Phytochemicals: cancer chemoprevention and suppression of tumor onset and metastasis

Carcinogenesis is a multi-step process which could be prevented by phytochemicals. Phytochemicals from dietary plants and other plant sources such as herbs are becoming increasingly important sources of anticancer drugs or compounds for cancer chemoprevention or adjuvant chemotherapy. Phytochemicals can prevent cancer initiation, promotion, and progression by exerting anti-inflammatory and anti-oxidative stress effects which are mediated by integrated Nrf2, NF-kappaB, and AP-1 signaling pathways. In addition, phytochemicals from herbal medicinal plants and/or some dietary plants developed in recent years have been shown to induce apoptosis in cancer cells and inhibition of tumor growth in vivo. In advanced tumors, a series of changes involving critical signaling molecules that would drive tumor cells undergoing epithelial-mesenchymal transition and becoming invasive. In this review, we will discuss the potential molecular targets and signaling pathways that mediate tumor onset and metastasis. In addition, we will shed light on some of the phytochemicals that are capable of targeting these signaling pathways which would make them potentially applicable to cancer chemoprevention, treatment and control of cancer progression.

Stereotactic radiotherapy of hepatocellular carcinoma: preliminary results

Stereotactic radiotherapy (SRT) offers a treatment option for hepatocellular carcinoma (HCC) patients that are not eligible for surgery, embolization, chemotherapy, or radiofrequency ablation. We have evaluated the feasibility, tolerance and toxicity of SRT for 25 HCC patients who were not eligible for these other modalities. The patients (6 women and 19 men) were treated with CyberKnife stereotactic radiotherapy using respiratory motion tracking. All patients had liver cirrhosis with an Eastern Cooperative Oncology Group (ECOG) performance score of less than 2 and pre-treatment Child scores ranging from A5 to B9. A total dose of 45 Gy in three fractions of 15 Gy each was prescribed to the 80% isodose line (95% of the PTV received 45 Gy) and delivered to the target volume over 10 to 12 days. Overall the treatment was well tolerated with two Grade 3 acute toxicities and no acute Grade 4 toxicities. Late toxicity was minimal with all observed late toxicities occurring within the first six months of follow-up. Three hepatic recurrences at a distance from the target and one metastasis were observed. The actuarial 1- and 2-year local control rate was 95% (95% CI: 69-95%). At a median overall follow-up of 12,7 months (range, 1-24 months), six of the twenty-five (24%) patients have died. Overall actuarial survival at 1- and 2-years was 79% (95% CI: 52-92%) and 52% (95% CI: 19-78%), respectively. Our results suggest promising therapeutic efficacy and good clinical tolerance to CyberKnife SRT treatment for HCC patients not eligible for other treatment modalities.

Stereotactic body radiotherapy for patients with unresectable primary hepatocellular carcinoma: dose-volumetric parameters predicting the hepatic complication

PURPOSE

To identify the parameters that predict hepatic toxicity and deterioration of hepatic function.

MATERIALS AND METHODS

A total of 47 patients with small unresectable primary hepatocellular carcinoma received hypofractionated stereotactic body radiotherapy (SBRT) using the CyberKnife. Of those, 36 patients received no other local treatments that could influence hepatic toxicity at least for 3 months after the completion of SBRT. The gross tumor volume (GTV) was 18.3 ± 15.9 cm(3) (range, 3.0-81.3 cm(3)), and the total dose administered was 30-39 Gy (median, 36 Gy). To assess the deterioration of hepatic function, we evaluated the presence or absence of the progression of Child-Pugh class (CP class). To identify the parameters of predicting the radiation-induced hepatic toxicity and deterioration of the hepatic function, several clinical and dose-volumetric parameters were evaluated.

RESULTS

Of 36 patients, 12 (33%) developed Grade 2 or higher hepatic toxicity and 4 (11%) developed progression of CP class. The multivariate analysis showed that the only significant parameter associated with the progression of CP class was the total liver volume receiving a dose less than 18 Gy (<18 Gy).

CONCLUSIONS

The progression of CP class after SBRT limits other additional local treatments and also reflects the deterioration of hepatic function. Therefore, it would be important to note that the presence or absence of the progression of CP class is a dose-limiting factor. The total liver volume receiving <18 Gy should be greater than 800 cm(3) to reduce the risk of the deterioration of hepatic function.

