A recent article published in the journal ACS Nano discusses the application of Escherichia coli (E. coli)-mimetic nanomaterials for photolytic treatment of CT-26 or 4T1 tumors.
The authors synthesized the target nanomaterials using E. coli membrane proteins, gold nanorods (AuNRs), and adhesion proteins and named them E. coli-mimetic AuNRs (ECA). Further, the synthesized ECA showed a preventive effect in mice with CT-26 or 4T1 tumors under 808-nanometer laser irradiations.
Metastasis or reoccurrence are the key reasons behind the increase in cancer mortality, and treating recurrent or metastatic cancers is the end goal of cancer therapy. Combination therapy is an effective treatment for metastasis and reoccurrence. Further, combining nanomaterial-based phototherapy with chemotherapy has a scope in cancer treatment.
Nanomaterials in Cancer Therapy
Selective treatment of cancer cells through immunotherapy involves activation of immune cells, especially T lymphocytes aiding in eliminating cancer by inducing antigen-specific cytotoxicity. In this context, the dendritic cells (DCs) activated T cells selectively destroy antigen-expressing cells in cancer treatment.
Photothermal therapy (PTT) used for localized cancer treatment involves light energy conversion into thermal energy upon irradiation with a near-infrared (NIR) laser.
Nanomaterials can carry drugs to specific targets and aid in effective disease treatment. Further, they are used in combinational therapy to deliver more than one drug. Moreover, nanoparticles based on inorganic materials such as iron oxide nanoparticles, mesoporous silica nanoparticles, AuNRs, and quantum dots are effective PTT agents. AuNRs are efficient for photothermal conversion and surface functionalization and have good biocompatibility. However, cetyltrimethylammonium bromide (CTAB) on their surface makes them highly toxic, and surface modification of AuNRs helps reduce their toxicity.
ECA in Cancer Treatment
In the present study, the authors optimized the sonication and temperature conditions to synthesize ECA. Under NIR irradiation, while the AuNR in ECA had a phototherapeutic effect, the anticancer immunity was induced by the adhesion and surface proteins of ECA. Further, the authors used the synthesized ECA to treat primary tumors and secondary metastatic cancer in mice. The results revealed that the NIR laser light at 808 nanometers raised the temperature in ECA-treated tumor cells and induced apoptotic or necrotic cell death, exhibiting a therapeutic effect on CT-26 and 4T1 tumors in mice.
ClearColi lysate, fimbrin D-mannose-specific adhesin (FimH), and NIR laser irradiation activated immune cells, including T cells and DCs in tumor-draining lymph nodes (tdLNs). Finally, the mice transplanted with CT-26 or 4T1 tumors were cured of the primary tumor and blocked secondary lung metastasis on treatment with ECA.
ECA Characterization and Evaluation of its Therapeutic Potential
The morphology of ECA was analyzed by employing transmission electron microscopy (TEM). The resulting images showed a liposomal corona on the surface of AuNR on the peripheral side of liposome-coated AuNR (LCA) and ECA. The dynamic light scattering (DLS) studies revealed that the hydrodynamic sizes of LCA and ECA were 93.72 ± 2.7 and 116.8 ± 6.5 nanometers, respectively. Further, LCA and ECA showed a negative zeta potential of −4.6 and −12.7 millivolts.
The analysis of ECA using Fourier-transform infrared (FT-IR) spectra revealed characteristic peaks of phospholipids at 1735-centimeter inverse that corresponds to the carbonyl group, 1230-centimeter inverse to metaphosphate ion (PO2−), 1075-centimeter inverse to ether linkage (C-O-O) and peaks at 1646, and 1394-centimeter inverse that corresponds to amide bond. This data confirmed ECA modification with phospholipids, ClearColi lysate, and FimH on the surface of AuNR.
The studies of the photothermal effect of AuNR, LCA, and ECA revealed that the NIR irradiation on these nanomaterials induced a temperature rise and stimulated apoptotic/necrotic cell death. However, there was no temperature rise or apoptotic/necrotic cell death without laser irradiation, thus confirming the application of AuNR, LCA, and ECA as photothermal materials for tumor treatment.
Further, injecting Bagg Albino (BALB/c) mouse with PBS, liposome, FimH, liposome + FimH, AuNR, LCA, and ECA and irradiating with NIR laser of 808 nanometers showed a temperature rise at the tumor sites of AuNR, LCA, and ECA. However, the tumors treated with PBS, liposome, FimH, liposome + FimH had no response. Twenty days after treatment, the mice did not show tumor growth, reoccurrence, liver toxicity, or alanine aminotransferase (ALT) levels elevation in serum. This confirms the potential of AuNR, LCA, and ECA as PTT agents against tumors.
Later, the authors observed that the mice treated with AuNR and LCA PTT agents as the first tumor treatment showed partial resistance to the second cancer challenge without antigen-specific T-cell activities. However, the ECA PTT treatment stimulated antigen production and immune activation to promote antigen-specific immune activity, thus protecting against lung metastatic cancer (second challenge) in mice.
