World J Oncol

World Journal of Oncology, ISSN 1920-4531 print, 1920-454X online, Open Access

Article copyright, the authors; Journal compilation copyright, World J Oncol and Elmer Press Inc

Journal website http://www.wjon.org

Original Article

Volume 5, Number 4, August 2014, pages 155-165

Significance of Fractionated Administration of Thalidomide Combined With γ-Ray Irradiation in Terms of Local Tumor Response and Lung Metastasis

Figure 1. Cell survival curves for the total cell population from B16-BL6 tumors irradiated with γ-rays following single or two intraperitoneal administrations of thalidomide in combination with nicotinamide treatment or mild temperature hyperthermia (MTH) on day 18 after tumor cell inoculation. Circles: γ-ray irradiation only; squares: γ-ray irradiation with nicotinamide treatment; triangles: γ-ray irradiation with MTH. Bars represent standard errors (n = 6).

Figure 2. Dose response curves of the net micronucleus frequency for total (open symbols: left panels) and quiescent (solid symbols: right panels) cell populations from B16-BL6 tumors irradiated with γ-rays following single or two intraperitoneal administrations of thalidomide in combination with nicotinamide treatment or mild temperature hyperthermia (MTH) on day 18 after tumor cell inoculation. Circles: γ-ray irradiation only; squares: γ-ray irradiation with nicotinamide treatment; triangles: γ-ray irradiation with MTH. Bars represent standard errors (n = 6).

Figure 3. Counted numbers of macroscopic metastases in the lung on day 35 after tumor cell inoculation as a function of the dose of γ-ray irradiation following the single or two intraperitoneal administrations of thalidomide in combination with nicotinamide treatment or mild temperature hyperthermia (MTH) on day 18 after tumor cell inoculation. Circles: γ-ray irradiation only; squares: γ-ray irradiation with nicotinamide treatment; triangles: γ-ray irradiation with MTH. Bars represent standard errors (n = 6).

**Table 1.** Surviving Fraction and Micronucleus Frequency at 0 Gy
	Without thalidomide	With thalidomide (once)	With thalidomide (twice)
^aMean ± standard error (n = 6). Q cells showed significantly higher micronucleus frequencies than the total cell population under each set of conditions (P < 0.05). Thalidomide administration resulted in significantly lower surviving fractions and significantly higher micronucleus frequencies in both the total and Q cell populations than absolutely no treatment (P < 0.05).
Surviving fraction at 0 Gy (%)
Without nicotinamide or mild temperature hyperthermia	84.4 ± 8.2^a	60.0 ± 5.5	69.8 ± 6.3
With nicotinamide	81.4 ± 7.3	55.0 ± 4.3	60.0 ± 5.7
With mild temperature hyperthermia	83.5 ± 8.7	56.0 ± 5.9	60.5 ± 5.3
Micronucleus frequency at 0 Gy
Total tumor cell population
Without nicotinamide or mild temperature hyperthermia	0.050 ± 0.005	0.081 ± 0.008	0.070 ± 0.007
With nicotinamide	0.057 ± 0.006	0.090 ± 0.008	0.082 ± 0.008
With mild temperature hyperthermia	0.054 ± 0.005	0.085 ± 0.009	0.080 ± 0.008
Quiescent cells
Without nicotinamide or mild temperature hyperthermia	0.077 ± 0.007	0.102 ± 0.01	0.094 ± 0.009
With nicotinamide	0.084 ± 0.008	0.11 ± 0.01	0.101 ± 0.01
With mild temperature hyperthermia	0.081 ± 0.008	0.103 ± 0.01	0.099 ± 0.009

Table 1. Surviving Fraction and Micronucleus Frequency at 0 Gy

Without thalidomide

With thalidomide (once)

With thalidomide (twice)

^aMean ± standard error (n = 6). Q cells showed significantly higher micronucleus frequencies than the total cell population under each set of conditions (P < 0.05). Thalidomide administration resulted in significantly lower surviving fractions and significantly higher micronucleus frequencies in both the total and Q cell populations than absolutely no treatment (P < 0.05).

