Evaluating the Personal Narrative Skills of Monolingual Turkish-Speaking 7- and 10-Year-Old Children with Typical Development through Global TALES: A Pilot Study.

INTRODUCTION: Studies on personal narratives are rare in Turkey and there is no standard protocol for eliciting them. The aim of this small-scale study was to translate the Global TALES Protocol into Turkish, with cultural adaptations, and to present the results regarding its usability for two different age-groups of 7- and 10-year-old school children. We investigated narrative skills in terms of verbal productivity (number of utterances, total number of words), syntactic complexity (mean length of utterance), and semantic diversity (number of different words). In addition, group comparisons were made in terms of the participants' gender and age. METHODS: A total of 20 children, 10 from each age-group (7;0-7;11 and 10;0-10;11) participated in the study. All children were monolingual Turkish-speaking children with typical development. Participants were recruited through personal and/or social networks. All personal narratives were gathered via online connections (Zoom). RESULTS: Descriptive statistics were used to describe the children's performance, and the analysis of group differences was made separately according to age and gender. All children produced narratives in response to the six protocol prompts. In addition, the number of children who did not require the scripted follow-up prompts was higher than those needing a scripted follow-up prompt to produce a response. No statistically significant group differences were found in terms of gender and age on any of the measurements. CONCLUSION: The results from this small-scale investigation showed that the translated version of the Global TALES Protocol was effective in eliciting personal narratives from Turkish-speaking children. We concluded that there is no need to change the directions or give additional guidance or prompts to the children. Future studies with larger samples are needed to confirm these findings.

A case report of synchronous bilateral tonsillar carcinoma associated with human papilloma virus.

The case of a 69-year-old man with bilateral synchronous tonsillar carcinoma is reported. The patient complained of nasal closure, strange voice, and discomfort in his pharynx when he was admitted to the Department of Otolaryngology Head and Neck Surgery at Wakayama Medical University, Wakayama, Japan, in March 2017. The palatine tonsils were enlarged and the surface was irregular. Left cervical lymphadenopathy was also evident. Histological examination from both tonsils was performed and bilateral tonsillar squamous cell carcinoma was diagnosed. PCR analysis showed the same HPV-DNA pattern from bilateral tonsils. Concurrent chemoradiotherapy was performed. Total 70 Gy of irradiation (2Gy/day×35 day) was applied to bilateral tonsillar tumours and upper neck. Follow up was conducted every three months and the patient was free of recurrence for three years. Patient's informed consent was taken to publish the case report.

Functional analysis of ESM1 by siRNA knockdown in primary and metastatic head and neck cancer cells.

BACKGROUND: Genetic factors play a large role in cancer, and thus, there is a great desire to understand the effects of different genes in cancer and to also develop gene therapy for better treatments. Therefore, the development of alternative diagnosis and therapy modalities is of utmost importance. The aim of our study was to illuminate the role of ESM1 (endothelial cell-specific molecule-1, also known as Endocan) in proliferation and migration of head and neck cancer, thus helping to pave the way for new treatment modalities and predictive biomarkers. METHODS: ESM1 expression was shown with immunofluorescence assay using confocal laser scanning microscope in primary and metastatic head and neck cancer cells. ESM1 expression was knocked down by RNA interference in head and neck cancer cells. Knockdown efficiency was evaluated by quantitative real-time RT-PCR and Western blot. Cell proliferation and migration assays were performed by xCELLigence real-time cell analysis system. RESULTS: Immunofluorescence assay showed nuclear localization and high expression of ESM1 in primary and metastatic head and neck cancer cells. ESM1 mRNA and protein levels were significantly decreased in ESM1-knockdown cells compared to control. ESM1-knockdown cells showed reduced proliferation and migration activity when compared to control cells. CONCLUSION: These findings suggest that ESM1 has roles on proliferation and migration of head and neck cancer cells.

Investigation of MACC1 Gene Expression in Head and Neck Cancer and Cancer Stem Cells.

