Making The Microbiome More Receptive To Immunotherapy For Cancers

A New Study Examines The Gut-Cancer Treatment Impact Of A Fiber-Based Gel.
Having A Healthy Gut Microbiome—The Collection Of Microorganisms That Reside In Our Gastrointestinal Tracts—Can Affect Us In A Variety Of Ways, Including Our Metabolism And Our Mood. Additionally, Studies Show That The Gut Microbiome May Influence How The Immune System Responds To Pathogens. Unbalances In The Gut Microbiome May Also Affect The Way Certain Cancer Treatments Work, According To New Research.

Now, Researchers Funded By The Nibib Are Looking Into Whether A Fiber-Based Gel Can Help Restore Beneficial Gut Microbes So That Immune Checkpoint Inhibitors, A Type Of Cancer Immunotherapy Treatment, Have A Greater Impact On Their Effectiveness.

It Is An Artistic Depiction Of The Digestive System’s Microbiome.

The Gut Microbiome As Seen Through The Eyes Of An Artist. Image By Istock
Human Health And Disease Can Be Affected By Changes In The Gut Microbiome, Which Is Still A Developing Field Of Study In Science. These Results Show That Biomaterials Can Be Used To Alter The Gut Microbiome And Thus Regulate Immune Responses And Potentially Enhance Current Cancer Treatments.

Our Own Immune System Is Enlisted In Cancer Immunotherapy To Identify And Destroy Cancer Cells. Immune Checkpoint Inhibitors Are The Most Common Form Of Cancer Immunotherapy, And They Block Interactions Between Immune Cells And Cancer Cells That Would Otherwise Impede Their Ability To Kill Cancer Cells. Only A Small Percentage Of Cancer Patients Benefit From This Approach, Despite The Fact That It Has Revolutionised Cancer Treatment. This Treatment May Not Work As Well For Patients With Imbalances In Their Gut Microbiome, Research Suggests.

To Improve Cancer Immunotherapy, Many Labs Are Investigating Ways To Manipulate The Gut Microbiome, Including Through Oral Probiotics Or Faecal Microbiota Transplantation. Another Approach Is To Develop A Colon-Retentive Gel Made Of Inulin, A Widely Consumed Food Fibre That Can Modulate The Gut Microbiome To Improve Cancer Immunotherapy Responses.

Prebiotics, Such As Inulin, Are Nondigestible Substances That “Feed” Healthy Gut Bacteria, Thereby Stimulating The Growth Of Only Beneficial Microbes. There Is A Wide Variety Of Foods And Herbs That Contain Inulin, Which Has Been Shown To Increase The Growth Of Beneficial Bacteria In The Human Gut. Using These Findings As A Foundation, The Researchers Tested Whether Inulin Could Boost Responses To An Immune Checkpoint Inhibitor In A Variety Of Cancer-Bearing Mice.

Tumor-Bearing Mice Given Inulin And An Immune Checkpoint Inhibitor Had Less Cancer Growth And A Higher Survival Rate Than Mice Given Only The Immune Checkpoint Inhibitor, According To A Study Published In Nature Biomedical Engineering. These Treatments Were Also Tested To See How They Affected The Mice’s Gut Microbiome. Combining Immunotherapy With A Checkpoint Inhibitor Significantly Increased The Levels Of Several Beneficial Bacteria—Some By More Than 15-Fold—That Have Been Linked To A Positive Response In Cancer Patients. One Type Of Beneficial Bacteria Was Nearly Eradicated By The Immune Checkpoint Inhibitor Treatment On Its Own, But The Inulin Treatment Was Able To Restore Some Of The Bacteria.

If Prolonged Exposure To Inulin In The Gut Could Further Amplify Its Effect, The Researchers Wanted To Investigate. They Created A Viscous Inulin Gel For Oral Administration That Likely Coats The Lining Of The Mice’s Colons. Treatment With An Immune Checkpoint Inhibitor And The Inulin Gel Delayed Tumour Growth In The Mice Significantly More Than Treatment With An Immune Checkpoint Inhibitor And Unmodified Inulin.

Additionally, The Scientists Examined How Inulin Gel And An Immune Checkpoint Inhibitor Impacted The Immune System Of The Mice When Used In Combination. According To Their Findings, This Treatment Improved Antitumor T Cell Responses (White Blood Cells That Can Attack Cancer Cells).

To Improve Cancer Immunotherapy Treatment In Mice, We Developed A Biomaterial That Specifically Targets And Manipulates Beneficial Bacteria In The Intestines.” Cancer Patients May Be Able To Restore A Healthy Gut Microbiome Using Our Colon-Retentive Inulin Gel In The Future.”

A Clinical Trial In Cancer Patients Could Come After A Preclinical Study In Healthy Volunteers, According To Moon, Who Stressed The Importance Of His Research’s Preclinical Nature.