SGT1 is required in PcINF1/SRC2-1 induced pepper defense response by interacting with SRC2-1.

PcINF1 was previously found to induce pepper defense response by interacting with SRC2-1, but the underlying mechanism remains uninvestigated. Herein, we describe the involvement of SGT1 in the PcINF1/SRC2-1-induced immunity. SGT1 was observed to be up-regulated by Phytophthora capsici inoculation and synergistically transient overexpression of PcINF1/SRC2-1 in pepper plants. SGT1-silencing compromised HR cell death, blocked H2O2 accumulation, and downregulated HR-associated and hormones-dependent marker genes' expression triggered by PcINF1/SRC2-1 co-overexpression. The interaction between SRC2-1 and SGT1 was found by the yeast two hybrid system and was further confirmed by bimolecular fluorescence complementation and co-immunoprecipitation analyses. The SGT1/SRC2-1 interaction was enhanced by transient overexpression of PcINF1 and Phytophthora capsici inoculation, and SGT1-silencing attenuated PcINF1/SRC2-1 interaction. Additionally, by modulating subcellular localizations of SRC2-1, SGT1, and the interacting complex of SGT1/SRC2-1, it was revealed that exclusive nuclear targeting of the SGT1/SRC2-1 complex blocks immunity triggered by formation of SGT1/SRC2-1, and a translocation of the SGT1/SRC2-1 complex from the plasma membrane and cytoplasm to the nuclei upon the inoculation of P. capsici. Our data demonstrate that the SGT1/SRC2-1 interaction, and its nucleocytoplasmic partitioning, is involved in pepper's immunity against P. capsici, thus providing a molecular link between Ca(2+) signaling associated SRC2-1 and SGT1-mediated defense signaling.

Malignant transformation of sinonasal inverted papilloma: A retrospective analysis of 32 cases.

Sinonasal inverted papillomas (SNIPs) are derived from the benign tumors of the epithelial cells and have the potential to recur and exhibit malignant characteristics. The aim of the present study was to investigate the clinicopathological features and prognosis of patients with malignant transformation of SNIP. A total of 32 consecutive cases, who were patients at the Department of Otorhinolaryngology Head and Neck Surgery, Tianjin Huanhu Hospital from January 1991 to January 2008, were retrospectively reviewed. Survival rates and prognostic factors were calculated using the Kaplan-Meier method and multivariate Cox model survival analysis. The malignancy accounted for 8.99% of all types of SNIP. There were 25 males and seven females, and the median age of onset was 56.5 years. The sites of tumor included 22 in the nasal cavity and ethmoid sinuses, and 10 in the maxillary sinus. The tumors included 21 high-grade tumors, eight intermediate-grade tumors and three low-grade tumors. The number of patients with T1, T2, T3 and T4 stage disease was three, 10, 16 and three, respectively, according to the American Joint Committee on Cancer staging method. Based on the percentage of malignant cells in the entire tumor tissue, five patients had grade I tumors, five had grade II, eight had grade III and14 had grade IV. Among the 32 patients, three cases exhibited distant metastasis, and 19 patients underwent surgery plus postoperative radiotherapy, 10 underwent surgery alone and three underwent radiotherapy alone. The 5-year survival rate was 72.5% and the median overall survival time was 62.2 months. Kaplan-Meier univariate survival analysis indicated that the clinical stage and treatment method were prognostic factors, and multivariate Cox model survival analysis confirmed that the clinical stage and treatment method were independent factors for overall survival (relative risk: 4.211 and 0.312, respectively; P<0.05 for both). T3 and T4 staging and mono-treatment were associated with poor patient survival. Overall, the present study identified that the morbidity of SNIP-associated malignancy was low, the clinicopathological features were not specific, and the prognosis was improved compared with other types of sinonasal squamous cell carcinoma. The clinical stage and treatment method were found to affect the prognosis, and surgery plus postoperative radiotherapy was the predominant form of treatment. The present study may improve the understanding of the prognosis for patients with malignant SNIP in the future.

[Malignant transformation of sinonasal inverted papilloma: retrospective analysis of 32 cases].

OBJECTIVE: To investigate the clinicopathological features and prognosis of patients with the malignant transformation of sinonasal inverted papilloma. METHODS: Thirty-two consecutive cases encountered between January 1991 and January 2008 were retrospectively reviewed. Survival rates and prognostic factors were calculated with SPSS 17.0 software using the Kaplan-Meier method and multivariate Cox model survival analysis. RESULTS: The malignancy accounted for 8.99% of all types of sinonasal inverted papilloma. There were 25 males and 7 females, the median age was 56.5 years. The sites of tumor included 22 cases in nasal cavity and ethmoid sinuses, 10 cases in maxillary sinuses. The tumors included 21 high grade tumors, 8 intermediate grade tumors and 3 low grade tumors. Thirty-two patients were staged as T1(3/32), T2(10/32), T3(16/32), T4(3/32). According to the percentage of the malignant cell in the entire tumor tissue, 5 patients were in grade I, 5 patients were in grade II, 8 patients were in grade III, 14 patients were in grade IV. There were 3 distant metastasis in 32 patients; 19 patients underwent surgery plus postoperative radiotherapy, 10 underwent surgery alone and 3 underwent radiotherapy alone. The 5-year overall survival were 72.5%, and the median overall survival time was 62.2 months. Kaplan-Meier univariate survival analysis indicated that the clinical stages and treatment modalities were prognostic factors, and multivariate Cox model survival analysis confirmed that the clinical stages and treatment modalities were independent factors for overall survival (HR were 4.211 and 0.312, all P < 0.05). CONCLUSIONS: The morbidity of sinonasal inverted papilloma-associated malignancy is low, the clinical features were not specificity. The clinical stages and treatment modalities may affect the prognosis. Surgery plus postoperative radiotherapy are main treatment means.