Laminin-5 gamma2 chain expression as a possible determinant of tumor aggressiveness in T1 colorectal carcinomas

Vascular Invasion and Stromal S100A4 Expression at the Invasive Front of Colorectal Cancer are Novel Determinants and Tumor Prognostic Markers

Object: The aim of the present study was to investigate the clinicopathological characteristics and prognostic factors associated with sporadic colorectal cancer (CRC). We examined the clinicopathological findings and immunohistochemical expression of tumor prognostic markers at tumor budding sites to determine their predictive value for patient prognosis.

Materials and Methods: Immunohistochemical examination was performed by tissue microarray (TMA) of specimens from 106 patients with CRC. On hematoxylin and eosin (H&E)-stained tumor tissue slides, a representative area of tumor budding at the invasive front was selected for the construction of a TMA. Immunostaining for matrix metalloproteinase-7 (MMP7), the laminin-5 (ln-5) γ2 chain and S100A4 was performed to determine the association between patient survival and these markers.

Results: Clinicopathological variables were also assessed. Tumor location, histological type, degree of lymphatic invasion and vascular invasion, tumor stage, epithelial expression of S100A4, stromal cell expression of S100A4 and expression of the ln-5γ2 chain were associated with an increased risk of mortality. Five factors were retained in the multivariate logistic regression analysis. Specifically, the tumor location, degree of lymphatic invasion and vascular invasion, tumor stage and stromal cell expression of S100A4 remained significant predictors of patient survival after controlling for the other variables.

Conclusion: Vascular invasion and stromal expression of S100A4 in the tumor budding areas correlated with patient survival. Stromal immunostaining of S100A4 may be useful for identifying high-risk patients with advanced CRC.

Prognostic significance of circulating laminin gamma2 for early-stage non-small-cell lung cancer

Background

Laminin gamma2 (Ln-γ2) chain, a distinctive subunit of heterotrimeric laminin-332, is frequently upregulated in carcinomas and is of great importance in cell migration and invasion. Despite this, the status of circulating Ln-γ2 in lung cancer patients is still uncertain.

Patients and methods

In this retrospective study, serum samples from 538 all-stage (stages I–IV) patients with non-small-cell lung cancer (NSCLC) and 94 age-matched healthy volunteers were investigated by enzyme-linked immunosorbent assay. Data were statistically analyzed in combination with clinicopathological information.

Results

Circulating Ln-γ2 was markedly increased in NSCLC, even in stage I cases (P<0.01), reflecting the progression of lung cancer. Survival analysis on 370 eligible patients indicated that serum Ln-γ2-negative patients survived much longer compared with Ln-γ2-positive individuals (P=0.028), and it was especially the case for stage I (P<0.001), stage T1 (P=0.001), and stage N0 patients (P=0.038), all of whom represented early-stage cases. For the advanced patients, however, overall survivals were not significantly different among stages II–IV (P=0.830), stages T2–T4 (P=0.575), stages N1–N3 (P=0.669), and stage M1 (P=0.849). Cox analysis subsequently defined serum Ln-γ2 as an independent prognostic indicator of NSCLC, particularly for early-stage patients. Furthermore, we demonstrated the association of serum Ln-γ2 with smoking behavior, but its association with tumor progression and early prognostic significance were not altered in the nonsmoking cohort.

Conclusion

Our study demonstrated that elevation of circulating Ln-γ2 was an early-emerging event in NSCLC and was significantly associated with poor prognosis in NSCLC, especially for early-stage cases.

Laminin β3 expression as a prognostic factor and a predictive marker of chemoresistance in colorectal cancer

OBJECTIVE

Laminin-332, a marker of epithelial-mesenchymal transition, is composed of a heterotrimer of α3, β3 and γ2 chains that regulates cell adhesion and migration. This study aimed to disclose the respective clinical significance of laminin β3 immunoexpression in colorectal cancer as a prognostic factor and a predictive marker of chemoresistance.

METHODS

Tissue specimens from 323 Stage II and 232 Stage III colorectal cancer patients who underwent curative resection were assessed using laminin β3 immunostaining.

