MYCT1 inhibits hematopoiesis in diffuse large B-cell lymphoma by suppressing RUNX1 transcription.

BACKGROUND: The abnormality of chromosomal karyotype is one factor causing poor prognosis of lymphoma. In the analysis of abnormal karyotype of lymphoma patients, three smallest overlap regions were found, in which MYCT1 was located. MYCT1 is the first tumor suppressor gene cloned by our research team, but its studies relating to the occurrence and development of lymphoma have not been reported. METHODS: R banding analyses were employed to screen the abnormality of chromosomal karyotype in clinical specimen and MYCT1 over-expression cell lines. FISH was to monitor MYCT1 copy number aberration. RT-PCR and Western blot were to detect the mRNA and protein levels of the MYCT1 and RUNX1 genes, respectively. The MYCT1 and RUNX1 protein levels in clinical specimen were evaluated by immunohistochemical DAB staining. The interaction between MYCT1 and MAX proteins was identified via Co-IP and IF. The binding of MAX on the promoter of the RUNX1 gene was detected by ChIP and Dual-luciferase reporter assay, respectively. Flow cytometry and CCK-8 assay were to explore the effects of MYCT1 and RUNX1 on the cell cycle and proliferation, respectively. RESULTS: MYCT1 was located in one of three smallest overlap regions of diffuse large B-cell lymphoma, it altered chromosomal instability of diffuse large B-cell lymphoma cells. MYCT1 negatively correlated with RUNX1 in lymphoma tissues of the patients. MAX directly promoted the RUNX1 gene transcription by binding to its promoter region. MYCT1 may represses RUNX1 transcription by binding MAX in diffuse large B-cell lymphoma cells. MYCT1 binding to MAX probably suppressed RUNX1 transcription, leading to the inhibition of proliferation and cell cycle of the diffuse large B-cell lymphoma cells. CONCLUSION: This study finds that there is a MYCT1-MAX-RUNX1 signaling pathway in diffuse large B-cell lymphoma. And the study provides clues and basis for the in-depth studies of MYCT1 in the diagnosis, treatment and prognosis of lymphoma.

Overexpression of hsa-miR-125a-5p enhances proliferation, migration and invasion of head and neck squamous cell carcinoma cell lines by upregulating C-C chemokine receptor type 7.

Head and neck squamous cell carcinoma (HNSCC) is usually diagnosed accompanied by lymph node metastasis. C-C chemokine receptor type 7 (CCR7) is associated with the invasion and metastasis of tumors in HNSCC through various signaling pathways. The role of hsa-miR-125a-5p in HNSCC remains unclear. The present study was performed to investigate the association between hsa-miR-125a-5p and CCR7 in HNSCC. Reverse transcription-quantitative polymerase chain reaction was applied to analyze the expression of hsa-miR-125a-5p in clinical samples. Cell Counting Kit-8, Transwell and wound healing assays were used to detect cell proliferation, invasion, and metastasis, respectively, following overexpression of hsa-miR-125a-5p. Changes in protein expression of CCR7 were observed using western blotting. In the survival analysis, Student's t-tests and log rank tests were performed to analyze the association between the expression of hsa-miR-125a-5p, and HNSCC according to the Cancer Genome Atlas database. The expression of hsa-miR-125a-5p was identified to be significantly lower in cancer tissue compared with the corresponding adjacent normal tissues in clinical samples (P=0.038). The results of western blotting indicated that there was a positive regulatory association between hsa-miR-125a-5p and CCR7. Furthermore, overexpression of hsa-miR-125a-5p significantly enhanced the ability of cell proliferation, migration and invasion in HNSCC, with upregulation of CCR7. The results of survival analysis revealed that patients in the low expression group of hsa-miR-125a-5p tended to have longer survival times compared with the high expression group (P=0.045). Altogether, the data raised the possibility that hsa-miR-125a-5p has a significant role in promoting cancer in HNSCC, which may provide a basis for the treatment of HNSCC in molecular targeted therapy. Further studies are required to ascertain the role of hsa-miR-125a-5p in other HNSCC cell lines and in vivo.

