MiR-34a inhibits the proliferation, migration, and invasion of oral squamous cell carcinoma by directly targeting SATB2.

In various kinds of carcinomas, the special AT-rich sequence-binding protein 2 (SATB2) with its atypical expression promotes the metastasis and progression of the tumor, though in the oral squamous cell carcinoma (OSCC) its inherent mechanism and the status of SATB2 remain unclear. The role played by the SATB2 expression in the OSCC cell lines and tissue samples in the target of miR-34a downstream is the intended endeavor of this study. In te OSCCs the miR-34a expression was determined by quantitative real-time polymerase chain reaction (q-PCR), while the SATB2 expression in the cell lines and tissue samples in OSCC was analyzed with the q-PCR and the western blot. Studies in both in vitro and in vivo of the effects of miR-34a on the initiation of OSCC were conducted. As a direct target of the miR-34a the SATB2 was verified with the luciferase reporter assay. In cases where the miR-34a levels were low, the SATB2 in OSCCs seemed to be overexpressed. Besides, both in the in vitro and in vivo a suppression of migration, invasion, and cell growth was caused by miR-34a by down regulating the SATB2 expression. The SATB2 being a direct target of miR-34a was confirmed by the cotransfection of miR-34a mimics specifically the decrease in the expression of luciferase of SATB2-3'UTR-wt reporter. As a whole, our study confirmed the inhibition of miR-34a in the invasion, proliferation, and migration of the OSCCs, playing a potential tumor suppressor role with SATB2 as its downstream target.

Comparison of patient-centered outcomes after routine implant placement, teeth extraction, and periodontal surgical procedures.

OBJECTIVES: To compare patient-centered outcome assessments (POAs) over a 2-week period after five categories of dento-alveolar surgical procedures. METHODS: A total of 339 patients in need of dento-alveolar surgical procedures such as simple tooth extraction (SE), transalveolar extraction (TE), straightforward implant placement (I), implant placement with guided bone regeneration (IGBR), and periodontal surgery (P) in Hong Kong (51.3%) and Nanjing dental clinic were consecutively recruited (2013-2015). POAs in terms of bleeding, swelling, pain, and bruising were obtained using 10 cm visual analog scale (VAS) on each day of the first week and the 14th day postsurgery. Clinical examinations were recorded on the 7th day postoperation. RESULTS: For the first 3 days of healing, area-under-the-curve (AUC) analyses showed that transalveolar extraction (TE) resulted in significantly higher overall bleeding and pain (AUC: Bleeding Mean = 5.6, Pain Mean = 7.5). However, implant placement with GBR (IGBR) resulted in significant higher level of swelling (AUC: Mean = 9.1) and bruising (Mean = 4.2) for the same period with also the highest use of painkillers. Healing outcomes of straightforward implant placement (I) were comparable to that of a simple extraction (SE). Two-week overall experience showed the symptoms quickly subsided for all groups. Prevalence for complications 1 week postoperatively was IGBR (20%), P (15.6%), I (12.7%), SE (4.8%), TE (1.5%), respectively. CONCLUSIONS: The highest extent of swelling and bruising was observed in patients who got implant placement with GBR (IGBR), while healing events of straightforward implants were similar to these of simple extraction. The VAS scores for all POAs parameters were generally low and decreased to nearly zero over the study period following all five surgical procedures. Low prevalence of postsurgical complications was reported.

Extended Free Forearm Flap for Treatment of Temporomandibular Joint Pseudoankylosis.

Pseudoankylosis of temporomandibular joint (TMJ) is characterized by limited mouth opening and impaired mandibular mobility induced by pathologic factors outside the joint itself, usually leading to compromised speech, swallowing, and breath functions. Multiple surgical approaches or reconstructive procedures have been proposed to resolve the joint pseudoankylosis and restore the mandibular movement for these affected patients. Free forearm flap has been widely used in reconstruction for various congenital or acquired defects or deformities; however, this flap has been rarely employed for TMJ pseudoankylosis in the literature. Here, the authors reported that noma-induced TMJ pseudoankylosis was diagnosed and successfully treated by extended free forearm flap with length over 10 cm in a Chinese female patient.

