Tumor thickness as a novel risk factor for lymph node metastasis by superficial squamous cell carcinoma of head and neck.

Narrow-band imaging combined with magnified endoscopy has enabled the detection of superficial squamous cell carcinoma of the head and neck (SSCCHN) that has been resected with minimally invasive treatment, preserving vocalization and swallowing functions. However, risk factors of lymph node metastasis (LNM) must be identified, as some patients with LNM have a poor prognosis. From an initial 599 patients with 700 lesions who underwent trans-oral surgery in 27 Japanese hospitals (a nationwide registration survey), we enrolled 541 patients with 633 SSCCHNs, as indicated by central pathological diagnoses. All pathological specimens for each patient were examined using 20 pathological factors that are thought to affect the LNM of SSCCHN. In all, 24 (4.4%) of the 568 SSCCHNs exhibited LNM, and all 24 had at least one solitary nest of epithelial neoplastic cells present in the stroma, clearly separated from the intraepithelial carcinoma. Multivariate analysis also showed that tumor thickness (p = 0.0132, RR: 7.85, 95% confidence interval [CI]: 1.54-40.02), and an INFc pattern classified as infiltrating growth (INF) with unclear boundaries between tumor and non-tumor tissues (p = 0.0003, RR: 14.47, 3.46-60.46), and tumor budding (p = 0.0019, RR: 4.35, CI: 1.72-11.01) were significantly associated with LNM. Solitary nests may be indicative of LNM. In addition, tumor thickness was revealed to be a risk factor for LNM in SSCCHNs using pT factors that do not include an invasion depth element because of the anatomical absence of the muscularis mucosae.

Insight into the significance of Foxp3 + tumor-infiltrating lymphocytes in squamous cell lung cancer.

PURPOSE: Although developing a better understanding of tumor-infiltrating Foxp3 + lymphocytes (Foxp3 + TILs) might provide essential knowledge to predict response to immunotherapy and prognosis, our current knowledge about Foxp3 + TILs is inadequate. This study investigated the prognostic significance of tumor-infiltrating Foxp3 + lymphocytes (Foxp3 + TILs) in squamous cell lung cancer (SQ-LC) objectively. METHODS: Among patients with SQ-LC surgically resected in our institution between 2011 and 2017, those with pathological stage IA3-IIIA were immunohistochemically studied to evaluate Foxp3 + TILs in their tumor stroma. The impact of Foxp3 + TILs on relapse-free survival (RFS) was analyzed with Kaplan-Meier survival analysis and multivariate analysis using a Cox proportional hazards model/Fine-Gray model. RESULTS: This study analyzed 100 patients. Multivariate analysis showed that a large number of Foxp3 + TILs in the stroma does not associate with a poor prognosis, rather that a large number of Foxp3 + TILs (≥ 64 cells) tend to be associated with a more favorable prognosis than a small number of Foxp3 + TILs (< 64 cells) (large vs small number: HR, 0.56; 95% CI, 0.17-1.83; P = 0.34). Exploratory analysis also showed that in the two populations divided by a difference in Foxp3 expression levels, similar trends to the main analysis were observed. CONCLUSION: Our results showed that a large number of Foxp3 + TILs in the stroma may not associate with a poor prognosis in SQ-LC. To use the seemingly complicated information of Foxp3 + TILs as biomarkers, better understanding the diversity and heterogeneity of Foxp3 + TILs and analyzing their subpopulations that increase in the TME may be needed.

REV7 is involved in outcomes of platinum-based chemotherapy in pancreatic cancer by controlling the DNA damage response.

REV7 is a multifunctional protein implicated in various biological processes, including DNA damage response. REV7 expression in human cancer cells affects their sensitivity to DNA-damaging agents. In the present study, we investigated the significance of REV7 in pancreatic ductal adenocarcinoma (PDAC). REV7 expression was immunohistochemically examined in 92 resected PDAC specimens and 60 endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) specimens of unresectable PDAC treated with platinum-based chemotherapy, and its association with clinicopathologic features was analyzed. Although REV7 expression was not significantly associated with the progression of primary tumors (T-factor and Stage) in either resected or unresectable PDAC, decreased levels of REV7 expression in EUS-FNAB specimens of unresectable PDAC were significantly associated with better outcomes of platinum-based chemotherapy and a favorable prognosis. REV7-deficient PDAC cell lines showed suppressed cell growth and enhanced sensitivity to cisplatin in vitro. Tumor-bearing mice generated using REV7-deficient PDAC cell lines also showed enhanced sensitivity to cisplatin in vivo. RNA sequencing analysis using WT and REV7-deficient PDAC cell lines revealed that REV7 inactivation promoted the downregulation of genes involved in the DNA repair and the upregulation of genes involved in apoptosis. Our results indicate that decreased expression of REV7 is associated with better outcomes of platinum-based chemotherapy in PDAC by suppressing the DNA damage response. It is also suggested that REV7 is a useful biomarker for predicting the outcome of platinum-based chemotherapy and the prognosis of unresectable PDAC and is a potential target for PDAC treatment.

