Synaptic Vesicle Protein 2 and Vesicular Monoamine Transporter 1 and 2 Are Expressed in Neuroblastoma

Synaptic vesicle protein 2-targeted doxorubicin-loaded liposome for effective neuroblastoma therapy

Neuroblastoma, a pediatric cancer originating from neural crest tissues of the sympathetic nervous system, poses significant treatment challenges due to its molecular diversity and restricted druggable targets. While chemotherapy is a common treatment, its drawbacks, including poor targeting of cancer cells and nonspecific cytotoxicity, highlight the urgent need for innovative and effective therapeutic strategies. Herein, we developed a novel drug by coupling the receptor binding domain of botulinum neurotoxin type A (Hc) fused with monomeric streptavidin (mSA) to biotin coated doxorubicin (Dox)-loaded liposome, via interaction between mSA and biotin. The resultant Hc-coated liposome (Hc-Lipo@Dox) actively targeted the recycling synaptic vesicle 2 protein (SV2) abundantly expressed on the surface of neuroblastoma cells. Our results revealed that Hc-Lipo@Dox more effectively entered the neuroblastoma SH-SY5Y cells, inducing apoptosis compared to non-targeted liposome and free Dox. Moreover, Hc-Lipo@Dox rapidly enriched Dox in the subcutaneously implanted neuroblastoma tumor in nude mice, resulting potent anti-neuroblastoma effect compared to non-targeted liposomes or free Dox. Importantly, Hc-Lipo@Dox significantly improved the survival rate of treated mice, while also exhibiting a favorable safety profile with no discernible impact on mobility or observable side effects. These findings highlight the potential of SV2-targeted Dox liposome as a promising and well-tolerated chemotherapy approach for neuroblastoma treatment. Moreover, the technology established here has broader applications for various cancer therapies by substituting the Hc moiety with other tumor-specific targeting moieties.

GMP-compliant automated radiosynthesis of [18F] SynVesT-1 for PET imaging of synaptic vesicle glycoprotein 2 A (SV2A)

BACKGROUND

A novel positron emission tomography (PET) imaging tracer, [18F] SynVesT-1, targeting synaptic vesicle glycoprotein 2 (SV2A), has been developed to meet clinical demand. Utilizing the Trasis AllinOne-36 (AIO) module, we've automated synthesis to Good Manufacturing Practice (GMP) standards, ensuring sterile, pyrogen-free production. The fully GMP-compliant robust synthesis of [18F] SynVesT-1 boosting reliability and introducing a significant degree of simplicity and its comprehensive validation for routine human use.

RESULTS

[18F] SynVesT-1 was synthesized by small modifications to the original [18F] SynVesT-1 synthesis protocol to better fit AIO module using an in-house designed cassette and sequence. With a relatively small precursor load of 5 mg, [18F] SynVesT-1 was obtained with consistently high radiochemical yields (RCY) of 20.6 ± 1.2% (the decay-corrected RCY, n = 3) at end of synthesis. Each of the final formulated batches demonstrated radiochemical purity (RCP) and enantiomeric purity surpassing 99%. The entire synthesis process was completed within a timeframe of 80 min (75 ± 3.1 min, n = 3), saves 11 min compared to reported GMP automated synthesis procedures. The in-human PET imaging of total body PET/CT and time-of-flight (TOF) PET/MR showed that [18F] SynVesT-1 is an excellent tracer for SV2A. It is advantageous for decentralized promotion and application in multi-center studies.

CONCLUSION

The use of AIO synthesizer maintains high production yields and increases reliability, reduces production time and allows rapid training of production staff. Besides, the as-prepared [18F] SynVesT-1 displays excellent in vivo binding properties in humans and holds great potential for the imaging and quantification of synaptic density in vivo.