Early three-dimensional conformal radiotherapy for patients with unresectable hepatocellular carcinoma after incomplete transcatheter arterial chemoembolization: a prospective evaluation of efficacy and toxicity

PURPOSE

We prospectively evaluated the efficacy and toxicity of early 3-dimensional conformal radiotherapy (3D-CRT) for patients with unresectable hepatocellular carcinoma (HCC) after incomplete transcatheter arterial chemoembolization (TACE).

METHODS

Patients with unresectable HCC who failed 1 or 2 courses of TACE were eligible for this study. Three dimensional-CRT was added for HCC with incomplete uptake of iodized oil. Between January 2006 and February 2007, 40 patients (43 lesions) were enrolled. TACE was performed by using Lipiodol and adriamycin, followed by Gelfoam embolization. Two cycles of TACE were performed in 24 patients (60%), whereas 16 patients (40%) underwent one cycle. The median dose of 54 Gy (3 Gy daily) was delivered with 3D-CRT. Tumor response was evaluated by changes in tumor size on serial computed tomography scans and toxicity was evaluated by the Common Terminology Criteria for Adverse Events v3.0.

RESULTS

An objective response was achieved in 27 of 43 lesions (62.8%), with a complete response in 9 lesions (20.9%) and partial response in 18 lesions (41.9%). The overall survival rate was 72.0% at 1 year and 45.6% at 2 years. There was no grade 3 or greater acute toxicity. Nine patients (22.5%) showed progression of the disease within the irradiated field during the follow-up and intrahepatic metastases developed in 16 patients (40.0%).

CONCLUSION

Early 3D-CRT for HCC unresponsive to 1 or 2 cycles of TACE resulted in a 62.8% tumor response rate and relatively high complete response rates (20.9%) with acceptable toxicity. This study shows that the application of 3D-CRT could be considered for patients with incomplete TACE.

Long-term effect of stereotactic body radiation therapy for primary hepatocellular carcinoma ineligible for local ablation therapy or surgical resection. Stereotactic radiotherapy for liver cancer

BACKGROUND

We evaluated the long-term effect of stereotactic body radiation therapy (SBRT) for primary small hepatocellular carcinoma (HCC) ineligible for local therapy or surgery.

METHODS

Forty-two HCC patients with tumors ≤ 100 cc and ineligible for local ablation therapy or surgical resection were treated with SBRT: 30-39 Gy with a prescription isodose range of 70-85% (median 80%) was delivered daily in three fractions. Median tumor volume was 15.4 cc (3.0-81.8) and median follow-up duration 28.7 months (8.4-49.1).

RESULTS

Complete response (CR) for the in-field lesion was initially achieved in 59.6% and partial response (PR) in 26.2% of patients. Hepatic out-of-field progression occurred in 18 patients (42.9%) and distant metastasis developed in 12 (28.6%) patients. Overall in-field CR and overall CR were achieved in 59.6% and 33.3%, respectively. Overall 1-year and 3-year survival rates were 92.9% and 58.6%, respectively. In-field progression-free survival at 1 and 3 years was 72.0% and 67.5%, respectively. Patients with smaller tumor had better in-field progression-free survival and overall survival rates (<32 cc vs. ≥32 cc, P < 0.05). No major toxicity was encountered but one patient died with extrahepatic metastasis and radiation-induced hepatic failure.

CONCLUSIONS

SBRT is a promising noninvasive-treatment for small HCC that is ineligible for local treatment or surgical resection.

[Nonsurgical management of hepatocellular carcinoma]

Most of patients with hepatocellular carcinoma (HCC) cannot benefit from surgical therapies. Among nonsurgical options, only radiofrequency can challenge surgery for small size tumours. Conformal radiotherapy is likely highly efficient on solitary tumours, but controlled studies are warranted to conclude. Other options are purely palliative. Transarterial hepatic chemoembolization is the goal-standard for multifocal hepatocellular carcinoma and sorafenib for hepatocellular carcinoma with portal vein invasion, leading to modest but significant benefit on survival rates. Yttrium-90 radioembolization is under evaluation through controlled studies, and could be of major interest for multifocal hepatocellular carcinoma with or without portal venous invasion.

Nonsurgical options for hepatocellular carcinoma: evolving role of external beam radiotherapy

BACKGROUND

Hepatocellular carcinoma (HCC) is the sixth most common cancer worldwide and thus poses a global concern. Its incidence is expected to increase in North America secondary to the increasing incidence of patients who develop hepatitis C. Patients who ultimately develop cirrhosis have an increased risk of developing hepatocellular carcinoma.

