Choline Kinase α Mediates Interactions Between the Epidermal Growth Factor Receptor and Mechanistic Target of Rapamycin Complex 2 in Hepatocellular Carcinoma Cells to Promote Drug Resistance and Xenograft Tumor Progression.

BACKGROUND & AIMS: Choline kinase α (CHKA) catalyzes conversion of choline to phosphocholine and can contribute to carcinogenesis. Little is known about the role of CHKA in the pathogenesis of hepatocellular carcinoma (HCC). METHODS: We performed whole-exome and transcriptome sequence analyses of 9 paired HCC and non-tumor-adjacent tissues. We performed tissue chip analyses of 120 primary HCC and non-tumor-adjacent tissues from patients who received surgery in Shanghai, China from January 2006 through December 2009; 48 sets of specimens (HCC and non-tumor-adjacent tissues) were also analyzed. CHKA gene copy number was quantified and findings were validated by quantitative reverse transcription polymerase chain reaction analysis. CHKA messenger RNA and protein levels were determined by polymerase chain reaction, immunohistochemical, and immunoblot analyses. CHKA was examined in 2 hepatocyte cell lines and 7 HCC-derived cell lines, and knocked down with small interfering RNAs in 3 HCC cell lines. Cells were analyzed in proliferation, wound healing, migration, and invasion assays. Cells were injected into tail veins of mice and tumor growth and metastasis were quantified. Immunoprecipitation and immunofluorescence assays were conducted to determine interactions between CHKA and the epidermal growth factor receptor (EGFR) and the mechanistic target of rapamycin complex 2. RESULTS: Levels of CHKA messenger RNA were frequently increased in HCC tissues compared with nontumor tissues; increased expression was associated with amplification at the CHKA loci. Tumors that expressed high levels of CHKA had more aggressive phenotypes, and patients with these tumors had shorter survival times after surgery compared to patients whose tumors expressed low levels of CHKA. HCC cell lines that stably overexpressed CHKA had higher levels of migration and invasion than control HCC cells, and formed larger xenograft tumors with more metastases in mice compared to HCC cells that did not overexpress CHKA. CHKA was required for physical interaction between EGFR and mechanistic target of rapamycin complex 2. This complex was required for HCC cells to form metastatic xenograft tumors in mice and to become resistant to EGFR inhibitors. CONCLUSIONS: We found levels of CHKA to be increased in human HCCs compared to nontumor tissues, and increased expression to be associated with tumor aggressiveness and reduced survival times of patients. Overexpression of CHKA in HCC cell lines increased their invasiveness, resistance to EGFR inhibitors, and ability to form metastatic tumors in mice by promoting interaction of EGFR with mechanistic target of rapamycin complex 2.

The prognostic importance of jaundice in surgical resection with curative intent for gallbladder cancer.

BACKGROUND: Preoperative jaundice is frequent in gallbladder cancer (GBC) and indicates advanced disease. Resection is rarely recommended to treat advanced GBC. An aggressive surgical approach for advanced GBC remains lacking because of the association of this disease with serious postoperative complications and poor prognosis. This study aims to re-assess the prognostic value of jaundice for the morbidity, mortality, and survival of GBC patients who underwent surgical resection with curative intent. METHODS: GBC patients who underwent surgical resection with curative intent at a single institution between January 2003 and December 2012 were identified from a prospectively maintained database. RESULTS: A total of 192 patients underwent surgical resection with curative intent, of whom 47 had preoperative jaundice and 145 had none. Compared with the non-jaundiced patients, the jaundiced patients had significantly longer operative time (p < 0.001) and more intra-operative bleeding (p = 0.001), frequent combined resections of adjacent organs (23.4% vs. 2.8%, p = 0.001), and postoperative complications (12.4% vs. 34%, p = 0.001). Multivariate analysis showed that preoperative jaundice was the only independent predictor of postoperative complications. The jaundiced patients had lower survival rates than the non-jaundiced patients (p < 0.001). However, lymph node metastasis and gallbladder neck tumors were the only significant risk factors of poor prognosis. Non-curative resection was the only independent predictor of poor prognosis among the jaundiced patients. The survival rates of the jaundiced patients with preoperative biliary drainage (PBD) were similar to those of the jaundiced patients without PBD (p = 0.968). No significant differences in the rate of postoperative intra-abdominal abscesses were found between the jaundiced patients with and without PBD (n = 4, 21.1% vs. n = 5, 17.9%, p = 0.787). CONCLUSIONS: Preoperative jaundice indicates poor prognosis and high postoperative morbidity but is not a surgical contraindication. Gallbladder neck tumors significantly increase the surgical difficulty and reduce the opportunities for radical resection. Gallbladder neck tumors can independently predict poor outcome. PBD correlates with neither a low rate of postoperative intra-abdominal abscesses nor a high survival rate.

The outcome of ipsilateral hemihepatectomy in mucin-producing bile duct tumors.

BACKGROUND: Mucin-producing bile duct tumors (MPBTs) are unusual, and we present our experience with nine surgically proven cases. METHODS: Between November 2002 and November 2012, 9 patients with surgically proven MPBTs (including history of relevant hepatobiliary surgery in 6 patients) were encountered. Their clinical, imaging, and surgical findings were reviewed. RESULTS: The most common symptom is intermittent jaundice, which occurs in seven patients. The diagnostic specificity was 77.8% by preoperative Magnetic Resonance Cholangiopancreatography (MRCP). All the patients underwent ipsilateral hemihepatectomy or remnant hemihepatectomy, accompanied caudate lobectomy in one case and concomitant Roux-en-Y choledochojejunostomy in four cases. Postoperative course was uneventful. One patient, who had intra-abdominal recurrence 59 months after surgery, was received reoperation without recurrence at the last follow-up. The remaining eight patients were alive without disease recurrence. CONCLUSION: Based on our follow up of 9 cases that were surgically treated for MPBTs, we conclude that ipsilateral hemihepatectomy is a safe surgical procedure with an observed recurrence risk of 11.1% and all long-term survival.