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T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive type of blood malignancy, deriving from T-cell progenitors in the thymus, and comprises 10-15% of pediatric and 25% of adult primary ALL cases. Despite advances, 20% of pediatric and the majority of adult patients with T-ALL succumb to mortality from resistant or relapsed disease, and the survival rate for patients with resistant or relapsed T-ALL remains poor. Alterations in the expression of Forkhead box protein M1 (FoxM1) have been detected in several types of cancer, and the inhibition of FoxM1 has been investigated as therapeutic strategy in cancer. The present study investigated the effects of the inhibition of FoxM1 by thiostrepton in human T-ALL Jurkat cells. The cells were treated with different concentrations of thiostrepton, either alone or in combination with doxorubicin. Cell viability was measured using CCK-8 assays and the cell cycle distribution, apoptosis and cell-associated mean fluorescence intensity of intracellular doxorubicin were assessed using flow cytometric analysis. The mRNA and protein expression levels were detected by reverse transcription-quantitative polymerase chain reaction and western blot analyses. The inhibition of FoxM1 by thiostrepton significantly decreased the proliferation of the Jurkat cells proliferation in a time- and dose-dependent manner. Cell arrest at the G2/M phase, and apoptosis was significantly increased in the thiostrepton-treated Jurkat cells. Thiostrepton reduced the half maximal inhibitory concentration of doxorubicin in the Jurkat cells, and significantly enhanced the cytotoxicity of doxorubicin within the Jurkat cells by enhancing doxorubicin-induced apoptosis and increasing the accumulation of intracellular doxorubicin. Furthermore, the inhibition of FoxM1 by thiostrepton enhanced doxorubicin-induced apoptosis, possibly through a caspase-3-dependent pathway, and increased the accumuation of intracellular doxorubicin, possibly through downregulating the expression of glutathione S-transferase pi. Collectively, the results of the present study suggested that targeting FoxM1 with thiostrepton resulted in potent antileukemia activity and chemosensitizing effects in human T-ALL Jurkat cells. [ABSTRACT FROM AUTHOR]

CD4+ T cells in rheumatoid arthritis (RA) express growth signaling pathway in association with deregulated growth and resistance to apoptosis. The janus kinase (Jak) 3 and signal transducer and activator of transcription (STAT) pathway play a critical role in interleukin-2 (IL-2)-induced CD4+ T cell proliferation. The present study aimed to explore the anti-cell proliferation mechanism of curcumol, a pure monomer extracted from Chinese medical plant Rhizoma curcumae. Cell proliferation was determined using WST-1 assay after curcumol treatment. The cell cycle distribution and Bcl-2 protein expression were assessed by flow cytometry. The cellular morphology of apoptosis was evaluated by Hoechst 33258 staining. The expressions of phosphorylated-Jak3 (p-Jak3), p-STAT3, and p-STAT5a following IL-2 stimulation were determined by western blot analysis. The Electrophoretic Mobility Shift Assay was used to detect the DNA binding activities of transcription factors STAT3 and STAT5. The study results showed that curcumol could inhibit the IL-2-induced Jurkat cell proliferation in a concentration- and time-dependent manner in vitro. Curcumol could cause cell cycle arrest at the S phase, induce cell apoptosis, and inhibit the expression of Bcl-2 in a dose-dependent manner. Curcumol at 50µg/mL and Jak3 inhibitor ZM39923 could inhibit the phosphorylation of Jak3 and STAT5a. In conclusion, the underlying mechanism of curcumol on suppressing CD4+ T cell proliferation and inducing apoptosis might partly be mediated by inhibition of Jak3-STAT5-related molecular activities and Bcl-2 expression, respectively; further studies are required in vivo to test the use of curcumol as a promising therapeutic option for RA. [ABSTRACT FROM AUTHOR]

Background: Apoptosis is important for regulating spermatogenesis. The protein mRHBDD1 (mouse homolog of human RHBDD1)/rRHBDD1 (rat homolog of human RHBDD1) is highly expressed in the testis and is involved in apoptosis of spermatogonia. GC-1, a spermatogonia cell line, has the capacity to differentiate into spermatids within the seminiferous tubules. We constructed mRHBDD1 knockdown GC-1 cells and evaluated their capacity to differentiate into spermatids in mouse seminiferous tubules. Results: Stable mRHBDD1 knockdown GC-1 cells were sensitive to apoptotic stimuli, PS341 and UV irradiation. In vitro, they survived and proliferated normally. However, they lost the ability to survive and differentiate in mouse seminiferous tubules. Conclusion: Our findings suggest that mRHBDD1 may be associated with mammalian spermatogenesis. [ABSTRACT FROM AUTHOR]

As influencing factors of genesis and progression in several types of human tumor, microRNAs (miRs) serves roles in the regulation of tumor cell viability, migration, and apoptosis. The present research aimed to investigate the association between the function of miR‑100‑5p and renal cell carcinoma (RCC). miR‑100‑5p expression was determined in RCC tissue and paired normal tissue samples using reverse transcription‑quantitative polymerase chain reaction. To assess the effects of miR‑100‑5p on cell viability, migration and apoptosis, multiple methods were used, including scratch wound assays, MTT assays, and flow cytometry. It was demonstrated that miR‑100‑5p was significantly upregulated in RCC tissue compared with in normal adjacent tissue samples. Furthermore, the viability and migration of 786‑O and, ACHN cells tranfected with miR‑100‑5p was significantly increased compared with the negative control group. In addition, miR‑100‑5p‑transfected 786‑O and ACHN cells demonstrated significantly reduced cellular apoptotic rates compared with the negative control group. To the best of our knowledge, the present study is the first to report an association between miR‑100‑5p and RCC. The results of the current study suggest that tumor oncogene miR‑100‑5p could be used as a diagnostic biomarker for RCC. [ABSTRACT FROM AUTHOR]

Berberine is a well-known component of the Chinese herbal medicine Huanglian (Coptis chinensis), and is capable of inhibiting the proliferation of multiple cancer cell lines. However, information available regarding the effect of berberine on prostate cancer cell growth is limited. In the present study, LnCaP and PC-3 human prostate cancer cell lines were selected as in vitro models in order to assess the efficacy of berberine as an anticancer agent. A cell proliferation assay demonstrated that berberine inhibited cell growth in a dose-and time-dependent manner. Further investigation revealed berberine significantly accumulated inside cells that were in the G1 phase of the cell cycle and enhanced apoptosis. Western blot analysis demonstrated that berberine inhibited the expression of prostate-specific antigen and the activation of epidermal growth factor receptor (EGFR), and it attenuated EGFR activation following EGF treatment in vitro. In conclusion, the results indicate that berberine inhibits the proliferation of prostate cancer cells through apoptosis and/or cell cycle arrest by inactivation of the EGFR signaling pathway. [ABSTRACT FROM AUTHOR]