METHODS

The authors focus on nonsurgical therapies for this disease with an exploration of how external beam radiotherapy can be used alone or with other modalities. The development of partial liver strategies secondary to an explosion in radiation treatment planning and delivery advances is reviewed. Integration of advanced technology has evolved from three-dimensional conformal treatment to intensity-modulated radiation therapy and image-guided radiation therapy, along with stereotactic body radiation therapy, tomotherapy, and proton beam therapy.

RESULTS

Current data show a promising future for treatment strategies incorporating radiation with high rates of infield tumor control and low rates of radiation-induced liver disease. Radiation can be delivered in conjunction with transarterial catheter embolization for advanced-stage patients. External beam radiotherapy also has a role in the setting of patients with macrovascular tumor thrombus.

CONCLUSIONS

Future directions include how to best synergize the effects of radiation strategies with novel agents, given the hypervascularity of HCC. Downstaging of larger lesions with these therapies to resectable or transplantable disease may lead to better outcomes for patients deemed inoperable at diagnosis, and definitive radiotherapy may offer cure to patients with smaller lesions.

Phase I feasibility trial of stereotactic body radiation therapy for primary hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is increasing in incidence and the majority of patients are not candidates for radical therapies. Therefore, interest in minimally invasive therapies in growing.

METHODS

A Phase I dose escalation trial was conducted at Indiana University to determine the feasibility and toxicity of stereotactic body radiation therapy (SBRT) for primary HCC. Eligible patients had Child-Turcotte-Pugh's Class (CTP) A or B, were not candidates for resection, had 1-3 lesions and cumulative tumour diameter less than or equal to 6 cm. Dose escalation started at 36 Gy in 3 fractions (12 Gy/fraction) with a subsequent planned escalation of 2 Gy/ fraction/level. Dose-limiting toxicity (DLT) was defined as Common Terminology Criteria for Adverse Events v3.0 grade 3 or greater toxicity.

RESULTS

Seventeen patients with 25 lesions were enrolled. Dose was escalated to 48 Gy (16 Gy/fraction) in CTP-A patients without DLT. Two patients with CPC-B disease developed grade 3 hepatic toxicity at the 42-Gy (14 Gy/fraction) level. The protocol was amended for subsequent CTP-B patients to receive a regimen of 5 fractions starting at 40 Gy (8 Gy/fraction) with one patient experiencing progressive liver failure. Four additional patients were enrolled (one died of unrelated causes after an incomplete SBRT course) without DLT. The only factor related to more than one grade 3 or greater liver toxicity or death within 6 months was the CTP score (p=0.03). Six patients underwent a liver transplant. Ten patients are alive without progression with a median FU of 24 months (10-42 months), with local control/stabilisation of the disease of 100%. One and two-year Kaplan-Meier estimates for overall survival are 75% and 60%, respectively.

CONCLUSIONS

SBRT is a non-invasive feasible and well tolerated therapy in adequately selected patients with HCC. The preliminary local control and survival are encouraging. A confirmatory Phase II trial is currently open to accrual.

Cyberknife stereotactic body radiation therapy for nonresectable tumors of the liver: preliminary results

Purpose. Stereotactic body radiation therapy (SBRT) has emerged as a treatment option for local tumor control of primary and secondary malignancies of the liver. We report on our updated experience with SBRT in patients with non-resectable tumors of the liver. Methods. Our first 17 consecutive patients (mean age 58.1 years) receiving SBRT for HCC (n = 6), IHC (n = 3), and LM (n = 8) are presented. Mean radiation dose was 34Gy delivered over 1–3 fractions. Results. Treated patients had a mean decrease in maximum pretreatment tumor diameter from 6.9 ± 4.6 cm to 5.0 ± 2.1 cm at three months after treatment (P < .05). The mean total tumor volume reduction was 44% at six months (P < .05). 82% of all patients (14/17) achieved local control with a median follow-up of 8 months. 100% of patients with HCC (n = 6) achieved local control. Patients with surgically placed fiducial markers had no complications related to marker placement. Conclusion. Our preliminary results showed that SBRT is a safe and effective local treatment modality in selected patients with liver malignancies with minimal adverse events. Further studies are needed to define its role in the management of these malignancies.

Dose-volume histogram analysis of the safety of proton beam therapy for unresectable hepatocellular carcinoma

PURPOSE

To evaluate the safety and efficacy of radiotherapy using proton beam (PRT) for unresectable hepatocellular carcinoma.

