Pathological and Biological Significance of the Specific Glycan, TRA-1-60, on Aggressive Gastric Adenocarcinoma.

The glycans form a unique complex on the surface of cancer cells and play a pivotal role in tumor progression, impacting proliferation, invasion, and metastasis. TRA-1-60 is a glycan that was identified as a critical marker for the establishment of fully reprogrammed inducible pluripotent stem cells. Its expression has been detected in multiple cancer tissues, including embryonal carcinoma, prostate cancer, and pancreatic cancer, but the biological and pathological characterization of TRA-1-60-expressing tumor cells remains unclear within various types of malignancies. Here, we report the biological characteristics of TRA-1-60-expressing gastric cancer cells, especially those with its cell surface expression, and the therapeutic significance of targeting TRA-1-60. The cells with cell membrane expression of TRA-1-60 were mainly observed in the invasive area of patient gastric cancer tissues and correlated with advanced stages of the disease based on histopathological and clinicopathological analyses. In vitro analysis using a scirrhous gastric adenocarcinoma line, HSC-58, which highly expresses TRA-1-60 on its plasma membrane, revealed increased stress-resistant mechanisms, supported by the upregulation of glutathione synthetase and NCF-1 (p47phox) via lipid-ROS regulatory pathways, as detected by RNA-seq analysis followed by oxidative stress gene profiling. Our in vivo therapeutic study using the TRA-1-60-targeting antibody-drug conjugate, namely, Bstrongomab-conjugated monomethyl auristatin E, showed robust efficacy in a mouse model of peritoneal carcinomatosis induced by intraperitoneal xenograft of HSC-58, by markedly reducing massive tumor ascites. Thus, targeting the specific cell surface glycan, TRA-1-60, shows a significant therapeutic impact in advanced-stage gastric cancers.

Mucin phenotype and genetic alterations in non-V600E BRAF-mutated colorectal cancer.

Colorectal cancer (CRC) is a heterogeneous disease that develops through stepwise accumulation of genetic alterations and progresses via several distinct pathways. However, the tumorigenesis of CRCs with BRAF non-V600E mutations remains unclear. Here, we aimed to elucidate the tumorigenesis of CRCs with BRAF non-V600E mutations, focusing on differences in mucin phenotype and genetic alterations between CRCs with non-V600E and V600E mutations. We investigated 201 patients with CRC and performed panel testing of 415 genes to identify BRAF mutations. Patients were classified into five mucin phenotypes - large-intestinal, small-intestinal, gastric, mixed, and unclassified - using immunohistochemistry for CD10, MUC2, MUC5AC, and MUC6. BRAF mutations were identified in 24 of 201 patients' samples, of which 13 (6.5%) had a V600E mutation (V600E-mutant) and 11 (5.5%) had non-V600E mutations (non-V600E-mutant). MUC5AC expression was significantly associated with V600E mutations (P = 0.040), while CD10 expression was significantly associated with non-V600E mutations (P = 0.010). The small-intestinal mucin phenotype was significantly associated with non-V600E mutations (P = 0.031), while the mixed mucin phenotype was significantly associated with V600E mutations (P = 0.027). Regarding genetic alterations, focusing on the WNT signaling pathway, APC mutation was significantly associated with non-V600E mutations (P < 0.001), while RNF43 mutation was significantly associated with V600E mutations (P = 0.020). Considering the differences in mucin phenotype and genetic alterations, different modes of tumorigenesis are assumed for CRC with BRAF V600E mutation and non-V600E mutations. These findings are important in understanding the biology and treatment strategies for BRAF-mutant CRC.

Recent trends and perspectives in reconstruction and regeneration of intra/extra-oral wounds using tissue-engineered oral mucosa equivalents.

Many conditions, including cancer, trauma, and congenital anomalies, can damage the oral mucosa. Multiple cultures of oral mucosal cells have been used for biocompatibility tests and oral biology studies. In recent decades, the clinical translation of tissue-engineered products has progressed significantly in developing tangible therapies and inspiring advancements in medical science. However, the reconstruction of an intraoral mucosa defect remains a significant challenge. Despite the drawbacks of donor-site morbidity and limited tissue supply, the use of autologous oral mucosa remains the gold standard for oral mucosa reconstruction and repair. Tissue engineering offers a promising solution for repairing and reconstructing oral mucosa tissues. Cell- and scaffold-based tissue engineering approaches have been employed to treat various soft tissue defects, suggesting the potential clinical use of tissue-engineered oral mucosa (TEOMs). In this review, we first cover the recent trends in the reconstruction and regeneration of extra-/intra-oral wounds using TEOMs. Next, we describe the current status and challenges of TEOMs. Finally, future strategic approaches and potential technologies to support the advancement of TEOMs for clinical use are discussed.

