Enhancement of Antitumor Effects of a New Boron Compound Combined with Ultrasound on the Mouse Ascites Tumor

Abstract

The use of ultrasound in therapeutic medicine is a developing field. The action of many anticancer agents can be improved with the use of ultrasonic exposure either in vitro or in vivo. Boron-based compounds have shown promising results as chemotherapeutic agents in specific forms of cancer. We synthesized a new boron compound of chloroacetohydroxamic acid, 2-hydroxyamino-oxoethylborate (HAOB). HAOB was used in combination with ultrasound (US) at a frequency of 25 KHz, and inhibitory effects on the growth of mouse ascites tumours were monitored by observing survival time, tumour growth, cell viability and DNA synthesis of treated Ehrlich ascites carcinoma (EAC) cells. 5-Fluorouracil (5-FU) was used as a positive control. The results indicated that HAOB alone produced significant antitumor action whereas combination of US with HAOB or 5-FU produced an extra antitumor action when compared to the actions of HAOB or 5-FU used alone.

In vivo Efficacy of HIFU (High Intensity Focused Ultrasound) on Mice with Ehrlich Ascites Carcinoma

“…The models of colon and pancreatic adenocarcinoma cells were especially used in the experimental studies conducted on HIFU in the literature (2,14,18). However, in this study, it was not possible to obtain a solid tumor as a result of the inoculation performed using the colon cancer cell line [HT-29 (HTB-38™)].…”

“…The pathological events that occur during this time period results in the conversion of sound energy to light energy, which is defined as "sonoluminescence," and this phenomenon can be observed under USG. When HIFU was used in the study, the continuation of treatment until tumorous tissues became hyperechoic is based on this mechanism (18). During the experiment, a characteristic appearance under USG was obtained in subjects who underwent HIFU treatment.…”

“…Some studies suggest that light microscopy may not be sufficient in determining necrosis, so electron microscopy may be required (18). Although it is shown that HIFU-induced cell death is mostly caused by necrosis resulting from heat, apoptosis is considered to be the primary mechanism responsible for cell death in necrosis due to hyperthermia (26).…”