The role of Pyk2 in the CCR7-mediated regulation of metastasis and viability in squamous cell carcinoma of the head and neck cells in vivo and in vitro.

In the present study, we aimed to demonstrate whether praline-rich tyrosine kinase-2 (Pyk2) participates in the chemokine receptor 7 (CCR7) downstream signaling network, and to determine the role of this molecule and the related mechanism in the CCR7-mediated regulation of viability and metastasis in vivo and in vitro of squamous cell carcinoma of the head and neck (SCCHN). We constructed the stable Pyk2 related non-kinase (PRNK)-expressing SCCHN cell line, and examined the viability, apoptosis, migration, invasion and adhesion ability in the transfected and untransfected SCCHN cells. An SCCHN tumor model in nude mice was designed and the tumor growth rate was assayed. E-cadherin and vimentin expression was assessed when Pyk2 was inactivated. We found that the stable PRNK-expressing SCCHN cells exhibited low viability, a high rate of apoptosis, low migratory ability, low invasive ability and low adhesion capacity. In the nude mouse body, the tumors formed by these cells grew slowly when compared to the tumor growth in the control group. When Pyk2 was inactivated, CCR7-induced E-cadherin and vimentin expression levels were altered. Thus, Pyk2 is a key downstream signaling molecules of CCR7 in SCCHN, which promotes SCCHN tumorigenesis and progression.

CCR7 regulates cell migration and invasion through JAK2/STAT3 in metastatic squamous cell carcinoma of the head and neck.

Squamous cell carcinoma of the head and neck (SCCHN) frequently involves metastasis at diagnosis. Our previous research has demonstrated that CCR7 plays a key role in regulating SCCHN metastasis, and this process involves several molecules, such as PI3K/cdc42, pyk2, and Src. In this study, the goals are to identify whether JAK2/STAT3 also participates in CCR7's signal network, its relationship with other signal pathways, and its role in SCCHN cell invasion and migration. The results showed that stimulation of CCL19 could induce JAK2/STAT3 phosphorylation, which can be blocked by Src and pyk2 inhibitors. After activation, STAT3 was able to promote low expression of E-cadherin and had no effect on vimentin. This JAk2/STAT3 pathway not only mediated CCR7-induced cell migration but also mediated invasion speed. The immunohistochemistry results also showed that the phosphorylation of STAT3 was correlated with CCR7 expression in SCCHN, and CCR7 and STAT3 phosphorylation were all associated with lymph node metastasis. In conclusion, JAk2/STAT3 plays a key role in CCR7 regulating SCCHN metastasis.

CCR7 regulates cell migration and invasion through MAPKs in metastatic squamous cell carcinoma of head and neck.

Migration and invasion of tumor cells are essential prerequisites for the formation of metastasis in malignant diseases. Previously, we have reported that CC chemokine receptor 7 (CCR7) regulates the mobility of squamous cell carcinoma of head and neck (SCCHN) cells through several pathways, such as integrin and cdc42. In this study, we investigated the connection between CCR7 and mitogen-activated protein kinase (MAPK) family members, and their influence on cell invasion and migration in metastatic SCCHN cells. Western blotting, immunostaining and fluorescence microcopy were used to detect the protein expression and distribution of MAPKs, and the Migration assay, Matrigel invasion assay and wound-healing assay to detect the role of MAPKs in CCR7 regulating cell mobility. To analyze the correlation between CCR7 and MAPK activity and clinicopathological factors immunohistochemical staining was emplyed. The results showed stimulation of CCL19 and the activation of CCR7 could induce ERK1/2 and JNK phosphorylation, while it had no efect on p38. After activation, ERK1/2 and JNK promoted E-cadherin low expression and Vimentin high expression. The MAPK pathway not only mediated CCR7 induced cell migration, but also mediated invasion speed. The immunohistochemistry results showed that CCR7 was correlated with the phosphorylation of ERK1/2 and JNK in SCCHN, and these molecules were all associated with lymph node metastasis. Therefore, our study demonstrates that MAPK members (ERK1/2 and JNK) play a key role in CCR7 regulating SCCHN metastasis.

