Current systemic management of metastatic renal cell carcinoma – first line and second line therapy

Signalling pathways involved in antitumoral effects of VIP in human renal cell carcinoma A498 cells: VIP induction of p53 expression

Vasoactive intestinal peptide (VIP) decreases cell proliferation through PI3K signalling and prevents tumour progression in clear renal cell carcinoma (RCC). Here we analyzed the signalling pathways that mediate such VIP effects by using human RCC A498 cells. The effects of treatment with 1 μM VIP and/or specific protein kinase inhibitors such as H89, Wortmannin and PD98059 were studied by cell adhesion assay, ELISA of VEGF165 and ROS production assays. Semiquantitative RT-PCR and western blot were performed to study p53 expression. VIP increased cell adhesion and ROS production, and decreased VEGF165 secretion through PI3K signalling. Moreover, VIP increased nuclear expression of tumour suppressor p53. VIP effects could be blocked by cell incubation with a specific p53 inhibitor, cyclin pifithrin-α hydrobromide (CPFT-αH). In conclusion, this study provides a p53-dependent mechanism by which VIP regulates cell proliferation in RCC development. It supports a potential usefulness of VIP in new therapies of RCC.

Evaluation of cancer treatment in the abdomen: Trends and advances

Response evaluation in Oncology has relied primarily on change in tumor size. Inconsistent results in the prediction of clinical outcome when size based criteria are used and the increasing role of targeted and loco-regional therapies have led to the development of new methods of response evaluation that are unrelated to change in tumor size. The goals of this review are to expose briefly the size based criteria and to present the non-size based approaches that are currently applicable in the clinical setting. Other paths that are still being explored are not discussed in details.

Down-regulation of CD74 inhibits growth and invasion in clear cell renal cell carcinoma through HIF-1α pathway

OBJECTIVES

To investigate the expression and function of CD74 in normal renal tissue and clear cell-renal cell carcinoma (ccRCC), as well as related renal tubule epithelial lines. We also analyzed the association between clinicopathological characteristics of ccRCCs and the expression levels of CD74.

METHODS

Immunostaining of CD74 was performed in 107 patients' renal tissue and cell lines. We evaluated the association between clinicopathological characteristics of ccRCC and CD74 levels using image analysis. CD74 expression levels were also analyzed by Western blot. Lentivirus-mediated CD74 knockdown inhibited the growth and invasion, of ccRCC cell lines 786-O in vitro and in vivo. Cell proliferation, apoptosis, and invasion as well as HIF-1α pathway-related proteins, were estimated by Western blot. All experiments were repeated at least 3 times.

RESULTS

Immunostaining and image analysis showed strong immunoreactions of CD74 in all patients' ccRCC tissue and malignant cell lines, while CD74 expression levels were associated with tumor grade (P = 0.013). Western blot indicated that ccRCC tissue and malignant cell lines expressed higher levels of CD74 and hypoxia inducible factor 1α (HIF-1α) than adjacent normal renal tissue and normal cell HK-2. Vitro and vivo tests demonstrated that lentivirus-mediated CD74 knockdown inhibited the proliferation of ccRCC cell lines, induced G1/S arrest and apoptosis, and inhibited invasion. Inhibition of CD74 resulted in down-regulation of HIF-1α pathway proteins.

CONCLUSIONS

CD74 was overexpressed in human ccRCCs and associated with tumor grade, and inhibition of CD74 produced ccRCC proliferation arrest, induced apoptosis, and inhibited invasion, which impinged on HIF-1α pathway-related proteins. It might represent a potential therapeutic target for ccRCC.