CXCL2/CXCR2 axis induces cancer stem cell characteristics in CPT-11-resistant LoVo colon cancer cells via Gαi-2 and Gαq/11.

Cancer stem cells (CSCs) exist in colon cancer and exhibit characteristics of stem cells which are due to lineages of tissues where they arise. Epithelial to mesenchymal transition (EMT)-undergoing cancer cells display CSC properties and therapeutic resistance. Cancer and stromal cells comprise of a tumor microenvironment. One way the two populations communicate with each other is to secret CXC ligands (CXCLs). CXCLs are capable of causing chemotaxis of specific types of stromal cells and control angiogenesis. Double immunofluorescence, western blot analysis, and colony-formation assay were carried out to compare parental and CPT-11-resistant LoVo cells. CPT-11-R LoVo colon cancer cells showed increased expression of CXCL1, CXCL2, CXCL3, and CXCL8. They displayed significantly increased intracellular protein levels of CXCL2 and CXCR2. CPT-11-R LoVo cells showed significantly elevated expression in aldehyde dehydrogenase 1 (ALDH1), cluster of differentiation 24 (CD24), cluster of differentiation 44 (CD44), and epithelial cell adhesion molecule (EpCAM). CXCL2 knockdown by short hairpin RNA resulted in reduced expression of CSC proteins, cyclins, EMT markers, G proteins, and matrix metalloproteinases (MMPs). Finally, Gαi-2 was found to promote expression of CSC genes and tumorigenesis which were more apparent in the resistant cells. In addition, Gαq/11 showed a similar pattern with exceptions of EpCAM and MMP9. Therefore, CXCL2-CXCR2 axis mediates through Gαi-2 and Gαq/11 to promote tumorigenesis and contributes to CSC properties of CPT-11-R LoVo cells.

Fisetin mediated apoptotic cell death in parental and Oxaliplatin/irinotecan resistant colorectal cancer cells in vitro and in vivo.

Irinotecan (CPT11) and Oxaliplatin have been used in combination with fluorouracil and leucovorin for treating colorectal cancer. However, the efficacy of these drugs is reduced due to various side effects and drug resistance. Fisetin, a hydroxyflavone possess anti-proliferative, anti-cancer, anti-inflammatory, and antioxidant activity against various types of cancers. Apart from that, fisetin has been shown to induce cytotoxic effects when combined with other known chemotherapeutic drugs. In this study, we aimed to investigate whether Fisetin was capable of sensitizing both Irinotecan and Oxaliplatin resistance colon cancer cells and explored the possible signaling pathways involved using In vitro and In vivo models. The results showed that Fisetin treatment effectively inhibited cell viability and apoptosis of CPT11-LoVo cells than Oxaliplatin (OR) and parental LoVo cancer cells. Western blot assays suggested that apoptosis was induced by fisetin administration, promoting Caspase-8, and Cytochrome-C expressions possibly by inhibiting aberrant activation of IGF1R and AKT proteins. Furthermore, fisetin inhibited tumor growth in athymic nude mouse xenograft model. Overall, our results provided a basis for Fisetin as a promising agent to treat parental as well as chemoresistance colon cancer.

Oxaliplatin resistance in colorectal cancer cells is mediated via activation of ABCG2 to alleviate ER stress induced apoptosis.

Oxaliplatin (OXA), is a third generation platinum drug used as first-line chemotherapy in colorectal cancer (CRC). Cancer cells acquires resistance to anti-cancer drug and develops resistance. ATP-binding cassette (ABC) drug transporter ABCG2, one of multidrug resistance (MDR) protein which can effectively discharge a wide spectrum of chemotherapeutic agents out of cancer cells and subsequently reduce the intracellular concentration of these drugs. Role of ABCG2 and plausible molecular signaling pathways involved in Oxaliplatin-Resistant (OXA-R) colon cancer cells was evaluated in the present study. OXA resistant LoVo cells was developed by exposing the colon cells to OXA in a dose-dependent manner. Development of multi drug resistance in OXA-R cells was confirmed by exposing the resistance cells to oxaliplatin, 5-FU, and doxorubicin. OXA treatment resulted in G2 phase arrest in parental LoVo cells, which was overcome by OXA-R LoVo cells. mRNA and protein expression of ABCG2 and phosphorylation of NF-κB was significantly higher in OXA-R than parental cells. Levels of ER stress markers were downregulated in OXA-R than parental cells. OXA-R LoVo cells exposed to NF-κB inhibitor QNZ effectively reduced the ABCG2 and p-NF-κB expression and increased ER stress marker expression. On other hand, invasion and migratory effect of OXA-R cells were found to be decreased, when compared to parental cells. Metastasis marker proteins also downregulated in OXA-R cells. ABCG2 inhibitor verapamil, downregulate ABCG2, induce ER stress markers and induces apoptosis. In vivo studies in nude mice also confirms the same.

