Signal transduction of vitamin K3 for pancreas cancer therapy

We characterized molecular mechanisms of vitamin K3 (VK3)-induced inhibition of proliferation to evaluate VK3 effectiveness in treating advanced pancreatic cancer. A novel endoscopic drug delivery system, ultrasound injection technique, was used to study local effects of VK3. VK3 inhibited pancreas cancer cell growth by rapid phosphorylation of growth factor receptor and cellular signal factors such as extracellular signal-regulated kinase. VK3 also activated apoptosis, and apoptosis inhibitor antagonized the apoptosis pathway without inhibiting cell growth. Thiol antioxidant treatment completely abrogated VK3-induced ERK but not JNK phosphorylation or inhibition of proliferation. Non-thiol antioxidant did not affect ERK phosphorylation or growth inhibitory actions. Arylation was considered the main mechanism of VK3-induced growth inhibition through ERK activation. VK3 may lead to favorable outcomes in the treatment of pancreatic tumors. Detection of ERK phosphorylation in tissue is important to predict VK3 effect. Endoscopic ultrasound-guided fine-needle injection may be beneficial for treating pancreatic cancer with VK3.

[The 9th international conference of the asian clinical oncology society in Japan after a twenty year interval--what is the standpoint of Japan in Asia ?]

The 9th International Conference of the Asia Clinical Oncology Society(ACOS)was held at Gifu Grand Hotel, Gifu Japan on August 25, 26, and 27 2010. The Society was established in Osaka, Japan, in October 1991. Meeting have been held every two years, starting in Osaka, and then to Bangkok, Kunming, Bali, Taipei, Seoul, Beijing, Manila, and now to Gifu. There was a twenty year interval in Japan between meetings in Osaka and Gifu. The main theme of the 9th ACOS was titled "Talk to the Worldwide from Asia," and the sub-theme was titled "Multidisciplinary Treatment for Asian Cancer Patients "For this 9th ACOS, we gathered 42 councilors from Asian countries to serve on the ACOS committee and 365 doctors from Japan to serve on a local organizing committee. For congress program, we scheduled 161 special sessions for the president's lectures, key note lectures, special lectures, educational lectures, symposium, workshop, luncheon seminars, etc. We received about 500 abstracts for oral or poster presentations; among them, 140 abstracts came from Asian countries. As for speakers, 475 were from Japan, 85 from Korea, 34 from Taiwan, 27 from China, over 10 from India, Indonesia, Viet Nam, USA, and other countries. Finally a total of 704 speakers were gathered from 20 countries(from the outside Asia; UK, France, Germany, and Australia). The total number of registered investigators was 1, 136, and the total number of participants, including our congress staffs, volunteers, neighborhood doctors, Gifu citizens, patients, etc., was over 1, 500. In this 9th ACOS we discussed some new ideas, such as Asian cancer statistics, mission, vision and core values of ACOS, new anti-cancer drugs developed from Japan(TS-1 and Xeloda), Inter group clinical trials among Asian countries, less invasive surgery using endoscopic assisted operation, Asian traditional medicine, open workshops with citizens, etc. Moreover, we published a commemorative book entitled" Recent Advances of Cancer in Asian Countries.

Novel strategy with gemcitabine for advanced pancreatic cancer

5-fluorouracil (5-FU) is widely used in chemotherapy for gastric and colorectal cancer, but gemcitabine (GEM), and not 5-FU, is approved as a standard drug for use in pancreatic cancer. Interindividual variation in the enzyme activity of the GEM metabolic pathway can affect the extent of GEM metabolism and the efficacy of GEM chemotherapy. Human equilibrative nucleoside transporter 1 (hENT1) is recognized as a major transporter of GEM into cells. In addition, a factor that activates hENT1 is the inhibition of thymidylate synthase (TS), one of the 5-FU metabolic enzymes; TS inhibition mediates depleting intracellular nucleotide pools, resulting in the activation of the salvage pathway mediated through hENT1. In this paper, the role of 5-FU in GEM-based chemotherapy for pancreatic cancer is discussed with special emphasis on enzymes involved in the 5-FU and GEM metabolic pathways and in the correlation between GEM responsiveness and the expression of 5-FU and GEM metabolic enzymes.

