**3. Results of investigations**

## **3.1 Cell pharmacokinetics**

In the time interval from 1 to 12 h after the BSH administration relatively high boron content was in subcellular structures of tumor tissue. BSH was preferably accumulated in nuclei and mitochondria. (Table 1). These data suggest the BNCT with BSH might be more effective during time interval from 6 to 12 h after drug administration.


Table 1. 10В concentration in subcellular fractions of B-16 melanoma and liver in С57Bl/6 mice after BSH administration [10В µg/g]

In the time interval from 24 to 48 h after the KUG-1 administration maximal boron content was in nuclear fraction. This concentration exceeded necessary and sufficient concentration for successful NCT. Boron content in other subcellular fractions was sufficient for therapeutic efficacy of NCT. (Table 2). Therefore boron subcellular distribution had confirmed clinical perspectives of KUG-1.


Table 2. 10В concentration in subcellular fractions of B-16 melanoma and liver in С57Bl/6 mice after KUG-1 administration [10В µg/g]

Binary Radiotherapy of Melanoma - Russian Research Results 133

On the base of obtained results of МТТ-test and clonogenic test curves of dependence " part

 **X-rays + 0.0125М Gd-DTPA**

**10 15 20 25 30 35 40**

**X-rays**

**X-rays dose,Gy**

Fig. 4. Cell survival for control and experimental groups (MTT-test data) at 3rd, 5th and

MTT-test data had shown equal parts of survived cells in both groups on 3-rd day. On 5-th day part survived cells in experimental group was essentially low and was retained at this level to 7-th day. RGG-test data had shown (Fig. 5) practically complete suppression of cell growth in experimental group even at 10 Gy. In control group significant quantity of cell

**Survival,%**

**5 days**

 **X-rays**

**5 10 15 20 25 30 35 40**

**X-rays dose,Gy**

 **X-rays + 0.00125M Gd-DTPA**

of survived cells – exposition dose" were constructed. (Fig. 4 and Fig. 5).

**3.3 In vitro studies of photon capture therapy** 

 **X-rays**

**X-rays + 0.00125М Gd-DTPA**

**5 10 15 20 25 30 35 40**

**X-rays dose,Gy**

**10**

**20**

**30**

**Survival**,**%**

**40**

**7 days**

7th days

colonies were observed.

**Survival,%**

**3 days**