Brush biopsy with DNA-image cytometry: a useful and noninvasive method for monitoring malignant transformation of potentially malignant oral disorders.

Oral and pharyngeal cancer is the sixth most common cancer worldwide, the 5-year survival rate has not yet increased. A key factor in rates not having improved is the lack of early detection. This study was undertaken to estimate the diagnostic accuracy of brush biopsy with DNA-image cytometry (a noninvasive method) for potentially malignant oral disorders compared with tissue biopsy pathology in China. Exfoliative cells were obtained using a cytobrush cell collector from oral mucosa of 52 subjects, followed by scalpel biopsy from the same region. Nuclear DNA contents (ploidy) were measured after Feulgen restaining, using an automated DNA image cytometer. Exfoliative cytology with DNA-image cytometry and histopathological diagnosis were performed separately at different institutions. Histological investigation was considered the gold standard. We reported that the sensitivity of DNA aneuploidy for the detection of cancer cells in potentially malignant oral disorders was 86.36 %, its specificity was 90.00 %, its positive predictive value was 86.36 %, and its negative predictive value was 90.00 %. Brush biopsy with DNA-image cytometry is a useful method for monitoring potentially malignant oral disorders.

Radial forearm free flap for reconstruction of a large defect after radical ablation of carcinoma of the tongue and floor of the mouth: some new modifications.

BACKGROUND: A modified radial forearm free flap was designed to rehabilitate function and to reduce the complications at both donor and recipient sites. METHODS: Between 2003 and 2007, 15 patients with infiltrating squamous cell carcinoma (T(3)-T(4)) of the tongue and/or floor of the mouth underwent hemiglossectomy and resection of the floor of the mouth with microvascular reconstruction using a modified radial forearm flap. The mean size of the forearm flap was 7.5 x 14 cm, and the de-epithelialized area was 7 x 6 cm, requiring no skin graft from the abdomen. Speech intelligibility tests were administered to test postoperative speech and the functional oral intake scale was applied to assess the postoperative swallowing function, and patients reconstructed with pectoralis major myocutaneous flap were used for comparison. RESULTS: All the flaps were successfully transferred. No obvious complications were found in either the oral-maxillofacial or forearm region. The speech intelligibility was better in the modified flap group (p < 0.01). An acceptable swallowing function was also achieved, although the difference was not significant (p > 0.05). CONCLUSIONS: The modified flap used for reconstructing large defects of the tongue and floor of the mouth might be a valid substitute for pectoralis major myocutaneous flap to improve the outcome in individuals with significant oral carcinoma.

Anatomical study and clinical application of medial sural artery perforator flap for oral cavity reconstruction.

The present study aims to provide anatomical evidence for clinical application of the medial sural artery perforator (MSAP) flap. The current study investigated the vascular anatomy of the flap, evaluated the postoperative appearance and function of the donor and recipient sites, and investigate the clinical value in reconstruction of oral cavity. Six lower limbs of Chinese adult cadavers were microsurgically dissected. The locations and courses of the medial sural artery perforators were identified and recorded, which provided an anatomical basis for clinical application. Then, 16 clinical cases employing this flap were evaluated, ranging from 3×4cm to 6×8cm, and were employed for defects in the oral cavity region. Sixteen clinical cases with intraoral soft tissue defects, which included four clinical cases with inner cheek defects, were successfully followed up for 10-47 months (24 months on average). The donor site function, contour of recipient site and oral function recovery were evaluated as acceptable or better in cases with intraoral soft tissue defect, which were further verifying the value of clinical application of MSAP in repairing oral cavity defects. Moreover, two typical clinical cases were described in detail. To conclude, the MSAP flap is a favorable choice for small- to medium-size defects based on minor donor site morbidity, satisfactory oral function recovery, perforator stability and adaptation of the pedicle for anastomosis in the oral cavity region.