Aberrant methylation of heparan sulfate glucosamine 3-O-sulfotransferase 2 genes as a biomarker in colorectal cancer

AIM

The first aim was to determine whether hypermethylation of certain tumor related genes, including 3OST2, CHFR, RUNX3, and p16, could be detected in Japanese colorectal cancer (CRC) patients. The second was to utilize the most frequently hypermethylated genes as biomarkers for early detection of CRC.

MATERIALS AND METHODS

We investigated the aberrant promoter methylation profile of 4 genes in 129 colorectal tumors and corresponding normal mucosa. For the second step, bowel lavage and blood of the main tumor drainage vein from 21 CRC patients were analyzed.

RESULTS

The 3OST2 gene was the most frequently methylated (57%) and was methylated frequently (9/21, 43%) in bowel lavage but rarely (1/21; 4.7%) in the venous drainage. The concordance between 3OST2 methylation in bowel lavage and corresponding tumor samples was 71.4%.

CONCLUSION

These results may show the possibility of early detection for CRC by examining 3OST2 gene methylation status in DNA extracted from stool.

Clinical significance of aggressive hepatectomy for colorectal liver metastasis, evaluated from the HGF/c-Met pathway

Liver metastasis is one of the most critical factors in deciding the prognosis of patients with colorectal cancer (CRC). Hepatectomy is the most curative treatment for liver metastasis of CRC. The high amount of hepatocyte growth factor (HGF) is produced to promote liver regeneration by hepatectomy. Theoretically, HGF produced after hepatectomy stimulates the progression of CRC cells with c-Met in residual liver. This study was aimed to evaluate the value of hepatectomy towards liver metastasis of CRC in relation to the HGF/c-Met pathway. Ninety-four patients with CRC (including 24 liver metastasis cases) were operated at Gifu University Hospital (2002-2004). For these cases, the expression of c-Met in the primary and liver metastatic sites was evaluated by immunohistochemistry and Western blot. Experiments were also conducted on CT26 murine CRC cell line and a mouse liver metastasis model. In clinical study, the c-Met expression in liver metastatic sites was lower than in the primary sites in 87% of 24 cases. In basic study, the expression of c-Met protein in the liver tumor was significantly lower than in culture cells according to Western blot (p=0.033). The growth of residual liver tumors was not significantly different between 30% hepatectomy group and no operation group. The over-expression of c-Met was closely associated with CRC liver metastases. On the other hand, in liver metastatic lesions, the c-Met expression was reduced in comparison to primary lesions. Therefore, even if serum HGF levels increased due to liver resection during the regeneration period, residual liver metastases of CRC was not promoted in its progression. Aggressive hepatectomy would still be acceptable and favorable as a curative therapy.

Immunohistochemical study of claudin 18 involvement in intestinal differentiation during the progression of intraductal papillary mucinous neoplasm

BACKGROUND AND AIM

A comparison was made between pancreatic ductal adenocarcinoma (PDAC), pancreatic intraepithelial neoplasia (PanIN) and intraductal papillary mucinous carcinoma (IPMC) in order to understand the association between several markers and malignant potential.

PATIENTS AND METHODS

Fifteen surgically resected PDACs and four IPMCs were subjected to immunohistochemistry with primary antibodies to Ki-67, p53, MUC2, Gli-1, and Claudin-18 (CLDN18).

RESULTS

Ki-67, P53, MUC2, Gli-1 and CLDN18 were positive in 6 (50%), 10 (66.6%), 0 (0%), 4 (26.6%), and 6 (40%) of the 15 PDACs, respectively. Low- to high-grade PanIN complexes were found in 2 out of the 15 PDACs. Gli-1 was continuously expressed in low- and high-grade PanINs. CLDN18 was specifically expressed in high-grade PanINs, whereas the corresponding invasive tubules did not express CLDN18. P53 was positively stained in one of the 4 IPMCs in which minimally invasive tubular type carcinomas were observed. Ki-67 and CLDN18 were positively stained in all 4 IPMCs. CLDN18 was specifically expressed in intestinal-type components of IPMCs.

