Conditionally reprogrammed cells (CRC) methodology does not allow the in vitro expansion of patient-derived primary and metastatic lung cancer cells.

Availability of tumor and non-tumor patient-derived models would promote the development of more effective therapeutics for non-small cell lung cancer (NSCLC). Recently, conditionally reprogrammed cells (CRC) methodology demonstrated exceptional potential for the expansion of epithelial cells from patient tissues. However, the possibility to expand patient-derived lung cancer cells using CRC protocols is controversial. Here, we used CRC approach to expand cells from non-tumoral and tumor biopsies of patients with primary or metastatic NSCLC as well as pulmonary metastases of colorectal or breast cancers. CRC cultures were obtained from both tumor and non-malignant tissues with extraordinary high efficiency. Tumor cells were tracked in vitro through tumorigenicity assay, monitoring of tumor-specific genetic alterations and marker expression. Cultures were composed of EpCAM+ lung epithelial cells lacking tumorigenic potential. NSCLC biopsies-derived cultures rapidly lost patient-specific genetic mutations or tumor antigens. Similarly, pulmonary metastases of colon or breast cancer generated CRC cultures of lung epithelial cells. All CRC cultures examined displayed epithelial lung stem cell phenotype and function. In contrast, brain metastatic lung cancer biopsies failed to generate CRC cultures. In conclusion, patient-derived primary and metastatic lung cancer cells were negatively selected under CRC conditions, limiting the expansion to non-malignant lung epithelial stem cells from either tumor or non-tumor tissue sources. Thus, CRC approach cannot be applied for direct therapeutic testing of patient lung tumor cells, as the tumor-derived CRC cultures are composed of (non-tumoral) airway basal cells.

Epstein-Barr virus (EBV) positive classical Hodgkin lymphoma of Iraqi children: an immunophenotypic and molecular characterization of Hodgkin/Reed-Sternberg cells.

BACKGROUND: Classical Hodgkin lymphoma (cHL) in children is often associated with EBV infection, more commonly in developing countries. PROCEDURE: Here we describe the histological, immunohistochemical, and molecular features of 57 cases of HL affecting Iraqi children under 14 years of age. RESULTS: Histologically, 51 cases were classified as cHL of Mixed Cellularity and Nodular Sclerosis subtypes (MC = 69%; NS = 31%), and 6 cases as Nodular Lymphocyte Predominant HL (NLP-HL). EBV infection of H/RS cells was demonstrated in 44 of 51 cases of cHL (86%), and was more common in MC than in NS (97% vs. 63%; P = 0.0025). The immunophenotypic profile of H/RS cells was similar in MC and NS, and was not influenced by EBV infection; H/RS cells were consistently positive for PAX-5 and to a lesser degree for other B cell markers including CD20/CD79a, OCT-2, and BOB-1. Clonal IGH rearrangements were detected in 14 of 38 cHL (37%), with no significant difference between MC and NS cases, and with no association with the EBV status. Oligoclonal/monoclonal TCRγ rearrangements were present in 28 of 38 cases (74%), suggestive of restricted T cell responses. CONCLUSIONS: Our findings indicate that cHL occurring in Iraqi children is characterized by immunohistochemical and molecular features undistinguishable from those present in cHL occurring elsewhere in the world. Moreover, the high incidence of EBV-infected H/RS cells and frequent occurrence of restricted T cell responses might be indicative of a defective local immune response perhaps related to the very young age of the children.

COX-2 is induced by HGF stimulation in Met-positive thyroid papillary carcinoma cells and is involved in tumour invasiveness.

Thyroid papillary carcinoma (TPC) cells express high levels of cytoplasmic cyclo-oxygenase 2 protein. Analysis of microdissected samples of the tumour and of the paired normal thyroid tissue confirmed that mRNA transcripts for cyclo-oxygenase 2 (COX-2) were significantly more numerous in the tumour (7.6 +/- 13-fold; p = 0.01). High levels of COX-2 mRNA were not associated with age, sex, tumour size or lymph node metastasis. COX-2 was not homogeneously expressed throughout the tumour, but was significantly higher at the tumour invasion front. Hepatocyte growth factor (HGF) can up-regulate the expression of COX-2 mRNA. A marked increase in COX-2 mRNA levels was observed in 8/8 primary TPC cultures after HGF stimulation (6.3 +/- 6-fold) and in two papillary carcinoma cell lines (TPC-1 and NPA). Specific involvement of the high-affinity HGF receptor (Met protein) was suggested by the observation that PHA-665752, an inhibitor of the catalytic activity of c-Met kinase, caused a 54% reduction of the hepatocyte growth factor-induced COX-2 up-regulation. The possibility that HGF-Met interactions also had a causative role in the up-regulation of COX-2 in vivo was investigated in 30 tumour samples, where it was found that there was a statistically significant correlation (p = 0.001, r = 0.85) in the levels of expression of MET and COX-2 RNAs. The biological role of COX-2 in TPC cells was investigated by treating the TPC cell lines with the specific COX-2 inhibitor NS-398. It was found that NS-398 treatment significantly reduced the migration (50-75%) and invasiveness (47-92%) of tumour cells, but did not alter cell proliferation. Our data suggest that the increased expression of Met protein in TPC cells has a role in up-regulating the expression of COX-2, which in turn contributes to the invasive capacity of TPC cells.

