Prognostic significance of heat shock proteins 27 and 70 in patients with squamous cell carcinoma of the esophagus

Heme oxygenase-1 expression predicts cervical lymph node metastasis of tongue squamous cell carcinomas

Heme oxygenase-1 (HO-1) is known as a stress-inducible protein. The present study was designed to investigate the relationship between HO-1 expression levels and clinical features of tongue cancer by using HO-1 responsiveness to stress as a clinical indicator. One-hundred and twelve biopsy samples from tongue squamous cell carcinomas were analyzed semiquantitatively by immunohistochemistry. Correlations between the expression level of HO-1 and the clinical features of tumors were statistically analyzed. Fifty-four cases with surgical confirmation of lymph node metastasis were examined for the association between cervical lymph node metastasis (pN) and other clinical features, including the HO-1 expression level, using logistic regression. The low HO-1 expression group contained significantly more undifferentiated samples (P=0.04) and pN positive cases (P=0.01) by univariate analysis. The low HO-1 expression group (odds ratio=8.49; 95% confidence interval=1.64-44.09, P=0.01) and an endophytic shape (odds ratio=16.79; 95% confidence interval=1.77-159.53, P=0.01) were significantly associated with an increased risk of developing lymph node metastasis by multivariate analysis. Low HO-1 expression was associated with lymph node metastasis. The expression profile suggests HO-1 could be used clinically as a marker for tumors possessing the potential for lymph node metastasis. This method could prove useful as an adjuvant method to detect lymph node metastasis and may help reduce the number of surgeries by indicating when surgery is unnecessary.

Nuclear BAG-1 expression is a biomarker of poor prognosis in esophageal squamous cell carcinoma

Apoptosis is one of the critical biological factors that correlate with the biological behavior of malignant tumors including cancer progression and clinical outcome. The present study was performed to clarify the clinical implications of BAG-1, a bcl-2 binding protein in esophageal squamous cell carcinoma (ESCC). Seventy-one cases with ESCC were investigated. Immunohistochemical study of BAG-1 was performed on resected specimens. The expression pattern of BAG-1 in nuclei and/or cytoplasm was analyzed and correlated with TNM classification, vessel invasion, survival period after surgery. BAG-1 expression in the nuclei was related to the depth of tumor invasion (P = 0.0381) but not to any other clinicopathologic parameters. The cytoplasmic staining pattern of BAG-1 exhibited no correlation with clinicopathologic parameters. Univariate analysis (P < 0.05), but not multivariate analysis, revealed significantly poor prognosis for ESCC cases exhibiting positive nucleic staining for BAG-1. Our data suggests that BAG-1 expression in the nuclei of ESCC plays an important role in tumor development and may be useful for predicting the prognosis after surgery.

Heat shock proteins HSP27, HSP60, HSP70, and HSP90: expression in bladder carcinoma

BACKGROUND

Heat shock proteins (HSPs) are synthesized by cells in response to various stress conditions, including carcinogenesis. The expression of HSPs in neoplasia has been implicated in the regulation of apoptosis, and HSPs also can act by increasing immunity. In the current study, the authors attempted to clarify the significance of HSPs in bladder carcinoma and their effect on tumor behavior.

METHODS

Expression levels of the 27-kilodalton HSP (HSP27), HSP60, HSP70, and HSP90 were studied using immunohistochemistry on tissue sections from 42 transitional cell carcinomas of the bladder (14 Grade 1 tumors; 13 Grade 2 tumors; 15 Grade 3 tumors, including 3 tumors associated with carcinoma in situ; 30 Stage Ta tumors; 7 Stage T1 tumors; and 5 Stage T2 tumors). Bladder specimens from 10 healthy patients were used as controls in the study. The selected patients had a mean follow-up of 52 months (range, 24-78 months). Among the 37 patients with superficial bladder carcinoma, 17 patients did not have any recurrence after undergoing primary resection, and 20 patients developed recurrent disease, including 4 recurrences with muscle invasion. HSP expression was evaluated according to the percentage of positively stained cells, and loss of expression was defined as < 80% of stained cells.

