A diode laser therapy for cancer cells in vitro and in vivo

Dissertant

Salih, Raja Sayhud Abbas

Thesis advisor

Yusuf, Iman H.
Mahmud, Ali S.

Comitee Members

Araak, Jawad K.
al-Dabhawi, Ahmad Hamid
al-Janabi, Abd al-Hadi M.

University

University of Baghdad

Faculty

The Institute of Laser for Postgraduate Studies

University Country

Iraq

Degree

Master

Degree Date

2012

English Abstract

The aim of this study was to evaluate Photodynamic therapy PDT using diode laser at wavelength (650 nm) with methylene blue MB as a photosensitizer in vitro and in vivo .

The cytotoxic effect of PDT with MB was investigated in vitro on murine leiomyosarcoma (L20B) and rhabdomyosarcoma (RD ) cell lines .In this study the cell lines seeded separately ,they were divided into two main groups : control group (A) left without any treatment while the second group (B) group of test which subdivided into seven groups (B1,B2 and B3) which treated with MB diluted with MEM to final concentrations (1% ,0.1% and 0.01%) respectively then irradiated with laser for different exposure times (10,20 and 30 min) for each group, the groups (B4 ,B5 and B6 ) treated with MB diluted with MEM (1% ,0.1% and 0.01%) only without irradiation and group( B7 ) irradiated with laser without MB.

The results showed maximum growth inhibition rate(80.46%) for (L20B) cell line and (74.16%) for (RD )cell line for group of PDT ( B1) which photosensitized with 1%MB then irradiated with diode laser at power density 0.052 W\cm2 for 30 min exposure time ,while the results of group B7 showed a minimum growth inhibition rate (10.78%) for (L20B) cell line and (12.35%) for (RD )cell line .

To evaluate apoptosis after PDT , DNA fragmentation percentages for L20B and RD cell lines were calculated for each exposure time using MB 1% only + diode laser at power density 0.023 W/cm2.

The results of L20B cell line revealed that group (T2) treated with PDT 1%MB+Laser at (30 min of exposure time) showed significant increase in the mean value of DNA fragmentation percentage reaching (82.77%)when compared with control group (T1) which was III (74.48%),while in RD cell line group (T2) treated with PDT 1%MB+Laser at (30 min of exposure time) showed significant increase (80.70%) when compared with control group (T1) which was (74.45%) .

PDT using diode laser at 0.023 W/cm2 power density may induce apoptosis due to inhibition of DNA synthesis.

In the in vivo study, 60adult female BALB/c mice were used.

They were divided into two main groups control groups G1 control negative(-ve ) tumor free mice, G2 control positive (+ve ) tumor bearing mice, and experimental groups (G3,G4 and G5 )to study the tumor volume , tumor growth inhibition rate (GIR), cytogenetical, hematological and histopathological changes after PDT of mammary adenocarcinoma bearing mice, then compared with groups G6,G7and G8 (tumor bearing mice) treated with MB (1% ,0.1% and 0.01%) only, group G9 tumor free mice injected S/C with MB (1%) and group G10 tumor bearing mice treated with laser only.

The results showed a significant decrease of tumor volume for group (G3,G4 and G5 )during the five weeks of experiment with increase in the GIR reaching to ( 96.27 % )for G3at the 5th week after PDT using diode laser (650 nm )at power density 0.052W\cm2 after intratumoral injection of 1% MB diluted with normal saline , significant increase in the growth inhibition rate for PDT groups( G3,G4 and G5 )in comparison with G2 control (+ve ).

At the last week of the experiment complete tumor eradication occurred for PDT groups and the tumor does not seen macroscopically, tumor growth was notably inhibited in comparison with control G2 ,groups treated only MB and group treated with laser only.

In cytogenetic study ,the results of mitotic index (MI) and blast index (BI) showed significant increase in (MI) and (BI) values in groups treated with PDT G3 , the results showed significant decrease in these IV values for groups of control G2 , groups treated with MB without laser and group treated with laser only.

Blood parameters showed a significant increase in Hb, PCV, WBCs count, RBCs count in groups treated with ( PDT), while these parameters showed significant decrease in control group.

In case of differential count the results showed lymphocytes and monocytes numbers have significant increase in groups treated with (PDT), while neutrophils number increase in group of control (+ve ).

Histopathological sections in control group showed the presence of tumor growth characterized by formation of acinar like structures, with pleomorphic tumor cells and hyperchromatic nuclei with high numbers of mitotic figures.

Histopathological sections in groups of tumor-bearing female mice, treated with 1% MB+ Laser showed absence of tumor mass replaced by fibrous connective tissue, mononuclear cell infiltration and hyperplasia of lymphoid tissue of white pulp of the spleen .

Finally the conclusion was obtained from this study that diode laser induce the best photodynamic therapeutic effect on cancer cells in vitro and in vivo after cells photosensitization with MB 1% and 30 min of exposure time.

Main Subjects

Physics
Medicine

Topics

• Cancer
• Lasers

No. of Pages

142

Table of Contents

• APA
• MLA
• AMA

Language

English

Data Type

Arab Theses

Record ID

BIM-606614