The Nef protein of HIV-1 downregulates the cell surface co-receptor CD4 by hijacking the clathrin adaptor complex AP-2. The structural basis for the hijacking of AP-2 by Nef is revealed by a 2.9 Å crystal structure of Nef bound to the α and σ2 subunits of AP-2. Nef binds to AP-2 via its central loop (residues 149-179) and its core. The determinants for Nef binding include residues that directly contact AP-2 and others that stabilize the binding-competent conformation of the central loop. Residues involved in both direct and indirect interactions are required for the binding of Nef to AP-2 and for downregulation of CD4. These results lead to a model for the docking of the full AP-2 tetramer to membranes as bound to Nef, such that the cytosolic tail of CD4 is situated to interact with its binding site on Nef. DOI: http://dx.doi.org/10.7554/eLife.01754.001.

Purpose

To evaluate the incidence of colon cancer as a second primary cancer (CCSPC) and the survival outcomes of women with and without CCSPC after the diagnosis of endometrial cancer (EC).

Methods

The standardized incidence ratio (SIR) of CCSPC and survival outcomes of EC survivors with and without CCSPC were analyzed using data from January 1 1993 to December 31 2011, obtained from the Korea Central Cancer Registry.

Results

Of 14,797 EC survivors, 147 (0.99%) developed CCSPC after an average interval of 5.5 years. The SIR of CCSPC among EC survivors was 2.56, higher than that of colon cancer in the general population. The SIR of CCSPC was highest for the ascending (3.77), followed by the transverse (3.45), descending colon (2.06), and rectum (1.99). The risk of a proximal site of CCSPC was high, especially within 5 years after the diagnosis of EC in the ascending (SIR, 4.37) and transverse (4.91) colon, and in young survivors (< 60 years) in the ascending (5.19) and transverse (3.82) colon. The 5- and 10-year overall survival rates were 84.8 and 80.4% among survivors with EC only and 89.2 and 76.3% for survivors with CCSPC, respectively.

Conclusions

The risk of CCSPC among EC survivors increases especially in the proximal colon in young survivors. These results could be used for surveillance and counseling of EC survivors.

BACKGROUND: Secondary surgical cytoreduction in women with platinum-sensitive, recurrent epithelial ovarian, primary peritoneal, or fallopian-tube (ovarian) cancer is widely practiced but has not been evaluated in phase 3 investigation. METHODS: We randomly assigned patients with recurrent ovarian cancer who had received one previous therapy, had an interval during which no platinum-based chemotherapy was used (platinum-free interval) of 6 months or more, and had investigator-determined resectable disease (to no macroscopic residual disease) to undergo secondary surgical cytoreduction and then receive platinum-based chemotherapy or to receive platinum-based chemotherapy alone. Adjuvant chemotherapy (paclitaxel-carboplatin or gemcitabine-carboplatin) and use of bevacizumab were at the discretion of the investigator. The primary end point was overall survival. RESULTS: A total of 485 patients underwent randomization, 240 to secondary cytoreduction before chemotherapy and 245 to chemotherapy alone. The median follow-up was 48.1 months. Complete gross resection was achieved in 67% of the patients assigned to surgery who underwent the procedure. Platinum-based chemotherapy with bevacizumab followed by bevacizumab maintenance was administered to 84% of the patients overall and was equally distributed between the two groups. The hazard ratio for death (surgery vs. no surgery) was 1.29 (95% confidence interval [CI], 0.97 to 1.72; P = 0.08), which corresponded to a median overall survival of 50.6 months and 64.7 months, respectively. Adjustment for platinum-free interval and chemotherapy choice did not alter the effect. The hazard ratio for disease progression or death (surgery vs. no surgery) was 0.82 (95% CI, 0.66 to 1.01; median progression-free survival, 18.9 months and 16.2 months, respectively). Surgical morbidity at 30 days was 9%; 1 patient (0.4%) died from postoperative complications. Patient-reported quality of life decreased significantly after surgery but did not differ significantly between the two groups after recovery. CONCLUSIONS: In this trial involving patients with platinum-sensitive, recurrent ovarian cancer, secondary surgical cytoreduction followed by chemotherapy did not result in longer overall survival than chemotherapy alone. (Funded by the National Cancer Institute and others; GOG-0213 ClinicalTrials.gov number, NCT00565851.).

