Tumor factors predicting for prognosis in metastatic breast cancer. The presence of P24 predicts for response to treatment and duration of survival

Study on the Prognostic Values of Dynactin Genes in Low-Grade Glioma

OBJECTIVE

This present study aims to investigate the potential prognostic values of dynactin genes (DCTN) for predicting the overall survival (OS) in low-grade glioma (LGG) patients.

METHODS

The DCTN mRNA expression data were downloaded from The Cancer Genome Atlas database containing 518 patients with LGG. The Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses for DCTN genes were performed by using Database for Annotation, Visualization, and Integrated Discovery platform, and their enrichment results were verified by using the Biological Networks Gene Ontology tool. Next, the correlations between DCTN genes and LGG were identified by Pearson correlation coefficient analysis. The OS was estimated by Kaplan-Meier survival analysis. The cBio Cancer Genomics Portal was used to analyze the mutations of DCTN genes and their effects on the prognosis of LGG. The correlation between the abundance of immune infiltration and tumor purity of DCTN genes were predicted by The Tumor Immune Estimation Resource.

RESULTS

Our research showed that the mRNA expression of DCTN4 in tumor tissues was much higher (P < 0.01) than that in normal tissues. Meanwhile, there was a certain correlation between the DCTN genes. Survival analysis showed that the high expression of DCTN1, DCTN3, DCTN4, DCTN6, and their co-expression were significantly correlated with favorable OS in LGG patients (P < 0.05). In DCTN2, a high mutation rate was observed. Further research showed that the genetic alteration in DCTN genes was related to a poor OS and progression-free survival of LGG patients. The expression of DCTN genes had a certain correlation with immune infiltrating cells.

CONCLUSION

Our study showed that the high expressions of DCTN1, DCTN3, DCTN4, and DCTN6 were associated with a favorable OS of LGG patients, indicating that these DCTN genes are potential biomarkers for evaluating the prognosis of LGG patients.

Tetraspanin CD9 is Regulated by miR-518f-5p and Functions in Breast Cell Migration and In Vivo Tumor Growth

Breast cancer is the most commonly diagnosed and the second leading cause of cancer-related mortality among women worldwide. miR-518f-5p has been shown to modulate the expression of the metastasis suppressor CD9 in prostate cancer. However, the role of miR-518f-5p and CD9 in breast cancer is unknown. Therefore, this study aimed to elucidate the role of miR-518f-5p and the mechanisms responsible for decreased CD9 expression in breast cancer, as well as the role of CD9 in de novo tumor formation and metastasis. miR-518f-5p function was assessed using migration, adhesion, and proliferation assays. miR-518f-5p was overexpressed in breast cancer cell lines that displayed significantly lower CD9 expression as well as less endogenous CD9 3'UTR activity, as assessed using qPCR and dual luciferase assays. Transfection of miR-518f-5p significantly decreased CD9 protein expression and increased breast cell migration in vitro. Cd9 deletion in the MMTV/PyMT mouse model impaired tumor growth, but had no effect on tumor initiation or metastasis. Therefore, inhibition of miR-518f-5p may restore CD9 expression and aid in the treatment of breast cancer metastasis.

Expression Profiling and Cellular Localization of Stress Responsive Proteins in Squamous Cell Carcinoma of Human Esophagus

BACKGROUND

The ambiguity in relating expression dynamics of stress response proteins with human esophageal squamous cell carcinoma (ESCC) has sidelined the potential of stress proteins as therapeutic targets. This study was an attempt to unequivocally relate the stress protein dynamics with stage and propensity of ESCC.

METHODS

Surgically resected tumor and adjacent histologically normal tissue from 46 patients with esophageal squamous cell carcinoma were investigated in the present study. Expression of HSPs was analyzed by Western blotting and immunohistochemistry.

RESULTS

HSP expression was observed in all 46 cases both in adjacent normal and tumor tissues. The expression and the localization of individual HSP showed no significant correlation with depth of invasion, tumor grade, and pathological stage of the tumor. HSP 27 was the most abundant protein followed by HSP 90 and HSP 70. The HSP 27 localized exclusively in the cytoplasm of adjacent normal and tumor cells. HSP 70 showed dispersed expression with predominating nuclear localization in both normal and tumor tissue cells and HSP 90 was localized in cytoplasm of adjacent normal and in nucleus of tumor cells in majority of the cases.

