ARNT and neoplasm: Therefore, the cross-talk between HIF-1α and AhR provides a system for immune modulation based on the bioenergetic needs of specific cell subsets.47 Moreover, dimerization of HIF-1β or AhR nuclear translocator with HIF-1α is involved in various aspects of carcinogenesis, including proliferation and survival under hypoxic conditions: to this end, Choi et al.48 have recently demonstrated suppression of tumour cell invasion and migration in HIF-1β-silenced HCC cell lines, suggesting that HIF-1β expression is essential for tumour cell survival under hypoxic conditions in HCC.