Neurotransmitter release cycle-related genes predict the prognosis of lung adenocarcinoma

Because of the limitations of therapeutic approaches, patients suffering from lung adenocarcinoma (LUAD) have unsatisfactory prognoses. Studies have shown that neurotransmitters participated in tumorigenesis and development. In LUAD, the expression of neurotransmitter release cycle-related genes (NRCRGs) has been reported to be disordered. This study aimed to study the correlation between NRCRGs and LUAD. In this study, based on the Cancer Genome Atlas cohort, consensus clustering analyses were performed on ten neurotransmitter release cycle-related (NRCR) differentially expressed genes. Neurotransmitter release cycle (NRC) scores were derived by the Least Absolute Shrinkage and Selection Operator-Cox regression model constituted by 3 NRCRGs. Univariate and multivariate Cox regression analyses were performed to evaluate the prognosis value of the NRC score. In addition, single-Sample Gene Set Enrichment Analysis and CIBERSORT were conducted in the Cancer Genome Atlas cohort. Finally, gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses were also performed. As a result, the NRC-low group showed a good prognosis instead of the NRC-high group. NRC score was identified to be an independent prognosis factor for LUAD. In general, the NRC score based on the prognostic model was found to be closely correlated with immunotherapy-related anti-cancer immunity and inflamed tumor microenvironment. Functional enrichment results demonstrated that differentially expressed genes between 2 NRC groups were closely correlated with DNA replication, cell-substrate adhesion, Golgi vesicle transport, MAPK signal pathway, and many others. Novel biomarkers were offered for predicting the prognoses of LUAD patients. The NRC score might contribute to guiding LUAD patients with immunotherapy selection.

Validation of SV2A-Targeted PET Imaging for Noninvasive Assessment of Neuroendocrine Differentiation in Prostate Cancer

Neuroendocrine prostate cancer (NEPC) is an aggressive and lethal variant of prostate cancer (PCa), and it remains a diagnostic challenge. Herein we report our findings of using synaptic vesicle glycoprotein 2 isoform A (SV2A) as a promising marker for positron emission tomography (PET) imaging of neuroendocrine differentiation (NED). The bioinformatic analyses revealed an amplified SV2A gene expression in clinical samples of NEPC versus castration-resistant PCa with adenocarcinoma characteristics (CRPC-Adeno). Importantly, significantly upregulated SV2A protein levels were found in both NEPC cell lines and tumor tissues. PET imaging studies were carried out in NEPC xenograft models with ¹⁸F-SynVesT-1. Although ¹⁸F-SynVesT-1 is not a cancer imaging agent, it showed a significant uptake level in the SV2A⁺ tumor (NCI-H660: 0.70 ± 0.14 %ID/g at 50–60 min p.i.). The SV2A blockade resulted in a significant reduction of tumor uptake (0.25 ± 0.03 %ID/g, p = 0.025), indicating the desired SV2A imaging specificity. Moreover, the comparative PET imaging study showed that the DU145 tumors could be clearly visualized by ¹⁸F-SynVesT-1 but not ⁶⁸Ga-PSMA-11 nor ⁶⁸Ga-DOTATATE, further validating the role of SV2A-targeted imaging for noninvasive assessment of NED in PCa. In conclusion, we demonstrated that SV2A, highly expressed in NEPC, can serve as a promising target for noninvasive imaging evaluation of NED.

Bombesin Receptor Family Activation and CNS/Neural Tumors: Review of Evidence Supporting Possible Role for Novel Targeted Therapy

G-protein-coupled receptors (GPCRs) are increasingly being considered as possible therapeutic targets in cancers. Activation of GPCR on tumors can have prominent growth effects, and GPCRs are frequently over-/ectopically expressed on tumors and thus can be used for targeted therapy. CNS/neural tumors are receiving increasing attention using this approach. Gliomas are the most frequent primary malignant brain/CNS tumor with glioblastoma having a 10-year survival <1%; neuroblastomas are the most common extracranial solid tumor in children with long-term survival<40%, and medulloblastomas are less common, but one subgroup has a 5-year survival <60%. Thus, there is an increased need for more effective treatments of these tumors. The Bombesin-receptor family (BnRs) is one of the GPCRs that are most frequently over/ectopically expressed by common tumors and is receiving particular attention as a possible therapeutic target in several tumors, particularly in prostate, breast, and lung cancer. We review in this paper evidence suggesting why a similar approach in some CNS/neural tumors (gliomas, neuroblastomas, medulloblastomas) should also be considered.