RESULTS

In normal bladder specimens, all four HSPs (HSP27, HSP60, HSP70, and HSP90) were expressed strongly in the cytoplasm and membrane from the basal cell layer to the superficial cell layer. Loss of expression was detected in tumors: respectively, 45.2%, 38.1%, 69.0% and 23.8% of tumors showed a loss of immunostaining for HSP27, HSP60, HSP70, and HSP90. No correlation between HSP expression and grade was found. Low expression levels of HSP27 and HSP60 were correlated with higher tumor stage (87% vs. 6% [P < 0.001] and 78% vs. 9% [P < 0.01], respectively). HSP60 and HSP90 expression levels were correlated with final outcome for patients with superficial bladder carcinoma: loss of expression was associated with the risk of developing an infiltrating recurrence (97% vs. 6.0% [P < 0.001] and 88.2% vs. 52.5% [P = 0.02] for HSP60 and HSP90, respectively).

CONCLUSIONS

HSPs were expressed in normal urothelium, and the current results indicated that loss of HSP60 and HSP90 expression may have prognostic relevance in patients with bladder carcinoma. The authors believe that HSP60 may be a very useful marker for patients with superficial bladder carcinoma and may be used for predicting disease progression. If these data are confirmed, low HSP60 expression levels may be usable as a prognostic marker to identify patients for whom local treatment would be insufficient.

Pharmacogenomics in cancer drug discovery and development: inhibitors of the Hsp90 molecular chaperone

Drug discovery is being revolutionised by a number of technological developments. These include high throughput screening, combinatorial chemistry and genomics. The impact of the new technologies is to accelerate the pace of anticancer discovery. The completion of the Human Genome Project and the ongoing high throughput sequencing of cancer genomes will facilitate the identification of a range of new molecular targets for drug discovery. Over the next few years we will have a complete molecular understanding of the various combinations of genes and cognate pathways that drive the malignant phenotype and tumour progression. The vision for postgenomic cancer drug discovery must be to identify therapeutic agents that correct or exploit each of these molecular abnormalities. In this way, it will be possible to develop personalised drug combinations that are targeted to the molecular make up of individual tumours. It is anticipated that these therapies will be more effective and less toxic than current approaches, although combinations of novel agents with existing cytotoxic therapies are likely to continue for some time. Examples of postgenomic, mechanism-based drugs include Glivec, Herceptin and Iressa, with many more agents undergoing preclinical and clinical development. An interesting new approach involves the development of inhibitors of heat shock protein (Hsp90) molecular chaperone. Because Hsp90 is required for the correct folding, stability and function of a range of oncoproteins that are mutated or over expressed in cancer, Hsp90 inhibitors have the potential to provide a simultaneous, combinatorial attack on multiple oncogenic pathways. By depleting the levels of multiple oncoproteins in cancer cells and blocking a wide range of oncogenic pathways, Hsp90 inhibitors have the potential to inhibit all of the hallmark characteristics of cancer cells. Progress in the preclinical and clinical development of Hsp90 inhibitors will be described, including an update on clinical studies with the first-in-class agent 17AAG. The use of the postgenomic technology of gene expression microarrays in cancer pharmacology and drug development will be exemplified.

Expression profiling in multistage hepatocarcinogenesis: identification of HSP70 as a molecular marker of early hepatocellular carcinoma

