subsequently, in an independent cohort of 88 vaccinated subjects, up to the seventeenth week from the first dose administration. Spike-specific T-cells were analysed in seronegative subjects between the two doses. AZD1222 induced lower anti-S1 IgG levels as compared to BNT162b2. Moreover, 40% of AZD1222 vaccinated subjects and 3% of BNT162b2 individuals resulted in seronegative during all the time-points, between the two doses. All these subjects developed antigen-specific T cells, already after the first dose. These results suggest that this test represents an excellent tool for a wide sero-surveillance. Both vaccines induce a favourable immune profile guaranteeing efficacy against severe adverse effects of SARS-CoV-2 infection, already after the first dose administration.

Doxorubicin is employed alone or in combination for the treatment of several hematological and solid malignancies; despite its efficacy, there are associated cardiotoxicity limits both in its application in patients with heart disease risk factors and also in its long-term use. HFt-MP-PAS40 is a genetically engineered human ferritin heavy chain (HFt)-based construct able to efficiently entrap and deliver doxorubicin to cancer cells. HF-MP-PAS contains a short motif sequence (defined as MP) responsive to proteolytic cleavage by tumor matrix metalloproteases (MMPs), located between each HFt subunit and a masking polypeptide sequence rich in proline (P), alanine (A), and serine (S) residues (PAS). This carrier displayed excellent therapeutic efficacy in a xenogenic pancreatic cancer model in vivo, leading to a significant increase in overall animal survival in treated mice. Herein, we describe the HFt-MP-PAS40-Dox efficacy against squamous cell carcinomas of the head and neck (HNSCC) with the goal of validating the application of our nano-drug for the treatment of different solid tumors. In addition, a tolerability study in healthy mice was also performed. The results indicate that HFt-MP-PAS40-Dox produced increased anti-tumor effects both in vitro and in vivo in comparison to the free drug in several HNSCC cell lines. In the acute toxicity studies, the maximum tolerated dose (MTD) of HFt-MP-PAS40-Dox was about 3.5 higher than the free drug: 25 mg/kg versus 7 mg/kg doxorubicin equivalents. Importantly, evaluation of heart tissues provided evidence that doxorubicin is less cardio-toxic when encapsulated inside the ferritin carrier. In conclusion, HFt-MP-PAS40-Dox may be administered safely at higher doses compared with the free drug, resulting in superior efficacy to control HNSCC malignancies.