Surviving fraction at 0 Gy (%)

Without nicotinamide or mild temperature hyperthermia

84.4 ± 8.2^a

60.0 ± 5.5

69.8 ± 6.3

With nicotinamide

81.4 ± 7.3

55.0 ± 4.3

60.0 ± 5.7

With mild temperature hyperthermia

83.5 ± 8.7

56.0 ± 5.9

60.5 ± 5.3

Micronucleus frequency at 0 Gy

Total tumor cell population

Without nicotinamide or mild temperature hyperthermia

0.050 ± 0.005

0.081 ± 0.008

0.070 ± 0.007

With nicotinamide

0.057 ± 0.006

0.090 ± 0.008

0.082 ± 0.008

With mild temperature hyperthermia

0.054 ± 0.005

0.085 ± 0.009

0.080 ± 0.008

Quiescent cells

Without nicotinamide or mild temperature hyperthermia

0.077 ± 0.007

0.102 ± 0.01

0.094 ± 0.009

With nicotinamide

0.084 ± 0.008

0.11 ± 0.01

0.101 ± 0.01

With mild temperature hyperthermia

0.081 ± 0.008

0.103 ± 0.01

0.099 ± 0.009

**Table 2.** Enhancement Ratios^a Due to Combined Treatment With Thalidomide
	With thalidomide (once)	With thalidomide (twice)
^aThe ratio of the dose of radiation necessary to obtain each end-point without thalidomide to that needed to obtain each end-point with thalidomide. ^b Mean ± standard error (n = 6). ^{c, d}Significant differences between two values (P < 0.05).
Surviving fraction = 0.03
Total cell population	1.0 ± 0.05^{b, c}	1.25 ± 0.1^c
Net micronucleus frequency = 0.6
Total cell population	1.0 ± 0.05^d	1.2 ± 0.1^d
Quiescent cells	1.05 ± 0.1	1.1 ± 0.1

Table 2. Enhancement Ratios^a Due to Combined Treatment With Thalidomide

With thalidomide (once)

With thalidomide (twice)

^aThe ratio of the dose of radiation necessary to obtain each end-point without thalidomide to that needed to obtain each end-point with thalidomide. ^b Mean ± standard error (n = 6). ^{c, d}Significant differences between two values (P < 0.05).

Surviving fraction = 0.03

Total cell population

1.0 ± 0.05^{b, c}

1.25 ± 0.1^c

Net micronucleus frequency = 0.6

Total cell population

1.0 ± 0.05^d

1.2 ± 0.1^d

Quiescent cells

1.05 ± 0.1

1.1 ± 0.1

**Table 3.** Enhancement Ratios^a Due to Combined Treatment With Nicotinamide, or Mild Temperature Hyperthermia
	Nicotinamide	Mild temperature hyperthermia
^aThe ratio of the dose of radiation necessary to obtain each end-point without nicotinamide or mild temperature hyperthermia to that needed to obtain each end-point with nicotinamide or mild temperature hyperthermia. ^bMean ± standard error (n = 6).
Surviving fraction = 0.03
Total cell population
Without thalidomide	1.25 ± 0.1^b	1.15 ± 0.05
With thalidomide (once)	1.25 ± 0.1	1.15 ± 0.05
With thalidomide (twice)	1.05 ± 0.05	1.1 ± 0.05
Net micronucleus frequency = 0.6
Total cell population
Without thalidomide	1.2 ± 0.1	1.05 ± 0.05
With thalidomide (once)	1.3 ± 0.1	1.05 ± 0.05
With thalidomide (twice)	1.05 ± 0.05	1.1 ± 0.05
Quiescent cells
Without thalidomide	1.1 ± 0.05	1.2 ± 0.1
With thalidomide (once)	1.05 ± 0.05	1.15 ± 0.05
With thalidomide (twice)	1.1 ± 0.05	1.2 ± 0.05

Table 3. Enhancement Ratios^a Due to Combined Treatment With Nicotinamide, or Mild Temperature Hyperthermia

Nicotinamide

Mild temperature hyperthermia

^aThe ratio of the dose of radiation necessary to obtain each end-point without nicotinamide or mild temperature hyperthermia to that needed to obtain each end-point with nicotinamide or mild temperature hyperthermia. ^bMean ± standard error (n = 6).