Hepatocellular carcinoma (HCC) associated with chronic liver disease evolves from precancerous lesions and early HCC to a progressed form. Nodule-in-nodule-type HCC (progressed HCC within early HCC) represents the transition from early to progressed HCC and, therefore, is useful in molecular genetic analysis of HCC progression during multistage carcinogenesis. We compared expression profiles among 7 early components and 7 progressed components of nodule-in-nodule-type HCCs and their corresponding noncancerous liver tissues with oligonucleotide array. Of the approximately 12,600 genes that were analyzed, a set of 95 genes provided a molecular signature that distinguished between early HCC components and their noncancerous liver tissues, and a set of 92 genes distinguished between progressed and early HCC components. Of these genes, the most abundantly up-regulated gene in early HCC components (P <.001) was heat-shock protein 70 (HSP70). Real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) confirmed this finding. Further immunohistochemical examination of HSP70 revealed its significant overexpression in early HCC compared with precancerous lesions (P <.001) and in progressed HCC compared with early HCC (P <.001). In conclusion, molecular signatures were clearly different in noncancerous liver tissue as compared with the early and progressed components of nodule-in-nodule-type HCC. Moreover, HSP70 could be a sensitive marker for the differential diagnosis of early HCC from precancerous lesion or noncancerous liver, a difficult distinction for pathologists due to very well differentiated histology with little atypia in early HCC.

Heat shock proteins: their role in urological tumors

PURPOSE

Heat shock proteins are ubiquitous molecules that are expressed in response to stress in all living organisms. The 3 important roles in regard to cancer development that have also been described are the regulation of apoptosis, modulation of the immune response and drug resistance.

MATERIALS AND METHODS

Recent studies have dramatically increased our current knowledge and understanding of the role of heat shock protein in cancer. We used a MEDLINE approach to examine the past and current literature.

RESULTS

The roles of heat shock protein in relation to urological tumors, namely those of the prostate, bladder, kidney and testis, are diverse. There are possible sites for heat shock protein modifications that may lead to new therapeutic approaches to urological cancer.

CONCLUSIONS

The possibility of treating patients with vaccines earlier in the disease course may stimulate research.

Immunohistochemical detection of pS2 protein and heat shock protein-70 in pancreatic adenocarcinomas. Relationship with disease extent and patient survival

We investigated pS2 and HSP-70 protein expression in 36 pancreatic adenocarcinomas for their effect on disease extent and patient outcome. The cases were reviewed, histologically diagnosed, typed, graded, and staged. Lymphatic vessel, blood vessel and perineural invasion as well as lymph node, resection margin and adjacent organ involvements were re-evaluated. The standard streptavidin biotin immunperoxidase method was used for immunostaining with pS2 and HSP-70 antibodies. Cytoplasmic staining with both antibodies was scored semiquantitatively. The scores were compared with histopathological prognostic parameters using statistical methods. Standard prognostic parameters and staining scores were tested by survival analysis in terms of their effect on survival. All the tumors showed a positive cytoplasmic reaction with HSP-70 antibody. Seventy-seven percent of the tumors showed positive cytoplasmic staining with pS2 antibody (22.2% +, 13.9% ++ and 41.7% +++). There was a statistically significant difference between HSP-70 staining scores with N status and final stages of the tumors (Chi-square, p = 0.03 and p = 0.026, respectively), while neither direct nor inverse correlation was detected for both parameters. PS2 staining scores showed no statistically significant relationship with tumor grade T, M status, perineural invasion, lymph and blood vessel invasion. In tumors with extensive staining with pS2, tumor stage tended to be low (Chi square, p = 0.024, Kendall Tau-b, r: -0.336, p = 0.036). There was a statistically significant difference and inverse correlation between tumors with extensive pS2 staining and tumors with less intense staining in terms of lymph node metastasis (Chi-square, p = 0.041, Kendall Tau: p = 0.024, r = -0,373). In the R0 resection group, in univariate analysis, we found that with higher scores of HSP-70 staining, the prognosis of the patient tended to improve. (Cox regression, p = 0.013). In multivariate analysis, HSP-70 expression was found to be an independent prognostic factor. We found no relationship between pS2 staining and patient survival.

Expression of heat shock protein 70 in grossly resected esophageal squamous cell carcinoma

BACKGROUND

The aim of the present study was to use immunohistochemical methods to clarify the clinical implication of heat shock protein (HSP) 70 expression in esophageal squamous cell carcinoma and to investigate the function of HSP70 as a chaperone for p53.