Insight into the significance of CD8+ tumor-infiltrating lymphocytes in squamous cell lung cancer.

BACKGROUND: Although there are great expectations regarding the use of tumor-infiltrating lymphocytes (TILs) to predict effects of immunotherapies and prognosis, knowledge about TILs remains insufficient for clinical application. METHODS: We objectively investigated the prognostic significance of tumor-infiltrating CD8 + lymphocytes (CD8 + TILs) in squamous cell lung cancer (SQ-LC). Among patients who underwent surgical resection of SQ-LC in 2011-2017, 100 patients with pathological stage IA3-III were immunohistochemically studied to evaluate CD8 + TILs in the tumor stroma and parenchyma. The impact of CD8 + TILs on relapse-free survival was analyzed using a Kaplan-Meier survival analysis and multivariate analyses using Fine-Gray and Cox proportional hazards models. RESULTS: The multivariate analysis showed that large and small numbers, but not intermediate numbers, of CD8 + TILs in the tumor stroma may be related to a more favorable prognosis (small vs. intermediate: HR, 0.64; 95% CI: 0.29-1.41, p = 0.27; large vs. intermediate: HR, 0.48; 95% CI: 0.21-1.09, p = 0.08). In contrast, a large number of CD8 + TILs in the tumor parenchyma was associated with a poor prognosis (HR, 2.60; 95% CI: 0.91-7.42, p = 0.075). An exploratory analysis showed a potentially strong association between an extremely large number of CD8 + TILs in the tumor parenchyma and a poor prognosis, even with a large number of CD8 + TILs in the tumor stroma. CONCLUSION: Our study provided partial but important information on the significance of CD8 + TILs in SQ-LC. To use CD8 + TILs as biomarkers, a better understanding of CD8 + TILs as well as other important components in the tumor microenvironment and the inflammatory phenotypes they form may be needed.

Micropapillary and solid components as high-grade patterns in IASLC grading system of lung adenocarcinoma: Clinical implications and management.

OBJECTIVES: The grading system proposed by the International Association for the Study of Lung Cancer is based on a combination of predominant histologic subtypes and the proportion of high-grade components with a cutoff of 20%. We aimed to examine the clinical implications of the grading system beyond the discrimination of patient prognosis, while assessing the biological differences among high-grade subtypes. METHODS: We retrospectively reviewed 648 consecutive patients with resected lung adenocarcinomas and examined their clinicopathologic, genotypic, and immunophenotypic features and treatment outcomes. Besides the differences among grades, the clinical impact of different high-grade components: micropapillary (MIP) and solid (SOL) patterns, was individually evaluated. RESULTS: Survival outcomes were well-stratified according to the grading system. Grade 3 tumors exhibited aggressive clinicopathologic features, while being an independent prognostic factor in multivariable analysis. A small proportion (<20 %) of high-grade components in grade 2 had a negative prognostic impact. The prognostic difference bordering on the 20 % cutoff of the MIP proportion was validated; however, the proportion of SOL component did not affect prognosis. A survival benefit from adjuvant chemotherapy was observed in grade 3 tumors regardless of histologic subtype, but not in grade 1-2 tumors. The molecular and immunophenotypic features were different among grades, but still heterogeneous in grade 3, with MIP harboring frequent EGFR mutation and SOL exhibiting high PD-L1 expression. The treatment outcome after recurrence was worse in grade 3, but tumors with MIP pattern had an equivalent prognosis to that of grade 1-2 tumors, reflecting the high frequency of molecular targeted therapy. CONCLUSIONS: In addition to stratifying patient prognosis, the current grading system could discriminate clinical course, therapeutic effects of adjuvant chemotherapy, and molecular and immunophenotypic features. Further stratification based on biological heterogeneity in grade 3 remains necessary to enhance the role of the grading system in guiding patient management.

Identification of the promoter region regulating the transcription of the REV7 gene.

REV7 is involved in various biological processes including DNA repair and mutagenesis, cell cycle regulation, gene transcription, and carcinogenesis. REV7 is highly expressed in adult testicular germ cells as well as several malignant tumors. REV7 expression levels are associated with prognosis in several human cancers, however, the mechanism of REV7 transcriptional regulation has not been elucidated. In this study, we characterized the promoter region of the REV7 gene. A luciferase reporter assay using the human germ cell tumor cell line NEC8 was utilized to examine the upstream genomic region of REV7 for transcriptional activity, and two transcriptional activation regions were identified. We determined a small genomic region important for transcriptional activation using site-directed mutagenesis; this region is shared by several putative binding motifs for transcription factors, including the cAMP-responsive element modulator (CREM), cAMP-response element binding protein (CREB), and B-lymphocyte-induced maturation protein-1 (BLIMP-1). Exogenous CREM and CREB expression had no effect on the transcriptional activity in NEC8 cells or the human embryonic kidney cell line HEK293T. In contrast, exogenous BLIMP-1 expression increased luciferase reporter activity in HEK293T cells but unexpectedly decreased activity in NEC8 cells. Chromatin immunoprecipitation analysis demonstrated that BLIMP-1 binds to the genomic region near the binding motif in the REV7 promoter. Additionally, BLIMP-1 overexpression promoted endogenous REV7 expression in HEK293T cells. These findings suggest that BLIMP-1 may be a putative transcriptional regulator of REV7 in mammalian cells.