METHODS AND MATERIALS

Sixty consecutive patients who underwent PRT between May 1999 and July 2007 were analyzed. There were 42 males and 18 females, with a median age of 70 years (48-92 years). All but 1 patient had a single lesion with a median diameter of 45 mm (20-100 mm). Total PRT dose/fractionation was 76-cobalt Gray equivalent (CGE)/20 fractions in 46 patients, 65 CGE/26 fractions in 11 patients, and 60 CGE/10 fractions in 3 patients. The risk of developing proton-induced hepatic insufficiency (PHI) was estimated using dose-volume histograms and an indocyanine-green retention rate at 15 minutes (ICG R15).

RESULTS

None of the 20 patients with ICG R15 of less than 20% developed PHI, whereas 6 of 8 patients with ICG R15 values of 50% or higher developed PHI. Among 32 patients whose ICG R15 ranged from 20% to 49.9%, PHI was observed only in patients who had received 30 CGE (V30) to more than 25% of the noncancerous parts of the liver (n = 5) Local progression-free and overall survival rates at 3 years were 90% (95% confidence interval [CI], 80-99%) and 56% (95% CI, 43-69%), respectively. A gastrointestinal toxicity of Grade ≥2 was observed in 3 patients.

CONCLUSIONS

ICG R15 and V30 are recommended as useful predictors for the risk of developing PHI, which should be incorporated into multidisciplinary treatment plans for patients with this disease.

Characterisation of a novel cell line (CSQT-2) with high metastatic activity derived from portal vein tumour thrombus of hepatocellular carcinoma

BACKGROUND

Portal vein tumour thrombus (PVTT) is highly associated with the progression and metastasis of hepatocellular carcinoma (HCC). However, there are no appropriate cell models of PVTT with which to study the biological and physiological characteristics of PVTT.

METHODS

Primary cell culture was performed by the use of a successive xenograft line called PVTT-#1, which was obtained from a 60-year-old male HCC patient accompanied by PVTT.

RESULTS

A successive cell line named CSQT-2 was established. The cell line showed aggressive phenotypes in terms of cell growth, survival, migration, xenograft and metastasis. Moreover, an orthotopic transplantation assay showed that PVTT can be generated in nude mice when CSQT-2 cells were inoculated in the liver and that it shows a typical migratory tendency in the vascular branches of portal vein. Moreover, the established CSQT-2 cells also showed varied expression of tumour-initiating cell (TIC) markers such as CD133, CD90 and EpCAM.

CONCLUSION

Establishment of CSQT-2 may provide a suitable model with which to investigate the molecular mechanisms of PVTT-related HCC.

Tumor-targeted intracellular delivery of anticancer drugs through the mannose-6-phosphate/insulin-like growth factor II receptor

Tumor-targeting of anticancer drugs is an interesting approach for the treatment of cancer since chemotherapies possess several adverse effects. In the present study, we propose a novel strategy to deliver anticancer drugs to the tumor cells through the mannose-6-phosphate/insulin-like growth factor receptor (M6P/IGF-IIR) which are abundantly expressed in several human tumors. We developed a drug carrier against M6P/IGF-II receptor by modifying human serum albumin (HSA) with M6P moieties. M6P-HSA specifically bound and internalized into M6P/IGF-IIR-expressing B16 melanoma cells as demonstrated with radioactive studies and anti-HSA immunostaining. In vivo, M6P-HSA rapidly accumulated in subcutaneous tumors in tumor and stromal components after an intravenous injection. To demonstrate the application of M6P-HSA as a drug carrier, we coupled doxorubicin to it. Dox-HSA-M6P conjugate could release doxorubicin at lysosomal pH and showed M6P-specific binding and uptake in tumor cells. In vitro, a short exposure with Dox-HSA-M6P induced killing of tumor cells, which could be blocked by excess M6P-HSA. In vivo, Dox-HSA-M6P distributed to tumors and some other organs while free doxorubicin distributed to all organs but slightly to tumors. In B16 tumor-bearing mice, Dox-HSA-M6P significantly inhibited the tumor growth whereas an equimolar dose of free doxorubicin did not show any anti-tumor effect. In addition, targeted doxorubicin did not show any side-effects on liver and kidney function tests, body weight and blood cell counts. In conclusion, M6P-HSA is a suitable carrier for delivery of anticancer drugs to tumors through M6P/IGF-IIR. Improved antitumor effects of the targeted doxorubicin by M6P-HSA suggest that this novel approach may be applied to improve the therapeutic efficacy of anticancer drugs.

