Apoptosis as an independent prognostic indicator in squamous cell carcinoma of the esophagus

Clinical significance of the expression of connexin26 in colorectal cancer

Background

Connexin26 (Cx26) is one of the connexins (Cxs) family members which form gap junction channels. Cx26 is considered to be a tumor suppressor gene. However, recent studies revealed that over expression of Cx26 is associated with a poor prognosis in several human cancers. This study investigated the correlation between Cx26 expression and the clinicopathological features and P53 expression in colorectal cancer.

Methods

One hundred and fifty-three patients who underwent a curative resection were studied. Tissue samples were investigated by immunohistochemical staining using antibodies for Cx26 and P53. Moreover, apoptotic cells were detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling (TUNEL) staining.

Results

Cx26 expression was found in 83 cases (54.2%) and P53 expression in 71 cases (46.4%). A correlation was observed between the Cx26 expression and recurrence, histology, and p53 expression (P < 0.05). Cx26 positive tumors had significantly longer survival than Cx26 negative tumors (P < 0.05). A multivariate Cox analysis demonstrated that Cx26 expression was an independent prognostic factor (P < 0.05). However, no significant correlation was observed between Cx26 and AI.

Conclusion

This study suggests that Cx26 expression is an independent prognostic factor in patients that undergo a curative resection of colorectal cancer.

Response to chemoradiatiotherapy in squamous cell carcinoma of the esophagus: evaluation of some prognostic factors

Objective:

To evaluate the predictive values of the expression of factor VIII, CD-34, p53, bcl-2, and DNA ploidy regarding the response to chemoradiation of squamous cell carcinoma of the esophagus.

Design:

Retrospective analysis of pretreatment biopsies with immunohistochemistry and flow cytometry. The results were correlated to tumor response (complete vs. noncomplete) following chemoradiation with three cycles of 5-FU and cisplatin combined with 40–64 Gy of radiation.

Subjects:

44 consecutive patients with squamous cell carcinoma of the esophagus treated with chemoradiation with a curative intent from 1992–2000.

Main outcome measures:

Treatment response.

Results:

No correlations were found between the expressions of p53, bcl-2, or DNA ploidy and tumor response to chemoradiation. A positive correlation was found between factor VIII expression and a complete tumor response (p = 0.0357). However the other marker for angiogenesis, CD-34, showed a negative correlation (p = 0.0493). Both markers indicate blood vessel density meaning that, in this study, many vessels indicated a favorable response if measured with factor VIII, but a poor response if measured with CD-34.

Conclusion:

It is not possible to predict tumor response to our chemoradiation protocol through the analysis of pretreatment expression of p53, bcl-2 or DNA ploidy in biopsy specimens. In spite of significant correlations between complete tumor responses and the expressions of the markers for angiogenesis this significance may be questionable since one of the two markers, factor VIII had a positive and the other,CD-34, a negative correlation to tumor response.

Increased E2F-1 expression via tumour cell proliferation and decreased apoptosis are correlated with adverse prognosis in patients with squamous cell carcinoma of the oesophagus

BACKGROUND

The retinoblastoma (Rb) pathway, which governs cell cycle progression, is frequently genetically altered in cancer, causing deregulated expression of the E2F-1 transcription factor, which promotes DNA synthesis and cell cycle progression. Recent studies show that E2F-1 also participates in apoptosis induction in a p53 dependent or independent manner. Despite its crucial role and paradoxical effects on cell turnover, the function of E2F-1 in human cancer is unclear.

AIMS

To evaluate E2F-1 expression using immunohistochemistry in 43 surgically resected oesophageal squamous cell carcinoma (OSCC) specimens.

METHODS

This study analysed the association of E2F-1 with tumour cell proliferation and apoptosis and the upstream regulators modulating these processes, and its impact on patient outcome. Tumour cell proliferation and apoptosis were assessed as percentage of MIB-1 positive or apoptotic cells (MIB-1 labelling index (MI) and apoptotic index (AI)), respectively.

RESULTS

Entire specimens showed abnormal expression of one or more upstream regulators of pRb/E2F-1. Although E2F-1 positivity was not associated with the expression of upstream regulators, it showed a linear and positive correlation with MI but not AI. Patients with high MI, low AI, or high E2F-1 positivity had significantly shorter recurrence free survival. By multivariate analysis, high MI and low AI were independently associated with recurrence free survival, but E2F-1 was not.

CONCLUSIONS

Increased cell proliferation and decreased apoptosis are associated with adverse prognosis in patients with OSCC. Although E2F-1 remains a controversial prognostic factor, its expression was closely associated with tumour cell proliferation and might influence clinical outcome, mainly via cell cycle progression.

Differential protein expression between esophageal squamous cell carcinoma and dysplasia, and prognostic significance of protein markers

The aim of the current study was to evaluate the protein expression involved in the progression from dysplasia to invasive esophageal squamous cell carcinomas and to analyze the prognostic value of markers. Immunohistochemistry was performed for cell cycle regulators [p53, p21, p27, p16, cyclin D1, Rb], apoptosis-related proteins [Fas, Fas-L, FADD, TRAIL, DR4, DR5, caspase-8, caspase-3, bcl-2, Bax], tumor suppressor proteins [beta-catenin, E-cadherin, FHIT, Smad 4, VHL, PTEN, KAI-1], and oncoproteins [c-myc, COX-2, EGFR]. Caspase-3, TRAIL, Fas-L, Fas, Smad 4, VHL, E-cadherin, and EGFR revealed significant differences between dysplasia and their corresponding invasive cancer portion in 25 cases. In a total of 118 cases of invasive cancer, proteins with frequent (> or = 60% of the cases) alterations were p53 (overexpression in 64% of SCCs), p27 (loss in 91%), p16 (loss in 81%), and FHIT (loss in 75%). Early clinical stage and bcl-2 immunopositivity were related to the survival rate of patients. In conclusion, caspase-3, TRAIL, Fas-L, Fas, Smad 4, VHL, E-cadherin, and EGFR may be involved in the progression from dysplasia to invasive esophageal SCCs. Clinical stage and bcl-2 are independent prognostic factors throughout the multivariate analysis.