Overexpression of ZAKß in human osteosarcoma cells enhances ZAKα expression, resulting in a synergistic apoptotic effect.

ZAK is a novel mixed lineage kinase-like protein that contains a leucine-zipper and a sterile-alpha motif as a protein-protein interaction domain, and it is located in the cytoplasm. There are 2 alternatively spliced forms of ZAK: ZAKα and ZAKß. Previous studies showed that ZAKα is involved in various cell processes, including cell proliferation, cell differentiation, and cardiac hypertrophy, but the molecular mechanism of ZAKß is not yet known. In a recent study in our laboratory, we found that ZAKß can ameliorate the apoptotic effect induced by ZAKα in H9c2 cells. We further hypothesized that ZAKß could also improve the apoptotic effect induced by ZAKα in human osteosarcoma cells. The results of this study show that ZAKß can induce apoptosis and decrease cell viability similar to the effects of ZAKα. Interestingly, our ZAKα-specific inhibitor assay shows that the expression of ZAKß is highly dependent on ZAKα expression. However, ZAKß expression effectively induces ZAKα expression and results in synergistic enhancement of apoptosis in human osteosarcoma cells. Furthermore, co-immunoprecipitation results revealed that ZAKα can directly interact with ZAKß, and this interaction may contribute to the enhanced apoptotic effects. SIGNIFICANCE OF THE STUDY: ZAK is a mixed lineage kinase involved in cell differentiation, proliferation, and hypertrophic growth. ZAKα isoform of ZAK is associated with tumorigenesis, but the function of ZAKß is not yet known. In H9c2 cells, ZAKß was found to ameliorate the apoptotic effect induced by ZAKα. However, in osteosarcoma cells, ZAKß elevates the apoptotic effect induced by ZAKα. In this study, we show that similar to ZAKα, the ZAKß induces apoptosis and decreases cell viability. Interestingly, the expression of ZAKß is dependent on ZAKα expression, and ZAKß further enhances ZAKα expression and results in synergistic enhancement of apoptosis in osteosarcoma cells.

Doxorubicin induces ZAKα overexpression with a subsequent enhancement of apoptosis and attenuation of survivability in human osteosarcoma cells.

Human osteosarcoma (OS) is a malignant cancer of the bone. It exhibits a characteristic malignant osteoblastic transformation and produces a diseased osteoid. A previous study demonstrated that doxorubicin (DOX) chemotherapy decreases human OS cell proliferation and might enhance the relative RNA expression of ZAK. However, the impact of ZAKα overexpression on the OS cell proliferation that is inhibited by DOX and the molecular mechanism underlying this effect are not yet known. ZAK is a protein kinase of the MAPKKK family and functions to promote apoptosis. In our study, we found that ZAKα overexpression induced an apoptotic effect in human OS cells. Treatment of human OS cells with DOX enhanced ZAKα expression and decreased cancer cell viability while increasing apoptosis of human OS cells. In the meantime, suppression of ZAKα expression using shRNA and inhibitor D1771 both suppressed the DOX therapeutic effect. These findings reveal a novel molecular mechanism underlying the DOX effect on human OS cells. Taken together, our findings demonstrate that ZAKα enhances the apoptotic effect and decreases cell viability in DOX-treated human OS cells.

Importance of PLC-Dependent PI3K/AKT and AMPK Signaling in RANTES/CCR5 Mediated Macrophage Chemotaxis.