RESULTS

Among Stage III colorectal cancer patients, comparisons of 5-year disease-free survival rates revealed a poorer prognosis for the laminin β3-high group than for the laminin β3-low group (52.3 vs. 70.7%, P = 0.038), while there was no significant difference among Stage II patients. Among laminin β3-low Stage III patients, those who received adjuvant chemotherapy showed marginally better disease-free survival than those who did not receive it (75.8 vs. 62.8%; P = 0.096). Furthermore, multivariate analysis corroborated a distinct benefit of adjuvant chemotherapy in laminin β3-low patients (P = 0.035; hazard risk ratio = 1.66). Analyses of the laminin β3-high group, however, failed to show significance.

CONCLUSIONS

Laminin β3 chain immunoreactivity was a poor prognostic factor for Stage III colorectal cancer patients, and laminin β3-high patients of Stage III colorectal cancer derived no survival benefit from adjuvant chemotherapy.

Immunohistochemical alterations in invasive adenocarcinoma in endoscopically resected adenoma and factors associated with risk of residual or recurrent disease

AIM

We determined the pattern of immunohistochemical expression in invasive adenocarcinoma in endoscopically resected adenoma, its relationship with the risk of residual or recurrent disease and the related factors.

METHOD

We included individuals with malignant polyps resected endoscopically in the period 1999-2009. Clinical and endoscopic data were collected. All histological specimens were re-analysed. CD44, matrix metalloproteinase 9 (MMP-9), vascular endothelial growth factor-β (VEGF-β), β-catenin, laminin and cyclooxygenase 2 (COX-2) expression were determined by immunohistochemistry. A multivariate logistic regression was performed to determine variables independently associated with the risk of residual or recurrent disease.

RESULTS

One-hundred and fifty-one malignant polyps (114 pedunculated; mean size ± SD=22.61 ± 10.86 mm) were resected endoscopically. Resection was fragmented and incomplete in 26.5% and 8.6% of patients, respectively. Surgical resection was performed on 71 (47%) patients. After a median follow-up of 44 months, residual (n=12) or recurrent (n=6) disease was detected in 17 patients. Conventional histology showed that 32.1% met high-risk histological criteria. Immunohistochemical expression was positive for CD44, MMP-9, VEGF-β, β-catenin, laminin and COX-2 in 63.3%, 25.3%, 45%, 38.8%, 79% and 34.5% of specimens, respectively, with no differences between both groups. Variables associated with residual or recurrent disease in the univariate analysis were: nonpedunculated morphology (P=0.07); fragmented (P<0.001) or incomplete resection (P<0.001); margin infiltration (P=0.04); and histological high-risk lesion (P=0.003). Finally, incomplete resection (OR=12.16, 95% CI=3.15-46.98; P<0.001) and histological high risk (OR=4.73, 95% CI=1.33-16.74; P=0.002) were independently associated with the risk of residual or recurrent disease.

CONCLUSION

Immunohistochemistry could not predict residual or recurrent disease. Only incomplete excision and histological high risk did so. The factors independently associated were histological high-risk lesion and incomplete resection.

C4.4A is associated with tumor budding and epithelial-mesenchymal transition of colorectal cancer

C4.4A is a glycolipid-anchored membrane protein expressed in several human malignancies. The aim of this study was to explore the association between C4.4A expression at the invasion front of colorectal cancer (CRC) and tumor budding, a putative hallmark of cell invasion of CRC. Advanced CRCs (T2-4, n = 126) had a budding count of 3.66 ± 5.66, which was significantly higher than that of T1 early CRCs (1.75 ± 2.78, n = 87). C4.4A-positive CRC specimens showed a larger budding cell number than C4.4A-negative CRC specimens in T1 CRCs, and especially advanced CRCs (9.45 ± 5.83 vs 1.60 ± 3.93). Furthermore, we found a correlation between the percentage of C4.4A-positive cases and budding count in advanced CRC. Multivariate analysis for patients' survival showed that C4.4A was superior to tumor budding as a prognostic factor. With siRNA treatment, C4.4A levels were associated with cell invasion, but not with proliferation, in HCT116 and DLD1 cell lines. An immunohistochemical study in a subset of CRCs showed no relationship between C4.4A and Ki-67 proliferation marker. In vitro assays using HCT116 indicated that C4.4A levels correlated well with epithelial-mesenchymal transition (EMT) with regard to cell morphology and alterations of EMT markers including E-cadherin, vimentin, and partially N-cadherin. We also found that C4.4A expression was significantly associated with loss of E-cadherin and gain of β-catenin in clinical CRC tissue samples. These findings suggest that a tight association between C4.4A and tumor budding may, in part, be due to C4.4A promoting EMT at the invasive front of CRC.