Relationship of insulin-like growth factors system gene polymorphisms with the susceptibility and pathological development of hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is one of the major causes of cancer-related death worldwide. The insulin-like growth factors (IGFs) system consists of a group of proteins which may induce cell proliferation and inhibit cell apoptosis through several signal pathways, leading to transformation of normal cells into cancer cells. However, the impact of genetic polymorphisms of the IGFs system on HCC has not been clarified.

METHODS

In this case-control study, a total of 102 HCC patients and 306 age- and gender-matched controls were recruited. The genetic polymorphisms of the IGFs system genes, including IGF-1, IGF-2, IGF-1receptor (IGF-1R), IGF-2R, IGF binding protein (IGFBP-3), and insulin (INS) genes, were analyzed by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) and real-time PCR genotyping analysis.

RESULTS

A significant difference (p = 0.02) between case and control group in the distribution frequency of IGF-2 +3580 polymorphism was observed. Multiple regression model analysis showed that the presence of AA or AG at IGF-2R may exhibit a potential protective effect against hepatitis C [odds ratio (OR) = 0.35, 95% confidence interval (CI) = 0.15-0.82]. The combination of IGF-2 +3580 AA genotype and IGF-2R GG genotype may present a significantly lower risk of HCC (OR = 0.20, 95% CI = 0.05-0.87). Additionally, no polymorphisms of any IGFs system genes were associated with liver-related clinicopathological markers in serum.

CONCLUSIONS

Among IGFs system genes, IGF-2 and IGF-2R gene polymorphisms and combination could be considered as the most important factors contributing to increased susceptibility and pathological development of HCC.

Stereotactic body radiotherapy: a review

Stereotactic body radiotherapy (SBRT) combines the challenge of meeting the stringent dosimetric requirements of stereotactic radiosurgery with that of accounting for the physiological movement of tumour and normal tissue. Here we present an overview of the history and development of SBRT and discuss the radiobiological rationale upon which it is based. The published results of SBRT for lung, liver, pancreas, kidney, prostate and spinal lesions are reviewed and summarised. The current evidence base is appraised and important ongoing trials are identified.

Approach to radiation therapy in hepatocellular carcinoma

Hepatocellular carcinoma (HCC), the 5th most common cancer and the third most common cause of cancer-related death in the world with an estimated incidence of approximately 1 million new cases annually, has becoming a major global health problem in the world. A variety of treatment modalities, including resection, liver transplantation, transarterial chemoembolization (TACE), local ablative therapy and radiation therapy (RT) have been reported. Although partial hepatectomy and liver transplantation may offer the best chance of cure, only 15% of the patients have the chance to be treated by surgery when diagnosed. The effectiveness of systemic chemotherapy for HCC has been minimal, and local ablative therapy may offer comparable survival in patients with small HCC and preserve liver function. Recently, with developments in radiotherapy techniques, radiotherapy has been shown to play potential roles in a wide spectrum of HCC and to become more important so that it is necessary to evaluate the effect of radiotherapy in treatment of HCC. This paper is aiming mainly at the current radiation therapy strategies and their current advances, the optimal radiation therapy strategies will complement the current treatments and improve the treatment efficiency.

Complete necrosis after transarterial chemoembolization could predict prolonged survival in patients with recurrent intrahepatic hepatocellular carcinoma after curative resection

BACKGROUND

We explored the predictors of response to transarterial chemoembolization (TACE) in patients with recurrent intrahepatic hepatocellular carcinoma (HCC) after hepatectomy and investigated the survival of these patients according to the response to TACE.

METHODS

We analyzed data from 199 consecutive HCC patients who underwent curative liver resection and who later received repeat TACE for intrahepatic HCC recurrence.

RESULTS

Of 199 patients, 139 (69.8%) achieved complete necrosis (CN) of HCC after repeated TACE (mean TACE session number, 1.3) and the other 60 (30.2%) (non-CN group) did not achieve CN. At hepatectomy, the CN group showed significantly smaller proportions of tumor capsular invasion, microvascular invasion, and pathologic tumor-node-metastasis stage III or IV HCCs. At first TACE, the CN group showed a significantly greater proportion of patients with time to recurrence > or = 1 year, Child-Pugh class A, serum alpha-fetoprotein (AFP) levels < 200 ng/mL, tumor size < 3 cm, solitary tumors, and nodular tumor types; portal vein invasion were less common than seen in the non-CN group. After multivariate analysis, tumor size < 3 cm and a single tumor at first TACE were independently related to attainment of CN after TACE. Median survival after first TACE was significantly longer in the CN group (48.9 versus 17.0 months). In a Cox regression model, CN after TACE was an independent predictor of favorable survival outcome after first TACE.