Surviving fraction = 0.03

Total cell population

Without thalidomide

1.25 ± 0.1^b

1.15 ± 0.05

With thalidomide (once)

1.25 ± 0.1

1.15 ± 0.05

With thalidomide (twice)

1.05 ± 0.05

1.1 ± 0.05

Net micronucleus frequency = 0.6

Total cell population

Without thalidomide

1.2 ± 0.1

1.05 ± 0.05

With thalidomide (once)

1.3 ± 0.1

1.05 ± 0.05

With thalidomide (twice)

1.05 ± 0.05

1.1 ± 0.05

Quiescent cells

Without thalidomide

1.1 ± 0.05

1.2 ± 0.1

With thalidomide (once)

1.05 ± 0.05

1.15 ± 0.05

With thalidomide (twice)

1.1 ± 0.05

1.2 ± 0.05

**Table 4.** Dose-Modifying Factors for Quiescent Cells Relative to the Total Tumor Cell Population^a
	Without thalidomide	With thalidomide (once)	With thalidomide (twice)
^aThe ratio of the dose of radiation necessary to obtain each end-point in the quiescent cell population to that needed to obtain each end-point in the total tumor cell population. ^bMean ± standard error (n = 6).
Net micronucleus frequency = 0.6
γ-Rays only	1.65 ± 0.15^b	1.6 ± 0.1	1.9 ± 0.15
With nicotinamide	1.8 ± 0.15	2.0 ± 0.15	1.8 ± 0.15
With mild temperature hyperthermia	1.6 ± 0.15	1.55 ± 0.1	1.7 ± 0.1

Table 4. Dose-Modifying Factors for Quiescent Cells Relative to the Total Tumor Cell Population^a

Without thalidomide

With thalidomide (once)

With thalidomide (twice)

^aThe ratio of the dose of radiation necessary to obtain each end-point in the quiescent cell population to that needed to obtain each end-point in the total tumor cell population. ^bMean ± standard error (n = 6).

Net micronucleus frequency = 0.6

γ-Rays only

1.65 ± 0.15^b

1.6 ± 0.1

1.9 ± 0.15

With nicotinamide

1.8 ± 0.15

2.0 ± 0.15

1.8 ± 0.15

With mild temperature hyperthermia

1.6 ± 0.15

1.55 ± 0.1

1.7 ± 0.1

**Table 5.** The Numbers of Metastases From the Irradiated Tumors That Received Cytotoxic Treatment Producing a Similar Initial Local Effect^a
	Without thalidomide	With thalidomide (once)	With thalidomide (twice)
^aBased on the data shown in Fig. 4, the estimated numbers of lung metastatic nodules from local tumors that received neutron beam irradiation with or without thalidomide in combination with nicotinamide or mild temperature hyperthermia, which produced an identical surviving fraction of 0.6 as an initial effect on Fig. 1. ^bMean ± standard error (n = 6). ^c-hSignificant differences between two values (P < 0.05).
Surviving fraction = 0.03
γ-Rays only	14.1 ± 1.4^{b, c, d, e}	12.2 ± 1.3	11.9 ± 1.2
With nicotinamide	13.1 ± 1.3	11.4 ± 1.2^{c, f}	11.3 ± 1.2^{d, g}
With mild temperature hyperthermia	14.1 ± 1.4^{f, g, h}	12.2 ± 1.2	10.6 ± 1.1^{e, h}

Table 5. The Numbers of Metastases From the Irradiated Tumors That Received Cytotoxic Treatment Producing a Similar Initial Local Effect^a

Without thalidomide

With thalidomide (once)

With thalidomide (twice)

^aBased on the data shown in Fig. 4, the estimated numbers of lung metastatic nodules from local tumors that received neutron beam irradiation with or without thalidomide in combination with nicotinamide or mild temperature hyperthermia, which produced an identical surviving fraction of 0.6 as an initial effect on Fig. 1. ^bMean ± standard error (n = 6). ^c-hSignificant differences between two values (P < 0.05).

Surviving fraction = 0.03

γ-Rays only

14.1 ± 1.4^{b, c, d, e}

12.2 ± 1.3

11.9 ± 1.2

With nicotinamide

13.1 ± 1.3

11.4 ± 1.2^{c, f}

11.3 ± 1.2^{d, g}

With mild temperature hyperthermia

14.1 ± 1.4^{f, g, h}

12.2 ± 1.2

10.6 ± 1.1^{e, h}