FOXM1 is a novel predictor of recurrence in patients with oral squamous cell carcinoma associated with an increase in epithelial­mesenchymal transition.

Although forkhead box protein M1 (FOXM1) is markedly upregulated in human premalignant and oral squamous cell carcinoma (OSCC) tissues and cultured cells, the association of FOXM1 expression with OSCC prognosis is not well understood. The present study investigated the possible association of FOXM1 expression in patients with OSCC with their clinicopathological characteristics and clinical outcomes. The expression of FOXM1 protein in OSCC tissues from 119 patients was evaluated by immunohistochemistry, and the results demonstrated that FOXM1 overexpression in patients with OSCC was associated with tumour recurrence and poor prognosis. To study the in vitro effects of FOXM1, its expression was decreased by small interfering RNA (siRNA) in OSCC cell lines, and FOXM1 knockdown decreased the proliferative, migratory and invasive capacities of cells. FOXM1 inhibition by siRNA gave rise to reduced expression of vimentin and increased expression of E­cadherin. The present study reported FOXM1 as a novel predictor of tumour recurrence in patients with OSCC and its potential involvement in epithelial­mesenchymal transition in OSCC cells.

Knockdown of MSI1 inhibits the proliferation of human oral squamous cell carcinoma by inactivating STAT3 signaling.

Musashi RNA­binding protein 1 (MSI1) is highly expressed in several types of cancer; however, its role in oral squamous cell carcinoma (OSCC) remains unknown. The purpose of this study was to investigate the probable mechanism underlying the involvement of MSI1 in OSCC. The results demonstrated that MSI1 was upregulated in OSCC tissues, but not in adjacent healthy tissues. MSI1 silencing resulted in decreased cell proliferative, invasive and migrative capacity. In addition, MSI1 silencing led to cell cycle arrest at the S phase, downregulation of c­Myc and cyclin D1, and upregulation of p21 and p27 levels. Additional studies demonstrated that MSI1 suppression inhibited the activation of signal transducer and activator of transcription 3 (STAT3) signaling. Accordingly, the findings of the present study suggested that MSI1 silencing can suppress OSCC cell proliferation and progression, in part by inhibiting the activation of the c­Myc/STAT3 pathway.

Inactivation of RUNX3 protein expression in tongue squamous cell carcinoma and its association with clinicopathological characteristics.

The function of runt­related transcription factor 3 (RUNX3) in oral cancer remains controversial. The present study aimed to determine the status of RUNX3 protein expression and its association with clinicopathological characteristics in tongue squamous cell carcinomas (SCC). The present study used three pairs of tongue SCC and non­cancerous tissues to assess RUNX3 protein expression by western blot analysis, and two tongue SCC cell lines to determine RUNX3 protein localization by immunofluorescence and immunocytochemistry. Tissue microarray immunohistochemistry was performed to detect the clinical relevance of RUNX3 in 79 patients with tongue SCC. The results demonstrated that RUNX3 protein expression was reduced in tongue SCC tissues compared with in paired non­cancerous tissues. Similarly, the expression of RUNX3 was low in SCC25 and Cal27 cells, and was predominantly localized to the cytoplasm. In the 79 patients with tongue SCC, RUNX3 protein expression was presented in different manners in carcinoma nests and tumor stroma. RUNX3 in carcinoma nests (nRUNX3) exhibited nuclear positive staining in 24/79 samples, cytoplasmic mislocalization in 41/79 samples and was undetectable in 14/79 samples. RUNX3 in stroma (sRUNX3) exhibited nuclear positive staining in 40/79 samples and nuclear negative staining in 39/79 samples. Negative nRUNX3 expression was significantly associated with lymph node metastasis (P=0.014), clinical stage (P=0.027), and overall and disease­free survival (P=0.008 and P=0.007, respectively). In addition, negative sRUNX3 expression was associated with lymph node metastasis (P=0.003) and clinical stage (P=0.003); however, not with overall survival. The findings of the present study preliminarily suggested that cytoplasmic mislocalization of RUNX3 protein may be a common event in tongue SCC, and that sRUNX3 protein expression may be a potential prognostic biomarker.

