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Members of the 90-kDa heat shock protein (HSP90) family are known to bind and stabilize intermediates in a wide variety of cell signaling pathways and contribute to their dysregulation in cancer. An important intracellular cofactor for HSP90 is Cdc37, a protein with a broad role in fostering the activities of protein kinases. By targeting Cdc37 using RNA interference, we have shown that the loss of Cdc37 function induces irreversible growth arrest in androgen receptor-positive and -negative prostate carcinoma cells. In contrast to HSP90-directed agents, Cdc37 targeting seems to affect cancer cells through a distinct mechanism and does not significantly deplete the intracellular levels of most known HSP90 client proteins. Instead, Cdc37 depletion inhibits cellular kinase activity and flux through growth-promoting signal transduction cascades. We show that the loss of Cdc37 leads to reduced activity of the Erk, Akt, mTOR, and androgen-induced pathways. We have also discovered synergistic interactions between Cdc37 inactivation and the HSP90-inhibitory anticancer drug 17-(allylamino)-17-demethoxygeldanamycin (17AAG). These interactions involve enhanced degradation of proteins essential for growth and inhibition of 17AAG-induced expression of the antiapoptotic HSP70. Thus, Cdc37 is essential for maintaining prostate tumor cell growth and may represent a novel target in the search for multitargeted therapies based on the HSP90 chaperone system. [Cancer Res 2007;67(24):11942–50]

Supplementary Figure 1 from Targeting Cdc37 Inhibits Multiple Signaling Pathways and Induces Growth Arrest in Prostate Cancer Cells

Aim Pancreatic ductal adenocarcinoma (PDAC) is often diagnosed at a late, incurable stage. We sought to determine whether individuals at high risk of developing PDAC could be identified early using routinely collected data. Methods Electronic health record (EHR) databases from two independent hospitals in Boston, Massachusetts, providing inpatient, outpatient, and emergency care, from 1979 through 2017, were used with case–control matching. PDAC cases were selected using International Classification of Diseases 9/10 codes and validated with tumour registries. A data-driven feature selection approach was used to develop neural networks and L2-regularised logistic regression (LR) models on training data (594 cases, 100,787 controls) and compared with a published model based on hand-selected diagnoses (‘baseline’). Model performance was validated on an external database (408 cases, 160,185 controls). Three prediction lead times (180, 270 and 365 days) were considered. Results The LR model had the best performance, with an area under the curve (AUC) of 0.71 (confidence interval [CI]: 0.67–0.76) for the training set, and AUC 0.68 (CI: 0.65–0.71) for the validation set, 365 days before diagnosis. Data-driven feature selection improved results over ‘baseline’ (AUC = 0.55; CI: 0.52–0.58). The LR model flags 2692 (CI 2592–2791) of 156,485 as high risk, 365 days in advance, identifying 25 (CI: 16–36) cancer patients. Risk stratification showed that the high-risk group presented a cancer rate 3 to 5 times the prevalence in our data set. Conclusion A simple EHR model, based on diagnoses, can identify high-risk individuals for PDAC up to one year in advance. This inexpensive, systematic approach may serve as the first sieve for selection of individuals for PDAC screening programs.

We describe a cell damage‐induced phenotype in mammary carcinoma cells involving acquisition of enhanced migratory and metastatic properties. Induction of this state by radiation required increased activity of the Ptgs2 gene product cyclooxygenase 2 (Cox2), secretion of its bioactive lipid product prostaglandin E2 (PGE2), and the activity of the PGE2 receptor EP4. Although largely transient, decaying to low levels in a few days to a week, this phenotype was cumulative with damage and levels of cell markers Sca‐1 and ALDH1 increased with treatment dose. The Sca‐1+, metastatic phenotype was inhibited by both Cox2 inhibitors and PGE2 receptor antagonists, suggesting novel approaches to radiosensitization.

Purpose To determine the effect of treatment changes over time on all-cause mortality risk in patients with early-stage Hodgkin lymphoma (HL) after radiation therapy. The long-term survivorship of those with HL necessitates quantification of the late risk of mortality from HL and other causes. Methods and Materials An institutional review board–approved retrospective study was conducted using a multi-institutional database of 1541 stage I and II HL patients treated from 1968 to 2007 with radiation therapy alone or combined-modality treatment. The analytic methods included cumulative incidence function, Kaplan-Meier estimates and log-rank tests for overall survival (OS) differences, and Cox proportional hazards modeling. Results The median age at diagnosis was 27 years. At a median follow-up of 15.2 years (35% of patients with >20 years of follow-up), 395 patients had died of all causes, including 85 HL, 168 second malignancy (25 hematologic and 143 nonhematologic), 70 cardiovascular, and 21 pulmonary deaths. The cumulative incidence of non-HL mortality had surpassed HL mortality at 8.3 years. For patients treated from 1968 to 1982, 1983 to 1992, and 1993 to 2007, the 15-year OS rates were 78%, 85%, and 88%, respectively (P=.0016). On Cox proportional hazards analysis, age, B symptoms, and number of disease sites were significantly associated with all-cause mortality in the first decade of follow-up, with a trend toward significance for radiation field extent. Conclusions The all-cause mortality risk was significantly lower for patients treated in the most recent era during the first decade of follow-up, likely due to improved HL therapy resulting in a higher cure rate and lower treatment-related toxicity from smaller radiation fields. Current efforts toward radiation treatment reduction might further reduce the long-term mortality risk for these patients.