Epithelial-mesenchymal transition (EMT) protein expression in a cohort of stage II colorectal cancer patients with characterized tumor budding and mismatch repair protein status

INTRODUCTION

The relationship between tumor budding, epithelial-mesenchymal transition (EMT) protein expression, and survival has not been closely examined in stage II colorectal cancer (CRC). This study aimed to assess proteins implicated in EMT and to correlate their expression with tumor budding, microsatellite status, and survival.

METHODS

A total of 258 stage II CRCs were identified (tumor budding characterized in 122 cases). Immunohistochemistry for LAMC2, E cadherin, cathepsin L, and β catenin using tissue microarrays was performed. EMT and mismatch repair (MMR) protein expression were correlated with tumor budding and survival.

RESULTS

LAMC2 positivity (P < .001) and low membranous β catenin (P = .056) were associated with tumor budding. In a univariate survival analysis, tumor budding (P < .001), LAMC2 positivity (P < .03), and stromal cytoplasmic cathepsin L (P = .025) predicted poorer prognosis. Multivariate analysis showed tumor budding to be the only variable independently associated with survival: hazard ratio = 7.9 (95% confidence interval = 3-21); P < .001. Tumor budding was more frequent in microsatellite-stable (MSS) versus microsatellite-instable (MSI) tumors: 48% versus 26%, respectively; P = .087. MSS cases exhibited reduced membranous β catenin (P = .002) and increased cytoplasmic and nuclear β catenin (P < .001) compared with MSI cases.

CONCLUSION

Epithelial mesenchymal protein expression plays a key role in tumor budding and prognosis in early-stage colorectal cancer and requires further evaluation.

Epithelial mesenchymal transition and tumor budding in aggressive colorectal cancer: tumor budding as oncotarget

Epithelial mesenchymal transition (EMT) is proposed as a critical mechanism for the acquisition of malignant phenotypes by epithelial cells. In colorectal cancer, tumor cells having undergone EMT are histologically represented by the presence of tumor buds defined as single cells or small clusters of de-differentiated tumor cells at the invasive front. Tumor budding is not a static, histological feature rather it represents a snap-shot of a dynamic process undertaken by an aggressive tumor with the potential to disseminate and metastasize. Strong, consistent evidence shows that tumor budding is a predictor of lymph node metastasis, distant metastatic disease, local recurrence, worse overall and disease-free survival time and an independent prognostic factor. Moreover, the International Union against Cancer (UICC) recognizes tumor budding as a highly relevant, additional prognostic parameter. The aim of this review is to summarize the evidence supporting the implementation of tumor budding into diagnostic pathology and patient management and additionally to illustrate its worthiness as a potential therapeutic target.

Immunohistochemical evaluation of type IV collagen and laminin-332 γ2 chain expression in well-differentiated oral squamous cell carcinoma and oral verrucous carcinoma: a new recommended cut-off

BACKGROUND

Invasion and metastasis are two characteristics of malignant tumors, which perform by proteolytic destruction of the components of basement membrane (BM) and cell migration. The aim of this study was to evaluate the immunohistochemical (IHC) assessment of type IV collagen and laminin-332 γ2 (Ln-332 γ2) chain expression in well-differentiated oral squamous cell carcinoma (OSCC) and oral verrucous carcinoma (OVC), because these two lesions have same histopathologic findings whereas they have different biological behaviors.

METHODS

Destruction of BM and cell migration were evaluated by IHC in 15 cases of epithelial hyperplasia with no dysplasia (A group), 15 cases of OVC (B group) and 15 cases of well-differentiated OSCC (C group).

