COL11A1/(pro)collagen 11A1 expression is a remarkable biomarker of human invasive carcinoma-associated stromal cells and carcinoma progression

The COL11A1 human gene codes for the α1 chain of procollagen 11A1 and mature collagen 11A1, an extracellular minor fibrillar collagen. Under regular conditions, this gene and its derived products are mainly expressed by chondrocytes and mesenchymal stem cells as well as osteoblasts. Normal epithelial cells and quiescent fibroblasts from diverse locations do not express them. Mesenchyme-derived tumors and related conditions, such as scleroderma and keloids, are positive for COL11A1/(pro)collagen 11A1 expression, as well as high-grade human gliomas/glioblastomas. This expression is almost absent in benign pathological processes such as breast hyperplasia, sclerosing adenosis, idiopathic pulmonary fibrosis, cirrhosis, pancreatitis, diverticulitis, and inflammatory bowel disease. By contrast, COL11A1/(pro)collagen 11A1 is highly expressed by activated stromal cells of the desmoplastic reaction of different human invasive carcinomas, and this expression is correlated with carcinoma aggressiveness and progression, and lymph node metastasis. COL11A1 upregulation has been shown to be associated to TGF-β1, Wnt, and Hh signaling pathways, which are especially active in cancer-associated stromal cells. At the front of invasive carcinomas, neoplastic epithelial cells, putatively undergoing epithelial-to-mesenchymal transition, and carcinoma-derived cells with highly metastatic capabilities, can express COL11A1. Thus, in established metastases, the expression of COL11A1/(pro)collagen 11A1 could rely on both the metastatic epithelial cells and/or the accompanying activated stromal cells. COL11A1/(pro)collagen 11A1 expression is a remarkable biomarker of human carcinoma-associated stromal cells and carcinoma progression.

Histological grade (HG) in invasive ductal carcinomas of the breast of less than 1 cm: clinical and biological associations during progression from HG1 to HG3

AIM

To study the clinical and biological (cellular proliferation and hormone-dependence) associations during the progression of histological grade (HG), from HG1 to HG3, in invasive ductal carcinomas of the breast (IDC) <1 cm.

PATIENTS AND METHODS

The study group included 119 women with IDCs ≤1 cm, aged between 27 and 88 years (median=61 years). The parameters analyzed were: histological grade (HG1: 52; HG2: 45; HG3: 22); axillary lymph node involvement (N); distant metastasis (M); and immunohistochemical expression of estrogen (ER), progesterone (PR) and androgen (AR) receptors, and Ki67, p53 and B-cell lymphoma 2 (BCL2).

RESULTS

Compared to HG3 tumors, HG1s exhibited an increased expression of ER, AR and BCL2, as well as lower expression of p53 and Ki67. In HG1 tumors, significant (p<0.05) associations were found between ER and PR (positive), ER and p53 (negative), ER and Ki67 (negative), PR and AR (positive), PR and p53 (negative), AR and p53 (negative), p53 and BCL2 (negative), and between BCL2 and Ki67 (negative). HG3s only showed significant (p<0.05) associations between ER and Ki-67 (negative) and between BCL2 or Ki-67 (negative). Only two significant relationships (ER-Ki67 and BCL2-Ki67) persisted in all three grades.

CONCLUSION

Our results lead us to the following conclusions: i) compared HG1, HG3 ductal carcinomas exhibited decreased expression of ER, AR and BCL2 and increased expression of p53 and Ki67; and ii) only two significant and negative relations (ER-Ki67 and BCL2-Ki67) persisted in all three grades.

Validation of COL11A1/procollagen 11A1 expression in TGF-β1-activated immortalised human mesenchymal cells and in stromal cells of human colon adenocarcinoma

Background

The human COL11A1 gene has been shown to be up-regulated in stromal cells of colorectal tumours, but, so far, the immunodetection of procollagen 11A1, the primary protein product of COL11A1, has not been studied in detail in human colon adenocarcinomas. Some cancer-associated stromal cells seem to be derived from bone marrow mesenchymal cells; the expression of the COL11A1 gene and the parallel immunodetection of procollagen 11A1 have not been evaluated in these latter cells, either.

