Macrophages are cells of the immune system that protect the host from invading pathogens. But in cancer, macrophages can be “hijacked” by tumors, and made to support their malignant growth and spread. This is a drawback for a major cancer treatment, immunotherapy, which turns the body’s immune system against the tumor. EPFL scientists, working with colleagues at the Roche Innovation Centers in Munich and Basel, have now identified a molecular “switch” that can convert the “hijacked” macrophages into cells that can stimulate the immune system to fight the growth and spread of cancer. The work is published in Nature Cell Biology.
Along with attacking foreign pathogens like bacteria, macrophages also help the body’s organs develop and its wounds heal. Their own behavior is fine-tuned by small molecules that they produce, called microRNAs.
When a tumor begins to develop, macrophages attempt to block its growth. But often tumors hijack them and convert them into what are known as “tumor-associated macrophages”, or TAMs for short.
Now corrupted, TAMs use their microRNAs to shield the tumor from the patient’s immune system, helping it grow and metastasize. This phenomenon is common across many tumor types. It is one of the major obstacles in treating cancer, and often leads to a poor prognosis for the patient.
Michele De Palma’s team at EPFL found how to reclaim TAMs. The researchers genetically modified TAMs to remove their ability to produce microRNAs. As a result, the TAMs were reprogrammed dramatically. Instead of protecting the tumor, the TAMs now signaled the presence of the tumor to the immune system, triggering attacks against it – and did so very efficiently.
Using a bioinformatics approach, the researchers found that the most likely culprit was a small family of microRNAs, called Let-7. This offers a more specific target: blocking Let-7 microRNAs may help instruct the TAMs to stimulate anti-tumor immunity.
Interestingly, the researchers observed that reprogramming TAMs also stops cancer cells from leaving the primary tumor. This could mean that the approach can also prevent tumor metastasis, the most threatening aspect of cancer. Moreover, the researchers found that the re-educated TAMs could enhance the anti-tumoral efficacy of certain cancer immunotherapies, some of which are already approved for patients.
However, more work is needed to translate all these findings to actual therapies, especially since there is currently no way to block the Let-7 microRNAs selectively in TAMs. But De Palma’s lab is now working with bioengineers at EPFL to design drugs that can target the Let-7 microRNAs specifically in the TAMs.
Some of the most promising cancer treatments are immunotherapies, which are based on provoking or enhancing the patient’s immune response against their tumor. “The most exciting finding was that TAM reprogramming greatly improved the efficacy of immunotherapy,” says Michele De Palma. “Our results in experimental models of cancer suggest a new therapeutic strategy based on inhibiting the microRNA machinery – or the Let-7 microRNAs – specifically in the TAMs, which may unleash the power of mainstream immunotherapies, such as immune checkpoint inhibitors”.
Learn more: Reclaiming the immune system’s assault on tumors
The Latest on: Immunotherapy
via Google News
The Latest on: Immunotherapy
- Cancer Immunotherapy Market 2020 Clinical Survey Report – Roche, Bayer, Eli Lilly, Merck, Novartison February 1, 2020 at 12:39 am
The Cancer Immunotherapy Market report is a compilation of first-hand information, qualitative and quantitative assessment by industry analysts, inputs from industry experts and industry participants ...
- Enhancing cancer immunotherapy with nanomedicineon January 31, 2020 at 5:49 am
However, efforts to develop new immunotherapy agents or combination treatments to increase the proportion of patients who benefit have met with challenges of limited efficacy and/or significant ...
- Neoadjuvant checkpoint blockade for cancer immunotherapyon January 30, 2020 at 10:57 am
1 Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. 2 Bloomberg-Kimmel Institute for Cancer Immunotherapy, Sidney Kimmel Comprehensive Cancer Center, ...
- Immunotherapy called ‘the future of cancer care,’ but not without risks, costs: Health Matterson January 30, 2020 at 8:27 am
Q: What is immunotherapy, and what kinds of cancer can it treat? A: Immunotherapy is a cancer treatment that activates a patient’s immune system to identify and destroy diseases such as cancer.
- Cancer Immunotherapy Market Size to Hit US$ 115.4 Bn by 2026on January 30, 2020 at 7:38 am
The global cancer immunotherapy market is expected to grow at a noteworthy CAGR of around 10.6% during the forecast period 2019 to 2026 LOS ANGELES, Jan. 30, 2020 /PRNewswire/ -- The Cancer ...
- Dual-mechanism based CTLs infiltration enhancement initiated by Nano-sapper potentiates immunotherapy against immune-excluded tumorson January 30, 2020 at 2:40 am
Here we report a dual-mechanism based CTLs infiltration enhancer, Nano-sapper, which can simultaneously reduce the physical obstacles in tumor microenvironment and recruiting CTLs to potentiate ...
- Immunotherapy Drugs Market :Find Out How Market Is Developing Globally In The Forseen Years 2020-2029?on January 28, 2020 at 11:45 pm
A recent market research analysis titled, Immunotherapy Drugs Market offers insightful information to the clients escalating their basic leadership size explores distinct significant facets associated ...
- Global cancer immunotherapy market is expected to grow with a CAGR of 15.12% over the forecast period from 2019-2025on January 28, 2020 at 9:20 am
The report on the global cancer immunotherapy market provides qualitative and quantitative analysis for the period from 2017 to 2025. The report predicts the global cancer immunotherapy market to grow ...
- HPV-Cancer Targeting Immunotherapy Enters Phase 1 Clinical Trial After Showing Success In Animalson January 24, 2020 at 6:40 am
The paper highlights the candidate’s ability to target and shrink HPV motivated tumors in both animal studies and human blood samples.
- OncoCyte Enters Into The Cancer Immunotherapy Field With The Acquisition Of Insight Geneticson January 23, 2020 at 1:46 am
OncoCyte surprises us again with an acquisition, this time it has been Insight Genetics (IG). This acquisition enables OCX to enter into the oncological immunotherapy field. A potential market of ...
via Bing News