Regulated upon activation, normal T cell expressed, and secreted (RANTES), also known as chemokine ligand 5 (CCL5), has been reported to facilitate macrophage migration, which plays a crucial role in tissue inflammation. The aim of this study is to investigate the characteristics and underlying mechanism of RANTES on macrophage chemotaxis under physiological and pathological conditions. The study was conducted on macrophage RAW264.7 cell and bone marrow-derived macrophages (BMDM) isolated from CCL receptor 5 (CCR5) knockout mice. The macrophage migration and glucose uptake was assessed in time and dose dependent manners. Moreover, reverse transcription-polymerase chain reaction (RT-PCR) and western blot analysis were used to characterize mRNA and protein level related to the underlying mechanism. The present result showed that the maraviroc, a selective CCR5 inhibitor, dose-dependently suppressed RANTES-induced rapid increases in glucose uptake and cell migration in RAW264.7 cells. Similar effects were observed in the BMDM isolated from CCR5 knockout mice compared with wild type control. RANTES treatment promptly enhanced membrane glucose transporter 1 (GLUT1) expression, glucose uptake as well as phosphorylation of AKT on Thr308, Ser473 within min and has prolonged effect on phosphorylation of AMP-activated protein kinase (AMPK) on Thr172, which were abrogated by maraviroc, CCR5 siRNA or phospholipase C (PLC) inhibitor in RAW264.7 cells. Inhibition of PI3K and AMPK by LY294002 and Compound C significantly suppress RANTES-stimulated macrophage glucose uptake and migration, respectively. RANTES has biphasic effect on activating PLC signaling including prompt action on PI3K/AKT phosphorylation and prolong action on AMPK phosphorylation via CCR5 which leads to increased GLUT1-mediated glucose uptake and macrophage migration under physiopathological states.

Taiwanin C selectively inhibits arecoline and 4-NQO-induced oral cancer cell proliferation via ERK1/2 inactivation.

Arecoline, the most abundant alkaloid in betel nut is known to promote abnormal proliferation of epithelial cells by enhancing epidermal growth factor receptor (EGFR) activation and cyclooxygenase-2 (COX2) expression. Taiwanin C, a naturally occurring lignan extracted from Taiwania cryptomerioides, has been found to be a potential inhibitor of COX2 expression. Based on the MTT assay results, taiwanin C was found to be effective in inhibiting the tumorous T28 cell than the non-tumorous N28 cells. The modulations in the expression of relevant proteins were determined to understand the mechanism induced by taiwanin C to inhibit T28 cell proliferation. The levels of activated EGFR and COX2 were found to be abnormally high in the T28 oral cancer cells. However, taiwanin C was found to inhibit the activation of EGFR and regulated other related downstream proteins and thereby inhibited the T28 cell proliferation. In conclusion the results indicate that taiwanin C suppresses COX2-EGFR and enhances P27 pathways to suppress arecoline induced oral cancer cell proliferation via ERK1/2 inactivation. © 2015 Wiley Periodicals, Inc. Environ Toxicol 32: 62-69, 2017.

Estrogen and ERα enhanced ß-catenin degradation and suppressed its downstream target genes to block the metastatic function of HA22T hepatocellular carcinoma cells via modulating GSK-3ß and ß-TrCP expression.

In our previous experiments, we found ß-catenin was highly expressed in the tumor area with high invasive ability and poor prognosis. In this study, we have examined the mechanism by which ERα regulates ß-catenin expression as well as the metastasis ability of hepatocellular cancer HA22T cells. To identify whether the anticancer effect of estrogen and ERα is mediated through suppression of ß-catenin expression, we co-transfected pCMV-ß-catenin and ERα into HA22T cells, and determined the cell motility by wound healing, invasion, and migration assays. Results showed that estrogen and/or ERα inhibited ß-catenin gene expression and repressed HA22T cell motility demonstrated that similar data was observed in cells expressing the ERα stable clone. Moreover, we examined the protein-protein interaction between ERα and ß-catenin by immunostain, co-immunoprecipitation, and Western blotting. E2 enhanced the binding of ERα with ß-catenin and then triggered ß-catenin to bind with E3 ligase (ßTrCP) to promote ß-catenin degradation. Finally by employing systematic ChIP studies, we showed ERα can interact directly with the ß-catenin promoter region following E2 treatment. All our results reveal that estrogen and ERα blocked metastatic function of HA22T cells by modulating GSK3ß and ßTrCP expression and further enhanced ß-catenin degradation and suppressed its downstream target genes. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 519-529, 2017.