Methods

We used quantitative RT-PCR and/or immunocytochemistry to study the expression of DES/desmin, VIM/vimentin, ACTA2/αSMA (alpha smooth muscle actin) and COL11A1/procollagen 11A1 in HCT 116 human colorectal adenocarcinoma cells, in immortalised human bone marrow mesenchymal cells and in human colon adenocarcinoma-derived cultured stromal cells. The immunodetection of procollagen 11A1 was performed with the new recently described DMTX1/1E8.33 mouse monoclonal antibody. Human colon adenocarcinomas and non-malignant colon tissues were evaluated by immunohistochemistry as well. Statistical associations were sought between anti-procollagen 11A1 immunoscoring and patient clinicopathological features.

Results

Procollagen 11A1 was immunodetected in human bone marrow mesenchymal cells and in human colon adenocarcinoma-associated spindle-shaped stromal cells but not in colon epithelial or stromal cells of the normal colon. This immunodetection paralleled, in both kinds of cells, that of the other mesenchymal-related biomarkers studied: vimentin and alpha smooth muscle actin, but not desmin. Thus, procollagen 11A1⁺ adenocarcinoma-associated stromal cells are similar to “activated myofibroblasts”. In the series of human colon adenocarcinomas here studied, a high procollagen 11A1 expression was associated with nodal involvement (p = 0.05), the development of distant metastases (p = 0.017), and advanced Dukes stages (p = 0.047).

Conclusion

The immunodetection of procollagen 11A1 in cancer-associated stromal cells could be a useful biomarker for human colon adenocarcinoma characterisation.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2407-14-867) contains supplementary material, which is available to authorized users.

Common non-synonymous SNPs associated with breast cancer susceptibility: findings from the Breast Cancer Association Consortium

Candidate variant association studies have been largely unsuccessful in identifying common breast cancer susceptibility variants, although most studies have been underpowered to detect associations of a realistic magnitude. We assessed 41 common non-synonymous single-nucleotide polymorphisms (nsSNPs) for which evidence of association with breast cancer risk had been previously reported. Case-control data were combined from 38 studies of white European women (46 450 cases and 42 600 controls) and analyzed using unconditional logistic regression. Strong evidence of association was observed for three nsSNPs: ATXN7-K264R at 3p21 [rs1053338, per allele OR = 1.07, 95% confidence interval (CI) = 1.04-1.10, P = 2.9 × 10(-6)], AKAP9-M463I at 7q21 (rs6964587, OR = 1.05, 95% CI = 1.03-1.07, P = 1.7 × 10(-6)) and NEK10-L513S at 3p24 (rs10510592, OR = 1.10, 95% CI = 1.07-1.12, P = 5.1 × 10(-17)). The first two associations reached genome-wide statistical significance in a combined analysis of available data, including independent data from nine genome-wide association studies (GWASs): for ATXN7-K264R, OR = 1.07 (95% CI = 1.05-1.10, P = 1.0 × 10(-8)); for AKAP9-M463I, OR = 1.05 (95% CI = 1.04-1.07, P = 2.0 × 10(-10)). Further analysis of other common variants in these two regions suggested that intronic SNPs nearby are more strongly associated with disease risk. We have thus identified a novel susceptibility locus at 3p21, and confirmed previous suggestive evidence that rs6964587 at 7q21 is associated with risk. The third locus, rs10510592, is located in an established breast cancer susceptibility region; the association was substantially attenuated after adjustment for the known GWAS hit. Thus, each of the associated nsSNPs is likely to be a marker for another, non-coding, variant causally related to breast cancer risk. Further fine-mapping and functional studies are required to identify the underlying risk-modifying variants and the genes through which they act.