PURPOSE: By investigating the MACC1 gene (metastasis-associated in colon cancer 1) in cancer stem cells (CSC) resistant to chemotherapy and in cancer stem cells (CSC) resistant to chemotherapy and in cancer cells (CS) sensitive to chemotherapy we determineda steady expression in both types of cells in head and neck cancer. In conformity with the result we examined if this gene could be a competitor gene for chemotherapy. According to literature, the MACC1 gene shows a clear expression in head and neck cancer cells [1]. Here we examined MACC1 expression in CSC and investigated it as a possible biomarker. METHODS: Our experiments were performed in the UT -SCC -74 in primary head and neck cancer cell line. We examined the MACC -1 gene expression by Real Time PCR from both isolated CSC and CS. RESULTS: Expression of MACC -1 gene of cancer stem cells showed an two-fold increase compared with cancer cells. Based on the positive expression of MACC1 in both CS and CSC, this gene may serve as a potential biomarker in head and neck cancer. By comparing the results of this study with the novel features of MACC1, two important hypotheses could be examined. The first hypothesis is that MACC1 is a possible transcripton factor in colon cancer, which influences a high expression of CSC in head and neck and affects the expression of three biomarkers of the CSC control group biomarkers. The second hypothesisis is that the positive expression of MACC1 in patients with a malignant prognosis of tongue cancer, which belongs to head and neck cancer types, operates a faster development of CSC to cancer cells.

Suppression of bromodomain-containing protein 4 by shRNA: A new approach for cancer treatment.

PURPOSE: MYC is a transcription factor coding gene that is believed to control 15% of the genes in the entire human genome. The central role of c-MYC in cancer pathogenesis makes it a major therapeutic target in field of anticancer agent development. METHODS: We targeted the acetyl-lysine binding modules or bromodomains, which are associated with c-MYC transcriptional activation. RESULTS: Sequence specific inhibition of BET bromodomains with small hairpin RNAs (shRNAs) resulted in cessation of cellular proliferation in different cancer cell lines. Unlike previous studies on inhibition of bromodomains with selective small-molecule inhibitors, our study revealed the significant role of BET bromodomains in solid tumours and also highlighted the ease of RNA interference (RNAi) methodology for inhibition of bromodomain translation. CONCLUSION: The degree of influence of BET bromodomain inhibition on proliferation in five cancer cell lines established it as the major target in malignancies characterized by activation of c-MYC.

Investigation of the expression of RIF1 gene on head and neck, pancreatic and brain cancer and cancer stem cells.

PURPOSE: Recent studies have shown that cancer stem cells are resistant to chemotherapy. The aim of this study was to compare RIF1 gene expression in head and neck, pancreatic cancer and glioma cell lines and the cancer stem cells isolated from these cell lines. METHODS: UT-SCC-74 from Turku University and UT-SCC-74B primary tumor metastasis and neck cancer cell lines, YKG-1 glioma cancer cell line from RIKEN, pancreatic cancer cell lines and ASPC-1 cells from ATCC were grown in cell culture. To isolate cancer stem cells, ALDH-1 for UT-SCC-74 and UT-SCC-74B cell line, CD-133 for YKG-1 cell line and CD-24 for ASPC-1 cell line, were used as markers of cancer stem cells. RNA isolation was performed for both cancer lines and cancer stem cells. RNAs were converted to cDNA. RIF1 gene expression was performed by qRT-PCR analysis. RIF1 gene expression was compared with cancer cell lines and cancer stem cells isolated from these cell lines. The possible effect of RIF1 gene was evaluated. RESULTS: In the pancreatic cells, RIF1 gene expression in the stem cell-positive cell line was 256 time that seen in the stem cell-negative cell line. CONCLUSION: Considering the importance of RIF1 in NHEJ and of NHEJ in pancreatic cancer, RIF1 may be one of the genes that plays an important role in the diagnoses and therapeutic treatment of pancreatic cancer. The results of head and neck and brain cancers are inconclusive and further studies are required to elucidate the connection between RIF1 gene and these other types of cancers.

Leptin induces ADAMTS-4, ADAMTS-5, and ADAMTS-9 genes expression by mitogen-activated protein kinases and NF-ĸB signaling pathways in human chondrocytes.

Elucidation of the causes of inflammation has vital importance in the development of new approaches for the treatment of arthritic diseases. The degradation of aggrecan by upregulated disintegrin and metalloproteinase with trombospondin motifs (ADAMTSs) is the key event in the development of both rheumatoid arthritis (RA) and osteoarthritis (OA). Increased levels of leptin in both RA and OA have been demonstrated, thus linking leptin to arthritic diseases, but the mechanism has not been clarified. This study investigated the putative role of signaling pathways (p38, JNK, MEK1, NF-ĸB, and PI3) involved in leptin-induced cartilage destruction. Normal human articular chondrocytes were cultured with recombinant human leptin at 100, 250, 500, and 1000 ng/mL doses for 6, 12, 24, and 48 h, after which ADAMTS-4, -5, and -9 genes expression were determined by real time-polymerase chain reaction (RT-PCR) and Western Blot methods. The signaling pathways involved in leptin-induced ADAMTSs upregulation were also investigated by using inhibitors of signaling pathways. It was demonstrated that ADAMTSs expression level was peaked at 1000 ng/mL doses for 48 hours, and MAPKs (p38, JNK, and MEK) and NF-ĸB signaling pathways involving in leptin triggered ADAMTSs upregulation. Obesity as a risk for RA and OA may contribute to the inflammation of both RA and OA diseases by secreting adipokines like leptin. We hypothesize that leptin is involved in the development of RA and OA accompanied with obesity by increasing ADAMTS-4, -5, and -9 genes expression via MAPKs and NF-ĸB signaling pathways.