Application of lateral arm free flap in oral and maxillofacial reconstruction following tumor surgery.

OBJECTIVE: To describe the application of lateral arm free flap (LAFF) in reconstruction of defects in the oral and maxillofacial regions following ablative oncological surgery. SUBJECTS AND METHODS: The study included 16 patients (13 male, 3 female, mean age 56, range 35-69 years). Sixteen LAFF were harvested to reconstruct defects caused by the dissection of malignant tumors of the oral and maxillofacial regions. The tumor was squamous cell carcinoma of the tongue (6 cases), floor of the mouth (4), retromolar area (3), inner cheek (2), and lower gingival (1). Flap sizes ranging from 5 x 7 to 6 x 9 cm were harvested using a sterile tourniquet for bloodless technique. The anastomoses were carried out using a magnifier or microscope. All donor defects were closed primarily. RESULTS: Fourteen flaps healed without venous insufficiency. One flap, in a female patient, survived with mild local microcirculatory obstruction but that of another female patient developed necrosis. There was no significant complication at the donor sites. The advantages of this flap include anatomically reliable vascular supply, accessible donor site, and the aesthetic quality of donor tissue is good. Compared with the radial artery, the posterior radial collateral artery is a nonessential vessel of the arm. The disadvantages are the relatively smaller vessel size for anastomosis and thicker subcutaneous tissue. CONCLUSIONS: For the repair of moderate-sized defects of the maxillofacial area, especially in male patients, the LAFF can be recommended.

[Expression and correlation of HPV16E6 and tumor suppressor gene p53 in oral squamous cell carcinoma].

PURPOSE: To exploring the expression of PV16E6 gene and p53 gene in patients with oral carcinoma and the correlation between pathological grade and clinical stage of oral cancer and expression of HPV16E6 gene and p53 gene. METHODS: One hundred and seventy-three cases of oral cancer, 98 cases of oral precancerous lesions and 79 cases of peri-cancerous normal tissue were selected. The expression of HPV16E6 and p53 was detected by immunohistochemistry. The data were analyzed using SPSS 21.0 software package. RESULTS: In oral carcinoma, the expression rate of HPV16E6 was 81.5% (141/173), the expression rate of p53 was 23.7% (41/173); in oral precancerous lesions, the expression rate of HPV16E6 was 39.8% (39/98), the expression rate of p53 was 57.1% (56/98); in peri-cancerous normal tissues, the expression rate of HPV16E6 was 2.5%(2/79), the positive expression rate of p53 was 89.9%(71/79). There was significant difference in the positive expression rate of p53 and HPV16E6 among 3 groups. The expression of HPV16E6 in oral cancer was significantly higher than in the other two groups(P<0.05); the expression rate of p53 in oral cancer was significantly lower than the other two groups. In addition, with the advance of clinical stage and pathological grade, the positive expression rate of HPV16E6 increased gradually, while the positive expression rate of p53 was significantly decreased (P<0.05). CONCLUSIONS: HPV16E6 protein and p53 protein may play an important role in the occurrence and progress of oral cancer.

RUNX3 plays a tumor suppressor role by inhibiting cell migration, invasion and angiogenesis in oral squamous cell carcinoma.

