Exosomal glypican-1 discriminates pancreatic ductal adenocarcinoma from chronic pancreatitis

BACKGROUND AND AIMS

Pancreatic ductal adenocarcinoma (PDAC) diagnosis can be difficult in a chronic pancreatitis (CP) background, especially in its mass forming presentation. We aimed to assess the accuracy of glypican-1-positive circulating exosomes (GPC1+crExos) to distinguish PDAC from CP versus the state-of-the-art CA 19-9 biomarker.

METHODS

This was a unicentric prospective cohort. Endoscopic ultrasound with fine-needle aspiration or biopsy and blood tests (GPC1+crExos and serum CA 19-9) were performed.

RESULTS

The cohort comprised 60 PDAC and 29 CP (7 of which mass forming - MF) patients. Median levels of GPC1+crExos were significantly higher in PDAC (99.7%) versus CP (28.4%; p<0.0001) with an AUROC of 0.96 with 98.3% sensitivity and 86.2% specificity for a cut-off of 45.0% (p<0.0001); this outperforms CA 19-9 AUROC of 0.82 with 78.3% sensitivity and 65.5% specificity at a cut-off of 37 U/mL (p<0.0001). The superiority of% GPC1+crExos over CA 19-99 in differentiating PDAC from CP was observed in both early (stage I) and advanced tumors (stages II-IV).

CONCLUSION

Levels of GPC1+crExos coupled to beads enable differential diagnosis between PDAC and CP including its mass-forming presentation.

The tissue expression pattern of CA 19.9 is associated with oncological features in medullary thyroid carcinoma

PURPOSE

Elevated serum levels of carbohydrate antigen 19.9 (CA19.9), a well-established tumor marker in pancreatic neoplasms, has been proposed as a prognostic marker of tumor aggressiveness in medullary thyroid carcinoma (MTC). A hypothesis of C-cell dedifferentiation has been raised. Here, we evaluated the expression of CA19.9 and CD133, a stem cell marker, in MTC tissues.

METHODS

MTC samples from patients attending a university-based hospital were evaluated for CA19.9 and CD133 expression by immunohistochemistry. Clinical data were retrieved from medical records.

RESULTS

Tumor specimens from 70 MTC patients (57.1% hereditary) were evaluated. The age at diagnosis was 36.1 ± 16.3 years, and 58.6% were female; 53% of patients had cervical and 20% distant metastases. CA19.9 staining was detected in 87% of the samples, but no association was observed with biochemical markers, tumor size, local or distant metastases (All P > 0.05). Remarkable, CA19.9 expression was higher in the metastasis than in primary tumor samples (P = 0.0002). CD133 was expressed in 90.5% samples, but no correlation was found with CA19.9. Interestingly, we identified three distinct expression patterns to CA19.9: individual, focal, and diffuse cells. Sporadic MTC was associated with the individual cell pattern (70.6%), while the hereditary form with the focal expression pattern (63.9%; P = 0.04). Remarkably, the diffuse pattern was associated with larger tumor size and distant metastases (P = 0.032).

CONCLUSIONS

The majority of samples stained for CA19.9, suggesting it is an MTC cell-intrinsic feature. Three distinct expression patterns were identified, which were associated with the hereditary or sporadic form, larger tumor size, and presence of metastases.

Serum CA 19.9 Levels in Patients With Benign and Malignant Disease: Correlation With the Serum Protein Electrophoretic Pattern

AIM

To confirm that the carbohydrate antigen 19.9 (CA 19.9) protein can be evaluated by determining changes in the β2 zone in protein electrophoresis.

MATERIALS AND METHODS

A total of 75 patients (64 with cancer, 11 with benign diseases) with abnormal serum CA 19.9 level were included.

RESULTS

Patients with cancer had significantly higher serum CA 19.9 concentrations than those with benign diseases (p<0.001). Similar CA 19.9 levels were observed in patients with normal (median 1129 U/ml), weakly positive (median 699 U/ml) and positive (2333 U/ml) β2 fraction in protein electrophoresis. In contrast, changes in the protein pattern of the β2 fraction were related to an inflammatory pattern with significantly higher C-reactive protein concentration (p<0.0001), independently of serum CA 19.9 level.

CONCLUSION

The intensity of the β2 fraction in protein electrophoresis is related to inflammation and not to CA 19.9 in patients with cancer or other diseases.

Relationship Between CA 19.9 and the Lewis Phenotype: Options to Improve Diagnostic Efficiency

BACKGROUND/AIM

Approximately 10% of patients are unable to synthesize CA 19.9 (Lewis-negative), and these results are erroneously considered false-negatives. The aim of this study was to confirm that CA 19.9 cannot be detected by immunoassays in Lewis-negative patients.

MATERIALS AND METHODS

CA 19.9 levels were measured by immunological assays and Lewis phenotype was determined by the haemagglutination reaction.

RESULTS

Patients with Lewis phenotype (a+b-) or (a-b+) had significantly higher CA 19.9 levels than Lewis-negative patients with active cancer (p<0.001), no-evidence of disease (NED) patients (p<0.001) or patients with benign disease (p<0.001). Ninenty-four percent of patients (33/35) with undetectable CA 19.9 had a Lewis-negative phenotype. Additionally, 94.7% (34/36) of patients with Lewis-negative phenotypes had undetectable CA 19.9 serum levels.