CONCLUSIONS

CN after repeat TACE for postresection intrahepatic recurrence was attained more commonly in patients with smaller tumor size and lower tumor number at first TACE and favored longer survival in recurrent patients.

Stereotactic body radiation therapy: a novel treatment modality

Stereotactic body radiation therapy (SBRT) involves the delivery of a small number of ultra-high doses of radiation to a target volume using very advanced technology and has emerged as a novel treatment modality for cancer. The role of SBRT is most important at two cancer stages-in early primary cancer and in oligometastatic disease. This modality has been used in the treatment of early-stage non-small-cell lung cancer, prostate cancer, renal-cell carcinoma, and liver cancer, and in the treatment of oligometastases in the lung, liver, and spine. A large body of evidence on the use of SBRT for the treatment of primary and metastatic tumors in various sites has accumulated over the past 10-15 years, and efficacy and safety have been demonstrated. Several prospective clinical trials of SBRT for various sites have been conducted, and several other trials are currently being planned. The results of these clinical trials will better define the role of SBRT in cancer management. This article will review the radiobiologic, technical, and clinical aspects of SBRT.

Anthocyanins from black soybean seed coats stimulate wound healing in fibroblasts and keratinocytes and prevent inflammation in endothelial cells

Wound healing is a complex process that includes inflammation, tissue formation, and remodeling. While wound healing is accompanied by inflammatory reactions, chronic inflammation impairs acute wound healing. In this study, we investigated whether anthocyanins from black soybean seed coats could stimulate wound healing while preventing excessive inflammation. At 24h of treatment with anthocyanins, fibroblasts showed a significant increase in migration at 100 microg/mL whereas the migration of keratinocytes increased significantly at 50 and 100 microg/mL compared to control. Treatment of anthocyanins for 48 h significantly stimulated the migration of both human dermal fibroblasts and keratinocytes at 50 and 100 microg/mL concentrations. Treatment of cells with anthocyanins stimulated wound-induced VEGF production in fibroblasts and keratinocytes. However, anthocyanins inhibited ROS accumulation and VEGF production in TNF-alpha-stimulated endothelial cells. Furthermore, treatment of anthocyanins reduced, in a dose-dependent manner, the adhesion of inflammatory monocytes to endothelial cells. Anthocyanins also blocked both the translocation of nuclear factor-kappa B (NF-kappaB) p65 into the nucleus and the phosphorylation of the inhibitory factor kappaBalpha (IkappaBalpha). Thus, treatment with anthocyanins from black soybean seed coats may be a potential therapeutic strategy to promote wound healing and to prevent inflammation in a persistent inflammatory condition.

Molecular pathology of early stage chemically induced hepatocarcinogenesis

In the early stage of chemically induced hepatocarcinogenesis, rare hepatocytes are transformed into preneoplastic hepatocytes, which progressively evolve into cells with increasing neoplastic phenotypes. Preneoplastic hepatocytes have gene expression different from normal hepatocytes, presumably from the outset. Some of these gene products are related to the growth and survival of the preneoplastic hepatocytes themselves, while others seem to involve the interaction of preneoplastic hepatocytes with non-parenchymal cell components (paracrine mechanism). Carcinogen treatment, in contrast, usually causes chronic liver injury and continuous liver regeneration, which causes selective expansion of neoplastic hepatocytes due to the fact that the neoplastic hepatocytes are resistant to cellular stress, while proliferation of normal hepatocytes is suppressed by this stress. The formation of neoplastic lesions seems to create a new microenvironment within/around the lesions, which in turn may isolate the preneoplastic hepatocytes from the normal hepatic tissues, further favoring the survival and proliferation of the preneoplastic hepatocytes. Transformation of normal hepatocytes into preneoplastic hepatocytes, their selection for growth and their isolation from the normal hepatic environment are therefore considered the fundamental principles for hepatocarcinogenesis, and this unique gene expression in preneoplastic hepatocytes together with changes in the affected liver are thought to be related to these phenomena.