Although aberrant expression of Runt-related transcription factor 3 (RUNX3) contributes to tumor progression and metastasis in a number of carcinomas, the status of RUNX3 and its correlation with prognosis in oral squamous cell carcinomas (OSCC) are still controversial. The aim of present study was to investigate the function of RUNX3 in OSCC and the underlying molecular mechanisms. Tissue microarray (TMA) consisting of 232 OSCC specimens was used to detect the expression of RUNX3 by immunohistochemistry method. The effects of RUNX3 restoration on OSCC cell migration and invasion were determined by wound-healing assay, migration and Matrigel cell invasion assays. The antiangiogenic role of RUNX3 was analyzed by testing proliferation and tube formation of human umbilical vascular endothelial cells (HUVECs) cultured with conditioned medium from RUNX3 transfected OSCC cell lines. The activities of MMP-9 and VEGF in RUNX3 transfected OSCC cell lines were examined by western blot and Elisa methods. RUNX3 expression was reduced in OSCC specimens and significantly associated with tumor size (P=0.002), lymph node statue (P=0.0036) and clinical stage (P=0.0001). Negative expression of RUNX3 correlated with worse 5-year overall and disease-specific survival rates (P=0.0348 and P=0.0301, respectively). Furthermore, we found that RUNX3 restoration suppressed cell migration and invasion through downregulating MMP-9 expression and secretion, and exerted antiangiogenic capability by inhibiting VEGF activity in HN6 and Cal27 cells. These findings suggested that RUNX3 played a tumor suppressor role in OSCC by inhibiting cell migration, invasion and angiogenesis, supporting that it could be a potential therapeutic target for OSCC.

The overexpressed functional transient receptor potential channel TRPM2 in oral squamous cell carcinoma.

TRPM2, one member of the transient receptor potential (TRP) protein super-family, is a Ca2+-permeable channel that is activated by oxidative stress and confers susceptibility to cell death. In the human tongue specimens of carcinoma and the tongue carcinoma SCC cell lines, we observed the enhanced expression of TRPM2. By means of the whole-cell electrophysiological recording, the ADPR-induced currents mediated by TRPM2 were recorded in cultured SCC9 cells. Moreover, after H2O2 treatment for 24 hours, the apoptotic number of SCC9 cells was significantly increased. However, the selectively knocked-down TRPM2 with the small interfering RNA technique inhibited the survival and migration of the SCC9 cancer cells, which was independent of the p53-p21 pathway, since the expression of p21 was enhanced after TRPM2 knockdown. Furthermore, the sub-cellular localization of TRPM2 was remarkably different between cancerous and non-cancerous cells. A significant amount of the TRPM2 proteins were located in the nuclei in cancer cells. All these data suggest that TRPM2 is essential for the survival and migration of SCC cancer cells and may be a potential target for the selective treatment of tongue cancer.

Tumor-associated macrophages correlate with the clinicopathological features and poor outcomes via inducing epithelial to mesenchymal transition in oral squamous cell carcinoma.

BACKGROUND: Both tumor-associated macrophages (TAMs) and the epithelial to mesenchymal transition (EMT) of cancer cells play key roles in promoting tumor progression. However, whether TAMs could induce EMT in the progression of oral squamous cell carcinoma (OSCC) remains undefined. RESULTS: Here we detected the expression of macrophages markers CD68 and CD163, epithelial marker E-cadherin and mesenchymal marker vimentin in 127 OSCC patients by using semi-quantitative immunohistochemistry. CD68 and CD163 expression was not confined to the infiltrating TAMs, but also detected in cancer cells. The high number of CD68-positive macrophages was correlated with poor overall survival. Meanwhile, the expression of CD163 both in macrophages and in cancer cells was associated with poor overall survival and had a significant prognostic impact in OSCC. Importantly, the expression of CD163 in cancer cells had a significant relationship with E-cadherin and vimentin. Furthermore, the incubation of TAMs conditioned medium resulted in a fibroblast-like appearance of cancer cells (HN4, HN6 and SCC9) together with the decreased/increased expression of E-cadherin/ vimentin, which were correlated with the enhanced ability of migration and invasion. CONCLUSIONS: Our results indicate that TAMs could promote the EMT of cancer cells, thereby leading to the progression of oral cancer.