Serum nucleosomes during neoadjuvant chemotherapy in patients with cervical cancer. Predictive and prognostic significance

Background

It has been shown that free DNA circulates in serum plasma of patients with cancer and that at least part is present in the form of oligo- and monucleosomes, a marker of cell death. Preliminary data has shown a good correlation between decrease of nucleosomes with response and prognosis. Here, we performed pre- and post-chemotherapy determinations of serum nucleosomes with an enzyme-linked immunosorbent assay (ELISA) method in a group of patients with cervical cancer receiving neoadjuvant chemotherapy.

Methods

From December 2000 to June 2001, 41 patients with cervical cancer staged as FIGO stages IB2-IIIB received three 21-day courses of carboplatin and paclitaxel, both administered at day 1; then, patients underwent radical hysterectomy. Nucleosomes were measured the day before (baseline), at day seven of the first course and day seven of the third course of chemotherapy. Values of nucleosomes were analyzed with regard to pathologic response and to time to progression-free and overall survival.

Results

All patients completed chemotherapy, were evaluable for pathologic response, and had nucleosome levels determined. At a mean follow-up of 23 months (range, 7–26 months), projected progression time and overall survival were 80.3 and 80.4%, respectively. Mean differential values of nucleosomes were lower in the third course as compared with the first course (p >0.001). The decrease in the third course correlated with pathologic response (p = 0.041). Survival analysis showed a statistically significant, better progression-free and survival time in patients who showed lower levels at the third course (p = 0.0243 and p = 0.0260, respectively). Cox regression analysis demonstrated that nucleosome increase in the third course increased risk of death to 6.86 (95% confidence interval [CI 95%], 0.84–56.0).

Conclusion

Serum nucleosomes may have a predictive role for response and prognostic significance in patients with cervical cancer patients treated with neoadjuvant chemotherapy.

Expression of heat-shock protein Hsp60 correlated with the apoptotic index and patient prognosis in human oesophageal squamous cell carcinoma

Cellular stress response and apoptosis are two highly conserved mechanisms for maintaining homeostasis. Hsp60 and Hsp90 have been shown to play pro- and anti-apoptotic roles, respectively. Our present study examined whether there is a correlation between the expression of Hsp60 and Hsp90, clinical parameters, the apoptotic index (AI), and the prognosis of patients with oesophageal squamous cell carcinoma (ESCC). We immunohistochemically stained cells for Hsp60, Hsp90, and single-stranded DNA (ssDNA), which acts as an apoptotic marker. In normal oesophageal epithelium tissue, Hsp60 and Hsp90 were expressed in the cytoplasm and membrane from the basal cell layer to the supra-basal cell layers. Hsp60 and Hsp90 positive stainings (+) were found in 63 of 123 cases (51%) and 62 of 123 cases (50%), respectively. There was no correlation between Hsp60 and Hsp90 expression levels and any of the clinical parameters examined. The five-year survival rate for ESCC patients with Hsp60 (+) expression was significantly higher than for those patients with Hsp60 (-) expression (P=0.0371). Five-year survival rates of patients with Hsp60 (+) and (-) were 49% and 33%, respectively. By contrast, Hsp90 expression failed to predict patient prognosis (P=0.7965). The high-AI group did not have a significantly better prognosis than the low-AI group (P=0.2218). Statistical analysis showed a significant correlation between the expression of Hsp60 and AI in ESCC patients (P=0.008). Thus, the five-year survival rate for the high-AI/Hsp60 (+) group was statistically significantly better than for the other groups (P=0.0281). The results obtained in this study indicate that positive Hsp60 expression is a good prognostic indicator. This may be due to its role as a chaperone in contributing to the induction of apoptosis. These data suggest that Hsp60 expression correlates with the AI and patient prognosis in human ESCC.

Impact of frequent Bcl-2 expression on better prognosis in renal cell carcinoma patients

Previously, we reported that Bcl-2 was frequently expressed in renal cell carcinoma (RCC) specimens, but p53 mutation was a rare event. However, it was unclear whether Bcl-2 positivity was associated with the clinicopathological characteristics and prognosis in RCC. Therefore, we investigated the expression of Bcl-2 protein and its roles in 101 RCC specimens. In addition, the proliferation index (PI), apoptotic index (AI), caspase-3 and p53 expression were examined. The immunohistochemical method was applied for Bcl-2, caspase-3 and p53 protein expression. To investigate the proliferation activity and apoptosis of tumour cells, PI and AI were calculated based on Ki-67 and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labelling (TUNEL)-positive cells, respectively. Bcl-2 expression was detected in 72 out of 101 (71.3%) specimens. Bcl-2 positivity was inversely correlated with PI (P<0.0001) and AI (P=0.0074). Furthermore, Bcl-2 positivity was significantly correlated with better survival (P=0.0014), and was associated with lower stage (P=0.0301) and grade (P=0.0020). In RCC, frequent Bcl-2 expression was correlated with favourable character without higher PI and AI. Thus, Bcl-2 expression might be applied as a novel predictor of better prognosis in RCC patients.