Investigating the theragnostic potential of 131I-caerin peptide in thyroid cancer.

OBJECTIVE: Caerin is a new peptide with tumour toxicity and its uptake by tumour cells is independent of the sodium iodide symporter (NIS). Thyroid cancer is the most common cancers of endocrine malignancy. Radioiodine (131I)-refractory thyroid cancer is the most lethal subtype of the thyroid cancers and remains a clinical challenge. In the current study, we investigated the 131I radiolabeling efficiency of Caerin and the effects of Caerin, 131I-Caerin and free 131I on differentiated and undifferentiated human thyroid cancer cell lines (B-CPAP and CAL-62) in vitro. MATERIALS AND METHODS: Cell Counting Kit-8 was used to assess the cytotoxic effect of Caerin, 131I-Caerin and free 131I on B-CPAP and CAL-62 cells. Laser scanning confocal microscope was exploited to evaluate the uptake and internalization of Caerin by thyroid cancer cells. The Chloramine-T method was used to label the peptide with 131I. And the stability and water partition coefficient (Log P) of 131I-Caerin were studied. RESULTS: Our results demonstrated that Caerin and 131I-Caerin could be accumulated by B-CPAP and CAL-62 cells, resulting in killing of the thyroid cancer cells in vitro. The efficacy of 131I-Caerin is much higher than 131I, especially to undifferentiated CAL-62 cells. The results prove the feasibility of radioiodination of the 131I-Caerin via the Chloramine-T method. Moreover, the result indicate the hydrophobic 131I-Caerin was stable in 72 hours. CONCLUSION: Iodine-131-Caerin can inhibit the cell viability of thyroid cancer and hold certain promise as a theragnostic tool for human thyroid cancers.

Intracellular catalase activity instead of glutathione level dominates the resistance of cells to reactive oxygen species.

Artesunate (ARS) induced significant reactive oxygen species (ROS) generation in HepG2, HeLa, and A549 lines. However, ARS induced ROS-dependent apoptosis in HeLa and A549 cell lines but ROS-independent apoptosis in HepG2 cells. A total of 200 µM hydrogen peroxide (H2O2) significantly induced cytotoxicity in HeLa cells, while H2O2 up to 300 µM did not induce cytotoxicity in HepG2 cells, further demonstrating the strong resistance of HepG2 cells to ROS. HeLa cells had much higher basic total glutathione (T-GSH) level than HepG2 cells, while the ratio of basic reduced glutathione (GSH)/oxidized glutathione (GSSG) in HepG2 cells was nearly twice than that in HeLa and A549 cells. Inhibition of glutathione markedly enhanced H2O2- or ARS-induced cytotoxicity in HeLa and A549 cell lines but modestly enhanced the cytotoxicity of H2O2 and even did not affect the cytotoxicity of ARS in HepG2 cells. Moreover, addition of GSH remarkably prevented H2O2- or ARS-induced cytotoxicity in HeLa and A549 cell lines, further indicating the involvement of GSH in scavenging ROS in the two cell lines. HepG2 cells exhibited higher catalase activity than HeLa cells, and inhibiting catalase activity by using 3-aminotriazole (3-AT, a specific inhibition of catalase) or catalase siRNA remarkably reduced the resistance of HepG2 cells to ROS, demonstrating the key roles of catalase for the strong resistance of HepG2 cells to ROS. Collectively, catalase activity instead of glutathione level dominates the resistance of cells to ROS.

Peroxynitrite dominates sodium nitroprusside-induced apoptosis in human hepatocellular carcinoma cells.