Clinical significance of metastatic tumor deposit foci in rectal cancer in the lateral pelvic lymph node area.

BACKGROUND: Although previous studies have demonstrated that tumor deposits (TDs) are associated with worse prognosis in colon cancer, their clinical significance in rectal cancer has not been fully elucidated, especially in the lateral pelvic lymph node (LPLN) area. This study aimed to clarify the clinical significance of TDs, focusing on the number of metastatic foci, including lymph node metastases (LNMs) and TDs, in the LPLN area. METHODS: This retrospective study involved 226 consecutive patients with cStage II/III low rectal cancer who underwent LPLN dissection. Metastatic foci, including LNM and TD, in the LPLN area were defined as lateral pelvic metastases (LP-M) and were evaluated according to LP-M status: presence (absence vs. presence), histopathological classification (LNM vs. TD), and number (one to three vs. four or more). We evaluated the relapse-free survival of each model and compared them using the Akaike information criterion (AIC) and Harrell's concordance index (c-index). RESULTS: Forty-nine of 226 patients (22%) had LP-M, and 15 patients (7%) had TDs. The median number of LP-M per patient was one (range, 1-9). The best risk stratification power was observed for number (AIC, 758; c-index, 0.668) compared with presence (AIC, 759; c-index, 0.665) and histopathological classification (AIC, 761; c-index, 0.664). The number of LP-M was an independent prognostic factor for both relapse-free and overall survival, and was significantly associated with cumulative local recurrence. CONCLUSION: The number of metastatic foci, including LNMs and TDs, in the LPLN area is useful for risk stratification of patients with low rectal cancer.

Copy number alteration is an independent prognostic biomarker in triple-negative breast cancer patients.

BACKGROUND: Next-generation sequencing (NGS) has enabled comprehensive genomic profiling to identify gene alterations that play important roles in cancer biology. However, the clinical significance of these genomic alterations in triple-negative breast cancer (TNBC) patients has not yet been fully elucidated. The aim of this study was to clarify the clinical significance of genomic profiling data, including copy number alterations (CNA) and tumor mutation burden (TMB), in TNBC patients. METHODS: A total of 47 patients with Stage I-III TNBC with genomic profiling of 435 known cancer genes by NGS were enrolled in this study. Disease-free survival (DFS) and overall survival (OS) were evaluated for their association to gene profiling data. RESULTS: CNA-high patients showed significantly worse DFS and OS than CNA-low patients (p = 0.0009, p = 0.0041, respectively). TMB was not associated with DFS or OS in TNBC patients. Patients with TP53 alterations showed a tendency of worse DFS (p = 0.0953) and significantly worse OS (p = 0.0338) compared with patients without TP53 alterations. Multivariable analysis including CNA and other clinicopathological parameters revealed that CNA was an independent prognostic factor for DFS (p = 0.0104) and OS (p = 0.0306). Finally, multivariable analysis also revealed the combination of CNA-high and TP53 alterations is an independent prognostic factor for DFS (p = 0.0005) and OS (p = 0.0023). CONCLUSIONS: We revealed that CNA, but not TMB, is significantly associated with DFS and OS in TNBC patients. The combination of CNA-high and TP53 alterations may be a promising biomarker that can inform beyond standard clinicopathologic factors to identify a subgroup of TNBC patients with significantly worse prognosis.

Gene panel testing detects important genetic alterations in ulcerative colitis-associated colorectal neoplasia.

