Molecular pathways of oral cancer that predict prognosis and survival: A systematic review.

Several genes and pathways associated with oral squamous cell carcinoma (OSCC) are significant in terms of early detection and prognosis. The objective of this literature review is to evaluate the current research on molecular pathways and genes involved in oral cancer. Articles on the genes involved in oral cancer pathways were evaluated to identify potential biomarkers that can predict survival. In total, 36 articles were retrieved from internet databases, including EBSCO Host, Google Scholar, PubMed, and Science Direct, using the keywords "biomarker of oral cancer," "pathways of oral cancer," "genes involved in oral cancer," and "oral cancer pathways." A total of 36 studies related to OSCC were chosen. Most of the studies used cell lines, while others used archival tissues, few studies followed up the cases. Three major interlinked pathways found were the nuclear factor kappa B (NF-kB), PI3K-AKT, and Wnt pathways. The commonly mutated genes were cyclin D1 (CCND1), Rb, p53, FLJ10540, and TC21. The NF-kB, PI3K-AKT, and Wnt pathways are most frequently involved in the molecular pathogenesis of oral cancer. However, the CCND1, Rb, p53, FLJ10540, and TC21 genes were found to be more accurate in determining patients' overall survival. Polymerase chain reaction, immunohistochemistry, and immunoblotting were the commonly used detection methods.

Expression of hTERT in Oral Submucous Fibrosis and Oral Squamous Cell Carcinoma - an Immunohistochemical Analysis.

Human telomerase reverse transcriptase enzyme, the catalytic subunit of telomerase are seen to be frequently reactivated in cancers including Oral squamous cell carcinoma (OSCC). Increased hTERT expression have been seen in potentially malignant conditions including Oral submucous fibrosis (OSMF). The aim of the study was to evaluate the expression levels in OSMF, OSCC in the background of OSMF and OSCC using immunohistochemistry and also to correlate hTERT expression with clinicopathologic parameters. A total of 50 histopathologically diagnosed cases of 20 OSMF, 20 OSCC wherein 5 were OSCC in the background of OSMF and 10 Normal oral mucosae were retrieved from the departmental archives and subjected to immunohistochemical analysis of hTERT. The expression of hTERT increased from normal, OSMF, to OSCC with statistically significant differences in mean labelling score (LS). We also found a shift in cellular localization of stain where, normal mucosal tissues showed a nuclear stain unlike OSMF, where combined nuclear and cytoplasmic staining as noted. The tumor cells in OSCC showed predominant cytoplasmic staining. There was no correlation between hTERT expression and clinicopathological parameters of OSMF. However, a significant increase of hTERT expression was seen with increasing histological grading of OSCC. These results suggest the role of hTERT in the early event of malignant transformation of OSMF. Telomerase could be used as a potent diagnostic marker to identify high-risk group of OSMF.

Interleukin-1beta and Caspase-3 expression serve as independent prognostic markers for metastasis and survival in oral squamous cell carcinoma.

BACKGROUND: The Indian subcontinent has the highest incidence and prevalence of oral squamous cell carcinoma (OSCC). Inflammation and apoptosis are two emerging hall marks of cancer that might play a significant role in tumorigenesis and metastasis. Concurrent expression of proinflammatory cytokine (IL-1ß) and executioner caspase (Caspase-3) in same OSCC tissue samples has not been reported in an Indian population. OBJECTIVES: The present study aimed to evaluate the immunohistochemical expression of IL-1ß and Caspase-3 in same OSCC tissue samples with clinicopathological correlation and survival analysis in Indian population. METHODS: A retrospective study was conducted utilizing 40 formalin fixed paraffin embedded histologically diagnosed cases of OSCC comprising of 20 metastatic OSCC and 20 non-metastatic OSCC. RESULTS: Increased expression of IL-1ß and Caspase-3 were observed in metastatic OSCC. Correlation of expression of IL-1ß and Caspase-3 with clinicopathological parameters revealed a significant association between these markers and staging, nodal status and site of the lesion. CONCLUSION: Over expression of IL-1ß and Caspase-3 was associated with advanced stage and poor survival of the patient. IL-1ß overexpression showed significantly lower disease-free survival and disease specific survival as well. Overexpression of IL-1ß and Caspase-3 in incisional OSCC biopsies could be considered for predicting metastasis and survival outcome.