Screening of herbal medicines for the recovery of cisplatin-induced nephrotoxicity

The goal of this study was to quantitatively determine the recovery effects of herbal medicines (HM) on the cisplatin-induced nephrotoxicity. In the present study, the recovery effects of 239 HM on HEK 293 cells that had been damaged by cisplatin were evaluated by a mitochondrial activity MTS assay. After the first round of screening, candidate HM were selected based on a recovery rate of greater than 20%. The efficacy of the selected herbs was then determined by dose response kinetic analysis. Of the extracts evaluated, 7 HM (Paeonia suffruticosa (PS), Curcuma longa (CL), Centipeda minima (CM), Loranthus parasiticus (LP), Pulsatilla dahurica (PD), Sinapis alba (SA), and Scutellaria barbata (SB)) had a strong recovery effect on cisplatin-induced damage in HEK 293 cells. An LDH assay showed that LP, CM, SB, CL, SA, and PS had the best recovery effect, whereas a comet assay indicated that PS, SB, SA, PD, and CL had the best recovery effect. Taken together, these results suggest that SB, CL, PS, and SA are the best candidate HM for the recovery of cisplatin-induced nephrotoxicity. Therefore, additional studies should be conducted to determine if these HM possess novel therapeutic agents that can be used for the prevention or treatment of renal disorders.

Mannose-6-phosphate/insulin-like growth factor 2 receptor (M6P/IGF2R) in carcinogenesis

The cation-independent mannose-6-phosphate/insulin-like growth factor 2 receptor (M6P/IGF2R) is a multifunctional receptor. It is involved in a variety of cellular processes which become dysregulated in cancer. Its tumor suppressor role was recognized a long time ago. However, due to its multifunctionality, it is not easy to understand the extent of its relevance to normal cellular physiology. Accordingly, it is even more difficult understanding its role in carcinogenesis. This review presents critical and focused highlights of data relating to M6P/IGF2R, obtained during more than 25 years of cancer research.

Current clinical evidence for proton therapy

Proton beam therapy provides the opportunity for more localized delivery of ionizing radiation with the potential for improved normal tissue avoidance to reduce treatment related morbidity and to allow for dose escalation to improve disease control and survival without increased toxicity. However, a systematic review of published peer-reviewed literature reported previously and updated here is devoid of any clinical data demonstrating benefit in terms of survival, tumor control, or toxicity in comparison with best conventional treatment for any of the tumors so far treated including skull base and ocular tumors, prostate cancer and childhood malignancies. The current lack of evidence for benefit of protons should provide a stimulus for continued research. Well designed in silico clinical trials using validated normal tissue complication probability-models are important to predict the magnitude of benefit for individual tumor sites but the future use of protons should be guided by clear evidence of benefit demonstrated in well-designed prospective studies, away from commercial influence, and this is likely to require international collaboration. Any complex and expensive technology, including proton therapy, should not be employed on the basis of belief alone and requires testing to avoid inappropriate use of potential detriment to future patients.

Innovative therapy for hepatocellular carcinoma: three-dimensional high-dose photon radiotherapy

The development of three-dimensional conformal radiotherapy (3DCRT) has enabled high dose radiation to be directed to tumour with a frank sparing of the non-tumour surrounding liver parenchyma without restriction due to tumour topography and size, presence of peritumourous satellite nodules or associated segmental portal vein thrombosis. 3DCRT can be safely delivered alone or concomitantly with transarterial chemoembolization (TACE), giving very encouraging results. Efficacy is strongly related to a smaller tumor size and higher dose of radiation while toxicity closely correlates to the pre-radiotherapy liver functions and the dose delivered to the uninvolved liver. These data has led to integrate 3DCRT in the multimodal treatment of HCC as a possible curative-intent option as well as surgical resection or percutaneous procedures although phase-III controlled studies are warranted to clarify this point. This may represent a promising approach in patients who are inoperable or for whom other ablation therapies are not feasible. The next steps will be the optimization of delivery modes of this type of photon therapy, taking account that other radiation modalities such as proton beam therapy for instance might be shown as of great interest within the next few years.