CONCLUSION

Our data advocate lack of relationship between stress protein expression and the progression of ESCC. The data renew the prospect of anti-HSP drugs as therapeutic resources in light of the possibility that their use would continue to sensitize cancer cells towards drug induced apoptosis for tumor regression.

Differential protein expressions in breast cancer between drug sensitive tissues and drug resistant tissues

OBJECTIVE

To investigate the differential expression of the sensitive and resistant relative proteins in human breast cancer tissue.

METHODS

A drug sensitive group and a drug resistant group for chemotherapy in patients with breast cancer were selected through neoadjuvant therapy. The differential protein expression in 2 groups was detected by proteomic techniques, and parts of differential proteins were identified by Western blotting.

RESULTS

There were 13 differential proteins in the 2 groups, in which the expression of 3 proteins was up-regulated and 10 down-regulated. Seven proteins were identified by Western blotting. The expressions of keratin type I cytoskeletal 19 (KIC19) and thymidine phosphorylase (TYPH) were up-regulated, and the expressions of heat shock protein 27 (HSP27), keratin type I cytoskeletal 9 (KIC9), collagen alpha-2(VI) (CO6A2), vimentin (VIME), and actin cytoplasmic 1 (ACTB) were down-regulated in the drug resistant group. There were significant differences between these 2 groups (P<0.01).

CONCLUSIONS

The expressions of KIC19 and TYPH may be correlated with drug resistance in patients with breast cancer, and HSP27, KIC9, CO6A2, VIME, and ACTB may be correlated with drug sensitivity.

Chromosome wide analysis of CUGBP1 binding sites identifies the tetraspanin CD9 mRNA as a target for CUGBP1-mediated down-regulation

CUGBP1 is an RNA-binding protein controlling alternative splicing, mRNA translation and stability. In this work we used a motif scoring approach to identify putative CUGBP1 binding sites for genes located on the human chromosome 12. This allowed us to identify the gene CD9 as a presumptive target for CUGBP1-mediated regulation. In a number of cancers, the tetraspanin CD9 is down-regulated, an event correlated with a bad prognostic. Using a combination of biochemical approaches and CUGBP1 knockdown, we showed that CUGBP1 directly controls CD9 expression.

Heat shock proteins in cancer: diagnostic, prognostic, predictive, and treatment implications

Heat shock proteins (Hsps) are overexpressed in a wide range of human cancers and are implicated in tumor cell proliferation, differentiation, invasion, metastasis, death, and recognition by the immune system. We review the current status of the role of Hsp expression in cancer with special emphasis on the clinical setting. Although Hsp levels are not informative at the diagnostic level, they are useful biomarkers for carcinogenesis in some tissues and signal the degree of differentiation and the aggressiveness of some cancers. In addition, the circulating levels of Hsp and anti-Hsp antibodies in cancer patients may be useful in tumor diagnosis. Furthermore, several Hsp are implicated with the prognosis of specific cancers, most notably Hsp27, whose expression is associated with poor prognosis in gastric, liver, and prostate carcinoma, and osteosarcomas, and Hsp70, which is correlated with poor prognosis in breast, endometrial, uterine cervical, and bladder carcinomas. Increased Hsp expression may also predict the response to some anticancer treatments. For example, Hsp27 and Hsp70 are implicated in resistance to chemotherapy in breast cancer, Hsp27 predicts a poor response to chemotherapy in leukemia patients, whereas Hsp70 expression predicts a better response to chemotherapy in osteosarcomas. Implication of Hsp in tumor progression and response to therapy has led to its successful targeting in therapy by 2 main strategies, including: (1) pharmacological modification of Hsp expression or molecular chaperone activity and (2) use of Hsps in anticancer vaccines, exploiting their ability to act as immunological adjuvants. In conclusion, the present times are of importance for the field of Hsps in cancer, with great contributions to both basic and clinical cancer research.

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.