Background

Secondary surgical cytoreduction in women with platinum-sensitive, recurrent epithelial ovarian, primary peritoneal, or fallopian-tube ("ovarian") cancer is widely practiced but has not been evaluated in phase 3 investigation.

Methods

We randomly assigned patients with recurrent ovarian cancer who had received one previous therapy, had an interval during which no platinum-based chemotherapy was used (platinum-free interval) of 6 months or more, and had investigator-determined resectable disease (to no macroscopic residual disease) to undergo secondary surgical cytoreduction and then receive platinum-based chemotherapy or to receive platinum-based chemotherapy alone. Adjuvant chemotherapy (paclitaxel-carboplatin or gemcitabine-carboplatin) and use of bevacizumab were at the discretion of the investigator. The primary end point was overall survival.

Results

A total of 485 patients underwent randomization, 240 to secondary cytoreduction before chemotherapy and 245 to chemotherapy alone. The median follow-up was 48.1 months. Complete gross resection was achieved in 67% of the patients assigned to surgery who underwent the procedure. Platinum-based chemotherapy with bevacizumab followed by bevacizumab maintenance was administered to 84% of the patients overall and was equally distributed between the two groups. The hazard ratio for death (surgery vs. no surgery) was 1.29 (95% confidence interval [CI], 0.97 to 1.72; P = 0.08), which corresponded to a median overall survival of 50.6 months and 64.7 months, respectively. Adjustment for platinum-free interval and chemotherapy choice did not alter the effect. The hazard ratio for disease progression or death (surgery vs. no surgery) was 0.82 (95% CI, 0.66 to 1.01; median progression-free survival, 18.9 months and 16.2 months, respectively). Surgical morbidity at 30 days was 9%; 1 patient (0.4%) died from postoperative complications. Patient-reported quality of life decreased significantly after surgery but did not differ significantly between the two groups after recovery.

Conclusions

In this trial involving patients with platinum-sensitive, recurrent ovarian cancer, secondary surgical cytoreduction followed by chemotherapy did not result in longer overall survival than chemotherapy alone. (Funded by the National Cancer Institute and others; GOG-0213 ClinicalTrials.gov number, NCT00565851.).

Purpose

Advanced-stage mucinous ovarian carcinoma (MOC) has poor chemotherapy response and prognosis and lacks biomarkers to aid stage I adjuvant treatment. Differentiating primary MOC from gastrointestinal (GI) metastases to the ovary is also challenging due to phenotypic similarities. Clinicopathologic and gene-expression data were analyzed to identify prognostic and diagnostic features.

Experimental design

Discovery analyses selected 19 genes with prognostic/diagnostic potential. Validation was performed through the Ovarian Tumor Tissue Analysis consortium and GI cancer biobanks comprising 604 patients with MOC (n = 333), mucinous borderline ovarian tumors (MBOT, n = 151), and upper GI (n = 65) and lower GI tumors (n = 55).

Results

Infiltrative pattern of invasion was associated with decreased overall survival (OS) within 2 years from diagnosis, compared with expansile pattern in stage I MOC [hazard ratio (HR), 2.77; 95% confidence interval (CI), 1.04-7.41, P = 0.042]. Increased expression of THBS2 and TAGLN was associated with shorter OS in MOC patients (HR, 1.25; 95% CI, 1.04-1.51, P = 0.016) and (HR, 1.21; 95% CI, 1.01-1.45, P = 0.043), respectively. ERBB2 (HER2) amplification or high mRNA expression was evident in 64 of 243 (26%) of MOCs, but only 8 of 243 (3%) were also infiltrative (4/39, 10%) or stage III/IV (4/31, 13%).

Conclusions

An infiltrative growth pattern infers poor prognosis within 2 years from diagnosis and may help select stage I patients for adjuvant therapy. High expression of THBS2 and TAGLN in MOC confers an adverse prognosis and is upregulated in the infiltrative subtype, which warrants further investigation. Anti-HER2 therapy should be investigated in a subset of patients. MOC samples clustered with upper GI, yet markers to differentiate these entities remain elusive, suggesting similar underlying biology and shared treatment strategies.