Stem Cell Markers SOX-2 and OCT-4 Enable to Resolve the Diagnostic Dilemma between Ameloblastic Carcinoma and Aggressive Solid Multicystic Ameloblastoma.

BACKGROUND: Ameloblastic carcinoma (ACA) is a malignant neoplasm with overlapping histopathological features of benign aggressive solid multicystic ameloblastoma (SMA). This often leads to misdiagnosis with direct implication on the management protocol. The need of the hour is to adopt reliable tissue biomarkers to differentiate these lesions accurately that will help to implement an appropriate treatment modality. Few studies to differentiate ACA and SMA in literature with a limitation of a single marker and lack of availability of cases have prompted us to undertake this study. Thereby, this study is aimed at resolving the diagnostic dilemma in differentiating ACA and aggressive SMA using SOX-2, OCT-4 and CD44. MATERIALS AND METHODS: Tissue samples involved 40 archival cases of histopathologically confirmed cases of ACA (n = 20) and SMA (n = 20). The sections were subjected to immunohistochemical staining using antibodies to SOX-2, OCT-4 and CD44. Nuclear staining for SOX-2 and OCT-4 and membranous reactivity for CD44 was considered positive. RESULTS: The expression of SOX-2 and OCT-4 in ACA was statistically significant when compared to SMA (P < 0.001). CD44 showed an insignificant statistical value of <0.077 in differentiating ACA and SMA. SOX-2 and OCT-4 expression in ACA showed a significant correlation coefficient of 0.616 at P < 0.004. CONCLUSIONS: SOX-2 and OCT-4 could serve as independent novel markers in resolving the diagnostic dilemma between ACA and aggressive SMA.

Efficacy of centrifuged liquid-based cytology over conventional cytology: A comparative study.

BACKGROUND: Exfoliative cytology is the microscopic examination of a shed or desquamated cells from the epithelial surface. Centrifuged liquid-based cytology (CLBC) is a modified technique that is used in the current study. AIMS: To compare the efficacy of CLBC with conventional cytology in apparently normal mucosa and histologically proven cases of oral squamous cell carcinoma after staining with Papanicolaou stain. MATERIALS AND METHODS: The study sample was collected from fifty individuals with no habits and apparently normal oral mucosa (Group 1) and forty cases of histologically proven cases of oral squamous cell carcinoma (Group 2). One smear was taken and spread on the slide by a conventional technique. The second sample was flushed out in a suspending solution, centrifuged, and the cell pellet obtained was used to make the smear. The stained smears were compared for nine parameters such as adequate cellularity, clear background, uniform distribution, cellular overlapping, cellular elongation, mucus, inflammatory blood, and microbial colonies. Chi-square test was used for statistical analysis and P ≤ 0.05 was considered statistically significant. RESULTS: There was a statistically significant result with parameters such as adequate cellularity, clear background, uniform distribution, cellular overlapping, and cellular elongation in CLBC technique, in comparison with the conventional technique. The presence of mucus, microbial colonies, and inflammatory cells were also less in CLBC technique in comparison with the conventional technique. CONCLUSION: CLBC has better efficacy over conventional method in all the parameters analyzed.

Basaloid Squamous Cell Carcinoma of Tongue: A Report with Emphasis on Immunohistochemistry.