Inhibition of NF-κB and metastasis in irinotecan (CPT-11)-resistant LoVo colon cancer cells by thymoquinone via JNK and p38.

Clinically used chemotherapeutics can effectively eliminate most tumor cells. However, they cause unwanted side effects and result in chemoresistance. To overcome such problems, phytochemicals are now used to treat cancers by means of targeted therapy. Thymoquinone (TQ) is used to treat different cancers (including colon cancer) and is an NF-κB inhibitor. Irinotecan resistant (CPT-11-R) LoVo colon cancer cell line was previous constructed by step-wise CPT-11 challenges to un-treated parental LoVo cells and expresses EGFR/IKKα/ß/NF-κB pathway. TQ resulted in reduced total and phosphorylation of IKKα/ß and NF-κB and decreased metastasis in CPT-11-R cells. TQ not only reduced activity of ERK1/2 and PI3K but also activated JNK and p38. Furthermore, TQ was also found to suppress metastasis through activation of JNK and p38. Therefore, TQ suppressed metastasis through NF-κB inhibition and activation of JNK and p38 in CPT-11-R LoVo colon cancer cells. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 669-678, 2017.

Helioxanthin suppresses the cross talk of COX-2/PGE2 and EGFR/ERK pathway to inhibit Arecoline-induced Oral Cancer Cell (T28) proliferation and blocks tumor growth in xenografted nude mice.

Helioxanthin, an active compound from Taiwania cryptomerioides Hayata, has been shown to have various biological activities. However, their anticancer effect in oral squamous cell carcinoma has not been well established yet. Helioxanthin inhibited the proliferation of oral squamous cell carcinoma cells in a dose-dependent manner by inducing G2/M phase arrest. Similarly, helioxanthin inhibited cyclooxygenase-2, (COX-2), phosphorylated EGFR, and extracellular-signal-regulated kinases (ERK) protein level and further reduced the nuclear accumulation of phosphorylated epidermal growth factor receptor (pEGFR) and activator protein-1(AP-1) family protein, c-fos. Moreover, helioxanthin at the dose of 20 and 30 mg kg-1 for 15 days reduced the tumor growth in animal model. This study demonstrated that Helioxanthin exerts its anticancer activity against oral cancer cells by downregulating EGFR/ERK/c-fos signaling pathway to inhibit COX-2 level and by activating cyclin-dependent kinase inhibitor (p27) to further induce G2/M cell cycle arrest. This helioxanthin may serve as a novel candidate for oral cancer prevention. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 2045-2056, 2016.

Circulating anti-cyclic citrullinated peptide antibody in patients with rheumatoid arthritis and chronic obstructive pulmonary disease.

Anti-cyclic citrullinated peptide (anti-CCP) antibody is highly specific for diagnosing rheumatoid arthritis (RA). Cigarette smoking is a lifestyle and environmental factor associated with anti-CCP production and is strongly associated with chronic obstructive pulmonary disease (COPD). This study assessed levels of anti-CCP antibodies and rheumatoid factor (RF) among patients with RA and COPD. The study sample comprised 63 patients with RA and 70 patients with COPD, all of whom underwent assessment of anti-CCP antibody and RF levels. Testing revealed that 54.2% of RA patients and 0% of COPD patients were positive for anti-CCP antibodies. Additionally, 82.5% of RA patients and 42% of COPD patients were positive for RF. Among RA patients, levels of anti-CCP antibodies were higher among smokers than among nonsmokers (242.7 ± 128.3 vs. 68.1 ± 112.1, P < 0.001). COPD patients had low titers of RF but were negative for anti-CCP antibodies. The presence of anti-CCP antibodies was a reliable serologic marker in RA diagnosis and was associated with cigarette smoking.