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.

c-erb-B2 expression and response to treatment in metastatic breast cancer

The frequency of c-erb-B2 expression, clinical correlates and treatment outcome was investigated in 92 patients with metastatic breast cancer. Positive c-erb-B2 immunostaining was found in 24/92 (26%) of tumours. There was a statistically significant inverse correlation between c-erb-B2 expression and ER status. There was also a significant inverse correlation between c-erb-B2 expression and tumour free interval. c-erb-B2 expression had no influence on response to treatment with tamoxifen among patients co-expressing both c-erb-B2 and estrogen receptor (ER). Following chemotherapy (CAF) treatment there was a trend to a lower response rate among c-erb-B2+ as compared to c-erb-B2- patients. However, more c-erb-B2+ patients had received prior adjuvant chemotherapy, and when this factor was included in a multivariate analysis only prior adjuvant chemotherapy treatment predicted for response to CAF chemotherapy for metastatic disease. Time to treatment failure (TTF) was significantly shorter among cerb B2+ as compared to c-erb-B2- patients. The current study suggests that the c-erb-B2 expression is found at similar frequency in metastatic as in primary breast cancer. Although c-erb-B2 expression did not predict for response to either hormonal therapy or to chemotherapy for metastatic disease, patients with c-erb-B2+ metastatic lesions appear to have a more aggressive clinical course.

Heat-shock-protein-27 (hsp27) expression in ovarian carcinoma: relation in response to chemotherapy and prognosis

Heat-shock protein 27 (hsp27) is one of the small heat-shock proteins. Its expression in ovarian- and breast-cancer cell lines has been associated with resistance to cisplatin and doxorubicin. In addition, hsp27 expression appears to facilitate cellular growth, differentiation and motility. In several human carcinomas, hsp27 expression might also be related to worse prognosis. The aim of this study was to evaluate the prognostic value of hsp27 expression in patients with ovarian carcinoma in relation to their response to chemotherapy and overall survival. Hsp27 expression was assessed by immunohistochemistry in 77 patients with ovarian carcinoma stage IC-IV. All patients received cisplatin- and doxorubicin-based chemotherapy and had long-term follow-up. In 30 patients, paired tumour samples were available, obtained before and after chemotherapy. Hsp27 immunostaining was positive in 86% of patients before and in 72% of patients after chemotherapy. Hsp27 expression was not related to any clinicopathologic factor, including previously determined p53 expression. Univariate analysis showed that, in stage-III and -IV patients, younger age, no residual tumour after first laparotomy, < or = 1 litre ascites, response to first-line chemotherapy and absence of hsp27 expression were associated with longer median progression-free survival. However, in multivariate analysis, only age, ascites and response to chemotherapy retained independent prognostic value.

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

BACKGROUND

Heat shock proteins (HSPs) first were defined as proteins induced by heat shock and other environmental and pathophysiologic stresses and are implicated in protein-protein interactions such as folding, translocation, and prevention of inappropriate protein aggregation. Many of their functions suggest that they play important roles in cancer.

METHODS

Immunohistochemical study for HSP 27 and HSP 70 was performed on buffered formalin fixed, paraffin embedded sections of 102 esophageal squamous cell carcinoma specimens using monoclonal anti-HSP 27 antibody and anti-HSP 70 antibody.

RESULTS

Normal squamous cells expressed both HSP 27 and HSP 70 with the exception of the basal layer. In cancerous tissue, expression of HSP 27 was evaluated as positive (+) (39 cases; 38%), reduced (+/-) (53 cases; 52%), or negative (-) (10 cases; 10%) and expression of HSP 70 was evaluated as (+) (14 cases; 14%), (+/-) (57 cases; 56%), or (-) (31 cases; 30%). There was a strong correlation between the expression of HSP 27 and HSP 70 (P < 0.0001). When compared with clinicopathologic features, expression of both HSP 27 and HSP 70 correlated negatively with lymph node metastases (P < 0.05), but not with depth of invasion or histologic grade. The reduction of the HSPs was associated significantly with poor postoperative survival (P < 0.0001). In addition, multivariate analysis revealed that HSP 27 (-) was the strongest prognostic factor among the clinicopathologic features.

CONCLUSIONS

This study suggests that the expression of HSP 27 and HSP 70 frequently is reduced in patients with esophageal squamous cell carcinoma and therefore should be considered an independent prognostic factor of this disease.