This study aims to explore which radicals dominate sodium nitroprusside (SNP)-induced cytotoxicity in human hepatocellular carcinoma (HCC) cells (HepG2 and Hep3B). Exposure of SNP to cell medium produced abundant nitric oxide (NO), superoxide anion (O2•-), hydrogen peroxide (H2O2) and iron ions. SNP potently induced caspases activation, mitochondrial membrane permeabilization and apoptosis in HCC cells. In Hep3B cells, pretreatment with NO scavenger (PTIO) did not prevent SNP-induced cytotoxicity. However, in HepG2 cells, SNP-induced cytotoxicity was prevented significantly by pretreatment with PTIO and O2•- scavenger, and especially was almost completely blocked by pretreatment with FeTPPS (peroxynitrite scavenger). In contrast, although H2O2 scavenger potently scavenged SNP-induced H2O2 production, it did not prevent SNP-induced cytotoxicity in HepG2 cells. In addition, pretreatment with DFO (iron ions chelator) and iron-saturated DFO respectively completely prevented SNP-induced cytotoxicity in HepG2 cells. Collectively, peroxynitrite from the reaction between NO and O2•- elicited from SNP dominates the SNP-induced apoptosis of HepG2 cells, in which both iron ions and H2O2 are not involved.

Gold Nanoparticles of Diameter 13 nm Induce Apoptosis in Rabbit Articular Chondrocytes.

Gold nanoparticles (AuNPs) have been widely used in biomedical science including antiarthritic agents, drug loading, and photothermal therapy. In this report, we studied the effects of AuNPs with diameters of 3, 13, and 45 nm, respectively, on rabbit articular chondrocytes. AuNPs were capped with citrate and their diameter and zeta potential were measured by dynamic light scattering (DLS). Cell viability was evaluated by Cell Counting Kit-8 (CCK-8) assay after the rabbit articular chondrocytes were pre-incubated with 3, 13, and 45 nm AuNPs, respectively, for 24 h. Flow cytometry (FCM) analysis with annexin V/propidium iodide (PI) double staining and fluorescence imaging with Hoechst 33258 staining were used to determine the fashion of AuNPs-induced chondrocyte death. Further, 13 nm AuNPs (2 nM) significantly induced chondrocyte death accompanying apoptotic characteristics including mitochondrial damage, externalization of phosphatidylserine and nuclear concentration. However, 3 nm AuNPs (2 nM) and 45 nm (0.02 nM) AuNPs did not induce cytotoxicity in chondrocytes. Although 13 nm AuNPs (2 nM) increased the intracellular reactive oxygen species (ROS) level, pretreatment with Nacetyl cysteine (NAC), a ROS scavenger, did not prevent the cytotoxicity induced by 13 nm AuNPs, indicating that 13 nm AuNPs (2 nM) induced ROS-independent apoptosis in chondrocytes. These results demonstrate the size-dependent cytotoxicity of AuNPs in chondrocytes, which must be seriously considered when using AuNPs for treatment of osteoarthritis (OA).

Dominant roles of Fenton reaction in sodium nitroprusside-induced chondrocyte apoptosis.

Sodium nitroprusside (SNP) has been widely used as an exogenous nitric oxide (NO) donor to explore the molecular mechanism of NO-mediated chondrocyte apoptosis during the latest two decades. We have recently found that NO-independent ROS play a key role in SNP-induced apoptosis in rabbit chondrocytes. This study aims to investigate what kind of ROS and how the reliable ROS mediators mediate the SNP-induced apoptosis. Data shows that SNP and NO-exhausted SNP (SNPex) induced ROS production or cytotoxicity to identically degree. SNP induced a marked increase in iron ions, superoxide anion (O2(•-)), hydrogen peroxide (H2O2) and hydroxyl radical ((•)OH) level. H2O2 scavenger (CAT) and (•)OH scavenger (DMSO) significantly inhibited SNP-induced chondrocyte apoptosis. Iron ions chelator (DFO) entirely prevented SNP-induced chondrocyte apoptosis. In contrast, O2(•-) scavenger (SOD) and glutathione depletion agent (BSO) promoted SNP-induced cytotoxicity. K3[Fe(CN)6] exhibited no cytotoxicity, and H2O2 alone up to 250µM or iron ions alone up to 90µM is non-cytotoxic to chondrocytes. Combination of 25µM FeSO4 and 100µM H2O2 in the presence of BSO induced chondrocyte death similar to SNP treatment. Fetal bovine serum (FBS) enhanced iron ions release from SNP and the cytotoxicity of SNP. Our data shows that the extracellular Fenton reaction between iron ions released from SNP and H2O2 induced by SNP plays a key role in SNP-induced chondrocyte apoptosis. Overall, our results indicate that the potential of SNP to increase iron ions and ROS should be especially considered for some biological functions and, possibly, also for clinical applications of this drug.