To quantify the incidence of thyroid cancer after Hodgkin lymphoma (HL) and determine disease characteristics, risk factors, and treatment outcomes.Thyroid cancer cases were retrospectively identified from a multi-institutional database of 1981 HL patients treated between 1969 and 2008. Thyroid cancer risk factors were evaluated by a Poisson regression model.With a median follow-up duration of 14.3 years (range, 0-41.2 years), 28 patients (1.4%) developed a thyroid malignancy. The overall incidence rate (expressed as the number of cases per 10,000 person-years) and 10-year cumulative incidence of thyroid cancer were 9.6 and 0.26%, respectively. There were no observed cases of thyroid malignancy in patients who received neck irradiation for HL after age 35 years. Age20 years at HL diagnosis and female sex were significantly associated with thyroid cancer. The incidence rates of females aged20 at HL diagnosis in the first 10 years, ≥10 years, ≥15 years, and ≥20 years after treatment were 5, 31, 61, and 75 cases per 10,000 person-years of follow-up, respectively. At a median follow-up of 3.5 years after the thyroid cancer diagnosis, 26 patients (93%) were alive without disease, 1 (4%) was alive with metastatic disease, and 1 (4%) died of metastatic disease, at 6 and 3.6 years after the thyroid cancer diagnosis, respectively.Although HL survivors have an increased risk for thyroid cancer, the overall incidence is low. Routine thyroid cancer screening may benefit females treated at a young age and ≥10 years from HL treatment owing to their higher risk, which increases over time.

Molecular chaperone-based vaccines offer a number of advantages for cancer treatment. We have discussed the deployment of a vaccine prepared by gentle isolation of Hsp70 from tumour dendritic cell fusions (Hsp70 fusion vaccine). The vaccine was highly effective in triggering specific T cell immunity and in the treatment of tumour-bearing mice and the preparation was shown to retain an increased amount of tumour antigens compared to other chaperone-based isolates. This approach has the further advantage that tumour sub-populations could be used to prepare the Hsp70 fusion vaccine. Cellular fusion vaccines were made to specifically target drug-resistant cancer cells and tumour cell populations enriched in ovarian cancer stem cells (CSC). Such vaccines showed enhanced capacity to trigger T cell immunity to these resistant ovarian carcinoma populations. We have discussed the potential of using the cellular and Hsp70 fusion vaccine approaches in therapy of treatment-resistant cancer cells and its deployment in combination with ionising radiation or hyperthermia to enhance the effectiveness of both forms of therapy.

To review the epidemiology, pathophysiology, clinical features, and management of type B insulin resistance syndrome.Type B insulin resistance syndrome is a rare disorder caused by autoantibodies to the insulin receptor. This disorder is most frequently reported in middle-aged black women and is invariably associated with other autoimmune diseases. Typically, refractory transient hyperglycemia and extreme insulin resistance are the cardinal features, but hypoglycemia may also occur. Traditionally, the high reported mortality rate was typically attributed to the hypoglycemia. There is no well standardized treatment regimen. However, recent therapeutic advances with combination immunomodulatory therapy have led to significant reported improvements in hypoglycemia-associated mortality and durability of remission.We review the literature on the pathophysiology and clinical features of type B insulin resistance syndrome and highlight the complexities and recent advances in the management of this disorder.

Purpose Stereotactic radiosurgery (SRS) is an effective alternative to microsurgical resection or embolization for definitive treatment of arteriovenous malformations (AVMs). Digital subtraction angiography (DSA) is the gold standard for pretreatment diagnosis and characterization of vascular anatomy, but requires rigid frame (skull) immobilization when used in combination with SRS. With the advent of advanced proton and image-guided photon delivery systems, SRS treatment is increasingly migrating to frameless platforms, which are incompatible with frame-based DSA. Without DSA as the primary image, target definition may be less than optimal, in some cases precluding the ability to treat with a frameless system. This article reports a novel solution. Methods and Materials Fiducial markers are implanted into the patient’s skull before angiography. Angiography is performed according to the standard clinical protocol, but, in contrast to the previous practice, without the rigid frame. Separate images of a specially designed localizer box are subsequently obtained. A target volume projected on DSA can be transferred to the localizer system in three dimensions, and in turn be transferred to multiple CT slices using the implanted fiducials. Combined with other imaging modalities, this “virtual frame” approach yields a highly precise treatment plan that can be delivered by frameless SRS technologies. Results Phantom measurements for point and volume targets have been performed. The overall uncertainty of placing a point target to CT is 0.4 mm. For volume targets, deviation of the transformed contour from the target CT image is within 0.6 mm. The algorithm and software are robust. The method has been applied clinically, with reliable results. Conclusions A novel and reproducible method for frameless SRS of AVMs has been developed that enables the use of DSA without the requirement for rigid immobilization. Multiple pairs of DSA can be used for better conformality. Further improvement, including using nonimplanted fiducials, is potentially feasible.

Molecular chaperone-peptide complexes extracted from tumors (heat shock protein [HSP] vaccines) have been intensively studied in the preceding two decades, proving to be safe and effective in treating a number of malignant diseases. They offer personalized therapy and target a cross-section of antigens expressed in patients' tumors. Future advances may rely on understanding the molecular underpinnings of this approach to immunotherapy. One property common to HSP vaccines is the ability to stimulate antigen uptake by scavenger receptors on the antigen-presenting cell surface and trigger T-lymphocyte activation. HSPs can also induce signaling through Toll-Like receptors in a range of immune cells and this may mediate the effectiveness of vaccines.

This study assessed the cumulative incidence of clinically significant cardiac disease in 1279 Hodgkin lymphoma patients treated with mediastinal irradiation and quantified the standard incidence ratios (SIRs) and absolute excess risks of cardiac procedures compared with a normal matched population. Cox regression analysis was used to explore factors associated with cardiac complications. Poisson regression analysis of SIRs was used to estimate the excess risk of cardiac interventions from mediastinal irradiation. After a median follow-up of 14.7 years, 187 patients experienced 636 cardiac events and 89 patients required a cardiac procedure. 5-, 10-, 15-, and 20-year cumulative incidence rates of cardiac events were 2.2%, 4.5%, 9.6%, and 16%. SIRs for cardiac procedures were increased for coronary artery bypass graft (3.19), percutaneous intervention (1.55), implantable cardioverter defibrillator or pacemaker placement (1.9), valve surgery (9.19), and pericardial surgery (12.91). Absolute excess risks were 18.2, 19.3, 9.4, 14.1, and 4.7 per 10 000 person-years, respectively. Older age at diagnosis and male sex were predictors for cardiac events. However, younger age at diagnosis was associated with excess risk specifically from radiation therapy compared with the general population. These results may help guideline development for both the types and timing of cardiac surveillance in survivors of Hodgkin lymphoma.