Overexpression of proCOL11A1 as a stromal marker of breast cancer

BACKGROUND

Our previous studies demonstrated the expression of procollagen11A1 in fibroblasts of pancreatic cancer desmoplasia and the lack of expression in fibroblasts of pancreatitis by means of the polyclonal antibody (anti-proCOL11A1 pAb) we generated. In a similar way, we decided to compare the expression of procollagen11A1 in fibroblasts of infiltrating ductal carcinoma of the breast and fibroblasts of benign sclerosing lesions of the breast, in order to validate the anti-proCOL11A1 pAb in this setting and to study how proCOL11A1 expression relates to other prognostic and predictive factors, as well as to survival.

METHODS

45 core biopsies of sclerosing adenosis and 50 core biopsies of infiltrating ductal carcinoma of the breast were stained with anti-proCOL11A1 pAb, a polyclonal antibody highly specific to the less homologous fraction of proCOL11A1 (in comparison with proCOL5A1 and proCOL11A2). In addition, the expression of the proCOL11A1 gene was measured by RT-qPCR. On the other hand, the expression of proCOL11A1 was compared to the expression of estrogenic receptors, progestagen receptors, the state of the epidermal growth factor receptor 2 (HER2), the histologic grade and the stage of the disease. We also compared the immunohistochemical expression of proCol11A1 to the disease-free interval, and to overall survival.

RESULTS

The immunohistochemical analysis showed that proCOL11A1 was expressed in 100% of infiltrating ductal carcinomas, but only focally expressed in 2.2% (1 case) of sclerosing adenosis, in agreement with RT-qPCR results. ProCOL11A1 expression did not prove to have a prognostic value in relation to the disease-free interval or to overall survival in infiltrating ductal carcinoma.

CONCLUSION

The anti-proCOL11A1 pAb is a stromal marker for breast cancer and the expression of proCOL11A1 does not seem to have a prognostic value in infiltrating ductal carcinoma of the breast.

FGF receptor genes and breast cancer susceptibility: results from the Breast Cancer Association Consortium

BACKGROUND

Breast cancer is one of the most common malignancies in women. Genome-wide association studies have identified FGFR2 as a breast cancer susceptibility gene. Common variation in other fibroblast growth factor (FGF) receptors might also modify risk. We tested this hypothesis by studying genotyped single-nucleotide polymorphisms (SNPs) and imputed SNPs in FGFR1, FGFR3, FGFR4 and FGFRL1 in the Breast Cancer Association Consortium.

METHODS

Data were combined from 49 studies, including 53 835 cases and 50 156 controls, of which 89 050 (46 450 cases and 42 600 controls) were of European ancestry, 12 893 (6269 cases and 6624 controls) of Asian and 2048 (1116 cases and 932 controls) of African ancestry. Associations with risk of breast cancer, overall and by disease sub-type, were assessed using unconditional logistic regression.

RESULTS

Little evidence of association with breast cancer risk was observed for SNPs in the FGF receptor genes. The strongest evidence in European women was for rs743682 in FGFR3; the estimated per-allele odds ratio was 1.05 (95% confidence interval=1.02-1.09, P=0.0020), which is substantially lower than that observed for SNPs in FGFR2.

CONCLUSION

Our results suggest that common variants in the other FGF receptors are not associated with risk of breast cancer to the degree observed for FGFR2.

Overexpression of COL11A1 by cancer-associated fibroblasts: clinical relevance of a stromal marker in pancreatic cancer

BACKGROUND

The collagen11A1 (COL11A1) gene is overexpressed in pancreatic cancer. The expression of COL11A1 protein could be involved in desmoplastic events in pancreatic cancer, but an antibody that specifically stains the COL11A1 protein is not currently available.