CONCLUSION

Patients with undetectable CA 19.9 serum levels tend to be Lewis-negative, and CA 19.9 is not useful in diagnosis or follow-up.

Gastric Cancer Cell Glycosylation as a Modulator of the ErbB2 Oncogenic Receptor

Aberrant expression and hyperactivation of the human epidermal growth factor receptor 2 (ErbB2) constitute crucial molecular events underpinning gastric neoplastic transformation. Despite ErbB2 extracellular domain being a well-known target for glycosylation, its glycosylation profile and the molecular mechanisms through which it actively tunes tumorigenesis in gastric cancer (GC) cells remain elusive. We aimed at disclosing relevant ErbB2 glycan signatures and their functional impact on receptor's biology in GC cells. The transcriptomic profile of cancer-relevant glycosylation enzymes, and the expression and activation of the ErbB receptors were characterized in four GC cell lines. Cellular- and receptor-specific glycan profiling of ErbB2-overexpressing NCI-N87 cells unveiled a heterogeneous glycosylation pattern harboring the tumor-associated sialyl Lewis a (SLe^a) antigen. The expression of SLe^a and key enzymes integrating its biosynthetic pathway were strongly upregulated in this GC cell line. An association between the expression of ERBB2 and FUT3, a central gene in SLe^a biosynthesis, was disclosed in GC patients, further highlighting the crosstalk between ErbB2 and SLe^a expression. Moreover, cellular deglycosylation and CA 19.9 antibody-mediated blocking of SLe^a drastically altered ErbB2 expression and activation in NCI-N87 cells. Altogether, NCI-N87 cell line constitutes an appealing in vitro model to address glycan-mediated regulation of ErbB2 in GC.

Clinical significance of serum carbohydrate antigen 19.9 and duke pancreatic monoclonal antigen type 2 for the prediction of hematogenous metastases in patients with pancreatic ducal adenocarcinoma

OBJECTIVES

The aim of the present study was to investigate the effectiveness of serum carbohydrate antigen (CA) 19.9 and duke pancreatic monoclonal antigen type 2 (DUPAN-2) levels in the prediction of early hematogenous metastases and as indicators of neoadjuvant therapy in patients with pancreatic ductal adenocarcinoma (PDAC).

METHODS

Of the 293 enrolled PDAC patients, 61 had hematogenous metastases at the initial evaluation. One hundred and twenty patients without metastases underwent surgical resection. Of the 120 patients who underwent surgical resection, 45 underwent preoperative treatment and 29 developed early hematogenous metastases within 1 year after the surgery. In patients who underwent preoperative therapy, serum CA 19.9 and DUPAN-2 levels were measured within 2 weeks before the preoperative therapy and the subsequent surgery.

RESULTS

The elevated serum CA 19.9 and DUPAN-2 levels were significantly associated with hematogenous metastasis at initial evaluation and early hematogenous metastasis after surgery. The rate of early hematogenous metastasis and overall survival (OS) in patients with high CA 19.9 and/or high DUPAN-2 (CA 19.9 > 200 U/mL and/or DUPAN-2 >300 U/mL) were 46.3% and 18 months, respectively, whereas the metastatic rate and OS in patients with low CA 19.9 and DUPAN-2 were 12.7% and 37.5 months, respectively. Furthermore, in patients with high CA 19.9 and/or high DUPAN-2, preoperative therapy significantly reduced the rate of early hematogenous metastasis and prolonged the OS.

CONCLUSIONS

Serum CA 19.9 and DUPAN-2 levels are useful predictors of early hematogenous metastasis and indicators for effectiveness of neoadjuvant therapy in PDAC patients.

Prognostic factors and sites of metastasis in unresectable locally advanced pancreatic cancer

Due to differences in natural history and therapy, clinical trials of patients with advanced pancreatic cancer have recently been subdivided into unresectable locally advanced pancreatic cancer (LAPC) and metastatic disease. We aimed to evaluate prognostic factors in LAPC patients who were treated with first-line chemotherapy and describe patterns of disease progression. Patients with LAPC who initiated first-line palliative chemotherapy, 2001–2011 at the BC Cancer Agency were included. A retrospective chart review was conducted to identify clinicopathologic variables, treatment, and subsequent sites of metastasis. Kaplan–Meier and Cox-regression survival analyses were performed. A total of 244 patients were included in this study. For the majority of patients (94.3%), first-line therapy was single-agent gemcitabine. About 144 (59%) patients developed distant metastatic disease and the most frequent metastatic sites included peritoneum/omentum (42.3%), liver (41%), lungs (13.9%), and distant lymph nodes (9%). Median overall survival (OS) for the entire cohort was 11.7 months (95% CI, 10.6–12.8). Development of distant metastases was associated with significantly inferior survival (HR 3.56, 95% CI 2.57–4.93), as was ECOG 2/3 versus 0/1 (HR 1.69, 95% CI 1.28–2.23), CA 19.9 > 1000 versus ≤1000 (HR 1.59, 95% CI 1.19–2.14) and female gender, (HR 1.57, 95% CI 1.19–2.08). In this population-based study, 41% of LAPC patients treated with first-line chemotherapy died without evidence of distant metastases. Prognostic factors for LAPC were baseline performance status, elevated CA 19.9, gender, and development of distant metastasis. Results highlight the heterogeneity of LAPC and the importance of locoregional tumor control.