Resveratrol protects rabbit articular chondrocyte against sodium nitroprusside-induced apoptosis via scavenging ROS.

This study aims to investigate the mechanism by which resveratrol (RV) prevents sodium nitroprusside (SNP)-induced chondrocyte apoptosis, which is a characteristic feature of osteoarthritis (OA). Rabbit articular chondrocytes were pre-incubated with 100 µM RV for 18 h before 1.5 mM SNP co-treatment for 6 h. Cell viability was evaluated by CCK-8. Annexin V/PI double staining and Hoechst 33258 staining were used to determine the fashion of SNP-induced chondrocytes death. Mitochondrial membrane potential (ΔΨm) was measured by using flow cytometry (FCM) with TMRM and Rhodamine 123 staining. Intracellular reactive oxygen species (ROS) and nitric oxide (NO) levels were confirmed by FCM analysis with DCFH-DA and DAF-FM DA staining. Cytoskeleton proteins of chondrocytes co-stained with Actin-Trakcer Green and Tubulin-Trakcer Red were validated by confocal microscopy. SNP induced time- and dose-dependent chondrocytes apoptosis with decline of ΔΨm, activation of caspases as well as cytoskeletal remodeling. SNP induced a significant induction of both ROS and NO. RV remarkably prevented SNP-induced ROS production and apoptosis as well as cytoskeletal remodeling, but did not prevent SNP-induced NO production. Pretreatment with NO scavengers did not significantly prevent SNP-induced apoptosis and cytoskeletal remodeling. SNP induces NO-independent ROS production which dominates rabbit articular chondrocyte apoptosis, and RV protects chondrocytes against SNP-induced apoptosis via scavenging ROS instead of NO.

Artesunate induces apoptosis via a Bak-mediated caspase-independent intrinsic pathway in human lung adenocarcinoma cells.

This report is designed to explore the exact molecular mechanism by which artesunate (ART), a semisynthetic derivative of the herbal antimalaria drug artemisinin, induces apoptosis in human lung adenocarcinoma (ASTC-a-1 and A549) cell lines. ART treatment induced ROS-mediated apoptosis in a concentration- and time-dependent fashion accompanying the loss of mitochondrial potential and subsequent release of Smac and AIF indicative of intrinsic apoptosis pathway. Blockage of casapse-8 and -9 did not show any inhibitory effect on the ART-induced apoptosis, but which was remarkably prevented by silencing AIF. Of the utmost importance, ART treatment induced the activation of Bak but not Bax, and silencing Bak but not Bax remarkably inhibited ART-induced apoptosis and AIF release. Furthermore, although ART treatment did not induced a significant down-regulation of voltage-dependent anion channel 2 (VDAC2) expression and up-regulation of Bim expression, silencing VDAC2 potently enhanced the ART-induced Bak activation and apoptosis which were significantly prevented by silencing Bim. Collectively, our data firstly demonstrate that ART induces Bak-mediated caspase-independent intrinsic apoptosis in which Bim and VDAC2 as well as AIF play important roles in both ASTC-a-1 and A549 cell lines, indicating a potential therapeutic effect of ART for lung cancer.

Dihydroarteminsin-induced apoptosis is not dependent on the translocation of Bim to the endoplasmic reticulum in human lung adenocarcinoma cells.