Ulcerative colitis-associated neoplasia (UCAN) harbors unique genetic alterations and mutational tendencies. The clinical application of gene panel testing enables precision medicine by tailoring treatment to individual gene alterations. We hypothesized that gene panel testing may detect clinically important genetic alterations in UCAN, with potential usefulness for the diagnosis and treatment of UCAN. In the present study, gene panel testing was used to identify genetic alterations in UCAN, and the possibility of clinical utility of gene panel testing in UCAN was investigated. The present study included 15 patients with UCAN, and gene panel testing was performed to identify genetic alterations associated with diagnosis and treatment. Genetic alterations of UCAN were compared with those of 203 patients with sporadic colorectal cancer (CRC). APC and PTEN mutations were less frequent, while RNF43 frameshift or nonsense mutations were more frequent in UCAN compared with sporadic CRC. TP53 mutations were identified in 13/15 patients (87%) with UCAN. Notably, 4/15 patients (27%) with UCAN had no genetic alterations other than TP53 mutation, while this occurred in 1/203 patients (0.5%) with sporadic CRC (P<0.001). Microsatellite instability-high was identified in 2/15 patients (13%) with UCAN. Mutational signature 3, which is associated with homologous recombination deficiency, was detected in 14/15 patients (93%) with UCAN, and enriched in UCAN compared with sporadic CRC (P=0.030). In conclusion, gene panel testing can detect important genetic alterations that can be useful for diagnosis and treatment in UCAN, and may provide clinicians with important information for tailored treatment strategies.

NKp44-based chimeric antigen receptor effectively redirects primary T cells against synovial sarcoma.

BACKGROUND: T-cell receptor-engineered T-cell therapies have achieved promising response rates against synovial sarcoma in clinical trials, but their applicability is limited owing to the HLA matching requirement. Chimeric antigen receptor (CAR) can redirect primary T cells to tumor-associated antigens without requiring HLA matching. However, various obstacles, including the paucity of targetable antigens, must be addressed for synovial sarcoma. Ligands for natural killer (NK) cell-activating receptors are highly expressed by tumor cells. METHODS: The surface expression of ligands for NK cell-activating receptors in synovial sarcoma cell lines was analyzed. We analyzed RNA sequencing data deposited in a public database to evaluate NKp44-ligand expression. Primary T cells retrovirally transduced with CAR targeting NKp44 ligands were evaluated for their functions in synovial sarcoma cells. Alterations induced by various stimuli, including a histone deacetylase inhibitor, a hypomethylating agent, inflammatory cytokines, and ionizing radiation, in the expression levels of NKp44 ligands were investigated. RESULTS: Ligands for NKp44 and NKp30 were expressed in all cell lines. NKG2D ligands were barely expressed in a single cell line. None of the cell lines expressed NKp46 ligand. Primary synovial sarcoma cells expressed the mRNA of the truncated isoform of MLL5, a known cellular ligand for NKp44. NKp44-based CAR T cells specifically recognize synovial sarcoma cells, secrete interferon-γ, and exert suppressive effects on tumor cell growth. No stimulus altered the expression of NKp44 ligands. CONCLUSION: NKp44-based CAR T cells can redirect primary human T cells to synovial sarcoma cells. CAR-based cell therapies may be an option for treating synovial sarcomas.

Unveiling microbiome profiles in human inner body fluids and tumor tissues with pancreatic or biliary tract cancer.

With the discovery of bacterial symbiosis in the tissues of various cancers, the study of the tumor microbiome is attracting a great deal of attention. Anatomically, since the gastrointestinal tract, liver, and pancreas form a continuous ductal structure, the microbiomes in the digestive juices of these organs may influence each other. Here, we report a series of microbiome data in tumor-associated tissues such as tumor, non-tumor, and lymph nodes, and body fluids such as saliva, gastric juice, pancreatic juice, bile, and feces of patients with pancreatic or biliary tract cancers. The results show that the microbiome of tumor-associated tissues has a very similar bacterial composition, but that in body fluids has different bacterial composition which varies by location, where some bacteria localize to specific body fluids. Surprisingly, Akkermansia was only detected in the bile of patients with biliary tract cancer and its presence was significantly associated with the performance of external biliary drainage (P = 0.041). Furthermore, we found that tumor-associated tissues and body fluids in deep inner body are mostly inhabited by unidentified and uncharacterized bacteria, suggesting that such bacteria may be potential targets for precision therapy in the future.

Loss of Atg2b and Gskip Impairs the Maintenance of the Hematopoietic Stem Cell Pool Size.

