Abstract 3213
Background
Photodynamic therapy (PDT) is one of actively developing modalities of cancer treatment. During PDT procedure systemically injected photosensitizer molecules are activated by laser irradiation in tumor location leading to generation of singlet oxygen which induces cytotoxic effect. In modern clinical practice PDT uses continuous wave irradiation. In such mode fast depletion of molecular (triplet) oxygen in tissue occurs leading to reduction of PDT efficiency. Previously we have shown that photodynamic treatment using pulse mode irradiation regimens could be more efficient in damaging tumor cells than standard PDT due to reoxygenation (Klimenko et. al., Photodiagnosis Photodyn Ther., 2016). In present study we have evaluated specially designed pulse mode PDT regimes on tumor model in vivo.
Methods
PDT pulse mode irradiation regimens were designed using physics and mathematical modelling. BALB/c male mice were subcutaneous injected into right flanks with CT26 murine colon carcinoma cells. At day ten after inoculation mice were randomized into 3 groups with 10 animals in each (control group, PDT at continuous wave irradiation mode – CW group, PDT at pulse irradiation mode – PM group) and PDT was made. The RadachlorinⓇ photosensitizer and «Lahta-Milon» semiconductor laser (662 nm) were used. After treatment the tumor size was estimated every two days. All experiments were performed in accordance with the animal ethics guidelines.
Results
We have designed new pulse mode irradiation regimens of PDT. We have shown that antitumor efficiency of PDT at pulse irradiation mode is much better than one at standard continuous wave irradiation mode. Median survival after day of treatment was 14 days in control group, 16 days in CW group and 28 days in PM group. In PM group 5 animals had total regress of tumor and progression free survival till the end of experiment (100 days after treatment) compared with only 1 animal in CW group. Thus, we can suggest that overall survival should be much higher in PM group.
Conclusions
We have demonstrated that PDT using pulse mode irradiation regimens is much more effective that PDT using standard regimens and leads to higher progression free and overall survival in mice with CT26 colon carcinoma.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
1054 - Safety, efficacy, and pharmacokinetic (PK) profile of cosibelimab, an anti‐PD‐L1 antibody, in patients (pts) with advanced cancers
Presenter: Philip Clingan
Session: Poster Display session 1
Resources:
Abstract
4264 - A Phase I study of tinostamustine in patients (pts) with advanced solid tumours
Presenter: Alain Mita
Session: Poster Display session 1
Resources:
Abstract
3811 - Lurbinectedin (LUR) in combination with Irinotecan (IRI) in patients (pts) with advanced solid tumors
Presenter: Santiago Ponce Aix
Session: Poster Display session 1
Resources:
Abstract
1311 - A phase I study of varlitinib (VAR; ASLAN001) an oral pan-HER tyrosine kinase inhibitor (TKI) combined with mFOLFIRI chemotherapy in advanced solid tumors
Presenter: Aaron Tan
Session: Poster Display session 1
Resources:
Abstract
3482 - Phase I study of lapatinib and trametinib in patients with KRAS mutant colorectal, non-small cell lung and pancreatic cancer
Presenter: Sanne Huijberts
Session: Poster Display session 1
Resources:
Abstract
4749 - Pharmacokinetic (PK) and updated survival data from the Canadian Cancer Trials Group IND.226 study of durvalumab ± tremelimumab in combination with platinum-doublet chemotherapy
Presenter: Desiree Hao
Session: Poster Display session 1
Resources:
Abstract
4530 - A Phase 2a clinical trial combining ALRN-6924 and palbociclib for the treatment of patients with tumors harboring wild-type p53 and MDM2 amplification or MDM2/CDK4 co-amplification
Presenter: Funda Meric-Bernstam
Session: Poster Display session 1
Resources:
Abstract
4280 - Updated Efficacy and Safety of Entrectinib in Patients with NTRK Fusion-Positive Tumors: Integrated Analysis of STARTRK-2, STARTRK-1 and ALKA-372-001
Presenter: Christian Rolfo
Session: Poster Display session 1
Resources:
Abstract
6144 - An international randomized cross-over bio-equivalence study of oral paclitaxel + HM30181 compared with weekly intravenous (IV) paclitaxel in patients with advanced solid tumors
Presenter: Christopher Jackson
Session: Poster Display session 1
Resources:
Abstract
4228 - Clinical Evaluation of Drug-Eluting Bead Transcatheter Arterial Chemoembolization(D-TACE) versus Conventional TACE in Treatment of unresectable Hepatocellular Carcinoma
Presenter: Yi Chen
Session: Poster Display session 1
Resources:
Abstract