Bim, a proapoptotic BH3-only member of Bcl-2 family, has been considered to play an important role in initiating mitochondrial apoptotic pathway. Our previous studies have shown the ability of dihydroarteminsin (DHA) to induce apoptosis in human lung adenocarcinoma (ASTC-a-1) cells. In this study, we investigated the function of Bim during DHA-induced apoptosis in ASTC-a-1 and another human lung adenocarcinoma (A549) cell lines. Confocal imaging of single living cell expressing GFP-BimL showed the translocation of Bim to endoplasmic reticulum (ER) rather than mitochondria during DHA-induced apoptosis. Moreover, we also found that DHA induced ER stress and an increase of Bim protein levels. However, silencing Bim by short hairpin RNA did not inhibit DHA-induced caspase-9 activation and cell apoptosis. Taken together, our results demonstrate for the first time that DHA induces Bim translocation to ER, but DHA-induced apoptosis is not dependent on Bim in ASTC-a-1 and A549 cell lines.

Artemisinin induces caspase-8/9-mediated and Bax/Bak-independent apoptosis in human lung adenocarcinoma (ASTC-a-1) cells.

Artemisinin (ARTE), an antimalarial phytochemical component from the sweet wormwood plant, has been shown a potential anticancer activity by inducing cell apoptosis. The aim of this report is to explore the mechanism of ARTE-induced human lung adenocarcinoma (ASTC-a-1) cell apoptosis. Cell counting kit (CCK-8) assay showed that ARTE induced cytotoxcity in a dose- and time-dependent manner. Confocal microscopy fluorescence imaging of cells stained with Hoechst 33258 and flow cytometry (FCM) analysis of cells stained with Annexin V-FITC/propidium iodide (PI) showed that ARTE induced reactive oxygen species (ROS)-dependent apoptosis. Confocal fluorescence resonance energy transfer (FRET) imaging of single living cells expressing SCAT3, SCAT9 or CFP-Bid-YFP and fluorometic substrate assay showed that ARTE induced the activation of caspase-3, -8 and -9. Moreover, inhibition of caspase-8 or -9 completely blocked ARTE-induced apoptosis which was only partially attenuated by caspase-3 inhibitor. Interestingly, silencing Bax and Bak by RNA interference (RNAi) did not attenuate ARTE-induced apoptosis. Collectively, ARTE induces caspase-dependent but Bax/Bak-independent apoptosis in ASTC-a-1 cells.

The mitotic kinase Aurora-A induces mammary cell migration and breast cancer metastasis by activating the Cofilin-F-actin pathway.

The mitotic kinase Aurora-A (Aur-A) is required to form the bipolar spindle and ensure accurate chromosome segregation before cell division. Aur-A dysregulation represents an oncogenic event that promotes tumor formation. Here, we report that Aur-A promotes breast cancer metastasis. Aur-A overexpression enhanced mammary cell migration by dephosphorylation and activation of cofilin, which facilitates actin reorganization and polymerization. Cofilin knockdown impaired Aur-A-driven cell migration and protrusion of the cell membrane. Conversely, overexpression of activated cofilin abrogated the effects of Aur-A knockdown on cell migration. Moreover, Aur-A overexpession increased the expression of the cofilin phosphatase Slingshot-1 (SSH1), contributing to cofilin activation and cell migration. We found that phosphatidylinositol 3-kinase (PI3K) inhibition blocked Aur-A-induced cofilin dephosphorylation, actin reorganization, and cell migration, suggesting crosstalk with PI3K signaling and a potential benefit of PI3K inhibition in tumors with deregulated Aur-A. Additionally, we found an association between Aur-A overexpression and cofilin activity in breast cancer tissues. Our findings indicate that activation of the cofilin-F-actin pathway contributes to tumor cell migration and metastasis enhanced by Aur-A, revealing a novel function for mitotic Aur-A kinase in tumor progression.

Single-cell analysis of dihydroartemisinin-induced apoptosis through reactive oxygen species-mediated caspase-8 activation and mitochondrial pathway in ASTC-a-1 cells using fluorescence imaging techniques.