A germ line copy number duplication of chromosome 14q32, which contains ATG2B and GSKIP, was identified in families with myeloproliferative neoplasm (MPN). Here, we show that mice lacking both Atg2b and Gskip, but not either alone, exhibited decreased hematopoiesis, resulting in death in utero accompanied by anemia. In marked contrast to MPN patients with duplication of ATG2B and GSKIP, the number of hematopoietic stem cells (HSCs), in particular long-term HSCs, in double-knockout fetal livers was significantly decreased due to increased cell death. Although the remaining HSCs still had the ability to differentiate into hematopoietic progenitor cells, the differentiation efficiency was quite low. Remarkably, mice with knockout of Atg2b or Gskip alone did not show any hematopoietic abnormality. Mechanistically, while loss of both genes had no effect on autophagy, it increased the expression of genes encoding enzymes involved in oxidative phosphorylation. Taken together, our results indicate that Atg2b and Gskip play a synergistic effect in maintaining the pool size of HSCs.

Plasma Sphingosine-1-Phosphate Levels Are Associated with Progression of Estrogen Receptor-Positive Breast Cancer.

Although numerous experiments revealed an essential role of a lipid mediator, sphingosine-1-phosphate (S1P), in breast cancer (BC) progression, the clinical significance of S1P remains unclear due to the difficulty of measuring lipids in patients. The aim of this study was to determine the plasma concentration of S1P in estrogen receptor (ER)-positive BC patients, as well as to investigate its clinical significance. We further explored the possibility of a treatment strategy targeting S1P in ER-positive BC patients by examining the effect of FTY720, a functional antagonist of S1P receptors, on hormone therapy-resistant cells. Plasma S1P levels were significantly higher in patients negative for progesterone receptor (PgR) expression than in those positive for expression (p = 0.003). Plasma S1P levels were also significantly higher in patients with larger tumor size (p = 0.012), lymph node metastasis (p = 0.014), and advanced cancer stage (p = 0.003), suggesting that higher levels of plasma S1P are associated with cancer progression. FTY720 suppressed the viability of not only wildtype MCF-7 cells, but also hormone therapy-resistant MCF-7 cells. Targeting S1P signaling in ER-positive BC appears to be a possible new treatment strategy, even for hormone therapy-resistant patients.

Profiling of host genetic alterations and intra-tumor microbiomes in colorectal cancer.

Some bacteria are symbiotic in tumor tissues, and metabolites of several bacterial species have been found to cause DNA damage. However, to date, the association between bacteria and host genetic alterations in colorectal cancer (CRC) has not been fully investigated. We evaluated the association between the intra-tumor microbiome and host genetic alterations in 29 Japanese CRC patients. The tumor and non-tumor tissues were extracted from the patients, and 16S rRNA genes were sequenced for each sample. We identified enriched bacteria in tumor and non-tumor tissues. Some bacteria, such as Fusobacterium, which is already known to be enriched in CRC, were found to be enriched in tumor tissues. Interestingly, Bacteroides, which is also known to be enriched in CRC, was enriched in non-tumor tissues. Furthermore, it was shown that certain bacteria that often coexist within tumor tissue were enriched in the presence of a mutated gene or signal pathway with mutated genes in the host cells. Fusobacterium was associated with many mutated genes, as well as cell cycle-related pathways including mutated genes. In addition, the patients with a high abundance of Campylobacter were suggested to be associated with mutational signature 3 indicating failure of double-strand DNA break repairs. These results suggest that CRC development may be partly caused by DNA damage caused by substances released by bacterial infection. Taken together, the identification of distinct gut microbiome patterns and their host specific genetic alterations might facilitate targeted interventions, such as modulation of the microbiome in addition to anticancer agents or immunotherapy.

Histopathological characteristics and artificial intelligence for predicting tumor mutational burden-high colorectal cancer.

BACKGROUND: Tumor mutational burden-high (TMB-H), which is detected with gene panel testing, is a promising biomarker for immune checkpoint inhibitors (ICIs) in colorectal cancer (CRC). However, in clinical practice, not every patient is tested for TMB-H using gene panel testing. We aimed to identify the histopathological characteristics of TMB-H CRC for efficient selection of patients who should undergo gene panel testing. Moreover, we attempted to develop a convolutional neural network (CNN)-based algorithm to predict TMB-H CRC directly from hematoxylin and eosin (H&E) slides. METHODS: We used two CRC cohorts tested for TMB-H, and whole-slide H&E digital images were obtained from the cohorts. The Japanese CRC (JP-CRC) cohort (N = 201) was evaluated to detect the histopathological characteristics of TMB-H using H&E slides. The JP-CRC cohort and The Cancer Genome Atlas (TCGA) CRC cohort (N = 77) were used to develop a CNN-based TMB-H prediction model from the H&E digital images. RESULTS: Tumor-infiltrating lymphocytes (TILs) were significantly associated with TMB-H CRC (P < 0.001). The area under the curve (AUC) for predicting TMB-H CRC was 0.910. We developed a CNN-based TMB-H prediction model. Validation tests were conducted 10 times using randomly selected slides, and the average AUC for predicting TMB-H slides was 0.934. CONCLUSIONS: TILs, a histopathological characteristic detected with H&E slides, are associated with TMB-H CRC. Our CNN-based model has the potential to predict TMB-H CRC directly from H&E slides, thereby reducing the burden on pathologists. These approaches will provide clinicians with important information about the applications of ICIs at low cost.

