Jing-Min Zheng

Renal cell carcinoma (RCC) represents between 80 and 90% of primary renal cancers. While long non-coding RNAs (lncRNAs) are documented to modulate RCC deve

KDF1 has been reported to be correlated with carcinogenesis. However, its role and mechanism are far from clear. To explore the possible role and underlying mechanism of KDF1 in lung adenocarcinoma (LUAD), we investigated KDF1 expression in LUAD tissues and the influence of KDF1 in the phenotype of LUAD cells (A549 and PC-9) as well as the underlying mechanism. Compared to non-tumor lung epithelial cells, KDF1 was upregulated in the cancer cells of the majority of LUAD patients, and its expression was correlated with tumor size. Patients with enhanced KDF1 in cancer cells (compared with paired adjacent non-neoplastic lung epithelial cells) had shorter overall survival than patients with no increased KDF1 in cancer cells. Knockdown of KDF1 inhibited the migration, proliferation and invasion of LUAD cells in vitro. And overexpression of KDF1 increased the growth of the subcutaneous tumors in mice. In terms of molecular mechanisms, overexpression of KDF1 induced the expression of AKT, p-AKT and p-STAT3. In KDF1-overexpressing A549 cells, inhibition of the STAT3 pathway decreased the level of AKT and p-AKT, whereas inhibition of the AKT pathway had no effect on the activation of STAT3. Inhibition of STAT3 or AKT pathways reversed the promoting effects of KDF1 overexpression on the LUAD cell phenotype and STAT3 inhibition appeared to have a better effect. Finally, in the cancer cells of LUAD tumor samples, the KDF1 level was observed to correlate positively with the level of p-STAT3. All these findings suggest that KDF1, which activates STAT3 and the downstream AKT pathway in LUAD, acts as a tumor-promoting factor and may represent a therapeutic target.

Background: Contradictive results about the direct role of C5a/C5aR1 axis in different cancer cells have been reported. The direct effect of C5a on human renal cell carcinoma (RCC) cells and the underlying mechanism are not clear. The aim of this study is to investigate the role of C5a/C5aR1 axis in RCC cells and its working mechanism. Methods: RCC cells were infected with lentivirus Lenti-C5a, which was designed to over-express secretory C5a in the cells, or directly treated with recombinant C5a, the influence of these treatments in the cells and the underlying mechanism were explored. Results: Transfection of RCC cells with Lenti-C5a markedly increased the production of C5a and significantly increased the proliferation, migration, and invasion of RCC cells, but direct addition of C5a to the cell culture medium had no such effects though it indeed induced a transient intracellular calcium rise. RCC cells were found to express carboxypeptidase D and M, which reportedly to inactivate C5a. Also, the RCC cells stably transfected with Lenti-C5a produced larger transgrafted tumors in nude mice compared with the non-transfected or control virus transfected cells. In addition, over-expression of C5a significantly increased the expression and phosphorylation of STAT3 as well as the phosphorylated JNK level. Furthermore, the effect of C5a over-expression on RCC cells’ proliferation, migration, and invasion could be blocked by Stattic, a STAT3-specific inhibitor. Conclusion: Chronic over-activation of C5a/C5aR1 axis could directly increase RCC cells’ proliferation, migration, and invasion and thus contribute directly to the progression of the disease. Over-activation of STAT3 pathway is among the underlying mechanism.

KDF1 has been identified as a key regulator of epidermal proliferation and differentiation, but it is unknown whether KDF1 is involved in the pathogenesis of malignancy. No study has reported the expression and function of KDF1 in renal cancer. To explore the pathologic significance of KDF1 in clear cell renal cell carcinoma (ccRCC), the expression level of KDF1 protein in the tumor tissue of ccRCC patients was examined by immunohistochemistry and Western blot while the expression level of KDF1 mRNA was analyzed by using the data from TCGA database. In vitro cell experiments and allogeneic tumor transplantation tests were performed to determine the effects of altered KDF1 expression on the phenotype of ccRCC cells. Both the KDF1 mRNA and protein were found to be decreasingly expressed in the tumor tissue of ccRCC patients when compared with the adjacent non-tumor control tissue. The expression level of KDF1 in the tumor tissue was found to correlate negatively with the tumor grade. Patients with higher KDF1 in the tumor tissue were found to have longer overall survival and disease-specific survival time. KDF1 was shown to be an independent factor influencing the disease-specific survival of the ccRCC patients. Overexpression of KDF1 was found to inhibit the proliferation, migration and invasion of ccRCC cells, which could be reversed by decreasing the expression of KDF1 again. ccRCC cells with KDF1 overexpression were found to produce smaller transgrafted tumors. These results support the idea that KDF1 is involved in ccRCC and may function as a tumor suppressor.