Left-sided early onset colorectal carcinomas: A sporadic neoplasm with aggressive behavior.

BACKGROUND: Early onset (≤50y) colorectal carcinomas (EO-CRCs) are increasing in incidence according to epidemiological data. We investigated clinical-pathological, molecular features and outcomes of 62 left sided EO-CRCs (EOLS-CRCs) and compared them to a group of late onset (≥65) LS-CRCs (LOLS-CRCs). MATERIALS AND METHODS: Samples were evaluated for pathological features and microsatellite instability (MSI). Overall survival (OS), disease free survival (DFS) and disease specific survival were evaluated in both groups. RESULTS: Five out 62 (8%) EOLS-CRCs showed MSI phenotype. Interestingly these cases were aged 26-39y. Most EOLS-CRCs present at advanced stage and this was statistically significant when compared to LOLS-CRCs. OS was better in EOLS-CRCs whilst DFS showed a worst profile in EOLS-CRCs either in low and high stages even though young patients were treated more often with adjuvant chemotherapy compared to older ones at the same disease stage. CONCLUSIONS: Most EOLS-CRCs are sporadic non Lynch, microsatellite stable (MSS) CRCs. Our data show that when compared with LOLS-CRCs the early group represents an aggressive disease with worst outcome underlining a possible different carcinogenic pathway.

A Case of Sinonasal Melanoma With Unusual Primary Exon 17 KIT D820G Mutation.

Sinonasal melanomas are rare neoplasms with poor prognosis that may harbor KIT and NRAS genes mutations. Molecular alterations represent possible targets of tailored therapeutic approaches. We describe the case of a 74-year-old patient with primary melanoma of the nasal cavity. Mutational analysis of KIT demonstrated a point missense mutation D820G in exon 17. This represents, to our knowledge, the first case of sinonasal melanoma harboring this specific KIT mutation. Although KIT mutations confer sensibility to thyrosine-kinase inhibitor, it has been proved that this is strongly dependent on the region in which this alteration occurs. Thus it seems very important to perform an accurate gene mutational analysis to provide a biological rationale to the tailored therapy.

Left-sided early-onset vs late-onset colorectal carcinoma: histologic, clinical, and molecular differences.

OBJECTIVES: Carcinomas of the left colon represent a neoplasm of older patients (late onset), but epidemiologic evidence has been showing an increasing incidence in patients 50 years or younger (early onset). In this study, we investigate pathologic and molecular features of early- and late-onset carcinoma of the left colon. METHODS: We selected 22 patients 50 years or younger and 21 patients 70 years or older with left-sided colorectal carcinoma (CRC). All samples were evaluated for pathologic features, microsatellite instability, and KRAS and BRAF mutations. Moreover, both groups were analyzed to identify CpG island methylator phenotype features and assessed with restriction landmark genome scanning (RLGS) to unveil differential DNA methylation patterns. RESULTS: Early-onset patients had advanced pathologic stages compared with late-onset patients (P = .0482). All cases showed a microsatellite stable profile and BRAF wild-type sequence. Early-onset patients (43%) more frequently had mutations at KRAS codon 12 compared with late-onset patients (14%) (P =.0413). RLGS showed that patients younger than 50 years who had CRC had a significantly lower percentage of methylated loci than did patients 70 years or older (P = .04124), and differential methylation of several genomic loci was observed in the two groups. CONCLUSIONS: Our results suggest that left-sided CRCs may present differential patterns of aberrant DNA methylation when they are separated by age.

Papillary carcinoma of the thyroid: high expression of COX-2 and low expression of KAI-1/CD82 are associated with increased tumor invasiveness.