No Venous Thromboembolism Increase Among Transgender Female Patients Remaining on Estrogen for Gender-Affirming Surgery.

BACKGROUND: Both surgery and exogenous estrogen use are associated with increased risk of venous thromboembolism (VTE). However, it is not known whether estrogen hormone therapy (HT) exacerbates the surgery-associated risk among transgender and gender nonbinary (TGNB) individuals. The lack of published data has contributed to heterogeneity in perioperative protocols regarding estrogen HT administration for TGNB patients undergoing gender-affirming surgery. METHODS: A single-center retrospective chart review was performed on all TGNB patients who underwent gender-affirming surgery between November 2015 and August 2019. Surgery type, preoperative HT regimen, perioperative HT regimen, VTE prophylaxis management, outcomes, and demographic data were recorded. RESULTS: A total of 919 TGNB patients underwent 1858 surgical procedures representing 1396 unique cases, of which 407 cases were transfeminine patients undergoing primary vaginoplasty. Of the latter, 190 cases were performed with estrogen suspended for 1 week prior to surgery, and 212 cases were performed with HT continued throughout. Of all cases, 1 patient presented with VTE, from the cohort of transfeminine patients whose estrogen HT was suspended prior to surgery. No VTE events were noted among those who continued HT. Mean postoperative follow-up was 285 days. CONCLUSIONS: Perioperative VTE was not a significant risk in a large, homogenously treated cohort of TGNB patients independent of whether HT was suspended or not prior to surgery.

Gallincin ameliorates colitis-associated inflammation and barrier function in mice based on network pharmacology prediction.

OBJECTIVE: To explore potential mechanisms and effects of gallincin on a mouse model of colitis induced by dextran sulfate sodium (DSS). METHODS: Network pharmacology analysis was used to predict the molecular mechanism of action of gallincin for treatment of colitis. Gallincin was administered orally to mice with DSS-induced colitis. Expression of tumor necrosis factor α (TNF-α), D-lactate, and interleukin-1ß (IL-1ß) and myeloperoxidase activity were assessed with real-time quantitative PCR and an enzyme-linked immunoassay, respectively. Expression of occludin, zonula occludens 1 (ZO-1), and phosphorylated extracellular signal-regulated protein kinase1/2 (p-ERK1/2) was analyzed with immunohistochemical staining and/or western blot assays. RESULTS: Using a network pharmacology approach, 12 mapping targets between gallincin and colitis were obtained, including ERK/mitogen-activated protein kinase. Further investigations in an experimental colitis mouse model showed that gallincin significantly ameliorated experimental colitis, reduced D-lactate levels, and remarkably increased occludin and ZO-1 expression, possibly in part by decreasing IL-1ß, TNF-α, and p-ERK1/2 levels and inhibiting leukocyte penetration. CONCLUSIONS: Gallincin regulated colonic barrier function and reduced colitis-associated inflammation, suggesting it is a promising drug for the treatment of ulcerative colitis.

Genetic profiling for diffuse type and genomically stable subtypes in gastric cancer.

Gastric cancer is one of the most common and clinically important diseases worldwide. The traditional Laeuren classification divides gastric cancer into two histopathological subtypes: diffuse and intestinal. Recent cancer genomics research has led to the development of a new classification based on molecular characteristics. The newly defined genomically stable (GS) subtype shares many cases with the histopathologically diffuse type. In this study, we performed genetic profiling of recurrently and significantly mutated genes in diffuse type and GS subtype tumors. We observed significantly different genetic characteristics, although the two subtypes overlapped in many cases. In addition, based on the profiles of the significantly mutated genes, we identified molecular functions and mutational signatures characteristic of each subtype. These results will advance the clinical application of the diffuse type and GS subtype gastric cancer in precision medicine for treating gastric cancer.