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

BACKGROUND

Heat shock proteins (HSPs) first were defined as proteins induced by heat shock and other environmental and pathophysiologic stresses and are implicated in protein-protein interactions such as folding, translocation, and prevention of inappropriate protein aggregation. Many of their functions suggest that they play important roles in cancer.

METHODS

Immunohistochemical study for HSP 27 and HSP 70 was performed on buffered formalin fixed, paraffin embedded sections of 102 esophageal squamous cell carcinoma specimens using monoclonal anti-HSP 27 antibody and anti-HSP 70 antibody.

RESULTS

Normal squamous cells expressed both HSP 27 and HSP 70 with the exception of the basal layer. In cancerous tissue, expression of HSP 27 was evaluated as positive (+) (39 cases; 38%), reduced (+/-) (53 cases; 52%), or negative (-) (10 cases; 10%) and expression of HSP 70 was evaluated as (+) (14 cases; 14%), (+/-) (57 cases; 56%), or (-) (31 cases; 30%). There was a strong correlation between the expression of HSP 27 and HSP 70 (P < 0.0001). When compared with clinicopathologic features, expression of both HSP 27 and HSP 70 correlated negatively with lymph node metastases (P < 0.05), but not with depth of invasion or histologic grade. The reduction of the HSPs was associated significantly with poor postoperative survival (P < 0.0001). In addition, multivariate analysis revealed that HSP 27 (-) was the strongest prognostic factor among the clinicopathologic features.

CONCLUSIONS

This study suggests that the expression of HSP 27 and HSP 70 frequently is reduced in patients with esophageal squamous cell carcinoma and therefore should be considered an independent prognostic factor of this disease.

A study of heat shock protein 27 in endometrial carcinoma

OBJECTIVE

Heat shock protein 27 (HSP27) is a relatively small protein produced in response to pathophysiologic stress. The purpose of this study was to determine prospectively whether HSP27 was associated with known prognostic factors in patients with endometrial carcinoma.

METHODS

One hundred fifty-three consecutive patients with endometrial carcinoma were studied. Slides were prepared from fresh tissue. HSP27 was analyzed using a semiquantitative measurement. Patient records were examined for FIGO stage, grade, depth of myometrial invasion, histology, lymphovascular space invasion, time to recurrence, and survival.

RESULTS

The mean follow-up was 53 months (median 56 months, range 30-68 months). Endometrioid tumors showed significantly higher HSP27 staining than nonendometrioid tumors (P = 0.005). Patients alive at the conclusion of this study had significantly higher mean HSP27 staining than patients who were deceased (P < 0.001). Logistic regression revealed HSP27 staining (P = 0.02), FIGO stage (P = 0. 014), and lymphovascular space invasion (P = 0.046) to be independently predictive of survival.

CONCLUSION

HSP27 staining is significantly higher in endometrioid than nonendometrioid tumors. HSP27 staining is an independent prognostic indicator in patients with endometrial carcinoma, the most common gynecologic malignancy in the United States.

Heat shock protein expression and drug resistance in breast cancer patients treated with induction chemotherapy

Heat shock proteins (Hsps) are induced in vitro by several cytotoxic drugs; in human breast cancer cells these proteins appear to be involved in anti-cancer drug resistance. The present report was designed to analyze whether chemotherapy affects in vivo the expression of Hsp27, Hsp70, Hsc70 and Hsp90 in breast cancer patients treated with induction chemotherapy and whether these proteins may be determinants of tumor resistance to drug administration. We have analyzed 35 biopsies from breast cancer patients treated with induction chemotherapy. Expression of the Hsps in the tumors was compared with (i) histological and clinical responses to chemotherapy, (ii) tumor cell proliferation measured by proliferating cell nuclear antigen (PCNA) immunostaining and nucleolar organizer regions (AgNORs) staining and (iii) the expression of estrogen and progesterone receptors. We also compared disease-free survival (DFS) and overall survival (OS) with the expression of the Hsps studied. After chemotherapy, nuclear Hsp27 and Hsp70 expression was increased and Hsp70 and Hsc70 cytoplasmic expression was decreased. A high nuclear proportion of Hsp70 in tumor cells (>10%) correlated significantly with drug resistance. We also observed that patients whose tumors expressed nuclear or a high cytoplasmic proportion (>66%) of Hsp27 had shorter DFS. The combination of Hsp27 and Hsp70 levels showed a strong correlation with DFS. Neither the cellular proliferation nor the levels of steroid receptors showed any significant difference before or after drug administration or during follow-up of patients. Our results suggest that Hsp27 and Hsp70 are involved in drug resistance in breast cancer patients treated with combination chemotherapies.