To determine the radiation dose-response relationship on salivary dysfunction and quality of life (QOL) over time in patients with lymphoma receiving radiation therapy (RT) to the head and neck (HN).We conducted a prospective study on salivary-gland function in lymphoma patients receiving RT to the HN. Fifteen patients were enrolled on the study. Dose-volume histograms and mean doses to the salivary glands were generated. Radiation-related toxicities and HN-specific QOL were assessed before treatment and at prespecified time points posttreatment. Factors predicting a decrement in QOL were explored using Fisher's exact test.During RT, 47% of patients experienced Gradeor= 2 acute toxicity of the salivary gland, mucous membrane, or both. QOL scores improved over time, but up to one third of patients continued to have persistent oral symptoms at 2 years. At 6 months, a mean dose to at least one of the parotids of31 Gy was significantly associated with persistent dry mouth (100% vs. 17%, p = 0.02) and sticky saliva (100% vs. 25%, p = 0.04); a mean dose of11 Gy to the minor salivary glands was significantly associated with persistent sticky saliva (100% vs. 25%, p = 0.04), although the difference was no longer significant at 1 year.Limiting the mean parotid dose toor= 31 Gy and mean minor salivary gland dose toor= 11 Gy in lymphoma patients treated to the HN may help reduce the risk of subacute xerostomia.

Purpose There are no data on how complication rates after accelerated partial-breast irradiation delivered by three-dimensional conformal radiotherapy are affected by treatment technique. We therefore examined the risk of pneumonitis in relation to lung dose-volume parameters. Patients and Methods Our prospective dose-escalation trial enrolled 198 treated patients from 2003 to 2007. Patients received 32 or 36 Gy in 4-Gy fractions, given twice daily: 29 (14%) were treated with pure photons; 149 (77%) with mixed photons and electrons; and 20 (10%) with protons. Results There were four cases of pneumonitis at 4, 4, 7, and 9 months after treatment. All were in the 36-Gy cohort and were treated with pure photons. The risk of pneumonitis for the two cohorts combined was: 17% (four of 24) for an ipsilateral lung volume (ILV) receiving 20 Gy or higher (ILV, 20 Gy) of 3% or higher (P = .0002 for comparison to ILV 20 Gy < 3%, Fisher's exact test); 20% (four of 20) for an ILV 10 Gy of 10% or higher (P = .0001); and 15% (four of 26) for an ILV 5 Gy of 20% or higher (P = .0002). Conclusion The risk of pneumonitis appeared related to the ILV treated. This volume can be reduced by using mixed photons and electron when possible. We recommend that the ILV 20 Gy should be lower than 3%, the ILV 10 Gy lower than 10%, and the ILV 5 Gy lower than 20% when purely coplanar techniques are used.

CDC37 is a molecular chaperone that physically stabilizes the catalytic domains found in protein kinases and is therefore a wide-spectrum regulator of protein phosphorylation. It is also an overexpressed oncoprotein that mediates carcinogenesis by stabilizing the compromised structures of mutant and/or overexpressed oncogenic kinases. Recent work shows that such dependency of malignant cells on increased CDC37 expression is a vulnerability that can be targeted in cancer by agents that deplete or inhibit CDC37. CDC37 is thus a candidate for broad-spectrum molecular cancer therapy.

Purpose Respiratory motion presents a significant challenge in stereotactic body radiosurgery. Respiratory tracking that follows the translational movement of the internal fiducials minimizes the uncertainties in dose delivery. However, the effect of deformation, defined as any changes in the body and organs relative to the center of fiducials, remains unanswered. This study investigated this problem and a possible solution. Methods and Materials Dose delivery using a robotic respiratory-tracking system was studied with clinical data. Each treatment plan was designed with the computed tomography scan in the end-expiration phase. The planned beams were applied to the computed tomography scan in end-inspiration following the shift of the fiducials. The dose coverage was compared with the initial plan, and the uncertainty due to the deformation was estimated. A necessary margin from the clinical target volume to the planning target volume was determined to account for this and other sources of uncertainty. Results We studied 12 lung and 5 upper abdomen lesions. Our results demonstrated that for lung patients with properly implanted fiducials a 3-mm margin is required to compensate for the deformation and a 5-mm margin is required to compensate for all uncertainties. Our results for the upper abdomen tumors were still preliminary but indicated a similar result, although a larger margin might be required. Conclusion The effect of body deformation was studied. We found that adequate dose coverage for lung tumors can be ensured with proper fiducial placement and a 5-mm planning target volume margin. This approach is more practical and effective than a recent proposal to combine four-dimensional planning with respiratory tracking.

Heat shock protein 70 (Hsp70) is released from cells of many types and plays a significant signaling role, particularly in the inflammatory and immune responses. However, Hsp70 does not contain a consensus secretory signal and thus cannot traverse the plasma membrane by conventional mechanisms. However, Hsp70 can be released from cells by active mechanism that are independent of de novo Hsp70 synthesis or cell death. This pathway is similar to one utilized by the leaderless protein interleukin 1β. Hsp70 release involves transit through an endolysosomal compartment and is inhibited by lysosomotropic compounds. In addition, the rate of Hsp70 secretion correlates well with the appearance of the lysosomal marker LAMP1 on the cell surface, further suggesting the role for endolysosomes. The entry of Hsp70 into this secretory compartment appears to involve the ABC-family transporter proteins. While the cell signals involved in triggering Hsp70 release through this lysosomal pathway are largely unknown, recent data suggest a regulatory role for extracellular ATP. These mechanisms are also shared by interleukin 1β secretion. Following release it has been shown that Hsp70 binds to adjacent cells, suggesting that the secreted protein participates in paracrine or autocrine interactions with adjacent cell surfaces. Thus an outline is beginning to of the mechanisms of Hsp70 secretion. Much further study will be required to fully elucidate mechanisms involved in targeting Hsp70 towards the non-canonical secretion pathways and its regulation.

