An AAV gene therapy computes over multiple cellular inputs to enable precise targeting of multifocal hepatocellular carcinoma in mice

Synthetic biology approaches for improving the specificity and efficacy of cancer immunotherapy

Immunotherapy has shown robust efficacy in treating a broad spectrum of hematological and solid cancers. Despite the transformative impact of immunotherapy on cancer treatment, several outstanding challenges remain. These challenges include on-target off-tumor toxicity, systemic toxicity, and the complexity of achieving potent and sustainable therapeutic efficacy. Synthetic biology has emerged as a promising approach to overcome these obstacles, offering innovative tools for engineering living cells with customized functions. This review provides an overview of the current landscape and future prospects of cancer immunotherapy, particularly emphasizing the role of synthetic biology in augmenting its specificity, controllability, and efficacy. We delineate and discuss two principal synthetic biology strategies: those targeting tumor surface antigens with engineered immune cells and those detecting intratumoral disease signatures with engineered gene circuits. This review concludes with a forward-looking perspective on the enduring challenges in cancer immunotherapy and the potential breakthroughs that synthetic biology may contribute to the field.

scRNAseq and High-Throughput Spatial Analysis of Tumor and Normal Microenvironment in Solid Tumors Reveal a Possible Origin of Circulating Tumor Hybrid Cells

Metastatic cancer is a leading cause of death in cancer patients worldwide. While circulating hybrid cells (CHCs) are implicated in metastatic spread, studies documenting their tissue origin remain sparse, with limited candidate approaches using one-two markers. Utilizing high-throughput single-cell and spatial transcriptomics, we identified tumor hybrid cells (THCs) co-expressing epithelial and macrophage markers and expressing a distinct transcriptome. Rarely, normal tissue showed these cells (NHCs), but their transcriptome was easily distinguishable from THCs. THCs with unique transcriptomes were observed in breast and colon cancers, suggesting this to be a generalizable phenomenon across cancer types. This study establishes a framework for HC identification in large datasets, providing compelling evidence for their tissue residence and offering comprehensive transcriptomic characterization. Furthermore, it sheds light on their differential function and identifies pathways that could explain their newly acquired invasive capabilities. THCs should be considered as potential therapeutic targets.

Gene delivery to breast cancer by incorporated EpCAM targeted DARPins into AAV2

OBJECTIVE

The aim of this study is to evaluate an AAV vector that can selectively target breast cancer cells and to investigate its specificity and anti-tumor effects on breast cancer cells both in vitro and in vivo, offering a new therapeutic approach for the treatment of EpCAM-positive breast cancer.

METHODS

In this study, a modified AAV2 viral vector was used, in which EpCAM-specific DARPin EC1 was fused to the VP2 protein of AAV2, creating a viral vector that can target breast cancer cells. The targeting ability and anti-tumor effects of this viral vector were evaluated through in vitro and in vivo experiments.

RESULTS

The experimental results showed that the AAV2MEC1 virus could specifically infect EpCAM-positive breast cancer cells and accurately deliver the suicide gene HSV-TK to tumor tissue in mice, significantly inhibiting tumor growth. Compared to the traditional AAV2 viral vector, the AAV2MEC1 virus exhibited reduced accumulation in liver tissue and had no impact on tumor growth.

CONCLUSION

This study demonstrates that AAV2MEC1 is a gene delivery vector capable of targeting breast cancer cells and achieving selective targeting in mice. The findings offer a potential gene delivery system and strategies for gene therapy targeting EpCAM-positive breast cancer and other tumor types.

Rational design of microRNA-responsive switch for programmable translational control in mammalian cells

Artificial RNA translation modulation usually relies on multiple components, such as RNA binding proteins (RBPs) or microRNAs (miRNAs) for off-switches and double-inverter cascades for on-switches. Recently, translational circular RNAs (circRNAs) were developed as promising alternatives for linear messenger RNAs (mRNAs). However, circRNAs still lack straightforward and programmable translation control strategies. Here, we rationally design a programmable miRNA-responsive internal ribosome entry site (IRES) translation activation and repression (PROMITAR) platform capable of implementing miRNA-based translation upregulation and downregulation in a single RNA construct. Based on the PROMITAR platform, we construct logic gates and cell-type classifier circRNAs and successfully identify desired mammalian cell types. We also demonstrate the potential therapeutic application of our platform for targeted cancer cell killing by encoding a cytotoxic protein in our engineered circRNAs. We expect our platform to expand the toolbox for RNA synthetic biology and provide an approach for potential biomedical applications in the future.

Improved anti-hepatocellular carcinoma effect by enhanced Co-delivery of Tim-3 siRNA and sorafenib via multiple pH triggered drug-eluting nanoparticles

Effective systemic treatment for hepatocellular carcinoma (HCC) remains urgently needed. Sorafenib is the first FDA-approved systemic treatment for HCC. However, individual HCC patents’ response to sorafenib varies greatly. How to enhance the anti-HCC effect of sorafenib is still a significant challenge. T cell immunoglobulin mucin-3 (Tim-3) is a newly identified immune checkpoint molecule and a promising target for HCC treatment. Herein, we developed a novel pH-triggered drug-eluting nanoparticle (CC@SR&SF@PP) for simultaneously delivery of Tim-3 siRNA and sorafenib to HCC in situ. By a single emulsification method, a representative HCC targeted-therapeutic drug sorafenib (SF) was encapsulated into the pH-triggered positive-charged mPEG5K-PAE10K (PP) nanoparticles, followed by condensing of negative-charged Tim-3 siRNA. Then, carboxymethyl chitosan (CMCS), an amphoteric polysaccharide with negative charge in the physiological pH and positive charge in the acidic environment of the tumor, was eventually adsorbed onto the surface of nanoparticles. This co-delivery nanoparticle rapidly and specifically accumulated in the tumor site of the liver and enhanced the targeted, specific and multiple release of siRNA and sorafenib. Enhanced Tim-3 siRNA transfected into tumor cells can not only directly inhibit the growth of tumor cells by knock down the expression Tim-3, but also induce the immune response and enhance the recruitment of cytotoxic T cells to kill tumor cells. The following pH-triggered sorafenib release from SF@PP NPs greatly inhibited the tumor proliferation and angiogenesis, resulting in remarkable tumor growth inhibition in a mouse hepatoma 22 (H22) orthotopic tumor model. Thus, co-delivery of Tim-3 siRNA and sorafenib via this novel pH triggered drug-eluting nanoparticle enhances their anti-tumor efficacy. We expect that such combination treatment strategy will have great potential in future clinical applications.