Heat shock protein 27: an independent prognostic indicator of survival in patients with epithelial ovarian carcinoma

OBJECTIVE

Heat shock protein 27 (HSP27) is produced in response to pathophysiologic stress in animal cells. The purpose of this study was to determine prospectively whether HSP27 was associated with known prognostic factors as well as survival in patients with epithelial ovarian carcinoma.

METHODS

Ninety-nine patients with epithelial ovarian carcinoma were studied. Slides were prepared from fresh tissue. Patient records were examined for FIGO stage, grade, histology, level of cytoreduction, and survival.

RESULTS

Immunohistochemical staining for HSP27 was not related to histologic grade, level of cytoreduction or histologic subtype. A statistically significant difference in HSP27 staining was found in relation to FIGO stage (P = 0.013). HSP27 staining was found to be an independent predictor of 2-year survival in these patients (P = 0.041).

CONCLUSION

The level of HSP27 significantly decreases as the FIGO stage increases and is an independent prognostic indicator of survival in patients with epithelial ovarian carcinoma.

Comparison of tumor growth between hsp25- and hsp27-transfected murine L929 cells in nude mice

We have developed a novel system for examining the possible contribution of small heat shock proteins (hsp) to tumor growth. L929 fibrosarcoma cells, which do not express significant levels of endogenous hsp25, were stably transfected with either murine hsp25 or human hsp27. Both transfected genes were over-expressed and the respective proteins were phosphorylated in L929 cells. L929 cells transfected with hsp25 exhibited enhanced tumor growth compared to control transfected L929 cells upon s.c. injection into nude mice. In contrast, cells transfected with hsp27 exhibited delayed tumor progression in comparison to controls. Although these 2 heat shock genes and respective proteins are structurally very similar, they apparently exhibit distinct effects on tumor growth in this system.

Loss of expression of a 55 kDa nuclear protein (nmt55) in estrogen receptor-negative human breast cancer

We have identified and characterized a 55 kDa nuclear protein (referred to as nmt55) from human breast tumors and MCF-7, human adenocarcinoma breast cell line, using site-directed monoclonal antibodies. Measurements of estrogen receptors (ER) and progesterone receptors (PR), by ligand binding assays, in cytosols of 63 human breast tumors permitted classifications of these tumors into four phenotypes (ER+/PR+, ER+/ PR-, ER-/PR-, ER-/PR+). Nuclear protein (nmt55) expression in these tumors, as determined from Western blot analyses, showed a statistically significant association (p = 0.001) with tumor hormonal phenotype. Review of the pathologic characteristics of tumors analyzed suggested that lack of nmt55 expression was significantly associated with mean tumor size (p < 0.03), mean ER (p = 0.001) and mean PR (p < 0.002), but was not associated with tumor stage, grade, or type. To further study this protein, we cloned and sequenced a 2.5 kb cDNA using a monoclonal antibody to nmt55. The complete predicted open reading frame encodes a protein with 471 amino acids and a calculated molecular mass of 54,169 Da. The deduced amino acid sequence exhibited unique regions rich in glutamine, histidine, arginine, and glutamic acid. Northern blot analysis of RNA from MCF-7 cells and ER+/PR+ human breast tumors showed a 2.6 kb mRNA. Southern blot analysis suggested the presence of a single copy of this gene. Chromosomal mapping, using fluorescent in situ hybridization (FISH), located nmt55 gene to the X chromosome, region q13. The extensive homology between nmt55 and RNA binding proteins suggested that nmt55 may be involved in hnRNA splicing. The strong association observed between expression of nmt55, tumor hormonal phenotype, mean tumor size, mean ER, and mean PR content suggests that loss of nmt55 expression may be related to events involved in hormone insensitivity, tumor differentiation, and unregulated tumor cell growth and metastases.