Background: Few large studies exist on the outcome of patients treated for stage I/II mucosa-associated lymphoid tissue (MALT) lymphoma. Patients and methods: We retrospectively reviewed the records of 77 patients consecutively treated for stage I (n = 66) or II (n = 11) MALT lymphoma at our institution. Progression-free survival (PFS), freedom from treatment failure (FFTF), and overall survival (OS) were calculated using the Kaplan–Meier method. Results: The median follow-up time was 61 months (range 2–177 months). Fifty-two patients (68%) received local radiation therapy (RT) alone, 17 (22%) had surgery followed by adjuvant RT, five (6%) had surgery alone, two (3%) had surgery and chemotherapy, and one patient had chemotherapy alone. The median RT dose was 30 Gy (range 18–40 Gy). The 5-year PFS, FFTF, and OS rates were 76%, 78%, and 91%, respectively. The 5-year PFS (79% versus 50%; P = 0.002) and FFTF (81% versus 50%; P = 0.0004) rates were higher for patients who received RT as compared with patients who did not. Conclusions: The prognosis following treatment of stage I/II MALT lymphoma is excellent. RT improves PFS and FFTF and has an important role in the curative treatment of patients with localized disease.

Background: To determine the long-term treatment outcome and late effects of mantle irradiation alone in selected patients with early-stage Hodgkin’s disease. Methods: Between 1988 and 2000, 87 patients with pathologic stage (Ann Arbor) I–IIA or clinical stage IA Hodgkin’s disease were entered on to a prospective trial of mantle irradiation alone. Patients with B symptoms, large mediastinal adenopathy, or subcarinal or hilar involvement were excluded. The median doses to the mantle field and mediastinum were 36 Gy (range 30.3–40) and 38.6 Gy (range 30.6–44), respectively. The actuarial freedom from treatment failure (FFTF) and overall survival (OS) rates were calculated using the Kaplan–Meier technique. Results: The median follow-up was 107 months (range 23–192). Thirteen of 87 patients (15%) relapsed at a median of 30 months (range 5–62). The 5- and 10-year actuarial FFTF rates were 86% and 84.7%, respectively. All 13 patients who relapsed are alive without evidence of disease at a median of 84 months (range 30–156) post-salvage therapy. Five patients developed a second malignancy at a median of 93 months (range 27–131). The 10-year actuarial risk of a second malignancy was 4.5%. There have been two deaths to date, both due to second malignancies. The 10-year OS rate was 98.2%. Conclusion: In selected patients with early-stage Hodgkin’s disease, mantle irradiation alone has an excellent long-term survival rate, comparing favorably with the previous standard treatment of extended-field radiation therapy and the current standard of combined modality therapy.

To determine the efficacy of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) for patients with Hodgkin's disease and to identify predictors of outcome with this regimen.Between 1987 and 1998, 175 patients with Stage I-IV Hodgkin's disease received ABVD as part of initial treatment. Overall survival (OS), freedom-from-treatment-failure (FFTF), and progression-free survival (PFS) were calculated using the Kaplan-Meier technique. Log-rank tests were used to identify univariate predictors of OS, FFTF, and PFS. Specifically, restaging gallium scan results and clinical response after chemotherapy were separately evaluated.The median follow-up time was 64 months. The 5-year OS, FFTF, and PFS rates were 90%, 85%, and 82%, respectively. For Stage I-II patients, restaging gallium scan results and clinical response after chemotherapy were highly predictive of OS, FFTF, and PFS (p0.0001). Other significant predictors for higher OS included age50 (p = 0.002), female gender (p = 0.047), and absence of B symptoms (p = 0.043). Of the 20 patients with a positive restaging gallium scan, 4 received high-dose therapy and 16 continued with conventional-dose therapy or received no further treatment. Of these 16 patients, 11 (69%) were disease-free at last follow-up.Although a positive mid- or postchemotherapy gallium scan was an adverse prognostic factor for OS, FFTF, and PFS, continued treatment with conventional-dose therapy may be adequate in selected patients with positive scans.

Background: The aim of this study was to determine salvage outcome in patients with Hodgkin’s disease who relapse after radiation therapy, and to compare the efficacy of mechlorethamine, Oncovin, procarbazine and prednisone (MOPP) versus Adriamycin, bleomycin, vinblastine and dacarbazine (ABVD) as salvage treatment. Patients and methods: One hundred patients with Hodgkin’s disease (97 with stage I–II disease at presentation) who relapsed after radiation therapy alone were salvaged with either MOPP or ABVD. Freedom from second relapse (FFSR) and overall survival (OS) were determined, and prognostic factors for salvage outcome were evaluated. Results: The median follow-up time since salvage therapy was 12 years. The 10-year FFSR and OS rates were 70% and 89%, respectively. Forty-one patients were salvaged with MOPP and 59 received ABVD. The type of salvage chemotherapy did not significantly influence FFSR or OS. Age >50 years at initial diagnosis was the only significant predictor for an inferior FFSR and OS on both univariate and multivariate analyses. Conclusions: The two salvage regimens of MOPP and ABVD had similar efficacy in this group of patients with predominantly early-stage disease at initial radiation therapy. The inferior salvage outcome in patients aged >50 years is a contributing factor to the overall poor prognosis of patients presenting with Hodgkin’s dis

Purpose Many authors have studied the problems associated with the three-field breast treatment, yet the proposed solutions present their own difficulties. This study presents a technique that overcomes these difficulties, reduces scatter to the contralateral breast, and improves setup reproducibility. Methods and materials Patients are set up with both arms raised superiorly on a breast board. A precise field-match is achieved by rotating the couch and collimator of the tangents, while the supraclavicular field is half-beam blocked using an independent jaw. The posterior borders of the tangents are conformally defined by multileaf collimation. Measurements were performed to verify the field matching and evaluate scatter doses. Results A smooth dose transition was found at the match line at all depths. Corner blocks and lower wedges were not used, which reduced the scatter to the contralateral breast compared with our prior technique. Conclusion The technique achieves a precise match while removing constraints on the tangents’ length and decreasing scatter dose. Procedures for simulation, planning, and treatment have been devised, along with a new patient setup routine incorporating orthogonal setup films and tattoos. This technique has been successfully implemented in routine treatment since September 2001. A program calculating the setup parameters is available at our website.