CONCLUSION

CLDN18 is involved in intestinal-type epithelial differentiation in the progression of IPMCs, contradicting the previous knowledge of its specificity in gastric epithelial differentiation.

Combination therapy of 5-fluorouracil with rapamycin for hormone receptor-negative human breast cancer

AIM

To determine a novel chemotherapeutic concept for hormone receptor-negative and HER2-positive breast cancer, a high progression form of the disease for which treatment has been difficult. A combination therapy of 5-fluorouracil (5-FU) with rapamycin (Rap) was examined.

MATERIALS AND METHODS

The growth inhibitory effect of treatment was evaluated by an MTT assay and cellular signal/apoptotic pathways were investigated by Western blotting and Hoechst 33342 staining.

RESULTS

Rap was shown to induce an inhibitory effect on the phosphorylation of mTOR and p70S6K. The expression of thymidine synthase (TS) was decreased by Rap. The addition of 5-FU to Rap was found to increase cell death. The Hoechst 33342 assay showed that apoptosis was increased by the combination of 5-FU and Rap in comparison to 5FU alone.

CONCLUSION

5-FU is more effective in combination with the TS-reducing action of Rap, even for highly HER2-expressing breast cancer cells.

Application of biological study for met expression to cancer therapy

Metastasization is an undesirable process in cancer development and may represent the most critical factor in deciding patient prognosis. Organ specificity of the metastasis process suggests the importance of the paracrine factors: one of the most potent paracrine regulators of tumor cell migration is hepatocyte growth factor/scatter factor (HGF/SF). Because the liver-specific growth factor is HGF, its receptor c-Met expression might play a critical role in metastasization to the liver. Activation of HGF/c-Met signaling has been shown to promote cancer cell invasiveness and trigger metastasis though direct involvement of the angiogenic pathway. Given the importance of aberrant HGF/c-Met signaling, several different therapeutic strategies aimed at inhibiting the pathway have been developed and are currently being evaluated in clinical trials. Among these agents, NK4 and AM102 were introduced as HGF inhibitors, and PHA-665752 and Su11274 as c-Met inhibitors and are under study in clinical trials. Further, clinical experience-based study to apply the accumulation of biological knowledge concerning HGF/c-Met to the surgical field is presented.

Critical role of c-Met and Ki67 in progress of biliary carcinoma

The purpose of this study was to evaluate the pattern of expression of c-Met and Ki67 in several components of biliary carcinoma. Fourteen surgically resected samples, including five intrahepatic cholangiocarcinomas, five gallbladder carcinomas, and four extrahepatic bile duct carcinomas, were subjected to immunohistochemistry with primary antibodies. In all 13 cases, intraductal neoplastic components showed diffuse staining for c-Met localized in the cell membrane, whereas 10 of the 14 cases lacked expression of c-Met in the corresponding invasive components. In four cases, invasive components composed of undifferentiated carcinoma (n = 2), signet-ring cell carcinoma (n = 1), and squamous cell carcinoma (n = 1) showed nuclear or perinuclear staining for c-Met. Conversely, 11 of the 13 cases did not express Ki67 in intraductal neoplastic components, whereas corresponding invasive components showed diffuse nuclear staining in all 14 cases. A comparison of the patterns of expression between c-Met and Ki67 at the boundary between intraductal and invasive components clearly demonstrated the complementary expression of c-Met and Ki67. Our results suggested that c-Met is involved in early events of carcinogenesis and Ki67 is involved in the formation of invasive carcinoma. However, exceptional cases were also observed, which might be associated with specificity for histologic subtypes and malignant potential.