REV7 in Cancer Biology and Management.

DNA repair and cell cycle regulation are potential biological fields to develop molecular targeting therapies for cancer. Human REV7 was originally discovered as a homologous molecule to yeast Rev7, which is involved in DNA damage response and mutagenesis, and as the second homolog of yeast Mad2, involved in the spindle assembly checkpoint. Although REV7 principally functions in the fields of DNA repair and cell cycle regulation, many binding partners of REV7 have been identified using comprehensive analyses in the past decade, and the significance of REV7 is expanding in various other biological fields, such as gene transcription, epigenetics, primordial germ cell survival, neurogenesis, intracellular signaling, and microbial infection. In addition, the clinical significance of REV7 has been demonstrated in studies using human cancer tissues, and investigations in cancer cell lines and animal models have revealed the greater impacts of REV7 in cancer biology, which makes it an attractive target molecule for cancer management. This review focuses on the functions of REV7 in human cancer and discusses the utility of REV7 for cancer management with a summary of the recent development of inhibitors targeting REV7.

Clinicopathological Significance of BRCAness in Resectable Pancreatic Ductal Adenocarcinoma and Its Association With Anticancer Drug Sensitivity in Pancreatic Cancer Cells.

OBJECTIVE: The concept of BRCAness has been proposed as a homologous recombination repair dysfunction triggered by a genetic defect in the BRCA pathway including the BRCA1/2 mutations. A certain number of pancreatic ductal adenocarcinoma (PDAC) patients have BRCAness. However, a large-scale analysis of BRCAness in PDAC has not been performed. In addition, no basic studies have examined the significance of BRCAness in PDAC cell lines. METHODS: Ninety-two patients who underwent surgery for PDAC were enrolled. Formalin-fixed and paraffin-embedded specimens of resected PDACs were used to analyze BRCAness by multiplex ligation-dependent probe amplification. We also analyzed BRCAness in pancreatic cancer cell lines and the sensitivity to cisplatin and olaparib using a colony formation assay. RESULTS: Of the 92 patients with PDAC, 6 were detected to have BRCAness-positive PDAC (6.5%). No significant differences in overall survival and progression-free survival were observed between the BRCAness-positive and BRCAness-negative groups. One PDAC cell line, KP-2, was positive for BRCAness and was more sensitive to cisplatin and olaparib than the BRCAness-negative cell lines. CONCLUSIONS: Our results revealed that a considerable number of PDACs are positive for BRCAness, suggesting that BRCAness status could be a useful biomarker for selecting anticancer treatments for advanced or relapsed PDAC.

The Significance of CD109 Expression in Oropharyngeal Squamous Cell Carcinoma.

BACKGROUND/AIM: Up-regulation of CD109 occurs in malignant tumours, although its role is unknown. Here we aimed to evaluate the significance of CD109 expression in oropharyngeal squamous cell carcinoma (OPSCC). PATIENTS AND METHODS: Immunohistochemical analysis was performed to assess CD109 expression in 169 patients with OPSCC. We assessed the effects of small interfering RNA (siRNA)-mediated inhibition of CD109 expression on the proliferation and invasiveness of the human papillomavirus 16-positive (HPV16+) head and neck SCC cell line UM-SCC-47. RESULTS: Expression of CD109 was associated with higher tumour differentiation in p16+ OPSCC (p=0.0036), and the CD109+ subgroup experienced significantly shorter progression-free survival (p=0.03). UM-SCC-47 cells with siRNA-mediated inhibition of CD109 expression showed reduced invasiveness (p=0.07). CONCLUSION: CD109 expression is associated with poor prognosis of HPV16+ OPSCCs.

Upregulation of REV7 correlates with progression of malignant melanoma.

REV7 is a multifunctional protein implicated in DNA damage tolerance, cell cycle control, and gene expression, and is involved in the carcinogenesis of various human tumors. It has been reported that REV7 expression is associated with ultraviolet-induced mutagenesis; however, the role of REV7 expression in skin cancers, including malignant melanomas, remains unclear. In the present study, we investigated the clinical and biological significance of REV7 in malignant melanoma. Levels of REV7 expression in human skin cancers were evaluated immunohistochemically. Positive expression of REV7 was frequently observed in malignant melanomas, as well as in squamous cell carcinomas and basal cell carcinomas. Enhanced immunoreactivity to REV7 was closely linked with cell proliferation assessed by Ki-67 labeling indexes in the three skin cancers, and was related with tumor thickness in malignant melanomas. REV7 depletion in malignant melanoma cells MEWO and G361 suppressed cell proliferation, migration, and invasion abilities. REV7 depletion also affected the expression of intracellular signaling molecules AKT and ERK in MEWO cells, resulting in downregulation of ERK signal activation. In addition, REV7 depletion facilitated sensitivity to cisplatin, but not to dacarbazine, in MEWO cells. Our results suggest that REV7 expression correlates with disease progression of malignant melanoma.