microRNA Profile in Early-stage Cervical Cancer
microRNA Profile in Early-stage Cervical Cancer
Persistent infections with high-risk subtypes of the human papillomavirus (HPV) are
 recognized as the etiological factor for developing cervical cancer. The aim od this study
 was to identify a miRNA profile in patients with early-stage cervical cancer with positive
 lymph node metastasis treated. Formalin-fixed paraffin-embedded (FFPE) tissue samples of
 patients with a diagnosis of early-stage cervical cancer treated by radical hysterectomy with
 lymphadenectomy were collected.
Cervical carcinoma (CC) is one of the most common cancers in women from countries with
 emerging economies; in Mexico, CC has the second highest incidence and mortality rate.
 Several studies have demonstrated that the most important prognostic factor is lymph node
 metastasis in early-stage CC patients prior to radical hysterectomy (RH) with bilateral
 pelvic lymphadenectomy (BPL), in which positive lymph node metastasis decreasing overall
 survival (OS) from 80% to 53% at 5 years.

 MicroRNAs (miRNAs) are single-strand RNAs comprising approximately 21-23 nucleotides. miRNAs
 regulate gene expression through the inhibition of posttranscriptional events and, in some
 cases, induce the degradation of their target messenger RNA. In cancer, miRNAs can function
 as both oncogenes and/or as tumor suppressor genes depending on the function of their target
 genes.

 Formalin-fixed paraffin-embedded (FFPE) tissue blocks from CC patients diagnosed between
 January 2006 and December 2013 at the Department of Oncologic Gynecology of the National
 Cancer Institute (Mexico City) were analyzed with the intention of selecting those with a
 confirmed histopathological diagnosis of stages IB1 or IIA1 CC treated with RH and BPL. Total
 RNA was extracted from 5 (10-µm) sections for selected tissues.For the clinical correlation
 analysis, the samples were divided into 2 groups: 1 with positive occult lymph node
 metastasis pathology and 1 without lymph node metastasis pathology. For both groups, patients
 were matched for age, tumor size and presence of lymphovascular permeation.

 The identification of global miRNA profiles was performed using GeneChip miRNA 3.0 Array
 (Affymetrix, Cat. 902018) following the manufacturer's instructions. the microarray was
 hybridized and washed using the Affymetrix Fluidics Station 450 and scanned with the
 Affymetrix GeneChip Scanner 3000. After processing the images, the raw data were processed.
 To obtain the miRNA profile, the processed samples were divided into 2 groups, samples with
 lymph node metastasis and samples without lymph node metastasis. Differentially expressed
 miRNAs were identified using a cutoff value of p <0.01 and a fold change (FC) of 1.5. miRNAs
 that met these criteria were classified as over-expressed or under-expressed.
Inclusion Criteria:

 -  Cervical cancer histopathological diagnosis

 -  Clinical stage IB1 or IIA1 CC

 -  Treated with radical hysterectomy (RH) with bilateral pelvic lymphadenectomy (BPL)

 Exclusion Criteria:

 -  Double primary tumors

 -  Treatment regimens other than standard treatment

 -  Poor quality formalin-fixed paraffin-embedded tissue blocks