Yi-Ming Shyr

Signet-ring cell carcinoma (SRC) in advanced gastric cancer (GC) is often associated with more invasiveness and a worse prognosis than other cell types. The genetic alterations associated with gastric carcinogenesis in SRC are still unclear. In this study, 441 GC patients receiving curative surgery for GC between 2005 and 2013 were enrolled. The clinicopathological characteristics and genetic alterations of GC patients with and without SRC were compared. Among the 441 GC patients, 181 had SRC. For early GC, patients with SRC had more tumors located in the middle and lower stomach, more infiltrating tumors and better overall survival (OS) rates than those without SRC. For advanced GC, patients with SRC had more scirrhous type tumors, more PIK3CA amplifications, fewer microsatellite instability-high (MSI-H) tumors, more peritoneal recurrences and worse 5-year OS rates than those without SRC. For advanced GC with SRC, patients with peritoneal recurrence tended to have PD-L1 expression. For advanced GC without SRC, patients with liver metastasis tended to have PD-L1 expression, PI3K/AKT pathway mutations, TP53 mutations and MSI-H tumors. For advanced GC, PD-L1 expression was associated with peritoneal recurrence in SRC tumors, while non-SRC tumors with liver metastasis were likely to have PI3K/AKT pathway mutations, TP53 mutations and PD-L1 expression; immunotherapy and targeted therapy may be beneficial for these patients.

Background: Epstein–Barr virus (EBV)-associated gastric cancer (GC) is one of four major gastric cancer types and is traditionally considered to be related to lymphoepithelioma-like GC. Few studies have investigated the clinical significance of EBV infection in intestinal/solid type, diffuse (poorly cohesive) type, and lymphoepithelioma-like GC. Methods: A total of 460 GC patients receiving curative surgery were enrolled. The clinicopathological features, genetic alterations and prognoses were compared between patients with and without EBV infection. Results: EBV-positive GC patients (n = 43) had more tumors located in the upper and middle stomach, more common in lymphoepithelioma-like carcinoma, more lymphoid stroma, fewer Helicobacter pylori infections, and higher programmed death-ligand 1 (PD-L1) expression than EBV-negative GC patients. For intestinal/solid type GC, EBV-positive tumors were more likely to be located in the upper and middle stomach, have more lymphoid stroma, fewer Helicobacter pylori infections, higher PD-L1 expression, and more liver metastases than EBV-negative tumors. For diffuse (poorly cohesive) type GC, EBV-positive tumors were more likely to be located in the upper stomach, and have more lymphoid stroma than EBV-negative tumors. For lymphoepithelioma-like GC, EBV-positive tumors had more PI3K/AKT pathway mutations than EBV-negative tumors. Conclusions: Intestinal/solid type GC patients with EBV-positive tumors were associated with higher PD-L1 expression and more liver metastases, while lymphoepithelioma-like GC patients with EBV-positive tumors had more PI3K/AKT pathway mutations. Immunotherapy and targeted therapy may be beneficial for these groups of patients. Routine EBV survey is recommended in GC.

Background: There has been no report regarding the clinicopathological features and genetic mutations regarding elevated microsatellite alterations at selected tetranucleotide repeats (EMAST) in gastric cancer (GC). Methods: The correlation among EMAST status, microsatellite instability (MSI) status, mutations of common GC-related genes and 16 DNA repair-associated genes, and the clinicopathological features were analyzed. Results: Among the 360 GC patients enrolled, there were 76 (21.1%) with EMAST+ tumors and 284 with EMAST− tumors, and 59 (16.4%) were MSI-high (MSI-H) tumors, and 301 were microsatellite stable (MSS) tumors. Patients with EMAST+ tumors exhibited an earlier pathological T category and had more genetic mutations in the PI3K/AKT pathway, ARID1A and DNA repair-associated genes than those with EMAST− tumors. Patients with MSI-H tumors have more genetic mutations in the PI3K/AKT pathway and DNA repair-associated genes than those with MSS tumors. In the subgroup analysis for MSI-H GC, EMAST+ tumors were associated with earlier pathological T and N categories, earlier TNM stages, higher frequency of DNA-repair-associated genetic mutations, and a better survival rate than EMAST− tumors. Conclusions: PI3K/AKT pathway mutations may play an important role in EMAST+ and/or MSI-H GC. EMAST+/MSI-H tumors seem to represent a different subtype of gastric cancer from EMAST−/MSI-H tumors.

