PIMT Binding to C-Terminal Ala459 of CAIX Is Involved in Inside-Out Signaling Necessary for Its Catalytic Activity

IL-22 regulates MASTL expression in intestinal epithelial cells

Microtubule-associated serine-threonine kinase-like (MASTL) has recently been identified as an oncogenic kinase given its overexpression in numerous cancers. Our group has shown that MASTL expression is upregulated in mouse models of sporadic colorectal cancer and colitis-associated cancer (CAC). CAC is one of the most severe complications of chronic inflammatory bowel disease (IBD), but a limited understanding of the mechanisms governing the switch from normal healing to neoplasia in IBD underscores the need for increased research in this area. However, MASTL levels in patients with IBD and its molecular regulation in IBD and CAC have not been studied. This study reveals that MASTL is upregulated by the cytokine interleukin (IL)-22, which promotes proliferation and has important functions in colitis recovery; however, IL-22 can also promote tumorigenesis when chronically elevated. Upon reviewing the publicly available data, we found significantly elevated MASTL and IL-22 levels in the biopsies from patients with late-stage ulcerative colitis compared with controls, and that MASTL upregulation was associated with high IL-22 expression. Our subsequent in vitro studies found that IL-22 increases MASTL expression in intestinal epithelial cell lines, which facilitates IL-22-mediated cell proliferation and downstream survival signaling. Inhibition of AKT activation abrogated IL-22-induced MASTL upregulation. We further found an increased association of carbonic anhydrase IX (CAIX) with MASTL in IL-22-treated cells, which stabilized MASTL expression. Inhibition of CAIX prevented IL-22-induced MASTL expression and cell survival. Overall, we show that IL-22/AKT signaling increases MASTL expression to promote cell survival and proliferation. Furthermore, CAIX associates with and stabilizes MASTL in response to IL-22 stimulation.NEW & NOTEWORTHY MASTL is upregulated in colorectal cancer; however, its role in colitis and colitis-associated cancer is poorly understood. This study is the first to draw a link between MASTL and IL-22, a proinflammatory/intestinal epithelial recovery-promoting cytokine that is also implicated in colon tumorigenesis. We propose that IL-22 increases MASTL protein stability by promoting its association with CAIX potentially via AKT signaling to promote cell survival and proliferation.

Carbonic Anhydrase and Biomarker Research: New Insights

Carbonic anhydrase (CA) is a widespread metalloenzyme with eight genetically distinct families catalyzing the reversible hydration of CO₂ to HCO₃^- and H⁺ [...].

Synthesis and Inhibition Activity Study of Triazinyl-Substituted Amino(alkyl)-benzenesulfonamide Conjugates with Polar and Hydrophobic Amino Acids as Inhibitors of Human Carbonic Anhydrases I, II, IV, IX, and XII

Primary sulfonamide derivatives with various heterocycles represent the most widespread group of potential human carbonic anhydrase (hCA) inhibitors with high affinity and selectivity towards specific isozymes from the hCA family. In this work, new 4-aminomethyl- and aminoethyl-benzenesulfonamide derivatives with 1,3,5-triazine disubstituted with a pair of identical amino acids, possessing a polar (Ser, Thr, Asn, Gln) and non-polar (Ala, Tyr, Trp) side chain, have been synthesized. The optimized synthetic, purification, and isolation procedures provided several pronounced benefits such as a short reaction time (in sodium bicarbonate aqueous medium), satisfactory yields for the majority of new products (20.6-91.8%, average 60.4%), an effective, well defined semi-preparative RP-C18 liquid chromatography (LC) isolation of desired products with a high purity (>97%), as well as preservation of green chemistry principles. These newly synthesized conjugates, plus their 4-aminobenzenesulfonamide analogues prepared previously, have been investigated in in vitro inhibition studies towards hCA I, II, IV and tumor-associated isozymes IX and XII. The experimental results revealed the strongest inhibition of hCA XII with low nanomolar inhibitory constants (Kis) for the derivatives with amino acids possessing non-polar side chains (7.5-9.6 nM). Various derivatives were also promising for some other isozymes.