Submental versus platysma flap for the reconstruction of complex facial defects following resection of head and neck tumors.

OBJECTIVE: To compare the platysma flap with submental flap in terms of tumor and flap characteristics, operative properties and the functional outcomes. METHODS: A total of 65 patients presented with tumors of head and neck and underwent curative tumor resection with different neck dissections at the Department of Oromaxillofacial-Head and Neck Surgery, School of Stomatology of China Medical University; from March 2005 to December 2012 were included in the study. After radical tumor excision and neck dissection the resultant complex defects were reconstructed with either platysma flap or the submental flap. The extent of surgical resection, the type of neck dissection and choice of flap reconstruction was at the discretion of the surgical team. The functional outcomes, operative time and characteristics of both platysma and submental flaps were compared and the statistical tests of significance were applied accordingly. RESULTS: The mean age was 60 years. The complex facial defects of 30 patients were reconstructed with platysma flap and of 35 patients with submental flap. Mean operation time of submental flap including flap harvesting (5.58±1.96hrs) was shorter than platysma flap (6.2±1.4hrs). The majority of the flaps (88-93%) were taken successfully in both groups. Submental flap was associated with significantly higher patients' satisfaction regarding acceptable functional outcomes (p-value 0.027). The mean reduction in mouth opening was significantly smaller in platysma group (0.37 ±0.18cms) than the submental group (0.47±0.16). CONCLUSION: This study demonstrates that both platysma and submental flap techniques can be used for the reconstruction of complex facial defects with the acceptable functional outcome. The platysma flap can be harvested to medium size defects up to 70cm(2) with good mouth opening. The submental flap is simpler, faster with a wider range of application and more acceptable functional outcomes.

Total lower lip reconstruction with a double mental neurovascular V-Y island advancement flap.

PURPOSE: To assess the effectiveness of double mental V-Y island advancement flaps for total lower lip reconstructions. MATERIALS AND METHODS: During a 6-year period, from 2006 to 2012, total lower lip reconstruction was performed in 12 patients using double mental V-Y island advanced flaps. The resulting lip function and superiority of each flap were analyzed. To assess any cosmetic implications, patients were asked to answer the Appearance Domain section from the University of Washington Quality of Life Questionnaire at least 12 months after discharge from the hospital. RESULTS: All flaps survived completely and no short-term postoperative complications occurred. The mean follow-up time was 34.5 months (range, 15 to 69 months) and there was no recurrence of disease. All patients were capable of consuming a regular oral diet and no patients complained of an inability to eat in a public setting, drooling, or microstomia. The mean preoperative and postoperative open-mouth widths were 4.1 and 3.7 cm, respectively, and the mean reduced open-mouth width was 10%. The intercommissural width varied from 4.6 to 6.8 cm (mean, 5.5 cm). The mean postoperative 2-point discrimination was 11.2 mm (range, 9 to 13 mm). The mean score for the Appearance Domain section was 93.8 (range, 75 to 100). CONCLUSION: The mental V-Y island advancement flap reconstruction is a reliable procedure for total lower lip reconstruction.

Upper extremity morbidity after radial forearm flap harvest: a prospective study.

OBJECTIVE: To determine the effect of radial forearm free (RFF) flap harvest on patient-reported postoperative upper extremity disability. METHODS: Patients undergoing RFF flap reconstruction following resection of head and neck cancer were recruited and matched with similar patients undergoing non-RFF reconstruction. All subjects completed the Disability of the Arm, Shoulder, and Hand (DASH) questionnaire preoperatively and at least 1 year postoperatively. RESULTS: Postoperative DASH scores were significantly higher (more severe disability) in patients undergoing RFF flap reconstruction (6.93 ± 5.54; n = 52) compared with those undergoing non-RFF flap surgeries (2.95 ± 4.42; n = 52). Preoperative DASH score, flap size, patient age and tumour stage were significantly correlated with postoperative DASH score. CONCLUSION: Excluding the effect of neck dissection, RFF flap reconstruction has a significant deleterious effect on upper extremity function.