METHODS

Seventy-one patients with esophageal squamous cell carcinoma were admitted in the present study. Expression of HSP70 was analyzed by immunohistochemistry and correlated with TNM classification, vessel invasion, p53 expression, and clinical outcome after operation.

RESULTS

Overexpression of HSP70 was related to sex (p < 0.05), tumor configuration (p < 0.05), lymph node metastasis (p < 0.01), and lymphatic vessel invasion (p < 0.05). Expression of p53 and HSP70 were not correlated with each other (p = 0.824). Esophageal squamous cell carcinoma with HSP70 expression exhibited a significantly better prognosis compared with HSP70-negative esophageal squamous cell carcinoma in univariate analysis (p < 0.05), but no significance was found in multivariate analysis.

CONCLUSIONS

We suggest that HSP70 expression might be of use to assess the progression, lymph node metastasis, and lymphatic vessel invasion of esophageal squamous cell carcinoma. Inasmuch as both lymph node metastasis and HSP70 expression are prognostic variables in esophageal squamous cell carcinoma, examination of HSP70 expression may be of use to assess clinical outcome after operation.

The increase in the frequency of MICA gene A6 allele in oral squamous cell carcinoma

BACKGROUND

Oral squamous cell carcinoma (OSCC) was reported to be associated with immune function. The MICA (MHC class I chain-related gene A) is expressed by keratinocytes and other epithelial cells, and its encoded protein interacts with gamma/delta T cells localized in submucosa. The MICA also influences the heat shock protein function. We speculated that the alterations of MICA might influence the pathogenesis of OSCC through the aberration in presenting tumor antigens or heat shock protein. MICA gene has a triplet repeat (GCT) polymorphism in the transmembrane domain, resulting in five distinctive allelic patterns.

METHODS

We analysed this MICA polymorphism in 67 OSCC patients and 351 randomly selected unrelated controls. By using the ABI Prism 377-18 DNA sequencer (Applied Biosystems, Foster City, CA, USA) to analyse the sample DNA PCR products. The number of micro-satellite repeats was estimated with Genescan 672 software (Applied Biosystems) with a standard size marker of GS-350 TAMRA (N,N,N,N-tetramethyl-6-carbohydroxyl rhodamine; Applied Biosystems).

RESULTS

The phenotype frequency of allele A6 of MICA in subjects with OSCC was significantly higher than that in controls (RR = 3.46, 95% CI = 1.73-6.94, P = 0.0002), as was the frequency of allele (RR = 2.64, 95% CI = 1.39-5.02, P = 0.002).

CONCLUSION

The results suggest that allele A6 in MICA might confer the risk of OSCC.

p53-dependent regulation of heat shock protein 72

BACKGROUND

p53 is a key regulator of the cellular stress response. p53 modulates the transcription of several genes.

OBJECTIVES

To examine the influence of p53 on expression of heat shock protein 72 (HSP72).

METHODS

Two model systems were used. (i) HSP72 expression was studied by Western blot on extracts from p53-proficient or p53-deficient primary mouse keratinocytes, and (ii) archival human anogenital skin from fibroepithelial polyps, human papillomavirus (HPV) 16/18-associated lesions or squamous cell carcinomas (SCCs) was subjected to immunostaining for HSP72.

RESULTS

Basal HSP72 expression was higher in keratinocytes from p53-deficient than from p53-proficient mice. Immunostaining for HSP72 was higher in HPV 16/18 lesions and SCCs, which have reduced p53 protein.

CONCLUSIONS

p53 status may influence the basal level of HSP72.