METHODS AND FINDINGS

A total of 54 pancreatic ductal adenocarcinomas (PDAC), 23 chronic pancreatitis (CP) samples, and cultured peritumoral stromal cells of PDAC (passages 3-6) were studied. Normal human pancreas tissue samples were obtained through a cadaveric organ donation program. 1) Validation of COL11A1 gene overexpression by q-RT-PCR.

FINDINGS

the expression of COL11A1 gene is significantly increased in PDAC samples vs. normal and CP samples. 2) Analysis of COL11A1 by immunohistochemistry using highly specific anti-proCOL11A1 antibodies.

FINDINGS

anti-proCOL11A1 stains stromal cells/cancer-associated fibroblasts (CAFs) of PDAC but it does not stain chronic benign condition (chronic pancreatitis) stromal cells, epithelial cells, or normal fibroblasts. 3) Evaluation of the discrimination ability of the antibody.

FINDINGS

anti-proCOL11A1 immunostaining accurately discriminates between PDAC and CP (AUC 0.936, 95% CI 0.851, 0.981). 4) Phenotypic characterization of proCOL11A1+ stromal cells co-staining with mesenchymal, epithelial and stellate cell markers on pancreatic tissue samples and cultured peritumoral pancreatic cancer stromal cells.

FINDINGS

ProCOL11A1+ cells present co-staining with mesenchymal, stellate and epithelial markers (EMT phenotype) in different proportions.

CONCLUSIONS/SIGNIFICANCE

Detection of proCOL11A1 through immunostaining with this newly-developed antibody allows for a highly accurate distinction between PDAC and CP. Unlike other available antibodies commonly used to detect CAFs, anti-proCOL11A1 is negative in stromal cells of the normal pancreas and almost absent in benign inflammation. These results strongly suggest that proCOL11A1 is a specific marker for CAFs, and thus, anti-proCOL11A1 is a powerful new tool for cancer research and clinical diagnostics.

Characterization of a novel mouse monoclonal antibody, clone 1E8.33, highly specific for human procollagen 11A1, a tumor-associated stromal component

A novel IgG1, κ mouse monoclonal antibody (clone 1E8.33) to human procollagen 11A1 has been generated. This antibody is poorly mutated, essentially in germ line configuration; its complementarity determining regions (CDRs) are especially rich in tyrosine and serine residues. The epitope recognized is encompassed in the YNYGTMESYQTEAPR amino acid stretch within the variable region of human procollagen 11A1. Human procollagens 5A1 and 11A1 are very similar. However, this antibody does not cross-react with human procollagen 5A1. In human breast tumors, only the activated peritumoral myofibroblasts show a strong intracytoplasmic staining with this antibody. As procollagen 11A1 is overexpressed in the stroma of human tumors with desmoplastic reaction, this antibody represents a valuable tool for diagnostic purposes.

Effect of aluminium on calcium-sensing receptor expression, proliferation, and apoptosis of parathyroid glands from rats with chronic renal failure

BACKGROUND

To assess the effect of aluminium on the calcium-sensing receptor expression, proliferation, and apoptosis in parathyroid glands from rats with chronic renal failure, 2(1/2)-month-old male Wistar rats were 7/8 nephrectomized.

METHODS

Eight weeks after surgery the rats were divided into two groups, one receiving intraperitoneal AlCl3 for 8 weeks and the other receiving intraperitoneal placebo. Serum Al, Ca, P, creatinine, and PTH were measured. Parathyroid glands were removed, formaldehyde-fixed, and paraffin-embedded. Calcium-sensing receptor and proliferation were detected by immunohistochemistry and apoptosis by TUNEL and propidium iodide uptake.

