Harnessing Gene Expression Prediction to Design Highly Efficient Oncolytic Viruses for Cancer Therapy

Freedom Preetham
Meta Multiomics
Published in
7 min readJun 27, 2023

Cancer continues to pose a significant threat to global health, urging researchers to push boundaries in developing innovative treatment modalities. One promising frontier in cancer therapy revolves around oncolytic viruses. These are unique viruses designed or naturally inclined to infect and destroy cancer cells while leaving normal cells unharmed.

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What are Oncolytic Viruses?

Oncolytic viruses are a type of virus that can selectively infect and destroy cancer cells while sparing healthy cells. They have been engineered or selected to replicate within tumor cells, causing their death or enabling the immune system to recognize and eliminate them.

The concept of using viruses to treat cancer is based on the observation that some viruses naturally have the ability to infect and kill cancer cells. Oncolytic viruses can be either naturally occurring or modified in the laboratory to improve their tumor-targeting capabilities and reduce their toxicity.

When administered to a patient, oncolytic viruses can specifically target cancer cells because of the unique characteristics of the tumor microenvironment. Tumor cells often have genetic abnormalities and defects in their antiviral defense mechanisms, making them more susceptible to viral infection. Additionally, tumors can provide an environment that promotes viral replication and spread.

Oncolytic viruses offer a unique approach to cancer treatment. They exploit the vulnerabilities of cancer cells and their altered pathways for replication, ultimately leading to cell death. This can occur naturally or be enhanced by genetic modification to increase the virus’s specificity towards cancer cells, minimize harm to normal cells, and stimulate an anti-tumor immune response.

The resultant cell death releases tumor antigens, which are then recognized by the patient’s immune system, sparking an immune response against the tumor. Oncolytic viruses can also be engineered to carry additional therapeutic genes, like immune-stimulating factors, to enhance their effectiveness.

Types of Oncolytic Viruses

There are a number of different types of oncolytic viruses that are being developed. Some of the most common types of oncolytic viruses include:

  • Adenoviruses: Adenoviruses are a type of DNA virus that can infect a wide range of tissues. They have been extensively studied for their oncolytic properties. Adenoviruses can be modified to selectively replicate within cancer cells and induce their destruction.
  • Herpes Simplex Viruses (HSV): Herpes simplex viruses, particularly HSV-1, have been engineered as oncolytic viruses. These viruses can infect and replicate within cancer cells, leading to cell death. HSV oncolytic viruses have shown promise in treating various cancers, including melanoma and glioblastoma.
  • Vaccinia Virus: Vaccinia virus is a DNA virus that was historically used as a smallpox vaccine. Modified versions of vaccinia virus have been developed as oncolytic viruses. They have demonstrated the ability to selectively target and destroy cancer cells.
  • Measles Virus: Measles virus, a member of the paramyxovirus family, has been explored as an oncolytic virus. It has shown oncolytic activity against different types of tumors, including ovarian, breast, and glioblastoma.
  • Reovirus: Reovirus is a double-stranded RNA virus that has been found to preferentially replicate in and kill cancer cells with specific mutations. It has been investigated in clinical trials for various types of cancers, such as colorectal cancer and head and neck cancer.
  • Newcastle Disease Virus (NDV): Newcastle disease virus is an avian paramyxovirus that has shown oncolytic potential. It can selectively target and kill cancer cells while sparing normal cells. NDV-based oncolytic therapies have been tested in clinical trials for several types of cancers.
  • Picornavirus: A family of small, non-enveloped RNA viruses that can cause a range of diseases in mammals and birds. The coxsackie virus is an example from this family that is being clinically tested for the treatment of cancer.
  • Maraba virus: a member of the Rhabdoviridae family, is an oncolytic virus with potential in cancer therapy. It has shown promise in selectively infecting and destroying cancer cells while sparing normal cells. Research efforts are focused on optimizing the therapeutic efficacy of Maraba virus for various types of cancer.
  • Vesicular stomatitis virus (VSV): A non-enveloped RNA virus causing animal vesicular lesions. In humans, it induces flu-like symptoms. As an oncolytic virus, VSV is explored for selectively targeting cancer cells, offering potential in cancer treatment. Clinical trials aim to optimize its efficacy.

Designing Oncolytic Viruses using Gene Expression Prediction

In designing oncolytic viruses, researchers often want the virus to express specific genes once it infects a cancer cell. This is where gene expression prediction comes in. Gene expression prediction is an exciting scientific approach that leverages computational and statistical techniques to anticipate the level of gene activity in specific biological situations.