Free fibula flap: assessment of quality of life of patients with head and neck cancer who have had defects reconstructed.

This study investigated the quality of life (QoL) of patients with head and neck cancer undergoing immediate reconstruction of the mandible with free fibula flap. From March 2006 to January 2011, the QoL of 42 patients was assessed using the Medical Outcomes Study Short Form 36 and the University of Washington QoL (version 4) questionnaires. The assessments were performed at least 24 months after surgery. A total of 31 of the 42 questionnaires (73.8%) were returned. The length of harvested fibula varied from 17.5 to 26.1 cm. In the Short Form 36, the lowest-scoring domain was vitality, whereas the highest scores occurred in physical role. According to the University of Washington QoL, the key domains affected by surgery are chewing, speech, and appearance. The domain of pain has the best score. There was a significant effect on the QoL of patients with head and neck cancer with resections of the mandible who had undergone free fibula flap reconstruction. Data from this study may provide useful information for physicians and patients, which may be of value during discussion of treatment modalities for head and neck cancers.

Quality of life in patients younger than 40 years treated for anterior tongue squamous cell carcinoma.

This study investigated the quality of life in patients younger than 40 years with tongue squamous cell carcinoma. We used the University of Washington Head and Neck Quality of Life scale to compare the quality of life outcomes between young and old patients. Cases were patients younger than 40 years who were treated for anterior tongue squamous cell carcinoma. Controls were patients older than 40 years who were matched to the cases regarding diagnosis, sex, and TNM classification. Two controls were matched for each case; thus, 21 cases and 42 controls were selected. Twenty-one of 33 questionnaires (63.6%) were returned. The median follow-up duration was 3.7 years (range, 1-12 y). In the group of young patients, the best-scoring domains were pain, chewing, and swallowing, whereas the lowest scores were for appearance, mood, and anxiety. Young patients (40 years or younger) reported better function, notably regarding activity, recreation, shoulder, taste, and saliva compared with the old patients with anterior tongue squamous cell carcinoma. The patients younger than 40 years tend to have a good quality of life. Most of them were not significantly affected by pain. Quality of life should be used as part of our treatment of anterior tongue squamous cell carcinoma.

Assessment of the quality of life of patients with oral cancer after pectoralis major myocutaneous flap reconstruction with a focus on speech.

PURPOSE: The aim of the present study was to evaluate the quality of life (QoL) of patients with oral cancer who had undergone resection of the tongue and floor of the mouth and reconstruction with the pectoralis major flap. MATERIALS AND METHODS: The present study assessed 21 patients who had undergone pectoralis major flap reconstruction using the University of Washington QoL, version 4, questionnaire. A nonparametric Mann-Whitney U test was used to analyze the data. RESULTS: Of the 12 disease-specific domains, the best 3 scores from the patients were for pain, saliva, and anxiety, and the worst 3 scores were for taste, chewing, and swallowing. The mean UW-QoL composite score was 73.4. Swallowing was considered to be the most important issue within the previous 7 days, followed by chewing and speech. Those patients who had undergone wider excision had poorer speech. CONCLUSIONS: A significant effect was found on the QoL of patients with oral cancer who had undergone resection of the tongue and floor of the mouth with pectoralis major flap reconstruction.

Modified incision design for submental flap: an excellent design method for the reconstruction of a defect after head and neck tumor resection.