Recent studies have initiated a paradigm shift in the understanding of the function of heat shock proteins (HSP). It is now clear that HSP can and do exit mammalian cells, interact with cells of the immune system, and exert immunoregulatory effects. We recently demonstrated that exogenously added HSP70 possesses potent cytokine activity, with the ability to bind with high affinity to the plasma membrane, elicit a rapid intracellular Ca2+ flux, activate NF-κB, and up-regulate the expression of pro-inflammatory cytokines in human monocytes. Here for the first time, we report that HSP70-induced proinflammatory cytokine production is mediated via the MyD88/IRAK/NF-κB signal transduction pathway and that HSP70 utilizes both TLR2 (receptor for Gram-positive bacteria) and TLR4 (receptor for Gram-negative bacteria) to transduce its proinflammatory signal in a CD14-dependent fashion. These studies now pave the way for the development of highly effective pharmacological or molecular tools that will either up-regulate or suppress HSP70-induced functions in conditions where HSP70 effects are desirable (cancer) or disorders where HSP70 effects are undesirable (arthritis and arteriosclerosis).

Heat shock factor (HSF) 1 is the major heat shock transcription factor that regulates stress-inducible synthesis of heat shock proteins and is also essential in protection against endotoxic shock. Following our previous study, which demonstrated the transcriptional repression of the IL-1beta gene by HSF1 (Cahill, C. M., Waterman, W. R., Xie, Y., Auron, P. E., and Calderwood, S. K. (1996) J. Biol. Chem. 271, 24874-24879), we have examined the mechanisms of transcriptional repression. Our studies show that HSF1 represses the lipopolyliposaccharide-induced transcription of the IL-1beta promoter through direct interaction with the nuclear factor of interleukin 6 (NF-IL6, also known as CCAAT enhancer binding protein (C/EBPbeta), an essential regulator in IL-1beta transcription. We show for the first time that HSF1 binds directly to NF-IL6 in vivo and antagonizes its activity. The HSF1/NF-IL6 interaction involves a sequence of HSF1 containing the trimerization and regulatory domains and the bZip region of NF-IL6. HSF1 has little effect on IL-1beta promoter activity stimulated by the essential monocytic transcription factor Spi.1 but is strongly inhibitory to transcriptional activation by NF-IL6 and to the synergistic activation by NF-IL6 and Spi.1. Because of its ability to bind to specific C/EBP elements in the promoters of multiple genes and its ability to interact with other transcription factors, NF-IL6 is involved in transcriptional regulation of a wide range of genes. Interaction between HSF1 and NF-IL6 could thus be an important mechanism in HSF1 regulation of general gene transcription during endotoxin stress.

We have examined the functional antagonism between the regulator of the heat shock response, HSF1, and NF-IL6, which plays a major role in control of the acute phase response (APR). Agents that activate HSF1 such as heat shock and sodium salicylate inhibit NF-IL6 induced transcription while NF-IL6 activators such as lipopolysaccharide (LPS) and interleukin 6 (IL-6) repressed the stress responsive HSP70B promoter. In transfection studies, the inhibitory effects of HSF1 and NF-IL6 on the c-fms promoter were shown to be highly dose-dependent. Furthermore, heat shock is inhibitory to differentiation-linked expression of macrophage colony stimulating factor (M-CSF) receptor, product of the c-fms gene, which is transcriptionally activated by NF-IL6 but repressed by HSF1. Our studies suggest a strong mutual antagonism between the heat shock response and APR, which may influence the sensitivity and duration of inflammatory responses.

Sarcomas are considered radioresitant and surgery has remained the primary treatment. Adjuvant radiation in the pre and post-operative setting has been shown to improve local control. When adjacent normal tissues limit radiation dose, particularly in the recurrent and metastatic setting, conformal radiation techniques like Stereotactic Body Radiotherapy (SBRT), could be a useful treatment modality. This Chapter discusses the role of SBRT in the treatment of soft tissue sarcomas.

It has previously been demonstrated that hyperthermia can activate prostaglandin synthesis and that prostaglandins are protective against hyperthermia. This study examined the use of inhibitors of prostaglandin synthesis on the response of prostate tumours to hyperthermia. The non-steroidal anti-inflammatory drugs (NSAID) ibuprofen and sulindac, known cyclooxygenase inhibitors that inhibit prostaglandin production, were effective hyperthermia sensitizers and augmented growth delay of DU-145 and PC-3 prostate tumours to combined radiation and hyperthermia treatment protocols. Pre-treatment of mice with ibuprofen and sulindac at hyperthermia sensitizing doses resulted in significant ( p < 0.01) inhibition of hyperthemia-induced serum prostaglandin E 2 . These findings indicate that NSAID may have both sensitizing effects on prostate tumour growth and may function by inhibiting prostaglandin synthesis.

Sodium salicylate (NaSal) and other nonsteroidal anti-inflammatory drugs (NSAIDs) coordinately inhibit the activity of NF-κB, activate heat shock transcription factor 1 and suppress cytokine gene expression in activated monocytes and macrophages. Because our preliminary studies indicated that these effects could be mimicked by inhibitors of signal transduction, we have studied the effects of NSAIDs on signaling molecules potentially downstream of LPS receptors in activated macrophages. Our findings indicate that ribosomal S6 kinase 2 (RSK2), a 90-kDa ribosomal S6 kinase with a critical role as an effector of the RAS-mitogen-activated protein kinase pathway and a regulator of immediate early gene transcription is a target for inhibition by the NSAIDs. NSAIDs inhibited the activity of purified RSK2 kinase in vitro and of RSK2 in mammalian cells and suppressed the phosphorylation of RSK2 substrates cAMP response element binding protein (CREB) and I-κBα in vivo. Additionally, NaSal inhibited the phosphorylation by RSK2 of CREB and I-κBα on residues crucial for their transcriptional activity in vivo and thus repressed CREB and NF-κB-dependent transcription. These experiments suggest that RSK2 is a target for NSAIDs in the inhibition of monocyte-specific gene expression and indicate the importance of RSK2 and related kinases in cell regulation, indicating a new area for anti-inflammatory drug discovery.

