Abemaciclib (CDK4/6 Inhibitor) Blockade Induces Cytotoxicity in Human Anaplastic Thyroid Carcinoma Cells.

BACKGROUND: Thyroid cancer is the most prevalent endocrine malignancies globally. Anaplastic thyroid carcinoma (ATC) accounts for 1-3% of all Thyroid cancer. The evidence showed that ATC is a highly invasive solid tumor with poor prognosis. Despite conventional chemotherapy treatments, a considerable number of patients show developing resistance to therapeutic agents and tumor relapse. The aim of this study was the investigation anti-tumor effect of Abemaciclib (novel targeted cancer therapy drug) on Anaplastic Thyroid carcinoma SW1736 and C643 cell lines. METHODS: SW1736 and C643 cell lines were treated by desire concentrations of Abemaciclib (0, 1, 2.5, 5, 10, and 20 µM) and cell viability was measured by MTT assay. Also, Anoikis resistance assay was conducted for non-adherent the cells in the exposure of Abemaciclib. The gene expression of apoptotic and anti-apoptotic genes was conducted by quantitative Real-time PCR. RESULTS: Abemaciclib at the concentration of 10 and 20 µM effectively reduced cell proliferation and growth of the ATC cells compared to the control (p=0.000). Furthermore, we showed that 10 and 20 µM doses of the Abemaciclib inhibited the non-adherent ATC cells which were resistant to Anoikis death significantly (p=0.001). Moreover, we demonstrated this targeted therapy significantly reduced anti-apoptotic gene expression levels (BCL2 and CMYC) (p<0.05) and increased apoptotic gene expressions such as P21 and BAX (p<0.05). CONCLUSION: Our data suggested that Abemaciclib can be utilized as a novel therapeutic agent in ATC cancer. Further in vivo and in vitro investigations are needed to evaluate molecular and clinical mechanisms of Abemaciclib.

PARP-1 Overexpression as an Independent Prognostic Factor in Adult Non-M3 Acute Myeloid Leukemia.

AIMS: Poly (ADP-ribose) polymerase-1 (PARP-1) plays an important role in the repair of damaged DNA and has prognostic significance in a variety of human malignancies. However, little is known about its expression levels and clinical implication in patients with acute myeloid leukemia (AML). MATERIALS AND METHODS: Quantitative reverse transcription-polymerase chain reaction was done to evaluate PARP-1 expression levels in the bone marrow of 65 patients with non-M3 AML and 54 healthy counterparts. The correlation of PARP-1 expression with clinicopathological features of non-M3 AML patients was also analyzed. RESULTS: Non-M3 AML patients have higher PARP-1 expression than the healthy controls (p < 0.01). Patients with adverse cytogenetic risk have higher PARP-1 expression than other cytogenetic risk groups (p = 0.004). The PARP-1 median expression level divided AML patients into PARP-1 low-expressed and PARP-1 high-expressed groups. High expression levels of PARP-1 were associated with worse overall survival (OS) (p = 0.01) and relapse-free survival (RFS) (p = 0.005). Moreover, multivariate analysis revealed that high PARP-1 expression was an independent risk factor for both OS and RFS. CONCLUSIONS: Our results suggest that PARP-1 overexpression may define an important risk factor in non-M3 AML patients and PARP-1 is a potential therapeutic target for AML treatment.

Low Expression of Long Noncoding RNA IRAIN Is Associated with Poor Prognosis in Non-M3 Acute Myeloid Leukemia Patients.

AIMS: Deregulation of the long noncoding RNA IRAIN has been identified in several cancers. However, the expression pattern of IRAIN and its clinical implication in acute myeloid leukemia (AML) are unknown. The purpose of this study was to investigate the expression status of IRAIN and its clinical significance in non-M3 AML patients. METHODS: Quantitative reverse transcription-polymerase chain reaction was performed to examine IRAIN transcript levels in 64 de novo non-M3 AML patients and 51 healthy controls. The association of IRAIN expression with clinicopathological factors was statistically analyzed. RESULTS: Compared with the controls, IRAIN was significantly downregulated in non-M3 AML patients (p < 0.001). The median of IRAIN expression divided the non-M3 AML patients into IRAIN low-expressing (IRAINlow) and IRAIN high-expressing (IRAINhigh) groups. The IRAINlow group tended to have higher white blood cell count and blast counts and had markedly shorter overall survival (OS) and relapse-free survival (RFS) (p = 0.044 and 0.009, respectively). In addition, patients with refractory response to chemotherapies and those with subsequent relapse had lower initial IRAIN expression. Multivariate analysis further identified IRAIN transcript levels as an independent prognostic factor for both RFS and OS. CONCLUSIONS: Our finding suggests that IRAIN transcript levels may be a useful biomarker for the prognosis of non-M3 AML patients.

Pharmacological evidence for the involvement of adenosine triphosphate sensitive potassium channels in chloroquine-induced itch in mice.

