Aryl Hydrocarbon Receptor Mediates Cell Proliferation Enhanced by Benzo[a]pyrene in Human Lung Cancer 3D Spheroids.

The aryl hydrocarbon receptor (AhR) is activated by the ligand, benzo[a]pyrene (B[a]P), a component of smoke that is implicated in lung carcinogenesis in humans. However, the role of B[a]P and AhR in lung cancer malignancy is not well known. In this study, we analyzed the effects of B[a]P and AhR in the 3 D spheroids of human lung cancer cells .

The regulation mechanism of AhR activated by benzo[a]pyrene for CYP expression are different between 2D and 3D culture of human lung cancer cells.

Most of cytochrome P450 (CYP) expressions are regulated by nuclear receptors. The regulation pathways of transcription are activated by binding of the ligand to the receptor. Many combination of CYPs and nuclear receptors in transcriptional regulation have been reported.

Differentiated embryonal rhabdomyosarcoma in a cow.

An embryonal rhabdomyosarcoma was found in the pleura of a 2-year-old Holstein cow after first delivery. The most predominant cells in the tumor were relatively small in size, but considerable numbers of more differentiated cells of larger sizes mingled with the small cells. The most differentiated cells were characterized by multinucleation, abundant cytoplasm containing cross-striated fibrils, intense immunoreactivity for desmin, and weak or negative reactivity for vimentin.