Concurrence of Emerging Developments in Photobiomodulation and Cancer

Dear Editor,

Photomedicine and Laser Surgery (PMLS) has become a premier forum for cutting-edge ideas on the intercept between photobiomodulation and cancer research. In the last year alone, editorials by Karu ¹ and Lanzafame ² have stressed experimental and clinical evidence supporting the potential anticancer effects of photobiomodulation. New data now also confirm that, under certain parameters, photobiomodulation may be safe for use in cancer patients, despite decades of controversy. ^{3 –8}

In August 2012, “A Preliminary Study of the Safety of Red Light Phototherapy of Tissues Harboring Cancer” reported that daily measurements on 330 tumors for 37 consecutive days demonstrated no measurable effect of low-level laser therapy (LLLT) (670 nm at 5 J/cm² using an LED source) on tumor growth. The authors, therefore, concluded that “LLLT at these parameters may be safe even when malignant lesions are present.” ⁹

This is in accord with clinical results from our group, ^{4,10 –12} where in addition to clinical safety, significant antitumor effects and quality of life improvements were observed with >10 years of follow-up, as well as with experimental and clinical reports from multiple other authors. ^{5 –9} Obviously, determining the optimal treatment parameters and the underlying mechanisms for potential applications in oncology will be an exciting future challenge.

Concurrently, the pillars of our understanding of cancer are being questioned, leading to fundamentally new treatment goals. In a paradigm-changing editorial, Prendergast recently argued that “disorders in microenvironment and peripheral systems that control cancer might increasingly be viewed as primary rather than secondary factors in the root nature of cancer as a clinical disease.” This constitutes “a crucial and radical distinction from prevailing thought, as it implies that cancer may be a symptom of an underlying clinical disorder, rather than the root problem itself that needs to be addressed.” ¹³

Prendergast further suggests that “effective treatment of cancer may not necessarily entail understanding or addressing this complexity, but mastering the use of tissue or systemic systems that have the inherent ability to do so.” Hence, a common thread linking emerging perspectives in oncology and photobiomodulation may well be the restitution of tissue homeostasis-homeokinesis, a microenvironment effect that comprises and extends the Warburg effect previously discussed by our group. ¹⁴

The major conduit for such effects must lie in the activation and modulation by light of central physiological energy pathways. In solid tumors, adenosine triphosphate (ATP) and its P- and A-type receptors jointly with inositol pyrophosphates (which regulate ATP concentration by controlling GCR1 factor) have primordial roles. And photobiomodulation may activate and modulate the production of ATP, adenosine monophosphate-activated protein kinase (AMPK), and inositol pyrophosphates P7-P8, not only through the respiratory chain but also through absorption and transportation of infrared (IR) light by water. ¹⁵ This suggests a pathway back to tissue homeostasis-homeokinesis ^15,16 through the re-establishment by light energy of physiologic rhythms and the enactment of physiologically reparative mechanisms in cancer and other complex diseases.

In another recent PMLS editorial, Arani argued that the field of photobiomodulation appears to be “poised as a fringe science moving toward true legitimacy moving as a photoscience that should eventually, with continued research and validation, progress to be a mainstream science.” ¹⁷ A concurrence of goals between photobiomodulation and cancer research would surely lead the former field to maturity and the latter to new treatment approaches. We look forward to continuing to read and share new findings and ideas on these topics, as we have strived to do in the past. ¹⁸