No abstract

Stress that impairs endoplasmic reticulum (ER) function leads to an accumulation of unfolded or misfolded proteins in the ER (ER stress). Autophagy is a lysosomal pathway involved in the turnover of cellular macromolecules and organelles, which emerging data indicate that ER stress is also a potent inducer of autophagy. ER stress and autophagy are involved in human cancer. We examined the expression of ER stress-related proteins [GRP78 and C/EBP homologous protein (CHOP)] and autophagic proteins (Beclin-1 and LC3) in non-small cell lung carcinomas (NSCLCs), bronchioloalveolar carcinomas (BACs) and atypical adenomatous hyperplasias (AAHs) to understand their role in the NSCLC pathogenesis. The expression of GRP78 and CHOP, Beclin-1 and LC3 were analyzed using immunohistochemistry on tissue sections from 133 NSCLC (69 squamous cell carcinomas, 56 adenocarcinomas (AC) and eight other NSCLCs), 21 BAC and 9 AAH. Expression of GRP78 and Beclin-1 was correlated with low tumor stage (p < 0.001 and p 5 0.019, respectively) and longer survival (p 5 0.007 and p <0.001, respectively) by Kaplan-Meier analysis. However, CHOP was correlated with high tumor stage (p 5 0.038) and shorter survival (p 5 0.012). Expression of GRP78 and Beclin-1 was positively correlated (p 5 0.006). Our study showed that the expression of GRP78, CHOP, Beclin-1 and LC3 in lung cancer and its relation with clinicopathologic factors and patients survival. These results suggest that GRP78, CHOP and Beclin-1 may play an important role in tumorigenesis of lung AC and may serve as new prognostic indicators for outcome of the patients with NSCLC.

The tumor-to-tumor metastasis is a rare event. The lung tumors are the most common donor tumors in tumor-to-tumor metastasis, but are exceedingly rare as a recipient. Here, we report a case of papillary thyroid carcinoma (PTC) metastasizing to adenocarcinoma in situ (AIS, formerly bronchioloalveolar carcinoma) of the lung in a 44-year-old woman who underwent total thyroidectomy for PTC 8 years ago. To the best of our knowledge, the present case is the first case reporting on PTC metastasized to AIS. A review of the relevant literature is presented.

Regulated intramembrane proteolysis of epithelial cell adhesion molecule (EpCAM) results in shedding of the extracellular domain (EpEX) and release of the intra-cellular domain (EpICD) into the cytoplasm. Released EpICD associates with FHL2, β-catenin and Lef-1 to form a nuclear complex and triggers oncogenic signaling. This study was conducted to examine the nuclear expression of EpICD in hepatocellular carcinoma (HCC) and to assess the role of EpICD in HCC. EpICD immunoexpression was examined in 100 cases of HCC using tissue microarrays and correlated with clinicopathological parameters. We also examined the role of EpICD in HCC using EpICD cDNA transfected HCC cell line and EpCAM silenced HCC cell line by small interfering RNA (siRNA). Nuclear expression of EpICD was observed in 19 of 100 (19%) cases. Nuclear expression of EpICD significantly correlated with nuclear expression of β-catenin, and Ki-67 labeling index. In addition, nuclear expression of EpICD was associated with higher histologic grade and advanced T category. Forced overexpression of EpICD in the HCC cell significantly increased the cell proliferation, migration and invasion. The overexpression of EpICD also increased the expression levels of the active form of β-catenin and c-myc and cyclin D1. In contrast, downregulation of EpCAM by siRNA decreased the cell proliferation, migration, invasion and the expression of active form of β-catenin, c-myc and cyclin D1. Our present data suggest that EpICD plays important roles in HCC progression by modulating expression of target genes of EpCAM.

BackgroundHigh-risk human papillomavirus (HR-HPV) infection and abnormal p53 expression are closely involved in carcinogenesis of squamous cell carcinoma (SqCC) of uterine cervix. Recent studies have suggested that virus-induced endoplasmic reticulum (ER) stress modulates various cell survival and cell death signaling pathways. The C/EBP homologous protein (CHOP) is associated with ER stress-mediated apoptosis and is also involved in carcinogenesis of several human cancers. We hypothesized that CHOP is involved in the carcinogenesis of uterine cervical cancer in association with HR-HPV and/or p53.MethodsImmunohistochemistry was used to analyze CHOP and p53 protein expression of tissue sections from 191 patients with invasive cancer or preinvasive lesions of the uterine cervix (61 cases of SqCC, 66 cases of cervical intraepithelial neoplasia [CIN] III, and 64 cases of CIN I).ResultsCHOP was expressed in 59.4% of CIN I, 48.5% of CIN III, and 70.5% of SqCC cases. It was also significantly more frequent in invasive SqCC than in preinvasive lesions (p=0.042). Moreover, CHOP expression significantly correlated with HR-HPV infection and p53 expression (p=0.009 and p=0.038, respectively).ConclusionsOur results suggest that CHOP is involved in the carcinogenesis of the uterine cervix SqCC via association with HR-HPV and p53.