Our previous study demonstrated that an up-regulation of the Brain-Derived Neurotrophic Factor (BDNF) signaling pathway is involved the mechanism causing the recurrence of triple negative breast cancer. The aim of this study is to investigate the effects of commonly used Chinese medicinal herbs on MDA-MB-231 and HUVEC cells and how they interact with BDNF. Human TNBC MDA-MB-231 cells and human endothelial HUVEC cells were used to explore the effect of commonly used Chinese herbal medicines on cancer cells alone, on endothelial cells alone and on cancer cell/endothelial cell interactions; this was done via functional studies, including migration and invasion assays. Furthermore, Western blot analysis and real-time PCR investigations were also used to investigate migration signal transduction, invasion signal transduction, and angiogenic signal transduction in these systems. Finally, the effect of the Chinese medicinal herbs on cancer cell/endothelial cell interactions was assessed using co-culture and ELISA. In terms of autoregulation, BDNF up-regulated TrkB gene expression in both MDA-MB-231 and HUVEC cells. Furthermore, BDNF enhanced migration by MDA-MB-231 cells via Rac, Cdc42 and MMP, while also increasing the migration of HUVEC cells via MMP and COX-2 expression. As measured by ELISA, the Chinese herbal medicinal herbs A. membranaceus, P. lactiflora, L. chuanxiong, P. suffruticosa and L. lucidum increased BDNF secretion by MDA-MB-231 cells. Similarly, using a co-culture system with MDA-MB-231 cells, A. membranaceus and L. lucidum modulated BDNF-TrkB signaling by HUVEC cells. We conclude that BDNF plays an important role in the metastatic interaction between MDA-MB-231 and HUVEC cells. Some Chinese medicinal herbs are able to enhance the BDNF-related metastatic potential of the interaction between cancer cells and endothelial cells. These findings provide important information that should help with the development of integrated medical therapies for breast cancer patients.

As life expectancy continues to increase around the world, the use of minimally invasive surgery (MIS) could be beneficial for octogenarian and older gastric cancer patients. A total of 359 gastric cancer patients who underwent curative surgery between March 2011 and March 2015 were enrolled; 80 of these patients (22.2%) were octogenarians and older. Surgical approaches included MIS (50 laparoscopic and 65 robotic) and open surgery (n = 244). Surgical outcomes of MIS and open surgery in octogenarian and older patients were compared with younger patients. Among octogenarian and older patients, relative to open surgery (n = 53), MIS (n = 27) was associated with less operative blood loss, a shorter postoperative hospital stay and similar rates of surgical complications and mortality. For MIS (n = 115), octogenarian and older patients exhibited similar postoperative outcomes to those of younger patients. For open surgery (n = 244), relative to younger patients, octogenarian and older patients experienced longer postoperative hospital stays, a higher rate of wound infection and a higher incidence of pneumonia. MIS for gastric cancer is beneficial and can be performed safely in octogenarian and older patients.

Evidence shows that Luminal A breast cancer is likely to undergo bone metastasis, but the mechanisms involved remain unknown. This study’s aim was to demonstrate a correlation between estrogen receptor (ER) positivity and bone metastasis as the clinically preferred site of metastasis, as well as investigating the role of ERα-Src signaling in MCF-7 cells using Snail over-expression as an in vivo bone metastasis model. Clinically, the records of breast cancer with distant metastasis were retrospectively reviewed to correlate breast cancer subtypes and preferential metastatic sites. An in vivo bone metastasis model was created by injection of MCF-7 cells with/without Snail over-expression into the tibia of nude mice. The human MCF-7 cells that over-expressed (o/e) Snail were examined and the expression of epithelial–mesenchymal transitions (EMT) markers, ER-Src signaling proteins and p190 RhoGAP analyzed by Western blotting and real-time PCR. The role of ERα was elucidated using ESR1 silence by transfecting shRNA (∆ESR1) into MCF-7 o/e Snail cells in vitro and in vivo. The clinical results showed that ER ≥1% breast cancers showed a positive correlation with bone metastasis, which was found to be the preferred site of metastasis. An in vivo bone metastasis was successfully established using injection of MCF-7 o/e Snail cells into the tibia of nude mice, but no such metastasis was found using control MCF-7 cells. The proteins expressed in MCF-7 o/e Snail cells showed an EMT pattern, while those of the MCF-7 o/e Snail metastatic tissue showed a mesenchymal–epithelial pattern. There was an increase in cytosolic Src, p190 RhoGAP and nuclear ERα proteins, but not in Snail, in MCF-7 o/e Snail tissue compared to the same cell line in vitro. ESR1 knock down decreased Src and p190 RhoGAP expression in vitro and also decreased the incidence of bone metastasis in vivo. We conclude that ER-Src signaling plays an important role in ER (+) breast cancer, which shows a high potential for bone metastasis.