Dihydroartemisinin (DHA), a front-line antimalarial herbal compound, has been shown to possess promising anticancer activity with low toxicity. We have previously reported that DHA induced caspase-3-dependent apoptosis in human lung adenocarcinoma cells. However, the cellular target and molecular mechanism of DHA-induced apoptosis is still poorly defined. We use confocal fluorescence microscopy imaging, fluorescence resonance energy transfer, and fluorescence recovery after photobleaching techniques to explore the roles of DHA-elicited reactive oxygen species (ROS) in the DHA-induced Bcl-2 family proteins activation, mitochondrial dysfunction, caspase cascade, and cell death. Cell Counting Kit-8 assay and flow cytometry analysis showed that DHA induced ROS-mediated apoptosis. Confocal imaging analysis in a single living cell and Western blot assay showed that DHA triggered ROS-dependent Bax translocation, mitochondrial membrane depolarization, alteration of mitochondrial morphology, cytochrome c release, caspase-9, caspase-8, and caspase-3 activation, indicating the coexistence of ROS-mediated mitochondrial and death receptor pathway. Collectively, our findings demonstrate for the first time that DHA induces cell apoptosis by triggering ROS-mediated caspase-8/Bid activation and the mitochondrial pathway, which provides some novel insights into the application of DHA as a potential anticancer drug and a new therapeutic strategy by targeting ROS signaling in lung adenocarcinoma therapy in the future.

The JNK inhibitor SP600125 enhances dihydroartemisinin-induced apoptosis by accelerating Bax translocation into mitochondria in human lung adenocarcinoma cells.

The C-Jun N-terminal Kinase (JNK) inhibitor SP600125 is widely used to inhibit the JNK-mediated Bax activation and cell apoptosis. However, this report demonstrates that SP600125 synergistically enhances the dihydroartemisinin (DHA)-induced human lung adenocarcinoma cell apoptosis by accelerating Bax translocation and subsequent intrinsic apoptotic pathway involving mitochondrial membrane depolarization, cytochrome c release, caspase-9 and caspase-3 activation. The dynamical analysis of GFP-Bax mobility inside single living cells using fluorescence recovery after photobleaching revealed that SP600125 aggravated the DHA-induced decrease of Bax mobility and Bax translocation. These results for the first time present a novel pro-apoptotic action of SP600125 in DHA-induced apoptosis.

Taxol induces concentration-dependent apoptotic and paraptosis-like cell death in human lung adenocarcinoma (ASTC-a-1) cells.

Taxol (Paclitaxel) is an important natural product for the treatment of solid tumors such as ovarian, breast, non-small-cell lung tumors, and some head and neck carcinomas. Different concentrations of taxol trigger distinct effects on cell death forms. In present study, cell counting kit (CCK-8) assay, confocal fluorescence microscopy imaging, flow cytometry (FCM) and western blotting (WB) analysis were used to analyze the characteristics of cell death induced by low (35 nM) and high (70 microM) concentration of taxol respectively in human lung adenocarcinoma (ASTC-a-1) cells. Our results showed that low concentration of taxol induced cell death dominantly in apoptotic fashion associated with nuclear fragmentation, protein synthesis, phosphatidylserine (PS) externalization, G2/M cell cycle arrest, Bax translocation into mitochondria and caspase-3 activation, whereas high concentration of this drug induced significant cytoplasm vacuolization, mitochondria swelling and paraptosis-like cell death form without protein synthesis that is necessary for paraptosis. Although the mechanism of high concentration of taxol-induced paraptosis-like cell death has not been clear, this finding might have a potential implication for cancer therapy, especially for apoptosis-resistant cancer.

[Nucleoplasmic viscosity of living cells investigated by fluorescence correlation spectroscopy].

In order to non-invasively investigate nucleoplasmic viscosity in real time with good temporal resolution, the present study firstly introduced a new method based on fluorescence correlation spectroscopy (FCS). FCS is a kind of single-molecule technique with high temporal and spatial resolution to analyze the dynamics of fluorescent molecules in nanomolar concentration. Through a time correlation analysis of spontaneous intensity fluctuations, this technique in conjunction with EGFP as a probe is capable of determining nucleoplasmic viscosity in terms of Stokes-Einstein equation as well as its corresponding analysis of the diffusion coefficient for EGFP in the nucleus. The results showed that nucleoplasmic viscosity of ASTC-a-1 cells and HeLa cells were respectively (2.55 +/- 0.61) cP and (2.04 +/- 0.49) cP at pH 7.4 and 37 degrees C, consistent with the results by traditional methods, and nucleoplasmic viscosity was found to be larger than cytoplasmic viscosity. Meanwhile, the real-time analysis of nucleoplasmic viscosity in living cells exposed to hypotonic media proved that FCS could be used to track the changing rheological characteristics of the nucleoplasm in living cells. Taken together, this study suggests that FCS provides an accurate and non-invasive method to investigate the microenvironment in living cells on the femtoliter scale and it can be used as a powerful tool in researches on the dynamical processes of intracellular molecules.