1. Selection and Optimization of Transgene Expression:

The choice of promoter, a DNA segment responsible for initiating gene transcription, is crucial in controlling the expression level of the therapeutic gene. For instance, certain promoters might only activate in the presence of specific cancer markers, ensuring that the therapeutic gene is expressed primarily in cancer cells. By predicting how different promoters function in the viral context, researchers can select the most effective ones for their purpose.

In addition, gene expression prediction helps to optimize the level of therapeutic gene expression. Getting the ‘dose’ right is critical — too little expression, and the gene might not exert its intended effect; too much, and it might trigger unwanted side effects.

2. Spatial and Temporal Control:

Predicting gene expression also allows for spatial and temporal control of transgene activity. This implies the control over where and when the therapeutic gene is expressed. For instance, a gene that boosts immune response might be designed to activate only after the virus has entered a cancer cell, preventing unnecessary activation of the immune system in healthy tissues.

3. Safety and Efficacy Assessment:

Safety is a paramount concern in any form of therapy. Gene expression prediction can help anticipate whether a virus might express unwanted genes along with the therapeutic gene. It also assists in modeling the therapeutic outcomes, leading to improved viral designs.

Putting Theory into Practice: Real-World Examples

A compelling illustration of these concepts in action is the design of T-VEC (talimogene laherparepvec), an FDA-approved oncolytic virus for the treatment of advanced melanoma. T-VEC is a genetically modified herpes simplex virus designed to replicate within tumors and produce an immune-stimulatory protein called GM-CSF. Prediction and optimization of GM-CSF expression were key aspects of T-VEC’s design.

Another example is the use of oncolytic measles viruses engineered to express immune-modulating cytokines like interleukin-12, enhancing the anti-tumor immune response in preclinical models of ovarian cancer.

Generative AI based Onclyitic Virus Design

The use of generative artificial intelligence (AI) based gene expression prediction holds great potential for designing better oncolytic viruses. By leveraging the power of AI algorithms, researchers can gain insights into the complex interactions between viral genomes and host cells, leading to the development of more effective and targeted oncolytic viral therapies.

One of the challenges in oncolytic virotherapy is ensuring that the engineered viruses effectively replicate within cancer cells while minimizing their impact on healthy tissues. Generative AI techniques, such as deep learning and machine learning, can analyze vast amounts of genomic and transcriptomic data to identify patterns and predict gene expression profiles in different cellular contexts.

By training AI models on large datasets containing information about viral genomes, cancer cell characteristics, and host interactions, researchers can generate predictions about how specific modifications to viral genomes might impact viral replication and anti-tumor effects. This approach can facilitate the design of oncolytic viruses with enhanced tumor selectivity, improved replication dynamics, and augmented therapeutic potency.

Generative AI models can also aid in identifying genetic features that are associated with tumor susceptibility or resistance to viral infection. By analyzing gene expression profiles from tumor samples, AI algorithms can pinpoint molecular signatures that correlate with favorable treatment outcomes or identify potential biomarkers for patient stratification.

AI-based gene expression prediction can accelerate the optimization of oncolytic viruses by enabling researchers to simulate and predict the effects of different genetic modifications. This computational modeling approach can save time and resources by narrowing down the most promising candidates for further experimental validation.

Additionally, generative AI can contribute to the discovery of novel combinations of oncolytic viruses with other therapeutic modalities, such as immune checkpoint inhibitors or chemotherapeutic agents. By analyzing large-scale genomic and transcriptomic data, AI algorithms can identify potential synergistic effects and guide the development of combinatorial treatment strategies.

Cognit.AI is at the forefront of utilizing generative AI for gene expression prediction and perturbative oracle techniques, leading to significant advancements in engineering oncolytic viruses. These viruses are intelligently designed to express immune-stimulating molecules like cytokines and bispecific T cell engagers (BiTEs), amplifying their anti-cancer capabilities. By integrating cutting-edge AI technologies into oncolytic virotherapy, Cognit.AI is driving transformative breakthroughs that hold tremendous promise for the future of cancer treatment.

Looking Ahead

While the field of oncolytic virotherapy is still in its relative infancy, the potential of these treatments, especially when combined with advancements in gene expression prediction, is vast.

The path forward will be challenging, but the potential rewards — effective treatments for cancers that currently resist most conventional therapies — are too significant to ignore. The fight against cancer continues, and oncolytic viruses, armed with the power of gene generative AI and expression prediction, are emerging as a powerful weapon in this battle.

Stay tuned.

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