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Biology subjects

Lorz, C.

Publications and source records attributed to Lorz, C..

3 recordsLinked to original sources

Active Liposomal Targeting for Head and Neck Squamous Cell Carcinoma Treatment

Head and neck squamous cell carcinoma (HNSCC) is a major oncological challenge due to its high recurrence rates, biological heterogeneity, and poor long-term survival outcomes. Despite advances in surgery and radiotherapy, chemotherapeutic options are limited. Cisplatin (CDDP) remains the mainstay, while small molecule inhibitors, such as the selective PI3K inhibitor Alpelisib, are still under clinical evaluation. However, systemic side effects and suboptimal tumor specificity hamper the clinical utility of both standard and novel specific therapies. In this study, we developed passive- and active-targeting liposomes encapsulating Cisplatin (CDDP) and Alpelisib. To achieve active targeting, the anti-epidermal growth factor receptor (EGFR) antibody Cetuximab was conjugated to the liposome surface. All formulations were characterized based on size, morphology, encapsulation efficiency, and drug release profiles. In vitro assays demonstrated that liposomal encapsulation preserved the cytotoxic effects of both CDDP and Alpelisib in HNSCC cell lines, with CDDP showing adequate encapsulation efficiency for in vivo evaluation. In vivo near-infrared fluorescence imaging demonstrated that active-targeting liposomes achieved greater tumor accumulation and a better tumor-to-spleen ratio compared to passive formulations. Tumor growth by CDDP-loaded activetargeting liposomes was comparable to that of the free drug, likely due to the hydrophilic nature and rapid release of CDDP from liposomes in physiological conditions. Importantly, blood chemistry analysis indicated a favorable toxicity profile for the targeted liposomal formulation. These findings highlight the potential of liposome-based targeted strategies to improve therapeutic outcomes in HNSCC and underscore the value of nanotechnology in the development of next-generation oncological therapies.

cancer biology↗

Fanca and p53 genes cooperate to suppress oral SCC in transgenic mice

Fanconi anemia (FA) patients frequently develop oral squamous cell carcinoma (OSCC). This cancer in FA patients is diagnosed within the first 3-4 decades of life, very often preceded by lesions that suffer a malignant transformation. In addition, they respond poorly to current treatments due to toxicity or multiple recurrences. Translational research of new chemopreventive agents and therapeutic strategies has been unsuccessful partly due to scarcity of disease models or failure to fully reproduce the disease. Here we report that Fanca gene knockout mice (Fanca-/-) frequently display pre-malignant lesions in the oral cavity. Moreover, when these animals were crossed with animals having conditional deletion of Trp53 gene in oral mucosa (K14cre;Trp53F2-10/F2-10), they spontaneously developed OSCC with a high penetrance and a median latency of less than ten months. Tumors were well differentiated and expressed markers of squamous differentiation, such as keratins K5 and K10. In conclusion, Fanca and Trp53 genes cooperate to suppress oral cancer in mice, and Fanca-/-;K14cre;Trp53F2-10/F2-10 mice constitute the first animal model of spontaneous OSCC in FA.

cancer biology↗

Generating new FANCA-deficient HNSCC cell lines by genomic editing recapitulate the cellular phenotypes of Fanconi anemia

Fanconi anemia (FA) patients have an exacerbated risk of head and neck squamous cell carcinoma (HNSCC). Treatment is challenging as FA patients display enhanced toxicity to standard treatments, including radio/chemotherapy. Therefore better therapies as well as new disease models are urgently needed. We have used CRISPR/Cas9 editing tools in order to interrupt the human FANCA gene by the generation of insertions/deletions (indels) in exon 4 in two cancer cell lines from sporadic HNSCC having no mutation in FA-genes: CAL27 and CAL33 cells. Our approach allowed efficient editing, subsequent purification of single-cell clones, and Sanger sequencing validation at the edited locus. Clones having frameshift indels in homozygosis did not express FANCA protein and were selected for further analysis. When compared with parental CAL27 and CAL33, FANCA-mutant cell clones displayed a FA-phenotype as they i) are highly sensitive to DNA interstrand crosslink (ICL) agents such as mitomycin C (MMC) or cisplatin, ii) do not monoubiquitinate FANCD2 upon MMC treatment and therefore iii) do not form FANCD2 nuclear foci, and iv) they display increased chromosome fragility and G2 arrest after diepoxybutane (DEB) treatment. These FANCA-mutant clones display similar growth rates as their parental cells. Interestingly, mutant cells acquire phenotypes associated with more aggressive disease, such as increased migration in wound healing assays. Therefore, CAL27 and CAL33 cells with FANCA mutations are phenocopies of FA-HNSCC cells.

cancer biology↗