Dihydroartemisinin (DHA) induces caspase-3-dependent apoptosis in human lung adenocarcinoma ASTC-a-1 cells.

BACKGROUND: Dihydroartemisinin (DHA), a semi-synthetic derivative of artemisinin, isolated from the traditional Chinese herb Artemisia annua, is recommended as the first-line anti-malarial drug with low toxicity. DHA has been shown to possess promising anticancer activities and induce cancer cell death through apoptotic pathways, although the molecular mechanisms are not well understood. METHODS: In this study, cell counting kit (CCK-8) assay was employed to evaluate the survival of DHA-treated ASTC-a-1 cells. The induction of apoptosis was detected by Hoechst 33258 and PI staining as well as flow cytometry analysis. Collapse of mitochondrial transmembrane potential (DeltaPsim) was measured by dynamic detection under a laser scanning confocal microscope and flow cytometry analysis using Rhodamine123. Caspase-3 activities measured with or without Z-VAD-fmk (a broad spectrum caspase inhibitor) pretreatment by FRET techniques, caspase-3 activity measurement, and western blotting analysis. RESULTS: Our results indicated that DHA induced apoptotic cell death in a dose- and time-dependent manner, which was accompanied by mitochondrial morphology changes, the loss of DeltaPsim and the activation of caspase-3. CONCLUSION: These results show for the first time that DHA can inhibit proliferation and induce apoptosis via caspase-3-dependent mitochondrial death pathway in ASTC-a-1 cells. Our work may provide evidence for further studies of DHA as a possible anticancer drug in the clinical treatment of lung adenocarcinoma.

[Fluorescence emission analysis of caspase-3 activation induced by Xiao-Ai-Ping (XAP) inside living human lung adenocarcinoma cells].

The CCK-8 was used to measure the inhibition effect of Xiao-Ai-Ping (XAP), a traditional medicine, on the human lung adenocarcinoma (ASTC-a-1) cells viability. The ASTC-a-1 cells expressing stably with SCAT3, a fluorescence resonance energy transfer (FRET) plasmid based on the green fluorescent protein mutants (GFPs), was verified using confocal fluorescence scanning microscopy imaging, fluorescence emission spectra and FRET acceptor photobleaching techniques. The caspase-3 activation can be monitored by the fluorescence emission spectra of SCAT3 inside living cells. The cells expressing stably with SCAT3 were cultured with XAP for 96 hours, and the fluorescence emission spectra of the SCAT3 inside living cells were measured at the time of 0, 24, 72, and 96 hours, respectively. Experimental results showed that: (1)XAP inhibited obviously the proliferation of ASTC-a-1 cells and induced the cell death. The inhibition of XAP on the cells was dose-dependent; (2)the SCAT3 inside living cells was cleaved completely 72 hours after the XAP treatment, implying that a great deal of pro-caspase-3 was activated by XAP; (3)24 hours after XAP treatment, the emission spectra of SCAT3 inside living cells cultured in DMEM without XAP for 48 and 72 hours did not change greatly, implying that XAP did not activate obviously caspase-3 within 24 hours.

Taxol induces caspase-independent cytoplasmic vacuolization and cell death through endoplasmic reticulum (ER) swelling in ASTC-a-1 cells.

