Structured illumination microscopy and its new developments

Optical microscopy allows us to observe the biological structures and processes within living cells. However, the spatial resolution of the optical microscopy is limited to about half of the wavelength by the light diffraction. Structured illumination microscopy (SIM), a type of new emerging super-resolution microscopy, doubles the spatial resolution by illuminating the specimen with a patterned light, and the sample and light source requirements of SIM are not as strict as the other super-resolution microscopy. In addition, SIM is easier to combine with the other imaging techniques to improve their imaging resolution, leading to the developments of diverse types of SIM. SIM has great potential to meet the various requirements of living cells imaging. Here, we review the recent developments of SIM and its combination with other imaging techniques

Discovery of Selective Histone Deacetylase 6 Inhibitors Using the Quinazoline as the Cap for the Treatment of Cancer

Novel selective histone deacetylase 6 (HDAC6) inhibitors using the quinazoline as the cap were designed, synthesized, and evaluated for HDAC enzymatic assays. <i>N</i>-Hydroxy-4-(2-methoxy-5-(methyl­(2-methylquinazolin-4-yl)­amino)­phenoxy)­butanamide, <b>23bb</b>, was the most potent selective inhibitor for HDAC6 with an IC₅₀ of 17 nM and showed 25-fold and 200-fold selectivity relative to HDAC1 and HDAC8, respectively. In vitro, <b>23bb</b> presented low nanomolar antiproliferative effects against panel of cancer cell lines. Western blot analysis further confirmed that <b>23bb</b> increased acetylation level of α-tubulin in vitro. <b>23bb</b> has a good pharmacokinetic profile with oral bioavailability of 47.0% in rats. In in vivo efficacy evaluations of colorectal HCT116, acute myelocytic leukemia MV4-11, and B cell lymphoma Romas xenografts, <b>23bb</b> more effectively inhibited the tumor growth than SAHA even at a 4-fold reduced dose or ACY-1215 at the same dose. Our results indicated that <b>23bb</b> is a potent oral anticancer candidate for selective HDAC6 inhibitor and deserves further investigation