Background “Precision medicine” is a concept that by utilizing modern molecular diagnostics, an effective therapy is accurately applied for each cancer patient to improve their survival rates. The treatment of triple-negative breast cancer (TNBC) remains a challenging issue. The aim of this study was to compare the molecular subtypes of triple-negative breast cancer (TNBC) between Taiwanese and Non-Asian women. Methods GEO Datasets for non-Asian (12 groups, n = 1450) and Taiwanese (3 groups, n = 465) breast cancer, including 617 TNBC, were acquired, normalized and cluster analyzed. Then, using TNBC cell lines of different subtypes, namely, MDA-MB-468 (basal-like1, BL1), MDA-MB-231 (mesenchymal stem like, MSL), BT-549 (mesenchymal, M), MDA-MB-453 (luminal androgen receptor, LAR), and DU4475 (immunomodulatory, IM), real-time PCR in triplicate for 47 genes signatures were performed to validate the specificity of these subtypes. Results The results showed that the percentage of TNBC subtypes in non-Asian women, namely, BL1, BL2, IM, M, MSL, and LAR was 13.56, 8.91, 16.80, 20.45, 8.30, and 11.13%, respectively. When data from Taiwanese were normalized and clustered, five TNBC subtypes, namely, BL (8.94%), IM (13.82%), M (22.76%), MSL (30.89%), and LAR (23.58%), were classified. Real-time PCR validated the specificity of these subtypes. Besides, the presence of interaction between IM- and MSL-subtypes suggests the involvement of tumor microenvironment in TNBC subtype classification. Conclusion Our data suggested that there exist different presentations between non-Asian and Taiwanese TNBC subtypes, which provides important information when selection of therapeutic targets or designs for clinical trials for TNBC patients.

With the progression of molecular techniques, the detection of circulating plasma DNA (cpDNA) is clinically feasible. However, the role of the cpDNA levels in gastric cancer is not well understood. This study assessed the mutational profile in primary tumors and clarified the clinical utility of quantitative and qualitative cpDNA alterations in 277 patients with advanced gastric cancer. The concentrations of cpDNA were measured by TaqMan qPCR, and 68 mutations in 8 genes were studied for cpDNA mutations. The median cpDNA concentrations in patients with stages I, II, and III gastric cancer were 3979, 3390 and 4278 copies/mL, respectively, and increased to 11,380 copies/mL in patients with Stage IV gastric cancer (p < 0.001). Among the 35 patients harboring cpDNA mutations, Stage IV patients (100%) were more likely to display high cpDNA levels than were Stage I (33.3%), II (75%) and III patients (66.7%) (p = 0.037). Patients displaying high cpDNA levels were more likely to experience peritoneal recurrence and exhibited significantly lower 5‐year overall survival rates (39.2% vs. 45.8%, p = 0.039) than did patients displaying low cpDNA levels. Only for late stage (Stages III or IV) gastric cancer, patients harboring cpDNA mutations were more likely to experience vascular invasion (20% vs. 2.4%, p = 0.036) and exhibited a lower 5‐year overall survival rate than did those lacking cpDNA mutations (5.6% vs. 31.5%, p = 0.028). High cpDNA levels are associated with peritoneal recurrence and poor prognosis in patients with advanced gastric cancer; harboring cpDNA mutations is associated with poor prognosis among patients with late stage gastric cancer.

Mutations in PI3K/AKT pathway genes and amplifications of PIK3CA are associated with patterns of recurrence in gastric cancers