Verification of the Japanese staging system for rectal cancer, focusing on differences with the TNM classification.

PURPOSE: The 9th Japanese Classification of Colorectal Cancer (9th JSCCR) has two main differences from the TNM classification (8th AJCC): first, main or lateral lymph node metastasis is classified as jN3; second, tumor nodules (ND) are treated as lymph node metastasis. In this study, we verified the 9th JSCCR for rectal cancer, focusing on the differences with the 8th AJCC. METHODS: This retrospective analysis involved 212 patients with stage I-III rectal cancer. ND was evaluated using whole-mount sections. We evaluated the relapse-free survival of each staging system, and compared the prognostic significance of the different staging systems using the Akaike information criterion (AIC) and Harrell's concordance index (c-index). RESULTS: Main or lateral lymph node metastasis was detected in nine of 212 (4%) patients. ND was detected in 79 of 212 (37%) patients. The best risk stratification power was observed in the 9th JSCCR (AIC, 759; c-index, 0.708) compared with the 7th JSCCR (AIC, 771; c-index, 0.681), 8th JSCCR (AIC, 768; c-index, 0.696), and the 8th AJCC (AIC, 766; c-index, 0.691). CONCLUSIONS: The 9th JSCCR, which includes the concepts of jN3 and ND, is useful for the risk stratification of rectal cancer, and the contributes to precise decision-making for follow-up management and adjuvant therapy.

RNF43 mutation is associated with aggressive tumor biology along with BRAF V600E mutation in right-sided colorectal cancer.

Right-sided colorectal cancer (RCRC) demonstrates worse survival outcome compared with left-sided CRC (LCRC). Recently, the importance of RNF43 mutation and BRAF V600E mutation has been reported in the serrated neoplasia pathway, which is one of the precancerous lesions in RCRC. It was hypothesized that the clinical significance of RNF43 mutation differs according to primary tumor sidedness. To test this hypothesis, the clinicopathological characteristics and survival outcome of patients with RNF43 mutation in RCRC and LCRC were investigated. Stage I-IV CRC patients (n=201) were analyzed. Genetic alterations including RNF43 using a 415-gene panel were investigated. Clinicopathological characteristics between RNF43 wild-type and RNF43 mutant-type were analyzed. Moreover, RNF43 mutant-type was classified according to primary tumor sidedness, i.e., right-sided RNF43 mutant-type or left-sided RNF43 mutant-type, and the clinicopathological characteristics between the two groups were compared. RNF43 mutational prevalence, spectrum and frequency between our cohort and TCGA samples were compared. RNF43 mutation was observed in 27 out of 201 patients (13%). Multivariate analysis revealed that age (≥65), absence of venous invasion, and BRAF V600E mutation were independently associated with RNF43 mutation. Among the 27 patients with RNF43 mutation, 12 patients were right-sided RNF43 mutant-type and 15 left-sided RNF43 mutant-type. Right-sided RNF43 mutant-type was significantly associated with histopathological grade 3, presence of lymphatic invasion, APC wild, BRAF V600E mutation, microsatellite instability-high (MSI-H), and RNF43 nonsense/frameshift mutation compared with left-sided RNF43 mutant-type. Similarly, RNF43 nonsense/frameshift mutations were more frequently observed in RCRC compared with LCRC in the TCGA cohort (P=0.042). Right-sided RNF43 mutant-type exhibited significantly worse overall survival than RNF43 wild-type and left-sided RNF43 mutant-type (P=0.001 and P=0.023, respectively) in stage IV disease. RNF43 mutation may be a distinct molecular subtype which is associated with aggressive tumor biology along with BRAF V600E mutation in RCRC.

BRAF V600E and SRC mutations as molecular markers for predicting prognosis and conversion surgery in Stage IV colorectal cancer.