The role of Human Dectin-1 Y238X Gene Polymorphism in recurrent vulvovaginal candidiasis infections.

Recurrent vulvovaginal candidiasis (RVVC) is defined as having four or more symptomatic vulvovaginal candidiasis (VVC) attacks within a year. This study aimed to investigate whether Human Dectin-1 Y238X Gene Polymorphism plays a role in RVVC pathogenesis. In order to examine and explore this aim, an experimental study was undergone. The clinical study design was conducted with 50 women diagnosed with RVVC and had four or more symptomatic VVC attacks who were included in the experimental group; while 50 women who did not have previous RVVC history and diagnosis and did not have vaginal discharge and itching in the past year were included in the control group. Blood samples were collected from these patients and transferred to EDTA tubes, to investigate the Dectin-1 Y238X gene polymorphism, and stored at -80°. When Dectin-1 genotypes were compared, there was no significant difference between the two groups (p = 0.452, p = 0.615, p = 0.275). History of familial RVVC was significantly higher in the experimental group (p = 0.001). When the multivariate analysis was used to evaluate factors that could determine RVVC frequency, history of familial RVVC was found to increase the frequency of RVVC attacks by 3.3 units. This study is the first-of-its-kind to investigate the correlation between Dectin-1 Y238X polymorphism, which has not been previously studied in the Turkish population, and RVVC. The result of this study suggests that there is no correlation between this polymorphism and RVVC.

The effects of hypericin on ADAMTS and p53 gene expression in MCF-7 breast cancer cells.

PURPOSE: The purpose of this study was to determine the effects of hypericin on MCF-7 (Michigan Cancer Foundation- 7) breast cancer cells, as it is known to exert an antitumor effect on the expression and regulation of ADAMTS1, 3, 10 and the p53 gene in breast cancer cells. METHODS: MFC-7 cells were cultured and subjected separately to various doses (1, 5 and 7.5 µg /mL) hypericin. After 24 hrs, RNA was isolated and transcribed into cDNA. Expression analysis was performed by real time (RT)-PCR and cell survival was determined by the XTT assay. RESULTS: While the expression of ADAMTS1 in MFC-7 cells decreased to 0.04-fold after exposure to 1 µg /mL hypericin, the expression increased by 5.6- and 36-fold with 5 and 7.5 µg/mL, respectively. Furthermore, ADAMTS3 expression in MCF7 cells increased 3.9-fold with the use of 5 µg /mL of hypericin. These concentrations of hypericin did not lead to significant changes in the expression of ADAMTS10 and the p53 gene. Viability of cancer cells as evaluated by the XTT assay showed that hypericin concentration of 7.5 µg /mL led to increased apoptosis of cancer cells. CONCLUSION: The increase in ADAMTS1 expression may prevent metastasis or facilitate the development of an adjuvant factor with tumor-suppressive effects. Hypericin may therefore exert its antitumor and apoptotic effects in MFC-7 cells via ADAMTS1 and ADAMTS3.

Cancer Stem Cells in Oropharyngeal Cancer.

Oropharyngeal cancer (OPC), which is a common type of head and neck squamous cell carcinoma (HNSCC), is associated with tobacco and alcohol use, and human papillomavirus (HPV) infection. Underlying mechanisms and as a result prognosis of the HPV-positive and HPV-negative OPC patients are different. Like stem cells, the ability of self-renewal and differentiate, cancer stem cells (CSCs) have roles in tumor invasion, metastasis, drug resistance, and recurrence after therapy. Research revealed their roles to some extent in all of these processes but there are still many unresolved points to connect to CSC-targeted therapy. In this review, we will focus on what we currently know about CSCs of OPC and limitations of our current knowledge. We will present perspectives that will broaden our understanding and recent literature which may connect to therapy.

