Prognostic effect of programmed cell death ligand 1/programmed cell death 1 expression in cancer stem cells of human oral squamous cell carcinoma.

The relationship between cancer stem cells (CSCs) in oral squamous cell carcinoma (OSCC) and programmed cell death ligand 1 (PD-L1)/programmed cell death 1 (PD-1) remains unclear. Therefore, the present study aimed to clarify the association between the CD44v3high/CD24low immunophenotype of CSCs in OSCC and PD-L1/PD-1 co-expression, and to assess the prognostic effect of CSCs in terms of immune checkpoint molecules. Formalin-fixed, paraffin-embedded tissue samples and clinicopathological data from 168 patients with OSCC were retrospectively retrieved. Immunohistochemical staining and reverse transcription quantitative polymerase chain reaction were applied to a tissue microarray of the invasive front of each case. Semi-automated cell counting was used to assess CD44v3, CD24, PD-L1 and PD-1 expression by immunohistochemistry (IHC) using a digital image analysis program. Associations between immunological markers and clinicopathological variables were estimated. Patients with the CSC immunophenotype CD44v3high/CD24low, and patients with a high PD-L1/PD-1-positive cell density in the tumor parenchyma and stroma had significantly lower survival rates. Furthermore, patients with the CSC immunophenotype (CD44v3high/CD24low) and high PD-L1/PD-1 co-expression had even lower survival rates (P<0.01, log-rank test). Notably, there was a positive correlation between CD44v3 and PD-L1 expression (τ=0.1096, P=0.0366, Kendall rank correlation coefficient) and a negative correlation between CD24 and PD-1 expression (τ=-0.1387, P=0.0089, Kendall rank correlation coefficient). Additionally, the high CD44v3 expression group, as determined by IHC, exhibited significantly decreased expression of U2 small nuclear RNA auxiliary factor 1 (U2AF1) at the mRNA level compared with that in the low CD44v3 expression group (P<0.001, Mann-Whitney U test), and U2AF1 and PD-L1 mRNA expression exhibited a significant negative correlation (τ=-0.3948, P<0.001, Kendall rank correlation coefficient). In conclusion, CSCs in OSCC may evade host immune mechanisms and maintain CSC stemness via PD-L1/PD-1 co-expression, resulting in unfavorable clinical outcomes.

Clinical Application of the IllumiScan Fluorescence Visualization Device in Detecting Oral Mucosal Lesions.

OBJECTIVE: Fluorescence visualization devices are screening devices that can be used to examine lesions of the oral mucosa non-invasively. We observed oral squamous cell carcinoma (OSCC) and leukoplakia using the IllumiScan (Shofu, Kyoto, Japan) fluorescence visualization device and examined its usefulness and characteristics. METHODS: We investigated 31 OSCC and nine leukoplakia in patients who were examined using the IllumiScan and treated in our department from January 2017 to February 2018. Images taken with the IllumiScan were analyzed using image analysis software. We also examined the lesions using narrowband imaging (NBI). Additionally, the IllumiScan and NBI images and the non-stained areas of iodine staining method (IOM) were visually evaluated. RESULTS: The average luminance of OSCC in the keratinized mucosa was significantly lower than that of OSCC in non-keratinized mucosa. The average luminance of OSCC was significantly lower than that of leukoplakia. Even in keratinized mucosa where IOM is impossible to use, the OSCC lesion exhibited fluorescence visualization loss. CONCLUSION: The application of the fluorescence visualization device to the oral mucosa may be useful for distinguishing between cancer and normal areas and can be used to detect OSCC in the keratinized mucosa. The use of the IllumiScan in combination with other conventional screening methods may lead to a better diagnosis.

Adenosquamous Carcinoma in the Midline Dorsum of the Tongue: A Rare Case Report.

Adenosquamous carcinoma (ASC) is a rare malignant tumor of the oral and maxillofacial region that displays histologic features of both adenocarcinoma and squamous cell carcinoma. ASC in the midline dorsum of the tongue is exceedingly rare. We report the case of a 48-year-old man who presented with a painless mass in the midline dorsum of the tongue. Although the case was diagnosed as adenocarcinoma by biopsy, a final diagnosis of ASC was established after surgery. Ten months after the patient's initial visit, no recurrence or metastasis has been noted. ASC in the middle dorsum of the tongue is exceedingly rare, and no examples have been reported hitherto.

Diagnostic dilemma of IgG4-related primary localized cervical lymphadenopathy associated with aberrant IL-6 expression level.

