Erratum

This article refers to:

Cytotoxic C-Methylated Chalcones from Syzygium samarangense.

In the article, Cytotoxic C-Methylated Chalcones from Syzygium samarangense., by E.C. Amor et al., published in Pharmaceutical Biology, 45(10): 777–783, the following revisions have been made:

The IC₁₂ of compound 2 against the RAD52 mutant strain should be 252 μ M while that of the positive control, streptonigrin should be 0.008 μ M. In addition, compound 2 was not cytotoxic against the LF15 wild-type strain that is why it was concluded that it exhibited selective cytotoxicity towards the mutant strain.

Table 3 should be modified according to the table below, which indicates the correct IC₅₀ values of the compounds and the positive control. The IC₅₀ values obtained are rough estimates that are based on two concentrations, 50 μ.g/mL and 5 μ.g/mL, due to limited sample availability.

Table 1 Fractional survival and IC₅₀ values of compounds 1–5 against CHO-AA8, MCF-7 and SKBR-3 cell lines.

	CHO-AA8		MCF-7		SKBR-3
Test compounds	Fractional survival^a.	IC50 (μ M)	Fractional survival^a.	IC50 (μ M)	Fractional survival^a.	IC50 (μ M)
1^b.	0.456 ± 0.011	Not done	0.488 ± 0.013	Not done	0.335 ± 0.080	Not done
2^b.	0.101 ± 0.002	80.547 ± 0.815	0.052 ± 0.001	1.463 ± 0.007	0.310 ± 0.003	12.779 ± 0.057
3^b.	0.575 ± 0.002	21.856 ± 0.005	0.227 ± 0.027	20.180 ± 0.237	0.394 ± 0.045	12.722 ± 0.268
4^c.	Not active		0.195 ± 0.023	Not done	Not active
5^c.	0.033 ± 0.001	13.013 ± 0.170	0.054 ± 0.002	9.337 ± 0.077	0.075 ± 0.008	7.377 ± 0.070
Doxorubicin	—	0.288 ± 0.002	—	0.260 ± 0.003	—	0.028 ± 0.001

^a. n = 4

^b. active dose of 50 μ.g/mL

^c. active dose of 5 μ.g/mL

The concentrations at which compounds 2 and 5 are cytotoxic against normal and breast cancer cells should be 167.8 μ M and 16.7 μ M, respectively. Compounds 1 and 3 showed slight toxicity against normal and breast cancer cells at a concentration of 167.8 μ M while 4 is cytotoxic at 17.5 μ M.

The chalcone counterpart of dihydrochalcone 4 is compound 3 and not compound 1.