Interactions of IGF-II with the IGF2R/cation-independent mannose-6-phosphate receptor mechanism and biological outcomes

The cation-independent mannose-6-phosphate/insulin-like growth factor-II receptor (IGF2R) is a membrane-bound glycoprotein consisting of 15 homologous extracellular repeat domains. The major function of this receptor is trafficking of lysosomal enzymes from the trans-Golgi network to the endosomes and their subsequent transfer to lysosomes. The IGF2R also plays a major role in binding and regulating the circulating and tissue levels of IGF-II. As this ligand is important for cell growth, survival, and migration, the maintenance of correct IGF-II levels influences its actions in normal growth and development. Deregulation of IGF2R expression has therefore been associated with growth related disease and cancer. This review highlights recent advances in understanding the IGF2R structure and mechanism of interaction with its ligands, in particular IGF-II. Recent mutagenesis studies combined with the crystal structure of domains 11-14 in complex with IGF-II have mapped the sites of interaction and explain how the IGF2R specificity for IGF-II is achieved. The role of domain 13 in high-affinity IGF-II binding is also revealed. Characterization of ligand:IGF2R interactions is vital for the understanding of the mechanism of IGF2R actions and will allow the development of specific cancer therapies in the future.

Stereotactic body radiation therapy with or without transarterial chemoembolization for patients with primary hepatocellular carcinoma: preliminary analysis

BACKGROUND

The objectives of this retrospective study was to evaluate the efficacy of stereotactic body radiation therapy (SBRT) for small non-resectable hepatocellular carcinoma (HCC) and SBRT combined with transarterial chemoembolization (TACE) for advanced HCC with portal vein tumor thrombosis (PVTT).

METHODS

Thirty one patients with HCC who were treated with SBRT were used for the study. We studied 32 HCC lesions, where 23 lesions (22 patients) were treated targeting small non-resectable primary HCC, and 9 lesions (9 patients) targeting PVTT using the Cyberknife. All the 9 patients targeting PVTT received TACE for the advanced HCC. Tumor volume was 3.6-57.3 cc (median, 25.2 cc) and SBRT dose was 30-39 Gy (median, 36 Gy) in 3 fractions for consecutive days for 70-85% of the planned target volume.

RESULTS

The median follow up was 10.5 months. The overall response rate was 71.9% [small HCC: 82.6% (19/23), advanced HCC with PVTT: 44.4% (4/9)], with the complete and partial response rates of 31.3% [small HCC: 26.1% (6/23), advanced HCC with PVTT: 11.1% (1/9)], and 50.0% [small HCC: 56.5% (13/23), advanced HCC with PVTT: 33.3% (3/9)], respectively. The median survival period of small HCC and advanced HCC with PVTT patients was 12 months and 8 months, respectively. No patient experienced Grade 4 toxicity.

CONCLUSION

SBRT for small HCC and SBRT combined with TACE for advanced HCC with PVTT showed feasible treatment modalities with minimal side effects in selected patients with primary HCC.

Stereotactic body radiation therapy: transcending the conventional to improve outcomes

BACKGROUND

Intracranial delivery of high-dose radiation treatment with stereotactic techniques has paved the way for treatment of extracranial sites.

METHODS

The authors review the evolution of stereotactic body radiation therapy (SBRT) and its application to tumors in the lung and abdomen, addressing both the technical concerns associated with treatment delivery and the emerging clinical data.

RESULTS

Radiation delivery systems have overcome the obstacles with immobilization, respiration, visualization, and daily reproducible imaging. Lung SBRT has been associated with local control rates of over 90%, and liver SBRT has ranged from 55% to 93%. SBRT is being explored in other sites such as the pancreas and kidney. Mature data from ongoing trials will be available in the next 5 years.

CONCLUSIONS

Modern stereotactic radiation treatment techniques allow the safe delivery of high doses to extracranial sites with minimal toxicity, which results in improved outcomes.

A systematic literature review of the clinical and cost-effectiveness of hadron therapy in cancer

BACKGROUND

In view of the continued increase in the number of hadron (i.e. neutron, proton and light or heavy ion) therapy (HT) centres we performed a systematic literature review to identify reports of the efficacy of HT.

METHODS

Eleven databases were searched systematically. No limit was applied to language or study design. Established experts were contacted for unpublished data. Data on outcomes were extracted and summarised in tabular form.

RESULTS

Seven hundred and seventy three papers were identified. For proton and heavy ion therapy, the number of RCTs was too small to draw firm conclusions. Based on prospective and retrospective studies, proton irradiation emerges as the treatment of choice for some ocular and skull base tumours. For prostate cancer, the results were comparable with those from the best photon therapy series. Heavy ion therapy is still in an experimental phase.

CONCLUSION

Existing data do not suggest that the rapid expansion of HT as a major treatment modality would be appropriate. Further research into the clinical and cost-effectiveness of HT is needed. The formation of a European Hadron Therapy Register would offer a straightforward way of accelerating the rate at which we obtain high-quality evidence that could be used in assessing the role of HT in the management of cancer.