Chemotherapy-induced expression of alpha B-crystallin in neuroblastoma

Since alpha B-crystallin is known to be expressed in glial tissues of human brain and neuroectodermal tumors, the alpha B-crystallin content of neuroblastomas, may be related to the degree of glial or neuronal differentiation. The alpha B-crystallin content of 73 neuroblastomas, was determined by enzyme immunoassay. The concentration of alpha B-crystallin was examined in light of neuroblastoma prognostic factors. Neuroblastomas from patients who received chemotherapy (n = 23) contained higher concentrations of alpha B-crystallin than those from patients who did not receive chemotherapy (n = 50) (P > 0.05). There was a statistically significant difference in alpha B-crystallin concentrations in advanced stage patients who received preoperative chemotherapy (P < 0.01). Immunohistochemistry demonstrated alpha B-crystallin expression in the nerve-like fibers and a few ganglion-like cells. Staining was not apparent in the less differentiated cells in the tumor cell nest. alpha B-crystallin may play a role in the response to cellular stress in neuroblastoma.

Lack of relationship between the expression of Hsp27 heat shock estrogen receptor-associated protein and estrogen receptor or progesterone receptor status in male breast carcinoma

Estrogen, through estrogen receptors (ERs), may regulate the synthesis of progesterone receptors (PRs) and of a heat shock estrogen receptor-associated protein (hsp27). In female breast carcinoma (FBC) both proteins serve as surrogate indicators for the presence of functional ERs. In addition, the expression of these proteins was related to other prognostic indicators of value in female breast tumours. Endocrine disorders, hormone therapy and altered estrogen metabolism have been associated with the development of male breast cancer (MBC), suggesting that evaluation of the expression of ER, PR and hsp27 might improve our understanding of the biology of this tumour. ER and PR status and hsp27 expression were evaluated by immunohistochemistry in 16 primary MBC patients. The interrelationships between these parameters were established and compared with the clinicopathological data on the tumours. Ten (56%) MBC patients were ER-positive, 69% were PR-positive and all samples were hsp27-positive. Our series of MBC patients showed a positive correlation between ERs and PRs, however there was a lack of correlation between hsp27 and ERs or PRs. MBCs did not exhibit any correlation between the biomarkers studied and known prognostic indicators for females (e.g. Scarff-Bloom-Richardson (SBR) or modified SBR (MSBR) grade, T stage, lymph node status). This is the first published series reporting the incidence of hsp27 in MBC. The lack of association between the expression of ERs and hsp27 found in MBC differs from the results reported for FBC, moreover the expression of ERs, PRs or hsp27 did not correlate with the clinicopathological parameters that have prognostic value in females. Although the data were obtained from a relatively small sample population, our findings suggest that MBC and FBC are biologically different tumours with respect to the expression of the studied proteins.

Heat-shock protein expression in cisplatin-sensitive and -resistant human tumor cells

It has been suggested that the expression of certain heat-shock proteins (HSPs) may be prognostic markers in several tumor types. Since HSPs may be involved in determining cellular sensitivity to chemotherapeutic drugs, the possible relation between HSP expression and cisplatin (cDDP) sensitivity was studied. Three human germ-cell tumor cell lines, 1 human small-cell lung carcinoma (SCLC) cell line and 3 human colon carcinoma cell lines were used as a model for differences in intrinsic cDDP sensitivity. The constitutive expression of a panel of HSPs was studied by immunoblotting. No correlation was found between expression of HSP90, HSP73, HSP72, HSP60 and HSP27 and the extent of intrinsic cDDP sensitivity when all cell lines studied were considered. However, for the 3 cell lines derived from germ-cell carcinomas, HSP27 expression was inversely related to cDDP sensitivity; ie. decreased HSP27 levels were associated with decreased sensitivity. Constitutive HSP expression was also studied in 2 sets of human cell lines with in vitro acquired cDDP resistance. In both resistant cell lines, decreased expression of HSP27 (as determined by Western blotting) was found as compared to the sensitive parent cell lines. Thus, acquired resistance to cDDP was also accompanied by decreased HSP27 expression. Interestingly, when basal HSP27 mRNA levels were measured in the SCLC cell line (GLC4) and its subline with acquired resistance (GLC4-cDDP), no significant differences were detected. Continuous cDDP incubation increased HSP27 levels and induced HSP27 phosphorylation in GLC4 cells, but not in the resistant subline. Thus, although no general relationships between HSP expression and cDDP sensitivity are apparent, high HSP27 expression in vitro relates to high sensitivity to cDDP treatment in some tumor types. This is in accordance with reported clinical data on high HSP27 levels in tumors correlating with good prognosis.