High concentration of taxol was found to induce programmed cell death (PCD) and cytoplasm vacuolization in human lung adenocarcinoma (ASTC-a-1) cells. To elucidate the relationship between the PCD and cytoplasm vacuolization, confocal fluorescence microscopy was performed on the cytoplasm vacuolization, endoplasmic reticulum (ER) and mitochondria swelling after taxol treatment in living cells. erRFP plasmid was used to probe the ER distribution, and SCAT3 plasmid was used to monitor the caspase-3 activation in living cells. Our results showed that taxol induced concentration-dependent and caspases-independent cytoplasm vacuolization and cell death through ER and mitochondria swelling. Live confocal imaging of ASTC-a-1 cells stably expressing SCAT3 further verified that taxol-induced cytoplasm vacuolization and cell death was caspase-3-independent. In conclusion, we found for the first time that taxol induces a paraptosis-like PCD in the ASTC-a-1 cells by cytoplasm vacuolization due to the swelling of both ER and mitochondria without activating the caspase enzymes.

Live morphological analysis of taxol-induced cytoplasmic vacuolization [corrected] in human lung adenocarcinoma cells.

Taxol (paclitaxel), one of the most active cancer chemotherapeutic agents, can cause programmed cell death (PCD) and cytoplasmic vacuolization. The objective of this study was to analyze the morphological characteristics induced by taxol. Human lung adenocarcinoma (ASTC-a-1) cells were exposed to various concentration of taxol. CCK-8 was used to assay the cell viability. Atomic force microscopy (AFM), plasmid transfection and confocal fluorescence microscopy were performed to image the cells morphological change induced by taxol. Fluorescence resonance energy transfer (FRET) was used to monitor the caspase-3 activation in living cells during taxol-induced cell death. Cells treated with taxol exhibited significant swelling and cytoplasmic vacuolization which may be due to endoplasmic reticulum (ER) vacuolization. Caspase-3 was not activated during taxol-induced cytoplasmic vacuolization and cell death. These findings suggest that taxol induces caspase-3-independent cytoplasmic vacuolization, cell swelling and cell death through ER vacuolization.

[Fluorescence analysis of taxol-induced paraptosis-like independent of caspase-3 activation].

In the present report, the authors for the first time described the characteristics of taxol-induced paraptosis-like for the human lung adenocarcinoma cells (ASTC-a-1). CCK-8 was used to assay the inhibition of taxol on the cells viability. Cell viability was inhibited obviously 24 h after taxol treatment. Confocal fluorescence scanning microscope was used to monitor the morphology changes in cells with taxol treatment. Fluorescence resonance energy transfer (FRET) and acceptor photobleaching techniques were used to analyze the caspase-3 activation in the taxol-induced cell swelling and cell dearth. Taxol induced cell swelling, cytoplasmatic vacuolization and cell death without cell shrinkage, an apoptotic feature, and membrane rupture, a necrotic feature. The emission spectra of scat3 inside living cells expressed stably with scat3 were the same for control (without taxol). Further analysis with FRET and acceptor photobleaching techniques showed that the caspase-3 was not activated by taxol for the cytoplastic vacuoliazation cells expressed stably with scat3 plasmid, suggesting that caspase-3 is not involved in the taxol-inducecd cell swelling, cytoplasmatic vacuolization and cell death. These results show that taxol can induce a novel nonapoptotic PCD resembling the paraptosis in ASTC-a-1 cells.

[Microbial community composition and phylogenetic analysis of deodor biofilter under different pH conditions].

Molecular biological methods were applied to analyze the genetic diversity of microbe community in biofilter. V3 variable fragments of genes coding for 16S rRNA were amplified by Polymerase Chain Reaction. Then PCR-DGGE combined technique were used to analyze the microbial population composition and phylogeny of deodorant biofilter. The results indicate that there are prominent differences in microbial diversity and abundance between acid and neutral conditions. Owing to the selective pressure of extreme acidity, there is less diversity of microbe compared with that in neutral environment. It is demonstrated the obvious distinction of spacial diversity in different biofilter bed as well. PCR and T-vector cloning sequencing results shows that the sulfur-oxidizing bacteria are the predominant population. The research offers the valid scientific basis for better treatment of odorant gas and the theoretical foundation for application of bio-deodorization.