Interleukin-1ß (3953/4) C→T polymorphism increases the risk of chronic periodontitis in Asians: evidence from a meta-analysis of 20 case-control studies.

INTRODUCTION: To investigate the association of the interleukin-1ß (IL-1ß) (3953/4) C→T polymorphism with chronic periodontitis (CP) in Asians. MATERIAL AND METHODS: Systematic searches of electronic databases and hand searching of references were performed, including PubMed, Embase, the Cochrane Library, and the Chinese National Knowledge Infrastructure (CNKI). Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of the associations. Publication bias was tested by Egger's test. Sensitivity analysis was conducted by limiting the meta-analysis studies conforming to Hardy-Weinberg equilibrium (HWE). Data analyses were carried out using RevMan 6.0. RESULTS: A meta-analysis was performed on 20 published case-control studies, including 1,656 CP cases and 1,498 healthy controls. The pooled OR was 1.60 (95% CI = 1.02-2.52, p = 0.04) for the T allele carriers (TT + CT) compared with CC and 1.60 (95% CI = 1.06-2.42, p = 0.02) for T vs. C. Subgroup analysis by country revealed significant risks of CP among Indians carrying the T allele (TT vs. CC: OR = 3.88, 95% CI = 1.77-8.50, p = 0.0007). CONCLUSIONS: The analysis showed that IL-1ß (3953/4) C→T polymorphism probably increases the risk of CP in Asians, and the IL-1ß+3954 TT genotype may be associated with a strongly increased risk of CP in Indians, but not in Chinese.

The Pin1 gene polymorphism and the susceptibility of oral squamous cell carcinoma in East China.

Pin1 is a peptidylprolyl isomerase that specifically recognizes phosphorylated Pro-directed Ser/Thr (pSer/Thr-Pro) peptide sequences. Genetic variants in the Pin1 gene may alter protein function and cancer risk. In this study, we genotyped the two common promoter polymorphisms -842G/C (rs2233678) and -667T/C (rs2233679) in two independent hospital-based case-control studies conducted in Eastern Chinese populations, including 209 patients with oral squamous cell carcinoma and 444 cancer-free controls. We found -667TT heterozygotes had a significantly increased risk of oral squamous cell carcinoma (P=0.028, OR=1.66, 95%CI=1.02-2.69). However, there was no risk significant associated with the -842G/C polymorphism. Further large population-based studies are needed to confirm these results.

[The influence of drilling pulling ways and cooling systems on dental implant surgery].

PURPOSE: To study the effect of different ways of pulling the drilling burs and cooling systems on alveolar bone temperature of the surgical area, and explore the changes of temperature field in dental implants. METHODS: Forty-eight unified standard artificial (nylon) bone blocks were fabricated and divided into 6 groups according to different drilling pulling ways and cooling systems. The changes of bone temperature field were detected in 6 groups, and the highest temperature in temperature field was measured and recorded. The date was analyzed with SPSS 12.0 software package for ANOVA. RESULTS: The temperature in the surgical area using internal cooling systems under the same drilling pulling was lower than using external cooling systems. The temperature in the surgical area using secondary drilling pulling way was lower than using direct drilling methods under the same cooling systems. The temperature in the surgical area using secondary drilling pulling way was the lowest when internal cooling systems was adopted(P<0.05). CONCLUSIONS: Drilling pulling way and internal cooling systems can effectively reduce the temperature in the surgical area, lessen heat production and improve the success rate of dental implants.

[Clinical effect of functional repair of bilateral cleft lip in 66 patients].

