Weizhen Liu

Clinicopathological and Prognostic Analysis of Primary Gastrointestinal Stromal Tumor Presenting with Gastrointestinal Bleeding: a 10-Year Retrospective Study

ObjectivesThe objectives of this paper were to investigate the clinicopathological characteristics and prognostic factors of GI-bleeding GIST patients and explore whether GI bleeding is a risk factor for GIST relapse.MethodsPrimary GIST patients with initial symptoms of GI bleeding or no GI bleeding were retrospectively studied.ResultsUp to 178 GI-bleeding GIST patients including 108 (60.7%) males and 70 (39.3%) females were evaluated for the clinicopathological characteristics. The stomach, small bowel, and colorectum were the tumor sites in 82 (46.1%), 85 (47.8%), and 11 (6.2%) patients. Of the 178 patients, 163 GI-bleeding patients had follow-up while another 363 patients from the total population presented without GI bleeding were followed up. Up to 526 patients who received postoperative follow-up were included in the survival analysis. Compared with the 363 non-GI-bleeding patients, GI-bleeding patients developed smaller tumors (P = 0.015) and had a longer relapse-free survival (RFS; P = 0.014). For the 163 GI-bleeding patients, a Cox regression analysis showed that the mitotic count and the platelet-lymphocyte ratio before surgery were independent prognostic predictors for poor outcome regarding RFS. For all 526 patients, a Cox regression analysis indicated that tumor location, mitotic index, platelet-lymphocyte ratio, and GI bleeding were independent prognosis predictors.ConclusionCompared to non-GI-bleeding GIST patients, patients with GI bleeding were more likely to be male and to have more small intestine GISTs, smaller tumors, and a longer RFS. For GI-bleeding patients, mitotic count and platelet-lymphocyte ratio were independent prognostic indicators. GI bleeding served as a surrogate for smaller GIST and was a protective factor for GIST recurrence.

Targeting CDK1 and MEK/ERK Overcomes Apoptotic Resistance in BRAF-Mutant Human Colorectal Cancer

The BRAFV600E mutation occurs in approximately 8% of human colorectal cancers and is associated with therapeutic resistance that is due, in part, to reactivation of MEK/ERK signaling cascade. Recently, pathway analysis identified cyclin-dependent kinase 1 (CDK1) upregulation in a subset of human BRAFV600E colorectal cancers. Therefore, it was determined whether CDK1 antagonism enhances the efficacy of MEK inhibition in BRAFV600E colorectal cancer cells. BRAFV600E colorectal cancer cell lines expressing CDK1 were sensitized to apoptosis upon siRNA knockdown or small-molecule inhibition with RO-3306 (CDK1 inhibitor) or dinaciclib (CDK1, 2, 5, 9 inhibitors). Combination of RO-3306 or dinaciclib with cobimetinib (MEK inhibitor) cooperatively enhanced apoptosis and reduced clonogenic survival versus monotherapy. Cells isogenic or ectopic for BRAFV600E displayed resistance to CDK1 inhibitors, as did cells with ectopic expression of constitutively active MEK. CDK1 inhibitors induced a CASP8-dependent apoptosis shown by caspase-8 restoration in deficient NB7 cells that enhanced dinaciclib-induced CASP3 cleavage. CDK inhibitors suppressed pro-CASP8 phosphorylation at S387, as shown by drug withdrawal, which restored p-S387 and increased mitosis. In a colorectal cancer xenograft model, dinaciclib plus cobimetinib produced significantly greater tumor growth inhibition in association with a caspase-dependent apoptosis versus either drug alone. The Cancer Genome Atlas (TCGA) transcriptomic dataset revealed overexpression of CDK1 in human colorectal cancers versus normal colon. Together, these data establish CDK1 as a novel mediator of apoptosis resistance in BRAFV600E colorectal cancers whose combined targeting with a MEK/ERK inhibitor represents an effective therapeutic strategy. Implications: CDK1 is a novel mediator of apoptosis resistance in BRAFV600E colorectal cancers whose dual targeting with a MEK inhibitor may be therapeutically effective. Mol Cancer Res; 16(3); 378–89. ©2017 AACR.

Wee1 inhibition can suppress tumor proliferation and sensitize p53 mutant colonic cancer cells to the anticancer effect of irinotecan

Wee1 is an oncogenic nuclear kinase, which can regulate the cell cycle as a crucial G2M checkpoint. Overexpression of Wee1 can be observed in various cancer types, which may lead to a poor prognosis, but the potential therapeutic value of Wee1 in colorectal cancer has not been fully studied. In the present study, the role of Wee1 in colonic cancer was investigated. Wee1 inhibition by small interfering RNA was demonstrated to significantly restrain cancer cell proliferation and sensitize the p53 mutant colonic cancer cell lines HT29 and SW480 to the effect of treatment with ionizing radiation. The anticancer effect of the Wee1 inhibitor MK1775 was investigated in these two colonic cancer cell lines. MK1775 was demonstrated to induce significant DNA damage, suppress cell viability and induce apoptosis. In addition, MK1775 sensitized HT29 and SW480 cells to the effect of irinotecan. Annexin V/propidium iodide staining demonstrated that combination therapy can induce increased apoptosis compared with MK1775 or irinotecan monotherapy. The results of western blot analysis also indicated increased expression of the DNA damage marker histone H2AX, and apoptosis‑associated protein cleaved caspase 3, in HT29 and SW480 cells. In conclusion, the present study indicated that Wee1 may be a valuable target for treatment of p53 mutant colonic cancer.