BACKGROUND: The usage of submental flap is a good method for head and neck reconstruction, but it has some risk also, such as anatomical variations and surgical errors. In this article, we present a modified incision design for the submental flap. METHODS: We designed a modified submental flap incision method based on the overlap of the incision outline of the submental flap, platysma myocutaneous flap and infrahyoid myocutaneous flap. If we found that the submental flap was unreliable during the neck dissection at the level III, II and Ib areas, the infrahyoid myocutaneous flap or platysma myocutaneous flap was used to replace it. Between 2004 and 2012, we performed 30 cases using this method. As control, 33 radial forearm free flaps were counted. Significant differences were evaluated using the χ(2) test and Mann-Whitney U. Survival and recurrence were analyzed using the Kaplan-Meier method. RESULTS: Of the 30 patients, 27 finally received a submental flap, 1 patient received an infrahyoid myocutaneous flap, and 2 patients received a platysma myocutaneous flap. In patients who received the submental flap, the average operation time was 5.9 hours, 2.4 hours shorter than the radial forearm free flap group; the average age was 61.8, 6.1 years older than the radial forearm free flap group; the survival time and recurrence time did not significantly differ with those of the forearm free flap group; and the success rate was higher than traditional methods. CONCLUSIONS: The wider indications, less required time, the similar low risk of recurrence and death as radial forearm free flap, higher success rate than traditional submental flap harvest methods, and ability to safely harvest a submental flap make the modified incision design a reliable method.

Comparison studies of different flaps for reconstruction of buccal defects.

Our purpose was to evaluate the feasibility of radial forearm free (RFF) flap, platysma myocutaneous (PM) flap, and anterolateral thigh (ALT) flap in buccal reconstruction. This study consisted of 56 patients who were categorized into 3 groups. The Student t test was used to analyze the variables. Patients in group platysma flap were significantly older, the dissection of platysma flap was easier, and the defect was significantly smaller than those in group radial forearm flap and group ALT flap. The reduction in the widths of mouth opening between group PM, group RFF, and group ALT were compared. However, the reduction of mouth-opening widths in group RFF and group ALT was significantly less than that in group PM. Platysma myocutaneous flap may be more suitable in patients with small to middle-size defect and poor status, although the flap cannot achieve a reliable result; anterolateral thigh flap and radial forearm flap can preserve the interincisal distance well even for large buccal defect, but it takes more time and skills in the operation.

Yu's flap for lower lip and reverse Yu's flap for upper lip reconstruction: 20 years experience.

Reconstruction of defects of the lip caused by cancer with its requirements of a complicated anatomical structure, important physiological function, and acceptable cosmetic result, is a challenge for oral and maxillofacial and plastic surgeons. A method that combines rotation and advancement flaps was described by Yu in 1989 for the reconstruction of defects of the lower lip. In our department between January 1992 and December 2012, 8 patients had reverse Yu flaps for the reconstruction of upper lip defects and 56 patients had classic Yu flaps for lower lip defects. Patients with defects located laterally to the upper lips, ranging from ⅓ to ½, had unilateral reverse Yu flaps, and bilateral procedures were done for defects of less than ⅔ of the lips. However, if the defects were located in the centre of the upper lips, between ⅓ and ½, they were treated with bilateral reverse Yu flaps. Patients with defects between ⅓ and ⅔ of lower lips had unilateral Yu flaps, and if the defects were wider than ⅔ of the lower lips, the procedure was bilateral. No flap failed and desirable functional and aesthetic outcomes were recorded in all cases. Here we report our experience with the Yu flap for the benefit of other surgeons.

Vertical platysma myocutaneous flap that sacrifices the facial artery and vein.

BACKGROUND: Platysma myocutaneous flap (PMF) is a generally used technique for defect reconstruction after an oral cancer resection. The aim of the study is to present our experience using vertical PMF that sacrificed the facial artery and vein for intraoral reconstruction. METHODS: A retrospective review of the medical records of 54 patients who underwent vertical PMF that sacrificed the facial artery and vein for intraoral reconstruction was performed. A comparison between PMF that sacrificed and that preserved the facial vessels was made, and we also compared PMF that sacrificed the facial vessels with radial forearm free flap (RFFF). Statistics concerning the patients' clinical factors were gathered. RESULTS: The mean age of the 54 patients who underwent PMF that sacrificed the facial artery and vein was 62.0 ± 10.98 years. The co-morbid disease rate of PMF was 53.7%. The flap size ranged from 12 × 5.5 cm to 7 × 5 cm. Survival of the flap was found in all of the cases, with partial necrosis in four cases (7.4%) and total loss in none of the cases. The operation time was 5.7 ± 1.17 h. The complication and success rates were 27.8% and 92.6%, respectively. The 3-year and 5-year survival rates were 77.8% (21/27) and 69.23% (9/13), respectively. The majority of the patients (87.0%) in our series were satisfied with the results of the surgery. There was no significant difference between PMF that sacrificed or that preserved the facial vessels, both in success rate (P = 1) or complication rate (P = 0.72). The patients in the PMF group were older than the patients in the RFFF group (P = 0.011), the operation time was shorter (P < 0.001), and the co-morbid disease rate was higher (P = 0.002). Although the complication rate of PMF (15/54, 27.8%) was higher than that of RFFF (2/34, 5.9%) (P = 0.011), their success rates were similar (92.6%, 94.1%) (P = 1.00). CONCLUSIONS: Vertical PMF that sacrifices the facial artery and vein has specific advantages including in ease preparation and limitations. This technique may provide an effective method for intraoral reconstruction. Our experience in handling the flap may contribute to the success rate.