BACKGROUND: We have previously demonstrated that expression of COX-2 is upregulated by hepatocyte growth factor in thyroid papillary carcinoma (TPC) cells and is associated with increased invasiveness of tumor cells. COX-2 upregulation was associated with downregulation of KAI-1/CD82, a metastasis suppressor molecule that has been associated with the metastatic potential of several solid tumors. In the present study, we have investigated the possibility that downregulation of KAI-1/CD82 may contribute to the invasiveness of papillary carcinoma cells. METHODS: Expression of KAI-1/CD82 and its relation to COX-2 levels were investigated in 6 primary cultures of TPC, in 2 tumor cell lines (TPC-1 and K1), and in 55 tumor samples of TPC. The biological role of KAI-1/CD82 in regulating tumor invasiveness was investigated in TPC cell lines and primary cultures transfected with a pCDNA3.1/Hygro.KAI-1; transfected cells were tested in functional studies of cell migration and invasiveness. Finally, the role of KAI-1/CD82 in influencing TPC metastasis was investigated in vivo using nu/nu mice injected with K1-transfected cells. RESULTS: We provide evidence that COX-2 and KAI-1/CD82 are inversely regulated in TPC primary cultures and in TPC-1 tumor cells. In fact, inhibition of COX-2 with NS398 is associated with a 2-9-fold upregulation of KAI-1/CD82 RNA. Moreover, a possible relation between COX-2 and KAI-1/CD82 was confirmed by the presence of a statistically significant inverse correlation in the expression of the two genes in 55 tumor samples of TPC (r = -0.513; p = 0.001). In 36 of 55 cases, tumor areas contained lower levels of KAI-1/CD82 RNA as compared with the corresponding normal tissue. Low expression of KAI-1/CD82 RNA in the tumor area was associated with extrathyroid extension of the disease in 16 of 19 cases (p < 0.04) and with lymph node metastasis in 11 of 14 cases (not significant). KAI-1/CD82 re-expression in tumor cells was associated with a significant decrease in their migratory (50-76% reduction) and invasive (46-65% reduction) capacity, even after hepatocyte growth factor stimulation. Finally, nu/nu mice injected with KAI-1/CD82-transfected K1 TPC cells developed fewer and smaller metastasis as compared with mice injected with vector-transfected K1 cells (p=0.016). CONCLUSION: Our findings raise the possibility that downregulation of KAI-1/CD82 in TPC cells is one of the molecular mechanisms regulating their invasive and metastatic potential.

Mek inhibition results in marked antitumor activity against metastatic melanoma patient-derived melanospheres and in melanosphere-generated xenografts.

One of the key oncogenic pathways involved in melanoma aggressiveness, development and progression is the RAS/BRAF/MEK pathway, whose alterations are found in most patients. These molecular anomalies are promising targets for more effective anti-cancer therapies. Some Mek inhibitors showed promising antitumor activity, although schedules and doses associated with low systemic toxicity need to be defined. In addition, it is now accepted that cancers can arise from and be maintained by the cancer stem cells (CSC) or tumor-initiating cells (TIC), commonly expanded in vitro as tumorspheres from several solid tumors, including melanoma (melanospheres). Here, we investigated the potential targeting of MEK pathway by exploiting highly reliable in vitro and in vivo pre-clinical models of melanomas based on melanospheres, as melanoma initiating cells (MIC) surrogates. MEK inhibition, through PD0325901, provided a successful strategy to affect survival of mutated-BRAF melanospheres and growth of wild type-BRAF melanospheres. A marked citotoxicity was observed in differentated melanoma cells regardless BRAF mutational status. PD0325901 treatment, dramatically inhibited growth of melanosphere-generated xenografts and determined impaired tumor vascularization of both mutated- and wild type-BRAF tumors, in the absence of mice toxicity. These results suggest that MEK inhibition might represent a valid treatment option for patients with both mutated- or wild type-BRAF melanomas, affecting tumor growth through multiple targets.

Differential modulation of uncoupling protein 2 in kidneys of stroke-prone spontaneously hypertensive rats under high-salt/low-potassium diet.

The stroke-prone spontaneously hypertensive rat (SHRsp) represents an animal model of increased susceptibility to high-salt diet-induced cerebral and renal vascular injuries. High blood pressure and genetic factors are viewed as major contributing factors. In high-salt-loaded SHRsp and stroke-resistant SHR animals, we determined blood pressure levels, degree of kidney lesions, renal uncoupling protein 2 (UCP2) gene and protein expression levels along with rattus norvegicus (rno)-microRNA (miR) 24 and 34a gene expression, nuclear factor-κB protein levels, and oxidative stress. In vitro, UCP2 gene silencing was performed in renal mesangial cells. We found more severe degree of renal damage in SHRsp at the end of 4-week high-salt dietary treatment as compared with stroke-resistant SHR, despite comparable blood pressure levels, along with increased rate of inflammation and oxidative stress. Kidney UCP2 gene and protein expression levels were significantly downregulated under high-salt diet in SHRsp, but not in stroke-resistant SHR. Differential UCP2 regulation was paralleled by differential expression of kidney rno-miR 24 and 34a, known to target UCP2 gene, in the 2 strains. UCP2 gene silencing in renal mesangial cells led to increased rate of reactive oxygen species generation, increased inflammation and apoptosis, reduced cell vitality, and increased necrosis. In conclusion, high-salt diet downregulates the antioxidant UCP2-dependent mechanism in kidneys of SHRsp, but not of stroke-resistant SHR. A parallel differential kidney miR regulation under high-salt diet in the 2 strains may contribute to the differential UCP2 modulation. UCP2 is a critical protein to prevent oxidative stress damage in renal mesangial cells in vitro.

