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The number of people afflicted with oral carcinoma in Japan has increased in recent years. Although preoperative neoadjuvant therapy with cisplatin and 5-fluorouracil are performed, chemotherapeutic response varies widely among the patients. With the aim of establishing novel indices to predict the therapeutic response to chemotherapy, we investigated the relationship between morphological features of pre-treatment oral carcinoma nuclei and the chemotherapeutic response using quantifying morphology of cell nuclei in pathological specimen images. We measured 4 morphological features of the nucleus of oral squamous cell carcinoma cases classified by the response to chemotherapy: No Change (NC) group, Partial Response (PR) group and Complete Response (CR) group. Furthermore, we performed immunohistochemical staining for p53 and Ki67 and calculated their positive rates in cancer tissues. Compactness and symmetry of the nucleus were significantly higher and nuclear edge response was significantly lower in cancer cells with lower chemotherapeutic responses compared high chemotherapeutic responders. As for positive rates of p53 and Ki67, there were no significant differences between any of the response groups. Morphological features of cancer cell nuclei in pathological specimens are sensitive predictive factors for the chemotherapeutic response to oral squamous cell carcinoma.

Though special AT-rich sequence-binding protein 2 (SATB2) is reported as a transcriptional regulator of skeletal development and osteogenic differentiation, the underlying mechanism of SATB2 is not fully understood. Herein, we report that SATB2 is localized to the mitotic microtubules, the centrosome, and midbodies in mitotic cells with alpha-tubulin. Moreover, siRNA-mediated disruption of SATB2 in H460 cells caused the defect of nuclear morphology and multinucleate cells. SATB2 siRNA knockdown reduced the viability and downregulated the CDK2 expression in SKOV3 cells. Consistently, cell cycle analysis demonstrated that the silencing of SATB2 induced cell-cycle G1 arrest. Furthermore, proteosomal inhibitor MG132 treatment rescued the downregulation of CDK2 in SATB2-silenced SKOV3 cells. Taken together, our findings suggest that SATB2 regulates the mitosis of cell cycle and affects G1 cell cycle via interaction with CDK2.

Photodynamic therapy (PDT) involves the administration and activation of photosensitizing reagents in cancer tissues to induce cytotoxicity. Here we examined the effects of 5-5- (4-N, N-diacetoxylphenyl)-10,15,20- tetraphenylporphyrin (DTPP) -mediated PDT on cell morphology, viability, cell cycle, and cytotoxicity in a murine lung adenocarcinoma cell line. LA795 murine lung adenocarcinoma cell line was used in the study, with cellular uptake of DTPP being quantified by a UV-visible spectrophotometer. The subcellular localization of DTPP was detected by confocal laser scanning microscopy, alteration of cell morphology after PDT was observed by an inverted light microscope, and late-stage apoptosis was examined by terminal dUTP nick end labeling (TUNEL) . The effects of influencing factors on cytotoxicity of PDT in LA795 cells was investigated with varying concentrations of DTPP, energy densities, power densities, and antioxidants by 3- (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Effects of PDT on cell cycle and plasma membrane integrity were studied by flow cytometry analysis. The uptake of DTPP by LA795 cells reached maximum after incubation for 24 h. Confocal laser scanning microscopy showed that DTPP was mainly in the mitochondrion, and slight localization was detected in the lysosomes. Cellular inhibitory effects increased with increased irradiation dose and DTPP concentration, while unactivated DTPP had low toxicity. Flow cytometry analysis revealed that DTPP-PDT-treated cells showed S phase arrest. Cell membrane damage initiation, repair, and irreversible damage were observed at 2, 4, and 5 h after DTPP-PDT , respectively. Together, our results demonstrated cell apoptosis, compromised viability, and cell cycle S phase arrest of LA795 in response to DTPP-PDT , while no effect on the lung cancer cells was observed with irradiation or photosensitizer treatment alone.

Methamphetamine (METH) is a highly addictive drug causing neurodegenerative diseases. METH has been known to be neurotoxic by inducing oxidative stress, free radical, and pro-inflammatory cytokines. Previous studies have shown that METH could induce neuron and glial cell death, especially inducing glial cell-mediated neurotoxicity that plays a critical role in stress-induced central nervous system damage. Therefore, the aim of the present study is to explore the mechanisms of METH-induced cell death in the glial cell. METH-induced glial cells death is mediated via mitochondrial damage pathway. METH activates the upregulation of the Bax, cytochrome c, cleavage caspase 9 and 3 proteins, and downregulation of Bcl-XL protein in cascade. Pretreatment with melatonin, a neurohormone secreted by the pineal gland, effectively reduced glial cell death. Moreover, melatonin increased the Bcl-XL/Bax ratio but reduced the level of cytochrome c, cleavage caspase 9 and 3 proteins. Therefore, these results demonstrated that melatonin could reduce the cytotoxic effect of METH by decreasing the mitochondrial death pathway activation in glial cells. This outcome suggests that melatonin might be beneficial as the neuroprotection in neurodegenerative diseases caused by METH or other pathogens.

Human pluripotent stem cell-derived cardiomyocytes (hPSC-CM) are being investigated as a new source of cardiac cells for drug safety assessment. We developed a novel scalable high content microscopy-based method for the detection of cell death in hPSC-CM that can serve for future predictive in vitro cardio-toxicological screens. Using rat neonatal ventricular cardiomyocytes (RVNC) or hPSC-CM, assays for nuclear remodelling, mitochondrial status, apoptosis and necrosis were designed using a combination of fluorescent dyes and antibodies on an automated microscopy platform. This allowed the observation of a chelerythrine-induced concentration-dependent apoptosis to necrosis switch and time-dependent progression of early apoptotic cells towards a necrotic-like phenotype. Susceptibility of hPSC-CM to chelerythrine-stimulated apoptosis varied with time after differentiation, but at most time points, hPSC-CM were more resistant than RVNC. This simple and scalable humanized high-content assay generates accurate cardiotoxicity profiles that can serve as a base for further assessment of cardioprotective strategies and drug safety.