Organoids in Colorectal Cancer: Advances, Uses, and What’s Next

Colorectal cancer (CRC) is a global health crisis: it’s the third most common cancer worldwide and ranks third in mortality in China. For patients, treatment often feels like a roll of the dice—what works for one person may fail for another, and many drugs that succeed in lab models flop in clinical trials. The problem? Traditional cancer models—like flat 2D cell lines or mouse xenografts—don’t capture the genetic diversity and complexity of real human tumors. Enter patient-derived organoids (PDOs): 3D “mini-tumors” grown in the lab that mimic the look, behavior, and genetics of a patient’s cancer. They’re changing how we study CRC—and how we treat it.

This review, written by Deng-Bo Ji and Ai-Wen Wu from the Department of Gastrointestinal Surgery III at Peking University Cancer Hospital & Institute (a leading center for cancer research in China), breaks down the progress, uses, and challenges of CRC organoids.

What Are Organoids, and Why Do They Matter for CRC?

Organoids are tiny, self-organizing clusters of cells grown from a patient’s tumor (or normal tissue) in a nutrient-rich gel. For CRC, scientists start with a small piece of tumor—from a biopsy or surgery—and place it in a 3D matrix with growth factors (like R-spondin, which supports intestinal stem cells). Over weeks, the cells grow into a structure that mirrors the original tumor: it has the same genetic mutations, shape, and even responses to drugs.

Compared to old models, organoids are a game-changer:

They preserve tumor heterogeneity: Real CRC tumors have dozens of genetic variants (called “subclones”)—cell lines often lose these, but organoids keep them.
They’re fast and flexible: Organoids grow in weeks (vs. months for mouse xenografts) and can be frozen, shared, or edited with gene tools like CRISPR-Cas9.
They match patient tumors: Studies show 90% of a tumor’s mutations are present in its organoid—meaning what happens in the dish often happens in the patient.

How Organoids Are Transforming CRC Research

Organoids aren’t just lab curiosities—they’re solving real problems in CRC care. Here are their biggest uses:

1. Unlocking the Genetics of CRC

CRC develops when genes like APC, KRAS, or TP53 mutate and drive uncontrolled growth. Organoids let scientists “build” CRC from scratch to study these mutations. For example:

A 2015 study in Nature by Drost et al. used CRISPR to add mutations in APC, KRAS, TP53, and SMAD4 to normal intestinal organoids. The result? Organoids that grew into invasive tumors when implanted in mice—showing exactly how these mutations turn healthy cells into cancer.
Another 2015 study in Nature Medicine by Matano et al. edited organoids to have five CRC-linked mutations. The organoids grew without the “niche” factors normal cells need—mimicking how cancer cells become independent of their environment.

These experiments help us understand why CRC starts and spreads—and identify new targets for drugs.

2. Predicting Which Chemotherapies Will Work

Chemotherapy is a mainstay for metastatic CRC, but only 30–40% of patients respond. Organoids let doctors test drugs on a patient’s tumor before treatment—avoiding unnecessary side effects.

A 2018 study in Science by Vlachogiannis et al. tested 55 drugs on organoids from metastatic CRC patients. The organoids predicted treatment response with 100% sensitivity (catching all responders) and 93% specificity (ruling out non-responders).
A 2019 study in Science Translational Medicine by Ooft et al. ran a prospective trial (called TUMOROID) on 55 metastatic CRC patients. Organoids correctly predicted response to irinotecan-containing regimens in over 80% of cases—helping doctors skip ineffective treatments.

For patients, this means fewer trips to the hospital, less toxicity, and more hope.

3. Guiding Targeted Therapy for Mutant CRC

Targeted drugs (like EGFR inhibitors) work wonders for some CRC patients—but fail if the tumor has RAS or BRAF mutations. Organoids help test these drugs (and combinations) before they’re given to patients.

A 2016 study in eLife by Verissimo et al. tested RAS-pathway inhibitors on CRC organoids. They found that RAS-mutant organoids were resistant to single drugs—but combining EGFR inhibitors with a BCL-2/BCL-XL inhibitor (navitoclax) killed them. This combo is now being tested in clinical trials.

Organoids also help researchers find “bypasses” for drug resistance—like how cancer cells switch pathways when one is blocked.

4. Predicting Response to Chemoradiotherapy in Rectal Cancer

Locally advanced rectal cancer (LARC) is often treated with neoadjuvant chemoradiation (nCRT)—radiation plus 5-FU or other drugs—before surgery. But response varies: some patients have complete regression (no need for surgery), while others see little benefit. Organoids help predict who will respond.

A 2019 study in Nature Medicine by Ganesh et al. from Memorial Sloan Kettering Cancer Center grew organoids from 20 rectal cancer patients. The organoids’ response to 5-FU and radiation matched the patients’ outcomes—with a strong link between organoid sensitivity and progression-free survival.
A 2020 study in Cell Stem Cell by Yao et al. from Fudan University tested organoids from 80 LARC patients. The organoids predicted nCRT response with 84% accuracy—meaning doctors could soon use organoids to decide who needs surgery and who can try a “watch-and-wait” approach.

Challenges Ahead: What Organoids Can’t Do (Yet)

Organoids are powerful, but they’re not perfect. Here are the biggest hurdles:

No Tumor Microenvironment: Real tumors are surrounded by stromal cells (fibroblasts), blood vessels, and immune cells—these affect how cancer grows and responds to drugs. Organoids lack these, so they can’t mimic interactions like immune cell attack or blood supply. Scientists are adding these cells to organoids (called “co-cultures”), but it’s still early days.
Efficiency and Cost: Growing organoids takes weeks and requires specialized labs. Not all tumor samples work—especially if the biopsy has few live cancer cells. And while success rates are high (~80–90%), they need to be better for routine clinical use.
Standardization: There’s no universal protocol for growing CRC organoids. Different labs use different growth factors or matrices, which can change results. Doctors need standardized methods to trust organoid data.

The Future of CRC Organoids: Toward Precision Medicine

Organoids aren’t a cure for CRC—but they’re a bridge to precision medicine: treating each patient’s cancer based on its unique biology. For example:

A patient with RAS-mutant CRC could have their organoid tested against combo drugs (like EGFR + BCL-2 inhibitors) to find the best treatment.
A rectal cancer patient could use organoids to avoid surgery if nCRT will work.
Researchers could use organoid libraries to test new drugs faster—cutting years off the path to clinical trials.

As Deng-Bo Ji and Ai-Wen Wu write: “CRC organoids conserve the genetic and phenotypic heterogeneities of primary cancers. They could help detect gene-drug associations and perform high-throughput drug screening… The utility of organoids in CRC still warrants further evidence, especially those in clinical trials.”

Conclusion

Organoids are revolutionizing CRC research. They let us study cancer in a way that’s closer to real patients, test drugs faster, and personalize treatment. While there are hurdles to clear—like adding the tumor microenvironment and standardizing protocols—the potential is huge. For CRC patients, this could mean fewer guesses, more effective treatments, and better outcomes. And that’s a win worth waiting for.

doi.org/10.1097/CM9.0000000000000882

Was this helpful?

0 / 0