Introduction: Background: Lactobacillus and Bifidobacterium species are among the probiotics discussed due to
their anti-cancer effects in the treatment of colorectal and breast cancers in recent studies. The aim
of this study was to investigate the anticancer effect of Familact, a commercial probiotic capsule
containing seven bacterial strains (L. casei, L. acidophilus, L. rhamnosus, L. bulgaricus, B. breve, B.
longum and Streptococcus thermophilus).
Methods: Various cancer cell lines including Caco-2, HT-29, T47D and normal cell line L929 were
treated with different concentrations of Familact. Using MTT assay, the cytotoxicity effect was
investigated for each cell line and then flow cytometry analysis of apoptosis was evaluated.
Results: Cytotoxicity Effect of Familact
The cytotoxic activity of Familact on L929,
Caco-2, HT-29, and T47D cell lines was
investigated using MTT assay. After treatment with
serial concentrations of the drug for 48 h, the 50%
inhibitory concentration (IC50) was assessed.
Familact inhibited cell viability of HT-29, Caco-
2, T47D and L929 in a dose-dependent manner with
an IC50 value of 37.4 ± 4.25, 75.41 ± 1.85, 75 ±
9.69 and 78.45 ± 6.8 μg/ml, respectively (Figure 1).
Overall, Familact exhibited remarkable cytotoxicity
to HT-29 while other aforementioned cell lines
experienced moderate toxicity towards this drug.
Flow Cytometric Analysis of Apoptosis
The effect of Familact on induced apoptosis in
L929, Caco-2, HT-29 and T47D cells was evaluated
by Annexin V-FITC and PI staining. The flow
cytometry analysis showed that in L929 normal
cells, exposure to Familact increased the percentage
of late apoptotic cells in comparison to untreated
control cells while HT-29 cells experienced a two-
fold increase in late apoptotic cell death (P<0.01).
In the case of Caco-2 and T47D cells, Familact was
less effective in this regard, implying different
mechanisms of cell death may be involved (Figure2)
Conclusion: Promising results would be obtained using this
probiotic complex as complementary therapy in the
treatment of colon cancer. In addition, for the
prevention and treatment of cancer, the discovery of
new probiotic bacteria with anti-cancer properties
seems necessary.
Keywords: Apoptosis, Breast Cancer, Colorectal Cancer, Familact, Prebiotic, Probiotics.