Abstract. Cancer stem cells (CSCs) exhibit self-replication, self-differentiation, drug resistance and immune evasion activities. In recent years CSCs have become increasingly important for the treatment of malignant tumors. CSCs express specific markers, including cluster of differentiation (CD)44, CD44 variant 9 (CD44v9), ATP-binding cassette sub-family G member 2 (ABCG2), CD24, B lymphoma Mo-MLV insertion region 1 homolog (BMI-1) and aldehyde dehydrogenase 1 (ALDH1). However, the prognostic value of their expression in patients with oral squamous cell carcinoma (OSCC) are not well known. The present study evaluated these markers in stage I and II patients with OSCC and examined the association between T classification, histological differentiation, classification of invasion mode, lymph node metastasis and disease-free survival rate. Tissue specimens were obtained from 70 patients with stage I or II OSCC following either surgery or biopsy. Immunohistochemistry was performed and positive staining was defiend as 10% positive cells. CD44 and CD44v9 expressions were strongly detected in all OSCC tissues compared with normal epithelial cells. A total of 22 (31.4%) cases expressed ABCG2 and there was a significant association between ABCG2 expression and invasion. A total of 41 cases (59.0%) expressed CD24 and there was a significant association between CD24 expression and invasion. A total of 33 cases (47.1%) expressed BMI-1 and there was a significant association between BMI-1 expression and the disease-free survival rate. A total of 18 cases (25.7%) expressed ALDH1.Although there was no association between ALDH1 expression and T classification, there were significant associations between ALDH1 expression and histological differentiation, invasion mode, metastasis and the disease-free survival rate. Multivariate analysis revealed that ALDH1 expression was the only prognostic factor for disease-free survival rate. The results of the present study suggest that the positivity of ALDH1 detected in patients with OSCC correlates with the number of cells undergoing epithelial mesenchymal transition and metastasis. These findings indicated that the expression of ALDH1 may be an effective prognostic marker indicating the survival of patients with stage I and II OSCC. IntroductionCancer stem cells (CSCs) are functionally defined by their extensive self-renewal capacity. CSC confers increased radioand chemoresistance in tumors, resulting in tumor recurrence and metastatic spread. Therefore, identification of the regulators that control the tumorigenic potential of CSCs might provide new therapeutic strategies against CSCs to improve cancer treatment. The CSC theory suggests that only a few cancer cells with a capacity for high tumorigenicity, self-renewal, and differentiation are responsible for the maintenance and growth of tumors. Similar to normal tissue stem cells, CSCs can also exist within a supportive niche (1).Oral squamous cell carcinoma (OSCC) patients in stage I and II are mainly treated by surgery and almost all...

The prevalence of NT and ET on CT was lower than that of palatine and lingual tonsilloliths. However, since they are encountered more frequently than clinically significant calcifying diseases such as retropharyngeal calcific tendinitis, clinicians should be able to correctly diagnose NT and ET based on their anatomical features.

Carbonate apatite (CO3Ap) granules are useful as a bone substitute because they can be remodeled to new natural bone in a manner that conforms to the bone remodeling process. However, reconstructing large bone defects using CO3Ap granules is difficult because of their granular shape. Therefore, we fabricated CO3Ap honeycomb blocks (HCBs) with continuous unidirectional pores. We aimed to elucidate the tissue response and availability of CO3Ap HCBs in the reconstruction of rabbit mandibular bone defects after marginal mandibulectomy. The percentages of the remaining CO3Ap area and calcified bone area (newly formed bone) were estimated from the histological images. CO3Ap area was 49.1 ± 4.9%, 30.3 ± 3.5%, and 25.5 ± 8.8%, whereas newly formed bone area was 3.0 ± 0.6%, 24.3 ± 3.3%, and 34.7 ± 4.8% at 4, 8, and 12 weeks, respectively, after implantation. Thus, CO3Ap HCBs were gradually resorbed and replaced by new bone. The newly formed bone penetrated most of the pores in the CO3Ap HCBs at 12 weeks after implantation. By contrast, the granulation tissue scarcely invaded the CO3Ap HCBs. Some osteoclasts invaded the wall of CO3Ap HCBs, making resorption pits. Furthermore, many osteoblasts were found on the newly formed bone, indicating ongoing bone remodeling. Blood vessels were also formed inside most of the pores in the CO3Ap HCBs. These findings suggest that CO3Ap HCBs have good osteoconductivity and can be used for the reconstruction of large mandibular bone defects. Graphical Abstract

Programmed cell death-1 (PD-1) and its ligand programmed cell death 1 ligand 1 (PD-L1) are immune checkpoint inhibitors that play an important role in the host immune avoidance mechanism of tumors. The relationship between PD-L1 expression and malignancy has been reported in various types of cancer, such as lung and gastric cancer. In addition, epithelial-mesenchymal transition (EMT) of cancer cells is deeply involved in the invasion and metastasis of cancer. It has been reported that zinc finger E-box binding homeobox 1 (ZEB-1), an EMT inducer, contributes to metastasis in pancreatic and colon cancer. The present study aimed to investigate the relationship between the expression patterns of two markers, PD-L1 and ZEB-1, and clinicopathological characteristics and prognosis of oral squamous cell carcinoma (OSCC). Biopsy or surgical excision specimens from 169 patients with OSCC were used in the present study. Immunohistochemical staining with monoclonal anti-PD-L1 antibody and anti-ZEB-1 antibody was conducted. Cases with >1% tumor cells positive for PD-L1 and those with >10% tumor cells positive for ZEB-1 were considered positive, respectively. The findings revealed that individual expression of PD-L1 and ZEB-1 in OSCC was not associated with tumor size, degree of differentiation or Yamamoto-Kohama invasion pattern classification. However, co-expression of PD-L1 and ZEB-1 was associated with higher cervical lymph node metastasis and a lower survival rate. In conclusion, the results of the present study indicated that co-expression of PD-L1 and ZEB-1 could serve as a potential marker for the prognosis of patients with OSCC.

This report describes a rare case of a fishbone that penetrated the tongue and moved toward the hyoid bone. An 84-year-old woman was referred to the department with the chief complaint of pain and swelling in her tongue. After anti-inflammatory therapy, a fishbone-like foreign body was detected in the tongue through computed tomographic and ultrasonographic examinations. Since a CT scan performed the day before the operation had revealed that the foreign body had moved from the dorsum of the tongue to near the hyoid bone, it was removed by means of a skin incision, using intraoperative ultrasonography under general anesthesia. The removed foreign body was a needle-shaped 25 mm fishbone. There was no postoperative infection or other complication. In conclusion, it is important to obtain a detailed medical history and to use imaging for detecting foreign bodies in soft tissue and determining their position. Furthermore, it is vital to reconfirm the position just before the operation. Intraoperative ultrasonography is useful for improving the accuracy of the operation because it enables detection of the foreign body in real time.