RESULTS

There was a significant difference in type IV collagen immunohistochemical staining between three groups, but there were no significant differences between B and C groups. Expression of Ln-332 γ2 chain was not detected in A group. Ln-332 γ2 chain labeling index had significantly difference between B and C groups. The number of Ln-332 γ2 chain immunostaining positive cells was less than 5% in B group and over than 5% in C group which there were significantly differences between these two groups.

CONCLUSIONS

Isolated immunohistochemical study of type IV collagen does not clearly define that a lesion is invasive or non-invasive and evaluation of Ln-332 γ2 chain expression (cut-off 5%) may be useful as a marker for description of biological differences and diagnosis of OVC from well-differentiated OSCC, especially in doubtful cases.

ABCG5-positivity in tumor buds is an indicator of poor prognosis in node-negative colorectal cancer patients

AIM: To analyze the expression of 8 putative cancer stem cell (CSC) markers within colorectal cancer tumor buds and to determine their prognostic impact in patients with this disease.

METHODS: Immunohistochemistry was performed on 101 colorectal cancer resections for CK22 (to identify tumor buds) as well as CD133, CD166, CD24, CD44s, CD90, EpCAM, ALDH1, and ABCG5, and their expression within tumor buds was evaluated.

RESULTS: CD90, CD44s, and CD133 expression in tumor buds was found in less than 5% of all cases. ALDH1, CD24, CD166 were expressed in 16.5%, 16.2%, and 34% cases, respectively, while ABCG5 and EpCAM expression was more frequent and found in 35% and 69% of cases, respectively. Of the 8 markers studied, EpCAM and ABCG5 positivity in tumor buds were significantly associated with poor prognosis (P = 0.023, P = 0.038, respectively) in multivariable analysis with pT and pN classification [P = 0.048; hazard ratio (HR): 2.64; 95% CI: 1.0-6.9, for EpCAM and P = 0.029; HR: 2.22; 95% CI: 1.0-4.5, for ABCG5]. Poor survival time was particularly striking for lymph node-negative patients with ABCG5-positive buds (P < 0.001).

CONCLUSION: Expression of putative stem cell markers EpCAM and ABCG5 within the tumor buds of colorectal cancer are frequently noted and are associated with poor prognosis.

Defining the role of laminin-332 in carcinoma

The deadly feature of cancer, metastasis, requires invasion of cells through basement membranes (BM), which normally act as barriers between tissue compartments. In the case of many epithelially-derived cancers (carcinomas), laminin-332 (Ln-332) is a key component of the BM barrier. This review provides a historical examination of Ln-332 from its discovery through identification of its functions in BM and possible role in carcinomas. Current understanding points to distinct roles for the three Ln-332 subunits (alpha3, beta3, gamma2) in cell adhesion, extracellular matrix stability, and cell signaling processes in cancer. Given the large number of studies linking Ln-332 gamma2 subunit with cancer prognosis, particular attention is given to the crucial role of this subunit in cancer invasion and to the unanswered questions in this area.

Tumor budding as an index to identify high-risk patients with stage II colon cancer

PURPOSE

High-risk patients with Stage II colon cancer may benefit from adjuvant chemotherapy, but they are difficult to identify. We assessed the value of tumor budding, defined as small clusters of undifferentiated cancer cells at invasive margins, as a predictor of outcomes in patients with Stage II colon cancer.

METHODS

We studied a total of 200 patients with Stage II colon cancer who underwent curative surgery. With hematoxylin and eosin-stained specimens, the degree of tumor budding was classified as low-grade or high-grade. The survival rate of patients who had Stage II disease with low-grade or high-grade tumor budding was compared with that of 226 patients who had Stage III colon cancer.

RESULTS

Univariate analysis revealed that serosal surface involvement (P = 0.04) and tumor budding (P < 0.001) were significantly related to survival. Cumulative five- and ten-year survival rates differed significantly between patients with low-grade tumor budding (93.9 and 90.6 percent, respectively) and those with high-grade (73.9 and 67.8 percent, respectively). Survival rates did not differ significantly between patients with Stage II disease who had high-grade tumor budding and patients with Stage III disease. Cox's regression analysis demonstrated that tumor budding (hazard ratio, 4.89; P < 0.001) and serosal surface involvement (hazard ratio, 2.561; P = 0.023) were independent prognostic factors. Liver (P < 0.001) and peritoneal (P = 0.003) metastases were more frequent in the patients with high-grade tumor budding than in those with low-grade.