Comprehensive genomic sequencing (CGS) enables us to detect numerous genetic alterations in a single assay. We aimed to identify molecular markers for predicting prognosis and conversion surgery in Stage IV colorectal cancer (CRC) using CGS. One-hundred eleven patients with Stage IV CRC who underwent primary tumor resection were analyzed. We retrospectively investigated genetic alterations using CGS of a 415-gene panel. Clinicopathological variables and genetic alterations were analyzed to identify independent prognostic factors of overall survival (OS). Forty-five of 111 patients had R0 resection; of these, 11 patients underwent conversion surgery. Univariate and multivariate analyses identified histopathological grade 3, R0 resection, BRAF V600E mutation, and SRC mutation as independent prognostic factors for OS (P = 0.041, P = 0.013, P = 0.005, and P = 0.023, respectively). BRAF V600E and SRC mutations were mutually exclusive, and SRC mutation was significantly associated with left-sided tumor and liver metastasis compared to BRAF V600E mutation (P = 0.016 and P = 0.025, respectively). Eleven of the 74 initially unresectable patients underwent conversion surgery for R0 resection, yet none harbored BRAF V600E or SRC mutations. BRAF V600E and SRC mutations are important molecular markers which can predict prognosis and conversion surgery in Stage IV CRC.

SMAD4 alteration associates with invasive-front pathological markers and poor prognosis in colorectal cancer.

AIMS: SMAD4 acts as a tumour suppressor, and the loss of SMAD4 is associated with poor prognosis in colorectal cancer (CRC) patients. Although next-generation sequencing (NGS) enabled us to detect numerous genetic alterations in a single assay, the clinical significance of SMAD4 alteration detected with NGS has not been fully investigated. The aim of this study was to evaluate the clinicopathological characteristics and clinical significance of SMAD4 alteration detected with NGS in CRC. METHODS AND RESULTS: We retrospectively investigated 201 patients with stage I-IV CRC, by using a 415-gene panel. To analyse the relationship between SMAD4 alteration and other clinicopathological characteristics, we evaluated clinicopathological variables, including invasive-front pathological markers: tumour budding, poorly differentiated cluster, and Crohn-like lymphoid reaction. Fifty-six patients (28%) had SMAD4 alteration: 24 and 32 patients had SMAD4 mutation and deletion, respectively. SMAD4 alteration was significantly associated with T category (P = 0.027), N category (P = 0.037), M category (P = 0.028), and invasive-front pathological markers, such as poorly differentiated cluster grade 3 (P = 0.020) and absence of Crohn-like lymphoid reaction (P = 0.004). Immunohistochemistry revealed that SMAD4 alteration was significantly associated with loss of SMAD4 (P = 0.023). In 90 patients with stage I-III disease, SMAD4 alteration was significantly associated with poor prognosis for relapse-free and overall survival (P = 0.047; P = 0.022, respectively). Conversely, in 111 patients with stage IV disease, SMAD4 alteration was not significantly associated with overall survival. CONCLUSION: SMAD4 alteration is associated with invasive-front pathological markers and poor prognosis in stage I-III CRC patients.

Identification of TRA-1-60-positive cells as a potent refractory population in follicular lymphomas.

Despite receiving rituximab-combined chemotherapy, follicular lymphoma (FL) patients often suffer tumor recurrence and understand that the cause of relapse in FL would thus significantly ameliorate the tumor therapeutics. In the present study, we show that TRA-1-60-expressing cells are a unique population in FL, converge to the conventional stem cell marker Oct3/4 and ALDH1-positive population, and resist current B-lymphoma agents. TRA-1-60 expression was observed in scattered lymphoma cells in FL tissues only as well as in resting B-lymphocytes inside germinal centers. Retrospective comparison between recurrent and cognate primary tissues showed that the number of TRA-1-60-positive cells from rituximab, cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisone (R-CHOP)-treated FL had increased relative to primary tissue, a finding corroborated by assays on different rituximab-treated FL cell lines, FL-18 and DOHH2, wherein TRA-positive cell numbers increased over 10-fold compared to the untreated sample. Concordantly, scanty TRA-1-60-positive FL-18 cells implanted s.c. into mice evinced potent tumor-initiating capacity in vivo, where tumors were 12-fold larger in volume (P = 0.0021 < 0.005) and 13-fold heavier in weight (P = 0.0015 < 0.005) compared to those xenografted from TRA-negative cells. To explain these results, gene expression profiling and qPCR analysis indicated that TRA-1-60-positive cells defined a distinct population from that of TRA-negative cells, with upregulation of multiple drug transporters and therapeutic resistance genes. Hence, TRA-1-60-expressing cells in FL are considered to be vigorously intractable against conventional therapeutic agents, which may explain its refractory recurrence.