BACKGROUND: Immunoglobulin G4-related disease (IgG4-RD) is a recently recognized inflammatory condition with single- or multi-organ involvement. The disease is characterized by tumefactive lesions with dense IgG4 plasmacytic infiltration (an elevated IgG4(+)/IgG(+) cell ratio of > 40 %), storiform fibrosis, and obliterative phlebitis, with or without elevated serum IgG4 levels. The diagnostic criteria for IgG4-RD, proposed in 2011, were quite comprehensive and practical; however, it is important to remember that other diseases, such as hyper-interleukin (IL)-6 syndromes, may have common histopathological findings. Therefore, the histopathology of suspected IgG4-RD is occasionally not diagnostic. Here, we report a case of IgG4-related primary localized cervical lymphadenopathy without any other organ involvement. To our knowledge, there have been no previous reports of this. Additionally, the disease was associated with a 20-fold increase in IL-6 levels compared to that of the normal range. CASE PRESENTATION: We report the case of a 52-year-old Japanese man who presented with a painless, somewhat diffuse swelling in the left submandibular region. Although the case fulfilled diagnostic criteria for IgG4-RD, the diagnosis was not straightforward due to abnormally high levels of serum IL-6. After systematic evaluation of the patient, a final diagnosis of IgG4-RD was established. Since then, a specialist in connective tissue disorders has evaluated the patient on a regular basis. Two years after his initial visit, no disease progress or systemic involvement has been noted. CONCLUSION: We present a case of an IgG4-related primary localized cervical lymphadenopathy mimicking hyper-IL-6 syndrome. This case can serve as an excellent reminder that the definitive diagnosis of IgG4-RD should be established using a systematic approach, in particular when it appears as an atypical manifestation.

The expression of arginase-1, keratin (K) 8 and K18 in combined hepatocellular-cholangiocarcinoma, subtypes with stem-cell features, intermediate-cell type.

AIMS: The WHO classification describes that combined hepatocellular-cholangiocarcinoma, subtypes with stem-cell features, intermediate-cell subtype (CHC-INT) is composed of tumour cells with features intermediate between hepatocytes and cholangiocytes. However, we previously reported that CHC-INT showed a high positive rate of biliary markers, but the expression of hepatocyte paraffin (HepPar)-1 was low. In this study, we examined the expression of other hepatocyte markers, such as arginase-1 (Arg-1), keratin (K) 8 and K18 in CHC-INT in order to examine the utility of pathological diagnosis in CHC-INT. METHODS: We performed immunohistochemistry (IHC) of Arg-1, K8 and K18 using 32 previously diagnosed as CHC-INT. Immunoreactivity was evaluated with grading from 0 to 4 according to the distribution area of positive cells. The obtained findings of Arg-1, K8 and K18 were compared with those of K7, K19 and HepPar-1. RESULTS: Out of the 32 cases, 22 (68.8%) cases were positive for Arg-1. Twenty-five (78.1%) were positive for K8. The IHC scores of Arg-1 and K8 were significantly higher than those of HepPar-1, but significantly lower than those of K7 and K19. The K18 expression was widely observed in all cases (100%). The IHC score of Arg-1 and K8 in CHC-INT was intermediate between hepatocellular carcinoma and cholangiocarcinoma. CONCLUSIONS: Arg-1 and K8 were good markers to identify intermediate cells between hepatocytes and cholangiocytes. These can be useful markers for pathological diagnosis of CHC-INT, which usually has wide histological diversities, in combination with other hepatocytic and/or cholangiocytic markers.

Growth inhibitory effect of an injectable hyaluronic acid-tyramine hydrogels incorporating human natural interferon-α and sorafenib on renal cell carcinoma cells.