Critical Role of c-Met and Ki67 in Progress of Biliary Carcinoma

The purpose of this study was to evaluate the pattern of expression of c-Met and Ki67 in several components of biliary carcinoma. Fourteen surgically resected samples, including five intrahepatic cholangiocarcinomas, five gallbladder carcinomas, and four extrahepatic bile duct carcinomas, were subjected to immunohistochemistry with primary antibodies. In all 13 cases, intraductal neoplastic components showed diffuse staining for c-Met localized in the cell membrane, whereas 10 of the 14 cases lacked expression of c-Met in the corresponding invasive components. In four cases, invasive components composed of undifferentiated carcinoma (n = 2), signet-ring cell carcinoma (n = 1), and squamous cell carcinoma (n = 1) showed nuclear or perinuclear staining for c-Met. Conversely, 11 of the 13 cases did not express Ki67 in intraductal neoplastic components, whereas corresponding invasive components showed diffuse nuclear staining in all 14 cases. A comparison of the patterns of expression between c-Met and Ki67 at the boundary between intraductal and invasive components clearly demonstrated the complementary expression of c-Met and Ki67. Our results suggested that c-Met is involved in early events of carcinogenesis and Ki67 is involved in the formation of invasive carcinoma. However, exceptional cases were also observed, which might be associated with specificity for histologic subtypes and malignant potential.

A case of esophageal adenocarcinoma arising from the ectopic gastric mucosa in the thoracic esophagus

A 75-year old man was detected with a pediculate tumor in the upper esophagus. A biopsy determined that it was an adenocarcinoma. A subtotal esophagectomy with dissection of three-fields of lymph nodes was selected. The pathological study revealed it to be an esophageal adenocarcinoma arising from ectopic gastric mucosa of the fundus of the stomach. His post-operative course was uneventful and without sign of recurrence for 3.5 years.

Effect of hepatocyte growth factor on progression of liver metastasis in colorectal cancer

BACKGROUND/AIMS

Colorectal cancer (CRC) is one of the most common cancers worldwide, and a strategy to assess and control liver metastasis will be critical to control patient prognosis. To evaluate therapeutic approaches, the biological responses associated with hepatectomy were studied with a focus on hepatocyte growth factor (HGF).

METHODOLOGY

In 54 patients with metastatic liver tumors due to CRC, c-Met expression was estimated by western blotting from resected tissue specimens. Serum HGF levels were measured by an ELISA method and compared with other liver function serum factors.

RESULTS

The preoperative serum level of HGF was found to be related to ICGR15, ALP, CHE and AST, but after hepatectomy, the change was not correlated with other liver function factors. From an evaluation of pre-operative liver condition using ICGR15, an increasing rate (post/pre) of AST, ALT, ALP and HGF was observed to be higher in cases with positive outcomes. In cases with normal pre-operative levels of serum HGF, the increasing rate (post/pre) of HGF after surgery was higher than in cases with abnormally high pre operative values (3.07 +/- 0.87 and 2.38 +/- 0.74, respectively; p = 0.0102). In cases where tumors recurred within 6 months (early recurrence cases), the c-Met value in tumor tissue was higher than in cases with no recurrence, even in cases where there was no tendency for an increasing rate of HGF. In addition, multiplying data serum HGF increasing rate by c-Met value in tissue was significantly higher in early recurrence cases than in cases with no recurrence, (3.96 +/- 0.62 and 3.00 +/- 1.16 respectively; p = 0.0135). A similar finding was also detected following curative operations involving multiple tumor resection (3.93 +/- 0.64 vs. 2.84 +/- 1.24 for early and no recurrence, respectively; p = 0.0147).

CONCLUSION

The present study demonstrated that cancer with high c-Met expression and under high level of its ligand, HGF, led to recurrence soon after hepatectomy, leading to unfavorable patient prognosis. If pathological or biochemical factors from resected specimens could help identify patients with a high risk of relapse, innovative adjuvant chemotherapy protocols could be initiated.

A novel strategy by cryoablation for advanced hepatoma

Ablative techniques have been developed against advanced liver cancer in cases where surgical resection is impossible. Among the ablation procedures used, thermal ablation therapy is widely applied, and the safety and efficacy of this technique in controlling local progression of cancer have been well characterized. However, the principle of cryosurgery is not only to control local recurrence, but also to stimulate the immune system into initiating an antitumor response. In recent years, we have used a liquid nitrogen-based cryogenic procedure and developed a treatment method for patients with unresectable liver tumors. Following this, repeated treatment was demonstrated to induce anticancer immune reaction-related factors. In the present study, a novel strategy as a cryoablation-induced anti-cancer immune reaction is introduced.