CONCLUSIONS

Tumor budding is useful for prognosis and identifying patients with Stage II colon cancer who have a high risk of disease recurrence after curative surgery.

Tumour budding at invasive margins and outcome in colorectal cancer

OBJECTIVE

Tumour budding, defined as small clusters of undifferentiated cancer cells at invasive margins, has been shown to reflect biologic aggressiveness of colorectal cancers. We therefore examined the prognostic significance of tumour budding in patients with colorectal carcinoma, particularly focusing on comparisons with other clinicopathological findings.

METHOD

Tumour budding was investigated in surgically resected specimens from 159 patients with colorectal carcinoma. With haematoxylin and eosin stained slides containing the entire invasive margin, the degree of tumour budding was classified into three grades: mild, <1/3 of the entire invasive margin; moderate, 1/3-2/3; marked, >2/3.

RESULTS

Mild tumour budding was found in 54 (34%) cases, moderate in 59 (37%) cases and marked in 46 (29%) cases. The degree of budding was linked with poor tumour differentiation, lymph node metastasis and advanced TNM stage (P < 0.001). In univariate analysis, patients with marked tumour budding [5-year cancer-related survival (CRS)/recurrence-free survival (RFS), 39%/53%] had significantly worse survival [CRS, hazard ratio (HR), 4.561; 95% confidence interval (CI), 2.265-9.184; P < 0.001; RFS, HR, 3.240; 95% CI, 1.430-7.342; P = 0.005] than those with mild (5-year CRS/RFS, 80%/82%) or moderate (63%/66%) budding. In the Cox regression model, marked tumour budding (HR, 3.137; 95% CI, 1.517-6.487; P = 0.002) and advanced tumour stage (stage III, HR, 3.226; 95% CI, 1.475-7.053; P = 0.003; stage IV, HR, 24.443; 95% CI, 10.843-55.100; P < 0.001) proved to be an independent predictor of short CRS.

CONCLUSION

Tumour budding is a practical and significant histological index for identification of high malignant potential and poor outcome in patients with colorectal carcinoma.

Intensity of tumor budding and its prognostic implications in invasive colon carcinoma

PURPOSE

The aim of this study was to assess the intensity of tumor budding in colon carcinoma quantitatively and to determine its correlation with malignancy potential.

METHODS

The intensities of tumor budding at the invasive front of surgical specimens from 174 patients with well-differentiated or moderately differentiated colon carcinoma were investigated. Differences in intensity among clinicopathologic parameters were compared, and recurrences and survivals were analyzed in accordance with degree of the intensity.

RESULTS

Tumor budding was identified in 155 patients (89 percent) and the mean intensity (+/- standard deviation) of budding was, on the whole, 6.6 +/- 5.6. Intensity was significantly higher in tumors with lymphatic and vascular invasion than in those without (9.1 +/- 6.6 vs. 4.8 +/- 3.9 and 9.8 +/- 6.1 vs. 5.4 +/- 4.9; P < 0.0001, respectively). It became significantly higher with increasing T and N stage (P = 0.0013 and < 0.0001, respectively). Both the Cox model and the linear logistic regression indicated that higher intensity was significantly associated with higher risk of postoperative recurrence (P = 0.017 and 0.0001, respectively). When patients were stratified into four groups based on the quartiles of the distribution of intensity, the group of higher quartiles showed significantly less favorable outcome in terms of both five-year disease-free (P = 0.0039) and overall survival (P = 0.0263). The cutoff of the intensity considered to be the best indicator for separating patients with regard to survival was third quartiles (intensity, 9). Based on multivariate analysis, the intensity of budding proved to be a significant covariate associated with disease-free survival (hazard ratio, 2.061; P = 0.0066).

CONCLUSIONS

The intensity of tumor budding at the invasive margin is suggested to be a significant pathologic index, indicating higher malignancy potential and the intensity greater than nine may be considered an adverse prognostic indicator in patients with colon carcinoma.