Do heat shock proteins have a role in breast cancer?

It is clear therefore that hsps are overexpressed in patients with malignant tumours compared with healthy controls and this overexpression does show some correlation with disease features. Furthermore, expression of hsps has been reported on the cell surface of tumour cell lines. This could be associated with the immune response which has been reported with hsp90 and which also correlates with some disease features. It now appears that hsps may be involved in the presentation of tumour antigens leading to the possibility of hsps being used as a means of therapy. Hsp65 expression has not been investigated in patients with breast cancer. However, transfection of bacterial hsp65 into a tumour cell line resulted in the hsp65-expressing tumour cells losing their tumorigenicity in mice (Lukacs et al., 1993). Thus, hsps and the immune response to them are of interest as diagnostic and prognostic tools as well as a novel form of immunotherapy.

P-glycoprotein immunostaining correlates with ER and with high Ki67 expression but fails to predict anthracycline resistance in patients with advanced breast cancer

In an attempt to further define the clinical utility of p-glycoprotein immunostaining in breast cancer, we examined 101 specimens from patients with advanced breast cancer. There was a significant correlation between estrogen receptor status and p-glycoprotein expression but only for low levels of p-glycoprotein. Premenopausal status appeared to correlate with increased p-glycoprotein expression, but this probably reflects patient selection as premenopausal patients had higher prior exposure to anthracyclines and were more likely to have received chemotherapy as initial treatment. P-glycoprotein expression was highly significantly correlated with expression of the proliferation related antigen Ki67, suggesting that p-glycoprotein expression may well be cell cycle dependent, with overexpression occurring in rapidly cycling cells. These findings may explain reported findings of modulation of p-glycoprotein expression by agents such as anti-oestrogens. P-glycoprotein positive staining did not, however, predict chemotherapy treatment failure or survival duration.

Prognostic significance of heat-shock protein-27 in node-positive breast carcinoma: an immunohistochemical study

Immunostaining for heat-shock protein-27 (HSP-27) was performed on formalin fixed-paraffin embedded sections of 890 node-positive breast carcinomas resected between 1980 and 1986. The follow-up ranged from 2.5 to 10.5 years. A polyclonal antibody (Hu27, dilution: 1/200) was used. A positive cytoplasmic staining was obtained in 383 cases (43%). No difference in distant metastasis-free survival (DMFS) or overall survival (OS) was noted between cases with positive or negative immunostaining. This study suggests that HSP-27 expression is not predictive of the outcome in node-positive breast cancer.

Positive immunostaining for platelet derived growth factor (PDGF) is an adverse prognostic factor in patients with advanced breast cancer

Previous studies suggest a prognostic role for PDGF in patients with breast cancer, with patients with high plasma PDGF levels or positive response to therapy. We have examined a further 58 patients with advanced breast cancer for the presence of tissue PDGF immunostaining. Patients displaying positive tissue immunostaining for PDGF had a highly significant shorter survival (p = 0.002) than patients with no immunostaining. In addition PDGF positive patients treated with combination chemotherapy had a significantly lower response rate (p = 0.05) than PDGF negative patients. These results confirm our previous findings that PDGF may be an important indicator of shortened survival and treatment failure in patients with advanced breast cancer.

