Stephen Hatfield<\/a>, a professor at Bouv\u00e9 College of Health Sciences and director of the pharmaceutical and biomedical sciences graduate program share their thoughts with Northeastern Global News.<\/p>\nHow does a cancer vaccine work?<\/p>\n
\u201cWe always think about administering vaccines in healthy individuals with the hope that it will prevent disease from those. But when it comes to cancer, it\u2019s more of a therapeutic strategy,\u201d Amiji said.<\/p>\n
Vaccines give the immune system a preview of a threat, teaching it to recognize proteins called antigens found on the surface of foreign cells. A type of immune cell known as B-cells respond by producing antibodies. If antigens are the locks that need to be targeted, antibodies function as keys that bind to them, disabling the invading cell or flagging it for destruction by other immune cells. The immune system remembers the target and responds quickly the next time.\u00a0<\/p>\n
Some vaccines rely on messenger RNA, or mRNA, which is an abridged version of DNA instructions for building proteins. Instead of teaching the body to recognize pathogens, the way regular vaccines do, mRNA vaccines teach the body to make antigens from scratch.\u00a0<\/p>\n
Cancer vaccines use this strategy against tumors, Hatfield explained.\u00a0<\/p>\n
These vaccines contain mRNA carrying instructions for making specialized abnormal proteins that are a result of mutations in cancer cells. The cells make copies of these proteins, known as neoantigens, thereby providing the immune system with a molecular mugshot of what to hunt down.<\/p>\n
\u201cIt trains our immune system to recognize the tumor as being different from healthy tissue,\u201d Amiji said.<\/p>\n
![\"Stephen](\"https:\/\/www.newsbeep.com\/il\/wp-content\/uploads\/2026\/08\/120823_AS_Stephen_Hatfield_044.jpg\")
Northeastern professor Stephen Hatfield says personalized cancer vaccines show promise by activating T-cells against multiple targets. Unique to a patient\u2019s tumor, those targets are different abnormal proteins that distinguish cancer cells from healthy ones. Photo by Alyssa Stone\/Northeastern University<\/p>\n
What makes the vaccine personalized?<\/p>\n
Scientists start with a biopsy, Hatfield said, removing a bit of cancerous tissue from a patient. They then compare the genetic material of tumor cells with healthy tissue, flagging mutations in the cancerous tissue that produce neoantigens.<\/p>\n
Every tumor has a unique mix, Amiji explained. \u201cSo if I was a patient, my signature may be slightly different from someone else\u2019s,\u201d he added.<\/p>\n
The Moderna-Merck vaccine includes mRNA for up to 34 possible neoantigens unique to the patient\u2019s tumor, according to the companies.<\/p>\n
Once injected, the mRNA prompts cells to produce copies of those targets, Hatfield explained. That activates immune system ground fighters known as T-cells. They multiply and fan out, looking to directly attack cells displaying the same neoantigens.<\/p>\n
\u201cNow you have an army of T-cells that circulate and try to find that particular antigen,\u201d Hatfield explained. \u201cThe only place, hopefully, that they find that is in the tumor,\u201d he added.<\/p>\n
Why is the second drug, Keytruda, an important component?<\/p>\n
To kill a cancer cell, T cells have to make direct physical contact with it, Hatfield explained.<\/p>\n
The problem is, tumors can hide from the attack by exploiting the system of cellular \u201coff switches\u201d the body uses to keep the immune system in check, a mechanism known as immune checkpoints.<\/p>\n
Borrowing from \u201cStar Trek,\u201d Amiji said the tumor puts up a StarFleet-style shield that makes direct access difficult.\u00a0<\/p>\n
Keytruda, helps by blocking one of the off switches and allowing the T-cells to keep working, he explained.\u00a0<\/p>\n
Together the two treatments are \u201cpoking two different pathways,\u201d Hatfield said. The vaccine trains T-cells to find their target, while Keytruda clears the way for the attack.\u00a0<\/p>\n
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<\/p>\n
Does it matter that the vaccine showed success in a phase 3 trial?\u00a0<\/p>\n
Before new treatments can become widely available, they have to clear several rounds.<\/p>\n
\u201cPhase one is safety,\u201d Hatfield said. \u201cThey want to make sure this is going to be safe for larger trials.\u201d<\/p>\n
Phase two involves a small cohort and tests whether the treatment appears to work as intended and improve outcomes.<\/p>\n