Basaloid Squamous Cell Carcinoma (BSCC) is a rare entity with its histopathological distinction from conventional squamous cell carcinoma. It is frequently considered a high-grade carcinoma with poor prognosis because of higher rate of distant metastases. Here by, we are reporting a case of 39-year-old male with an ulcer on the left lateral border of the tongue since a month. Histopathological examination of incisional biopsy revealed basaloid tumour cell islands accompanied by component of well differentiated squamous cell carcinoma. To reconfirm this incidental finding immunohistochemistry was carried out for Proliferative Cell Nuclear Antigen (PCNA) and pancytokeratin (AE1/AE3) which was positive to conclude diagnosis of BSCC. Further p16 staining was done to rule out Human Papilloma Virus (HPV) infection.

Possible Role of Bcl-2 Expression in Metastatic and Non Metastatic Oral Squamous Cell Carcinoma.

INTRODUCTION: Oral carcinoma is a global health problem. India accounts for one-third of world burden with high prevalence rate of 2.5 million and mortality rate of 5.5 lacs per year. Oral carcinogenesis is a multistage process that frequently involves invasion and metastasis that needs early detection and treatment to improve the overall quality of life. The ability of Oral Squamous Cell Carcinoma (OSCC) to metastasize to lymph nodes does not always show a relationship with clinical staging. A spectrum of molecular mechanisms is involved in carcinogenesis, where defect in the regulation of apoptosis is assumed to contribute to the pathogenesis and progression of cancer. Apoptosis regulatory genes include the antiapoptotic protein such as B-cell lymphoma-2 (Bcl-2) gene that might be used as a molecular marker to evaluate the biological behaviour of oral cancer. AIM: To evaluate and correlate the Bcl-2 expression in OSCC patients with lymphnode metastasis and without metastasis. MATERIALS AND METHODS: The study comprised of 30 samples, 15 cases of metastatic and 15 non-metastatic primary OSCC. All the cases were stained for routine Hematoxylin and Eosin (H&E), and Bcl-2 antibody by immunohistochemistry. The H&E stained sections were evaluated for Lymphocytic Infiltrate (LI) and Pattern Of Invasion (POI). Bcl-2 stained sections were evaluated for staining intensity and distribution. The differences between the groups were statistically analysed using chi-square test. RESULTS: The histopathological parameters, LI and POI did not show any statistical difference between the study groups. Expression of Bcl-2 in OSCC was 33.3% among the study groups, where metastatic group showed a positive expression of 13.3% and 20% in non-metastatic OSCC that did not show statistically significance among the study groups. CONCLUSION: There was no significant difference in the expression of Bcl-2 between the study groups. Apoptosis is regulated by interaction among the Bcl-2 gene family. Hence, evaluation of Bcl-2 along with other apoptotic regulating proteins could define the role in pathogenesis and prognosis of metastatic and non-metastatic OSCC.

Biomarkers in Tumorigenesis Using Cancer Cell Lines: A Systematic Review

Cancer is a leading cause of death worldwide. Despite many research advancements in the field, the genetic changes regulating the transformation of normal oral cells into malignant cells have not been fully elucidated. Several studies have evaluated carcinogenesis at the molecular level. Cancer cell lines are commonly used in biomedical research because they provide an unlimited source of cells and represent various stages of initiation and progression of carcinogenesis in vitro. Aims: The objective of the study was to review original research articles using cancer cell lines as a tool to understand carcinogenesis and to identify the genes involved in tumor development. Additionally, we also examined the application of the genes as predictive biomarkers. Methods and Materials: Several databases, including PubMed, Google Scholar, Ebsco, and Science Direct, were searched from 1985 to December 2016 using various combinations of the following key words: "mouth neoplasm", "cell lines", and "tumorigenesis". Original experimental studies published in English were included. We excluded letters to the editor, historic reviews, and unpublished data from the analysis. Results: There were 17 studies (in vitro) included in the analysis. There were 14 genes and 4 miRNAs involved in malignant transformation of oral keratinocytes into cancer cells. The most commonly studied genes were p53, cyclin D1, and hTERT. Conclusion: Additional reviews and studies are needed to identify a panel of genes specific to various potentially malignant disorders and to aid in the early detection of oral squamous cell carcinoma (OSCC) because tumorigenesis involves the mutation of multiple genes. Furthermore, improving advanced cost-effective diagnostic methods may benefit the public health sector.