Immunotherapy including interferon-alpha (IFN-α) is one of the treatment options for metastatic renal cell carcinoma (mRCC) patients. Despite clinical benefits for the selected patients, IFN-α therapy has some problems, such as poor tolerability and dose-limiting adverse effects. In addition, the frequent injections reduce a patient's quality of life and compliance. Recently, an injectable and biodegradable hydrogel system to prolong drug release is reported. In this study, we investigated the anticancer effect of IFN-α (Sumiferon®)-incorporated hyaluronic acid-tyramine (HA-Tyr) hydrogels in human RCC-xenografted in nude mice. We also evaluated the synergistic efficacy of IFN-α-incorporated HA-Tyr hydrogels+sorafenib in this model. IFN-α-incorporated HA-Tyr hydrogels+sorafenib most effectively inhibited tumor growth on human RCC cells xenografted in nude mice. In addition, IFN-α-incorporated HA-Tyr hydrogels+sorafenib inhibited the proliferation of tumor in nude mice by inducing apoptosis and the suppression of angiogenesis. Our results suggest a possibility that HA-Tyr hydrogel drug delivery system prolongs the biological half-life of natural human IFN-α and enhances its anticancer effects on human RCC cells. STATEMENT OF SIGNIFICANCE: The scope of this study is to provide an alternative approach to improve the anticancer efficacy in renal cell carcinoma (RCC) treatment by using hyaluronic acid-tyramine (HA-Tyr) hydrogel drug delivery system. We investigated the anticancer effect of natural interferon-α (IFN-α)-incorporated HA-Tyr hydrogels in RCC cells. We also evaluated the synergistic efficacy of natural human IFN-α-incorporated HA-Tyr hydrogels+sorafenib. We demonstrated that HA-Tyr hydrogel system is able to release natural human IFN-α in sustained manner and enhances its anticancer effects on human RCC cells. In addition, we suggested that IFN-α-incorporated HA-Tyr hydrogels+sorafenib exhibited most effectively anticancer effects. Hence, we believe that this approach could be applied to treatment with RCC in the future.

CD44v3+/CD24- cells possess cancer stem cell-like properties in human oral squamous cell carcinoma.

Cancer stem cells (CSCs) or cancer stem cell-like cells (CSC-LCs) are a minority population of cells that relate to tumor progression, metastasis and drug resistance. To identify CSC-LCs in oral squamous cell carcinoma (OSCC), we used two OSCC cell lines, SAS and OSC20, and cell surface markers, CD44v3 and CD24. In addition, we examined CD44v3 and CD24 expression immunohistochemically and evaluated the relationship between the expression and clinicopathological parameters in 50 OSCC tissues. In SAS and OSC20, CD44v3+/CD24- cells showed a higher sphere forming ability than the other fractions, i.e., CD44v3+/CD24+, CD44v3-/CD24- and CD44v3-/CD24+ cells. The proportion of CD44v3+/CD24- cells in SAS and OSC20 was 10.7 and 24.1%, respectively. Regarding SAS, CD44v3+/CD24- cells also showed a higher drug resistance for CDDP, 5-FU and cetuximab and expressed higher mRNA levels of CSC property-related genes than the other cell fractions. The tumorigenicity of CD44v3+/CD24- cells was not significantly different from the other fractions in SAS. An immunohistochemical study revealed a significant correlation between CD44v3 expression in the invasive portion and lymph node metastasis. Kaplan Meier analysis revealed cases with CD44v3 expression in the invasive portion tended to show poor overall survival (OS) compared with those without CD44v3, and there was a significant difference in OS between CD44v3+/CD24- and CD44v3-/CD24- immunophenotypes in the invasive portion. In conclusion, the results suggest that the CD44v3+/CD24- cell population displays CSC-LC properties in a human OSCC cell line. Additionally, we present evidence that CD44v3 immunoexpression and CD44v3+/CD24- immunophenotypes could give prognostic information associated with unfavorable clinical outcomes.

Neurogenic pulmonary edema following Cryptococcal meningoencephalitis associated with HIV infection.

Neurogenic pulmonary edema (NPE) is a clinical syndrome characterized by the acute onset of pulmonary edema following a significant central nervous system insult. Only a few cases of NPE after Cryptococcal meningitis have been reported. We report a case of NPE following Cryptococcal meningoencephalitis. A 40-year-old man with no medical history was hospitalized for disturbance of consciousness. Blood glucose level was 124 mg/dL. Non-contrast head computed tomography showed no abnormalities. Lumbar puncture revealed a pressure of over 300 mm H2 O and cerebrospinal fluid (CSF) confirmed a white blood cell count of 65/mm(3) . The CSF glucose level was 0 mg/dL. The patient was empirically started on treatment for presumptive bacterial and viral meningitis. Four days after, the patient died in a sudden severe pulmonary edema. Autopsy was performed. We found at autopsy a brain edema with small hemorrhage of the right basal ganglia, severe pulmonary edema and mild cardiomegaly. Histologically, dilated Virchow-Robin spaces, crowded with Cryptococci were observed. In the right basal ganglia, Virchow-Robin spaces were destroyed with hemorrhage and Cryptococci spread to parenchyma of the brain. No inflammatory reaction of the lung was seen. Finally, acute pulmonary edema in this case was diagnosed as NPE following Cryptococcal meningoencephalitis. After autopsy, we found that he was positive for serum antibodies to human immunodeficiency virus.

