In vitro study details how the gradual dose escalation of calcitriol, a hormonally active metabolite of vitamin D3, increases prostate cancer cell sensitivity to freezing injury and may provide an alternate combinatorial approach in the treatment of prostate cancer

OWEGO, NY – CPSI Biotech announced today the publication of a peer-reviewed article detailing the potential benefit of the combination of calcitriol pre-treatment and freezing (cryoablation) for targeting prostate cancer. The study, titled Dose Escalation of Vitamin D3 Yields Similar Cryosurgical Outcome to Single Dose Exposure in a Prostate Cancer Model, published in the open access journal Cancer Control January-March 2018 edition ( was a multi-institutional collaboration between researchers from CPSI and Binghamton University.

The article details the impact of exposing prostate cancer cells to a gradually increasing dose of calcitriol over a one month period and then exposing cells to mild sub-freezing temperatures associated with a cryoablative procedure. The study investigated the impact of the application of a gradual calcitriol dose escalation regime in comparison to a single (1 day) high dose exposure regime as well as freezing alone in an in vitro prostate cancer cell model. The data show that exposing cancer cells to calcitriol in combination with mild freezing resulted in increased cell death compared to either treatment alone. Further, the data demonstrated that gradual dose escalation of calcitriol yielded a similar outcome as acute high dose exposure. Commenting on the study, Dr. John M. Baust (President and Lead Scientist, CPSI Biotech) stated “cryoablation is a very effective treatment modality used widely to treat various cancers. One limitation of Cryo is that different cancer cells (stages and types) have been shown to have differing tolerances to mild freezing temperatures associated with the outer edge of the frozen mass. In addition to developing advanced cryoablative devices, one of our foci at CPSI is to identify new combinatorial strategies to increase cancer destruction at these mild sub-freezing temperatures. This study demonstrates that the combination of calcitriol and freezing can yield prostate cancer destruction at temperatures as warm as -15°C, whereas typically temperatures of -40°C or colder are necessary for complete destruction.” Dr. Kimberly Santucci (CPSI Research Scientist and the study’s first author) stated “the anticancer properties of VD3 metabolites, including calcitriol, have been extensively studied and we previously reported on the benefits of the combination of calcitriol and freezing.  While beneficial, previous studies focused on the acute administration and short term exposure of high dose calcitriol.  Clinical translation of that approach would require multiple surgical procedures over several days.  The objective of this study was to model the gradual increase of calcitriol concentration such as might be obtained via a one month oral dosing regimen.  Our findings suggest that the application of gradual dose escalation results in similar sensitization of cancer cells to freezing as an acute high dose regime.”

Ongoing efforts at CPSI continue to build upon this success and are focusing on further development, optimization and testing of new minimally invasive surgical devices designed to treat cancers including prostate, pancreatic, bladder, kidney, esophageal and breast cancer among others. Speaking to the broader device development program at CPSI, Dr Baust noted “an ongoing Phase II SBIR award from NCI has provided CPSI the opportunity to ramp up our R&D studies around our advanced cryoablation device platform in combination with vitamin D3 metabolite pre-treatment for the treatment of liver and pancreatic cancers. This project incorporates several of CPSI’s patented technologies, including our cryoengines, thermal ablation probes and catheters and adjunctive anticancer agents (SensitICERs). With success, these efforts will provide an advanced minimally invasive approach for treating various cancers.” With development underway, CPSI is poised to embark down the commercialization path. To this end, Baust commented “We are actively seeking investors and partners through a variety of mechanisms to join our team to bring this potentially lifesaving technology platform to the market.”

More information on the CPSI’s cryoablation and SensitICER technologies can be found on CPSI’s website at The full press release can be accessed here.