Recent studies have shown that the non-steroidal anti-inflammatory drugs (NSAIDs) activate heat shock transcription factor (HSF1) from a latent cytoplasmic form to a nuclear, DNA binding state. As HSF1 can function as both an activator of heat shock genes and a repressor of non-heat shock genes such as IL1B and c- fos, we have examined the potential role of HSF1 in the effects of NSAIDs on gene expression in a human monocytic cell line THP-1. We found that two members of the NSAIDs, sodium salicylate and sulindac repress the IL1B promoter to similar degree to heat shock or HSF1 overexpression. In addition, sodium salicylate and additional NSAIDs used at concentrations that activate HSF1 also inhibited the expression of other monocytic genes (TNF-alpha, IL-1beta, IL-6, IL-8, IL-10, ICAM-1) activated by exposure to a pro-inflammatory stimulus (lipopolysaccharide, LPS). At least in the case of the IL1B promoter, repression did not seem to involve another factor whose activity is affected by the NSAIDs, NFkappaB as the IL1B promoter fragment used in our studies is not NFkappaB responsive and binds specifically to HSF1. Exposure to NSAIDs had a complex effect on HSP gene expression and while sulindac activated the stress responsive HSP70B promoter, sodium salicylate did not. In addition, only a subset of the NSAIDs induced HSP70 mRNA species. These findings reflect the properties of HSF1 which can be activated to at least two DNA binding forms only one of which activates heat shock promoters and suggest that individual NSAID family members may differentially induce one or other of these forms. Overall therefore, exposure to NSAIDs leads to a profound switch in gene expression in monocytic cells, with suppression of genes involved in macrophage activation and induction of stress genes and HSF1 appears to play a regulatory role in these effects.

Cells of the LA7 rat mammary tumor line stimulate proliferation of normal mouse mammary epithelial cells in culture when in direct physical contact with them. We examined junctional connections between these LA7 feeders and the recipient mouse mammary epithelial cells in order to study the role these junctions may play in growth signaling. Tight junctions and desmosomes between LA7 feeders and mouse mammary cells were detected by immunocytochemistry. These junctions connected every cell of either type with each of its neighbors. Adherens junctions, although evident between mouse mammary cells, could not be detected between LA7 and mouse mammary cells or between LA7 cells themselves. However, E-cadherin, the transmembrane protein of adherens junctions, was present in LA7 cell lysates. beta-catenin, which normally binds cadherins, was detected at the borders of LA7 cells. Presence of gap junctions between LA7 and mouse mammary cells was determined by traverse of lucifer yellow from an injected LA7 cell to surrounding mouse mammary epithelial cells. The experiments thus indicate that three types of intercellular junctions occur between cells active in direct cell-cell-stimulated proliferation signaling.

Heat shock factor 1, the critical molecular regulator of the stress response is conserved throughout eukaryotic organisms and activates the transcription of heat shock genes. We now show that heat shock factor 1 inhibits the expression of c-fos, an immediate early gene that controls responses to extracellular stimuli for growth and differentiation. Heat shock factor 1 inhibits the transcription of the c-fos gene and antagonizes the activating effects of the signal transducing protein Ras on the c-fos promoter and on the promoter of another Ras responsive gene uPA. This property was specific for heat shock factor 1; c-fos repression was not seen with the structurally related protein heat shock factor 2. Repression involved different molecular mechanisms compared with those involved in transcriptional activation by heat shock factor 1 and specifically did not require binding to the c-fos promoter. Thus, in addition to its known role as a transcriptional activator of the cellular heat shock response, heat shock factor 1 also antagonizes the expression of Fos, a key component of the ubiquitous AP-1 transcription factor complex and as such could influence multiple aspects of cell regulation.

Mammalian heat shock genes are regulated at the transcriptional level by heat shock factor-1 (HSF-1), a sequence-specific transcription factor. We have examined the role of serine phosphorylation of HSF-1 in the regulation of heat shock gene transcription. Our experiments show that mitogen-activated protein kinases (MAPKs) of the ERK-1 family phosphorylate HSF-1 on serine residues and repress the transcriptional activation of the heat shock protein 70B (HSP70B) promoter by HSF-1 in vivo. These effects of MAPK are transmitted through a specific serine residue (Ser-303) located in a proline-rich sequence within the transcriptional regulatory domain of human HSF-1. However, despite the importance of Ser-303 in transmitting the signal from the MAPK cascade to HSP70 transcription, there was no evidence that Ser-303 could be phosphorylated by MAPK in vitro, although an adjacent residue (Ser-307) was avidly phosphorylated by MAPK. Further studies revealed that Ser-303 is phosphorylated by glycogen synthase kinase 3 (GSK3) through a mechanism dependent on primary phosphorylation of Ser-307 by MAPK. Secondary phosphorylation of Ser-303 by GSK3 may thus repress the activity of HSF-1, and its requirement for priming by MAPK phosphorylation of Ser-307 provides a potential link between the MAPK cascade and HSF-1. Our experiments thus indicate that MAPK is a potent inhibitor of HSF-1 function and may be involved in repressing the heat shock response during normal growth and development and deactivating the heat shock response during recovery from stress.

Heat shock proteins (HSPs) have been linked to the therapy of both cancer and inflammatory diseases, approaches that utilize contrasting immune properties of these proteins. It would appear that HSP family members Hsp60 and Hsp70, whether from external sources or induced locally during inflammation, can be processed by antigen-presenting cells and that HSP-derived epitopes then activate regulatory T cells and suppress inflammatory diseases. These effects also extend to the HSP-rich environments of cancer cells where elevated HSP concentrations may participate in the immunosuppressive tumor milieu. However, HSPs can also be important mediators of tumor immunity. Due to their molecular chaperone properties, some HSPs can bind tumor-specific peptides and deliver them deep into the antigen-processing pathways of antigen-presenting cells (APCs). In this context, HSP-based vaccines can activate tumor-specific immunity, trigger the proliferation and CTL capabilities of cancer-specific CD8+ T cells, and inhibit tumor growth. Further advances in HSP-based anticancer immunotherapy appear to involve improving the properties of the molecular chaperone vaccines by enhancing their antigen-binding properties and combating the immunosuppressive tumor milieu to permit programming of active CTL capable of penetrating the tumor milieu and specifically targeting tumor cells.