Osteopontin silencing attenuates bleomycin-induced murine pulmonary fibrosis by regulating epithelial-mesenchymal transition.

Idiopathic pulmonary fibrosis (IPF) is the most common and most deadly form of interstitial lung disease. Osteopontin (OPN), a matricellular protein with proinflammatory and profibrotic properties, plays a major role in several fibrotic diseases, including IPF; OPN is highly upregulated in patients' lung samples. In this study, we knocked down OPN in a bleomycin (BLM)-induced pulmonary fibrosis (PF) mouse model using small interfering RNA (siRNA) to determine whether the use of OPN siRNA is an effective therapeutic strategy for IPF. We found that fibrosing areas were significantly smaller in specimens from OPN siRNA-treated mice. The number of alveolar macrophages, neutrophils, and lymphocytes in bronchoalveolar lavage fluid was also reduced in OPN siRNA-treated mice. Regarding the expression of epithelial-mesenchymal transition (EMT)-related proteins, the administration of OPN-siRNA to BLM-treated mice upregulated E-cadherin expression and downregulated vimentin expression. Moreover, in vitro, we incubated the human alveolar adenocarcinoma cell line A549 with transforming growth factor (TGF)-ß1 and subsequently transfected the cells with OPN siRNA. We found a significant upregulation of Col1A1, fibronectin, and vimentin after TGF-ß1 stimulation in A549 cells. In contrast, a downregulation of Col1A1, fibronectin, and vimentin mRNA levels was observed in TGF-ß1-stimulated OPN knockdown A549 cells. Therefore, the downregulation of OPN effectively reduced pulmonary fibrotic and EMT changes both in vitro and in vivo. Altogether, our results indicate that OPN siRNA exerts a protective effect on BLM-induced PF in mice. Our results provide a basis for the development of novel targeted therapeutic strategies for IPF.

Tumor-specific mutation and downregulation of ING5 detected in oral squamous cell carcinoma.

Our previous study showed high frequency of allelic loss at chromosome 2q37 region in oral cancer. This location contains several candidate tumor suppressor genes such as PPP1R7, ILKAP, DTYMK and ING5. We previously showed 3 members of inhibitor of growth (ING) family, ING1, ING3 and ING4 as tumor suppressor gene in head and neck cancer. As ING5 shows high homology with other members of ING genes including highly conserved carboxy-terminal plant homeodomain and nuclear localization signal, we first picked up ING5 and examined it as a possible tumor suppressor in oral cancer. For this aim, mutation and mRNA expression status of ING5 in paired normal and oral squamous cell carcinoma samples were examined by reverse transcription polymerase chain reaction (RT-PCR) and sequencing. Three missense mutations located within leucine zipper like (LZL) finger and novel conserved region (NCR) domains in ING5 protein were detected, probably abrogating its normal function. We also found 5 different alternative splicing variants of ING5. Then, we examined mRNA level of ING5 by quantitative real time reverse transcription polymerase chain reaction (qRT-PCR) analysis, which demonstrated decreased expression of ING5 mRNA in 61% of the primary tumors as compared to the matched normal samples. In conclusion, tumor-specific mutation and downregulation of ING5 mRNA suggested it as a tumor suppressor gene in oral squamous cell carcinoma.

Frequent allelic loss of Dkk-1 locus (10q11.2) is related with low distant metastasis and better prognosis in head and neck squamous cell carcinomas.

Head and neck squamous cell carcinoma (HNSCC) is a frequently occurring cancer worldwide. Dickkopf (Dkk)-1 gene is suggested to function as tumor suppressor gene (TSG) in several kinds of malignancies. In this study, we performed loss of heterozygosity (LOH) analysis of Dkk-1 and examined the correlation between LOH status and clinicopathological parameters for the first time. A pretty high LOH ratio (50%) was detected. Interestingly, in the cases with Dkk-1 retention group showed less distant metastasis and a tendency of longer disease free survival. These results indicate that Dkk-1 can play a role in HNSCC carcinogenesis and it may also be related to distant metastasis.

Expression and mutation analysis of her2 in head and neck squamous cell carcinoma.