Finally comes the big test. \u201cIn phase three, they increase the number of patients,\u201d Hatfield said.<\/p>\n
Increasing the number of patients helps make the experiment more robust, since the more patients the vaccine has been tested on, the more confident the scientists can feel in their findings.<\/p>\n
What else should we note about the vaccine?<\/p>\n
The fact that the scientists couldn\u2019t detect new tumors suggests the primed T cells may have successfully hunted down cancer cells too small to show up in the imaging that researchers use to look for tumors, Hatfield said.<\/p>\n
Amiji is also excited about the ability to identify each patient\u2019s unique neoantigens and rapidly build an mRNA vaccine around them.\u00a0<\/p>\n
However, this personalization comes with a practical challenge. \u201cHow can this be developed for thousands of patients in a finite amount of time?\u201d he asked.<\/p>\n
Moreover, the companies have yet to release detailed efficacy data from the Phase 3 trial, leaving experts uncertain just how big the benefit was.<\/p>\n
\u201cAs scientists, we always want to look at data and make objective assessments,\u201d Amiji explained.\u00a0<\/p>\n
He said he remains \u201ccautiously optimistic,\u201d noting that the key question is how much better the combination performed than Keytruda alone.<\/p>\n
Hatfield added that the reported safety results are encouraging. While Keytruda comes with side effects such as inflammation, the vaccine didn\u2019t cause a significant increase.<\/p>\n
![\"Mansoor](\"https:\/\/www.newsbeep.com\/il\/wp-content\/uploads\/2026\/08\/neu_m046tn52p.jpg\")
Northeastern professor Mansoor Amiji says personalized cancer vaccines could open the door to treating other cancers, but scientists will need to overcome barriers that make some tumors harder for the immune system to reach. Photo by Matthew Modoono\/Northeastern University<\/p>\n
Can other cancers be targeted this way?<\/p>\n
\u201cI think this is a first step,\u201d Amiji said, adding that \u201cthere\u2019s a huge number of opportunities here.\u201d\u00a0<\/p>\n
Melanoma has been a go-to candidate because, as a skin cancer, it\u2019s easy to access. However, immunotherapy could also target breast, ovarian, lung, pancreatic and brain tumors, he said.<\/p>\n
However, there are some formidable obstacles.<\/p>\n
Brain tumors are particularly difficult to access with immunotherapy given the barriers to delivering drugs to the brain, Amiji said. Likewise, pancreatic cancer, ovarian cancer \u201ckeep the T-cells at bay,\u201d he added.\u00a0<\/p>\n
Making immunotherapy work against such cancers may require finding ways to help T-cells penetrate tumors, he explained.<\/p>\n
Timing matters, too. These therapies work best if you diagnose patients early, before the disease and other treatments have taken a greater toll on the patient, Amiji said.\u00a0<\/p>\n
\u201cOne of the biggest calls to action\u201d is to \u201ccome up with better screening tools\u201d and other ways to identify cancers early and improve outcomes, Amiji said.<\/p>\n
Hatfield said that Northeastern University\u2019s department of pharmaceutical sciences is launching a new master\u2019s degree in immunotherapy and precision medicine focused on using the immune system to develop targeted treatments.<\/p>\n
Katya Poltorak is a science reporter at Northeastern Global News. Email her at e.poltorak@northeastern.edu.<\/p>\n","protected":false},"excerpt":{"rendered":"There\u2019s a new weapon in the cancer fighting arsenal.\u00a0 In a joint statement, biotech companies Moderna and Merck…\n","protected":false},"author":2,"featured_media":591070,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[114,267362,85,4143,46,69431,22373],"class_list":["post-591069","post","type-post","status-publish","format-standard","has-post-thumbnail","category-business","tag-business","tag-cancer-therapeutics","tag-il","tag-immunotherapy","tag-israel","tag-mrna","tag-vaccine-research"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/591069","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/comments?post=591069"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/591069\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media\/591070"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media?parent=591069"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/categories?post=591069"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/tags?post=591069"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}