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To prepare peptide-modified chitosan tetramethylprazine nanoparticles(FGF-CS-TMP-NPS) and investigate its reversal effect on multidrug resistance in tumor cells. The pEGF-CS-TMP-NPs were prepared by ion crosslinking method, and their physicochemical properties were investigated. Western blot was used to detect the expression levels of epidermal growth factor receptor(EGFR)(MCF-7, MCF-7/ADR, K562 and K562/ADR) and drug-resistant related protein P-gp. MCF-7/ADR and K562/ADR were selected as cell models. The cytotoxicity of pEGF-CS-TMP-NPs, the multiple of cell resistance to adriamycin, the reversal resistance index of pEGF-CS-TMP-NPs to doxorubicin and the sensitization of pEGF-CS-TMP-NPs to doxorubicin were detected by MTT assay. After MCF-7/ADR and K562/ADR were treated with pEGF-CS-TMP-NPs, the expression changes of P-gp were detected by Western blot. The encapsulation efficiency and drug loading of pEGF-CS-TMP-NPs were 37.66%± 0.53% and 3.25%± 0.34% respectively in HPLC. The nanoparticles showed an average particle size of(150.50±9.3) nm, polymer dispersity index of(0.059±0.007) and Zeta potential of(19.30±2.02) mV as detected by laser particle size analyzer. The nanoparticles were spherical and well dispersed under transmission electron microscope. Western blot results showed that EGFR was positively expressed in MCF-7 and MCF-7/ADR cells, while negatively expressed in K562 and K562/ADR cells. P-gp was highly expressed in MCF-7/ADR and K562/ADR, while negatively expressed in MCF-7 and K562. pEGF-CS-TMP-NPs had a weak effect on MCF-7/ADR and K562/ADR. The adriamycin resistance of MCF-7/ADR cells was 108.36 times, and that of K562/ADR cells was more than 100 times. When IC_(85) of pEGF-CS-TMP-NPs was used as the administration concentration, the reversion index of MCF-7/ADR and K562/ADR cells was 3.68 and 1.87, respectively. pEGF-CS-TMP-NPs could enhance the sensitivity of adriamycin to MCF-7/ADR cells in a positive correlation with the concentration, and the sensitivity was significantly higher than that of K562/ADR cells. Western blot results showed that the expression level of P-gp in MCF-7/ADR cells decreased significantly after treatment with pEGF-CS-TMP-NPs, while the expression level of P-gp in K562/ADR cells did not change significantly. Experimental results show that pEGF-CS-TMP-NPs have an active targeting effect on MCF-7/ADR cells with high EGFR expression, and can effectively reverse the multidrug resistance of MCF-7/ADR cells. Active targeting effect is related to the peptides modification of nanoparticles, and the mechanism of reversing tumor MDR may be achieved by down-regulating the expression level of P-gp.

Objective: To investigate the relationship between renal clear cell carcinoma and type 2 diabetes mellitus (DM)., Methods: Two hundreds and sixty-four patients with renal clear cell carcinoma and four hundred controls who suffered from non-urinary system, non-neoplastic or non-hormone-related disorders, were enrolled from January 2008 to December 2012. The incidence of diabetes between the 2 groups and the relationship between renal clear cell carcinoma and duration of diabetes were compared, moreover, renal clear cell carcinoma patients with DM were compared with patients without DM for their clinical features, laboratory examinations and histological characteristics., Results: The comparison of renal clear cell carcinoma group and control group: the incidence of DM in the two groups were 19.7% and 12.8% respectively, and the difference was significant (χ(2) = 5.86, P < 0.05, OR = 1.68). In the renal clear cell carcinoma group, the proportion of patients with DM diagnosed within 2-4 years was 4.92%, which were significant higher than those in the control group 1.70% (χ(2) = 5.49, P < 0.05, OR = 2.91). And men with diabetes had high occurrence risk 86% of renal clear cell carcinoma (OR = 1.86, 95%CI: 1.09-3.15). The comparison of diabetes patients subgroup and non-diabetic patients subgroup in renal clear cell carcinoma group: in respect of clinical features, greatest tumor diameter in the two subgroups were (4.9 ± 2.3) cm and (4.2 ± 2.1) cm respectively, and the difference was significant (t = 1.96, P < 0.05). However, there was no significant difference in terms of age, gender and cancer location between the two subgroups (P > 0.05). In respect of laboratory examinations, serum creatinine in the two subgroups were (72 ± 20) µmol/L and (65 ± 17) µmol/L, and the difference was significant (t = 2.34, P < 0.05); serum urea nitrogen in the 2 subgroups were (7.1 ± 2.1) mmol/L and (6.0 ± 1.5) mmol/L respectively, and the difference was significant too (t = 1.47, P < 0.05). In respect of histological characteristics, the proportion of well differentiated clear cell carcinoma were 80.8% and 81.1% respectively, and the difference was significant (χ(2) = 4.23, P < 0.05). The proportion of stage II were 25.0% and 27.8% respectively and the difference was significant (χ(2) = 4.08, P < 0.05)., Conclusions: DM is closely related with renal clear cell carcinoma and DM may be a possible risk factor for the tumor. And for elderly patients with diabetes who appear waist discomfort or hematuria, a careful examination of kidney is important to make early diagnosis, give timely treatment and improve survival prognosis.