Significant correlation between expression of heat shock proteins 27, 70 and lymphocyte infiltration in esophageal squamous cell carcinoma

The objective of this study was to clarify the clinicopathologic and prognostic significance of heat shock proteins (HSP) 27 and 70 expression in esophageal squamous cell carcinoma (SCC). Immunohistochemical staining for HSPs 27 and 70 was performed on surgical specimens obtained from 62 patients with esophageal SCC. The expression of both HSPs 27 and 70 correlated inversely with depth of invasion (P<0.05) and pathologic stage (P<0.05), and correlated positively with lymphocyte infiltration (P<0.05). Reduction of HSP 70 expression was significantly correlated with poor prognosis (P<0.05). Patients with HSP 27-negative tumors tended to have a poor prognosis compared with patients with HSP 27-positive tumors. The present findings suggest that HSPs 27 and 70 are significant prognostic factors for esophageal SCC.

General features of gastric carcinomas and comparison of HSP70 and NK cell immunoreactivity with prognostic factors

During the period of 1996-1998 ninety-four gastrectomy specimens with gastric carcinoma referred to Erciyes University, Medical Faculty, Department of Pathology, were examined histopathologically, histochemically and immunohistochemically. General characteristics of gastric carcinomas and prognostic factors were studied. According the Lauren classification, of the 94 cases of gastric carcinomas, 56 were intestinal type, 21 were diffuse type and 17 were mixed type carcinoma. The association rates of Helicobacter pylori, chronic atrophic gastritis and intestinal metaplasia with gastric carcinomas were high. There was strong immunorectivity with HSP70 in 62,5% of the intestinal type carcinomas. This ratios were lower in diffuse and mixed type carcinomas (p<0.05). The more tumor size and invasion depth increased, the more HSP70 immunoreactivity was obtained (p<0.05). HSP70 immunorectivity was considerably higher in the patients having lymph node metastasis and vascular invasion (p<0.05). It was found that the NK cell number was low in the tumor but higher around the tumor in early gastric carcinomas, compared with advanced carcinomas (p>0.05). In the tumors larger than 10 cm with vascular invasion, NK cell number was lower around the tumor (p>0.05). Defining prognostic factors of gastric carcinomas is of importance to clinicians. It is thought that HSP70 immunoreactivity, besides invasion depth, lymph node metastasis, vascular invasion, tumor size and inflammatory reaction against the tumor, is important in prognosis and associated with advanced stage.

Cell biology of laryngeal epithelial defenses in health and disease: preliminary studies

Esophageal epithelium has intrinsic antireflux defenses, including carbonic anhydrases (CAs I to IV) that appear to be protective against gastric reflux. This study aimed to investigate the expression and distribution of CA isoenzymes in laryngeal epithelium. Laryngeal biopsy specimens collected from the vocal fold and interarytenoid regions were analyzed by Western blotting and immunofluorescence. Carbonic anhydrases I and II were expressed by the majority of samples analyzed. In contrast, CA III was differentially expressed in the interarytenoid samples and was not detected in any vocal fold samples. The expression of CA III was increased in esophagitis as compared to normal esophageal tissue. Carbonic anhydrase I and III isoenzymes were distributed cytoplasmically in the basal and lower prickle cell layers. The laryngeal epithelium expresses some CA isoenzymes and has the potential to protect itself against laryngopharyngeal reflux. Laryngeal tissue may be more sensitive to injury due to reflux damage than the esophageal mucosa because of different responses of CA isoenzymes.

Expression of a small heat shock protein 27 (HSP27) in mouse skin tumors induced by UVB-irradiation

We investigated the expression of heat shock protein 27 (HSP27) at intermediate stages of a cutaneous tumor induced by UVB-irradiation stress (290-380 nm, max. 312 nm) using an immunostaining method. After 15-20 weeks of chronic exposure to UVB irradiation at a dose of 2 kJ/m2, HSP27 was found in the upper cell layers of bowenoid multilayers of epidermis, in areas of the lesions where normal stratification seems to be conserved. After 25 weeks, HSP27 was weakly expressed in squamous cell carcinoma (SCC). The HSP27 distribution patterns during cutaneous tumor progression resemble that of cytokeratin 10, a differentiation marker in keratinocytes. In SCC, a low degree of HSP27 expression was detected in the well-differentiated carcinomatous areas, but not in the poorly differentiated areas. These results indicate that the level of HSP27 decreases significantly as epithelial carcinoma growth progresses upon UVB-exposure. The expression of HSP27 may be associated with the onset of skin keratinocyte differentiation, but not with progression of SCC.