Metastatic gastric tube cancer detected in a resected mandibular bone with osteoradionecrosis.

Osteoradionecrosis (ORN) of the jaw is an intractable complication of radiotherapy for head and neck cancer. However, osteolytic lesions are often hard to distinguish from malignancies. We report a rare case of metastatic cancer in a resected mandibular bone after segmental resection for ORN of the jaw. A 63-year-old male with a history of subtotal oesophageal resection for oesophageal cancer and reconstruction of the oesophagus with a gastric tube subsequently developed ORN of the jaw. Conservative treatment was unsuccessful and pathological fracture of the necrotic mandible occurred. The patient underwent segmental resection of the mandible and adenocarcinoma was detected in the resected mandibular bone. Immunohistochemical staining for cytokeratin 7 and 20 revealed that the adenocarcinoma had metastasized from the reconstructed gastric tube. This case highlights the fact that cancers of the gastric tube may metastasize to radiation-induced necrotic bone tissue in the mandible.

Evaluation of immunohistochemistry using two different antibodies and procedures for primary lung adenocarcinoma harboring anaplastic lymphoma kinase rearrangement.

Rearrangements of anaplastic lymphoma kinase (ALK) have been recently identified in non-small cell lung carcinomas. Previous studies have revealed characteristic features, including adenocarcinoma histology and mucin production, in ALK-positive lung carcinoma. The present study evaluated immunohistochemistry (IHC) in ALK-positive lung carcinoma using two different antibodies, clone 5A4 and D5F3, and compared the results. On the basis of the aforementioned characteristic features, out of 359 primary lung carcinomas, the ALK status of 14 adenocarcinomas was screened using the intercalated antibody-enhanced polymer (iAEP) method with antibody 5A4, and this was compared with the ALK status obtained using rabbit monoclonal antibody D5F3 and fluorescence in situ hybridization for ALK. Eight cases were demonstrated to be ALK-positive by IHC. Seven cases exhibited ALK rearrangement, which was demonstrated by fluorescence in situ hybridization. The IHC for ALK obtained using D5F3 was comparable with that of the iAEP and exhibited low heterogeneity. This finding suggests that IHC for ALK could be useful in limited tissue samples, such as biopsy specimens or cytology, for the screening of ALK-positive lung carcinoma. In the present study, it was demonstrated that IHC with ALK monoclonal antibody D5F3 was useful for screening lung adenocarcinoma harboring ALK rearrangement.

Side population cell fractions from hepatocellular carcinoma cell lines increased with tumor dedifferentiation, but lack characteristic features of cancer stem cells.

BACKGROUND AND AIM: Cancer stem cells (CSCs), a minority population with stem cell-like characteristics, play important roles in cancer development and progression. Putative CSC markers, such as CD13, CD90, CD133, and epithelial cell adhesion molecule (EpCAM), and side population (SP) technique are generally used in an attempt to isolate CSCs. We aimed to clarify the relationship between CSCs and clonal dedifferentiation in hepatocellular carcinoma (HCC). METHODS: We used a well-differentiated HCC cell line (HAK-1A) and a poorly differentiated HCC cell line (HAK-1B) established from a single nodule with histological heterogeneity. HAK-1B arose because of clonal dedifferentiation of HAK-1A. The SP cells and non-SP (NSP) cells were isolated from the two cell lines with a FACSAria II and used for the analyses. RESULTS: The SP cell fractions in HAK-1A and HAK-1B were 0.2% and 0.9%, respectively. CD90 or EpCAM was not expressed in either HAK-1A or HAK-1B, while CD13 and CD133 were expressed in HAK-1B alone. Although sphere forming ability, tumorigenicity, growth rate, and CD13 expression were higher in HAK-1B SP cells than HAK-1B NSP cells, there were no differences in drug resistance, colony forming ability, or cell cycle rates between HAK-1B SP and NSP cells, suggesting HAK-1B SP cells do not fulfill CSC criteria. CONCLUSIONS: Our findings suggested a possible relationship between the expression of CSC markers and clonal dedifferentiation. However, the complete features of CSC could not be identified in SP cells, and the concept of SP cells as a universal marker for CSC may not apply to HAK-1A and HAK-1B.

Pegylated interferon-α2a inhibits proliferation of human liver cancer cells in vitro and in vivo.