A novel classification of tumour budding in colorectal cancer based on the presence of cytoplasmic pseudo-fragments around budding foci

AIMS

Tumour budding is an adverse prognostic factor in colorectal cancer (CRC). We have investigated the significance of cytoplasmic fragments occurring in the immediate vicinity of tumour budding foci.

METHODS AND RESULTS

Seventy-three CRCs with high-grade budding (> 10 budding foci in a x 20 objective field) were classified according to extent of budding (10-19 versus 20+ foci) and by the presence or absence of cytoplasmic fragments identified by immunostaining for cytokeratin. In serial sections, cytoplasmic fragments were shown to be dendritic cell processes in continuity with budding tumour cells and were renamed pseudo-fragments. Cytoplasmic pseudo-fragments, but not extent of budding, were associated with aberrant expression of beta-catenin (P = 0.045) and laminin-5 gamma2 (P < 0.0001), and with absent peritumoral lymphocytic infiltration (P = 0.0077). Cytoplasmic pseudo-fragments had a stronger association with infiltrating growth pattern (P = 0.0014) than extent of tumour budding (P = 0.014). There was no association between extent of budding and cytoplasmic pseudo-fragments (P = 0.12).

CONCLUSIONS

Cytoplasmic pseudo-fragments may be a marker for an activated budding phenotype that is associated with cell motility and increased invasiveness in CRC and is independent of the extent of budding.

Intensity of tumor budding as an index for the malignant potential in invasive rectal carcinoma

PURPOSE

The aim of this study was to quantitatively assess the intensity of tumor budding in rectal carcinoma and to determine how it correlates with the malignant potential.

MATERIALS AND METHODS

Intensities of the tumor budding at the invasive front of the surgical specimens from 90 patients (male, 51) with well- or moderately-differentiated rectal carcinoma were investigated. Differences in the budding intensity among pathologic variables were compared, and recurrences and survivals were analyzed in accordance with degree of the budding intensity. The patients ranged in age from 33 to 75 years (mean, 55.4) with the median follow-up being 43 months (range, 12 approximately 108).

RESULTS

Tumor budding was identified in 89 patients (98.9%) with a mean intensity of 7.5+/-5.3. The budding intensity was significantly higher in tumors with lymphatic invasion (p=0.0081), blood vessel invasion (p<0.0001), and perineural invasion (p=0.0013) than in those tumor without these findings. It became significantly higher with the increase in nodal stage (p<0.0001). The intensity of tumor budding in patients with relapse (29 patients) was significantly higher than that in patients without relapse (6.2+/-5.0 vs. 10.2+/-4.9; p=0.0005), but this difference in the intensity was observed only for the node-positive patients (8.0+/-3.4 vs. 11.9+/-5.1; p=0.0064). When the patients were stratified into two groups on either side of the mean of the intensity, the higher intensity group showed a significantly less favorable disease-free (DFS) and overall survival (OS) (p=0.0026 and 0.0205, respectively). Based on the multivariate analysis, the nodal stage and the intensity of budding proved to be the independent variables associated with DFS (p=0.023 and 0.03, respectively).

CONCLUSION

Tumor budding at the invasive margin is a reliable pathologic index that indicates a higher malignant potential and a less favorable prognosis for patients with advanced rectal carcinoma.

Ly6 family member C4.4A binds laminins 1 and 5, associates with galectin-3 and supports cell migration

C4.4A is a member of the Ly6 family, with low homology to uPAR. It has been detected mainly on metastasizing carcinoma cells and proposed to be involved in wound healing. So far, C4.4A has been observed as an orphan receptor, and its functional activity has not been explored. Using recombinant rat C4.4A (rrC4.4A) made in a eukaryotic expression system, we demonstrate by immunohistology that C4.4A ligands are strongly expressed in tissues adjacent to squamous epithelia of, e.g., tongue and esophagus, the expression pattern partly overlapping with laminin (LN) and complementing the C4.4A expression that is found predominantly on the basal layers of squamous epithelium. ELISA screening of several components of the extracellular matrix revealed selective binding of rrC4.4A to LN1 and LN5 and that transfection of the BSp73AS tumor line with C4.4A cDNA (BSp73AS-1B1) promoted LN1 and LN5 binding. Binding of BSp73AS-1B1 to LN5 and, less markedly, LN1 induced spreading, lamellipodia formation and migration. C4.4A also associates with galectin-3 in nontransformed tissues and tumor lines. There is evidence that the association of C4.4A with galectin-3 influences LN adhesion. C4.4A was described originally as a metastasis-associated molecule. Our findings that LN1 and LN5 are C4.4A ligands, that galectin-3 associates with C4.4A and that C4.4A ligand binding confers a migratory phenotype are well in line with the supposed metastasis association.