RESULTS

At the end of the study, despite higher levels of serum P in the aluminium group (6.27 +/- 0.63 vs. 5.56 +/- 0.58 mg/dL; P = 0.045), serum PTH was lower (89.6 +/- 57.7 vs. 183.1 +/- 123.8 pg/mL; P = 0.059). No significant differences were found in the calcium-sensing receptor expression between groups (aluminium: 27.1 +/- 7.6; placebo: 25.4 +/- 3.5 RU). Rats receiving aluminium showed a significantly lower cell proliferation rate than the control rats (0.54 +/- 0.69 vs. 4.43 +/- 3.10 cells/mm2; P = 0.003). No apoptotic events were detected.

CONCLUSION

Aluminium was able to reduce the cell proliferation of the parathyroid glands. Due to the low apoptosis rate, however, it was not possible to find any change. Aluminium had no effect on the calcium-sensing receptor expression.

Aluminum-induced osteogenesis in osteopenic rats with normal renal function

Previous studies have shown a different effect of aluminum (Al) on bone metabolism in animals with chronic renal failure and conversely, positive osteogenic effects in animals with normal renal function. The aim of this study was to evaluate the effect of aluminum on bone metabolism in osteopenic rats. We studied male Wistar rats with severe osteopenia induced by adding NH4Cl (2%) to the drinking water over a 6-month period. The rats were divided into two groups and followed for 4 months. The Aluminum group (G1) received AlC13 intraperitoneally (10 mg/kg/5 days/week) (n = 8); the Control group (G2) did not receive any treatment after stopping the administration of NH4Cl (n = 5). In all animals we measured biochemical markers (serum Ca, P, Cr, Al, osteocalcin, hydroxyproline) as well as bone mineral density and bone histomorphometry (BV/TV, CTh, ObS/BS, OTh, and NOc/TV). Bone aluminum content, measured by atomic absorption spectrometry, was 101.6 +/- 13 microg/g in the Al overloaded group and 1.31 +/- 0.14 in controls. Bone mineral density, evaluated by dual X-ray absorptiometry (DXA) at the proximal extremity of the tibia was significantly higher in G1 (0.292 +/- 0.01 g/cm2 versus 0. 267 +/- 0.02 g/cm2). No significant differences were found between the biochemical markers. In the histomorphometric parameters we observed significant differences in G1 compared with G2: an increase in BV/TV (18.59 +/- 5.6 versus 7.69 +/- 3.08%) and in CTh (0.52 +/- 0.06 versus 0.36 +/- 0.07 mm) with a moderate increment of the osteoid thickness (14.05 +/- 4.72 versus 5.25 +/- 0.9 microm) (P < 0. 05). Changes in others parameters and the relationship between biochemical parameters of bone remodeling, Al, and histology were analyzed. These findings indicate that in rats with normal renal function, Al is able to induce bone formation even when osteopenia is present.

[Chronic renal insufficiency and secondary hyperparathyroidism in rats. Biochemical and histological evaluation]

Chronic renal failure (CRF) in rats (surgical nephrectomy, 5/6) as well as its derived bone lesions have been studied. Eighty-five male Wistar rats were used, to which chronic renal failure was induced in 1 or 2 surgical times, the parameters of renal function in basal conditions and at different times after surgery being determined. With the method used chronic renal failure is induced with values of creatinine clearance 2/3 times lower than the initial ones (p < 0.05), which stabilize at the 7th week. On the other hand the parathyroid hormone levels (PTH) in serum triple (from 125 +/- 49 to 395 +/- 191, p < 0.05), and a decrease in the tubular phosphate reabsorption is produced (p < 0.001). In bone histology an increase in resorption and bone formation is observed as well as paratrabecular fibrosis, all of which is compatible with the histological diagnosis of hyperparathyroidism. The model of surgical renal insufficiency with ablation of 5/6 of the renal mass, reduces renal function to 1/3 of the initial values after 7 weeks, this procedure having a 20% global mortality without differences being observed between the carrying out of nephrectomies in 1 or 2 surgical times. This degree of CRF was accompanied by secondary hyperparathyroidism both at the biochemical and histological levels, findings which are of great usefulness for future experimental studies.