Heat shock protein expression in human tumours grown in severe combined immunodeficient mice

The constitutional expression of heat shock proteins (HSP) 27, 70 and 90 in human breast, colon and ovarian cancer cells transplanted into severe combined immunodeficient (SCID) mice was evaluated. In addition their induced expression under chemotherapeutic stress was analyzed. The oestrogen receptor positive breast cancer cell lines (MCF-7, T47D) demonstrated an increased level of HSP 27 and 70 expression compared with oestrogen receptor negative cell lines (BT20, HBL100). After 5-fluorouracil application for 4 days, HSP 27 and 70 expression was increased in HT29 colon tumours. Hence, the human/SCID mouse model is well suited to evaluate the constitutional and induced expression of human HSPs under various experimental conditions.

Clinical application of malignancy potential grading as a prognostic factor of human esophageal cancers

BACKGROUND

Various biologic markers have been reported to be prognostic factors in human esophageal cancers. In the current study, we established a new tumor-grading system representing the malignancy potential of cancer cells and compared it with the clinical-stage system.

METHODS

Tumor samples from 77 patients with squamous cell carcinoma of the esophagus were immunohistochemically evaluated for the expression of 10 molecules: the cell cycle-related molecules of cyclin D1, Rb, p16INK4, p27KIP1, and PCNA; the cell-cell adhesion molecules of E-cadherin, alpha-catenin, and beta-catenin; and the heat shock proteins of HSP27 and HSP70.

RESULTS

P27KIP1, beta-catenin, and HSP70 were selected for their high hazard ratio in multivariate analysis, and the number of their disordered molecules was used to define the malignancy grade (MG). Five-year survival rates were 83%, 54%, 17%, and 0% for MG1, MG2, MG3, and MG4. The gradation of survival curves was better for MGs than for clinical stages. MGs and clinical stages showed significant correlation; however, 55% of those in higher clinical stages (stage 3 or 4) had lower MG (MG1 or 2) and showed better prognosis than others in their group (stage 3 or 4 and MG3 or 4). The proportions of shorter survival span to cancer death patients (less than 1 year) were 0%, 33%, 75%, and 100% in MG1, 2, 3, and 4, but the clinical stage was not associated with the survival span.

CONCLUSIONS

The grading of malignancy potential is clinically useful, especially for selecting patients who may show good prognosis in the advanced clinical stage and for predicting short survival span. These predictions are not possible with the clinical-stage system, which is based on the anatomic spread of cancer cells.

Heat shock proteins in human cancer

The heat shock proteins (hsp) are ubiquitous molecules induced in cells exposed to sublethal heat shock, present in all living cells, and highly conserved during evolution. Their function is to protect cells from environmental stress damage by binding to partially denatured proteins, dissociating protein aggregates, to regulate the correct folding, and to cooperate in transporting newly synthesized polypeptides to the target organelles. The molecular chaperones are involved in numerous diseases, including cancer, revealing changes of expression. In this review, we mainly describe the relationship of hsp expression with human cancer, and discuss what is known about their post-translational modifications according to malignancies.

Small heat-shock proteins and their potential role in human disease

The elevated expression of stress proteins is considered to be a universal response to adverse conditions, representing a potential mechanism of cellular defense against disease and a potential target for novel therapeutics, including gene therapy and chaperone-modulating reagents. Recently, a single mutation in the small heat-shock protein human alphaB-crystallin was linked to desmin-related myopathy, which is characterized by abnormal intracellular aggregates of intermediate filaments in human muscle. New findings demonstrate that the high level of expression of stress proteins can contribute to an autoimmune response and can protect proteins that contribute to disease processes.