Prognostic implication of laminin-5 gamma 2 chain expression in the invasive front of colorectal cancers, disclosed by area-specific four-point tissue microarrays

The laminin-5 gamma 2 chain (LN-5gamma2) is known to be a marker of invasion in several cancer types. Our purpose was to examine the prognostic significance of LN-5gamma2 expression in different areas of individual colorectal cancers (CRCs) by using tissue microarrays (TMAs), and to clarify the optimal areas for prognostic assessment. Using formalin-fixed paraffin-embedded tissue blocks of pT3 primary CRCs resected from 120 patients, we constructed TMA blocks of tissue core specimens taken from the submucosal invasive front, subserosal invasive front, central area, and rolled edge of each tumor. Using these four-point TMA sets, cytoplasmic LN-5gamma2 expression was immunohistochemically surveyed, and the area-specific prognostic significance of LN-5gamma2 expression was evaluated. The data revealed that 35, 30, 15 and 10% of the 120 CRCs showed high-grade LN-5gamma2 expression in the submucosal invasive front, subserosal invasive front, central area and rolled edge, respectively. Disease-specific survival curves for the groups with high- and low-grade LN-5gamma2 in the submucosal invasive front and subserosal invasive front were different significantly or of marginal difference (respective 5-year survival rates: 54 and 78% for submucosal invasive front (P=0.030) and 58 and 75% for subserosal invasive front (P=0.055)). Multivariate analysis revealed that the grades of LN-5gamma2 expression in submucosal invasive front (hazard ratio=2.0, P=0.047) and subserosal invasive front (hazard ratio=2.9, P=0.0033) were independent prognostic factors. In contrast, the grades of LN-5gamma2 expression in the central area and rolled edge did not have a significant impact on patient prognosis. Analysis using area-specific four-point TMAs clearly demonstrated that LN-5gamma2 expression in the invasive front largely influences the degree of clinical aggressiveness of CRC and its tendency to metastasize.

Recent progress in predictive biomarkers for metastatic recurrence of human hepatocellular carcinoma: a review of the literature

Molecular markers (biomarkers) for hepatocellular carcinoma (HCC) metastasis and recurrence could provide additional information to that gained from traditional histopathological features. A large number of biomarkers have been shown to have potential predictive significance. One important aspect of this is to detect the transcripts of tumor-associated antigens (such as AFP, MAGEs, and CK19), which are proposed as predictive markers of HCC cells disseminated into the circulation and for metastatic recurrence. Another important aspect is to analyze the molecular markers for cellular malignancy phenotype, including DNA ploidy, cellular proliferation index, cell cycle regulators, oncogenes, and tumor suppressors (especially p53 gene), as well as telomerase activity. Molecular factors involved in the process of HCC invasion and metastasis, including adhesion molecules (E-cadherin, catenins, ICAM-1, laminin-5, CD44 variants, osteopontin), proteinases responsible for the degradation of extracellular matrix (MMPs, uPA system), as well as angiogenesis regulators (such as VEGF, intratumor MVD), have also been shown to be potential predictors for HCC metastatic recurrence and clinical outcomes. One important new trend is to widely delineate biomarkers with genomic and proteomic expression with reference to predicting metastatic recurrence, molecular diagnosis, and classification, which has been drawing more attention recently. Body fluid (particularly blood and urine) testing for biomarkers is easily accessible and more useful in clinical patients. The prognostic significance of circulating DNA in plasma or serum and its genetic alterations is another important direction. More attention should be paid to these areas in the future. As understanding of tumor biology deepens, more and more new biomarkers with high sensitivity and specificity for HCC metastatic recurrence could be found and routinely used in clinical assays. However, the combination of the pathological features and some of the biomarkers mentioned above seems to be more practical up to now.