PURPOSE: We investigated the effects of pegylated interferon-α2a (PEG-IFN-α2a) on the growth of human liver cancer cells. METHODS: The effect of PEG-IFN-α2a on the proliferation of 13 liver cancer cell lines was investigated in vitro. Cells were cultured with medium containing 0-4,194 ng/mL of PEG-IFN-α2a, and after 1, 2, 3, or 4 days of culture, morphologic observation and growth assay were performed. After hepatocellular carcinoma (HCC) cells (HAK-1B and KIM-1) were transplanted into nude mice, various doses of PEG-IFN-α2a were subcutaneously administered to the mice once a week for 2 weeks, and tumor volume, weight, and histology were examined. RESULTS: PEG-IFN-α2a inhibited the growth of 8 and 11 cell lines in a time- and dose-dependent manner, respectively, although the 50% growth inhibitory concentrations of 7 measurable cell lines on Day 4 were relatively high and ranged from 253 ng/mL to 4,431 ng/mL. Various levels of apoptosis induction were confirmed in 8 cell lines. PEG-IFN-α2a induced a dose-dependent decrease in tumor volume and weight, and a significant increase of apoptotic cells in the tumor. Subcutaneous administration of clinical dose for chronic hepatitis C (3 µg/kg, 0.06 µg/mouse) was effective and induced about 30-50% reduction in the tumor volume and weight as compared with the control. CONCLUSIONS: Although in vitro anti-proliferative effects of PEG-IFN-α2a were relatively weak, PEG-IFN-α2a induced strong anti-tumor effects on HCC cells in vivo. The data suggest potential clinical application of PEG-IFN-α2a for the prevention and treatment of HCC.

A case of metastasizing pleomorphic adenoma in the maxillary bone appearing twenty years after initial resection of pleomorphic adenoma of the hard palate.

Metastasizing pleomorphic adenoma (MPA) is the inexplicable metastasis of a histologically benign pleomorphic adenoma (PA). Approximately 50 cases have been reported. A 62-year-old woman noticed pain in the upper molar area. Her medical history included an operation for PA in the hard palate that was performed 20 years previously. On imaging, four relatively well-defined lesions were demonstrated in the maxillary bone. She underwent an operation for these lesions. Each lesion revealed the same histological features. Morphological findings displayed typical features of PA. Immunohistochemical staining showed that tumor cells of both primary and metastasizing lesions were positive for pleomorphic adenoma gene (PLAG) 1, which is a sensitive marker for PA. Gene fusions involving PLAG1 were examined by reverse transcription-polymerase chain reaction. However, no gene rearrangements of PLAG1 were found. We report here on a case of MPA in the maxillary bone, which appeared 20 years after resection of the primary tumor and review the relevant literature.

Aldehyde dehydrogenase 1 identifies cells with cancer stem cell-like properties in a human renal cell carcinoma cell line.

Cancer stem cells (CSC) or cancer stem cell-like cells (CSC-LCs) have been identified in many malignant tumors. CSCs are proposed to be related with drug resistance, tumor recurrence, and metastasis and are considered as a new target for cancer treatment; however, there are only a few reports on CSCs or CSC-LCs in renal cell carcinoma (RCC). Different approaches have been reported for CSC identification, but there are no universal markers for CSC. We used two different approaches, the traditional side population (SP) approach, and the enzymatic (aldehyde dehydrogenase 1 (ALDH1)) approach to identify CSC-LC population in two RCC cell lines, ACHN and KRC/Y. We found that ACHN and KRC/Y contain 1.4% and 1.7% SP cells, respectively. ACHN SP cells showed a higher sphere forming ability, drug resistance, and a slightly higher tumorigenic ability in NOD/SCID mice than Non-SP (NSP) cells, suggesting that cells with CSC-LC properties are included in ACHN SP cells. KRC/Y SP and NSP cells showed no difference in such properties. ALDH1 activity analysis revealed that ACHN SP cells expressed a higher level of activity than NSP cells (SP vs. NSP: 32.7% vs 14.6%). Analysis of ALDH1-positive ACHN cells revealed that they have a higher sphere forming ability, self-renewal ability, tumorigenicity and express higher mRNA levels of CSC-LC property-related genes (e.g., ABC transporter genes, self-replication genes, anti-apoptosis genes, and so forth) than ALDH1-negative cells. Drug treatment or exposure to hypoxic condition induced a 2- to 3-fold increase in number of ALDH1-positive cells. In conclusion, the results suggest that the ALDH1-positive cell population rather than SP cells show CSC-LC properties in a RCC cell line, ACHN.