PURPOSE: To explore the clinical effect of functional repair for bilateral cleft lip using modified Mulliken method. METHODS: Sixty-six patients with bilateral cleft lip were selected and assigned to receive modified Mulliken method. During the operation, the prolabium was kept as narrow "tie" shape, the orbicularis oris was anatomically repositioned, and the orbicularis oris ring was re-built. Vermilion tubercle was reconstructed with the lateral red vermillion. The nasal deformity was preliminarily repaired. and the nasal columella was elongated at the same time. RESULTS: All the patients were followed-up for 0.5-2 years, there was no "trisection upper lip". The symmetry and natural shape of Cupid's bow were obtained in more than 80% patients. The width of philtrum was similar to normal children. Full vermilion of the lips, moderate-size vermilion tubercles and good dynamic and static shape were obtained without whistle deformities. Normal width of nasal base and nostril symmetry were gained. The columella was elongated. Satisfactory contour of the nasal tip was achieved. CONCLUSIONS: Modified Mulliken method could functionally repair bilateral cleft lip and effectively correct nasolabial deformities. It is worthy of wide clinical application.

Monocarboxylate transporter 4 facilitates cell proliferation and migration and is associated with poor prognosis in oral squamous cell carcinoma patients.

Monocarboxylate transporter 4 (MCT4) is a cell membrane transporter of lactate. Recent studies have shown that MCT4 is over-expressed in various cancers; however, its role in cancer maintenance and aggressiveness has not been fully demonstrated. This study investigated the role of MCT4 in oral squamous cell carcinoma (OSCC), and found that it is highly expressed in OSCC patients by using immunohistochemistry. Moreover, this over-expression of MCT4 was closely associated with tumor size, TNM classification, lymphatic metastasis, distant metastasis and tumor recurrence, and also poor prognosis. To further study mechanisms of MCT4 in vitro, we used small-interfering RNA to silence its expression in OSCC cell lines. The results showed that knock-down of MCT4 decreased cell proliferation, migration, and invasion. The inhibition of proliferation was associated with down-regulation of p-AKT and p-ERK1/2, while decreased cell migration and invasion may be caused by down-regulation of integrin ß4-SRC-FAK and MEK-ERK signaling. Together, these findings provide new insight into the critical role of MCT4 in cell proliferation and metastasis in OSCC.

Contactin 1 (CNTN1) expression associates with regional lymph node metastasis and is a novel predictor of prognosis in patients with oral squamous cell carcinoma.

The contactin 1 (CNTN1) gene exerts oncogene­like activities and its expression has been linked to several human malignancies. In this study, a possible association between CNTN1 expression and clinicopathological parameters and clinical outcomes in patients with oral squamous cell carcinoma (OSCC) was examined. CNTN1 protein expression was evaluated by immunohistochemistry in OSCC tissues of 45 patients. For the immunohistochemical assessment of CNTN1 expression, the cytoplasmic staining labeling index was analyzed using a semiquantitative score. The association between CNTN1 protein levels and clinicopathological factors was analyzed using the Mann-Whitney U test for categorical variables and the Kruskal-Wallis test for continuous variables. The effects of CNTN1 expression on overall and disease-free survival were assessed by using univariate survival analysis. The transcript levels of CNTN1 were detected in OSCC cell lines. In addition, specific siRNA against CNTN1 was applied to investigate the effect exerted by CNTN1 ablation on OSCC cell lines by proliferation and invasion assays in vitro. During follow-up, 16 patients (35.56%) had succumbed to OSCC; the median follow-up of patients was 5.0 years (range, 0.2-8.3). A high expression of CNTN1 was markedly associated with the regional lymph node metastasis of patients with OSCC (P=0.006). CNTN1 expression was significantly associated with overall survival of patients with OSCC (P=0.032; log-rank test) and disease-free survival of patients with OSCC (P=0.038; log-rank test). In addition, CNTN1 ablation notably suppressed the invasion potential of OSCC cell lines, but there was no significant change in the proliferation of OSCC cell lines by CNTN1 knockdown in vitro. The study supports CNTN1 as a novel predictor of regional lymph node metastasis in patients with OSCC and a prognostic marker for OSCC in patients.