Somatostatin receptor subtype 2 A (SSTR2A) and HER2 expression in gastric adenocarcinoma.

BACKGROUND: A possible anticancer role for somatostatin has been suggested. This study assessed the presence of somatostatin receptor subtype 2A (SSTR2A) in gastric cancer, correlating its expression with histological type, grade, human epidermal growth factor receptor 2 (HER2) expression, and disease outcome. MATERIALS AND METHODS: Gastric cancer tissues of 51 consecutive patients were collected for immunohistochemical assessment of both SSTR2A and HER2 expression. RESULTS: SSTR2A expression was observed in 38 (74.5%) cases. Prevalence of SSTR2A expression was significantly higher in well to moderately (G1-2) differentiated gastric cancer as compared to poorly (G3) differentiated tumors (96% vs. 52%; p<0.01), as well as in intestinal- than in diffuse-type cancer (97% vs. 20%; p<0.001). HER2 expression was positive in 18 (35%) patients, and it was associated with SSTR2A expression (r=0.50, p<0.001), being co-expressed in 17 (95%) out of 18 positive cases. RFS was significantly lower in patients with diffuse HER2 expression. CONCLUSION: This study demonstrated a co-localization between SSTR2A and HER2, potentially opening new therapeutic strategies for patients with gastric cancer.

Reliability of direct sequencing of EGFR: comparison between cytological and histological samples from the same patient.

The results of a recent study have shown the superiority of treatment with gefitinib or erlotinib in lung tumors positive for epidermal growth factor receptor (EGFR) mutation. As a consequence, the complete diagnosis of lung cancer cannot be limited to histotype classification, but should include a series of molecular biology analyses. In most cases, the diagnosis of lung cancer is performed on cytological specimens; therefore, there is a need to obtain a complete and reliable molecular diagnosis on cytologic specimens. Brushing, transbronchial needle aspiration (TBNA) and broncho alveolar lavage during fibro-bronchoscopy allow the sampling of the lung and the mediastinal lymph node. The aim of this study was to demonstrate that direct sequencing of exons 19 and 21 of EGFR in lung tumors, carried out on the cytological samples obtained through fibro-bronchoscopy, is as reliable as the same analysis carried out on a histological surgical sample obtained from the same individual. We considered 50 patients with a histological diagnosis of lung adenocarcinoma whose cytological samples, obtained by fibro-bronchoscopy and histological samples, obtained by surgical resection were available. A comparison of the sensitivity and reliability of the molecular biology analyses carried out on histological and cytological samples of the same patient was carried out. The combined mutation percentage of exons 19 and 21 of EGFR was 10%. The results of the analyses carried out on cytological samples matched those obtained from the histological samples. The feasibility of EGFR analysis on cytological samples has already been demonstrated in previous studies, however these studies referred to the method of fluorescence in situ hybridization, or did not perform any comparison between histological samples from the same patient; our work, on the other hand, shows that direct sequencing of exons 19 and 21 of the EGFR gene is feasible on fibro-bronchoscopy cytological samples with the same reliability offered by the histological samples obtained from the same patient.

Prognostic significance of 18q LOH in sporadic colorectal carcinoma.

Identification of molecular alterations with implication for prognosis and sensibility to chemotherapeutic agents represents a great challenge in colorectal carcinoma treatment. Controversial results have been reported on prognostic value of chromosome 18q loss. Ninety-seven unselected patients with sporadic colorectal carcinoma Stage II and III were investigated for loss of heterozygosity at 18q D18S58 and D18S61 loci. Molecular alterations were correlated with clinicopathological data and survival. 18q loss of heterozygosity (LOH) was present in 56 per cent cases of carcinoma and was not related either to the clinicopathological characteristics of the patients or to prognosis. However, patients with LOH at locus D18S61 showed a more favorable prognosis. This finding was especially true for Stage II and untreated carcinoma. Survival was not influenced by the status of D18S58 locus. In our series, LOH at chromosome 18q does not seem to predict an unfavorable outcome. It seems of special interest the benefit that D18S61 loss of heterozygosity confers to untreated patients and patients with Stage II colon carcinoma.