Background Hodgkin lymphoma (HL) survivors have an increased risk of secondary malignancies. We analyzed outcomes in patients with lung cancers following HL treatment. Patients and methods Cases of thoracic malignancies were retrospectively identified from a multi-institutional database of 1976 patients treated for HL from 1969 to 2007. Data regarding risk factors, disease characteristics and outcomes were obtained from medical records. Results Lung malignancies were identified in 55 patients a median of 19.5 years after initial HL therapy. Thirty-one patients (56%) had a >10 pack-year history of tobacco use, 48 (87%) received thoracic irradiation and 26 (47%) received alkylating chemotherapy. Of the 42 patients with known stage at lung cancer diagnosis, 23 (55%) were stage IV and 5 (12%) were stage III. The method of lung cancer detection was known for 35 patients; of these, 12 (34%) were detected incidentally. Median survival time after diagnosis was 10 months for all 55 patients. Median survival time for patients with incidentally detected tumors has not been reached with a median follow-up of 39 months. Conclusions Lung malignancies diagnosed in patients successfully treated for HL generally have a dismal prognosis. However, a subset of patients diagnosed incidentally may have potentially curable disease.

Heat shock proteins (HSP) are rapidly induced after stresses such as heat shock and accumulate at high concentrations in cells. HSP induction involves primarily a family of heat shock transcription factors (HSF) that bind the heat shock elements of the HSP genes and mediate transcription in trans. We discuss methods for the study of HSP binding to HSP promoters and the consequent increases in HSP gene expression in vitro and in vivo.

The heat shock response in mammals consists of a complex array of intracellular reactions initiated by stress, although its regulation is poorly understood. We have investigated the role of transmembrane signal transduction in the response, examining mechanisms involved in the activation of phospholipase C (PLC) by heat shock. In rodent fibroblasts permeabilized with digitonin, heat shock and receptor-mediated PLC activity exhibited a strict GTP analog dependency. This indicates that heat shock-mediated phopholipase activation, in common with receptor mediated stimulation, does not involve direct effects on the phospholipases and suggests the participation of GTP binding (G) proteins in the activation process. When cells were treated with the inhibitor pertussis toxin (PTX), the phospholipases retained their inducibility by heat shock, but became refractory to thrombin treatment, indicating that heat shock may influence PLC activity through a distinct population of G proteins compared to thrombin. The data seem to exclude a role for PTX sensitive G proteins in the production of IP3 after heating and suggest a pathway involving the direct thermal activation of the Gq class of G proteins, which are coupled to the PLCβ1 isoform. © 1993 Wiley-Liss, Inc.

Although the mammalian heat shock response has been well characterized, the processes that mediate the induction of the response and the regulation of heat shock protein function are not completely understood. We have investigated the potential role in heat-shocked cells of phosphoinositide-specific phospholipase C (PLC), a membrane enzyme activity involved in transmembrane signal transduction. Our studies indicate that heat shock activates PLC in each of seven cell lines, including cells of human, rat, mouse, and hamster origin. Heat shock produced increases in inositol phosphate concentrations comparable in magnitude to those achieved after simulation with growth factors, indicating that heat shock might initiate transmembrane signaling cascades of potential importance in cellular regulation. Common cellular responses to heat and growth factors also included feedback modulation of PLC by its products and the parallel stimulation of phospholipase A2 activity. In addition to heat shocki, other agents that induce the stress response stimulated PLC activity. The data indicate a close correlation between expression of the mammalian heat shock response and stimulation of PLC activity and indicate a possible role for this enzyme activity in the regulation of some aspects of the stress response. © 1993 Wiley-Liss, Inc.

Purpose The optimal treatment for early-stage, lymphocyte-predominant Hodgkin's lymphoma (LPHL) is not well defined. Treatment has become less aggressive over time in an attempt to reduce iatrogenic complications, such as cardiac mortality and second cancers, but long-term efficacy is unclear. We present the long-term outcome of patients treated at a single institution. Patients and Methods The study population includes 113 patients with stage I or II LPHL treated between 1970 and 2005. Pathologic diagnosis for all patients was confirmed using standard criteria. Ninety-three patients received radiation therapy (RT) alone, 13 received RT with chemotherapy, and seven received chemotherapy alone. Among patients treated with RT, 25 received limited-field, 35 received regional-field, and 46 received extended-field RT. Results Median follow-up was 136 months. Ten-year progression-free survival (PFS) rates were 85% (stage I) and 61% (stage II); overall survival (OS) rates were 94% and 97% for stages I and II, respectively. PFS and OS did not differ among patients who received limited-field, regional-field, or extended-field RT. In contrast, six of seven patients who received chemotherapy alone without RT developed early disease progression and required salvage treatment. Multivariable analysis adjusting for extent of RT, clinical stage, sex, and use of chemotherapy confirmed that the extent of RT was not significantly associated with PFS (P = .67) or OS (P = .99). The addition of chemotherapy to RT did not improve PFS or OS compared with RT alone. Conclusion RT alone leads to sustained disease control and high long-term survival rates in patients with early-stage LPHL. This study supports the use of limited-field RT alone to treat this disease.

Members of the 90-kDa heat shock protein (HSP90) family are known to bind and stabilize intermediates in a wide variety of cell signaling pathways and contribute to their dysregulation in cancer. An important intracellular cofactor for HSP90 is Cdc37, a protein with a broad role in fostering the activities of protein kinases. By targeting Cdc37 using RNA interference, we have shown that the loss of Cdc37 function induces irreversible growth arrest in androgen receptor-positive and -negative prostate carcinoma cells. In contrast to HSP90-directed agents, Cdc37 targeting seems to affect cancer cells through a distinct mechanism and does not significantly deplete the intracellular levels of most known HSP90 client proteins. Instead, Cdc37 depletion inhibits cellular kinase activity and flux through growth-promoting signal transduction cascades. We show that the loss of Cdc37 leads to reduced activity of the Erk, Akt, mTOR, and androgen-induced pathways. We have also discovered synergistic interactions between Cdc37 inactivation and the HSP90-inhibitory anticancer drug 17-(allylamino)-17-demethoxygeldanamycin (17AAG). These interactions involve enhanced degradation of proteins essential for growth and inhibition of 17AAG-induced expression of the antiapoptotic HSP70. Thus, Cdc37 is essential for maintaining prostate tumor cell growth and may represent a novel target in the search for multitargeted therapies based on the HSP90 chaperone system. [Cancer Res 2007;67(24):11942–50]