Clinicopathologic study of succinate-dehydrogenase-deficient gastrointestinal stromal tumors: A single-institutional experience in China

Abstract Gastrointestinal stromal tumors (GISTs) that are not driven by kinase mutations, as are most GISTs, often show loss of function of the succinate dehydrogenase (SDH) complex and are considered SDH-deficient GISTs. SDH-deficient GISTs share many distinct characteristics compared with conventional GISTs. However, data regarding these characteristics, particularly among Asian people, are relatively limited. The objective of this study was to characterize the clinicopathologic characteristics, treatment, and prognosis of these uncommon GISTs. This retrospective observational study enrolled 12 patients with SDH-deficient GISTs, who were selected from 335 patients with GIST diagnosed at our institution between October 31, 2013 and October 31, 2016 by succinate dehydrogenase subunit B staining. There were 8 male and 4 female patients, with a median age of 57 years (range, 21–73 years). Ten patients (83.3%) were diagnosed at or after the age of 40 years and represented 7.2% (10/138) of the entire population of elderly patients with gastric GISTs. The tumor size ranged from 3 to 19 cm (median, 7 cm); the primary tumor was multifocal in 6 cases (50%), and tumors had a multinodular or plexiform architecture in 10 cases (83.3%). Ten cases (83.3%) showed pure epithelioid morphology, with the remaining 2 cases (16.7%) showing mixed histologic subtype. Lymph node metastasis was found at the time of primary resection in 50% (3/6) of patients. Four cases (33.3%) had distant metastasis at presentation. Four patients (33.3%) developed disease progression during imatinib treatment after initial resection, but all of these patients regained disease control when the treatment was altered to sunitinib targeted therapy. SDH-deficient GISTs arise exclusively in the stomach and account for approximately 7.4% (12/162) of gastric GISTs. Moreover, those affecting people older than 40 years are not uncommon and sunitinib may work well for cases showing treatment failure with imatinib.

Clinicopathological features and prognosis of intestinal hepatoid adenocarcinoma: evaluation of a pooled case series

Backgroud Intestinal hepatoid adenocarcinoma (IHA) is a very rare and unique intestinal malignancy. Due to the lack of case series specifically pertaining to IHA, the clinicopathological features and prognosis of it remain unclear. Results Of the 42 patients enrolled in this study, 30 (71.4%) were male. Twenty-one cases (50.0%) were located in the colon. Eight cases (19.0%) had accompanying inflammatory bowel disease (IBD). Elevated serum alpha-fetoprotein (AFP) was detected for most patients (25/33, 84.8%). Twenty-five (59.5%) patients received complete resections. Vascular invasion (22/36, 61.1%), lymph node metastasis (28/36, 77.8%) and distant metastasis (21/42, 50.0%) were common. The 1-year progression-free survival (PFS) and disease-specific survival (DSS) of IHA were 26.9% and 30.6%, respectively. Multivariate analysis showed that only pTNM stage was an independent risk factor for PFS and DSS. PFS and DSS in patients with IHA were significantly lower than those with colorectal adenocarcinoma (CA) and hepatoid adenocarcinoma of the stomach (HAS). Conclusions IHA most commonly occurred in the colon and accompanied by IBD in several cases. pTNM stage was an independent factor for prognosis. The prognosis of IHA was significantly worse than that of CA and HAS. Patients and Methods Clinical data of IHA from four patients managed at our institution between January 2010 and December 2016, and 38 cases from research databases prior to 2017 were retrospectively studied.

Gli family zinc finger 1 is associated with endothelin receptor type B in Hirschsprung disease

Hirschsprung disease (HSCR) is a newborn colorectal disease characterized by an absence of ganglia in the distal gut. Hedgehog (Hh) and endothelin signaling serve important roles in gastrointestinal tract formation. Alterations in the signaling pathways disrupt the development of enteric neural crest cells (ENCCs). It is not known whether there is any coordination between these pathways in the pathogenesis of HSCR. In the present study, tissue samples from 35 patients with HSCR, including stenotic aganglionosis gut and normal ganglionic gut, were obtained. The expression of Gli family zinc finger 1 (Gli1) and endothelin receptor type B (EDNRB) was determined using reverse transcription-quantitative polymerase chain reaction, immunohistochemistry and western blotting. In addition, the SK-N-SH cell line was used to investigate the association between Hh signaling and the expression of EDNRB. The results revealed aberrant expression of Gli1 in the aganglionic segments, as well as decreased expression of Gli1 in tissues from 7 patients with HSCR exhibited, whereas tissues from 9 patients with HSCR exhibited increased Gli1 expression compared with the expression in the normal tissues. There was a negative association between EDNRB expression and Gli1 expression in the same sample. Knockdown of Gli1 by small interfering RNA and inhibition of Hh signaling by Vismodegib in SK-N-SH cells increased EDNRB expression. By contrast, upregulation of Gli1 expression by plasmids and activation of Hh signaling by Purmorphamine decreased EDNRB expression. Furthermore, premature enteric ganglia were observed in 4 patients with HSCR with decreased Gli1 expression. Thus, the results of the present study suggest that altered Gli1 expression negatively regulates EDNRB expression in patients with HSCR. The increased expression of EDNRB induced by decreased Gli1 expression may represent a novel mechanism in HSCR.