Apicidin-resistant HA22T hepatocellular carcinoma cells strongly activated the Wnt/ß-catenin signaling pathway and MMP-2 expression via the IGF-IR/PI3K/Akt signaling pathway enhancing cell metastatic effect.

The IGF-IR/PI3K/Akt signaling pathway inhibited GSK3-ß activity by phosphorylation and this promoted ß-catenin nuclear localization. Our previous study indicated that ß-catenin mRNA level was significantly higher in tumor areas than in non-tumor ones, especially in late pathologic stage tumors. However, ß-catenin inhibition resulted in significantly suppressed migration and invasion ability of HA22T cells. Thus, Wnt/ß-catenin pathway over-activation might be involved in metastatic enhancement of apicidin-resistant HA22T cell metastasis. Apicidin-resistant (AR) HA22T cells showed higher ß-catenin nuclear accumulation and significantly decreased GSK-3-ß protein level, in relation to parental cells. Results also indicated that AR cells increased abundantly in Tbx3, a downstream target of Wnt/ß-catenin that it is implicated in liver cancer. AR cells also inhibited the MEK/ERK/PEA3 pathway which promoted MMP-2 activation. But, apicidin-resistant effect was totally reversed by LY294002 and AG1024. In conclusion, Apicidin-R HA22T cells activated the Wnt/ß-catenin pathway and induced, MMP-2 expression via IGF-IR/PI3K/Akt signaling further enhancing cell the metastatic effects.

Activation of snail and EMT-like signaling via the IKKαß/NF-κB pathway in Apicidin-resistant HA22T hepatocellular carcinoma cells.

The molecular and phenotypic associations between chemo- or radio-resistance and the acquisition of epithelial-mesenchymal transition (EMT)-like phenotype are tightly related in cancer cells. Wnt/ß- catenin and NF-κB signaling pathways play crucial roles in EMT induction. Apicidin-resistant (Apicidin- R) HA22T cells are known to activate the Wnt/ß-catenin signaling pathway and MMP-2 expression via the IGF-IR/PI3K/Akt signaling pathway to enhance metastatic effects of cancer cells. In this study, we further investigated if Apicidin-R HA22T cells actually underwent EMT. In Apicidin-R HA22T cells, E-cadherin protein level was reduced but Vimentin, Snail and Twist were significantly activated. Activation of p-IKKαß and p-IκBα was also observed in Apicidin-R HA22T cells. Apicidin-R HA22T cells displayed even higher NF-κB nuclear accumulation. Snail was enhanced but GSK3-ß was reduced. However, unphosphorylated GSK3-ß protein level was totally reversed when the Snail-specific siRNA was applied in a knockdown experiment. Taken together, Apicidin-R HA22T cells could potentiate aggressive metastasis behavior due to up-regulation of Snail expression and promoted EMT effects via the IKKαß/NF-κB pathway. In addition, Snail might decrease the GSK3-ß level resulting in extraordinarily activation of Wnt/ß-catenin signaling pathway.

Increasing Use of Telemedicine for Neurological Disorders During the COVID-19 Pandemic: A Mini-Review.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a highly contagious viral infection. In addition to its association with common pulmonary and gastrointestinal complications, COVID-19 is also associated with numerous neurological and neuropsychiatric conditions. This minireview aims to cover current literature addressing the application of telemedicine in neurological disorders and neuropsychiatric conditions, especially in response to the COVID-19 pandemic. This article revealed that quarantine, masking, and social distancing policies practiced during the COVID-19 pandemic involved restrictions and challenges to providing medical services, especially for patients with neurological disorders with or without COVID-19 infection. During the pandemic, both healthcare administrators and clinicians, including neurologists, have rapidly adapted or introduced telemedicine technologies for delivering specialty care. In some areas in the world, telemedicine has been successfully applied to reduce the impact imposed by COVID-19. Conclusively, this article supports the idea that telemedicine is an effective tool for providing specialized healthcare for patients with neurological conditions while adhering to social distancing or lockdown policies instituted during the COVID-19 pandemic. Government and medical/healthcare authorities, physicians and healthcare providers need to work together to expand the adoption of telemedicine applications, even after the COVID-19 crisis.