Epithelial salivary gland tumors in children: a twenty-five-year experience of 122 patients.

OBJECTIVE: The purpose of this study was to evaluate our 25-year experience of pediatric salivary tumors. METHODS: Patients less than 19 years old with a diagnosis of salivary tumor were identified at Oral-maxillofacial Head and Neck Tumor Center, China Medical University from 1987 to 2011. RESULTS: 122 patients were included in our study, 105 tumors were benign and 17 were malignant. The most common involved site was parotid gland, pleomorphic adenoma represented 91.4% in benign group, and mucoepidermoid carcinoma represented 47.1% in malignant group. All tumors in submandibular gland were benign. Warthin's tumor was diagnosed in one patient. In our follow-up, no regional recurrences occurred in patients without neck dissection. The 5- and 10-year overall survival rates of patients with malignant salivary tumors were 81.8% and 66.7% respectively. CONCLUSIONS: Epithelial salivary tumor was rare, parotid gland was most common involved site, pleomorphic adenoma and mucoepidermoid carcinoma were the most common benign and malignant tumor respectively. The prognosis of patients with malignant salivary tumors was not very favorable.

Clinical reliability of radial forearm free flap in repair of buccal defects.

BACKGROUND: The ideal method for buccal defects should provide good outcome of both function and appearance; our goal is to highlight the reliability of radial forearm flap in buccal reconstruction. METHODS: A retrospective study was conducted. From 2005 to 2012, 20 radial forearm flaps were used to repair the defects. We analyzed the superiority and reliability of the flap; in addition, we reviewed some related literature and made a comparison between radial forearm flap and platysma flap. RESULTS: All radial forearm flaps totally survived, but two flaps suffered venous obstruction, hematoma, respectively. Radial forearm flap preserved the original interincisal distance well. In our follow-up, all patients had sufficient mouth-opening width (mean: 4.3 cm). CONCLUSION: Radial forearm flap is a reliable method for buccal defect reconstruction.

Squamous cell carcinoma of the buccal mucosa: Analysis of clinical presentation, outcome and prognostic factors.

Squamous cell carcinoma (SCC) of the buccal mucosa is a common malignancy in Southeast Asia. The purpose of this study was to present our clinical experience with buccal SCC over a period of 7 years and to analyze the factors associated with surgical outcome. We conducted a retrospective review on 67 buccal SCC patients (between September, 2005 and May, 2011) with tumors restricted to or originating from the buccal mucosa. In a univariate model, nodal stage, degree of tumor differentiation and composite resection were associated with recurrence, while in a multivariate model, the degree of differentiation was the only factor affecting locoregional control. In a survival analysis, recurrence, nodal stage and degree of differentiation were considered as significant factors. Buccal SCC is an aggressive malignant tumor and the degree of differentiation is the most significant factor affecting prognosis and survival. An adequate systemic treatment is required in the case of poorly differentiated tumors. Neck dissection (ND) exerts a positive effect on the locoregional control of buccal SCC staged as cT1-2N0. In the case of identification of positive lymph nodes during surgery, postoperative radiation is recommended in order to improve locoregional control.