A sig­nif­i­cant number of prostate cancer patients are treated with a com­bi­na­tion of radi­a­tion and chemotherapy, according to Sri Sridhar, Dis­tin­guished Pro­fessor of Physics in the Col­lege of Sci­ence.

While com­bi­na­tion therapy can have a syn­er­gistic effect, the approach has draw­backs, said Sridhar’s col­league, Paul Nguyen, an assis­tant pro­fessor of radi­a­tion oncology at Har­vard Med­ical School. “Both of these are lim­ited by the col­lat­eral damage they cause to the rest of the body,” he explained.

For the last two years, Sridhar has worked with Nguyen and med­ical physi­cists Mike Mak­ri­giorgos, Robert Cor­mack and Anthony D’Amico of the Dana-​​Farber Cancer Insti­tute to develop a method that could make the com­bi­na­tion therapy less toxic and pos­sibly more effec­tive at curing prostate cancer.

The clin­i­cians at Dana-​​Farber iden­ti­fied the chal­lenges and the prob­lems and we find the nan­otech­nology solu­tions to them,” Sridhar said. “We’re really bringing together the nanomed­i­cines we’re devel­oping here at North­eastern to address their key clin­ical challenges.”

Last month, the United States Depart­ment of Defense Prostate Cancer Research Pro­gram awarded Sridhar’s inter­dis­ci­pli­nary group a three-​​year $560,000 grant to pursue this work in pre­clin­ical trials. Their pro­posal beat out more than 900 others for one of 60 grants focusing on prostate cancer research.

The toxic effects of tra­di­tional chemotherapy tech­niques force patients to wait for two to three weeks between injec­tions, Sridhar explained. “And then the drug is only in the prostate for a short period of time.”

Radi­a­tion therapy, on the other hand, is sus­tained over sev­eral weeks. A com­monly used radi­a­tion tech­nique, called brachytherapy, allows doc­tors to implant radioac­tive seeds directly into the prostate, ensuring a local­ized deploy­ment of the treat­ment. Cur­rently, no sim­ilar tech­nique exists for chemotherapy.

Inert plastic spacers are cur­rently used to locate the radioac­tive seeds within a tumor. Sridhar’s team is designing “smart” spacers by adding nanopar­ticle coat­ings that release chemotherapy drugs directly into the tumor without infil­trating the rest of the body.

The advan­tage of releasing it in the prostate,” Sridhar said, “is we can do it con­tin­u­ously and sys­tem­at­i­cally in a sus­tained manner over the course of the radi­a­tion treatment.”

The new tech­nique, called Bio­log­ical In Situ Image Guided Radi­a­tion Therapy, or BIS-​​IGRT, devel­oped by the Northeastern-​​Dana Farber team, has the poten­tial to cause a par­a­digm shift in the clin­ical prac­tice of chemo and radi­a­tion therapy, Sridhar said. The tech­nique, he noted, car­ries no addi­tional burden for the patient.

Nguyen has already iden­ti­fied a sub­group of patients that could ini­tially ben­efit from the therapy.

We have the patients in need and can gen­erate a wish-​​list of what kinds of tech­nolo­gies we would like to have to treat our patients with,” Nguyen said. “But it takes nan­otech­nology dream-​​makers like pro­fessor Sridhar and his team to turn some of these dreams into real­i­ties that can have an imme­diate and real impact on patients facing aggres­sive cancers.”

View selected pub­li­ca­tions of Sri Sridhar in IRis, Northeastern’s digital archive.