Conclusion
The authors of this study realized the goal of treating cancer metastasis or recurrence with a novel ECA nanomaterial. The synthesized ECA upon NIR laser irradiation-induced immune cell activation in the tumor-draining lymph nodes. Further ECA showed a therapeutic effect against CT-26 colonic epithelial cell carcinoma and 4T1 orthotopic breast cancer.
Thus, the results show the dual functionality of ECA nanomaterials as PTT for primary cancer treatment and immunotherapy against recurrence and metastasis. The authors believe that ECA will be used to block metastasis and treat primary cancers in humans in the future.
News
X Marks the Spot: AI’s Treasure Maps Lead to Early Disease Detection
Medical diagnostics expert, doctor’s assistant, and cartographer are all fair titles for an artificial intelligence model developed by researchers at the Beckman Institute for Advanced Science and Technology. Their new model accurately identifies tumors [...]
Scientists Discover Method To Identify Alzheimer’s Disease Before It Progresses to Dementia
Researchers at Aarhus University have discovered a method to identify Alzheimer’s disease before it progresses to dementia, potentially opening up new avenues for treatment. A groundbreaking study could pave the way for early detection [...]
Startling Discovery: COVID-19 Virus Can Stay in the Body More Than a Year After Infection
The COVID-19 virus can persist in the blood and tissue of patients for more than a year after the acute phase of the illness has ended, according to new research from UC San Francisco that offers potential [...]
New bioengineered protein design shows promise in fighting COVID-19
In the wake of the COVID-19 pandemic, scientists have been racing to develop effective treatments and preventatives against the virus. A recent scientific breakthrough has emerged from the work of researchers aiming to combat [...]
Sugar-coated gold nanoparticles can quickly eliminate bacterial infections, no antibiotics required
If left to their own devices, bacteria on our teeth or wounded skin can encase themselves in a slimy scaffolding, turning into what is called biofilm. These bacteria wreak havoc on our tissue and, [...]
Liquid Lightning: Nanotechnology Unlocks New Energy
EPFL researchers have discovered that nanoscale devices harnessing the hydroelectric effect can harvest electricity from the evaporation of fluids with higher ion concentrations than purified water, revealing a vast untapped energy potential. Evaporation is a natural [...]
Unmasking the Illusion: AI-Generated Faces Challenge Perceptions
Research shows survey participants duped by AI-generated images nearly 40 percent of the time. If you recently had trouble figuring out if an image of a person is real or generated through artificial intelligence [...]
New Discovery Reveals How Cells Defend Themselves During Stressful Situations
Stress granules play a crucial role in the stress response, arising from the aggregation of non-translating mRNAs and proteins. Although significant knowledge exists about stress granules, the mechanisms behind their mRNA localization remain partially [...]
Scientists use a new type of nanoparticle that can both deliver vaccines and act as an adjuvant
Many vaccines, including vaccines for hepatitis B and whooping cough, consist of fragments of viral or bacterial proteins. These vaccines often include other molecules called adjuvants, which help to boost the immune system's response [...]
Not Science Fiction: How Optical Neural Networks Are Revolutionizing AI
A novel architecture for optical neural networks utilizes wavefront shaping to precisely manipulate the travel of ultrashort pulses through multimode fibers, enabling nonlinear optical computation. Present-day artificial intelligence systems rely on billions of adjustable [...]
Turning skin cells into limb cells sets the stage for regenerative therapy
In a collaborative study, researchers from Kyushu University and Harvard Medical School have identified proteins that can turn or “reprogram” fibroblasts — the most commonly found cells in skin and connective tissue — into [...]
AI reveals prostate cancer is not just one disease
Artificial Intelligence has helped scientists reveal a new form of aggressive prostate cancer, which could revolutionise how the disease is diagnosed and treated in the future. A Cancer Research UK-funded study, published in Cell Genomics, has revealed [...]
New Study Finds That Persistent COVID-19 Infections Are Surprisingly Common
Recent research conducted by the University of Oxford has found that a high proportion of SARS-CoV-2 infections in the general population lead to persistent infections lasting a month or more. The findings have been published in the journal Nature. [...]
Innovative nanosheet method revolutionizes brain imaging for multi-scale and long-term studies
The human brain has billions of neurons. Working together, they enable higher-order brain functions such as cognition and complex behaviors. To study these higher-order brain functions, it is important to understand how neural activity [...]
Scientists Have Discovered a Potential Universal Antivenom
Scientists at Scripps Research identified antibodies that protect against a host of lethal snake venoms. Scripps Research scientists have developed an antibody that can block the effects of lethal toxins in the venoms of [...]
Scientists discover the human brain is even more powerful than we thought
The human brain could be far more powerful than we ever imagined, scientists have discovered. Researchers have identified cell messaging which have never been uncovered before, which suggests our brains are capable of more than previously realised. It’s [...]