Anti-Cyclin A1 (R436) Anticorpo (A25113)

BACKGROUND:

T-cell immunoglobulin domain and mucin domain 4 (TIM-4) is exclusively expressed in antigen-presenting cells and involved in immune regulation. However, the role of TIM-4 expressed in tumour cells remains completely unknown.

METHODS:

Immunohistochemistry staining was used to examine TIM-4 or Ki-67 expression in tumour tissues. Real-time PCR or RT-PCR was performed to detect TIM-4 mRNA expression. Lung cancer cell growth and proliferation were conducted by CCK-8 assay and EdU staining. Cell cycle progression was analysed by flow cytometry. The PCNA and cell cycle-related proteins were verified by western blot. Co-IP assay was used to identify the interaction of TIM-4 and integrin αvβ3. The efficacy of TIM-4 in vivo was evaluated using xenograft tumour model.

RESULTS:

The expression of TIM-4 in non-small-cell lung cancer (NSCLC) tissues was significantly higher than that of the adjacent tissues. Enhanced TIM-4 expression was negatively correlated with histological differentiation of lung carcinoma and lifespan of patients. Overexpression of TIM-4 promoted lung cancer cell growth and proliferation, and upregulated the expression of PCNA, cyclin A, cyclin B1 and cyclin D1, accompanied by accumulation of lung cancer cells in S phase. Interestingly, Arg-Gly-Asp (RGD) motif mutation abolished the effect of TIM-4 on lung cancer cells, which was further verified by tumour xenografts in mice. Furthermore, we found that TIM-4 interacted with αvβ3 integrin through RGD motif.

CONCLUSIONS:

This finding suggests that TIM-4 might be a potential biomarker for NSCLC that promotes lung cancer progression by RGD motif.

PURPOSE:

Cryptotanshinone is a major active component of Salvia miltiorrhiza, which is often used as Chinese herbal medicine in cancer therapy. Here, we systematically assessed the anti-tumor effect of Cryptotanshinone on two melanoma cell lines with low/high-metastatic capacity (B16/B16BL6).

METHODS:

MTT and LDH assays were used to evaluate cell growth and cytotoxicity. We assessed the effect of Cryptotanshinone on cell apoptosis or proliferation by Annexin V, TUNEL or BrdU assay. Cell cycle distribution was detected by flow cytometry. The integrity of cell cycle checkpoints was determined by mutational analyses of B-RAF and N-RAS, and the expression of cell cycle-associated proteins by western blotting.

RESULTS:

Treatment with Cryptotanshinone had no obvious effect on cell apoptosis but significantly inhibited cell proliferation. Cryptotanshinone slightly increased the expression of p53, Chk1, and Chk2 in both B16 and B16BL6. Interestingly, Cryptotanshinone induced G1 arrest with a concomitant increase in p21 expression in B16BL6 cells. However, in B16 cells, Cryptotanshinone induced the G2/M arrest through its induction of Cdc25c. Regulation of Cyclin A1, Cyclin B1 and Cdk1/cdc2 expression might contribute to the different cell cycle patterns in B16 and B16BL6 after Cryptotanshinone treatment.

CONCLUSIONS:

Cryptotanshinone could have diverse effects on cell cycle events in melanoma cell lines with different metastatic capacity. This property might offer an opportunity to study underlying mechanisms for the different antitumor effects of administered Cryptotanshinone in B16 and B16BL6 cells.