Oestrogen receptor, progesterone receptor, pS2, ERD5, HSP27 and cathepsin D in invasive ductal breast carcinomas

Hormonal receptors and markers for prognostic evaluation were detected immunohistochemically in 196 infiltrating ductal breast carcinomas. Immunohistochemical detection of progesterone and oestrogen receptor is a method giving results generally concordant with those of the binding assay. However, immunohistochemical detection seems better. It allows the detection of hormonal receptors on small carcinomas, it is not modified by the endogenous hormones, and it has a slightly better correlation with prognosis and with the response to hormone therapy. Immunohistochemical detection of progesterone receptor has a prognostic value, sorting a negative subgroup with a poor prognosis from the oestrogen receptor positive tumours. These results can be obtained without quantitative immunohistological methods. ERD5, pS2, HSP27 and cathepsin D are associated with oestrogen receptor positivity. pS2 and HSP27 are interesting markers. They characterize a subgroup of oestrogen receptor negative tumours with a good prognosis. Moreover, pS2 is a marker of response to hormone therapy. ERD5 and cathepsin D do not appear to be of value as markers of prognosis.

Interferon plus tamoxifen treatment for advanced breast cancer: in vivo biologic effects of two growth modulators

The effects of interferon-alpha (IFN) plus tamoxifen (TMX) in the treatment of advanced breast cancer were assessed. Changes of in vivo biologic determinants including hormone receptors, P24 protein, Ki-67 and growth factor expression were evaluated. Seven patients with advanced, heavily pretreated, breast cancer with accessible disease, underwent biopsy prior to and after sequential treatment with IFN and IFN plus TMX. Clinically 4/7 patients responded to treatment with one complete and three partial remissions. Apart from the favourable response rate the sequential in vivo changes in expression of tumour variables were of considerable interest. IFN treatment consistently increased the expression of the estrogen receptor (ER) and of the estrogen regulated protein P24 while decreasing the expression of the proliferation associated antigen Ki-67. Addition of TMX on the other hand resulted in a reduction of ER expression to pre-IFN levels and a rise in progesterone receptor (PR) expression. When the effect of either IFN or IFN plus TMX on the expression of two growth factors was assessed they were found to be somewhat variable. While PDGF expression tended to be suppressed, there was no clinical correlation with response to therapy. TGF beta expression was found in all patients prior to treatment and while all non-responders showed reduction of TGF beta following treatment, the alterations were variable amongst responders (including two patients with increased expression, one with no change, and one with decreased expression). It is concluded that both IFN and TMX exert multiple effects on the expression of tumour biologic variables and that while the study confirmed some of the predictions from in vitro models, the in vivo effect are more complex than has been appreciated from the models. From the clinical point of view, it might be expected that treatment which enhances the expression of ER in tumours should have a positive effect on the response to TMX.

Markers of prognosis in breast cancer--the relationship between binding of the lectin HPA and histological grade, SPF, and ploidy

Abnormal cellular glycosylation as demonstrated by the binding of a lectin from Helix pomatia (HPA) to paraffin-embedded sections has been shown in several studies to be associated with aggressive biological behaviour and poor long-term patient prognosis in breast cancer. This study aims to address the possibility that expression of the HPA binding ligand may be of prognostic significance through an association with increased cellular proliferation (as measured by S-phase fraction and histological grade), anaplasia (reflected in histological grade), or ploidy (DNA index). In a 24 year retrospective study, paraffin-embedded sections of 366 primary breast cancers were stained for binding of HPA. All tumours were assessed for histological grade. Flow cytometry was performed on all cases for which sufficient tumour tissue was available (358/366 cases) and S-phase fraction (SPF) and ploidy calculated. Data regarding patient age at diagnosis, nodal status, and tumour size were also recorded. Life table analyses revealed survival advantage for HPA 'non stainers' in comparison to 'stainers' (p < 0.001); for patients with tumours of low grade vs. high grade (p < 0.001); and for those with tumours of low SPF vs. high SPF (p < 0.001). No survival advantage was shown for those with diploid vs. aneuploid tumours (p = 0.17). No association was apparent between HPA binding and grade, SPF, or ploidy (Chi squared values not significant). This was confirmed by multivariate analysis in which nodal status, tumour size, and SPF were independently predictive of survival. There was no confounding effect of grade, SPF, or ploidy upon the correlation between survival and HPA binding. HPA was, however, not independently predictive owing to its strong association with nodal status. The results of this study suggest that the prognostic significance of altered glycosylation, as detected by HPA binding, is unlikely to be through an association with proliferative rate, degree of anaplasia, or cellular ploidy, but may rather be through a direct association with the presence of nodal metastases.