ZAK inhibits human lung cancer cell growth via ERK and JNK activation in an AP-1-dependent manner.

Novel mixed-lineage kinase protein zipper sterile-alpha-motif kinase (ZAK) was first cloned by our laboratory. Lung cancer is the leading cause of cancer-related death in the world, including in Taiwan. Here, we wanted to investigate whether ZAK plays a potential role in lung cancer development. First, Western blot analysis results demonstrated that four cell lines expressed high levels of ZAK from among a panel of 10 lung cancer cell lines, and two of three normal lung cells expressed ZAK. ZAK gene expressions were down-regulated in lung cancers by real-time PCR analysis. Overexpression of ZAK suppressed cell proliferation in parallel with increased phosphorylated levels of extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK). In contrast, ZAK silencing cells inhibited the expressions of phosphorylated ERK and JNK without affecting the expression of phosphorylated p38. The effect of the decreased cell growth rate was significantly but incompletely reversed when ZAK-overexpressing cells were treated with a specific ERK or JNK inhibitor. Moreover, c-Fos and c-Jun, the major downstream components of MAPKs, were up-regulated by ERK and JNK, respectively. When ZAK-overexpressing cells introduced with c-Jun RNA interference (RNAi), the activator protein-1 (AP-1) transcription activity detected by a secreted alkaline phosphatase (SEAP) assay was suppressed and the decreased cell number was reversed compared with the control RNAi-treated group. More importantly, ZAK significantly depressed tumor growth in in vivo study. Taken together, results from both in vitro and in vivo studies indicated that the decrease of lung cancer cell proliferation by ZAK may involve the ERK and JNK pathways via an AP-1 transcription factor.

Correction: Liu, Y.-S.; et al. Inhibition of Protein Phosphatase 1 Stimulates Noncanonical ER Stress eIF2α Activation to Enhance Fisetin-Induced Chemosensitivity in HDAC Inhibitor-Resistant Hepatocellular Carcinoma Cells. Cancers 2019, 11, 918.

It has been reported that two sets of blot figures in Figure 3A,C looked identical in the original published paper [...].

Chemoresistance-Associated Silencing of miR-4454 Promotes Colorectal Cancer Aggression through the GNL3L and NF-κB Pathway.

Guanine nucleotide-binding protein-like-3-like (GNL3L) is a crucial regulator of NF-κB signaling that is aberrantly activated during diverse chemoresistance-associated cellular processes. However, the molecular mechanisms of GNL3L tumor initiation and resistant state are largely unknown. Moreover, the identification of predictive biomarkers is necessary to effectively generate therapeutic strategies for metastatic human colorectal cancer (CRC). This study aims to identify how cells acquire resistance to anticancer drugs and whether the downregulation of miR-4454 is associated with the progression of CRC. Here, we have shown that the overexpression of miR-4454 in resistant tumors is a crucial precursor for the posttranscriptional repression of GNL3L in human chemoresistant CRC progression, and we used doxycycline induced miR-4454 overexpression that significantly reduced tumor volume in a subcutaneous injection nude mice model. Together, these observations highlight that the downregulation of miR-4454 in resistant clones is prominently responsible for maintaining their resistance against anticancer drug therapy. Our study indicates that the development of miR-4454 as a microRNA-based therapeutic approach to silence GNL3L may remarkably reduce oncogenic cell survival that depends on GNL3L/NF-κB signaling, making miR-4454 a candidate for treating metastatic human CRC.

Recruitment maneuver leads to increased expression of pro-inflammatory cytokines in acute respiratory distress syndrome.

