Inhibition of mouse colon cancer growth following immunotherapy with a fraction of hydatid cyst fluid

BACKGROUND

Hydatid cyst is the larval stage of the tape worm Echinococcus granulosus which is located in human and livestock viscera. There are some scientific evidences indicating that parasitic infections induce antitumor activity against certain types of cancers. In this study, the effects of a fraction of hydatid cyst fluid on colon cancer tumor in BALB/c mice were investigated.

MATERIALS AND METHODS

In this experimental work six groups of mice were challenged with mouse colon cancer cells. 5 days later when the sign of tumor growth in mice was seen, group 1-4 were injected with hydatid cyst fluid, the 78 kDa fraction, live protoscolices and BCG respectively. Group five was injected with alum alone and the sixth group left intact without any injection. The size of the tumor was measured and compared in all groups. Then blood samples of mice were evaluated for serum cytokine levels.

RESULT

In mice injected with hydatid cyst antigens especially a fraction of hydatid cyst fluid, tumor size was smaller than the that of control groups and the difference of tumor size in cases and control groups was statistically significant.

CONCLUSION

The results of this study showed that injection of mice with a fraction of hydatid cyst fluid significantly inhibits the growth of mouse colon cancer and this inhibition may be related to effect of immune response to these antigens.

Identifying the Most Effective Hydatid Cyst Fluid Fraction for Anticancer Vaccination of 4T1 Breast Tumor-Bearing Mice

Background:

The hydatid cyst fluid antigens have high homology with cancer cell antigens and also exhibit considerable immunogenicity. Therefore, their utilization for cancer immunization can cause an effective antitumor immune response. However, the main challenge is identifying the most effective antigens for this purpose.

Methods:

Hydatid cyst fluid fractions including the glycolipid fraction, glycoprotein fraction, 78 kDa fraction, and antigen B fraction were prepared. Then, the BALB/c mice were immunized against different antigens and, subsequently, 4T1 cells were subcutaneously implanted. The tumors' growth, metastasis, and tumor-bearing mice survival were assessed in different immunized groups. In addition, IL-2, IL-4, IFN-γ, and TNF-α serum levels were estimated to evaluate the immune system response.

Results:

BALB/c mice immunization against the complete hydatid cyst fluid antigens exhibited more significant inhibition of the tumors' growth and metastasis and increase of tumor-bearing mice survival in comparison with its derived fractions. However, the 78 kDa fraction exhibited the best results according to the same factors in comparison with all the prepared fractions.

Conclusions:

The 78 kDa fraction of the hydatid cyst fluid was the most effective fraction of hydatid cyst fluid for immunization against 4T1 breast tumors.