Naturally Available Extracts Inhibiting Cancer Progression: A Systematic Review.

AIM: This systematic review is aimed at evaluating the literature on the efficacy of naturally available extracts that inhibit cancer. METHODS: A literature search was performed to strengthening the reporting of observational studies in epidemiology analysis. Approximately 3000 research articles were initially selected. Of these articles, 200 were included, and 2800 were excluded. On further scrutiny, 150 of the 200 studies were reviews, seminars, and presentations, and 50 were original study articles. Among these articles, 20 studies were selected for the systematic review. RESULTS: The predominant molecular pathways followed by natural extracts were nuclear factor kappa B ligand, suppression of the protein kinase B-Akt/P13K pathway (an intracellular signaling pathway important in regulating cell cycle), vascular endothelial growth factor downregulation, and tumor protein-P53 tumor suppressor upregulation. CONCLUSIONS: It is evident that natural extracts have the ability to inhibit cancer progression. Continued research in this field could facilitate the use of natural extracts with currently available anticancer agents.

Apoptosis in oral epithelial dysplastic lesions and oral squamous cell carcinoma: A prognostic marker.

BACKGROUND: Apoptotic index (AI) using light microscopy as an indirect measure to assess the significance of apoptosis as a proliferative marker in dysplastic lesions and malignant epithelial lesions of the oral cavity. AIMS: (1) To quantify the apoptotic bodies/cells in oral epithelial dysplastic (OED) lesions and oral squamous cell carcinoma (OSCC). (2) To measure AI in OED and OSCC. (3) To compare AI in OED and OSCC. SETTINGS AND DESIGN: The proposed laboratory-based retrospective study involved the use of hematoxylin and eosin (H and E)-stained slides of previously diagnosed OED lesions and OSCC from institutional archives. MATERIALS AND METHODS: This study constituted 50 cases, each of H and E-stained slides of previously diagnosed cases of OED and OSCC. AI was calculated as the number of apoptotic bodies/cells expressed as a percentage of the total number of nonapoptotic tumor/dysplastic cells counted in each case. STATISTICAL ANALYSIS USED: Nonparametric tests such as Kruskal-Wallis test and Mann-Whitney test were used. RESULTS: There was a statistically significant increase in AI from OED to OSCC (P = 0.000). CONCLUSIONS: Further studies need to be undertaken to detect and understand the apoptotic mechanisms in the progression from OED to OSCC.

Improvization of conventional cytology by centrifuged liquid-based cytology in oral exfoliative cytology specimen.

BACKGROUND: Exfoliative cytology is the microscopic examination of shed or desquamated cells from the epithelial surface. Centrifuged liquid-based cytology (CLBC) is a modified technique that was used in the current study. AIMS: To compare the efficacy of CLBC with conventional cytology in apparently normal mucosa after staining with Papanicolaou (PAP) stain. MATERIALS AND METHODS: Fifty cases of apparently normal mucosa from healthy subjects were selected for the study. The first sample was taken and spread on the slide by the conventional technique. The second sample was flushed out in a suspending solution, centrifuged, and the cell pellet obtained was used to make the smear. The stained smears were compared for seven parameters such as adequate cellularity, clear background, uniform distribution, cellular overlapping, cellular elongation, mucus, and inflammatory cells. Chi-square test was used for statistical analysis and P ≤ 0.05 was considered to be statistically significant. RESULTS: There was a statistically significant difference between CLBC and conventional cytology with parameters such as adequate cellularity (P = 0.001), clear background (P = 0.001), uniform distribution (0.005), cellular overlapping, and cellular elongation (P = 0). The presence of mucus and inflammatory cells was minimal as the samples were collected from healthy subjects. CONCLUSION: CLBC has better efficacy over the conventional method in all the parameters analyzed.