BACKGROUND: Chloroquine (CQ) evokes itch in human and scratching behavior in rodents through a histamine-independent pathway. Chloroquine directly excites peripheral sensory neurons which convey itch signals to the central nervous system. It has been revealed that ATP-sensitive potassium channels (KATP channels) are important in regulating neuronal excitability. Thus, we aimed to investigate the involvement of KATP channels in CQ-induced itch which may also reveal a linkage between metabolic state of cells and itch. METHODS: Intradermal (id) injection of CQ at dose of 400µg/site induces the scratching behavior. KATP channel openers, diazoxide (DZX) and minoxidil (MIN), and a KATP channel blocker, glibenclamide (GLI), were administered intraperitoneally (ip) before CQ. Then the behavior was recorded for 30min, in an unmanned condition, and the scratching bouts were counted by an expert observer who was blinded to the experiments. Furthermore, quantitative reverse transcription-PCR (qRT-PCR) was used to investigate the possible changes in dermal expression of Kcnj8 and Kcnj11, the genes encoding the KATP channels. RESULTS: Our results show that either DZX (10mg/kg, ip) or MIN (10mg/kg, ip) significantly attenuated CQ-induced scratching behavior in mice. Moreover, pretreatment with GLI (3mg/kg, ip) significantly reversed the anti-pruritic effects of DZX and MIN. Our finding of qRT-PCR analysis also show that the expression of Kcnj8 is decreased after CQ injection. CONCLUSIONS: We suggest that KATP channels are possibly involved in CQ-induced itch. While, further studies will be significant to better elucidate the association of metabolic state of cells and itch.

Tropisetron suppresses colitis-associated cancer in a mouse model in the remission stage.

Patients with inflammatory bowel disease (IBD) have a high risk for development of colitis-associated cancer (CAC). Serotonin is a neurotransmitter produced by enterochromaffin cells of the intestine. Serotonin and its receptors, mainly 5-HT3 receptor, are overexpressed in IBD and promote development of CAC through production of inflammatory cytokines. In the present study, we demonstrated the in vivo activity of tropisetron, a 5-HT3 receptor antagonist, against experimental CAC. CAC was induced by azoxymethane (AOM)/dextran sodium sulfate (DDS) in BALB/c mice. The histopathology of colon tissue was performed. Beta-catenin and Cox-2 expression was evaluated by immunohistochemistry as well as quantitative reverse transcription-PCR (qRT-PCR). Alterations in the expression of 5-HT3 receptor and inflammatory-associated genes such as Il-1ß, Tnf-α, Tlr4 and Myd88 were determined by qRT-PCR. Our results showed that tumor development in tropisetron-treated CAC group was significantly lower than the controls. The qRT-PCR analysis demonstrated that the expression of 5-HT3 receptor was significantly increased following CAC induction. In addition, tropisetron reduced expression of ß-catenin and Cox-2 in the CAC experimental group. The levels of Il-1ß, Tnf-α, Tlr4 and Myd88 were significantly decreased upon tropisetron treatment in the AOM/DSS group. Taken together, our data show that tropisetron inhibits development of CAC probably by attenuation of inflammatory reactions in the colitis.

Differential expression of human homeodomain TGIFLX in brain tumor cell lines.

Glioblastoma is the most common and the most lethal primary brain cancer. This malignancy is highly locally invasive, rarely metastatic and resistant to current therapies. Little is known about the distinct molecular biology of glioblastoma multiforme (GBM) in terms of initiation and progression. So far, several molecular mechanisms have been suggested to implicate in GBM development. Homeodomain (HD) transcription factors play central roles in the expression of genomic information in all known eukaryotes. The TGIFX homeobox gene was originally discovered in human adult testes. Our previous study showed implications of TGIFLX in prostate cancer and azoospermia, although the molecular mechanism by which TGIFLX acts is unknown. Moreover, studies reported that HD proteins are involved in normal and abnormal brain developments. We examined the expression pattern of TGIFLX in different human brain tumor cell lines including U87MG, A172, Daoy and 1321N1. Interestingly, real time RT-PCR and western blot analysis revealed a high level of TGIFLX expression in A172 cells but not in the other cell lines. We subsequently cloned the entire coding sequence of TGIFLX gene into the pEGFP-N1 vector, eukaryotic expression vector encoding eGFP, and transfected into the U-87 MG cell line. The TGIFLX-GFP expression was confirmed by real time RT-PCR and UV-microscopic analysis. Upon transfection into U87 cells, fusion protein TGIFLX-GFP was found to locate mainly in the nucleus. This is the first report to determine the nuclear localization of TGIFLX and evaluation of its expression level between different brain tumor cell lines. Our data also suggest that TGIFLX gene dysregulation could be involved in the pathogenesis of some human brain tumors.

Identification of novel p53 target genes by cDNA AFLP in glioblastoma cells.

The p53 plays critical role in cellular functions such as cell cycle arrest and apoptosis. We overexpressed wild-type p53 (wt-p53) in U87 glioblastoma cells via recombinant adenovirus Ad-GFP-P53 which encodes p53 and green fluorescent protein. The transcript profiles were investigated using cDNA amplified fragment length polymorphism approach. Semi-quantitative RT-PCR and DNA sequencing results for the selected genes showed that Cathepsin B and cell cycle associated protein-1 or Caprin-I, genes were suppressed whereas Annexin-II gene overexpressed in response to the overexpression of wt-p53 gene. Our results suggest that these genes could be important mediators of p53-dependent tumor growth suppression in glioblastoma.