Expression profile of tumor suppressor gene RASSF1 in lacrimal gland carcinoma

Abstract

ABSTRACT. We examined the expression pattern of the tumor suppressor gene RAS association domain family gene 1 (RASSF1) in lacrimal gland carcinoma and analyzed its relationship with the oncogenesis and progression of tumors. Sixty-two patients (30 males, 32 females, average age = 47 ± 3.5 years) admitted with lacrimal gland carcinoma to the Department of Ophthalmology of our hospital between January 2012 and January 2014 were enrolled in this study. Based on tumor malignancy, patients were classified into a malignant group (N = 25) and benign group (N = 37). Healthy lacrimal gland resections from trauma surgery (N = 35) were recruited as a healthy control group. Expression profiles of RASSF1 in all groups were quantified using reverse transcription-polymerase chain reaction and western blotting. Recurrence of lacrimal gland carcinoma was surveyed through postoperative follow-up. Expression levels of RASSF1 in samples from the malignant and benign groups were significantly lower than those in the healthy group (P < 0.05). Furthermore, the malignant group showed lower RASSF1 expression than the benign group (P < 0.05). Postoperative follow-up identified 22 cases of recurrence in the malignant group, with a recurrence rate of 88%, while 15 cases in the benign group had a C.H. Zeng et al. 6994©FUNPEC-RP www.funpecrp.com.br Genetics and Molecular Research 14 (2): 6993-6998 (2015) recurrence rate of 40.5%. A direct relationship exists between RASSF1 expression levels and the malignancy grade of lacrimal gland carcinoma. Patients with lower RASSF1 expression showed a higher recurrence probability, indicating unfavorable prognosis. Therefore, measuring RASSF1 expression can be used as a diagnostic method for lacrimal gland carcinoma.

Expression profiles of selected genes in tumors and matched surgical margins in oral cavity cancer: Do we have to pay attention to the molecular analysis of the surgical margins?

“…21 In the case of the RASSF1 gene, we found no significant differences in our study. A downregulated expression of RASSF1A transcripts and protein in tumor tissues in esophageal and nasopharyngeal carcinomas were observed by Lo et al; moreover, a reduced expression correlated with the histological grade of the tumor.…”

“…In the literature, the expression profiles of many genes have been reported in different types of human cancer, [18][19][20][21] including HNSCC. 12,[22][23][24][25][26][27] The majority of the research has compared tumor tissue from patients with normal tissue from healthy individuals or normal human cells obtained commercially.…”

“…12,[22][23][24][25][26][27] The majority of the research has compared tumor tissue from patients with normal tissue from healthy individuals or normal human cells obtained commercially. 12,18,[20][21][22]28,29 Simultaneous analysis of gene expression levels in the tumor and surgical margins has rarely been performed. 23,26,30 Cancer development is the result of the accumulation of genetic and epigenetic alterations.…”

“…33 The mRNA expression of RASSF1A was also downregulated in primary tumors in a group of patients with cutaneous melanoma and lacrimal gland carcinoma compared to healthy groups, and was also downregulated in lung and breast cancer cell lines. 18,21,43 Furthermore, aberrant methylation of RASSF1A has been observed in several cancer types 43 and a few reports have been focused on the methylation of this gene in HNSCC. 44,45 It is well known that hypermethylation is one of the important epigenetic mechanisms responsible for inactivation of the gene, in addition to genetic alterations of gains and losses.…”

Dioscin induces demethylation of DAPK-1 and RASSF-1alpha genes via the antioxidant capacity, resulting in apoptosis of bladder cancer T24 cells

“…RASSF1α promoter methylation has been used as a biomarker for detecting field cancerization in non-invasive breast cancer and as a prognostic factor in invasive breast cancer (Spitzwieser et al, 2015[10]; Shakeri et al, 2016[8]). Previous studies have documented lower expression of RASSF1α in non-small cell lung cancer, esophageal squamous cell carcinoma and lacrimal gland carcinoma (Zeng et al, 2015[17]). Patients with lower RASSF1α expression showed a higher recurrence probability and unfavorable prognosis (Zeng et al, 2015[17]).…”