We analyzed mutation and expression status of human epidermal growth factor receptor 2 (Her2) in head and neck squamous cell carcinoma (HNSCC) using single strand conformation polymorphism (SSCP) mutation analysis and immunohistochemistry (IHC). Mutations were absent in all 85 cases. Out of 57 cases available for IHC, Her2 protein expression was negative (0) in 40 tumors (70%). Seventeen tumors (29.8%) expressed Her2, among these 13 tumors (22.8%) showed a weak (+1) expression and 4 (7%) showed a moderate expression (+2), none showed a strong (+3) expression. There was not a significant association between expression and any of the patients' clinical variables or prognosis. Our results suggest that Her2 may not be useful as a molecular target in HNSCC.

Allelic loss of the ING gene family loci is a frequent event in ameloblastoma.

Ameloblastoma is the most frequently encountered odontogenic tumor, characterized by a locally invasive behavior, frequent recurrences, and, although rare, metastatic capacity. Loss or inactivation of tumor suppressor genes (TSGs) allows cells to acquire neoplastic growth. The ING family proteins are tumor suppressors that physically and functionally interact with p53 to perform important roles in apoptosis, DNA repair, cell cycle regulation, and senescence. TP53 genetic alterations were reported to infrequently occur in ameloblastoma. Considering that other TSGs related to TP53 could be altered in this tumor, we focused our study on the ING family genes. We analyzed the loss of heterozygosity (LOH) status of the ING family (ING1-ING5) chromosomal loci in a group of ameloblastomas by microsatellite analysis, and correlated the ING LOH status with clinicopathological characteristics. By using specific microsatellite markers, high frequency of LOH was found at the loci of each ING gene family member (33.3-72.2%). A significant relationship was shown between LOH of D2S 140 (ING5 locus) and solid tumor type (p = 0.02). LOH of ING3MS (ING3 locus) was also high in solid type tumors, showing a near significant association. In addition, a notable tendency toward higher LOH for half of the markers was observed in recurrent cases. LOH of ING family genes appears as a common genetic alteration in solid ameloblastoma. The current study provides interesting novel information regarding the potential prognostic significance of the allelic loss of the ING gene family loci in ameloblastoma tumorigenesis.

Identification and chemoresistance of cancer stem cells in HPV-negative oropharyngeal cancer.

The underlying mechanisms of resistance to chemoradiotherapy of human papilloma virus (HPV)-negative patients with oropharyngeal cancer (OPC) remain unclear. The present study aimed to characterize cancer stem cells (CSC) of the HPV-negative OPC cell line in terms of chemotherapy resistance. CSCs were isolated through magnetic activated cell sorting using the CSC specific marker aldehyde dehydrogenase 1 antibody, and characterized by sphere formation capacity, immunofluorescence staining, and CSC marker expression. CSC response to cisplatin treatment was evaluated via XTT-assays. Spheres of CSCs of the HPV-negative UTSCC-60A cell line were highly dark holospheres. RNA expression levels of CSC markers OCT4, SOX2, Kruppel-like factor 4 and BMI1 were significantly higher in CSC. CSCs were significantly resistant to cisplatin treatment at various dosages compared with nonCSC. The present study suggested that the proportion of CSCs is very low in the tumor bulk, CSCs are resistant to cisplatin in HPV-negative OPC, which requires further investigation to define their mechanism.

MicroRNA 200b promotes mesenchymal-to-epithelial transition in anaplastic thyroid carcinoma.

Anaplastic thyroid cancer (ATC) remains a cancer with one of the worst prognoses, despite novel targeted therapies. The median survival rate has not improved for decades. Epithelial-to-mesenchymal transition (EMT) is a crucial step in physiological processes and in cancer progression, but the underlying mechanisms are not yet fully understood. The current study examined the role of microRNA (miR)-200b in mesenchymal-to-epithelial transition in ATC. Total RNA and miR isolation were performed from ATC cell lines transfected with a miR-200b mimic. After miR-200b mimic transfection, expression levels of E-cadherin, vimentin and zinc finger E-box binding homeobox 1 (ZEB1) were confirmed by reverse transcription-quantitative PCR and western blotting. Additionally, cell migration was evaluated using miR-200b mimic and scrambled negative control-transfected cells. A total of 14 human ATC and 15 non-cancerous human thyroid tissues were immunohistochemically stained and scored as controls for E-cadherin, vimentin and ZEB1. In ATC tissues and cell lines, the mesenchymal marker ZEB1 was significantly upregulated and the epithelial marker E-cadherin was significantly downregulated. Additionally, the mesenchymal marker vimentin was significantly upregulated in ATC tissues and in one ATC cell line. MiR-200b mimic transfection significantly increased vimentin and ZEB1 expression, but E-cadherin expression remained below the measurement sensitivity. Furthermore, miR-200b overexpression decreased cell migration. The current study suggested that miR-200b may regulate the expression levels of mesenchymal markers such as vimentin and ZEB1 in ATC and may promote mesenchymal-to-epithelial transition.