The C3a receptor (C3aR) has been reported to be involved in various physiological and pathological processes, including the regulation of cellular structure development. Expression of C3aR has been reported in podocytes; however, data concerning the role of C3aR in podocyte morphology is scarce. The aim of the present study was to examine the effect of C3aR activation on the architectural development of podocytes. An immortal human podocyte line (HPC) was transfected with a C3a expression lentivirus vector or recombinant C3a. SB290157 was used to block the activation of C3aR. The expression of C3a in HPC cells was analyzed by reverse transcription‑quantitative PCR (RT‑qPCR) and ELISAs. Phase contrast and fluorescence microscopy were used to observe the morphology of the podocytes. The adhesive ability of HPC cells was analyzed using an attachment assay. RT‑qPCR, cyto‑immunofluorescence and western blotting were used to determine the expression levels of the adhesion‑associated genes. The expression levels of carboxypeptidases in HPC cells was also detected by RT‑qPCR. Compared with the untransfected and control virus‑transfected HPC cells, the C3a‑overexpressing cells (HPC‑C3a) failed to expand their cell bodies and develop an arborized appearance in the process of maturation, which the control cells exhibited. In addition, HPC‑C3a cells presented with decreased adhesive capacity, altered focal adhesion (FA) plaques and decreased expression of FA‑associated genes. These effects were blocked by a C3aR antagonist; however, the addition of purified C3a could not completely mimic the effects of C3a overexpression. Furthermore, HPC cells expressed carboxypeptidases, which have been reported to be able to inactivate C3a. In summary, the results demonstrated that sustained C3aR activation impaired the morphological maturation of HPC cells, which may be associated with the altered expression of FA‑associated genes and impaired FA. Since chronic complement activation has been reported in renal diseases, which indicate sustained C3aR activation in renal cells, including podocytes and podocyte progenitors, the possible role of C3aR in the dysregulation of podocyte architecture and podocyte regeneration requires further research.

Background Increasing evidences suggest that anaphylotoxin-induced signaling is involved in tumor pathogenesis, but the exact role of C3a/C3aR signaling in clear cell renal cell carcinoma (ccRCC) still remains to be investigated. The aim of the study was to investigate the pathological significance of C3a/C3aR signaling in ccRCC. Methods The expression of C3aR and C3 mRNA in the tumor tissues of ccRCC patients were analyzed by using the data from TCGA database. The expression of C3aR and C3c protein in the tumor tissues of another 129 ccRCC patients were examined by immunohistochemistry. Results Compared with the normal controls, both C3aR and C3 mRNA increased in the tumor tissues. Patients with higher C3 mRNA had shorter survival time. Immunostaining for C3aR and C3c also increased in the tumor tissues when compared with the adjacent normal renal tissues. Higher level of C3aR in the tumor cells and C3c in the tumor tissues were found to be associated with indices reflecting poor prognosis including higher tumor grade, the presence of necrosis in tumor tissues and shorter survival time. Besides, the level of C3aR in the tumor cells and C3c in the tumor tissues were found to correlate with the level of Vimentin, E-Cadherin and the ratio of Ki-67 positive tumor cells. Conclusions These results support the idea that C3aR signaling is over-activated in the tumor cells and may contribute to the progression of ccRCC. Inducing EMT and promoting the proliferation of tumor cells might be among the mechanisms underlying the role of C3aR signaling in ccRCC.

Aims The aim of this study was to get a full view of the changes of urinary complement activation products in the development of diabetic nephropathy and explore their possible significance in the disease process. Materials and methods Sixty‐two patients at different stages of diabetic nephropathy,20 diabetes patients without nephropathy and 20 healthy persons were enrolled. Urinary complement activation products including C3a, C5a and C5b‐9 were measured and their associations with the progression of the disease were analyzed. Results The urinary complement activation products increased markedly since the proteinuria stage and paralleled with the progression of diabetic nephropathy. Severer renal tubular damage was observed in patients with higher levels of urinary complement activation products. The urinary complement activation products levels correlated closely with renal tubulointerstitial injury score and relative tubular interstitial volume (A reviewer commented that there was no clinical importance of comparisons between urinary biomarkers (NAG, NGAL and RBP) of interstitial damage and urinary CAPs, because we have already compared actual interstitial injury. Accordingly, we have deleted the description of comparisons between urinary biomarkers (including NAG, NGAL and RBP) of interstitial damage and urinary CAPs in the abstract). Multivariate regression analysis revealed that elevated urinary complement activation products were independent risk factors for the tubular injury in diabetic nephropathy patients. Conclusions Urinary complement activation might have a role in renal tubular interstitial injury in patients with diabetic nephropathy, especially in the patients at later stage of the disease.