By Animesh Samanta
In 2022, nearly 9.7 million people worldwide lost their lives to cancer, with 20 million new cases reported globally. These stark numbers reflect a sobering reality: despite decades of research and advances in treatment, cancer remains one of humanity’s most stubborn adversaries. But a growing field—nanomedicine—is offering a new way forward, and it might just redefine how we treat the disease.
At the heart of nanomedicine are nanoparticles, minuscule structures often smaller than a virus, capable of navigating the body’s labyrinthine systems to deliver drugs with more than surgical precision. These microscopic tools are now being engineered to build “smart” platforms that target tumours directly, carry cancer-killing agents, and even sense what’s happening inside the body in real time.
At least 15 nanomedicines have already received regulatory approval for cancer treatment, and over 80 more are currently being investigated in more than 200 clinical trials worldwide. As this technology matures, it is poised to change not just how we treat cancer—but how we understand and interact with our own biology.
Turning light into heat
One of the most exciting developments in this area is photothermal therapy. This technique involves shining light, typically from a laser, onto tumours where specially designed particles absorb the energy and convert it into heat. That heat, in turn, can destroy cancer cells while sparing nearby healthy tissue.
While the use of light in medicine dates back to ancient civilisations—sunlight was once used to treat conditions like psoriasis and vitiligo—modern photothermal therapy is far more targeted and sophisticated. Instead of relying on the sun, researchers use laser light tuned to specific wavelengths, and instead of crude topical applications, they employ nanoparticles engineered to travel through the bloodstream and accumulate in tumours.
But there’s a catch: our bodies are full of light-absorbing molecules, called chromophores. These are natural pigments like hemoglobin in blood or melanin in skin that can inadvertently absorb the laser light, causing unwanted damage to healthy tissue.
To address this, researchers have turned to exogenous photothermal agents—materials introduced from outside the body. One class of these agents, organic dyes, can be engineered to absorb specific wavelengths of light. Nanoparticles as thermal agents or organic dyes attached with nanoparticles, can be delivered straight to tumours, where they perform their light-to-heat transformation with minimal collateral damage.
Heat with precision
Still, heat is a blunt tool. Laser treatment using photothermal agents typically treats cancer by raising temperatures in the tumour cells by 4-6 degrees Celsius. The catch is that raising temperatures by more than 6 degrees Celsius can damage surrounding healthy tissues as well. Monitoring temperature during treatment is vital, but technically challenging.
Now, researchers are developing “smart” nanomedicine platforms that can not only deliver heat for the treatment but also monitor the body’s response in real time.
An international team including this author previously demonstrated nanoparticles based thermal agents that can generate heat and cure cervical tumours in mice models. An interdisciplinary team at Shiv Nadar University in India which spans chemistry, physics and life sciences is now working on integrating nanocarriers, photothermal agents and temperature sensors in a single package.
This three-in-one system could allow clinicians to deliver heat with precision, minimising damage to healthy cells and improving treatment outcomes.
A growing crisis
This innovation comes at a crucial time. Breast cancer is now the most commonly diagnosed cancer worldwide and the leading cause of cancer-related death among women. Since 2008, global incidence has risen by more than 20 percent. Each year, about 1.5 million women are diagnosed, and the disease accounts for a quarter of all female cancer cases.
In India, the shift has been particularly striking. Just a few decades ago, cervical cancer was the most prevalent cancer among Indian women. But by the early 2000s, breast cancer had overtaken it, with incidence climbing sharply across the country.
According to data from the National Cancer Registry Programme, breast cancer rates in India have continued to rise, especially in urban areas. Alarmingly, Indian women are being diagnosed at younger ages compared to their Western counterparts, sometimes in their 30s or early 40s.
In 2018 alone, India reported approximately 1.16 million new cancer cases. Of those, 162,000 were breast cancer, and nearly half of the women diagnosed did not survive. These figures underscore the urgent need for more targeted, less toxic treatment options.
Rethinking chemotherapy
Traditional cancer treatments such as chemotherapy and immunotherapy have saved countless lives—but they come at a cost. These treatments are often non-specific, attacking both cancerous and healthy cells. The resulting side effects, from fatigue and hair loss to immune suppression and organ damage, can be debilitating.
Nanomedicines promise a gentler alternative. By delivering drugs directly to tumour sites, they can reduce off-target effects while maintaining or even enhancing effectiveness.
There are several kinds of nanoparticles. Lipid-based nanoparticles mimic the body’s own fat molecules and can carry water-soluble drugs. Polymeric nanoparticles are made from biodegradable plastics and allow for slow, controlled release. Inorganic nanoparticles, such as gold or iron oxide particles, are often used for both imaging and treatment.
What they all have in common is their ability to exploit a phenomenon known as the enhanced permeability and retention (EPR) effect. Tumours tend to have leaky blood vessels and poor drainage, which allows nanoparticles to slip in and stay put. This passive targeting mechanism has become a cornerstone of modern nanomedicine.
The first nanomedicine approved by the US Food and Drug Administration was Doxil, a PEGylated liposomal formulation of the chemotherapy drug doxorubicin. “PEGylation” involves coating particles in polyethylene glycol to extend their circulation time, while “liposomes” are tiny fat bubbles that protect the drug until it reaches its target.
Since then, others such as Abraxane and Apealea have followed and are now routinely used in breast cancer treatment. These nanomedicines have proven effective in shrinking tumours while causing fewer side effects than their traditional counterparts.
What comes next?
Nanomedicine is not a silver bullet. Challenges remain—manufacturing consistency, cost, regulatory hurdles, and questions about long-term safety, all need to be addressed. But the field is maturing rapidly, and its potential is vast.
As researchers refine multifunctional platforms that combine diagnosis, monitoring and treatment in a single nanoparticle, a new era of cancer care is emerging. In the coming years, as these therapies progress from lab benches to hospitals, they may transform breast cancer from a life-threatening diagnosis into a condition that can be managed with precision and dignity.
Dr. Animesh Samanta is an Associate Professor at Shiv Nadar University, with prior research experience as a Postdoctoral Fellow at A*STAR-SBIC, Singapore, and a PhD from the National University of Singapore. His research focuses on the development of fluorescent probes for tracking reactive biomolecules and microenvironments, alongside nanoparticle-based multimodal imaging approaches for cancer diagnostics and therapy, including photothermal therapy (PTT), PDTand chemotherapy.
Originally published under Creative Commons by 360info™.