Purpose: The United States healthcare system has witnessed declining reimbursement and increasing documentation requirements for longer than 10 years. These have decreased the time available to academic faculty for teaching and mentorship. The impact of these changes on the career choices of residents is unknown. The purpose of this report was to determine whether changes have occurred during the past decade in the proportion of radiation oncology trainees from a single institution entering and staying in academic medicine. Methods and Materials: We performed a review of the resident employment experience of Harvard Joint Center for Radiation Therapy residents graduating during 13 recent consecutive years (n = 48 residents). The outcomes analyzed were the initial selection of an academic vs. nonacademic career and career changes during the first 3 years after graduation. Results: Of the 48 residents, 65% pursued an academic career immediately after graduation, and 44% remained in academics at the last follow-up, after a median of 6 years. A later graduation year was associated with a decrease in the proportion of graduates immediately entering academic medicine (odds ratio, 0.78; 95% confidence interval, 0.65–0.94). However, the retention rate at 3 years of those who did immediately enter academics increased with a later graduation year (p = 0.03). Conclusion: During a period marked by notable changes in the academic healthcare environment, the proportion of graduating Harvard Joint Center for Radiation Therapy residents pursuing academic careers has been declining; however, despite this decline, the retention rates in academia have increased.

Elevation of heat shock protein (HSP) levels is widespread in cancer and predicts a poor prognosis and resistance to therapy. We show that HSP elevation in tumor cells can be induced by the highly malignant factor heregulin beta1 (HRGbeta1), which induces HSP expression through heat shock transcription factor 1 (HSF1). Inactivation of the hsf1 gene prevents HSP induction by HRGbeta1. HSP expression is induced through a cascade response initiated by HRGbeta1 binding to c-erbB receptors on the cell surface and which leads to the inhibition of intracellular HSF1 antagonist glycogen synthase kinase 3. HSF1 activated by this pathway plays a key role in the protection of cells from apoptosis and the mediation of anchorage independent growth by HRGbeta1, indicating a role for HSF1 in this tumorigenic pathway.

Purpose: To analyze long-term outcomes and causes of death in patients receiving radiation therapy (RT) for localized, low-grade follicular lymphoma. Methods and Materials: Between 1972 and 2000, 106 patients with Stage I–II, Grade 1–2 follicular lymphoma received RT alone or radiation and chemotherapy (RT/CT). Seventy-four percent had Stage I, and 26% had Stage II disease. Seventy-six percent received RT alone, and 24% received combined RT/CT. Second malignancy rates were compared with an age- and sex-matched population. Results: Median follow-up was 12 years. Median survival time was 19 years. The 5-, 10-, and 15-year overall survival (OS) rates were 93%, 75%, and 62%, respectively. Age ≥60 was the only significant adverse prognostic factor with respect to OS. There were 35 deaths, 20 of which were attributable to lymphoma. Freedom from treatment failure (FFTF) rates at 5, 10, and 15 years were 72%, 46%, and 39%, respectively. Forty-seven patients (48%) relapsed. Tumor size >3 cm was the only significant adverse factor for FFTF. Observed incidence of second malignancy did not significantly exceed expected incidence. Conclusions: Although patients with early-stage, low-grade follicular lymphoma have long median survival, the leading cause of death remains lymphoma. However, patients receiving RT do not have significantly elevated cumulative incidence of second malignancy.

Background Hodgkin's disease survivors have a high risk of subsequently developing thoracic cancers. Our goal was to evaluate the prognosis and treatment outcomes of thoracic cancers after Hodgkin's disease. Patients and methods Thirty-three patients treated for Hodgkin's disease at Harvard-affiliated hospitals subsequently developed small-cell lung carcinoma, non-small-cell lung carcinoma (NSCLC) or mesothelioma. Information was obtained from medical records about the initial treatment for Hodgkin's disease, any salvage therapy, smoking history, and the stage, histology, treatment and survival for thoracic cancers. Results Of the 33 patients, 29 (88%) had a history of radiotherapy to the thorax, 17 (52%) had received alkylating chemotherapy, and 24 (73%) had a known history of smoking. The median time between diagnosis of Hodgkin's disease and diagnosis of thoracic cancer was 17.3 years (range 1.2–27.9 years). Among patients with NSCLC and a known stage, 85% presented with stage III or stage IV disease. Among patients whose treatment details were available, 40% underwent surgery, 40% received radiotherapy and 65% received chemotherapy. The median survival was 9 months (range 1–47 months). Conclusions Most patients with thoracic cancers after Hodgkin's disease have a history of exposure to risk factors and present at an advanced stage. Patients with thoracic cancers after Hodgkin's disease have a poor survival.

The 70 kD heat shock protein (HSP70) plays essential cellular roles in mediating intracellular protein folding and protecting cells from proteotoxic stress. This study has examined the role of HSP70 in the expression of apoptosis in prostate carcinoma cells. Apoptosis was negatively correlated with HSP70 expression in PC-3 cells heat shocked in vivo. Further experiments carried out on an in vitro reconstituted system with isolated nuclei and cytoplasm from PC-3 cells showed that purified HSP70 directly inhibits apoptosis in a dose-dependant manner. Therefore, the potential role of depletion of intracellular HSP70 was examined as a means of inducing apoptosis in PC-3 cancer cells. Depletion of HSP70 by two independent strategies, either with anti-sense oligonucleotides directed against HSP70 mRNA or with the bioflavinoid drug quercetin, led to apoptosis in the absence of stress. In addition, quercetin pre-treatment synergistically enhanced apoptosis in combination with heat shock. Thus, HSP70 plays a physiological role in tumour cells as an inhibitor of apoptosis occurring both spontaneously and after stress and is a potential target for apoptosis-based cancer therapy.