Acute respiratory distress syndrome (ARDS) is a disease with high morbidity and mortality rates. The recruitment maneuver (RM) is one of the interventions used for ARDS patients suffering from severe hypoxemia. RM works by opening the atelectatic lungs using high transpulmonary pressure. RM has therefore been widely used for many years in patients with ARDS. However, because of the high transpulmonary pressure used in this intervention, there are concerns about both biotrauma and hemodynamic instability. To assess the effects of RM in ARDS, we conducted a study using three groups of pigs (n = 6 in each group): group I (control), group II (ARDS), and group III (ARDS with RM). After measuring the baseline values, ARDS was induced by deactivating the surfactant with 5% Tweens lavage. For pigs of group III, the RM protocol used was positive end-expiratory pressure (PEEP) of 25 cmH2O and peak pressure of 45 cmH2O. Gas exchange, hemodynamics, the expression of cytokines in serum, bronchoalveolar lavage fluid (BALF), and exhaled breath condensates (EBCs) were measured. The baseline measurements taken were similar across the three groups, and no significant difference was noted. After the induction of ARDS, PaO2 substantially decreased, while PaCO2, alveolar-arterial O2 gradient, pulmonary arterial pressure, lung water, level of cytokines in serum, EBCs, and BALF all increased. After RM, gas exchange and lung water level improved, but the level of cytokines in EBCs and BALF increased. Although RM led to an improvement in gas exchange, it may cause release of inflammatory cytokines in the EBCs and BALF.

FOXC1 Regulation of miR-31-5p Confers Oxaliplatin Resistance by Targeting LATS2 in Colorectal Cancer.

Colorectal cancer (CRC) is the second leading cause of cancer-related illness worldwide and one of the most common malignancies. Therefore, colorectal cancer research and cases have gained increasing attention. Oxaliplatin (OXA) is currently used in first-line chemotherapy to treat stage III and stage IV metastatic CRC. However, patients undergoing chemotherapy often develop resistance to chemo drugs being used. Evidence has confirmed that microRNAs regulate downstream genes in cancer biology and thereby have roles related to tumor growth, proliferation, invasion, angiogenesis, and multi-drug resistance. The aim of our study is to establish whether miR-31-5p is an oncogene in human colorectal cancers that are resistant to OXA and further confirm its malignant phenotype-associated target molecule. From the results of miRNA microarray assay, we establish that miR-31-5p expression was upregulated in oxaliplatin-resistant (OR)-LoVo cells compared with parental LoVo cells. Moreover, through in vitro and in vivo experiments, we demonstrate that miR-31-5p and large tumor suppressor kinase 2 (LATS2) were inversely related and that miR-31-5p and Forkhead box C1 (FOXC1) were positively correlated in the same LoVo or OR-LoVo cells. Importantly, we reveal a novel drug-resistance mechanism in which the transcription factor FOXC1 binds to the miR-31 promoter to increase the expression of miR31-5p and regulate LATS2 expression, resulting in cancer cell resistance to OXA. These results suggest that miR-31-5p may be a novel biomarker involved in drug resistance progression in CRC patients. Moreover, the FOXC1/miR31-5p/LATS2 drug-resistance mechanism provides new treatment strategies for CRC in clinical trials.

Inhibition of protein phosphatase 1 stimulates noncanonical ER stress eIF2α activation to enhance fisetin-induced chemosensitivity in HDAC inhibitor-resistant hepatocellular carcinoma cells.

Hepatocellular carcinoma (HCC) is a common fatal type of malignant tumor that has highly metastatic and recurrent properties. Fisetin is a natural flavonoid found in various vegetables and fruits which exhibits anti-cancer and anti-inflammatory properties, as well as other effects. Thus, we hypothesized that fisetin can act as an adjuvant therapy in cancer or drug-resistant cancer cells, and further investigated the molecular mechanisms underlying the development of drug-resistance in HCC cells. We found that fisetin effectively inhibited the cell viability of not only parental cells but also histone deacetylase inhibitors-resistant (HDACis-R) cells and enhanced the chemosensitivity of HCC cells. Interestingly, fisetin did not induce cell apoptosis through the activation of the endoplasmic reticulum (ER) stress sensor of protein kinase R (PKR)-like endoplasmic reticulum kinase, but rather through the non-canonical pathway of the protein phosphatase 1 (PP1)-mediated suppression of eIF2α phosphorylation. Moreover, fisetin-induced cell apoptosis was reversed by treatment with PP1 activator or eIF2α siRNA in HCC cells. Based on these observations, we suggest that PP1-eIF2α pathways are significantly involved in the effect of fisetin on HCC apoptosis. Thus, fisetin may act as a novel anticancer drug and new chemotherapy adjuvant which can improve the efficacy of chemotherapeutic agents and diminish their side-effects.