Circular RNAs (circRNAs) which were once considered as "junk" are now in the spotlight as a potential player in regulating human diseases, especially cancer. With the development of high throughput technologies in recent years, the full potential of circRNAs is being uncovered. CircRNAs possess some unique characteristics and advantageous properties that could benefit medical research and clinical applications. CircRNAs are stable with covalently closed loops that are resistant to ribonucleases, have disease stage-specific expressions and are selectively abundant in different types of tissues. Interestingly, the presence of circRNAs in different types of treatment resistance in human cancers was recently observed with the involvement of a few key pathways. The activation of certain pathways by circRNAs may give new insights to treatment resistance management. The potential usage of circRNAs from this aspect is very much in its infancy stage and has not been fully validated. This mini-review attempts to highlight the possible role of circRNAs as regulators of treatment resistance in human cancers based on its intersection molecules and cancer-related regulatory networks.

Flavokawains are chalcones that can be found in the root extracts of the kava-kava (Piper methysticum) plant. Flavokawain A and flavokawain B are known to possess potential anti-inflammation and anti-cancer activities. Nevertheless, the effects of both these compounds on the normal function of the host have not been studied. There is a need to find agents that can enhance the functionality of the immune system without disturbing the homeostatic balance. This study aimed to determine the toxicity and immunomodulatory effects of flavokawain A and flavokawain B on Balb/c mice. Several assays were conducted, the MTT viability assay, cytokine detection (IL-2 and TNF-), immunophenotyping of important immune markers, serum biochemical analysis and detection of nitric oxide levels. Based on our results, flavokawain A and B did not cause mortality and all mice were observed normal after the treatment period. Both flavokawains stimulated splenocyte proliferation, the secretion of IL-2 and TNF-α and raised the population of T cell subsets without significantly altering the level of several serum biochemical parameters. Overall, flavokawain A and B could serve as potential immune-modulator drugs without causing any toxicity, however further in vivo evidence is needed.