T-lymphocyte maturation-associated protein gene as a candidate metastasis suppressor for head and neck squamous cell carcinomas.

Previous gene expression profiles revealed the T-lymphocyte maturation-associated protein (MAL) gene as being frequently downregulated in head and neck cancer. To define the relationship between the MAL gene and the metastatic process, we evaluated the expression status of the gene in matched primary and metastatic tumors of head and neck cancer by semiquantitative reverse transcription-polymerase chain reaction. Furthermore, we aimed to identify potential genetic and epigenetic mechanisms associated with downregulation of MAL, including loss of heterozygosity (LOH), mutation, and hypermethylation. Thirty-five cell lines of University of Turko squamous cell carcinoma (UT-SCC) series derived from head and neck cancer, including nine pairs from matched primary and metastatic tumors, and 30 pairs of matched primary and metastatic tumor samples were analyzed. Twenty out of 35 (57%) cell lines showed downregulation of MAL expression, whereas no expression was found in 10 cell lines (29%). Considering matched primary and metastatic tumor-derived cell-line pairs, four pairs showed decreased expression only in metastasis-derived cells compared with their primary counterparts. Expression analysis of 21 tissue samples demonstrated decreased or no expression of MAL mRNA in 43% of metastatic tumors compared with matched primary tumors. Relating to mechanisms of downregulation, LOH was observed in 30% of primary tumors and 38% of their metastatic counterparts by a MAL-specific microsatellite marker. Furthermore, we found restoration of MAL mRNA after treatment with demethylating agent (5-aza-2'-deoxycytidine) in 9 (45%) out of 20 cell lines. No mutation was found in UT-SCC cell lines. In conclusion, our findings indicate selective downregulation of MAL expression in metastatic cells, suggesting the MAL gene as a new metastasis-suppressor candidate for head and neck cancer. LOH and hypermethylation appeared to be important mechanisms for inactivation of MAL function.

Loss of heterozygosity at the 9p21-24 region and identification of BRM as a candidate tumor suppressor gene in head and neck squamous cell carcinoma.

We have analyzed allelic loss of the short arm of chromosome 9 in 39 head and neck cancers using 13 polymorphic markers and found two deletions of hot spots at 9p21 and 9p24. Loss of heterozygosity was detected at least at one locus in 28 of 39 cases (71.8%). P16, a well-known tumor suppressor gene, is considered to be a target for deletion of the 9p21 region. However, novel frequent chromosomal deletion and a candidate tumor suppressor gene, BRM at the 9p24 region, were detected. Moreover, comparison of clinicopathological variables demonstrated that loss of heterozygosity at the BRM locus was associated with a worse prognosis.

Fine deletion analysis of 1p36 chromosomal region in oral squamous cell carcinomas.

BACKGROUND: Squamous cell carcinoma is the most common cancer type of the oral cavity and approximately 50% of the patients succumb to the disease. Unfortunately, few are known about the molecular mechanisms involving in the formation of oral squamous cell carcinoma (OSCC). Recently, it has been reported that 1p36 chromosomal region is deleted in various cancer types and is suspected to harbor various tumor suppressor genes (TSGs). However, limited studies exist on genetics alteration on 1p36 in OSCC and the responsible TSG remained unidentified. METHODS: To investigate area susceptible to harbor TSG(s) involved in OSCC on 1p36 region, paired normal and tumor tissues of 27 patients with diagnosis of OSCC have been analyzed for loss of heterozygosity (LOH) using nine microsatellite markers based on recent gene mapping. RESULTS: LOH was found at least in one locus in 85% of the cases (23 of 27). Interestingly, microsatellite instability was also found in 7% (two of 27) of the cases analyzed. The higher LOH frequencies were found with the markers D1S243 (25%), D1S468 (22%), D1S450 (25%), D1S228 (38%), D1S199 (28%), and D1S1676 (23%). CONCLUSIONS: Three preferentially deleted regions have been identified in OSCC: region 1 (D1S468-D1S243), region 2 (D1S450-D1S228), and region 3 (D1S199-D1S1676). Multiple candidate TSGs, such as RIZ1, p73, UBE4B, Rap1GAP, EPHB2, and RUNX3, are located in these three areas. The data obtained in this study can be used for further functional analysis of these genes involved in OSCC carcinogenesis.